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2020-09-01 | We investigated the rheological behavior of linear low-density polyethylene (LLDPE)/polylactic acid (PLA) blends in the presence of modified and non-modified silica nanoparticles in extensional flow. Characterization methods were used as Fourier transform infrared spectroscopy, scanning electron microscopy, and rheometric measurements under shear and uniaxial extensional flows. The rheology behavior of LLDPE significantly was changed by the addition of PLA and silica nanoparticles. Extensional results showed that the elongational viscosity of the blends intensified by the incorporation of silica nanoparticles. Strain hardening was observed for LLDPE containing 2 wt.% of the unmodified silica nanoparticles, which disappeared by enhancement of the unmodified silica from 2 to 8 wt.%. Furthermore, elongation thinning was observed for the filled blends at high loading, which was more sensitive to the strain rate by increasing of PLA. Surface modification of silica was demonstrated in different elongational behavior. Indeed, a fracture took place by loading the modified silica nanoparticles in LLDPE; however, the intensity of this behavior dramatically increased for filled blends with a high loading of modified silica. Graphical abstract | Elongational behavior of silica nanoparticle-filled low-density polyethylene/polylactic acid blends and their morphology | 10.1007/s00397-020-01225-5 |
2020-09-01 | Abstract The use of ultrahigh-molecular-weight polyethylene (UHMWPE) in manufacturing is proposed—in particular, for the cuffs of hydraulic drives. The properties of UHMWPE are considered, in comparison with other types of polyethylene. | Using Ultrahigh-Molecular-Weight Polyethylene in Hydraulic Drives | 10.3103/S1068798X20090208 |
2020-09-01 | The static-implicit finite element method was used to simulate the low plasticity ball burnishing process using two-dimensional (2-D) and three-dimensional (3-D) models. The simulations were performed using an elastic-rigid strain hardening plastic flow model. The residual stress distribution along the surface layer of the Ti6Al4V thin sheet is predicted, and the results are compared with limited experimental data from the industry. The simulated residual stresses matched with the measured ones in terms of trends; however, some deviations were observed for the peak and boundary values. The 2-D model is practical to construct, and the simulations are fast; however, it does not provide the planar stress distribution. The 3-D model is more realistic, yet still very sensitive to boundary conditions as well as friction. More realistic results are possible with large models where the effects of boundary conditions get weaker. | Prediction of residual stresses in ball burnishing TI6AL4V thin sheets | 10.1007/s00170-020-05837-2 |
2020-09-01 | The low-grade siliceous chromite ore from Ghutrigaon, Odisha, India, containing ~ 16% Cr 2 O 3 , with Cr/Fe ratio of 1.97 and ~ 55% of SiO 2 , does not find any use in metallurgical industry and hence considered as waste. Mineralogical investigation indicates the presence of chromite and quartz as major minerals with minor fuchsite and kaolinite. The beneficiation studies reveal that the product can be enriched to a Cr/Fe ratio of 3.35 and 3.02 by gravity concentration (wet shaking table) and wet high intensity magnetic separation, respectively. Tiny Cr-grains within quartz and fine silica dusts within chromite inhibit liberation of chromite resulting in poor response to physical beneficiation. As an alternative, processing of ore through pyro-metallurgical route was evaluated. Chromite fines mixed with carbon and lime in the form of pellets/granules was charged to a plasma reactor. In about ten minutes, the metal globules/prills were separated from the slag in 1:6 ratio. The metal, examined through XRD and optical microscope, was found to be ferrochrome alloy. In situ EDAX analysis indicated the metal to have 61.51% Cr, 26.52% Fe and 13.1% C with minor silica (2.42%), and the slag was composed of Ca 2 Al 2 SiO 7 which revealed that both metal and slag so obtained could suitably be used in different industries. | Processing of Low-Grade Chromite Ore for Ferroalloy Production: A Case Study from Ghutrigaon, Odisha, India | 10.1007/s12666-020-02032-5 |
2020-09-01 | Abstract Optimization criteria are proposed for processes of separating ethylene and propylene from a mixture of low-boiling gases. These criteria are based on the physicochemical properties of substances and take into account special techniques used for separating such mixtures. Unlike the existing criteria based on considering the heat input to the reboiler and the heat output from the condenser of a distillation column, these optimality criteria more accurately evaluate the economic performance of the process, because they include the refrigerant preparation cost, which plays a decisive role in separating low-boiling gases. Four known methods of separating mixtures of low-boiling gases are considered: (A) separation in a column with steam as the heat-transfer medium in the column reboiler and with a refrigerant in the condenser, (B) separation in a column with the condensation of the vapor of a refrigerant in the column reboiler and with the same refrigerant in the condenser, (C) separation in a column with the condensation of the vapor of the i th refrigerant in the column reboiler and with the j th refrigerant in the condenser, and (D) separation in a column with steam as a heat-transfer medium in the column reboiler and with recirculating water in the condenser. Parameters that are expediently used as optimality criteria are identified. New approaches to creating the optimal processes of separating low-boiling gases are developed and theoretically justified for further implementation. | Developing Optimization Criteria for Processes of Separating Low-Boiling Gases | 10.1134/S0040579520050024 |
2020-09-01 | Abstract This article describes an approach to evaluating the resource of automatic coupler bodies against the criteria of the metalwork strain damage rate. The results of this study are used to analyze the resource life of an automatic coupler body, including determination of its safe operation life. | The Modeling Burden and Resource of an Automatic Coupler Body by Techniques of Numerical Analysis | 10.3103/S105261882005009X |
2020-09-01 | Taxonomic complexities, like environmental plasticity and homoplasy, make precise identification challenging in Calamus , the genus of spiny climbing palms of the subfamily Calamoideae (Arecaceae). In the present study, the species discriminatory power of twelve potential DNA barcode regions ( rbc L, mat K, psb A- trn H, rpo C , rpo B , psb K- psb I , atp F- atp H, psb Z- trnf M, ITS1, ITS2, PRK, and RPB2) were evaluated in 21 species of Calamus from the Western Ghats region of India, using distance, tree, and similarity based statistical methods. Except for the low copy nuclear region, RPB2, none of the tested plastid loci or nuclear loci ITS, either singly or in combinations, could discriminate all the species of Calamus due to low substitution rate of plastid regions and multiple copies of ITS respectively. The RPB2 locus showed highest species resolution with 96% accuracy in similarity based analysis, indicating its potential and efficiency as a barcode locus for the genus. The putative “ Calamus gamblei complex” based on overlapping morphology was successfully resolved as six distinct, though closely related, species. The analysis also indicates that C. delessertianus is a morphological variant of C. dransfieldii. In spite of being a low copy nuclear gene region, RPB2 provided an efficient barcode to delineate Calamus species and has the potential to further extend its use as a prospective barcode to other Palm genera. | The low copy nuclear region, RPB2 as a novel DNA barcode region for species identification in the rattan genus Calamus (Arecaceae) | 10.1007/s12298-020-00864-5 |
2020-09-01 | Abstract The formation of thin nanoscale films of metal silicides Me Si ( Me : Li, Rb, K and Cs) is studied by electron spectroscopy techniques, scanning electron microscopy, and slow electron diffraction. As a result of the high dose (10 17 cm –2 ) implantation of low-energy (5 keV) Li, Rb, K and Cs ions into Si(111) and Si(100) single crystals and short-term thermal annealing, LiSi, RbSi, CsSi, KSi single-crystal silicide films are created in the silicon surface region. The optimal modes of ion implantation and annealing were determined for the formation of thin single-crystal films of metal silicides. The thickness of the silicide films is shown to increase with increasing energy of implanted ions and at a fixed energy to be proportional to the square root of the ion dose. | Structure of МеSi Silicide Films (Me: Li, Rb, K and Cs) According to Electron Microscopy Data and the Diffraction of Slow Electrons | 10.1134/S1027451020050365 |
2020-09-01 | Activation of glial cells (including microglia and astrocytes) appears central to the initiation and progression of neuroinflammation in Alzheimer’s disease (AD). The low-density lipoprotein receptor-related protein 1 (LRP1) is a major receptor for amyloid-β (Aβ), which plays a critical role in AD pathogenesis. LRP1 regulates inflammatory response by modulating the release of pro-inflammatory cytokines and phagocytosis. However, the effects of LRP1 on microglia- and astrocytic cell-mediated neuroinflammation and their underlying mechanisms in AD remain unclear. Therefore, using APP/PS1 transgenic mice, we found that LRP1 is downregulated during disease progression. Silencing of brain LRP1 markedly exacerbated AD-related neuropathology including Aβ deposition, neuroinflammation, and synaptic and neuronal loss, which was accompanied by a decline in spatial cognitive ability. Further mechanistic study revealed that silencing of LRP1 initiated neuroinflammation by increasing microgliosis and astrogliosis, enhancing pro-inflammatory cytokine production, and regulating toll-like receptor 4 (TLR4)-mediated activation of nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) signaling pathways. Taken together, these findings indicated that LRP1 suppresses microglia and astrocytic cell activation by modulating TLR4/NF-κB/MAPK signaling pathways. Our results further provide insights into the role of LRP1 in AD pathogenesis and highlight LRP1 as a potential therapeutic target for the treatment of AD. | Silencing of LRP1 Exacerbates Inflammatory Response Via TLR4/NF-κB/MAPKs Signaling Pathways in APP/PS1 Transgenic Mice | 10.1007/s12035-020-01982-7 |
2020-09-01 | Abstract A low-velocity vertical impact method was considered on various composite specimens. Impact damage areas were studied by the ultrasonic echo-pulse method, the damage size dependence on impact energy was determined in various polymer composite materials. Damaged specimens were tested in compression to determine their residual strength. Layer-by-layer assessment of damage was carried out for a set of specimens by the computed tomography. | The Study of Strength of Composites under Impact | 10.3103/S1068799820030046 |
2020-09-01 | Fluoride is an essential trace element for humans, and its deficiency or excess in the environment could lead to disease. To investigate the spatial distribution and health risk assessment of fluoride (F − ) in drinking water, 302 tap water samples from Chongqing urban areas, China, were collected to analyze F − using an ion chromatograph. The results showed that (1) F − concentration in drinking water ranged from 0.100 to 0.503 mg/L, with an average of 0.238 ± 0.045 mg/L. (2) The spatial autocorrelation analysis showed that high–low clusters were mostly located in Dadukou District and Beibei District, while low–low clusters were mainly in southern Banan District. (3) The fluoride average daily doses of children, teens and adults were 0.030, 0.029 and 0.031 mg/(kg day). (4) Hazard quotients of excessive fluoride (HQ e ) of children, teens and adults were 0.51 ± 09, 0.49 ± 0.09 and 0.52 ± 0.10, respectively (inferior to 1.00), whereas hazard quotients of inadequate fluoride (HQ i ) of those groups were 1.21 ± 0.26, 1.23 ± 0.26 and 1.15 ± 0.25, respectively (superior to 1.00). Therefore, average daily fluoride intake of residents with drinking water was inadequate. This could pose dental caries and osteoporosis threats for residents from Chongqing urban areas. | Spatial variation and health risk assessment of fluoride in drinking water in the Chongqing urban areas, China | 10.1007/s10653-020-00532-3 |
2020-09-01 | Low-abundance proteins (LAPs) play a very important role in interaction, regulation, and metabolism of plant biological processes. A combinatorial peptide ligand library (CPLL) can solve the problem of high-abundance proteins (HAPs) masking LAPs and enlarging the dynamic range of protein concentrations perfectly and be considered as one of the most advanced approaches for plant proteomics research. In this paper, a proper CPLL method to rice leaf proteins was established for the first time and 1056 proteins were identified in rice leaf extracts, and 624 (59.1%) LAPs were newly detected after CPLL. Based on this technology, we detected the response of rice to Cd stress and analyzed the differential LAPs and the biological significance of misexpressed proteins before and after Cd stress by bioinformatics analysis. An important contribution has also been made to a better understanding of the complex mechanisms by which rice adapts to Cd stress. Graphical abstract | Insight of low-abundance proteins in rice leaves under Cd stress using combinatorial peptide ligand library technology | 10.1007/s00216-020-02760-z |
2020-09-01 | Abstract Optimal formulations of low-viscosity marine fuel (LMF) involving heavy diesel fractions of secondary origin and containing cold flow improvers and antioxidants have been found by mathematical modeling using the pour point, sulfur content, and density as critical parameters. The experimentally obtained characteristics of laboratory LMF samples prepared according to the calculated formulations correlate well with theoretical data and comply with the requirements of regulatory documents. The possibility of involving heavy distillates, produced by Angarsk Petrochemical Company, in LMF is shown. The antioxidant Kerobit TP 26 P is proposed as a stabilizer in the production of LMF composed of a heavier diesel fraction from the atmospheric column of the GK-3 unit and the atmospheric–vacuum distillation residue of the hydrogenated product from units for hydrotreating of heavy middle-distillate fractions of primary and secondary oil refining. The effectiveness of the antioxidant has been evaluated in terms of change in total sediment, which is a measure of oxidative stability, as well as by the existent gum content. The EPR technique has proved the occurrence of radical reactions during storage of heavy diesel fractions of secondary origin and the inhibitory effect of Kerobit-TP 26 P on these processes. | Low-Viscosity Marine Fuel Based on Heavy Diesel Fractions of Secondary Origin: Problems and Solutions | 10.1134/S0965544120090030 |
2020-09-01 | Phosphorus (P) is one of the essential macronutrients for rice. In this study, we used 120 rice backcross recombinant inbred lines (BRILs) derived from a cross indica cv. Changhui 891 and japonica cv. 02428. To elucidate the genetic control of P deficiency tolerance in rice, we have used high quality SNPs bin markers to identify some important loci underlying phosphorus deficiency. The bin map was generated which includes 3057 bins covering distance of 1266.5 cM with an average of 0.41 cM between markers. Based on this map, 50 loci, including four novel loci, qSL - 3 , qRL - 11 , qSDW - 1 , qRDW - 1 with phenotypic variance 23.26%, 12.06%, 9.89% associated with P deficiency-related seedling traits were identified. No significant QTLs was found for root length under P+, shoot fresh weight P− and root length, shoot fresh weight for P+, P− and their ratio respectively. Root fresh weight, and root dry weight were strongly correlated to each other, and QTLs for these variables were located on the same chromosome 1 at the same region. Notably, 3 pleiotropic regions is the pioneer of our study, and these regions would facilitate map-based cloning to expedite the MAS selection for developing low phosphorous tolerant varieties. This study not only improves our knowledge about molecular processes associated with P deficiency, but also provides useful information to understand the genetic architecture of low phosphorous tolerance. | Genetic mapping and identification of new major loci for tolerance to low phosphorus stress in rice | 10.1007/s12298-020-00858-3 |
2020-09-01 | Environmental cues like noise, pressure, and circadian rhythm can affect the hearing ability of human beings. Nevertheless, the complex physiology of the human being does not allow us to understand how these factors can affect hearing and hearing-related behaviors. Conversely, these effects can be easily checked using the hearing organ of Drosophila melanogaster , the Johnston organ. In the current study, the Drosophila was exposed to challenging environments like noise, low pressure, and altered circadian rhythm. The hearing organ of larvae, as well as adults, was analyzed for hearing-related defects. In the third instar larva, the cell deaths were detected in the antenna imaginal disc, the precursor of Johnston’s organ. Elevated levels of reactive oxygen species and antioxidant enzymes were also detected in the adult antennae of environmentally challenged flies. The ultrastructure of the antennae suggests the presence of abundant mitochondria in the scolopidia of control. Fewer amounts of mitochondria are found in the environmentally challenged adult antennae. In adults, various hearing-related behaviors were analyzed as a readout of functionality of the hearing organ. Analysis of climbing, aggressive, and courtship behaviors suggests abnormal behavior in environmentally challenged flies than the control. The current study suggests that the environmental cues can alter hearing-related behaviors in Drosophila . The methods used in this study can be used to monitor the environmental pollution or to study the effect of alteration of noise, pressure, and circadian rhythm on hearing-related behaviors taking Drosophila melanogaster as a model organism. Graphical abstract | Environmental cue affects the hearing-related behaviors of Drosophila melanogaster by targeting the redox pathways | 10.1007/s11356-020-09141-0 |
2020-09-01 | Group-1 homoelog genes in wheat genomes encode storage proteins and are the major determinants of wheat product properties. Consequently, understanding the genetic diversity of group-1 homoelogs and genes encoding storage proteins, especially the low-molecular-weight glutenins (LMW-GSs), within wheat landrace genomes is necessary to further improve the quality of modern wheat crops. The genetic diversity of group-1 homoelogs in 75 Xinjiang winter wheat landraces was evaluated by Diversity Arrays Technology (DArT) markers. These data were used to select 15 landraces for additional LMW-GS gene isolation. The genetic similarity coefficients among landraces were highly similar regardless if considering the diversity markers on 1A, 1B, and 1D chromosomes individually or using all of the markers together. These similarities were evinced by the generation of four similar cluster dendrograms that comprised 11–15 landrace groups, regardless of the dataset used to generate the dendrograms. A total of 105 LMW-GS sequences corresponding to 79 unique genes were identified overall by using primers designed to target Glu-A3 and Glu-B3 loci, and 54 mature proteins were predicted from the unique LMW-GS genes. Nine novel chimeric LMW-GS genes were also identified, of which, one was recombinant for -i/-m, one for -s/-m, and seven for -m/-m parent genes, respectively. Phylogenetic analysis separated all of the LMW-GSs into three clades that were supported by moderate bootstrap values (> 70%). The clades corresponded to LMW-GS genes primarily harboring different N-terminals. These results provide useful information for better understanding the evolutionary genetics of the important Glu-3 locus of wheat, and they also provide new novel gene targets that can potentially be exploited to improve wheat quality. | The genetic diversity of group-1 homoeologs and characterization of novel LMW-GS genes from Chinese Xinjiang winter wheat landraces (Triticum aestivum L.) | 10.1007/s13353-020-00564-6 |
2020-09-01 | The paper deals with the dislocation and dislocation-disclination substructures of polycrystalline FCC alloys Cu–Al and Cu–Mn modified by tensile deformation. Observations are performed using the transmission electron microscopy. It is shown that the grain size of the alloy structure ranging from 10 to 240 μm, can serve as a critical parameter in the low-stability state during the deformation and transition from one stage of hardening to another. The dependences are obtained for the parameters describing the defect substructure and the mean grain size. These dependences are compared with the structure and phase composition of the alloys. The critical grain size of about 100 μm is found at a meso-level. When the grain size exceeds 100 μm, the main role in defect accumulation play intracrystalline processes. At stage II, the strain-hardening coefficient does not depend on the grain size of >100 μm and rapidly increases at a grain size of <100 μm. | Critical Grain Size at Meso-Level after Deformation of Polycrystalline Metals and Alloys in Low-Stability State | 10.1007/s11182-020-02097-1 |
2020-09-01 | Abstract In the present work, copper(II) oxide nanoparticles were prepared using simple and low-cost from calcination of CuSO 4 or Cu(OAC) 2 at the presence of polyvinyl alcohol (PVA) in a weight ratio of 1 : 1 at 600°C for 3 h. The basic properties of CuO nanoparticles were described by Fourier Transform Infrared (FT-IR) spectroscopy, powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). All results confirmed that the as-prepared copper(II) oxide nanoparticles were pure with high degree of crystallinity and that resulting shape, size and morphology of nanoparticles were depending on the applied precursor. In addition, the antibacterial activity of CuO-1 and CuO-2 nanoparticles was performed on Gram-negative E. coli and P. aeruginosa using disc diffusion method cultures throughout at 24 h period. Antibacterial results demonstrated that the as-prepared CuO nanoparticles act as effective bacterial agents. | Synthesis, Characterization, and Antibacterial Activity of Copper(II) Oxide Nanoparticles Prepared by Thermal Decomposition | 10.1134/S1027451020050109 |
2020-09-01 | Abstract Preore metasomatites of epithermal gold–silver deposits are formed by various types of hydrothermal solutions—from highly acidic and oxidized (argillization, alunitization, secondary quartzites) and moderately acid (sericitization) to rather reduced and alkaline (adularia). The possible processes creating highly acid mineralizing fluids at shallow depths are: (a) the condensation of the acid gas phase of heterogenized fluids (including also the condensation of gaseous HCl, HF and H 2 SO 4 whose water solutions possess properties of maximum boiling azeotropic mixtures); (b) the oxidation of containing SO 2 and H 2 S magmatogene gases by meteoric waters rich in oxygen; and also c) possible disproportionation of sulfur from SO 2 to H 2 S and H 2 SO 4 . The epithermal gold–silver deposits of high sulfidation type form at the upper parts of heterophase fluid systems. The major gold–silver and sulfide mineralization (except small amounts of earlier generations of pyrite, enargite, and luzonite) precipitates not synchronously with the acid metasomatites, but essentially later, when the water table of liquid and less acid fluids raise into the realm of ore deposition. At zones of flat subducting ocean crust, the deposits of copper–porphyry type are quite often found beneath the epithermal Au–Ag deposits. However, the former cannot be considered the bottom of the gold–silver ore-forming systems, because they sometimes form much earlier and in closed systems; therefore, they have their own bottom part of the ore-forming system (a zone of K-feldspathization with related molybdenum ore) and the top part (a zone of sericitization with related copper mineralization). In addition, in steep subduction zones typical of the Central West Pacific region, including Khabarovsk and Primorsky krais and Japan, epithermal Au–Ag deposits have no spatial or temporal relations to copper–porphyry deposits due to the nearly complete absence of the latter. There are the alkaline metasomatites that form in the lower, bottom parts of epithermal heterophase fluid systems, creating the major bonanza gold–silver and sulfide mineralization of the adularia ( low sulfidation ) type in the Russian Far East, western America, and Japan. The term high sulfidation widely used now was created by the artificial combination of the terms high sulfate and high oxidation and is very ambiguous, because it really does not imply sulfidization processes. This type of mineralization would be better named acid sulfate. | Formation Environments of Metasomatites and Ores of the Epithermal Gold–silver Deposits | 10.1134/S1075701520050037 |
2020-09-01 | This paper presents an optimum design of an ultra-wideband (UWB) 2.5–10.5-GHz low-noise amplifier (LNA) in 180-nm and 65-nm radiofrequency (RF)-complementary metal–oxide–semiconductor (CMOS) technology. A novel input matching network employing resistive–inductive feedback and a noise-canceling technique is proposed to achieve broadband matching as well as a low noise figure (NF). Moreover, a current-reused structure and the inductive peaking technique are applied in the proposed LNA to reduce its power consumption and provide high, flat gain. The proposed UWB-LNA is optimized using heuristic multiobjective optimization based on inclined planes system optimization (IPO) and particle swarm optimization (PSO) as simulation-based evolutionary techniques. The proposed UWB-LNA is designed and simulated using HSPICE and Cadence Spectre RF. The postlayout simulation results show an input return loss ( S 11 ) of less than −10 dB, a flat power gain ( S 21 ) of 13.2 ± 0.5 and 14 ± 0.5 dB, and an NF below 5 and 2.5 dB over the whole UWB band when implemented in 180-nm and 65-nm CMOS technology, respectively. The UWB-LNA consumes 7.2 and 9.5 mW from a 1.8-V power supply when implemented in 180-nm and 65-nm CMOS technology, respectively. | Optimum design of a new ultra-wideband LNA using heuristic multiobjective optimization | 10.1007/s10825-020-01513-6 |
2020-09-01 | Abstract Geological records of the Matuyama–Brunhes (M–B) geomagnetic reversal facilitate the development of an age model for sedimentary and volcanic sequences and help decipher the dynamics of the Earth’s magnetic field. However, the structure of the geomagnetic field during the M–B geomagnetic reversal remains controversial due to its complex field behavior. In this study, we conducted paleo- and rock-magnetic analyses of samples from the Chiba composite section (CbCS), a continuous and expanded marine succession in Central Japan, to reconstruct the full sequence of the M–B geomagnetic reversal. We define an average stratigraphic position of the M–B boundary and estimate its age based on three sections in the CbCS and a neighboring drill core, TB-2. The average stratigraphic position of the M–B boundary in the CbCS is established at 1.1 ± 0.3 m above a widespread volcanic ash bed (the Byk-E tephra). Assuming a chronological error associated with orbital tuning of 5 kyr and stratigraphic uncertainty of 0.4 kyr, the M–B boundary in CbCS is at 772.9 ± 5.4 ka (1σ). The virtual geomagnetic pole, which is calculated from the paleomagnetic directions, shows several short fluctuations between 783 and 763 ka, with concomitant decreases in geomagnetic field intensity index. After termination of the field instabilities, the field intensity recovered and became higher than before the M–B boundary, with a stable normal polarity direction. The paleomagnetic records in the CbCS exhibit a field asymmetry between the axial dipole decay and field recovery, providing a full sequence of the M–B reversal, suggesting that the non-axial dipole field dominated several times during periods ca. 20 kyr long across the M–B boundary, due to depletion in the main axial dipole component. Our results provide probably the most detailed sedimentary record of the M–B geomagnetic reversal and offer valuable information to further understand the mechanism and dynamics of geomagnetic reversals. Graphical abstract | A full sequence of the Matuyama–Brunhes geomagnetic reversal in the Chiba composite section, Central Japan | 10.1186/s40645-020-00354-y |
2020-09-01 | Background The glove single-port laparoscopic appendectomy is a novel single incision laparoscopic technique (SILT) which is extremely cheaper than the other commercial devices. Objective This study aimed to compare conventional laparoscopic appendectomy (CLA) and glove single port laparoscopic appendectomy (GSPLAP) in adolescents performed under spinal anaesthesia (SA ). Patients and Methods Forty-eight adolescents with uncomplicated appendicitis were included in the current study. All patients were randomized into 2 groups. Group A was operated upon by GSPLAP and group B, was operated upon using CLA. All cases were done under SA. Results Forty-eight adolescents were treated either by GSPLAP or LAP during the period from September 2017 to August 2018. They were 30 males and 18 females with a mean age 14.8 ± 2.2 years (range = 12–18 years). All procedures were completed laparoscopically without conversion. Only 2 cases of group A were converted to CLA. The mean operative time was 35.14 ± 12.14 min (range = 26–80 min) for CLA and 50.3 ± 11.2 min (range = 40–88 min) for GSPLAP. SA was successful in 44 cases [91.7%], while 4 patients [8.3%] were converted to general anaesthesia [GA]. Post SA headache was reported in 3 cases. Post-operative umbilical cellulitis occurred in two cases. Conclusion Our modification of Glove Single Port is technically feasible. The GSPLAP is a new SILT which is cheaper than other single incision laparoscopic devices in the market. This study proved that SA for laparoscopic appendectomy (LAp) is a good substitute of GA in adolescents. | Modified glove single-port laparoscopic appendectomy versus conventional laparoscopic appendectomy in adolescent age under spinal anesthesia | 10.1007/s42804-019-00038-5 |
2020-09-01 | The aim of this study was to evaluate the osseointegration of implants placed in areas grafted with different osteoconductive bone substitutes irradiated with infrared low-level laser therapy (LLLT). Fifty-six rats were randomly allocated into 4 groups: DBB, bone defects filled with deproteinized bovine bone graft (DBB); HA/TCP, bone defects filled with biphasic ceramic made of hydroxyapatite and β-tricalcium phosphate (HA/TCP); DBB-L, bone defects filled with DBB and treated by LLLT; HA/TCP-L, bone defects filled with HA/TCP and treated by LLLT. Bone defects were performed in the tibia of each animal and filled with the different biomaterials. The grafted areas were treated with LLLT (λ 808 nm, 100 mW, ϕ ∼ 0.60 mm) in 7 sessions with 48 h between the irradiations. After the 60-day period, the implants were placed, and the animals were euthanized after 15 and 45 days. The osseointegration and bone repair in the grafted area were evaluated by biomechanical, microtomographic and histometric analyses, and the expression of some bone biomarkers was evaluated by immunohistochemistry analysis. LLLT induced higher degree of osseointegration, which was associated with the greater expression of BMP2 and OCN. LLLT performed in areas grafted with osteoconductive bone substitutes prior to implant placement improves osseointegration. | Low-level laser therapy (LLLT) in sites grafted with osteoconductive bone substitutes improves osseointegration | 10.1007/s10103-019-02943-w |
2020-09-01 | Phloroglucinol is a three-hydroxyl phenolic compound and has diverse physiological and pharmacological activities such as antivirus and anti-inflammatory activities. Chemical synthesis of phloroglucinol suffered from many drawbacks such as high cost and environmental pollution. To avoid the above issues, microbial phloroglucinol biosynthesis was successfully accomplished in this study, while the abundant and low-cost acetate was used as the main carbon source. Firstly, the toxicity of phloroglucinol was tested, and E. coli BL21(DE3) could tolerate 5 g/L phloroglucinol. The ability of phloroglucinol synthase (PhlD) for catalyzing malonyl-CoA to phloroglucinol was confirmed, and E. coli BL21(DE3) expressing PhlD and acetyl-CoA carboxylase (ACCase) could produce 1107 ± 12 mg/L phloroglucinol from glucose. Then, E. coli BL21(DE3) was engineered to utilize acetate to produce 228 ± 15 mg/L phloroglucinol. Then, the endogenous citrate synthase (GltA) which could catalyze oxaloacetate and acetyl-CoA generated from acetate to citrate was knocked down by CRISPRi system in order to enhance the carbon flux for phloroglucinol production, and the titer was improved to 284 ± 8 mg/L. This work demonstrated that acetate could be used as low-cost substrate to achieve the biosynthesis of phloroglucinol and provided an example of effective utilization of acetate. | Metabolic engineering of E. coli for producing phloroglucinol from acetate | 10.1007/s00253-020-10591-2 |
2020-09-01 | Atherosclerosis is a significant cause of mortality and morbidity. Studies suggest that the chemokine receptor CX3CR1 plays a critical role in atherogenesis. Shear stress is an important mechanical force that affects blood vessel function. In this study, we investigated the effect of shear stress on CX3CR1 expression in vascular endothelial cells (VECs). First, cells were exposed to different shear stress and then CX3CR1 mRNA and protein were measured by quantitative RT-PCR and western blot analysis, respectively. CX3CR1 gene silencing was used to analyze the molecular mechanisms underlying shear stress-mediated effects on CX3CR1 expression. CX3CR1 mRNA and protein expression were significantly increased with 4.14 dyne/cm 2 of shear stress compared with other tested levels of shear stress. We observed a significant increase in CX3CR1 mRNA levels at 2 h and CX3CR1 protein expression at 4 h. CX3CR1-induced VCAM-1 expression in response to low shear stress by activating NF-κB signaling pathway in VECs. Our findings demonstrate that low shear stress increases CX3CR1 expression, which increases VCAM-1 expression due to elevated NF-κB activation. The current study provides evidence of the correlation between shear stress and atherosclerosis mediated by CX3CR1. | Low Shear Stress Upregulates CX3CR1 Expression by Inducing VCAM-1 via the NF-κB Pathway in Vascular Endothelial Cells | 10.1007/s12013-020-00931-4 |
2020-09-01 | MCML (MOS Current Mode Logic) based implementation producing fast response and compliment output at the same time gives an impetus to the researcher to replace Bulk CMOS. Moreover, tremendous challenges faced by bulk CMOS at channel lengths below 45 nm induces a need to strive for a technological replacement of silicon in years to come. This introduces a zest in designer's mind to look for competent and novel substances to overcome the shortcoming of existing silicon. The future technology should be capable to deliver fast response, low power operation, scalable to reduced dimensions, and strong towards process variations. Carbon nanotube based technology (CNFET) is one of the reliable and competent alternative because it has most of these desired features and similar operating principle as that of CMOS. And hence, this research article focuses on a relative evaluation of CMOS and CNFET version of 3 bit parity checker at 16-nm technology nodes. The CNFET based 3 bit parity checker is faster (9.75×), it offers improvement in power dissipation (11.93×), improvement in PDP (116.39×), improvement in EDP (1135.76×) compared to CMOS counterpart. Scaling down the device emerges with a challenge of variability, just as power, delay and area, variability also has an impact on performance of the circuit. Technology scaling has significant consequences such as wider variation. This research article also presents variability analysis, in terms of delay (t p ) and power-delay product ( PDP ) for the proposed CNFET based MCML 3 bit Parity checker circuit. Extensive simulation using 16-nm technology node are carried out by loading two nominal copies of 'CNFET based MCML 3 bit Parity checker' (Circuit under Test) at either ends—input and output. This simulation framework supports the high level integration where stand alone operation has no application in the industry. The intent of this research is to investigate the circuit with minimal variability to propagation delay and PDP. The proposed ‘ CNFET based MCML 3 bit parity checker ’ exhibits improvement in delay (14.01×) and improvement in PDP (242.1×) variability as compared to CMOS counterpart. Thus, the CNFET based implementation emerges out as a robust circuit showing narrower spread in variability analysis against applied V DD . | Ultra high speed and novel design of power-aware CNFET based MCML 3-bit parity checker | 10.1007/s10470-020-01609-w |
2020-09-01 | There was few studies using the simultaneous reduction of fat and sodium chloride, as well as the stability of the meat products with these reductions. This study aimed to evaluate the effects of fat and sodium chloride reduction in beef burgers during storage. For this, two treatments were produced: T1—without fat and sodium chloride reduction (control) and T2—with 50% fat reduction + 5% fructooligosaccharides and with the replacement of 50% of sodium chloride by potassium chloride. Physicochemical analysis and sensory acceptance were performed. According to results, the pH increased ( p < 0.05) with 120 days. For the lipid oxidation, there was an interaction between treatments and storage. There was an increase in TBARS with storage for both treatments. T2 had the highest TBARS at 0, 30, and 60 days. For the color before cooking, there was a reduction in the redness ( p < 0.05) with 90 days. After cooking, the lightness reduced at 90 days, while the redness increased at 90 days. However, the instrumental changes were not perceived by consumers. For the sensory acceptance, there was a reduction in the flavor, texture and overall liking with storage. However, despite the decline, the averages remained in the acceptance zone. The beef burgers were perceived as less juiciness and less salty after storage. Thus, the storage affects the physicochemical characteristics and sensory evaluation of beef burgers low-fat and low-sodium. The results reinforce the need for more studies with the storage of meat products with fat and sodium chloride reduced. | Storage of beef burgers containing fructooligosaccharides as fat replacer and potassium chloride as replacing sodium chloride | 10.1007/s13197-020-04354-0 |
2020-09-01 | MiR-223 is closely associated with pathogenesis of coronary artery disease (CAD); however, the molecular mechanisms are unclear. In the present study, the human vascular endothelial cells (ECs) were isolated from patients undergoing coronary artery bypass graft and treated with oxidized low-density lipoprotein (ox-LDL) to induce cellular CAD models in vitro. We found that ox-LDL inhibited cell proliferation and viability, and promoted cell apoptosis in ECs. Of note, ox-LDL promoted cell pyroptosis, and both the pyroptosis inhibitor necrosulfonamide (NSA) and NLRP3 ablation restored cell viability in ECs treated with ox-LDL, indicating that ox-LDL induced EC death by triggering cell pyroptosis. In addition, miR-223 was downregulated by ox-LDL in ECs, and miR-223 overexpression rescued cell viability in ECs treated with ox-LDL. Interestingly, there existed targeting sites in miR-223 and 3′ untranslated regions (3′ UTRs) of NLRP3 mRNA, and further experiments validated that miR-223 negatively regulated NLRP3 expressions in ECs at both transcriptional and translational levels. Finally, we verified that upregulation of NLRP3 abrogated the protective effects of miR-223 overexpression on ox-LDL-treated ECs. Collectively, this in vitro study proved that overexpression of miR-223 protected ox-LDL-stimulated ECs from death through inactivating NLRP3 inflammasome-mediated pyroptotic cell death. | Upregulation of miR-223 abrogates NLRP3 inflammasome-mediated pyroptosis to attenuate oxidized low-density lipoprotein (ox-LDL)-induced cell death in human vascular endothelial cells (ECs) | 10.1007/s11626-020-00496-9 |
2020-09-01 | As a new type of computing, cloud computing has led to a major computational change. Among many technologies in cloud computing, task scheduling has always been studied as a core issue by industry and academia. In the existing research, the main goal is completion time or load balancing. However, as the expansion of cluster size, energy consumption becomes a problem that must be faced. In this paper, the first of maximum loss scheduling algorithm is proposed. The algorithm is a low-power algorithm that can greatly reduce the energy consumption of cloud computing clusters through loss comparison rule. The effect of this method is more obvious as the cluster size and the number of tasks increase. Experimental simulation results show that the proposed method is significantly better than the Max–Min, Min–Min, Sufferage and E-HEFT algorithms. Compared to Min–Min, Max–Min, Sufferage and E-HEFT algorithms, average completion time of the algorithm reduces 16%, 12%, 8% and 14%, respectively. At the same time, the load balancing effect is also better than Min–Min and Sufferage algorithms. | A low-power task scheduling algorithm for heterogeneous cloud computing | 10.1007/s11227-020-03163-8 |
2020-09-01 | Hydrologic characteristics including extreme-flow events in many rivers around the world have been altered due to the climate change and human activities. Most available research concerns about the extreme event trend, frequency and duration in a single river rather than the synchronicity or coincidence probability among different tributaries. Accurately knowing the coincidence probability of hydrologic extreme-flow events is vital for better water resources allocation and project design. Joint distribution constructed by the copulas function is a widely used method to conduct this issue. However, studies conducted by the copulas function are mostly carried out in a bivariate environment and ignore the nonstationary. These may not comprehensively reflect the hydrologic characteristics under the changing environment. This paper analyzes the related hydrologic low-flow changes considering the nonstationary under the changing environment in the Wei River Basin, China, where the climate tends to be drier. These analyses are obtained by using trivariate copulas function and Kendall’s return period method to derive the joint distribution of hydrologic low-flow in a seasonal time scale. The results mainly show that the coincidence probabilities of low-flow among three tributaries of the Wei River in four seasons after the change point are basically higher than those before the change point. It may indicate that the low-flow negative impacts in the whole Wei River Basin in four seasons may be intensified (which needs to be paid more attention) under the changing environment. | Coincidence probability analysis of hydrologic low-flow under the changing environment in the Wei River Basin | 10.1007/s11069-020-04051-3 |
2020-09-01 | The results of an expert survey of 1024 ground dams of class IV located in the Moscow Region were processed by the methods of the system theory of reliability. Exponential curves for unsatisfactory and dangerous safety levels retained by structures are constructed. The period during which the dam safety level will decrease and the number of dams, the safety level of which will decrease by an order of magnitude, are estimated. Using Markov analysis, a probabilistic forecast of the dam’s compliance with each safety level over time was made. A method for calculating the recovery frequency of the safety level of low-head ground dams is proposed. | The Failure Rate of Low-Head Ground Dams of Dangerous and Unsatisfactory Safety Level | 10.1007/s10749-020-01213-y |
2020-09-01 | Abstract In this publication, the discussion is focused on issues related to the stratigraphy and chronology of the Karama Lower Paleolithic site in the Altai Mountains in light of the article “Debatable Aspects of Initial Human Colonization of Siberia and Age of the Karama Site in the Altai Mountains” by V.S. Zykin, V.S. Zykina, and L.G. Smolyaninova published in Stratigraphy and Geological Correlation in 2016. | Comments on the “Debatable Aspects of Initial Human Colonization of Siberia and Age of the Karama Site in the Altai Mountains” by V. S. Zykin, V. S. Zykina, and L. G. Smolyaninova | 10.1134/S0869593820050056 |
2020-08-31 | Time dependent low-velocity single and multiple impact response of functionally graded (FG) untwisted and pretwisted conical shells are analysed considering porosity factor. A modified Hertzian contact law which accounts for permanent indentation is considered for the low velocity impact problem. An eight-noded isoparametric shell element is used for the finite element formulation while Newmark’s time integration algorithm is used to solve the time dependent equations. The effects of porosity considering even and uneven porosity factor, initial velocity of impactor ( VOI ), mass of the impactor and twist angle of FG conical shell on the transient impact response of the conical shell are examined and analyzed. The contact force and indentation increase with increase of VOI and mass of the impactor while the contact duration decreases for both the occasions. Twist angle has a significant effect on contact force but has marginal effect on contact duration. Contact force for perfect (porosity free) FG conical shells is higher than that of porous FG conical shells. Lower contact force is observed for higher porosity factor. Even porous FG conical shell predicts lower contact force and higher shell displacement than that of an uneven porous FG conical for a given porosity factor. | Time dependent response of impact induced functionally graded conical shell considering porosity | 10.1007/s12046-020-01455-6 |
2020-08-29 | This article examines the development of a low-cost and portable set-up controlled by an Arduino board to perform Reflectance Transformation Imaging technique, from the information derived from 45 digital photographs of an object acquired using a stationary camera. The set-up consists of 45 high-intensity light emitting diodes (LEDs) distributed over a hemispherical dome of 70 cm in diameter and a digital camera on the top of the dome. The LEDs are controlled by an Arduino board, and the user can individually control the LEDs state (ON or OFF) and duration of illumination. An old manuscript written with iron-gall ink and a set of 1 Euro coins mint in 2002 were photographed with the set-up. The interactive re-lighting and the mathematical enhancement of the object’s surface revealed corrosion, loss of material, scratches and other details, which were not perceived in standard images. These unique features, which can be extracted using edge detection processing, have immediate application in different fields such as cultural heritage or forensic studies, where they can be used as fingerprints to identify unique objects, allowing also recognizing the use of tools to alter the surface of coins to increase the price in the market. | Arduino-controlled Reflectance Transformation Imaging to the study of cultural heritage objects | 10.1007/s42452-020-03343-4 |
2020-08-28 | 166.6-MHz quarter-wave $$\beta =1$$ β = 1 superconducting cavities have been adopted for the High Energy Photon Source, a 6-GeV diffraction-limited synchrotron light source currently under construction. A large helium jacket was required to accommodate the enlarged cavity beam pipe for the heavy damping of higher-order modes; the original electric-probe pickup thus becomes inevitably long with unfavorable mechanical properties. Relocated to an existing high-pressure-rinsing port, a magnetic-loop pickup was designed, characterized by low radio-frequency and cryogenic losses and being multipacting-free and insensitive to manufacturing and assembly tolerances. The consequent removal of the original pickup port from the cavity largely simplified the helium jacket fabrication and may also reduce cavity contamination. This paper presents a comprehensive design of a low-loss magnetic-coupling pickup for quarter-wave $$\beta =1$$ β = 1 superconducting cavities. The design can also be applied to other non-elliptical structures. | Development of a low-loss magnetic-coupling pickup for 166.6-MHz quarter-wave beta
$$=$$
=
1 superconducting cavities | 10.1007/s41365-020-00795-6 |
2020-08-27 | Background The main purpose of this study is to investigate the effect of silodosin on the urodynamic consequences in a previously established model of lower urinary tract symptoms associated with benign prostate hyperplasia, the spontaneously hypertensive rats (SHR) supplemented with testosterone. Methods Three groups of animals (8-week-old; n = 10/group) were considered: Wistar Kyoto (control) rats (WKY), SHR supplemented with testosterone at 3 mg/kg/day and treated with either vehicle (SHR-T, n = 10) or silodosin at 0.1 mg/kg/day (SHR-T + silodosin, n = 10) by oral gavage for 6 weeks. Cystometry experiments were performed. The bladder was harvested, weighed and paraffin-embedded for morphometric analysis. The prostate was also harvested and weighed. Results The number of animals included in the analysis were n = 10/10 for WKY and n = 7–8/10 for each SHR rats supplemented with testosterone group. SHR-T displayed a significant decrease in the intercontraction interval, infused volume and mean flow rate whereas the frequency of non-voiding contractions was increased. Silodosin improved the voiding behavior of SHR-T by significantly increasing the intercontraction interval, the infused volume and the mean flow rate and decreasing the number of non-voiding contractions. SHR-T displayed a significant increase in prostate and bladder weights and a 15% increase in the detrusor wall area compared to WKY. Conclusions Chronic silodosin treatment relieved storage symptoms in SHR supplemented with testosterone and decreased the frequency of non-voiding detrusor contractions during the filling phase. | Silodosin improves functional consequences of lower urinary tract obstruction secondary to benign prostate hypertrophy, a proof of concept study in the spontaneously hypertensive rat supplemented with testosterone | 10.1186/s12894-020-00699-y |
2020-08-26 | Background Cardiovascular disease (CVD) is the leading cause of mortality worldwide. The effect of socioeconomic factors on cause-specific mortality and burden of CVD is rarely evaluated in low- and middle-income countries, especially in a rapidly changing society. Methods Original data were derived from the vital registration system in Yangpu, a representative, population-stable district of urban Shanghai, China, during 1974–2015. Temporal trends for the mortality rates and burden of CVD during 1974–2015 were evaluated using Joinpoint Regression Software. The burden was evaluated using age-standardized person years of life loss per 100,000 persons (SPYLLs). Age-sex-specific CVD mortality rates were predicted by using age-period-cohort Poisson regression model. Results A total of 101,822 CVD death occurred during 1974–2015, accounting for 36.95% of total death. Hemorrhagic stroke, ischemic heart disease, and ischemic stroke were the 3 leading causes of CVD death. The age-standardized CVD mortality decreased from 144.5/100,000 to 100.7/100,000 in the residents (average annual percentage change [AAPC] -1.0, 95% confidence interval [CI] -1.7 to − 0.2), which was mainly contributed by women (AAPC -1.3, 95% CI − 2.0 to − 0.7), not by men. Hemorrhagic stroke, the major CVD death in the mid-aged population, decreased dramatically after 1991. The crude mortality of ischemic heart disease kept increasing but its age-adjusted mortality decreased continually after 1997. SPYLLs of CVD death increased from 1974 to 1986 (AAPC 2.1, 95% CI 0.4 to 3.8) and decreased after 1986 (AAPC 1.8, 95% CI − 2.3 to − 1.3). These changes were in concert with the implementation of policies including extended medical insurance coverage, pollution control, active prophylaxis of CVD including lifestyle promotion, and national health programs. The mortality of CVD increased in those born during 1937–1945, a period of the Japanese military occupation, and during 1958–1965, a period including the Chinese Famine. Sequelae of CVD and ischemic heart disease are predicted to be the leading causes of CVD death in 2029. Conclusions Exposure to serious malnutrition in early life might increase CVD mortality in later life. Improvements in medical services, pollution control, and lifestyle could decrease CVD death. New strategy is needed to prevent the aging-related CVD death and burden in the future. | Associations of socioeconomic factors with cause-specific Mortality and burden of cardiovascular diseases: findings from the vital registration in urban Shanghai, China, during 1974–2015 | 10.1186/s12889-020-09390-1 |
2020-08-26 | The importance of the investigation of magnetic superstorms is not limited to academic interest, because these superstorms can cause catastrophic impact on the modern civilisation due to our increasing dependency on technological infrastructure. In this context, the Carrington storm in September 1859 is considered as a benchmark of observational history owing to its magnetic disturbance and equatorial extent of the auroral oval. So far, several recent auroral reports at that time have been published but those reports are mainly derived from the Northern Hemisphere. In this study, we analyse datable auroral reports from South America and its vicinity, assess the auroral extent using philological and astrometric approaches, identify the auroral visibility at − 17.3° magnetic latitude and further poleward and reconstruct the equatorial boundary of the auroral oval to be 25.1° ± 0.5° in invariant latitude. Interestingly, brighter and more colourful auroral displays were reported in the South American sector than in the Northern Hemisphere. This north–south asymmetry is presumably associated with variations of their magnetic longitude and the weaker magnetic field over South America compared to the magnetic conjugate point and the increased amount of magnetospheric electron precipitation into the upper atmosphere. These results attest that the magnitude of the Carrington storm indicates that its extent falls within the range of other superstorms, such as those that occurred in May 1921 and February 1872, in terms of the equatorial boundary of the auroral oval. | South American auroral reports during the Carrington storm | 10.1186/s40623-020-01249-4 |
2020-08-25 | Background Routine health information systems (RHISs) support resource allocation and management decisions at all levels of the health system, as well as strategy development and policy-making in many low- and middle-income countries (LMICs). Although RHIS data represent a rich source of information, such data are currently underused for research purposes, largely due to concerns over data quality. Given that substantial investments have been made in strengthening RHISs in LMICs in recent years, and that there is a growing demand for more real-time data from researchers, this systematic review builds upon the existing literature to summarize the extent to which RHIS data have been used in peer-reviewed research publications. Methods Using terms ‘routine health information system’, ‘health information system’, or ‘health management information system’ and a list of LMICs, four electronic peer-review literature databases were searched from inception to February 202,019: PubMed, Scopus, EMBASE, and EconLit. Articles were assessed for inclusion based on pre-determined eligibility criteria and study characteristics were extracted from included articles using a piloted data extraction form. Results We identified 132 studies that met our inclusion criteria, originating in 37 different countries. Overall, the majority of the studies identified were from Sub-Saharan Africa and were published within the last 5 years. Malaria and maternal health were the most commonly studied health conditions, although a number of other health conditions and health services were also explored. Conclusions Our study identified an increasing use of RHIS data for research purposes, with many studies applying rigorous study designs and analytic methods to advance program evaluation, monitoring and assessing services, and epidemiological studies in LMICs. RHIS data represent an underused source of data and should be made more available and further embraced by the research community in LMIC health systems. | Using routine health information data for research in low- and middle-income countries: a systematic review | 10.1186/s12913-020-05660-1 |
2020-08-24 | Background The prevalence of chronic constipation is increased in females and with age or environmental (low temperature), racial, socioeconomic, and habitual risk factors. The impact of low outside temperature on constipation drug use remains unclear. Here, we investigated risk factors for constipation drug use by evaluating data from the Japanese National Database. Methods This ecological study used the 2016 open Japanese National Database of health insurance claims (prescriptions) to acquire the number of health insurance prescription claims in all 47 prefectures for drugs to relieve constipation, antihypertensives, vasodilators, as well as medical check-ups and questionnaire responses. Internet survey on room temperatures in 2010 were also used. Pearson correlation coefficients (r) between the number of population-based prescriptions for each item were calculated and multiple linear regression analysis (MLR) was performed. Results Prescriptions for magnesium laxatives significantly correlated with aging ( r = 0.58), vasodilators ( r = 0.53), being female ( r = 0.43), antihypertensives ( r = 0.39), and inversely with eating ≤2 h before bedtime ( r = − 0.37), total crime rate ( r = − 0.33), insomnia ( r = − 0.33), and population density ( r = − 0.31). Stimulant laxatives (sennoside and picosulfate) were significantly correlated with antihypertensives ( r = 0.79), aging ( r = 0.69), vasodilators ( r = 0.67), and being female ( r = 0.56), and were inversely associated with average outside temperature ( r = − 0.62), total crime rate ( r = − 0.52), average income ( r = − 0.51), and 30-min of vigorous exercise ( r = − 0.44). Fecal interventions were significantly correlated with aging ( r = 0.55) and female ( r = 0.59), and inversely correlated with population density ( r = − 0.41) and total crime rate ( r = − 0.38). MLR analysis identified aging as the only significant risk factor for magnesium laxative use (partial slope [β] = 1241.0). Female sex and antihypertensives were independent risk factors for stimulant laxative prescriptions (β = 44,547.0 and 0.2) and average outside temperature and 30-min of vigorous exercise were independent preventive factors (β = − 616.8 and − 219.1). Conclusion We identified associations of magnesium laxatives with aging, stimulant laxatives with female sex, antihypertensives, low outside temperature and less 30 min of vigorous exercise. | Factors correlated with drug use for constipation: perspectives from the 2016 open Japanese National Database | 10.1186/s12876-020-01425-6 |
2020-08-24 | Background Most newborn deaths occur among those of low birthweight (LBWt), due to prematurity &/or impaired fetal growth. Simple practices can substantially mitigate this risk. In low-income country settings where many births occur at home, strategies are needed that empower mothers to determine if their babies are at higher risk and, if so, to take measures to reduce risk. Earlier studies suggest that foot-length may be a good proxy for birthweight. An earlier Nepal study found a 6.9 cm cut-off performed relatively well, differentiating normal from low birthweight. Methods Community-based, cluster-randomized controlled trial. Objective: to determine whether family-administered screening, associated with targeted messages improves care practices known to mitigate LBWt-associated risks. Participants: women participating in a parent trial in rural Nepal, recruited late in pregnancy. Women were given a 6.9 cm card to assess whether the baby’s foot is small; if so, to call a number on the card for advice. Follow-up visits were made over the 2 weeks following the birth, assessing for 2 behavioral outcomes: reported skin-to-skin thermal care, and care-seeking outside the home; assessed restricting to low birthweight (using 2 cutoffs: 2500 g and 2000 g). Randomization: 17 clusters intervention, 17 control. The study also documented performance along the presumed causal chain from intervention through behavioral impact. Results 2022 intervention, 2432 control. Intervention arm: 519 had birthweight < 2500 g (vs. 663 among controls), of which 503 were available for analysis (vs. 649 among controls). No significant difference found on care-seeking; for those < 2500 g RR 1.13 (95%CI: 0.97–1.131). A higher proportion of those in the intervention arm reported skin-to-skin thermal care than among controls; for those < 2500 g RR 2.50 (95%CI: 2.01–3.1). However, process measures suggest this apparent effect cannot be attributed to the intervention; the card performed poorly as a proxy for LBWt, misclassifying 84.5% of those < 2000 as normal weight. Conclusions Although the trial found an apparent effect on one of the behavioral outcomes, this cannot be attributed to the intervention; most likely it was a result of pure chance. Other approaches are needed for identifying small, at-risk babies in such settings, and targeting them for appropriate care messaging. Trial registration ClinicalTrials.gov NCT02802332 , registered 6/16/2016. | Community-based cluster randomized controlled trial: empowering households to identify and provide appropriate care for low-birthweight newborns in Nepal | 10.1186/s12889-020-09317-w |
2020-08-21 | Background Cardiac Ca 2+ /calmodulin-dependent protein kinase II (CaMKII) activation plays a critical role in cardiomyocyte (CM) apoptosis and arrhythmia. Functional ATP-sensitive potassium (K ATP ) channels are essential for cardiac protection during ischemia. In cultured CMs, L5 low-density lipoprotein (LDL) induces apoptosis and QTc prolongation. L5 is a highly electronegative and atherogenic aberrant form of LDL, and its levels are significantly higher in patients with cardiovascular-related diseases. Here, the role of L5 in cardiac injury was studied by evaluating the effects of L5 on CaMKII activity and K ATP channel physiology in CMs. Methods Cultured neonatal rat CMs (NRCMs) were treated with a moderate concentration (ie, 7.5 μg/mL) of L5 or L1 (the least electronegative LDL subfraction). NRCMs were examined for apoptosis and viability, CaMKII activity, and the expression of phosphorylated CaMKIIδ and NOX2/gp91 phox . The function of K ATP and action potentials (APs) was analyzed by using the patch-clamp technique. Results In NRCMs, L5 but not L1 significantly induced cell apoptosis and reduced cell viability. Furthermore, L5 decreased Kir6.2 expression by more than 50%. Patch-clamp analysis showed that L5 reduced the K ATP current (I KATP ) density induced by pinacidil, a K ATP opener. The partial recovery of the inward potassium current during pinacidil washout was susceptible to subsequent inhibition by the I KATP blocker glibenclamide. Suppression of I KATP by L5 significantly prolonged the AP duration. L5 also significantly increased the activity of CaMKII, the phosphorylation of CaMKIIδ, and the expression of NOX2/gp91 phox . L5-induced apoptosis was prevented by the addition of the CaMKII inhibitor KN93 and the reactive oxygen species scavenger Mn (III)TBAP. Conclusions L5 but not L1 induces CM damage through the activation of the CaMKII pathway and increases arrhythmogenicity in CMs by modulating the AP duration. These results help to explain the harmful effects of L5 in cardiovascular-related disease. | Atherogenic L5 LDL induces cardiomyocyte apoptosis and inhibits KATP channels through CaMKII activation | 10.1186/s12944-020-01368-7 |
2020-08-21 | Background The present study was designed to test the hypothesis that in the liver, excessive fat accumulation impairs cholesterol metabolism mainly by altering the low-density lipoprotein-receptor (LDL-R) pathway. Method Young male Wistar rats were fed standard (SD), high fat (HFD; 60% kcal) or Western (WD; 40% fat + 35% sucrose (17.5% fructose)) diets for 2 or 6 weeks. Results Weight gain (~ 40 g) was observed only following 6 weeks of the obesogenic diets ( P < 0.01). Compared to the 2-week treatment, obesogenic diets tripled fat pad weight (~ 20 vs 7 g) after 6 weeks. Hepatic triglyceride (TG) levels were greater in response to both the WD and HFD compared to the SD ( P < 0.01) at 2 and 6 weeks and their concentrations were greater ( P < 0.05) in WD than HFD at 2 weeks. Plasma total cholesterol levels were higher ( P < 0.05) in animals submitted to WD. After 2 and 6 weeks, liver expression of LDL-R, proprotein convertase subtilisin/kexin 9 (PCSKk9) and sterol regulatory element binding protein 2 (SREBP2), involved in LDL-cholesterol uptake, was lower in animals submitted to WD than in others treated with HFD or SD ( P < 0.01). Similarly, low-density lipoprotein-receptor-related protein 1 (LRP1) and acyl-CoA cholesterol acyltransferase-2 (ACAT-2) mRNA levels were lower ( P < 0.01) among WD compared to SD-fed rats. Expression of the gene coding the main regulator of endogenous cholesterol synthesis, 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMGCoAR) was reduced in response to WD compared to SD and HFD at 2 ( P < 0.001) and 6 ( P < 0.05) weeks. Being enriched in fructose, the WD strongly promoted the expression of carbohydrate-response element binding protein (ChREBP) and acetyl-CoA carboxylase (ACC), two key regulators of de novo lipogenesis. Conclusion These results show that the WD promptly increased TG levels in the liver by potentiating fat storage. This impaired the pathway of hepatic cholesterol uptake via the LDL-R axis, promoting a rapid increase in plasma total cholesterol levels. These results indicate that liver fat content is a factor involved in the regulation of plasma cholesterol. | Two weeks of western diet disrupts liver molecular markers of cholesterol metabolism in rats | 10.1186/s12944-020-01351-2 |
2020-08-20 | Background Primary implant stability is essential for osseointegration. To increase stability without changing the implant size, the thread length must be extended by reducing pitch, using a double-threaded implant, or reducing pitch/lead and lead angle to half that of a single-threaded implant. Materials and methods We tested the stabilities of these configurations using artificial bone. A 1.2-mm pitch, single-threaded implant (12S) was the control. We tested a 0.6-mm pitch/1.2-mm-lead double-threaded implant (06D) and a 0.6-mm pitch/lead single-threaded implant (06S). We compared stabilities by measuring insertion torque, removal torque, and the implant stability quotient (ISQ). Damage to bone tissue caused by the implants was evaluated using microscopy and morphometric analysis. Results We show that 06D and 06S significantly improved stability compared with the 12S reference. The stability of 06S was significantly greater compared with that of 06D, except for ISQ. The three implants were associated with bone tissue damage characterized by debris and voids surrounding the implant/bone interface. The 06D caused the most tissue damage, followed by 06S and then 12S. Conclusion These findings indicate that primary stability was significantly improved by changing the implant size, extending the thread length with reduced pitch/lead, and reducing the lead angle to half that of a single-threaded implant compared with a double-threaded implant. | Effects of implant thread design on primary stability—a comparison between single- and double-threaded implants in an artificial bone model | 10.1186/s40729-020-00239-1 |
2020-08-19 | Among metal-based additive manufacturing, wire and arc additive manufacturing is receiving increasing attention for the production of components with medium to large dimensions. In the current research, the production of low-carbon steel thin-walled components by wire and arc additive manufacturing was addressed. Firstly, the influence of two depositing direction strategies on the wall shape was investigated. Subsequently, the effect of heat input on the shape stability and the microstructure evolution of the walls was studied. The results indicated that the alternating depositing direction strategy was more suited to build thin walls with relatively regular height. The heat input significantly influenced the shape stability, but had slight effects on the microstructure evolution. The microstructure of the walls varied from the top to the bottom regions, leading to a variation in hardness from 157 ± 3.11 to 192 ± 4.30 (HV5). The microstructure of the built thin walls can be distinguished in three regions: The upper region exhibited lamellar structures; the middle region dominantly featured granular structures of ferrites with a small proportion of pearlites, which appear in the boundaries of grains; and the lower region showed a mix of lamellar and equiaxed structures of ferrites. The tensile properties of the built material also exhibited anisotropic characteristics: The yield strength and ultimate tensile strength vary from 320 ± 6 to 362 ± 8 MPa and from 429 ± 8 to 479 ± 7 MPa, respectively. | A study on wire and arc additive manufacturing of low-carbon steel components: process stability, microstructural and mechanical properties | 10.1007/s40430-020-02567-0 |
2020-08-17 | The proposed work concentrates on the integration of an 8-GHz voltage-controlled oscillator (VCO) and a frequency tripler for 24-GHz local oscillator generation. By stacking the VCO and the tripler with a current-reused topology, the power consumption of this integration can be saved. The proposed circuit with a total chip area of 0.7 mm ×0.8 mm is implemented in a 0.18 μm CMOS process. As the tuning voltage increases from 0 to 2 V, the measured frequency tuning range (FTR) of the VCO is from 7.06 to 8.33 GHz. The final resulting output frequency from the tripler ranges from 21.18 to 24.98 GHz (16.5% FTR). The core circuit totally consumes 5 mA from a 1.8-V supply voltage. The measured phase noises at the VCO and frequency tripler outputs are − 113.76 and − 105.1 dBc/Hz at 1-MHz offset frequency, respectively, when V tune is 0 V. The best evaluated figure of merit with tuning is − 187.2 dBc/Hz (decibels relative to carrier). Closed form equations allow for a performance driven design for both PLL and estimator. By using a variable sample frequency controlled by the PLL, the Kalman filter is always operated around its center frequency, which is the rated grid frequency. The new topology is compared to other published single-phase PLL designs and its operation is verified by both simulations and experiments. This integration of a VCO and a frequency tripler exhibits a high potential for the use in low-power 24-GHz phase-locked loops. The PLL designed using dual mode logic technique exhibits excellent performance even under severely distorted utility grid voltage conditions. This robustness makes it very suitable for use in systems connected to grids having an important share of non-linear loads. | Enhanced Digital Synthesized Phase Locked Loop with High Frequency Compensation and Clock Generation | 10.1007/s11220-020-00308-0 |
2020-08-14 | In this study the first viscosity measurements in the glass transition range of melts from highly explosive large-volume eruptions from the Colli Albani Volcanic District (CAVD) are presented. The magmas are ultrapotassic, rich in iron and CaO and characterised by a low silica content (< 45 wt%). Melt compositions range from tephri-phonolitic to foiditic. The Colli Albani eruptions appear anomalous since they produced a large volume of erupted material in spite of their silica undersaturated compositions. The viscosity of the Colli Albani melt changes as the melt composition evolves from the original melt to a country-rock contaminated melt to a crystal-bearing melt with a permanent decrease in liquid viscosity. Conventional estimations of viscosities assume these magmas to have a low viscosity. The presented data show that the melt viscosities are higher than expected. Taking into account further chemical or rheological features of a melt, the investigated CAVD melts are not that striking as assumed in comparison with other large-volume eruptions. Consequently, considering the alkaline-earth to alkaline ratio together with the SiO 2 content could provide an alternative when comparing large volume eruptions. | Rheology of melts from the colli albani volcanic district (Italy): a case study | 10.1007/s00410-020-01720-1 |
2020-08-10 | Background Low back-related leg pain (LBLP) is a challenge for healthcare providers to manage. Neuropathic pain (NP) is highly prevalent in presentations of LBLP and an accurate diagnosis of NP in LBLP is essential to ensure appropriate intervention. In the absence of a gold standard, the objective of this systematic review was to evaluate the diagnostic utility of patient history, clinical examination and screening tool data for identifying NP in LBLP. Methods This systematic review is reported in line with PRISMA and followed a pre-defined and published protocol. CINAHL, EMBASE, MEDLINE, Web of Science, Cochrane Library, AMED, Pedro and PubMed databases, key journals and the grey literature were searched from inception to 31 July 2019. Eligible studies included any study design reporting primary diagnostic data on the diagnostic utility of patient history, clinical examination or screening tool data to identify NP in LBLP, in an adult population. Two independent reviewers searched information sources, assessed risk of bias (QUADAS-2) and used GRADE to assess overall quality of evidence. Results From 762 studies, 11 studies were included. Nine studies out of the 11 were at risk of bias. Moderate level evidence supports a cluster of eight signs (age, duration of disease, paroxysmal pain, pain worse in leg than back, typical dermatomal distribution, worse on coughing/sneezing/straining, finger to floor distance and paresis) for diagnosing lumbosacral nerve root compression, demonstrating moderate/high sensitivity (72%) and specificity (80%) values. Moderate level evidence supports the use of the StEP tool for diagnosing lumbar radicular pain, demonstrating high sensitivity (92%) and specificity (97%) values. Conclusions Overall low-moderate level evidence supports the diagnostic utility of patient history, clinical examination and screening tool data to identify NP in LBLP. The weak evidence base is largely due to methodological flaws and indirectness regarding applicability of the included studies. The most promising diagnostic tools include a cluster of 8 patient history/clinical examination signs and the StEP tool. Low risk of bias and high level of evidence diagnostic utility studies are needed, in order for stronger recommendations to be made. | Diagnostic utility of patient history, clinical examination and screening tool data to identify neuropathic pain in low back related leg pain: a systematic review and narrative synthesis | 10.1186/s12891-020-03436-6 |
2020-08-09 | Industrial activities that consume water generate wastewater as a by-product of processing which introduces various contaminants such as heavy metals into the neighbouring water bodies that creates adverse effects on the surrounding environment. Tannery industry releases more toxic effluent than most industries, which directly and indirectly exerts stress on various ecosystems. The heavy metal chromium (Cr), one of the pollutants found in tannery effluent, is very much detrimental to human health, animals, and plants. Conventional physico-chemical and biological processes can remove this heavy metal in considerable amounts. Recently, various applications of advanced technologies such as membrane technology, electrocoagulation, ion exchange, and electrodialysis for tannery wastewater have been growing due to their relative advantages over other technologies in terms of sustainability. This paper represents the review of various available techniques as well as represents a case study of chromium removal from tannery effluent by a low-cost absorbent. | An overview of chromium removal techniques from tannery effluent | 10.1007/s13201-020-01286-0 |
2020-08-09 | The Neoproterozoic charnockite–granite association of Okpella intrudes metasedimentary and migmatite-gneiss complex rocks in the eastern Igarra Schist Belt, southwestern Nigeria. In order to unravel the complex processes involved in the formation and tectonic evolution of the Igarra Schist Belt during the Neoproterozoic, detailed field, petrographic and whole-rock geochemical study of the charnockite–granite association and metasedimentary rocks around Okpella was conducted. Published data on the metasedimentary rocks and Pan-African granitoids in different sectors of the belt were also compiled for detailed interpretations. The charnockites and granites of Okpella show primary magmatic mineralogy and geochemical characteristics. They are silicic (> 63 wt% SiO 2 ), metaluminous to peraluminous, high-K calc-alkaline, ferroan, post-collisional granitoids. The garnet-biotite schist, calc-silicate gneiss and quartzite in the area are low–medium grade metasedimentary rocks. The mineralogy and geochemistry of the charnockites suggest that the charnockitic melt was derived from mafic lower continental crust through partial melting and assimilation-fractionation processes. The granites probably originated from mixed melts derived from lower- to mid-crustal tonalites-trondhjemites-granodiorites and/or subducted metagreywackes and mantle-derived magmas (probably the charnockitic melt and/or its progenitor). The granites and charnockites are coeval and were presumably emplaced during the post-collisional stages of the Pan-African Orogeny. The garnet-biotite schist, calc-silicate gneiss and quartzite represent metamorphosed immature to slightly mature sedimentary rocks, probably greywacke, marl and subarkose, respectively, that were sourced from intermediate–acid rocks which underwent low–moderate chemical weathering with minor contribution from recycled sediment sources and deposited in active continental environments. The Neoproterozoic evolution of the Igarra Schist Belt, therefore, involved deposition and infolding of sediments in active continental margin during the early Pan-African followed by upwelling of basaltic magma from the mantle which underplated and crystallized in the lower continental crust and was subsequently partially melted to generate the charnockitic and granitic melts through mantle-crust interaction during the late Pan-African. | Petrography and geochemistry of Neoproterozoic charnockite–granite association and metasedimentary rocks around Okpella, southwestern Nigeria | 10.1007/s12517-020-05785-x |
2020-08-08 | We present a novel paleomagnetic record for the lower Matuyama chronozone, which includes the Réunion subchronozone and the lower Olduvai polarity reversal, from a continuous section of a 168-m-thick on-land marine succession in the southernmost part of the Boso Peninsula, central Japan. In this section, the Réunion subchronozone and the lower Olduvai reversal are observed at 38.6–44.6 m and 142.0 m, respectively. The average sedimentation rates between the lower and upper Réunion boundaries and between the upper Réunion boundary and lower Olduvai boundary are calculated as 25 cm/ky and 57 cm/ky, respectively. The virtual geomagnetic pole (VGP), observed in the Boso Peninsula, at both the upper and lower Réunion boundaries passed across the equator within a similar longitudinal band over Africa. Immediately below the upper boundary, between 43.0 and 43.5 m, the VGP settled in a cluster area around China. Relative paleointensity (RPI) values for the entire Réunion interval are generally lower than the average for the entire interval from the Réunion to the lower Olduvai subchronozone. Conversely, the VGP for the lower Olduvai reversal boundary did not pass across the equator within a narrow longitudinal band but settled in several cluster areas; i.e., the southern Indian Ocean, North America, and the southern South Pacific Ocean off South America. The VGP then moved rapidly between the clusters. The locations of VGP cluster areas in the lower Olduvai reversal seem to coincide with areas where a vertical component of the present geomagnetic non-axial dipole (NAD) field is dominant. During the reversal, the RPI declined rapidly and recovered slowly as the VGP moved rapidly between cluster areas. Our new paleomagnetic data are one of the most detailed records for those geomagnetic reversals from marine sediments, and will, therefore, help to understand the dynamics of the geomagnetic reversals. | A paleomagnetic record of the early Matuyama chron including the Réunion subchron and the onset Olduvai boundary: High-resolution magnetostratigraphy and insights from transitional geomagnetic fields | 10.1186/s40645-020-00352-0 |
2020-08-08 | Abstract The Chiba composite section (CbCS), in the middle of the Boso Peninsula in central Japan, was ratified as the Global Boundary Stratotype Section and Point (GSSP) for the Lower–Middle Pleistocene boundary, accompanied by the Matuyama–Brunhes (M–B) paleomagnetic polarity boundary in January 2020. This study examined the calcareous nannofossil biostratigraphy of the CbCS to describe potential nannofossil events and discuss sea-surface environments around the M–B paleomagnetic polarity boundary. There are no clear biohorizons at the M–B paleomagnetic polarity boundary, although a temporary disappearance of Gephyrocapsa specimens (≥ 5 μm in diameter), an important calcareous nannofossil genus in the Pleistocene, occurs just above the Lower–Middle Pleistocene boundary. Although this is a characteristic event around the M–B paleomagnetic polarity boundary, it is unclear whether the event is globally traceable. Changes in the environmental proxy taxa of calcareous nannofossils in the CbCS revealed that sea-surface environments were driven by glacial-interglacial and millennial-scale climate forces. The time-transgressive change of the Tn value, a calcareous nannofossil temperature index, is mostly concordant with the planktonic foraminiferal oxygen isotope fluctuation. Abundant occurrences of a warm-water species, Umbilicosphaera spp., indicate that the Kuroshio Current was strong after ~ 783 ka. Even the strong influence of the Kuroshio Current, cooling events related to southward movements of the Kuroshio Front occurred every 10,000 years based on the presence of a cold-water taxon, Coccolithus pelagicus . Additionally, the inflow of coastal waters strengthened after ~ 778 ka because of abundant occurrences of Helicosphaera spp. Millennial-scale sea-surface changes were also inferred from detected floral fluctuations of less than 10,000 years. Graphical abstract | Calcareous nannofossil biostratigraphy of the Lower–Middle Pleistocene boundary of the GSSP, Chiba composite section in the Kokumoto Formation, Kazusa Group, central Japan, and implications for sea-surface environmental changes | 10.1186/s40645-020-00355-x |
2020-08-08 | Benign prostate hyperplasia (BPH) is a common disease in old-age males, accounting for approximately 77% of morbidity within the age range of 40 to 70 years. It has been shown that morbidity increases with social graying. Quisqualis indica linn (QI) has been used to treat inflammation, stomach pain, and digestion problems. In this study, we evaluated the symptom-regulating effects of QI extract on a testosterone-induced BPH rat model. After inducing BPH in rats using testosterone propionate (TP) injection, we assessed basal intraurethral pressure (IUP) and increments of IUP elicited by electrical field stimulation (5 V, 5, 10, or 20 Hz) or phenylephrine (Phe) (0.01, 0.03, 0.1 mg/kg IV). To induce BPH, 8-week-old rats were subjected to a daily subcutaneous TP (3 mg/kg) injection for 4 weeks. Finasteride (Fina) (10 mg/kg PO) was administered to the rats in the first treatment, while QI (150 mg/kg PO) was administered to those in the second group. Blood pressure was measured together with IUP, after which low urinary tract (LUT), ventral prostate (VP), testicle, and corpus spongiosum were isolated and weighed. Basal IUPs for the Fina- and QI-treated groups were 87.6 and 86.8%, respectively. LUT and VP organ weights in the QI group were lower than those in the Fina group. However, the QI group showed significantly reduced electrical stimulated or Phe-induced IUP increment compared to the Fina and BPH groups. These results proved that QI can be beneficial for BPH symptoms by inhibiting 5α-reductase and consequently decreasing prostate and releasing urinary pressure. | Quisqualis indica extract ameliorates low urinary tract symptoms in testosterone propionate-induced benign prostatic hyperplasia rats | 10.1186/s42826-020-00059-9 |
2020-08-07 | Background Numerous data obtained by different research laboratories indicate that specific IgE production is triggered independently of specific IgG or IgA ones and so it is not linked to fully matured germinal centers formation in the secondary lymphoid organs. The aim of this study was to clarify whether specific IgE production is triggered by low antigen doses administrated in tertiary tissues enriched by lymphoid structures. Methods Ovalbumin (OVA) in different doses (100 ng to 10 μg) was administrated three times a week for 4–5 weeks intraperitoneally (i.p.) or subcutaneously (s.c.) to female BALB/c mice in the wither region which is enriched in fat-associated lymphoid clusters or in the foot pad region not containing them. Results OVA-specific IgE was predominantly induced by low but not high antigen doses and only after immunization into the withers. IgE isotype switching was triggered exclusively in the withers adipose tissue but not in the regional lymph nodes while mature IgE expressing cells were observed both in the withers and lymph nodes. Anti-proliferative genotoxic stress inducing drugs shifted the balance from IgG1 towards IgE production. Conclusions Tertiary lymphoid structures possess unique environment where B-cell antibody isotype switching to IgE predominantly occurs. This phenomenon is partially explained by hampered proliferation of B-cells in these structures. | Tertiary lymphoid structure related B-cell IgE isotype switching and secondary lymphoid organ linked IgE production in mouse allergy model | 10.1186/s12865-020-00376-7 |
2020-08-05 | Ambient temperature has substantial impacts on vehicle emissions, but the impacts may differ between traditional and alcohol gasolines. The objective of this study was to investigate the effects of temperature on gaseous and particulate emissions with both traditional and alcohol gasoline. Regulated gaseous, particle mass (PM), particle number (PN) and black carbon (BC) emissions from typical passenger vehicles were separately quantified with gasoline, E10 (10% ethanol and 90% gasoline by volume) and M15 (15% methanol and 85% gasoline by volume) at both 30°C and −7°C. The particulate emissions with all fuels increased significantly with decreased temperature. The PM emissions with E10 were only 48.0%–50.7% of those with gasoline at 30°C but increased to 59.2%–79.4% at −7°C. The PM emissions with M15 were comparable to those with gasoline at 30°C, but at −7°C, the average PM emissions were higher than those with gasoline. The variation trend of PN emissions was similar to that of PM emissions with changes in the fuel and temperature. At 30°C, the BC emissions were lower with E10 and M15 than with gasoline in most cases, but E10 and M15 might emit more BC than gasoline at −7°C, especially M15. The results of the transient PN and BC emission rates show that particulate emissions were dominated mainly by those emitted during the cold-start moment. Overall, the particulate emissions with E10 and M15 were more easily affected by ambient temperature, and the advantages of E10 and M15 in controlling particulate emissions declined as the ambient temperature decreased. | Effects of ambient temperature on regulated gaseous and particulate emissions from gasoline-, E10- and M15-fueled vehicles | 10.1007/s11783-020-1306-1 |
2020-08-03 | Background Extracorporeal cardiopulmonary resuscitation (ECPR) with extracorporeal membrane oxygenation (ECMO) is a promising therapy for out-of-hospital cardiac arrest (OHCA) compared with conventional cardiopulmonary resuscitation (CCPR). The no and low-flow time (NLT), the interval from collapse to reperfusion to starting ECMO or to the return of spontaneous circulation (ROSC) in CCPR, is associated with the neurological outcome of OHCA. Because the effects of target temperature management (TTM) on the outcomes of ECPR are unclear, we compared the neurological outcomes of OHCA between ECPR and CCPR without TTM. Methods We performed retrospective subanalyses of the Japanese Association for Acute Medicine OHCA registry. Witnessed cases of adult cardiogenic OHCA without TTM were selected. We performed univariate, multivariable and propensity score analyses to compare the neurological outcomes after ECPR or CCPR in all eligible patients and in patients with NLT of > 30 min or > 45 min. Results We analysed 2585 cases. Propensity score analysis showed negative result in all patients (odds ratio 0.328 [95% confidence interval 0.141–0.761], P = 0.010). However, significant associated with better neurological outcome was shown in patients with NLT of > 30 min or > 45 min (odds ratio 2.977 [95% confidence interval 1.056–8.388], P = 0.039, odds ratio 5.099 [95% confidence interval 1.259–20.657], P = 0.023, respectively). Conclusion This study revealed significant differences in the neurological outcomes between ECPR and CCPR without TTM, in patients with NLT of > 30 min. | Extracorporeal cardiopulmonary resuscitation without target temperature management for out-of-hospital cardiac arrest patients prolongs the therapeutic time window: a retrospective analysis of a nationwide multicentre observational study in Japan | 10.1186/s40560-020-00478-9 |
2020-08-03 | Background Dietary protein deficiency and amino acid imbalance cause hepatic fat accumulation. We previously demonstrated that only arginine deficiency or total amino acid deficiency in a diet caused significant hepatic triglyceride (TG) accumulation in young Wistar rats. In this study, we explored the mechanisms of fatty liver formation in these models. Methods We fed 6-week-old male Wistar rats a control diet (containing an amino acid mixture equivalent to 15% protein), a low-total-amino acid diet (equivalent to 5% protein; 5PAA), and a low-arginine diet (only the arginine content is as low as that of the 5PAA diet) for 2 weeks. Results Much greater hepatic TG accumulation was observed in the low-arginine group than in the low-total-amino acid group. The lipid consumption rate and fatty acid uptake in the liver did not significantly differ between the groups. In contrast, the low-total-amino acid diet potentiated insulin sensitivity and related signaling in the liver and enhanced de novo lipogenesis. The low-arginine diet also inhibited hepatic very-low-density lipoprotein secretion without affecting hepatic insulin signaling and lipogenesis. Conclusions Although the arginine content of the low-arginine diet was as low as that of the low-total-amino acid diet, the two diets caused fatty liver via completely different mechanisms. Enhanced lipogenesis was the primary cause of a low-protein diet-induced fatty liver, whereas lower very-low-density lipoprotein secretion caused low-arginine diet-induced fatty liver. | Low-arginine and low-protein diets induce hepatic lipid accumulation through different mechanisms in growing rats | 10.1186/s12986-020-00477-5 |
2020-08-03 | Background Circulating cell-free DNA (cfDNA) methylation has been demonstrated to be a promising approach for non-invasive cancer diagnosis. However, the high cost of whole genome bisulfite sequencing (WGBS) hinders the clinical implementation of a methylation-based cfDNA early detection biomarker. We proposed a novel strategy in low-pass WGBS (~ 5 million reads) to detect methylation changes in circulating cell-free DNA (cfDNA) from patients with liver diseases and hepatocellular carcinoma (HCC). Methods The effective small sequencing depth were determined by 5 pilot cfDNA samples with relative high-depth WGBS. CfDNA of 51 patients with hepatitis, cirrhosis, and HCC were conducted using low-pass WGBS. The strategy was validated in an independent WGBS cohort of 32 healthy individuals and 26 early-stage HCC patients. Fifteen paired tumor tissue and buffy coat samples were used to characterize the methylation of hepatitis B virus (HBV) integration regions and genome distribution of cfDNA. Results A significant enrichment of cfDNA in intergenic and repeat regions, especially in previously reported HBV integration sites were observed, as a feature of cfDNA and the bias of cfDNA release. Methylation profiles nearby HBV integration sites were a better indicator for hypomethylation of tumor genome comparing to Alu and LINE (long interspersed nuclear element) repeats, and were able to facilitate the cfDNA-based HCC prediction. Hypomethylation nearby HBV integration sites (5 kb flanking) was detected in HCC patients, but not in patients with hepatitis and cirrhosis (Methyl HBV5k , median:0.61 vs 0.72, P = 0.0003). Methylation levels of integration sites certain candidate regions exhibited an area under the receiver operation curve (AUC) value > 0.85 to discriminate HCC from non-HCC samples. The validation cohort achieved the prediction performance with an AUC of 0.954. Conclusions Hypomethylation around viral integration sites aids low-pass cfDNA WGBS to serve as a non-invasive approach for early HCC detection, and inspire future efforts on tumor surveillance for oncovirus with integration activity. | Hypomethylation in HBV integration regions aids non-invasive surveillance to hepatocellular carcinoma by low-pass genome-wide bisulfite sequencing | 10.1186/s12916-020-01667-x |
2020-08-03 | Background Differentiating Ventilator-Associated Tracheobronchitis (VAT) from Ventilator-Associated Pneumonia (VAP) may be challenging for clinicians, yet their management currently differs. In this study, we evaluated the accuracy of the Clinical Pulmonary Infection Score (CPIS) to differentiate VAT and VAP. Methods We performed a retrospective analysis based on the data from 2 independent prospective cohorts. Patients of the TAVeM database with a diagnosis of VAT ( n = 320) or VAP ( n = 369) were included in the derivation cohort. Patients admitted to the Intensive Care Centre of Lille University Hospital between January 1, 2016 and December 31, 2017 who had a diagnosis of VAT ( n = 70) or VAP ( n = 139) were included in the validation cohort. The accuracy of the CPIS to differentiate VAT from VAP was assessed within the 2 cohorts by calculating sensitivity and specificity values, establishing the ROC curves and choosing the best threshold according to the Youden index. Results The areas under ROC curves of CPIS to differentiate VAT from VAP were calculated at 0.76 (95% CI [0.72–0.79]) in the derivation cohort and 0.67 (95% CI [0.6–0.75]) in the validation cohort. A CPIS value ≥ 7 was associated with the highest Youden index in both cohorts. With this cut-off, sensitivity and specificity were respectively found at 0.51 and 0.88 in the derivation cohort, and at 0.45 and 0.89 in the validation cohort. Conclusions A CPIS value ≥ 7 reproducibly allowed to differentiate VAT from VAP with high specificity and PPV and moderate sensitivity and NPV in our derivation and validation cohorts. | Accuracy of the clinical pulmonary infection score to differentiate ventilator-associated tracheobronchitis from ventilator-associated pneumonia | 10.1186/s13613-020-00721-4 |
2020-08-01 | LiFePO 4 (LFP) has been recommended as a promising cathode material due to its excellent cycle performance and high safety. However, the poor performance of low temperatures restricts the development and application of LFP cathode. Herein, the electrochemical properties of the previously synthesized LFP/C-P composite with carbon coating and phosphorus doping are discussed in the low temperature. In the low-temperature environment of − 40 °C, the first discharge-specific capacity of the LFP/C-P composite cathode at 0.1 C can reach 82.7 mAh g −1 , while discharge-specific capacity of pristine commercial LFP is only 72.2 mAh g −1 . To further improve the electrochemical performance of LFP/C-P at low temperatures, different charging-discharging methods were compared. It is noted that prolonging the constant voltage charging time can further improve the electrochemical performance of the cell, which increases the discharge capacity of LFP/C-P to 85.8 mAh g −1 . The LFP/C-P composite cathode therefore not only ameliorates the poor electrochemical performance of LFP but provides a new way to broaden its application range. | Investigation on electrochemical performance at the low temperature of LFP/C-P composite based on phosphorus doping carbon network | 10.1007/s11581-020-03567-9 |
2020-08-01 | In this study, low-temperature fired CaMg 1− x Li 2 x Si 2 O 6 microwave dielectric ceramics were prepared via the traditional solid-state reaction method. In this process, 0.4 wt% Li 2 CO 3 -B 2 O 3 -SiO 2 -CaCO 3 -Al 2 O 3 (LBSCA) glass was added as a sintering aid. The results showed that ceramics consisted of CaMgSi 2 O 6 as the main phase. The second phases were CaSiO 3 always existing and Li 2 SiO 3 occurring at substitution content x > 0.05. Li + substitution effectively lowered sintering temperature due to 0.4 wt% LBSCA and contributed to grain densification, and the most homogeneous morphology could be observed at x = 0.05. The effects of relative density, the second phase, and ionic polarizability on dielectric constant (ε r ) were investigated. The quality factor ( Q × f ) varied with packing fraction that concerned the second phase. Moreover, the temperature coefficient of the resonant frequency (τ f ) was influenced by MgO 6 octahedral distortion and bond valence. Excellent dielectric properties of the CaMg 1− x Li 2 x Si 2 O 6 ceramic was exhibited at x = 0.05 with ε r = 7.44, Q × f = 41,017 GHz ( f = 15.1638 GHz), and τ f = −59.3 ppm/°C when sintered at 900 °C. It had a good application prospect in the field of low-temperature co-fired ceramic (LTCC) substrate and devices. | Low-temperature sintering and microwave dielectric properties of CaMg1−xLi2xSi2O6 (x = 0−0.3) ceramics | 10.1007/s40145-020-0390-9 |
2020-08-01 | For two commonly used modified emulsified asphalts, styrene butadiene rubber (SBR) and styrene butadiene styrene (SBS), direct heating and low-temperature evaporation methods were respectively applied to obtain the asphaltic residues. Nanotechnology provides a great solution to road construction issues. However, the use of nanoparticles increases the durability of asphalts and enhances the performance of bitumen. Dynamic shear rheometer (DSR) was employed for temperature scanning test and multiple stress creep recovery (MSCR) test of the asphaltic residues. In this paper, the changes in the rheological properties of the asphaltic residues were compared and analyzed. The influence of evaporation temperature on the rheological properties of modified emulsified asphaltic residues obtained by evaporation was discussed. Evaporation tests showed that the higher the evaporation temperature, the larger the mass reduction of residues at the early stage and the shorter the time needed to reach stabilization. The solid contents of modified emulsified asphaltic residues obtained under different evaporation temperatures also differed. The solid content of asphaltic residues obtained under the evaporation temperature of 60 °C was closest to that by the low-temperature evaporation method. This indicated influence of the evaporation temperature on the solid content of asphaltic residues. Based on the results of temperature scanning test and MSCR test, there was a significant difference in the rheological properties of the asphaltic residues obtained by direct heating and low-temperature evaporation methods. The anti-deformation capacity under high temperature in asphaltic residues obtained at different evaporation temperatures varied more greatly. For SBS-modified emulsified asphalt, the rutting resistance under high temperature in residues obtained by the low-temperature evaporation method was better; however, the opposite was true for the SBR-modified emulsified asphalt. This indicated that the high-temperature evaporation method may overestimate the high-temperature properties of SBR-modified emulsified asphaltic residues and underestimate the high-temperature properties of SBS-modified emulsified asphaltic residues. For the emulsified asphalt samples, the appropriate method to obtain asphaltic residues that are closest to the actual road conditions should be optimized depending on the specific purposes. | RETRACTED ARTICLE: Influence of evaporation temperature on the rheological properties of modified emulsified asphaltic residues | 10.1007/s11051-020-04952-1 |
2020-08-01 | In our work, we have developed a low-temperature and pressure-promoted solid-phase method for synthesizing electrode materials, which can realize surface functionalization and the adjustment of pore structure. In the closed autoclave at 200 °C, and oxygen-modified carbon materials can be finally obtained by simply mixing oxalic acid with activated carbon materials. The specific surface area of the prepared electrode material is increased from the initial 1604 to 1814 m 2 g −1 ; the specific capacitance is increased from the initial 100 to 187 F g −1 . The cycle stability test is carried out at a current density of 4 A g −1 , which still has an initial capacitance of 73% after 5000 cycles. In the EMIMBF 4 /AN electrolyte, the energy density is as high as 36.0 Wh kg −1 at a power density of 500.0 W kg −1 . | Low-temperature and pressure-promoted synthesis of porous carbon modified with oxygen for supercapacitor application | 10.1007/s11581-020-03539-z |
2020-08-01 | In this paper, austenitic EN-1.4404—AISI 316L stainless steel assemblies have been brazed using concentrated solar energy, in vacuum, air and argon media, under different heating and cooling conditions. A nickel-based alloy (EN 2.4360—Monel 400) has been used as a filler material for brazing, aiming to obtain mechanically and chemically resistant joints, with potential application in low Earth orbit assembling where the solar energy flux bears higher values and degradative conditions are more demanding. By brazing with Monel in vacuum, good quality joints were obtained with minimal defects, being composed of solid solution grains, with shear strength values of 285–320 MPa and elongation values of 4.5–6 mm, while in argon medium, shear strength values of 350–370 MPa and elongation values of 7–8 mm have been obtained. Concentrated solar energy brazing in vacuum and argon has led to promising results which could prove an alternative to on-site low Earth orbit construction joining. | The influence of concentrated solar energy flux on the structure and properties of stainless steel brazed joints | 10.1007/s10973-019-09113-8 |
2020-08-01 | The deployment of thermally activated building systems (TABS) in buildings has increased to reduce energy consumption and peak loads whilst improving indoor comfort. Previous studies provided important references for the design and operation of TABS in several buildings and various climates. However, guidelines for the use of TABS design and operation in China’s buildings and climates, where TABS-related parameters can be analysed and optimised under various weather conditions, are still insufficient. Firstly, this study investigated the relationship between the design (e.g. pipe spacing S and wall area A) and operation parameters (e.g. the flow rate v and water inlet temperature T inlet ) and the heat flux using a mathematical model of a thermally activated wall (TAW) system. Results indicated that the water inlet temperature T inlet and the indoor temperature T in significantly affected the heat transfer rate of the TAW system. Secondly, a TAW system testbed was set up to conduct experiments for the validation of the simulation model developed in COMSOL. Lastly, a TAW design chart was presented to provide climate-based guidelines for TAW applications in buildings located in the cold regions, which could be expanded to other climates in China. | Optimal design and operation of thermally activated wall in the ultra-low energy buildings in China | 10.1007/s12273-020-0620-7 |
2020-08-01 | Different heating treatments with the variation of heating rates, holding temperatures and holding time were used to simulate the LTPS procedure. The experimental results show that the reheating shrinkage rates of glass substrates are rarely changed with increasing the heating rate, but strongly enhanced by raising the holding temperature and time, which shows that the reheating shrinkage of glass is closely related to heat treatment and structural relaxation. The production process of glass is critical to the reheating shrinkage of glass. | Influencing Factors of Reheating Shrinkage Rate of Glass Substrate on LTPS Process | 10.1007/s11595-020-2307-4 |
2020-08-01 | Three Mn–Ce–O x /TiO 2 mixed oxides (MCT) were prepared by sol–gel (SG), citric acid complexing (CA), and co-precipitation (CP) methods and used as catalysts for selective catalytic reduction of NO with NH 3 (NH 3 -SCR) at low temperatures (75–200 °C). The physicochemical properties of the prepared catalysts were investigated by N 2 adsorption, X-ray diffraction (XRD), temperature-programmed reduction by H 2 (H 2 -TPR), adsorption of NH 3 and NO followed by temperature-programmed desorption (NH 3 /NO-TPD), X-ray photoelectron spectroscopy (XPS), and in situ diffuse-reflectance infrared Fourier transform (DRIFT) spectroscopy. The results show that both the low-temperature de-NO x activity and the resistance to SO 2 poisoning of the Mn–Ce–O x /TiO 2 catalyst decrease in the order of MCT-CP > MCT-SG > MCT-CA. These disparities can be mainly attributed to the difference in specific surface area, fractions of Mn 4+ (Mn 4+ /(Mn 2+ +Mn 3+ +Mn 4+ )) and surface adsorbed oxygen (surface adsorbed oxygen/(surface adsorbed oxygen + lattice oxygen)) species, and the adsorption capacity for NH 3 and NO of the different catalysts. The effect of preparation methods (sol–gel, citric acid complexing, and co-precipitation) on the performance of Mn–Ce–O x /TiO 2 catalyst was investigated. The catalyst prepared by co-precipitation exhibits higher low-temperature activity and better SO 2 resistance than the counterparts prepared by the other two methods. Mn–Ce–O x /TiO 2 catalysts were prepared by sol–gel, citric acid complexing, and co-precipitation. The catalyst prepared by co-precipitation exhibits the highest activity for NH 3 -SCR of NO. The catalyst prepared by co-precipitation exhibits the best tolerance to SO 2 poisoning. | Low-temperature selective catalytic reduction of NO with NH3 over Mn–Ce–Ox/TiO2: a comparison between catalyst preparation methods | 10.1007/s10971-020-05268-1 |
2020-08-01 | Abstract Nanostructures with different mutual arrangement of phosphorus and titanium oxide groups were synthesized on the surface of low-density polyethylene (LDPE) films using the molecular layering technology by treatment in a different predetermined sequence with TiCl 4 , POCl 3 and H 2 O vapors. Based on the data of atomic force microscopy, differential thermal analysis, as well as the assessment of the energy characteristics of the surface by the value of the contact angle, it is shown that the sequence of formation of elemental oxide structures has a significant effect both on the chemical composition of surface nanostructures and on the surface morphology and thermal oxidation resistance of polyethylene. Depending on the sequence of introduction of additives, their concentration and ratio in grafted nanostructures change, surface energy increases by 30–50%, and the amounts of polar and dispersion components in its composition largely depend on the moisture content of the environment. It has been found that chemical modification with elemental oxide groups results in a smoothing of the matrix surface, and local destruction of the polymer is observed during the synthesis of two-component nanostructures. The presence of modifiers leads to an increase in the thermal-oxidative resistance of the composition by 50–110°, depending on its structure and composition, in comparison with the original LDPE. Therewith titanium is the most active inhibitor of polymer oxidation. | Influence of Structure of Chemically Grafted onto Polyethylene Surface Two-Component Titanium-Phosphoroxide Nanostructures on the Properties of Composite Material | 10.1134/S1070427220080121 |
2020-08-01 | The composition of intermetallic compounds and mechanical properties during friction stir welding of 2024 aluminum and AZ31B magnesium alloys was investigated by using offset tool at low heat input. The macrostructure of the Mg/Al joints was investigated by optical microscope, and microstructure characteristics were analyzed by scanning electron microscopy, energy-dispersive spectroscopy, and X-ray diffraction. The fracture section was also observed. It is found that the mechanical strength of the joint slowly decreases as the value of tool offset increases first and then decreases at the Al-side. The result showed that the joints have the best mechanical properties when offset 0.5 mm and the amount of IMCs is low. And it is found that only IMCs Al12Mg17 is found in the joints. Since Al 3 Mg 2 and Al 12 Mg 17 have eutectic temperatures of 450 °C and 437 °C, respectively, the offset caused the temperature to decrease during the FSW process, allowing Al 12 Mg 17 , with a lower eutectic temperature, to form easily. | Influence of tool offset on microstructure and properties of Mg/Al dissimilar alloys by friction stir welding joints at low heat input | 10.1007/s00170-020-05788-8 |
2020-08-01 | The goal of the study was to investigate if aviation emissions could influence the climate and weather by modifying the chemical composition of the atmosphere and subsequently, the radiative balance. To carry out the set objective, we used the global environmental multiscale atmospheric chemistry model with comprehensive tropospheric and stratospheric chemistry that is interactive with the radiation calculations. The model was run for two current climate scenarios, with and without aviation emissions. The results of the study indicate that the most significant difference in the jet stream propagation occurred during the winter season, and the smallest was observed during summer. Changes in the jet stream propagation vary by season and region. During the colder time of the year, the eddy-driven jet stream tends to shift poleward, while during the spring season the equatorward shift was observed in a scenario with aviation emissions. Analysis of regional changes shows that the most noticeable differences occurred over the Pacific Ocean, Atlantic Ocean and Asia. The changes over the oceans changed the occurrence of the North Pacific and Bermuda–Azores Highs. Over Asia (Siberia), a stronger and more poleward drift of the eddy-driven jet stream was observed in a scenario without aviation emission. Dissimilarity in the jet stream velocity was found only during the winter seasons when in a scenario with aviation emission, the jet stream velocity was 10 m/s smaller as compared to the scenario without aviation emission. | A note on the potential impact of aviation emissions on jet stream propagation over the northern hemisphere | 10.1007/s11600-020-00444-x |
2020-08-01 | A low-angle–dependent photonic crystal hydrogel (LAD-PCH) material was developed to simultaneously detect and remove uranyl ions (UO 2 2+ ). Different from traditional SiO 2 photonic crystal hydrogel with the problem of angle dependency, the LAD-PCH material overcomes the restriction of observation direction. The LAD-PCH is a composite material with the photonic crystal array of 180-nm monodisperse CdS@SiO 2 particles embedded into the functional hydrogel. As one UO 2 2+ can bind to multiple carboxyl groups and amide groups, the functional hydrogel fabricated by acrylic acid and acrylamide will shrink after chelating. These changes in the hydrogel volume alter the array spacing and trigger a blue shift of diffraction wavelength and naked-eye visual color changes of LAD-PCH. The color can vary from orange-red to orange, yellow, green, and cyan, corresponding to the determination range of 100 pM–100 μM. The LAD-PCH material detects UO 2 2+ sensitively as the lowest detectable concentration is about 100 pM, and removes UO 2 2+ high-efficiently as the maximum adsorption capacity of U(VI) is about 1010 mg g −1 at 298 K. This LAD-PCH material is convenient and has potential to simultaneously monitor and remove UO 2 2+ from uranium-polluted water. Schematic representation of the low-angle–dependent photonic crystal hydrogel (LAD-PCH) material for UO 2 2+ detection and removal: The structural colors of LAD-PCH material overcome the restriction of observation angles. After the ligands complex with UO 2 2+ , the networks of LAD-PCH show different degrees of shrinkage; these volume changes of hydrogel trigger obvious naked-eye visual color changes of LAD-PCH. | Low-angle–dependent CdS@SiO2 photonic crystal hydrogel material for visual detection and removal of uranyl ions | 10.1007/s00604-020-04456-8 |
2020-08-01 | The review concerns modification of polyether ether ketone (PEEK) using low-temperature plasma and ion implantation and presents the results of studies on the surface properties of modified PEEK samples obtained by wetting angle measurements, X-ray photoelectron spectroscopy, Fourier-IR-spectroscopy, scanning electron microscopy, and atomic force microscopy. This made it possible to investigate changes in the hydrophilicity, chemical structure, and morphology of the modified PEEK surface. The thermal and mechanical properties of the plasma-treated polymer are analyzed. Examples of biomedical applications of the modified PEEK are given. | Modification of polyether ether ketone by low-temperature plasma and ion implantation method for use in medicine and biology | 10.1007/s11172-020-2917-1 |
2020-08-01 | In order to increase flour recovery, resistant starch content and to lower the glycemic index and glycemic load, the water chestnuts were subjected to pre-optimized conditions of pre-conditioning. The low glycemic index water chestnut flour (F1) obtained thereafter was analyzed for different functional, viscous, thermal and structural properties. F1 exhibited improved functional properties due to gelatinization of starch followed by retrogradation during pre-conditioning which confirms its feasibility for development of diverse food products in comparison to commercially available market flour (F2). Pasting properties—peak viscosity, hold viscosity, breakdown viscosity, final viscosity and set back viscosity (SBV) were found significantly ( p < 0.01) higher in case of F1 than F2. Higher peak viscosity of F1 can be accorded to its higher swelling capacity than F2. Further, higher SBV of F1 suggests its susceptibility towards retrogradation and gel formation. Differential scanning calorimetry results revealed that gelatinization temperature, endothermic peak width, onset, peak and conclusion temperatures were significantly ( p < 0.01) lower, whereas enthalpy of gelatinization and peak height index were significantly ( p < 0.01) higher in case of F1 as compared to F2. Lower gelatinization transition temperatures of F1 could be attributed to its more water absorption ability than F2 which suggests its potential as a thickening agent in foods. ATR-FTIR studies revealed high absorbance ratio at 1047/1022 cm −1 in F1 as compared to F2 which confirmed the presence of packed double helices within the starch crystalline regions in F1 sample. Scanning electron microscopy showed the smooth, plumper and fused granules in F1 whereas disintegrated granules were observed in F2. | Visco-thermal and structural characterization of water chestnut flour | 10.1007/s13197-020-04327-3 |
2020-08-01 | Reactions between a boninitic or basaltic magma and harzburgite at shallow mantle depths are thought to be closely related to the formation of podiform chromitites, but little experimental data is available on these reactions. In this study, a series of experiments were conducted at 1.5 GPa and 1 000–1 400 °C to investigate the interactions between boninitic magma and harzburgite in homogenous mixed systems with varied bulk concentrations of water (∼0.7 wt.%–10 wt.%) and Cr 2 O 3 (∼0.2 wt.%–4 wt.%). In the experimental charges, chromite grains can be observed coexisting with orthopyroxene, clinopyroxene±olivine, and quenched melt in the Cr-bearing systems. The bulk concentration of Cr 2 O 3 in the starting material has a slight effect on compositional changes in the chromites generated. However, the Cr# (Cr # =100×Cr/(Cr+Al)) and Mg # (Mg # =100×Mg/(Mg+Fe)) values for the chromites exhibit positive and negative correlations, respectively, with the bulk H 2 O concentrations. At 1 100 °C, chromite Cr # values range from ∼33–35 to ∼58–65, and chromite Mg # values range from ∼70–73 to ∼55–58 when bulk H 2 O contents in the starting material are increased from ∼0.7 wt.% to ∼10 wt.%. The experimentally produced chromites have compositions (as expressed by Cr # , Mg # , and NiO and MnO contents) similar to natural chromites from low-Cr # chromitite bodies. We suggest that the interactions between boninitic magmas with varied H 2 O contents and harzburgite in a shallow mantle wedge could be a possible mechanism that forms the low-Cr # chromitites found in ophiolites. We emphasize here that H 2 O may play an important role in the compositional evolutions of natural chromitites. | Experimental Constraints on Formation of Low-Cr# Chromitite: Effect of Variable H2O and Cr2O3 on Boninitic-Magma and Harzburgite Reactions | 10.1007/s12583-020-1291-0 |
2020-08-01 | Spaceflight-induced bone losses have been reliably reproduced in Hind-Limb-Unloading (HLU) rodent models. However, a considerable knowledge gap exists regarding the effects of low-dose radiation and microgravity together. Ten-week-old male C57BL/6J mice, randomly allocated to Control ( CONT ), Hind-Limb Unloading ( HLU ), and Hind-Limb Unloading plus Irradiation ( HLUIR ), were acclimatized at 28 °C, close to thermoneutral temperature, for 28 days prior to the 14-day HLU protocol. HLUIR mice received a 25 mGy dose of X-ray irradiation, simulating 14 days of exposure to the deep space radiation environment, on day 7 of the HLU protocol. Trabecular bone mass was similarly reduced in HLU and HLUIR mice when compared to CONT , with losses driven by osteoclastic bone resorption rather than changes to osteoblastic bone formation. Femoral cortical thickness was reduced only in the HLUIR mice (102 μm, 97.5–107) as compared to CONT (108.5 μm, 102.5–120.5). Bone surface area was also reduced only in the HLUIR group, with no difference between HLU and CONT . Cortical losses were driven by osteoclastic resorption on the posterior endosteal surface of the distal femoral diaphysis, with no increase in the numbers of dead osteocytes. In conclusion, we show that low-dose radiation exposure negatively influences bone physiology beyond that induced by microgravity alone. | Unloading-Induced Cortical Bone Loss is Exacerbated by Low-Dose Irradiation During a Simulated Deep Space Exploration Mission | 10.1007/s00223-020-00708-0 |
2020-08-01 | Clothianidin served as the model pollutant to investigate the performance and mechanism of pollutant removal by dielectric barrier discharge plasma (DBD) combined with the titanium dioxide-reduced graphene oxide (rGO-TiO 2 ) composite catalyst. In this study, different ratios of titanium dioxide-graphene catalysts were loaded onto honeycomb ceramic plates via the sol-gel method, and the modified catalytic ceramic plates were characterized by XRD, SEM, FTIR, DRS, and energy dispersive X-ray. The results suggested that the rGO-TiO 2 was well loaded on the surface of the honeycomb ceramic plates. According to the results of the characterization experiments and the degradation of the clothianidin solution with different proportions of the catalyst, 8 wt% rGO-TiO 2 was selected as the optimum ratio for degradation. Clothianidin degradation efficiency was significantly influenced by input power, clothianidin concentration, pH value, liquid conductivity, free radical quencher. Finally, six degradation products of clothianidin were identified by HPLC-MS, and the possible transformation pathways of clothianidin degradation were identified. Graphical abstract | Catalytic degradation of clothianidin with graphene/TiO2 using a dielectric barrier discharge (DBD) plasma system | 10.1007/s11356-020-09303-0 |
2020-08-01 | The phase equilibrium of the quaternary system Na + , K + , Mg 2+ //Cl − –H 2 O and the quinary system Na + , K + , Mg 2+ //Cl − , $${\text{NO}}_{3}^{ - }$$ NO 3 - –H 2 O were investigated at 258 K using the isothermal dissolution equilibrium method. The phase diagrams were obtained based on the measured data. Double salt KCl·MgCl 2 ·6H 2 O was found in the quaternary and the quinary systems at 258 K. In the quaternary system Na + , K + , Mg 2+ //Cl − –H 2 O, there are two invariant points, five univariant curves, and four crystallization fields. The quinary system saturated with NaCl·2H 2 O contains four invariant points, nine univariant curves, and six crystallization fields corresponding to KCl, NaNO 3 , KNO 3 , Mg(NO 3 ) 2 ·6H 2 O, KCl·MgCl 2 ·6H 2 O and MgCl 2 ·8H 2 O. Mg(NO 3 ) 2 ·6H 2 O and MgCl 2 ·8H 2 O that have higher concentrations and stronger salting-out effect on other salts. Therefore, low-temperature pretreatment can offer an alternative treatment of brines in accordance with the necessity for current brine treatment processes to reduce the presence of double salts and be crucial for purer products to be separated. | Solid–Liquid Phase Equilibria in the Quinary System Na+, K+, Mg2+//Cl−,
$${\text{NO}}_{3}^{ - }$$
NO
3
-
–H2O and Its Subsystems at 258 K | 10.1007/s10953-020-00978-0 |
2020-08-01 | A natural trans -polyisoprene (PSN)-based rubber that functions as a light-activated oxygen-scavenging film were developed and applied this material to the packaging of roasted peanuts to prevent loss of quality due to oxidative degradation. Results of the oxygen scavenging analysis indicated that films exhibited reasonable oxygen scavenging rates. Roasted peanuts were packaged with or without LDPE/PSN films, and they were stored for 90 days at 25 °C for oxidative analysis. The roasted peanuts packaged with LDPE/PSN films exhibited significantly lower ( P < 0.05) headspace oxygen content within the packages than that of controls containing pure LDPE films. The Hunter L , a , and b values for peanuts packaged with LAE/PSN films were significantly higher ( P < 0.05) than those of the control sample. After 90 days of storage, total peroxide, TBA values increased. Total peroxide values increased from 0 to 28.11 meqQ 2 /Kg in controls and 17.51 ± 0.11 and 15.28 ± 0.01 meqO 2 /Kg in peanuts packaged in 10 and 20% PSN LDPE films, respectively, and similar results were observed for TBA values. These results demonstrated that experimentally developed LDPE/PSN oxygen scavenging films inhibited oxygen-mediated deterioration of roasted peanuts. The LDPE/PSN 10 and 20% films may be useful as active food‐packaging material. | The effect of trans-polyisoprene/LDPE based active films on oxidative stability in roasted peanuts | 10.1007/s11694-020-00433-0 |
2020-08-01 | Accurate streamflow measurements are often challenging for extremely shallow rivers within complex bathymetries. In this study, a new version of the fluvial acoustic tomography (FAT) system operated by high-frequency 53-kHz underwater acoustic transducers was used to measure the discharge of a shallow mountainous river. The system was placed under a stringent site condition that was challenging for receiving pure underwater acoustic signals and hence, resulted in low-quality estimates of the river discharge. To overcome this challenge, the shortest path graph method was adopted to capture the desired hydroacoustic data, which can improve the discharge measurements significantly. The results showed that the discharge estimated by the FAT was in very good agreement with that estimated by the rating curve method, suggesting that the FAT was capable of measuring the river discharge for shallow streams when the minimum water depth for a given cross-section was greater than 28 cm. In addition, the findings of this study indicated that under the low-flow condition, the temperature variations during the daytime and nighttime along the acoustic cross-section can play an important role in reducing the signal-to-noise ratio, hence leading to sparse and weak signals of the arrival time, as recorded by the acoustic transducers. | Measuring Low Flowrates of a Shallow Mountainous River Within Restricted Site Conditions and the Characteristics of Acoustic Arrival Times Within Low Flows | 10.1007/s11269-020-02557-w |
2020-08-01 | In the northwest of the Himalayan-Tibetan Orogen, the ∼250 km-long Kongur Shan extensional system in the eastern Pamir was formed during the convergence between the Indian and Asian plates. Tectonic activity of the Kongur Shan normal fault and the Tashkurgan normal fault can help to reveal the origin of east-west extension along the Kongur Shan extensional system. The Kongur Shan fault has been extensively studied, while the Tashkurgan fault calls for systemic research. In this study, low-temperature thermochronology including apatite fission track analysis and apatite and zircon (U-Th)/He analyses is applied to constrain the timing of activity of the Tashkurgan fault. Results indicate that the Tashkurgan fault initiated at 10−5 Ma, and most likely at 6−5 Ma. The footwall of the Tashkurgan fault has been exhumed at an average exhumation rate of 0.6−0.9 mm/a since the initiation of the Tashkurgan fault. Combined with previous research on the Kongur Shan fault, we believe that the origin of east-west extension along the Kongur Shan extensional system was driven by gravitational collapse of over-thickened Pamir crust. | Late Cenozoic Activity of the Tashkurgan Normal Fault and Implications for the Origin of the Kongur Shan Extensional System, Eastern Pamir | 10.1007/s12583-020-1282-1 |
2020-08-01 | Abstract Rheological, molecular, thermal, and mechanical properties of binary blends based on bimodal high-density polyethylene (HDPE; ethylene–1-hexene copolymer) and unimodal linear low-density polyethylene (LLDPE; ethylene–1-butene–1-hexene terpolymer) were studied. Six blends with different HDPE/LLDPE weight ratios, 80/20, 70/30, 60/40, 50/50, 40/60, and 20/80, were prepared by blending in a double-worm extruder. The correlation of the rheological properties of the blends, analyzed by the capillary and rotation methods, with the melt flow index and molecular characteristics was demonstrated. LLDPE with increased flowability (MFI = 3 g/10 min) as a polymer additive is an effective plasticizer allowing control of the melt viscosity in a wide range and choice of the optimum target value of the melt flow index of the blend. The activation energy of the melt flow was calculated, and the relationship between this quantity and the content of short-chain branchings in polyethylene blends was revealed. The blends obtained are homogeneous, but an increase in the content of LLDPE in HDPE leads to a change in the polyethylene structure, which is confirmed by a decrease in the crystallinity and in the lamella thickness. The strength values at the yield point and at break decrease with an increase in the fraction of LLDPE in HDPE. Changes in the properties of these blends in their processing into a film by flat-die extrusion were studied. | Structural, Rheological, and Mechanical Properties of Binary Compounds Based on High-Density Polyethylene and Linear Low-Density Polyethylene | 10.1134/S1070427220080108 |
2020-08-01 | Abstract Based on propargyl alcohol esters, new derivatives of phosphorous and phosphonic acids of the acetylene series of various structures were synthesized (10 compounds). The prepared substances (6 compounds) significantly inhibit the corrosion of 08kp low-carbon steel in 5 M HCl ( T = 20–60°C). The protective effect of these inhibitors increases with a rise in their content in solution and with increasing temperature. The strongest inhibition of steel corrosion is provided by phosphonic acid esters containing an alcohol group in their composition. For the synthesized corrosion inhibitors, an adsorption-polymerization mechanism of action is assumed, which is evidenced by the enhancement of the protective effect of these compounds with increasing temperature. | New Propargyl-Containing Derivatives of Phosphoric and Phosphonic Acids: Prospective Inhibitors of Acidic Corrosion of Steels for Oil Production | 10.1134/S1070427220080054 |
2020-08-01 | Low-rank coal reservoirs of Badaowan Formation and Xishanyao Formation are mainly developed in Junggar Basin. This paper discussed their features and coalbed methane (CBM) exploration potential based on geological survey, coal samples testing and mathematical fitting analysis. The pores are mainly small-micro- and large pores, and the porosity is 3.25–27.4% with an average of 9–10.51%; and macro-cracks and micro-fissures are well developed leading to a great variation of the permeability. The shallow coal reservoirs are mostly undersaturated, and the gas saturation tends to increase toward the deep coalbed. The J 2 x has a stronger methane adsorption and storage capacity than that of J 1 b and better physical properties, making CMB recovery easier. The coalbed reservoirs in middle-east of southern margin, eastern part and hinterland of Junggar Basin reach methane-rich to extremely methane-rich coalbeds and have strong ability to adsorb and store CBM. Coal seam gas shows generally, and the measured gas-bearing property is good. Low-rank CBM accounts for the majority of CBM resources in the basin. According to Langmuir volume, the gas provinces are classified into four types of blocks, i.e., CBM-poor (< 8 m 3 /t), CBM-bearing (8–15 m 3 /t), relatively CBM-rich (15–20 m 3 /t) and CBM-rich (> 20 m 3 /t). The relatively CBM-rich blocks cover block of well Qing 1 to Qi 8, Changji–Urumqi–Fukang area and slope belt of northwest margin to basin hinterland; while the CBM-rich blocks include most of eastern Junggar Basin. Since 2005, a series of special exploration and research of CBM have been carried out successively, and significant progress has been made in exploration of deep and shallow combination, conventional (gas) and unconventional (gas) combination. Recently shallow CBM exploration has achieved gas extraction at Dahuangshan coal mine, industrial gas flow wells in western Baiyanghe, and breakthrough of deep CBM exploration in Baijiahai area has been made, which confirmed the great development potential of low-rank CBM. The southern margin and the east of Junggar Basin have become the new frontier of low-rank CBM exploration in China. | Characteristics of low-rank coal reservoir and exploration potential in Junggar Basin: new frontier of low-rank CBM exploration in China | 10.1007/s13202-020-00923-3 |
2020-08-01 | The deposition of NH 4 HSO 4 on catalysts is one of the key issues for selective catalytic reduction of NO x . In this study, NH 4 HSO 4 was preloaded on catalysts, and the effects of MoO 3 and CeO 2 doping on the decomposition and reactivity of NH 4 HSO 4 on V 2 O 5 /TiO 2 catalysts are studied. The results show that the introduction of MoO 3 and CeO 2 significantly promoted NO x conversion on the V 2 O 5 /TiO 2 catalysts. Doping with MoO 3 could effectively enhance the S and H 2 O resistance of the catalysts. Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) analysis indicate that it is the strong chemical interactions between NH 4 HSO 4 and the catalysts that are adverse to the decomposition of NH 4 HSO 4 . However, doping with MoO 3 apparently inhibits these interactions, which significantly decrease the decomposition temperature of NH 4 HSO 4 . In situ FTIR experiments show that the NH 4 + in preloaded NH 4 HSO 4 could react with gaseous NO on catalysts, and doping with MoO 3 could facilitate the reaction rate. | Effects of MoO3 and CeO2 doping on the decomposition and reactivity of NH4HSO4 on V2O5/TiO2 catalysts | 10.1007/s11356-020-09343-6 |
2020-08-01 | Abstract We earlier discovered a new reaction in the chemistry of organoaluminum compounds (OACs), specifically, the formation of O -isobutyl acetals on low-temperature (–70°C) treatment of seven-membered lactones with a double (or more) molar amount of diisobutylaluminum hydride (DIBAH) in methylene chloride. To assess the boundaries for the formation of isobutyl acetals depending on the ring size, we involved in the low-temperature hydride reduction six-, eight-, and thirteen-membered lactones. To determine how the scope of the new reaction depends on the nature of the organoaluminum reagent, we tested triisobutylaluminum (TIBA). To determine how the formation of isobutyl acetals on low-temperature (–70°C) reduction with excess DIBAH in CH 2 Cl 2 depends on whether the starting ester is cyclic or acyclic and, if the former is the case, on the ring size in the ester, we used the acyclic methyl octadecanoate as the starting compound. It was found that the new reaction in the chemistry of AOC with DIBAH as the reducer is characteristic only of seven-membered lactones and atypical of acyclic methyl octadecanoate and ricinoleate (i.e. acids with the carbon chain length more than 6). | Influence of Some Factors on the Progress of a New Reaction in the Chemistry of Organoaluminum Compounds | 10.1134/S1070428020080047 |
2020-08-01 | Low-carbon ferromanganese (LC-FeMn) is an essential ingredient for making high-strength low-alloy steel and stainless steel. The conventional industrial-scale silicothermic method for the production of LC-FeMn comprises several energy intensive complex steps consuming about 2000 kWh/ton. We have attempted an improved silicothermic process, which is based on a single step smelting of optimized charge mix in the electric arc furnace. Thermochemical simulation of the smelting process by FactSage 6.4 showed significant effect of the charge mix basicity ( B = CaO/SiO 2 ) on manganese, iron, silicon and phosphorous distribution between the metal and slag. The optimum basicity was found to be 1.5 at the charge mix ratio i.e., Mn ore/lime/SiMn of 1:1:0.6 in the smelting tests. Under optimum conditions, the energy consumption was about 690 kWh/ton. This approach has potential benefits for the ferromanganese industry in terms of simpler and energy efficient process. | An Improved Process for the Production of Low-Carbon Ferromanganese in the Electric Arc Furnace | 10.1007/s12666-020-02010-x |
2020-08-01 | Abstract Given the observations at the section of the Ob river below the dam location of the Novosibirsk Hydropower Station, the calculations of water level dependence on water discharge and ice hole length in winter are carried out by the model of nonstationary hydrodynamic and ice-thermal processes. Some algorithm is developed that uses the dependence and allows us to determine the optimum discharge at the dam section providing the stable functioning of the river water intakes near Novosibirsk. The results of calculations are given for various values of the roughness coefficient of the lower ice cover. | A Comprehensive Mathematical Model of the Hydrodynamic and
Thermodynamic Processes in the Lower Pool of a Hydraulic Power Station | 10.1134/S1990478920030011 |
2020-08-01 | The present work isolated a CBF / DREB 1 gene from mangrove Bruguiera gymnorrhiza ( BgCBF 1) and compared its expression levels in various tissues under normal condition and cold stress, and in leaves exposed to various environmental stimuli. Results showed that the BgCBF1 deduced protein showed almost 100% similarities to that of AcCBF 1 from Aegiceras corniculatum and AmCBF 1 from Avicennia marina . Real-time quantitative PCR analysis showed that BgCBF 1 gene displayed constitute expression in leaf, stem and root samples of plantlets under normal condition, but with different expression levels and tissue preference. When exposed to cold, BgCBF 1 could be rapidly, slightly and transiently induced in all tissues. Furthermore, the BgCBF 1 gene in leaves displayed a transient and small induction after salt and drought (PEG) exposure, while exhibited relatively high up-regulated expression after the phytohormone abscisic acid (ABA) treatment. These results suggest that the BgCBF 1 gene may participate in the ABA mediated development and protection of plant against cold and drought. Further studies on its promoters and downstream genes will be needed to better understand its functions. | Isolation and expression analysis of a CBF transcriptional factor gene from the mangrove Bruguiera gymnorrhiza | 10.1007/s10646-020-02215-2 |
2020-08-01 | The study of hybrid composites has been increasing for several types of applications aimed at combining the properties of these materials and obtaining new outcomes. In the present article, low-velocity impacts were conducted in an intraply/yarn hybrid composite (hybridization in the yarn of the fabric) in order to assess its residual mechanical properties and relate them to damage propagation, comparing the results with other materials in the literature and determining the extent to which this type of hybridization influences the final result. Thus, we developed a composite with 11 layers consisting of 3 layers of bidirectional intraply/yarn Kevlar/glass hybrid fabric for the middle and outer layers of the laminate and 8 layers of bidirectional glass fiber fabric. The tests were conducted using two impact energies (61 and 76 J) until total penetration. The impact resistance of the hybrid yarn fabric improved, exhibiting a decline in the damage area, with low delamination and the possibility of repair. | Study of the Resistance Variation in Intraply/Yarn Kevlar/Glass Composite after Low-Velocity Impact | 10.1007/s11665-020-05015-1 |
2020-08-01 | The isothermal phase transformation behavior of thermally grown oxide scale of FeO on high-purity Fe was investigated under conditions of low oxygen potential. The phase transformation comprised three reactions, namely Fe 3 O 4 precipitation, magnetite seam formation, and the eutectoid decomposition. The nucleation rate of Fe 3 O 4 precipitation decreased with decreasing oxygen potential, whereas the incubation period for the eutectoid decomposition became longer. In contrast, magnetite seam formation was independent of the oxygen potential. The overall phase transformation was found to reach completion faster in an atmosphere with a lower oxygen potential. The effect of the oxygen potential on the phase transformation of FeO scale was rationalized by the different degree of supersaturation for Fe 3 O 4 precipitation, which plays a crucial role in the eutectoid reaction. | Phase Transformation of Thermally Grown FeO Formed on High-Purity Fe at Low Oxygen Potential | 10.1007/s11085-020-09979-2 |
2020-08-01 | The present paper is about an experimental evaluation of the terrestrial silicon single-crystalline solar PV module behavior under low gamma radiation. The simultanous proliferation of radioactive sources in Burkina Faso dominated by gamma type and the photovoltaic (PV) systems installations in both urban and rural areas justify this study. There is also high background radiation compared to normal in some region of the country. It has been shown that the photocurrent and the electric power increase while the photovoltage stays constant for an extremely low gamma radiation doses. This work proves that long time exposition to any low radiation can cause the reduction of the performance of the solar PV module. However for greater values of the dose, the photocurrent, the photovoltage and the electric power decrease. Hence, it is so important to protect PV equipments against gamma radiation by adjusting the PV installation height from the ground where high background radiation is notified or by putting reinforced concrete at their bottom faces. The two ways can be combinated adding the respect to radiation protection principle As Low As Reasonably Achievable (ALARA) . | Analysis of the Single-Crystalline Silicon Photovoltaic (PV) Module Performances Under Low γ - Radiation from Radioactive Source | 10.1007/s12633-019-00282-7 |
2020-08-01 | In this paper, three CrNiV series low-alloy steel with different C contents were fabricated by laser melting deposition (LMD) technique. Subsequently, the formability, microstructure and properties of LMD C x CrNiV low-alloy steel were evaluated. The results are as follows: with the increase in C content, the formability of low-alloy steel has decreased. All the samples were mainly composed of α-Fe (martensite) phase, and carbides were found to be dispersively distributed in the microstructure. As the C content increased, the martensite lath was remarkably refined, and the average grain size decreased from 2.76 to 2.33 μm. The tensile strength of the deposited samples increased by 21.58%, and the yield strength increased by 44.68%. As the formability of the deposited sample decreased, the elongation decreased by 35.93%. The average microhardness of deposited samples increased by 26.76%. When the content of C is higher, abrasion-resistant framework can be formed between carbides, and the peeling phenomenon during wear will be greatly reduced, the wear resistance is improved by 86.78%. | Formability, Microstructure and Properties of CxCrNiV Low-Alloy Steel Fabricated by Laser Melting Deposition | 10.1007/s11665-020-05027-x |
2020-08-01 | Liquid sloshing in storage tanks is of critical concern for the fluid management in space. In the present study, oscillation of liquid in a partially filled capsule storage tank was numerically studied using the volume of fluid method and taking into account the dynamic contact angle. The filling ratios of tank ranging from 10% to 90% and the gravity levels of 10 −3 g 0 and 0 g 0 were considered as the controlling variables. The temporal evolution of characteristic points of free surface and the law of oscillation frequencies were analyzed. The results show that for different filling ratios, the oscillations of free surfaces present different damping types, in which the small and large filling ratios correspond to the underdamping and the intermediate filling ratios to the critical damping. The present study provides fundamental insights into the free surface oscillations depending on the filling ratios and residual gravity level, which is useful for the corresponding utilization in space. | Liquid Sloshing in Partially Filled Capsule Storage Tank Undergoing Gravity Reduction to Low/Micro-Gravity Condition | 10.1007/s12217-020-09801-3 |
2020-08-01 | Abstract The effect of the rare-earth element (REE) content in dual-zeolite cracking catalysts on the conversion of n -dodecane and an n -dodecane–2-methylthiophene mixture (5000 ppm S) has been studied. The catalysts have been synthesized using zeolites Y and ZSM-5 modified with REEs and phosphorus, respectively, as the active component. It has been shown that the presence of REE oxides in zeolite Y (at a constant SiO 2 /Al 2 O 3 ratio) affects the catalytic activity of cracking catalysts based on this zeolite. The dependence of the light olefin yield on the REE oxide content in zeolite Y passes through a maximum at 2–3 wt %. The presence of a sulfur compound in an amount of 5000 ppm (in terms of sulfur) in the feedstock leads to a decrease in the model hydrocarbon conversion and the C 2 –C 4 olefin yield. In the presence of a sulfur compound, the change in the C 2 –C 4 olefin yield as a function of REE oxide content in zeolite Y is less pronounced than that in the case of individual n -dodecane cracking. | Coconversion of n-Dodecane and 2-Methylthiophene in the Presence of Dual-Zeolite Cracking Catalysts Containing Different Amounts of Rare-Earth Elements | 10.1134/S0965544120080113 |
2020-08-01 | Objectives Chemical Shift Encoded Magnetic Resonance Imaging (CSE-MRI)-based quantification of low-level (< 5% of proton density fat fraction—PDFF) fat infiltration requires highly accurate data reconstruction for the assessment of hepatic or pancreatic fat accumulation in diagnostics and biomedical research. Materials and methods We compare three software tools available for water/fat image reconstruction and PDFF quantification with MRS as the reference method. Based on the algorithm exploited in the tested software, the accuracy of fat fraction quantification varies. We evaluate them in phantom and in vivo MRS and MRI measurements. Results The signal model of Intralipid 20% emulsion used for phantoms was established for 3 T and 9.4 T fields. In all cases, we noticed a high coefficient of determination ( R -squared) between MRS and MRI–PDFF measurements: in phantoms <0.9924–0.9990>; and in vivo <0.8069–0.9552>. Bland–Altman analysis was applied to phantom and in vivo measurements. Discussion Multi-echo MRI in combination with an advanced algorithm including multi-peak spectrum modeling appears as a valuable and accurate method for low-level PDFF quantification over large FOV in high resolution, and is much faster than MRS methods. The graph-cut algorithm (GC) showed the fewest water/fat swaps in the PDFF maps, and hence stands out as the most robust method of those tested. | Low-level fat fraction quantification at 3 T: comparative study of different tools for water–fat reconstruction and MR spectroscopy | 10.1007/s10334-020-00825-9 |
2020-08-01 | The Liupanshan Basin constitutes a major portion of the northern North-South tectonic belt. The Lower Cretaceous strata in the Liupanshan Basin recorded the tectono-sedimentary evolution processes of this area and are pivotal for understanding the original sedimentary appearance of the Liupanshan Basin. In this work, we present a study of provenance and tectono-sedimentary evolution of the Liupanshan Basin during the Early Cretaceous. Integrated-paleocurrent directions, gravel clast compositions, and detrital zircon U-Pb isotopic analysis of the Lower Cretaceous Sanqiao and Heshangpu formations were applied to determine the provenance. The gravel clast compositions of Sanqiao Formation conglomerates (mainly including magmatic rocks, metamorphic rocks and limestones) display various features in different places, revealing different rock components of source areas. The paleocurrent directions of the Sanqiao and Heshangpu formations suggest that the sediments were transported from the basin margin to the center. Detrital zircons of two samples from the Huoshizhai Section (northwestern Liupanshan Basin) yield a dominant unimodal distribution from 420 to 500 Ma, suggesting a single-sourced provenance. Based on the above analyses, comparing to the magmatic records in the Qilian-Qinling orogenic belt, the detritus of the Sanqiao and Heshangpu formations were mainly from the proximal metamorphic and magmatic rocks of the Qilian-Qinling orogenic belt and the limestones of the archaic uplift. Combined with sedimentary characteristics, we concluded that the Liupanshan Basin experienced multi-stage evolution history: (1) the early rifting extension stage (Sanqiao Period), (2) the middle spanning and depression stage (Heshangpu-Early Naijiahe Period), and (3) the late extinction stage (Late Naijiahe Period). The evolution of Liupanshan Basin is closely related to that of Ordos Basin and it is further associated with tectonic transition of the northern North-South tectonic belt. | Provenance Analyses of Lower Cretaceous Strata in the Liupanshan Basin: From Paleocurrents Indicators, Conglomerate Clast Compositions, and Zircon U-Pb Geochronology | 10.1007/s12583-020-1324-8 |
2020-08-01 | Purpose The aim of this paper is to present and validate a framework for assessing healthcare facilities in low-resource settings to collect evidence and inform policies on the harmonisation, regulation and contextualised design of medical devices. Methods A literature review and focus groups with several experts of medical device design, clinical engineering, health technology assessment and management, allowed the creation of a protocol, comprising two parts: a semi-structured interview and electrical safety measures. Results Three hospitals were assessed in Benin and three in Uganda. All the health centres resulted to be facing typical challenges for low-resource settings, including the lack of funding, expertise, a well-established maintenance program, spare parts and consumables, and unreliable power supplies. Conclusion As there is a paucity of information regarding low-resource settings, the proposed framework can be used by clinical or biomedical engineers to assess and thereby propose actions for improving the conditions of healthcare settings. | A Framework for Assessing Healthcare Facilities in Low-Resource Settings: Field Studies in Benin and Uganda | 10.1007/s40846-020-00546-3 |
2020-08-01 | This study details the low-velocity impact and compression-after-impact (CAI) behaviour of flax fibre-reinforced polymer (FFRP) composites. The impact resistance, energy absorption efficiency and residual compressive strength as well as the damage pattern of the FFRP composites are compared with the corresponding features of glass fibre-reinforced polymer (GFRP) composites, and the effect of the stacking sequence of FFRP composites is also investigated. The results show that the cross-ply FFRP composites have the highest impact resistance, whereas the multi-directional ply composites have the lowest impact resistance but the highest energy absorption efficiency. The energy absorption efficiency of the FFRP composites is greater than that of the GFRP composites, but the penetration resistance and residual compressive strength of the FFRP composites are lower than those of the GFRP composites with the same stacking sequence, mainly due to the lower tensile strength and elongation at fracture of the FFRP composites. It is also reported that the damage pattern of the FFRP composites is localised cracking and delamination, unlike the overall delamination failure exhibited in the GFRP composites after CAI testing. Finally, the failure mechanisms of the FFRP and GFRP composites are detailed. | Low-Velocity Impact and Compression-After-Impact Behaviour of Flax Fibre-Reinforced Composites | 10.1007/s10338-019-00158-8 |
2020-08-01 | The study on Lower Cambrian dolostones in Tarim Basin can improve our understanding of ancient and deeply buried carbonate reservoirs. In this research, diagenetic fluid characteristics and their control on porosity evolution have been revealed by studying the petrography and in situ geochemistry of different dolomites. Three types of diagenetic fluids were identified: (1) Replacive dolomites were deviated from shallow burial dolomitizing fluids, which might probably be concentrated ancient seawater at early stage. (2) Fine-to-medium crystalline, planar-e diamond pore-filling dolomites (Fd1) were likely slowly and sufficiently crystallized from deep-circulating crustal hydrothermal fluids during Devonian. (3) Coarse crystalline, non-planar-a saddle pore-filling dolomites (Fd2) might rapidly and insufficiently crystallize from magmatic hydrothermal fluids during Permian. Early dolomitizing fluids did not increase the porosity, but transformed the primary pores to dissolution pores through dolomitization. Deep-circulating crustal hydrothermal fluids significantly increased porosity in the early stages by dissolving and then slightly decreased the porosity in the late stage due to Fd1 precipitation. Magmatic hydrothermal fluids only precipitated the Fd2 dolomites and slightly decreased the porosity. In summary, Devonian deep-circulating crustal hydrothermal fluids dominated the porosity evolution of the Lower Cambrian dolostone reservoir in the Tarim Basin. | The nature, type, and origin of diagenetic fluids and their control on the evolving porosity of the Lower Cambrian Xiaoerbulak Formation dolostone, northwestern Tarim Basin, China | 10.1007/s12182-020-00434-0 |
2020-08-01 | Purpose Intermittent catheterization (IC) is a proven effective long-term bladder management strategy for individuals who have lower urinary tract dysfunction. This study provides clinical evidence about multiple-reuse versus single-use catheterization techniques and if catheter choice can have an impact on health-related quality of life (HRQoL). Method A prospective, multi-center, clinical trial studied patients who currently practiced catheter reuse, and who agreed to prospectively evaluate single-use hydrophilic-coated (HC) (i.e. LoFric) catheters for 4 weeks. A validated Intermittent Self-Catheterization Questionnaire (ISC-Q) was used to obtain HRQoL. Reused catheters were collected and studied with regard to microbial and debris contamination. Results The study included 39 patients who had practiced IC for a mean of 10 years, 6 times daily. At inclusion, all patients reused catheters for a mean of 21 days (SD = 48) per catheter. 36 patients completed the prospective test period and the mean ISC-Q score increased from 58.0 (SD = 22.6) to 67.2 (SD = 17.7) when patients switched to the single-use HC catheters ( p = 0.0101). At the end of the study, 83% (95% CI [67–94%]) preferred to continue using single-use HC catheters. All collected reused catheters (100%) were contaminated by debris and 74% (95% CI [58–87%]) were contaminated by microorganisms, some with biofilm. Conclusion Single-use HC catheters improved HRQoL and were preferred over catheter reuse among people practicing IC. Catheter multiple-reuse may pose a potential safety concern due to colonization by microorganisms as well as having reduced acceptance compared to single use. Trial registry number ClinicalTrials.gov NCT02129738. | Intermittent catheterization with single- or multiple-reuse catheters: clinical study on safety and impact on quality of life | 10.1007/s11255-020-02435-9 |
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