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2021-05-01 | African swine fever virus (ASFV) has been circulating in China for more than two years, and it is not clear whether the biological properties of the virus have changed. Here, we report on our surveillance of ASFVs in seven provinces of China, from June to December, 2020. A total of 22 viruses were isolated and characterized as genotype II ASFVs, with mutations, deletions, insertions, or short-fragment replacement occurring in all isolates compared with Pig/HLJ/2018 (HLJ/18), the earliest isolate in China. Eleven isolates had four different types of natural mutations or deletion in the EP402R gene and displayed a non-hemadsorbing (non-HAD) phenotype. Four isolates were tested for virulence in pigs; two were found to be as highly lethal as HLJ/18. However, two non-HAD isolates showed lower virulence but were highly transmissible; infection with 10 6 TCID 50 dose was partially lethal and caused acute or sub-acute disease, whereas 10 3 TCID 50 dose caused non-lethal, sub-acute or chronic disease, and persistent infection. The emergence of lower virulent natural mutants brings greater difficulty to the early diagnosis of ASF and creates new challenges for ASFV control. | Emergence and prevalence of naturally occurring lower virulent African swine fever viruses in domestic pigs in China in 2020 | 10.1007/s11427-021-1904-4 |
2021-05-01 | Abstract Vysotskite is widespread in the Noril’sk-I deposit of Co–Ni–Cu sulfide massive and disseminated (“amygdaloid”) ores affected by posttrap low-grade metamorphism under conditions of prehnite–pumpellyite and zeolite (lomontite) facies, in association with ferruginous chlorite, babingtonite, ilvaite, greenalite, millerite, cummingtonite, grunerite, prehnite, pumpellyite, corrensite, polydymite, galena, and chalcopyrite. This metamorphosed sulfide ores facies formed at a low oxygen potential and the relatively increased fugacity of sulfide sulfur. Vysotskite here is extremely poor in platinum, but is enriched in nickel and partly in iron. Its average composition (wt %, n = 17): Pd 65.65 is Pt, 0.12; Rh, traces; Ni, 8.25; Fe, 0.95; Cu, 0.32; Co, 0.03; S, 25.03; and As 0.03; the sum is 100.38; the formula of this vysotskite is (Pd 0.79 Ni 0.18 Fe 0.02 Cu 0.01 ) 1 S 1 . In terms of mineral associations and chemical composition it corresponds to the Vysotskite discovered by A.D. Genkin and O.E. Zvyagintsev (1962). Thus, the vysotskite holotype is a metamorphogenic–hydrothermal vysotskite of the Noril’sk-I deposit with the composition (Pd, Ni)S. | The Vysotskite holotype: Metamorphogenic–Hydrothermal Vysotskite (Pd,Ni)S from the Noril’sk-1 Deposit | 10.3103/S0145875221030121 |
2021-05-01 | Introduction Although teriparatide (TPTD) and exercise may improve osteoporosis, muscle atrophy, and fat metabolism during ageing, the effects of treatment with a combination of TPTD and exercise on these factors remain unclear. Therefore, this study examined the effects of TPTD and exercise on bone, skeletal muscle, and fat in ovariectomized and tail-suspended rats. Materials and methods Seven-month-old female Wistar rats were ovariectomized and subjected to tail suspension. The rats were then randomized into one of the following four groups (n = 20/group) after 4 weeks: control group, treated with TPTD vehicle and no exercise; TPTD group (30 µg/kg TPTD, 3 days/week); Exercise group (treadmill at 12 m/min, 60 min/day, 5 days/week); and Combined group treated with TPTD and treadmill exercise. After 1 and 8 weeks of treatment, bone, skeletal muscle, and fat tissue parameters were evaluated. Results TPTD improved bone mineral density (BMD), bone structure, bone strength at the femoral metaphysis, and the percentage of skeletal muscle mass, and decreased the percentage of fat mass and the adipose volume in the bone marrow. Treadmill exercise increased BMD, bone strength of cancellous bone, and the percentage of skeletal muscle mass, and decreased the percentage of fat mass as seen on dual-energy X-ray absorptiometry. Furthermore, combined treatment significantly affected BMD, bone structure, and bone strength of cortical bone at the femoral diaphysis. Conclusion TPTD or treadmill exercise improved bone, skeletal muscle, and fat mass. Combination therapy with TPTD and exercise had synergistic effects on BMD, structure, and bone strength in ovariectomized, tail-suspended rats. | Teriparatide and exercise improve bone, skeletal muscle, and fat parameters in ovariectomized and tail-suspended rats | 10.1007/s00774-020-01184-0 |
2021-05-01 | Gaseous flow through ultra-tight porous media, e.g. shale and some high-performance insulation materials, is often rarefied, invalidating an analysis by the continuum flow theory. Such rarefied flows can be accurately described by the kinetic theory of gases which utilizes the Boltzmann equation and its simplified kinetic models. While discrete velocity methods have been successful in directly solving these equations, the immense potential of a particle-based solution of the variance-reduced Boltzmann-BGK (Bhatnagar–Gross–Krook) equation for rarefied flows in porous media has not been exploited yet. Here, a parallel solver based on the low variance deviational simulation Monte Carlo method is developed for 3D flows, which enables pore-scale simulations using digital images of porous media samples. The unique advantage of this particle-based formulation is in providing additional insights regarding the multi-scale nature of the flow and surface/gas interactions via two new parameters, i.e. pore and surface activity, respectively. Together, these two parameters can identify key flow properties of the porous media. The computational efficiency and accuracy of the current method has also been analysed, suggesting that this new solver is a powerful simulation tool to quantify flow properties of ultra-tight porous media. | Pore-Scale Study of Rarefied Gas Flows Using Low-Variance Deviational Simulation Monte Carlo Method | 10.1007/s11242-021-01588-0 |
2021-05-01 | Injecting carbon dioxide into coal seams for storage is an effective means to solve environmental problems such as the greenhouse effect. A history match study on a case of originally designed multi-well pilot CO 2 -ECBM field testing is introduced in this article. Numerical simulations were undertaken to study the primary productions of two existing offset wells, initial production of a newly drilled injection well, followed by two short-term CO 2 injection testing with a post-CO 2 production and a nitrogen slug between them. Through the history match study, a few specific model parameters, which were in no way to be directly measured or hardly interpreted through geophysical monitoring in the case of field scales, were accordingly determined. Parameters include initial reservoir water saturation, coal swelling, and shrinkage strains by the adsorption and desorption of gas components which govern coal cleat porosity and permeability changes, gas sorption time constants, and well skin factors during series of testing periods. The numerical simulations were additionally used to predict afterwards CO 2 storage volume, gaseous CO 2 distribution, and reservoir pressure in the field. Due to CO 2 price doubled up than its budget, meanwhile, hydraulic communication from upper stratum implied a leakage risk, the CO 2 injection was suspended. Available data recorded from this eventual micro-pilot case was worthwhile of being carefully studied. It would contribute to understanding the process of injecting CO 2 into relatively shallow but less saturated low-rank coal seams. | Effective means to alleviate the greenhouse effect: case study of history match simulations on a brief CO2 injection into less-deep low-rank coal seams | 10.1007/s12517-021-07104-4 |
2021-05-01 | Abstract For the first time in Russia, the Mokerov Institute of Ultra High Frequency Semiconductor Electronics, Russian Academy of Sciences (IUHFSE, RAS) developed, manufactured, and investigated three types of monolithic integrated circuits for the Ku and Ka-bands based on gallium nitride heterostructures on silicon substrates with a diameter of 100 mm. The measured microwave characteristics of the obtained microcircuits are presented. | Ku and Ka-band Gallium Nitride Monolithic Integrated Circuits on Silicon Substrates | 10.1134/S1063739721030045 |
2021-05-01 | The use of 3D digitizing tools is becoming the base for subject-specific products, such as the orthopaedic production process of orthoses and prostheses. This paper aims at comparing the metrological behaviour of low-cost devices (Kinect 1 and 2 by Microsoft, Structure Sensor by Occipital) and high-resolution active sensors (O&P Scan by Rodin4D, NextEngine Ultra HD, Konica Minolta Vivid 9i, GOM ATOS II 400 and Artec Leo) for the survey of human body parts. A calibrated flat plane and a test-field composed of eight calibrated spheres of different radii and placed at different heights were used to evaluate the standard quality parameters (flatness, probing errors in form and size and the standard deviation) for each device as recommended by the VDI/VDE 2634 guidelines. Subsequently, three different parts of a mannequin were surveyed as samples of human body parts. The results demonstrated the higher accuracy of fixed devices with respect to handheld ones, among which Artec Leo and Structure Sensor provided a satisfying level of accuracy for the orthopaedic application. Moreover, the handheld devices enabled performing a fast reconstruction of the mannequin parts in about 20 s, which is acceptable for a person that has to remain as still as possible. For this reason, the Structure Sensor was further tested with five motion approaches which identified that smooth motion provides the lowest deviation and higher reliability. The work demonstrated the appropriateness of handheld devices for the orthopaedic application requirements in terms of speed, accuracy and costs. | Comparison of geometrical accuracy of active devices for 3D orthopaedic reconstructions | 10.1007/s00170-021-06778-0 |
2021-05-01 | Recently, simultaneous measurements of the masses and the radii of neutron stars from X-ray observations by the Neutron Star Interior Composition Explorer (NICER) have been reported. In addition, gravitational wave detections from the mergers of neutron star binaries allowed us to estimate the tidal deformability of neutron stars. Based on these recent observations and our works, we review their implications for the masses, radii and tidal deformabilities of neutron stars. We also discuss the basic principles of the polytropic equations of state, including sound velocities, and the implications of those equations to the properties of neutron stars. | Neutron star properties from astrophysical observations | 10.1007/s40042-021-00084-4 |
2021-05-01 | As a type of water reducer, polycarboxylate superplasticizers (PCEs) has been widely used in the concrete industry. The concentration and molecule weight of PCEs have a profound impact on the performance of fresh concrete. Based on 1 H low-field nuclear magnetic resonance (NMR) spectroscopy, this paper developed a novel method for the determination of the concentration and characterization of the molecule weight of PCEs. Five types of PCEs with various ether to acid ratios (3:1 to 5:1) and functional groups were synthetized in laboratory conditions, and their molecular structures were characterized by size exclusion chromatography. PCE solutions with concentrations from 0 to 40% were measured using the Carr–Purcell–Meiboom–Gill sequence by 1 H low-field NMR. The results showed that the T 2 value of the main peak has a linear relation with the PCE concentration. The signal intensity of peaks whose T 2 values are smaller than 10 ms of the PCE solutions with a concentration of 20% is linearly correlated to the molecule weight of PCEs. | Application of 1H Low-Field NMR Spectroscopy for the Determination of the Concentration and Molecule Weight of Polycarboxylate Superplasticizers | 10.1007/s10812-021-01176-6 |
2021-05-01 | Abstract For the first time, experiments were performed using an ad hoc laboratory setup to study the mechanisms of the effects of low-intensity ultrasound on toxigenic cyanobacteria Synechocysctis sp . that prevail in the northwestern part of Russia. It is found that ultrasound triggers two stress-protective metabolic mechanisms of toxigenic cyanobacteria: (1) synthesis of polysaccharides and proteins to increase the thickness of cell walls and mucous membranes; (2) synthesis of toxins to suppress the external influence. Both mechanisms are extremely energy-consuming, depleting the vital resources of cyanobacteria and accelerating the process of cell death. | The Effects of Low-Intensity Ultrasound on Toxigenic Cyanobacteria | 10.1134/S1028334X21050147 |
2021-05-01 | Tambaqui ( Colossoma macropomum ) are a model species for tropical fish physiology, but details are lacking about their ionoregulatory response to acid waters. To provide specifics, we measured unidirectional Na + fluxes in low pH waters. Sodium influx ( $$J_{{{\text{in}}}}^{{{\text{Na}}}}$$ J in Na ) was uninhibited during acute exposure to pH 4.5 and 3.5, and Na efflux ( $$J_{{{\text{out}}}}^{{{\text{Na}}}}$$ J out Na ) rose only slightly at pH 3.5; net Na + flux ( $$J_{{{\text{net}}}}^{{{\text{Na}}}}$$ J net Na ) remained positive at all pH. Similarly, during 24 h transfer to pH 3.5 $$J_{{{\text{in}}}}^{{{\text{Na}}}}$$ J in Na , $$J_{{{\text{out}}}}^{{{\text{Na}}}}$$ J out Na , and $$J_{{{\text{net}}}}^{{{\text{Na}}}}$$ J net Na were unchanged at all times. Taking a closer look at the mechanism of Na + transport in the gills of tambaqui we found that $$J_{{{\text{in}}}}^{{{\text{Na}}}}$$ J in Na was uninhibited by HMA, a Na + /H + -exchanger blocker, and Benzamil, a Na + -channel inhibitor, casting doubt on their role in Na + uptake in this fish. Measurement of Na + /K + -ATPase (NKA) and H + -ATPase (VHA) activity showed that neither changed at low pH compared to measurements at pH 6.5. Western blot analysis of ATPase expression saw no changes in amount of NKA and VHA at low pH, and immunohistochemistry showed expression of both NKA and VHA on lamellae and interlamellar region of tambaqui gills and that both proteins co-localized to the same gill cells. Location of expression also did not change in low pH water. Amazingly, tambaqui seem unaffected by pH 3.5 water, making them one of the most acid-tolerant fish species examined so far. In addition, they appear to share key ionoregulatory traits with other fish of the order Characiformes, which suggest a common origin for the ionoregulatory attributes. | Exposure to pH 3.5 water has no effect on the gills of the Amazonian tambaqui (Colossoma macropomum) | 10.1007/s00360-021-01349-x |
2021-05-01 | HIV-1 transactivator protein (Tat) induces tight junction (TJ) dysfunction and amyloid-beta (Aβ) clearance dysfunction, contributing to the development and progression of HIV-1-associated neurocognitive disorder (HAND). The Rho/ROCK signaling pathway has protective effects on neurodegenerative disease. However, the underlying mechanisms of whether Rho/ROCK protects against HIV-1 Tat-caused dysfunction of TJ and neprilysin (NEP)/Aβ transfer receptor expression have not been elucidated. C57BL/6 mice were administered sterile saline (i.p., 100 μL) or Rho-kinase inhibitor hydroxyfasudil (HF) (i.p., 10 mg/kg) or HIV-1 Tat (i.v., 100 μg/kg) or HF 30 min before being exposed to HIV-1 Tat once a day for seven consecutive days. Evans Blue (EB) leakage was detected via spectrophotometer and brain slides in mouse brains. The protein and mRNA levels of zonula occludens-1 (ZO-1), occludin, NEP, receptor for advanced glycation end products (RAGE), and low-density lipoprotein receptor-related protein 1 (LRP1) in mouse brain microvessels were, respectively, analyzed by Western blotting and quantitative real-time polymerase chain reaction (qRT-PCR) analyses. Exposure of the mice to HIV-1 Tat increased the amount of EB leakage, EB fluorescence intensity, blood–brain barrier (BBB) permeability, as well as the RAGE protein and mRNA levels, and decreased the protein and mRNA levels of ZO-1, occludin, NEP, and LRP1 in mouse brain microvessels. However, these effects were weakened by Rho-kinase inhibitor HF. Taken together, these results provide information that the Rho/ROCK signaling pathway is involved in HIV-1 Tat-induced dysfunction of TJ and NEP/Aβ transfer receptor expression in the C57BL/6 mouse brain. These findings shed some light on potentiality of inhibiting Rho/Rock signaling pathway in handling HAND. | Rho-kinase inhibitor hydroxyfasudil protects against HIV-1 Tat-induced dysfunction of tight junction and neprilysin/Aβ transfer receptor expression in mouse brain microvessels | 10.1007/s11010-021-04056-x |
2021-05-01 | The paper presents the results of the transmission electron microscopy of the evolution of the dislocation substructure (DSS) of the polycrystalline ordered and disordered Pd 3 Fe alloys with low-stable structure and phase compositions. A flow chart is suggested for the transformation of the dislocation substructures during a transition from one stage to another. These stages are indicated on the stress-strain curves of the Pd 3 Fe alloy. It is found that in the case of both disordered and ordered alloys, each deformation stage is characterized by a specific dislocation substructure, which is the main deformation medium for each stage. A transition from one DSS type to another occurs at a certain range of the deformation degree. The DSS type characteristic to a given stage of deformation appears at a preceded stage and its amount increases with the deformation growth. At a given deformation stage, this amount is the highest, while during the transition to another stage, it gradually lowers and disappears. In the ordered alloys, the DSS types differ from those in the disordered alloys at the same deformation stage. It is shown that at each deformation stage, there are specific dislocation substructures or deformation media. During the transition to a new stage, the transition to a new structural deformation media occurs, and these media exist together. This is characteristic to the low-stability state of the whole system. | Evolution of Dislocation Substructure in Deformed Ordered and Disordered Pd3Fe Alloys in Low-Stability State | 10.1007/s11182-021-02305-6 |
2021-05-01 | The aim was to assess the results of primary anastomosis (PA) compared to enterostomy (ES) in infants with spontaneous intestinal perforation (SIP) and a weight below 1000 g. Between 2014 and 2016, enterostomy was routinely carried out on extremely low birth weight (ELBW) patients with SIP. From 2016 until 2019, all patients underwent anastomosis without stoma formation. We compared outcome and complications in both groups. Forty-two patients with a median gestational age of 24.3 weeks and a birth weight of 640 g with SIP were included. Thirty patients underwent PA; ES was performed in 12 patients. Overall in-hospital mortality was 11.9% (PA: 13.3%, ES: 8.3%). Reoperations due to complications became necessary in 10/30 patients with PA and 4/12 patients with ES. Length of stay was 110.5 days in the PA group and 124 days in the ES group. Median weight at discharge was higher in the PA group (PA: 2258 g, ES: 1880 g, p = .036). Conclusion : Primary anastomosis is a feasible treatment option for SIP in infants < 1000 g and may have a positive impact on weight gain and length of hospitalization. However, further studies on selection criteria for PA are necessary. What is Known: • Enterostomy (ES) and primary anastomosis (PA) are feasible treatment options in preterm infants with spontaneous intestinal perforation (SIP). • Stomal complications or failure to thrive due to poor food utilization can pose significant problems. What is New: • Primary anastomosis in case of SIP is equal to enterostomy in terms of mortality and revision rate; however, length of stay and weight gain can be presumably positively influenced. • Primary anastomosis is a valid treatment option even for patients weighing less than 1000 g. | Primary anastomosis as a valid alternative for extremely low birth weight infants with spontaneous intestinal perforation | 10.1007/s00431-021-03926-2 |
2021-05-01 | Acute lung injury and acute respiratory distress syndrome can occur as a result of sepsis. Cardiac dysfunction is a serious component of multi-organ failure caused by severe sepsis. Telomere shortening is related to several heart diseases. Telomeres are associated with the shelterin protein complex, which contributes to the maintenance of telomere length. Low-power infrared lasers modulate mRNA levels of shelterin complex genes. This study aimed to evaluate effects of a low-power infrared laser on mRNA relative levels of genes involved in telomere stabilization and telomere length in heart tissue of an experimental model of acute lung injury caused by sepsis. Animals were divided into six groups, treated with intraperitoneal saline solution, saline solution and exposed to a low-power infrared laser at 10 J cm −2 and 20 J cm −2 , lipopolysaccharide (LPS), and LPS and, after 4 h, exposed to a low-power infrared laser at 10 J cm −2 and 20 J cm −2 . The laser exposure was performed only once. Analysis of mRNA relative levels and telomere length by RT-qPCR was performed. Telomere shortening and reduction in mRNA relative levels of TRF1 mRNA in heart tissues of LPS-induced ALI animals were observed. In addition, laser exposure increased the telomere length at 10 J cm −2 and modulated the TRF1 mRNA relative levels of at 20 J cm −2 in healthy animals. Although the telomeres were shortened and mRNA levels of TRF1 gene were increased in nontreated controls, the low-power infrared laser irradiation increased the telomere length at 10 J cm −2 in cardiac tissue of animals affected by LPS-induced acute lung injury, which suggests that telomere maintenance is a part of the photobiomodulation effect induced by infrared radiation. | Low-power infrared laser modulates telomere length in heart tissue from an experimental model of acute lung injury | 10.1007/s43630-021-00051-9 |
2021-05-01 | In the development of a land-sea coordination management strategy, it is necessary to analyze pollution sources and loads of pollutants entering the sea. This study estimated the sources and transport of total nitrogen (TN) and total phosphorus (TP) entering Bohai Bay in Tianjin, a lower plain urban watershed, using a SPAtially Referenced Regression On Watershed attributes (SPARROW) model. We calibrated the model using TN and TP data from 26 and 27 sites, respectively. The results demonstrated that the R 2 values of TN and TP were both above 0.99. In 2013, the TN load delivered to Bohai Bay was 21,320 ton, which could be traced to various sources: upstream (39%), industrial discharge (10%), sewage discharge (34%), fertilizer application (3%), livestock breeding (7%), aquaculture (5%), and rural communities (2%). The TP load delivered to Bohai Bay was 1504 ton, which originated from upstream (33%), industrial discharge (5%), sewage discharge (21%), fertilizer application (5%), livestock breeding (12%), aquaculture (10%), and rural communities (14%). Rational management of the water resources in streams, enhancement of water circulation between rivers and wetlands, and making full use of the effect of both land and water on pollutant retention are the suitable strategies in watershed management, reducing marine pollution. | Estimate of nutrient sources and transport into Bohai Bay in China from a lower plain urban watershed using a SPARROW model | 10.1007/s11356-020-11932-4 |
2021-05-01 | Background Low-cost sensors have the potential to democratize air pollution information and supplement regulatory networks. However, differentials in access to these sensors could exacerbate existing inequalities in the ability of different communities to respond to the threat of air pollution. Objective Our goal was to analyze patterns of deployments of a commonly used low-cost sensor, as a function of demographics and pollutant concentrations. Methods We used Wilcoxon rank sum tests to assess differences between socioeconomic characteristics and PM 2.5 concentrations of locations with low-cost sensors and those with regulatory monitors. We used Kolomogorov–Smirnov tests to examine how representative census tracts with sensors were of the United States. We analyzed predictors of the presence, and number of, sensors in a tract using regressions. Results Census tracts with low-cost sensors were higher income more White and more educated than the US as a whole and than tracts with regulatory monitors. For all states except for California they are in locations with lower annual-average PM 2.5 concentrations than regulatory monitors. The existing presence of a regulatory monitor, the percentage of people living above the poverty line and PM 2.5 concentrations were associated with the presence of low-cost sensors in a tract. Significance Strategies to improve access to low-cost sensors in less-privileged communities are needed to democratize air pollution data. | On the distribution of low-cost PM2.5 sensors in the US: demographic and air quality associations | 10.1038/s41370-021-00328-2 |
2021-05-01 | Cardiovascular events can occur after deferred revascularization, and malondialdehyde-modified low-density lipoprotein (MDA-LDL) has been suggested to be an atherogenic marker. We investigated the relationship between serum MDA-LDL levels and clinical outcomes in patients with fractional flow reserve (FFR)-guided deferral of revascularization. Among 3084 patients undergoing coronary angiography, we retrospectively analyzed 127 patients with intermediate stenosis and deferred revascularization based on FFR > 0.80. Median follow-up interval was 30.4 months, and serum MDA-LDL was measured prior to the measurement of FFR. We evaluated the composite of major adverse cardiac events (MACEs), including cardiac death, myocardial infarction, ischemia-driven deferred lesion revascularization, and any revascularization. MACEs occurred in 18 (14.2%) patients. The MACE group presented with significantly higher MDA-LDL levels than the non-MACE group (134.9 ± 33.3 U/L vs. 95.6 ± 32.2 U/L, P < 0.001). In analysis of the receiver operating characteristics curve for the prediction of MACEs, MDA-LDL presented a significantly larger area under the curve than low-density lipoprotein-cholesterol (LDL-C; 0.810 vs. 0.687, P = 0.042). Univariate Cox regression analysis indicated a significant relationship between MACEs and MDA-LDL (per 10 U/L, HR 1.20; P = 0.004), as did the multivariate model (per 10 U/L, HR 1.17; P = 0.019). When compared according to the median LDL-C (98 mg/dL), the MACE group had significantly higher MDA-LDL in both the high (147.2 ± 27.3 U/L vs. 113.9 ± 31.2 U/L, P = 0.001) and low (103.2 ± 27.3 U/L vs. 80.2 ± 24.0 U/L, P = 0.045) LDL-C groups. Serum MDA-LDL levels were associated with cardiac events in patients with deferral of revascularization based on FFR. | Impact of malondialdehyde-modified low-density lipoprotein on clinical outcomes after fractional flow reserve-guided deferral of revascularization | 10.1007/s00380-020-01731-9 |
2021-05-01 | Experiments to characterize the constant-rate gas depleted production behavior in core samples were performed to study the areal gas flowing mechanism of a high-pressure low-permeability heterogeneous gas reservoir, including a newly designed long-core experiment on areal heterogeneity constant-rate gas depleted production considering fracturing. In the experiments, the fluid pressure increased up to 45 MPa, and the cores of the near-wellbore high permeability area before and after fracturing and the cores of the low permeability non fractured area were connected in series to simulate the gas flowing process of the dual-area composite gas reservoir. When the irreducible water saturation is considered, the gas permeability in a high permeability area cater fracturing increased threefold. Experimental results indicated that the pressure difference in the near-wellbore high permeability area decreased rapidly after fracturing and increased in the low permeability area. The recovery:factor of each area increased titter fracturing. Fracturing could have a significant effect on increasing the recovery factor when the average permeability is relatively low. The greater the gas rate, the higher is the built-up pressure alter shut-in. Fracturing in the near-wellbore area may cause a significant decrease in the shut-in built-up pressure value. | Experimental Study on Areal Flowing During Depletion of a High-Pressure Heterogeneous Gas Reservoir | 10.1007/s10553-021-01259-2 |
2021-05-01 | Abstract The antioxidant properties, spectral characteristics and the composition of lipids isolated from marigold flowers and sea buckthorn fruits and from their 50% water-propyleneglycol (WPG) extracts were studied. Significant quantitative differences in the inhibitory efficiency, the quantitative ratio of lipid fractions and the presence of biologically active substances in their chloroform solution were revealed depending on the polarity of the eluent. This stipulates the ability of the lipid component of plant objects to take part in the regulation of oxidation at different stages of the process. It was confirmed by the analysis of the kinetic curves of the peroxide accumulation using the KINS software package and mathematical processing of UV spectra of lipid solutions by the Gauss method. | Inhibitory Efficiency of the Lipid Component of Plant Objects Depending on the Polarity of the Eluent | 10.1134/S0006350921030179 |
2021-05-01 | Study design Prospective experimental uncontrolled trial. Background Vertebrogenic pain is a frequently underestimated cause of chronic low back pain (LBP). Vertebral endplate degeneration, characterized by cortical bone damage and subchondral bone inflammatory reaction, is a significant source of LBP, the responsible of the pain transmission being the Basivertebral Nerve (BVN). Radiofrequency ablation of the BVN (BVA) leads to thermal injury of nerve tissue and interruption of the of chronic vertebrogenic pain transmission. Purpose The aim of this study is to evaluate the effectiveness, in terms of pain and disability reduction, of percutaneous (BVA) in treating patients affected by vertebrogenic chronic LBP. Moreover, as a secondary endpoint, the purpose is to assess the feasibility and safety of a percutaneous CT-guided technique. Methods We performed percutaneous CT-guided BVN ablation in 56 consecutive patients presenting with vertebrogenic chronic LBP in local anesthesia using an articulating bipolar radiofrequency electrode (STAR™ Tumor Ablation System Merit). A 1-month follow-up MRI was performed to evaluate the ablation area in order to assess the target success of the procedure. A 3-month follow-up CT study was performed to evaluate bone mineral density in order to exclude structural bone abnormalities that might have been induced by the treatment. Pre- and post-procedure pain and disability levels were measured using the visual analogue scale (VAS) and Oswestry Disability Index (ODI). A 2-cm improvement threshold was set as clinical success for the VAS score and a 10-point improvement threshold was set as clinical success for the ODI score. Results At 3- and 12-month follow-up, VAS and ODI scores decreased significantly compared to baseline. Clinical success was reached in 54/56 patients (96.5%) for pain and 54/56 patients (96.5%) for disability, exceeding significantly the MCID. CT-assisted targeting of the ablation zone was determined successful in 100% of patients. Mean operative time was 32 min. No immediate or delayed complications were detected. Conclusions Percutaneous CT-guided intra-osseous BVA seems to be a safe, fast, and powerful technique for pain relief in patients with vertebrogenic chronic LBP, when the selection of patients is based on a multidisciplinary approach including both conventional Diagnostic Radiology and Nuclear Medicine imaging. | Intra-osseous basivertebral nerve radiofrequency ablation (BVA) for the treatment of vertebrogenic chronic low back pain | 10.1007/s00234-020-02577-8 |
2021-05-01 | Negative correlations between elements, molecules, or minerals can indicate a variety of geochemical processes, such as ion exchange, incongruent mineral precipitation/dissolution, and redox reactions. However, compositional data (those composed of relative parts) can also exhibit negative correlations simply due to displacement of one part by another, such as the addition of sodium chloride lowering the concentration of all ions other than sodium and chloride in a solution. Apart from this practical problem, the question is more general: how to address the relationships between components in data carrying relative information. For this purpose, the symmetric pivot coordinates were developed which allow for the identification of both positive and negative correlations between two parts in compositional data in terms of their relative dominance to the other parts. Accordingly, the symmetric pivot coordinate approach aggregates all of the logratios with those two parts of interest. This may not be desirable if data quality problems occur, because such parts would contribute the same weight to the coordinate as parts with good data quality. As a way out, the new method of weighted symmetric coordinates focusing on pairwise associations is proposed. In this approach, variables with large logratio variances are down-weighted to suppress their effect on the remaining variables, which is also demonstrated in a small simulation study. Finally, the weighted symmetric pivot coordinates are applied to chemistry data from a series of waste water samples from oil and gas wells produced from the lower Eagle Ford Group in the U.S. Gulf Coast Basin. In particular, strong negative correlations between ions are examined using this method to reveal processes which occur as a function of depth, including clay diagenesis, de-dolomitization, kerogen maturation, and sulfate and carbonate mineral saturation. | Weighted Symmetric Pivot Coordinates for Compositional Data with Geochemical Applications | 10.1007/s11004-020-09862-5 |
2021-05-01 | Water quality index and chemometric methods were employed to assess the groundwater quality and contamination sources in the upper Ganges basin (UGB) and lower Ganges basin (LGB) as groundwater is a sole source for drinking, domestic and agricultural uses. Groundwater samples were collected from UGB ( n = 44) and LGB ( n = 26) and analysed for physicochemical parameters. Groundwater in this basin is desirable (51%) to permissible (TDS < 1000 mg/l, 96%) classes for drinking. Chemical constituents in the groundwater are lower than the maximum allowable limit recommended by the WHO for drinking except K. Drinking water quality index (DWQI) values reveal that groundwater belongs to excellent (89%) and good (10%) classes. However, the high concentrations of Fe and Mn in 61 and 77% of samples, respectively, restrict the usage for drinking according to USEPA recommendations. Both LGB and UGB groundwater in shallow wells have elevated concentration of TDS, EC and other ions (Ca 2+ , Cl - and SO 4 2- in LGB; major ions, NO 3 - , PO 4 3- , F - , Fe and Mn in UGB) and imply the influences of anthropogenic activities. Principal component analysis and hierarchical cluster analysis reiterated that groundwater quality is affected by the anthropogenic activities as well as mineral dissolutions (carbonate and silicate minerals). This study highlighted that the infiltration of wastewater from various contamination sources likely triggered the dissolution of the minerals in the vadose zone that resulted in the accumulation of ions in the shallow aquifer. An effective management plan is essential to protect this shallow aquifer. | Application of water quality index and chemometric methods on contamination assessment in the shallow aquifer, Ganges River basin, India | 10.1007/s11356-020-12270-1 |
2021-05-01 | Invertebrates change the metabolite concentrations in their bodies to adapt to environmental salinity. The kuruma shrimp Marsupenaeus japonicus is one such invertebrate. It lives in coastal areas and is also known to change free amino acid concentrations depending on environmental salinity. To examine the relationship between the concentrations of metabolites, including amino acids, in the kuruma shrimp with environmental salinity, metabolome analysis was performed on the abdominal muscle of shrimps acclimated at 17, 34 and 40‰ salinity for 24 h. Principal component analysis revealed that the accumulation patterns of metabolites using the 111 metabolites detected in the shrimps exposed to different salinities were depicted in a salinity-dependent manner. The concentrations of alanine and glutamine were increased following exposure to increasing levels of salinity, suggesting that these free amino acids function in intracellular osmoregulation of the kuruma shrimp. Furthermore, the concentration of glycolytic metabolites was significantly decreased at high salinity. The concentrations of most of the metabolites related to the tricarboxylic acid (TCA) cycle also tended to decrease at high salinity. Considering the levels of expression of the genes related to various metabolic pathways, it seems that glycolysis is accelerated at high salinity. | Changes in metabolite concentrations in the abdominal muscle of the kuruma shrimp Marsupenaeus japonicus in response to different salinities | 10.1007/s12562-021-01512-x |
2021-05-01 | Landslide susceptibility zonation (LSZ) map is prepared for a part of the lower Himalayas using the fuzzy cosine amplitude method. The prepared LSZ map is validated both statistically and physically, and it is found that around 30% of the study area lies in zones of high to very high landslide susceptibility. To correlate the Himalayan seismicity with the landslide hazard, the prepared LSZ map is further assessed in terms of the impact of fault distance on the occurrence and spatial distribution of landslides in the study area. The results quantify a strong inverse correlation between fault distance and the probability of landslide occurrence. A high coefficient of determination ( R 2 = 0.986) indicates that the equation can realistically predict the impact of fault distance on the study area's landslide occurrence. Further, landslide relative frequency (LRF) method is used to evaluate the statistical contribution of fault distance toward overall landslide susceptibility for the study area. It is found that distance from any major tectonic feature is a significant landslide causative parameter, with a relative importance of 21%. The prepared LSZ map will be valuable for decision-makers during smart town planning and sustainable development in the study area. | Landslide Susceptibility Zonation With Special Emphasis on Tectonic Features for Occurrence of Landslides in Lower Indian Himalaya | 10.1007/s12524-020-01285-3 |
2021-04-29 | We report in-situ dating, and Hf and O-isotope studies of zircon crystals, together with electron microprobe imaging of garnet crystals from a migmatitic diorite containing noritic globules, in the Ursuya massif (French Pyrenees). Diorite zircon crystals have old inherited cores and 295 ± 2 Ma rims, while those in the norite are homogeneous, with lower U and Pb, and higher Th and Th/U ratios than in the diorite zircon rims. The 295 Ma dates represent the crystallization age of hybridised crustal melts. Norite zircon crystals have similar ages (298 ± 3 Ma) to the diorite zircon rims, interpreted as the crystallization age of the norite. Hf isotopes indicate that the noritic magmas were already crustally contaminated prior to intrusion at their present locations. The contrasting behaviours of slow- and fast-diffusing species within garnet (e.g. P vs Ca) caused sharp P and diffuse Ca core-rim transitions. Modelling of garnet Ca diffusion profiles suggests a duration of 2 ± 1 Myr for the magma interactions in the deep crust. Integrated with granite dating, these data provide insights into pulsations in the regional thermal event that concluded the Hercynian orogenic cycle. | Age, duration and mineral markers of magma interactions in the deep crust: an example from the Pyrenees | 10.1007/s00410-021-01789-2 |
2021-04-29 | Many studies have been carried out to investigate the cyclic water injection (CWI) in enhancing oil recovery, while most of the target reservoirs are conventional, and the study for CWI in application to ultralow permeability reservoir is limited. In this study, a combination of experiment and numerical simulation was used to evaluate the performances of CWI in ultralow permeability reservoir. The results indicate that short pressurizing period but long depressurizing period gives the low possibility of water breakthrough and sufficient time for oil/water exchanging and redistribution, which achieves better oil recovery efficiency. In addition, high pressurizing pressure is a good compensation to the reservoir energy, and pushes the water into the far region to displace more oil. The optimized operation parameters for the core-scale experiments are further evaluated with numerical simulation of a realistic ultralow permeability reservoir located in Ordos basin, China, and consistent results between experiment and simulation are found. In the simulation, the optimal injection period and injection pressure during the pressurizing cycle are 20 days and 14 MPa, respectively; the optimal injection period and injection pressure during the depressurizing cycle are 60 days and 2 MPa, respectively. Good field response has been achieved after the implementation of the optimized parameters. This work, for the first time, systematically studies the performances of CWI technique in application to ultralow permeability reservoirs both at core scale and reservoir scale, and it provides theoretical and practical implications for enhancing oil recovery in similar types of ultralow permeability oil reservoirs. | Experimental and simulation investigations of cyclic water injection in low-permeability reservoir | 10.1007/s12517-021-07129-9 |
2021-04-28 | Background Glioblastoma is the most frequent and high-grade adult malignant central nervous system tumor. The prognosis is still poor despite the use of combined therapy involving maximal surgical resection, radiotherapy, and chemotherapy. Metabolic reprogramming currently is recognized as one of the hallmarks of cancer. Glutamine metabolism through glutaminolysis has been associated with tumor cell maintenance and survival, and with antioxidative stress through glutathione (GSH) synthesis. Methods In the present study, we analyzed the glutaminolysis-related gene expression levels in our cohort of 153 astrocytomas of different malignant grades and 22 non-neoplastic brain samples through qRT-PCR. Additionally, we investigated the protein expression profile of the key regulator of glutaminolysis (GLS), glutamate dehydrogenase (GLUD1), and glutamate pyruvate transaminase (GPT2) in these samples. We also investigated the glutathione synthase (GS) protein profile and the GSH levels in different grades of astrocytomas. The differential gene expressions were validated in silico on the TCGA database. Results We found an increase of glutaminase isoform 2 gene ( GLSiso2 ) expression in all grades of astrocytoma compared to non-neoplastic brain tissue, with a gradual expression increment in parallel to malignancy. Genes coding for GLUD1 and GPT2 expression levels varied according to the grade of malignancy, being downregulated in glioblastoma, and upregulated in lower grades of astrocytoma (AGII–AGIII). Significant low GLUD1 and GPT2 protein levels were observed in the mesenchymal subtype of GBM. Conclusions In glioblastoma, particularly in the mesenchymal subtype, the downregulation of both genes and proteins (GLUD1 and GPT2) increases the source of glutamate for GSH synthesis and enhances tumor cell fitness due to increased antioxidative capacity. In contrast, in lower-grade astrocytoma, mainly in those harboring the IDH1 mutation, the gene expression profile indicates that tumor cells might be sensitized to oxidative stress due to reduced GSH synthesis. The measurement of GLUD1 and GPT2 metabolic substrates, ammonia, and alanine, by noninvasive MR spectroscopy, may potentially allow the identification of IDH1 mut AGII and AGIII progression towards secondary GBM. | Glutaminolysis dynamics during astrocytoma progression correlates with tumor aggressiveness | 10.1186/s40170-021-00255-8 |
2021-04-28 | In the present work, electro-optical and electronic properties of 4-n-pentyl- $$4^{\prime }$$ 4 ′ -cyanobiphenyl (5CB) and $$4^{\prime }$$ 4 ′ -cyano-4-n-pentyl-p-terphenyl (5CT) liquid crystal molecules have been investigated. The 5CB compound transforms from crystal to nematic phase at 24 $$^\circ $$ ∘ C and nematic to isotropic phase at 35.3 $$^\circ $$ ∘ C while 5CT compound transforms from crystal to nematic phase at 130 $$^\circ $$ ∘ C and nematic to isotropic phase at 239 $$^\circ $$ ∘ C. Molecular geometry of 5CB and 5CT have been optimised by DFT method with 6-31G(d,p) basis set. Binding energies acting between dimers have been calculated. Mulliken and natural population analyses have been done. The HOMO–LUMO surfaces, molecular and thermodynamic properties have been examined. The excitation energy and oscillator strength have been calculated by TD-DFT/B3LYP/6-31G(d,p) method. All the investigated parameters of 5CT have been compared with that of 5CB molecule. Results have been used to elucidate the electro-optical and electronic properties of 5CB and 5CT molecules. | Electronic and electro-optical properties of 5CB and 5CT liquid crystal molecules: A comparative DFT study | 10.1007/s12043-021-02114-z |
2021-04-27 | We applied the method of coarse-graining the intermolecular vibrations to molecular heterodimers assembled by double hydrogen bonding. This method is based on principal component analysis, by which the original atomic displacement vectors are projected onto a lower-dimensional space spanned by a basis set of translations, librations, and intramolecular vibrations of the constituent molecules. Compared with homodimers, the following points are particularly noted: (1) alignment of the constituent molecules in a non-symmetric atomic arrangement of the whole system and (2) the scheme of reordering the bases to construct an optimal coarse-grained space. We tested three schemes for reordering the intramolecular vibration vectors to determine that the best one is equivalent to size reduction based on the singular value decomposition. The coarse-graining analysis affords three parameters, Φ intra , Φ inter , and Φ app , which are relevant to the mechanical nature of the molecular assembly. The Φ intra values account for the internal stiffness of molecules, while the Φ inter values are true stiffness constants of the intermolecular force and show a good correlation with the association energies of the dimers. The Φ app values are the apparent intermolecular stiffness smaller than Φ inter , as a result of compensation for neglecting intramolecular vibrations. All these values are consistent with each other under the coupled oscillator model, showing that the present coarse-graining analysis is valid for heterodimers as well as homodimers. | Optimizing a coarse-grained space for approximate normal-mode vibrations of molecular heterodimers | 10.1007/s00894-021-04743-y |
2021-04-26 | We derive explicit expressions for a specific subclass of Jackiw-Teitelboim (JT) gravity bilocal correlators, corresponding to degenerate Virasoro representations. On the disk, these degenerate correlators are structurally simple, and they allow us to shed light on the 1/C Schwarzian bilocal perturbation series. In particular, we prove that the series is asymptotic for generic weight h ∉ − ℕ/2. Inspired by its minimal string ancestor, we propose an expression for higher genus corrections to the degenerate correlators. We discuss the extension to the N $$ \mathcal{N} $$ = 1 super JT model. On the disk, we similarly derive properties of the 1/C super-Schwarzian perturbation series, which we independently develop as well. As a byproduct, it is shown that JT supergravity saturates the chaos bound λ L = 2 π / β at first order in 1/C. We develop the fixed-length amplitudes of Liouville supergravity at the level of the disk partition function, the bulk one-point function and the boundary two-point functions. In particular we compute the minimal superstring fixed length boundary two-point functions, which limit to the super JT degenerate correlators. We give some comments on higher topology at the end. | Degenerate operators in JT and Liouville (super)gravity | 10.1007/JHEP04(2021)245 |
2021-04-26 | Transition to turbulence is an important phenomenon which has been studied extensively in literature both experimentally as well as numerically. Development of turbulence characteristics in the laminar separation bubble has been studied experimentally using hot wire anemometer and numerically for two Reynolds number using two transition models. Experimentally measured turbulence characteristics are compared with numerical results, and the performance of the transition models has been brought out. | Measurement of Turbulent Characteristics at Low Reynolds Number and Comparison with CFD for Eppler 387 | 10.1007/s40032-021-00698-4 |
2021-04-19 | Background Low temperature severely depresses the uptake, translocation from the root to the shoot, and metabolism of nitrate and ammonium in thermophilic plants such as cucumber ( Cucumis sativus ). Plant growth is inhibited accordingly. However, the availability of information on the effects of low temperature on nitrogen transport remains limited. Results Using non-invasive micro-test technology, the net nitrate (NO 3 − ) and ammonium (NH 4 + ) fluxes in the root hair zone and vascular bundles of the primary root, stem, petiole, midrib, lateral vein, and shoot tip of cucumber seedlings under normal temperature (NT; 26 °C) and low temperature (LT; 8 °C) treatment were analyzed. Under LT treatment, the net NO 3 − flux rate in the root hair zone and vascular bundles of cucumber seedlings decreased, whereas the net NH 4 + flux rate in vascular bundles of the midrib, lateral vein, and shoot tip increased. Accordingly, the relative expression of CsNRT1.4a in the petiole and midrib was down-regulated, whereas the expression of CsAMT1.2a – 1.2c in the midrib was up-regulated. The results of 15 N isotope tracing showed that NO 3 − -N and NH 4 + -N uptake of the seedlings under LT treatment decreased significantly compared with that under NT treatment, and the concentration and proportion of both NO 3 − -N and NH 4 + -N distributed in the shoot decreased. Under LT treatment, the actual nitrate reductase activity (NRA act ) in the root did not change significantly, whereas NRA act in the stem and petiole increased by 113.2 and 96.2%, respectively. Conclusions The higher net NH 4 + flux rate in leaves and young tissues may reflect the higher NRA act in the stem and petiole, which may result in a higher proportion of NO 3 − being reduced to NH 4 + during the upward transportation of NO 3 − . The results contribute to an improved understanding of the mechanism of changes in nitrate transportation in plants in response to low-temperature stress. | Adaptation of cucumber seedlings to low temperature stress by reducing nitrate to ammonium during it’s transportation | 10.1186/s12870-021-02918-6 |
2021-04-17 | In this study, dual-phase (DP, ferrite + martensite) microstructures were obtained by performing intercritical heat treatments (IHT) at 750 and 800 °C followed by quenching. Decreasing the IHT temperature from 800 to 750 °C leads to: (i) a decrease in the volume fraction of austenite (martensite after quenching) from 0.68 to 0.36; (ii) ~ 100 °C decrease in martensite start temperature (Ms), mainly due to the higher carbon content of austenite and its smaller grains at 750 °C; (iii) a reduction in the block size of martensite from 1.9 to 1.2 μm as measured by EBSD. Having a higher carbon content and a finer block size, the localized microhardness of martensite islands increases from 380 HV (800 °C) to 504 HV (750 °C). Moreover, despite the different volume fractions of martensite obtained in DP microstructures, the hardness of the steels remained unchanged by changing the IHT temperature (~ 234 to 238 HV). Applying lower IHT temperature (lower fraction of martensite), the impact energy even decreased from 12 to 9 J due to the brittleness of the martensite phase. The results of the tensile tests indicate that by increasing the IHT temperature, the yield and ultimate tensile strengths of the DP steel increase from 493 to 770 MPa, and from 908 to 1080 MPa, respectively, while the total elongation decreases from 9.8 to 4.5%. In contrast to the normalized sample, formation of martensite in the DP steels could eliminate the yield point phenomenon in the tensile curves, as it generates free dislocations in adjacent ferrite. | Low-carbon cast microalloyed steel intercritically heat-treated at different temperatures: microstructure and mechanical properties | 10.1007/s43452-021-00222-6 |
2021-04-16 | Background Bio-nanotechnology is considered as one of the low-cost approaches that have been utilized in production of nanomaterials. The current research aimed at investigating the influence of different types of Actinomycete strains on the final properties of silver nanoparticles (AgNPs) such as size, shape, polydispersity, and antibacterial properties. For this purpose, the following techniques were employed UV spectrophotometer, SDS-PAGE electrophoresis, TEM, FTIR, antibacterial agar diffusion test, and Zetasizer. Results It was found that among 34 Streptomyces isolates collected from the soil, Streptomyces spiralis and Streptomyces rochei were able to reduce silver nitrate into sliver nanoparticles. The diversity and molecular weights of extracellular proteins secreted by these stains were different as proved by SDS-PAGE technique. This consequently resulted in differences in polydispersity of AgNPs which indicate that the sizes of AgNPs were highly dependent on the amount, molecular sizes, and diversity of extracellular matrix proteins of the microorganism. Conclusion This article might give an insight about the importance of molecular sizes of biomacromolecules such as proteins on the physical properties of biogenic synthesized nanoparticles. | Actinomycete strain type determines the monodispersity and antibacterial properties of biogenically synthesized silver nanoparticles | 10.1186/s43141-021-00153-y |
2021-04-15 | Natural geochemical processes and anthropogenic activities produce selenium (Se)-containing wastewater, in which selenium is present as selenous acid (Se(IV)) and selenic acid (Se(VI)). Herein, we evaluated the Se removal performances of magnesium oxide (MgO) with different crystallinities at pH 10.5. Normal MgO and low-crystalline (LC-MgO) were reacted in 1, 2, and 5 mg dm −3 Se(IV) or Se(VI) solution for 120 min. The Se concentrations of both the species did not apparently decrease in the normal MgO systems. However, >90% of Se(IV) was successfully removed by LC-MgO within 5 min under all conditions. X-ray diffraction (XRD) analysis indicated that Se(IV) was removed via surface complexation on Mg(OH) 2 formed by the rapid hydration of LC-MgO. The enhancement of Se removability of the LC-MgO system was explained by the rapid hydration of the higher surface area of LC-MgO when compared with that of normal MgO. Majority of the Se(VI) (60–80%) was removed by LC-MgO during the first 20 min; however, it was gradually released back into the solution over time. During hydration, the changing XRD peak patterns and zeta potential of LC-MgO indicated that the increased charge density obtained by the accumulation of Mg 2+ released via MgO dissolution would cause the temporal uptake of Se(VI) in the interlayer of Mg(OH) 2 . Subsequently, the charge density decreased with the hydration of Mg 2+ , indicating that Se(VI) was redissolved. Therefore, LC-MgO is a promising material for treating Se-containing alkaline wastewater. However, short-time operation and low concentration (<1 mg dm −3 ) must be ensured for successful Se(VI) removal. | Selenite and Selenate Adsorption on Low-Crystalline Magnesium Oxide Under Alkaline Conditions | 10.1007/s11270-021-05127-x |
2021-04-15 | Efficient delivery of dry powder aerosols dispersed with low volumes of air is challenging. This study aims to develop an efficient dry powder inhaler (DPI) capable of delivering spray-dried Survanta-EEG powders (3–10 mg) with a low volume (3 mL) of dispersion air. A series of iterative design modifications were made to a base low air volume actuated DPI. The modifications included the replacement of the original capsule chamber with an integral dose containment chamber, alteration of the entrainment air flow path through the device (from single-sided (SS) to straight through (ST)), change in the number of air inlet holes (from one to three), varying the outlet delivery tube length (45, 55, and 90 mm) and internal diameter (0.60, 0.89, and 1.17 mm). The modified devices were evaluated by determining the influence of the modifications and powder fill mass on aerosol performance of spray-dried Survanta-EEG powders. The optimal DPI was also evaluated for its ability to aerosolize a micronized powder. The optimized dose containment unit DPI had a 0.21 mL powder chamber, ST airflow path, three-0.60 mm air inlet holes, and 90 mm outlet delivery tube with 0.89 mm internal diameter. The powder dispersion characteristics of the optimal device were independent of fill mass with good powder emptying in one 3 mL actuation. At 10 mg fill mass, this device had an emitted mass of 5.3 mg with an aerosol Dv50 of 2.7 μm. After three 3 mL actuations, >85% of the spray-dried powder was emitted from the device. The emitted mass of the optimal device with micronized albuterol sulfate was >72% of the nominal fill mass of 10 mg in one 3 mL actuation. Design optimization produced a DPI capable of efficient performance with a dispersion air volume of 3 mL to aerosolize Survanta-EEG powders. | Performance of Low Air Volume Dry Powder Inhalers (LV-DPI) when Aerosolizing Excipient Enhanced Growth (EEG) Surfactant Powder Formulations | 10.1208/s12249-021-01998-9 |
2021-04-10 | Poisonous gases, such as H 2 S and PH 3 , produced by industrial production harm humans and damage the environment. In this study, H 2 S and PH 3 were simultaneously removed at low temperature by modified activated carbon fiber (ACF) catalysts. We have considered the active metal type, content, precursor, calcination, and reaction temperature. Experimental results exhibited that ACF could best perform by loading 15% Cu from nitrate. The optimized calcination temperature and reaction temperature separately were 550°C and 90°C. Under these conditions, the most removal capacity could reach 69.7 mg/g and 132.1 mg/g, respectively. Characterization results showed that moderate calcination temperature (550°C) is suitable for the formation of the copper element on the surface of ACF, lower or higher temperature will generate more cuprous oxide. Although both can exhibit catalytic activity, the role of the copper element is significantly greater. Due to the exceptional dispersibility of copper (oxide), the ACF can still maintain the advantages of larger specific surface area and pore volume after loading copper, which is the main reason for better performance of related catalysts. Finally, increasing the copper loading amount can significantly increase the crystallinity and particle size of copper (oxide) on the ACF, thereby improving its catalytic performance. In situ IR found that the reason for the deactivation of the catalyst should be the accumulation of generated H 2 PO 4 and SO 4 2− (H 2 O) 6 which could poison the catalyst. | A Cu-modified active carbon fiber significantly promoted H2S and PH3 simultaneous removal at a low reaction temperature | 10.1007/s11783-021-1425-3 |
2021-04-08 | In recent years, the use of polyethylene (PE) for asphalt modification has been gaining increased attention due to the environmental sustainability and cost-saving benefits. To optimize the performance of the PE-asphalt blends, it is necessary to understand the polymer-binder interactions and their impact on the properties of the modified asphalt binder. In this study, low-density polyethylene (LDPE) with low and high melt flow index (MFI), i.e., LDPE4 and LDPE70, were blended with Pen 60-70 asphalt binder in dosages ranging from 1 to 5 wt.%. PE Wax was also added to the binder or the PE-binder blend to enhance dispersion. The dispersion of PE in the binder and the phase stability of the modified binder were investigated by optical microscope. The equivalent diameter of PE domains increased with time and the polymer dosage level. The addition of PE wax improved the polymer dispersity in the LDPE4 blends. The polymer dispersity in LDPE70 blends was good without adding PE Wax, attributed to the higher MFI value (low molecular weight) of LDPE70. In addition, to understand the stability of polymer modified binder, the steady shear viscosity-temperature profile of these binders was studied using a rotational viscometer. The dynamic rheological properties and performance of the PE-binder blends were evaluated using the dynamic shear rheometer. Based on the microstructure, all other rheological and performance properties, it was concluded that the 3% LDPE70 binder has better polymer dispersity, better low and high temperature performance characteristics. | Influence of polymer structure and amount on microstructure and properties of polyethylene-modified asphalt binders | 10.1617/s11527-021-01683-0 |
2021-04-08 | Field calibrations of NO 2 , NO, and PM 10 from AQMesh Air Quality Monitors (AQMs) were conducted during a summer and an autumn period in a busy street in a midsize Swedish city. All the three linear calibration procedures studied (postscaled, bisquare, and orthogonal data) significantly reduced the ranges and magnitudes of the performance indicators to yield more reliable results than the raw data. The improvements were sufficient to satisfy the European Union (EU) Data Quality Objective (DQO) for indicative measurements as compared to reference data only for NO 2 (above 50 µg m −3 ) and NO (above 30 µg m −3 ) during the autumn calibration period. The relatively simple bisquare procedure had the best performance overall. The bisquare procedure improved the root mean square error by the same amount as other studies using complex multivariate calibration methods. Low concentrations of pollutants were measured, far below the EU Environmental Quality Standard thresholds and even satisfying the future goals for the Environmental Quality Objectives. Cleaning the raw data by removing data points in the reference data that were below the reference station limit of detections (and the synchronous data points in the AQM prescaled data) was found to improve the performances of the calibration procedures appreciably. Many NO 2 and almost all PM 10 data points in this study fell below the AQM limit of detection. These low concentrations will probably be a common problem in many field studies, at least in areas with relatively low air pollution. However, the relative errors were sufficiently low for these data points that they could be interpreted as accurately representing low concentrations and did not need to be removed from the datasets. For the NO 2 measurements, a slight periodic error correlated with sunlight and increased ambient temperature was noted. NO measurements correlated strongly with increased traffic. | Evaluation of field calibration methods and performance of AQMesh, a low-cost air quality monitor | 10.1007/s10661-021-09033-x |
2021-04-08 | Methanotrophs (methane-oxidizing bacteria) can degrade methane into carbon dioxide and water. In this paper, several types of methanotrophs have been successfully cultivated and sorted out based on microbial technology, and the processes and approaches used are described in detail. By using several types of active methanotrophs, a few groups of experimental investigations have been carried out to determine their degradation effects on methane gas; these studies used different low methane concentrations that were less than 1.5%. The experimental results showed that the methanotrophs studied can still show the characteristics of normal activity under the conditions of a series of low methane concentrations that ranged from 0.25 to 1.5%. In the degradation process, with the increased methane concentrations in the mixed gas, more methane could ultimately be degraded to carbon dioxide. The decrease in methane and increase in carbon dioxide presented approximately linear relationships, and the numerical relationships between carbon dioxide and methane and the microbial degradation times could be described by exponential functions with high correlations. The conclusions in this paper attempt to forge a new path for the prevention of exceeding limited methane concentrations during coal mining by the use of microbial technology. | Experimental investigation of the use of methanotrophs for the degradation of low-concentration methane | 10.1007/s12517-021-07035-0 |
2021-04-06 | Background Magnetic resonance imaging (MRI) is uniquely suited to non-invasively and continuously monitor embolism formation in trees. Depending on the MRI method used, quantitative parameter maps of water content and MRI signal relaxation behavior can be generated. The ability to measure dynamic differences in water content and relaxation behavior can be used to detect xylem embolism formation, even if xylem conduits are too small to be spatially resolved. This is especially advantageous when using affordable small-scale low-field MRI scanners. The amount of signal that can be obtained from an object strongly depends on the strength of the magnetic field of the imager’s magnet. Imaging at lower resolutions thus would allow to reduce the cost, size and weight of the MRI scanner and to shorten image acquisition times. Results We investigated how much spatial resolution can be sacrificed without losing the ability to monitor embolism formation in coniferous softwood (spruce, Picea abies ) and diffuse porous beech ( Fagus sylvatica ). Saplings of both species were bench dehydrated, while they were continuously imaged at stepwise decreasing spatial resolutions. Imaging was done by means of a small-scale MRI device, utilizing image matrix sizes of 128 × 128, 64 × 64 and 32 × 32 pixels at a constant FOV of 19 and 23 mm, respectively. While images at the lowest resolutions (pixel sizes 0.59 × 0.59 mm and 0.72 × 0.72 mm) were no longer sufficient to resolve finer details of the stem anatomy, they did permit an approximate localization of embolism formation and the generation of accurate vulnerability curves. Conclusions When using MRI, spatial resolution can be sacrificed without losing the ability to visualize and quantify embolism formation. Imaging at lower spatial resolution to monitor embolism formation has two advantages. Firstly, the acquisition time per image can be reduced dramatically. This enables continuous imaging at high time resolution, which may be beneficial to monitor rapid dynamics of embolism formation. Secondly, if the requirements for spatial resolution are relaxed, much simpler MRI devices can be used. This has the potential to make non-invasive MR imaging of embolism formation much more affordable and more widely available. | Reduced spatial resolution MRI suffices to image and quantify drought induced embolism formation in trees | 10.1186/s13007-021-00732-7 |
2021-04-05 | The Pt-based expensive catalysts and sluggish kinetics at cathode in oxygen reduction reaction (ORR) hinder the rapid commercialization of fuel cells. The quest for cheap, non-noble metal catalysts to replace Pt-based catalysts has thus become a critical issue in the field of fuel cells. The carbon black (CB) and CB supported catalyst have been explored with the ultimate goal of finding a substitute for Pt-based catalysts in fuel cells. In the present work, we synthesized Zn-based MOF ( 1 ), 1 selectivity gives H 2 O 2 followed by two-electron pathways. However, sample 1 modification might be needed to enhance its selectivity for the generation of H 2 O. Two composites of MOFs with carbon black and 1 were prepared to increase the H 2 O yield, called 1⊃CB and 1⊃SCB . The electrochemical generation of H 2 O 2 was analyzed by the rotating ring disk electrode (RRDE) using catalyst 1 . Following the addition of CB, H 2 O 2 yields decreased from above 93% ( 1 ) to 59% and 75% for 1⊃CB and 1⊃SCB , respectively. CB modified catalysts moved towards four-electron pathways due to the conductive nature of CB. Electrochemical Impedance Spectroscopy (EIS) has also been performed to study in detail the conductivity effect of CB and kinetic behavior of ORR in alkaline electrolyte. This research opens up a new path for ORR to advance non-precious metal catalysts based on MOFs. Graphic abstract Synopsis : This paper describes how we synthesized carbon Black (CB) supported MOF: Zn-based MOF ( 1 ), 1 selectivity gives H 2 O 2 (two-electron pathways). Two composites of MOFs ( 1⊃CB and 1⊃SCB ) were prepared to increase the H 2 O yield. After addition of CB, H 2 O 2 yields decreased from above 93% (1) to 75% ( 1⊃SCB ) and 59% ( 1⊃CB ). | Metal-Organic Framework and Carbon Black supported MOFs as dynamic electrocatalyst for oxygen reduction reaction in an alkaline electrolyte | 10.1007/s12039-021-01900-x |
2021-04-05 | There is growing interest among nutritionists in feeding reduced protein diets to broiler chickens. Although nearly a century of research has been conducted providing biochemical insights on the impact of reduced protein diets for broilers, practical limitation still exists. The present review was written to provide insights on further reducing dietary protein in broilers. To construct this review, eighty-nine peer reviewed manuscripts in the area of amino acid nutrition in poultry were critiqued. Hence, nutritional research areas of low protein diets, threonine, glycine, valine, isoleucine, leucine, phenylalanine, histidine, and glutamine have been assessed and combined in this text, thus providing concepts into reduced protein diets for broilers. In addition, linkages between the cited work and least cost formation ingredient and nutrient matrix considerations are provided. In conclusion, practical applications in feeding reduced protein diets to broilers are advancing, but more work is warranted. | Progress of amino acid nutrition for diet protein reduction in poultry | 10.1186/s40104-021-00568-0 |
2021-04-01 | Product quality and efficiency are critical phenomena for every manufacturing unit to survive the pressure of the present days. This situation demands to develop a new cutting tool for industrial application. Hence, the current work aims to study the performance characteristics of the newly powder metallurgy (P/M) made Fe-1% C-1% W-1% Ti and Fe-1% C-2% W-1% Ti cutting tools under the turning of AISI 1020 low carbon steel and AA 6061 aluminum alloy through powder metallurgy (P/M) route. The working parameters such as cutting speed, feed rate and depth of cut were varied in the experiments as per Taguchi's L9 orthogonal array. With each set of experiments, the surface roughness, tool wear and tooltip temperature were measured as response parameters. The experiments were carried out on two different work materials (hard and soft) under the same cutting conditions. Response tables on means of responses and signal-to-noise ratios of responses were employed to analyze the experimental results and to determine the contribution of process parameters to the output characteristics. The experimental results reveal that cutting speed is ranked one in effecting the tooltip temperature, and feed rate is ranked one for effecting surface roughness. The P/M alloy tool with 2% W has a marginally better performance than a tool with 1% W due to the enhanced hardness of the tool from 65 HRC to 83 HRC by the addition of tungsten, which causes the formation of hard phases such as martensite and carbides in the alloy system. | Effects of Working Parameters on Performance Characteristics of Cutting Tools Processed through Powder Metallurgy under Turning Operation | 10.1007/s11665-021-05622-6 |
2021-04-01 | Pore structure characteristics are significant factor in the evaluation of the physical characteristics of low-rank coal. In this study, three low-rank coal samples were collected from the Xishanyao Formation, Santanghu Basin, and low-temperature liquid-nitrogen adsorption (LP-N 2 A) measurements were taken under various pretreatment temperatures. Owing to the continuous loss of water and volatile matter in low-rank coal, the total pore volume assumes a three-step profile with knee temperatures of 150 °C and 240 °C. However, the ash in the coal can protect the coal skeleton. Pore collapse mainly occurs for mesopores with aperture smaller than 20 nm. Mesopores with apertures smaller than 5 nm exhibit a continuous decrease in pore volume, whereas the pore volume of mesopores with apertures ranging from 5 to 10 nm increases at lower pretreatment temperatures (<150 °C) followed by a faint decrease. As for mesopores with apertures larger than 10 nm, the pore volume increases significantly when the pretreatment temperature reaches 300 °C. The pore structure of low-rank coal features a significant heating effect, the pretreatment temperature should not exceed 150 °C when the LP-N 2 A is used to evaluate the pore structure of low-rank coal to effectively evaluate the reservoir characteristics of low-rank coal. | The dynamic change of pore structure for low-rank coal under refined upgrading pretreatment temperatures | 10.1007/s12182-020-00536-9 |
2021-04-01 | The effects of magnetizer parameters on the temperature field of high-strength steel blanks are investigated through the combination of experiment and simulation. An electromagnetic-temperature three-dimensional finite element model is simulated. Numerical simulation indicates the spacing in the width direction significantly affects the temperature field of steel blanks, and the optimal spacing of magnetic ring group to generate a rectangular low-temperature zone is 10 mm. The customizability of district-controlled induction heating process is verified, and then, the differentiated temperature field of automobile B-pillar is tailored. The temperature field simulation results are validated through heating experiments. Hot stamping experiment shows that a reduced U-shape B-pillar with tailored properties is generated after district-controlled induction heating-hot stamping. The temperature fields of B-pillar with two dimensions indicate this new process satisfies the demand of automobile components with tailored properties, and the parameters of magnetizers play the most important role in the new process. | Effects of magnetizer parameters on the temperature field of high-strength steel blank in district-controlled induction heating-hot stamping | 10.1007/s00170-021-06806-z |
2021-04-01 | Two-dimensional (2D) materials, such as transition metal dichalcogenides (TMDs), black phosphorus (BP), MXene and borophene, have aroused extensive attention since the discovery of graphene in 2004. They have wide range of applications in many research fields, such as optoelectronic devices, energy storage, catalysis, owing to their striking physical and chemical properties. Among them, anisotropic 2D material is one kind of 2D materials that possess different properties along different directions caused by the intrinsic anisotropic atoms’ arrangement of the 2D materials, mainly including BP, borophene, low-symmetry TMDs (ReSe 2 and ReS 2 ) and group IV monochalcogenides (SnS, SnSe, GeS, and GeSe). Recently, a series of new devices has been fabricated based on these anisotropic 2D materials. In this review, we start from a brief introduction of the classifications, crystal structures, preparation techniques, stability, as well as the strategy to discriminate the anisotropic characteristics of 2D materials. Then, the recent advanced applications including electronic devices, optoelectronic devices, thermoelectric devices and nanomechanical devices based on the anisotropic 2D materials both in experiment and theory have been summarized. Finally, the current challenges and prospects in device designs, integration, mechanical analysis, and micro-/nano-fabrication techniques related to anisotropic 2D materials have been discussed. This review is aimed to give a generalized knowledge of anisotropic 2D materials and their current devices applications, and thus inspiring the exploration and development of other kinds of new anisotropic 2D materials and various novel device applications. | Recent advances in anisotropic two-dimensional materials and device applications | 10.1007/s12274-020-3018-z |
2021-04-01 | Abstract In this work, a multi-core–shell-structured LiFePO 4 @Na 3 V 2 (PO 4 ) 3 @C (LFP@NVP@C) composite was successfully designed and prepared to address inferior low-temperature performance of LiFePO 4 cathode for lithium-ion batteries. Transmission electron microscopy (TEM) confirms the inner NVP and outer carbon layers co-existed on the surface of LFP particle. When evaluated at low-temperature operation, LFP@NVP@C composite exhibits an evidently enhanced electrochemical performance in term of higher capacity and lower polarization, compared with LFP@C. Even at − 10 °C with 0.5C, LFP@NVP@C delivers a discharge capacity of ca. 96.9 mAh·g −1 and discharge voltage of ca. 3.3 V, which is attributed to the beneficial contribution of NVP coating. NASICON-structured NVP with an open framework for readily insertion/desertion of Li + will effectively reduce the polarization for the electrochemical reactions of the designed LFP@NVP@C composite. Graphic abstract | Multi-core–shell-structured LiFePO4@Na3V2(PO4)3@C composite for enhanced low-temperature performance of lithium-ion batteries | 10.1007/s12598-020-01669-x |
2021-04-01 | Low temperature in later spring severely limits plant growth and causes considerable yield loss in wheat. In this study, the impacts of exogenous salicylic acid (SA) on plant growth, grain yield and key physiological parameters of wheat plants were investigated under field low-temperature conditions using a field air temperature control system (FATC). The results showed that low-temperature stress significantly decreased leaf net photosynthetic rate, plant height and biomass production of wheat plants at the jointing stage, resulting in a reduction in grain yield. Moreover, the growth period of wheat plants was prolonged by low-temperature stress. However, SA-treated plants significantly improved the photochemical efficiency of photosystem II, accumulation of osmo-protectants, activities of enzymatic antioxidants, and pool of non-enzymatic low molecular substances compared with non-SA-treated plants under low-temperature stress. Pretreatment with SA effectively alleviated low-temperature-induced reduction in leaf net photosynthetic rate, plant height, biomass production and grain yield as well as prolonging of growth period of wheat plants. However, SA-treated plants had no significant effects on the expression levels of cold-responsive genes compared with non-SA-treated plants under low-temperature stress. Our results demonstrated that exogenous application of SA is an appropriate strategy for wheat to resist late spring low-temperature stress under field conditions. | Alleviation of Field Low-Temperature Stress in Winter Wheat by Exogenous Application of Salicylic Acid | 10.1007/s00344-020-10144-x |
2021-04-01 | Abstract A series of Mn–Ti oxide catalysts were synthesized by the sol–gel method and the effects of different synthesis conditions were investigated in sequence. The microstructures and properties of the catalysts were characterized by using N 2 adsorption–desorption, XRD, SEM, H 2 -TPR, NH 3 -TPD, Raman and XPS. The catalytic performance over Mn–Ti oxide catalysts prepared under different synthesis conditions for the low-temperature SCR of NO with NH 3 were also comparatively evaluated. The results reveal that the calcination temperature and metal source play a significant role in the characteristics and the SCR activities of the catalysts. A relatively low calcination temperature is beneficial to low-temperature SCR activity. Manganese nitrate or manganese acetate as the Mn source combining with tetrabutyl titanate as Ti source can achieve high SCR activities. The excellent low-temperature NH 3 -SCR activity can be ascribed to the appropriate textural properties, amorphous Mn-oxides with equal ratio of Mn 3+ /Mn 4+ , good low-temperature reducibility and abundant surface B-acid sites. Graphic Abstract | Low-Temperature Selective Catalytic Reduction of NO with NH3 Over Mn–Ti Oxide Catalyst: Effect of the Synthesis Conditions | 10.1007/s10562-020-03365-y |
2021-04-01 | Abstract The structure and mechanical properties of 09G2S steel are studied during uniaxial tension tests in the temperature range from room temperature to 1200°C. The temperatures above which the strength properties of the steel decrease are determined. Austenite grain growth is shown to be very weak in the temperature range from room temperature to 1000°C. | Effect of High Temperatures on the Mechanical Properties of 09G2S Steel | 10.1134/S003602952104025X |
2021-04-01 | In this work, a 90W-4.9Ni-2.1Fe-3Cu alloy was developed for low-temperature sintering. Conventional 90W-7Ni-3Fe alloy, which is typically manufactured at 1500 °C, was synthesized at the same sintering conditions for comparison. In the low-temperature range from 1250 to 1400 °C, sintering densification, microstructure evolution, and mechanical properties were systematically investigated. For the 90W-4.9Ni-2.1Fe-3Cu alloy, a rapid specimen densification occurs at 1350 °C due to liquid formation over the temperature range from 1328 to 1370 °C. The maximum relative density of 99.01% of the alloy is reached at 1400 °C. According to electron probe microanalysis (EPMA) and transmission electron microscopy (TEM), the alloy is composed of a W phase and a γ-(Ni, Fe, Cu) matrix phase, which is well bonded with W grains. The orientation relationship of these two phases can be described as [001] γ-(Ni, Fe, Cu) ∥[ $$\bar{1}$$ 1 ¯ 33] W . The tensile strength and hardness of the sintered alloy increase with increasing sintering temperature. At 1400 °C, the tensile strength of the 90W-4.9Ni-2.1Fe-3Cu alloy is with 874 MPa considerably higher than that of the 90W-7Ni-3Fe alloy (385 MPa). The formation mechanism of γ-(Ni, Fe, Cu) phase is included in the discussion. | Densification, Microstructure Evolution, and Mechanical Properties of Low-Temperature-Sintered 90W-4.9Ni-2.1Fe-3Cu Alloy | 10.1007/s11665-021-05539-0 |
2021-04-01 | By conducting tension–tension low-cycle fatigue tests on three groups of specimens, this paper determined the mechanism and effect of warm laser shock peening (WLSP) on the fatigue performance of DD6 nickel-based single-crystal superalloy. The WLSP treatment induced ripples at the specimen surface, residual stress fields, and dislocation structures in the near-surface layers. The induced ripples increased the surface roughness of the specimens, and the residual stress fields and dislocation structures improved their surface microhardness. Moreover, both the surface roughness and surface microhardness exhibited a tendency to increase with the increase in the WLSP treatment number. During the low-cycle fatigue tests, the specimens underwent plastic deformation, and the $$a/2\left\langle {110} \right\rangle \left\{ {111} \right\}$$ a / 2 110 111 slip system was activated. In addition, the WLSP-induced dislocation structures developed during the low-cycle fatigue tests produced dislocation networks and superlattice intrinsic stacking faults, both of which had a positive effect on prolonging the fatigue life of the material. Furthermore, the fatigue life of the material tended to increase with the increasing number of WLSP impacts. | Effect of Warm Laser Shock Peening on the Low-Cycle Fatigue Behavior of DD6 Nickel-Based Single-Crystal Superalloy | 10.1007/s11665-021-05508-7 |
2021-04-01 | A low MgO content in sinter is conducive to reduce the MgO content in blast furnace slag. This study investigated the effect of MgO content in sinter on the softening—melting behavior of the mixed burden based on fluxed pellets. When the MgO content increased from 1.31wt% to 1.55wt%, the melting temperature of sinter increased to 1521°C. Such an increase was due to the formation of the high-melting-point slag phase. The reduction degradation index of sinter with 1.31wt% MgO content was better than that of others. The initial softening temperature of the mixed burden increased from 1104 to 1126°C as MgO content in sinter increased from 1.31wt% to 1.55wt%, and the melting temperature decreased from 1494 to 1460°C. The permeability index ( S -value) of mixed burden decreased to 594.46 kPa·°C under a high MgO content with 1.55wt%, indicating that the permeability was improved. The slag phase composition of burden was mainly akermarite (Ca 2 MgSiO 7 ) when the MgO content in sinter was 1.55wt%. The melting point of akermarite is 1450°C, which is lower than other phases. | Softening—melting behavior of mixed burden based on low-magnesium sinter and fluxed pellets | 10.1007/s12613-020-2047-7 |
2021-04-01 | Key message Total of 14 SNPs associated with overwintering-related traits and 75 selective regions were detected. Important candidate genes were identified and a possible network of cold-stress responses in woody plants was proposed. Abstract Local adaptation to low temperature is essential for woody plants to against changeable climate and safely survive the winter. To uncover the specific molecular mechanism of low temperature adaptation in woody plants, we sequenced 134 core individuals selected from 494 paper mulberry ( Broussonetia papyrifera ), which naturally distributed in different climate zones and latitudes. The population structure analysis, PCA analysis and neighbor-joining tree analysis indicated that the individuals were classified into three clusters, which showed forceful geographic distribution patterns because of the adaptation to local climate. Using two overwintering phenotypic data collected at high latitudes of 40°N and one bioclimatic variable, genome–phenotype and genome–environment associations, and genome-wide scans were performed. We detected 75 selective regions which possibly undergone temperature selection and identified 14 trait-associated SNPs that corresponded to 16 candidate genes (including LRR-RLK, PP2A, BCS1, etc.). Meanwhile, low temperature adaptation was also supported by other three trait-associated SNPs which exhibiting significant differences in overwintering traits between alleles within three geographic groups. To sum up, a possible network of cold signal perception and responses in woody plants were proposed, including important genes that have been confirmed in previous studies while others could be key potential candidates of woody plants. Overall, our results highlighted the specific and complex molecular mechanism of low temperature adaptation and overwintering of woody plants. | Natural population re-sequencing detects the genetic basis of local adaptation to low temperature in a woody plant | 10.1007/s11103-020-01111-x |
2021-04-01 | An effective design strategy for preparing highly transparent polyimide film with low dielectric constant is presented. The key to the strategy is to simultaneously introduce meta -substituted structure and trifluoromethyl in polymer chains. By using this design strategy, a highly transparent polyimide film with low- k was synthesized from 3,5-diaminobenzotrifluoride ( m -TFPDA) and 4,4′-(hexafluoroisopropylidene) diphthalic anhydride (6FDA) through a two-step method. The obtained m -TFPDA/6FDA (CPI) film (∼30 µm) possesses high optical transparency (λ cutoff =334 nm, T 450nm =85.26%, Haze=0.31) and is close to colorless ( L *=96.03, a *=−0.34, b *=2.12, yellow index=3.96). The intrinsic k and dielectric loss value of the film are 2.27 and 0.0013 at 10 kHz, respectively. More importantly, such low dielectric performance could remain stable up to 280 °C, and the film shows a low moisture rate (∼0.51%), which helps to maintain the low- k property stability in different humid environments. Meanwhile, the film also shows good thermal stability and mechanical properties, with a glass transition temperature ( T g ) of 296 °C and the 5 wt% decomposition temperature ( T d,5% ) of 522 °C under N 2 . The tensile strength and tensile modulus of the film are 85.1 MPa and 1.96 GPa, respectively. In addition, the film is soluble in common solvents, which allows simple solution processing and low-cost, continuous roll-to-roll processes. This design strategy is beneficial to improving the transparency, lightening yellow color, lowering the dielectric constant and meanwhile maintaining the comprehensive properties of polyimide films, which is mainly due to the introduced meta -substituted and trifluoromethyl structures effectively inhibiting the transfer of charge transfer complex (CTC) effects and increasing the free volume of film. This design strategy could also be extended to other high-performance polymer systems. | Highly Transparent and Colorless Polyimide Film with Low Dielectric Constant by Introducing Meta-substituted Structure and Trifluoromethyl Groups | 10.1007/s10118-021-2514-2 |
2021-04-01 | Abstract The results of impact bending tests of 22K steel before and after long-term heat treatment provoking temper brittleness are presented, serial curves are plotted, the fracture surfaces after the tests are analyzed. The heat treatment of 22K steel, which provokes temper brittleness, is shown to cause a decrease in the ductile–brittle transition temperature by 30–40°C. | Effect of Long-Term Annealing on the Impact Toughness of 22K Steel | 10.1134/S0036029521040248 |
2021-04-01 | Mesostructured silica materials with surface area in the range of ~700–900 m 2 /g have been prepared using hydroxy-carboxylic acid compounds such as tartaric acid, malic acid and citric acid (low cost non-surfactant template/pore forming agents) and tetraethylorthosilicate (TEOS) as silica source by sol-gel reaction. The templates were removed by either soxhlet extraction or calcination method. Mesoporous carbon molecular sieves were then prepared by carbonizing sucrose inside the pores of the above prepared mesoporous silica using sulfuric acid as a catalyst. The materials were characterized by FTIR spectroscopy, powder X-ray diffraction (XRD), N 2 -sorption studies, microanalysis, thermal analysis and transmission electron microscopy (TEM). The resulting carbon material shows relatively higher surface area (~1100 m 2 /g), narrow pore size distribution and pore diameter of 4–5 nm. The mesoporosity of carbon material arises from interconnecting channels arrangements of mesoporous silica template. The mesoporous carbon material was used as a support for the immobilization of rhodium complex [HRhCO(TPPTS) 3 ] by ossification method. The prepared catalyst has been tested for the hydroformylation of higher olefins. The activity of the catalyst was improved by 20–30% as compared to the catalyst prepared from a conventional activated carbon support. | Synthesis, characterization and catalytic study of mesoporous carbon materials prepared via mesoporous silica using non-surfactant templating agents | 10.1007/s10934-020-01003-x |
2021-04-01 | The Fengyun series 4 (FY-4) Geostationary Interferometric Infrared Sounder (GIIRS) is the first interferometric infrared sounder operating in geostationary orbit internationally, for vertical air soundings of temperature and humidity. This paper describes the long-life Stirling cryocooler operating at 60 K in GIIRS. The cryocooler’s performance at room temperature, mounting status on the GIIRS, performance with and without phase control and on-orbit performance for 2 years are described. Until May 31, 2019, the cooler had more than 20,000 h of continuous running time with no indication of a change in performance. The undegraded performance provided by the cryocooler has enabled the GIIRS to fulfill its mission. | On-Orbit Performance of the FY-4 GIIRS Stirling Cryocooler Over 2 Years | 10.1007/s10909-021-02570-2 |
2021-04-01 | While the high elevation limit of trees is commonly related to low temperature, the rear edge of their distribution is often associated with drought. Here we explore phenology traits that contribute to a mechanistic explanation of both these edges of the fundamental niche in the broad leaved evergreen Quercus pannosa s.l. Populations of this species reach a drought limit (DL) at 2510 m in the semi-arid upper Yangtze valley, and a cold limit (CL) at 4270 m, very close to the conifer treeline, within a short geographical distance. Trees reach a height of only 4–7 m at both climatic limits, and > 30 m height at optimum site (OS) at 3440 m. At OS, flushing starts in mid-May and at the summer solstice at CL (after late frosts end), suggesting a photoperiod control. At DL, oak phenology tracks the (irregular) arrival of the monsoon. Shoots and leaves grew fastest and for the shortest period at DL, and slowest at CL, in both cases forming 4–7 cm long new shoots per year, contrasted by 12–13 cm a −1 at OS. Maturation of leaves (length and specific leaf area, SLA) was again fastest at DL, followed by CL and slowest at OS, with a much longer shoot growth duration per year and bigger leaves. We conclude that the period favorable for growth and maturation was more than halved at both range limits (by frost or drought) compared to the optimum site, pointing at a common range restriction by the duration of the growing season. | Elevation-specific responses of phenology in evergreen oaks from their low-dry to their extreme high-cold range limits in the SE Himalaya | 10.1007/s00035-020-00245-4 |
2021-04-01 | The microstructure–mechanical property relationship of a Cu-bearing low-carbon high-strength low-alloy steel, subjected to a novel multistage heat treatment including quenching (Q), lamellarization (L) and tempering (T), is presented. Yield strength of 989.5 MPa and average toughness at − 80 °C of 41 J were obtained in this steel after quenching and tempering (QT) heat treatments. Specimen QLT gained a little lower yield strength (982.5 MPa), but greatly enhanced average toughness at − 80 °C (137 J). To further clarify the strengthening and toughening mechanisms in specimen QLT, parameters of microstructural characteristic and crack propagation process were compared and analyzed for specimens Q, QL, QT and QLT. The microstructure of tempered martensite/bainite (M/B) in specimen QT changed to refined tempered M/B matrix mixed with minor IF (inter-critical ferrite) in specimen QLT. Cu-rich precipitates existed in tempered M/B for both specimens QT and QLT, as well as in IF. Compared with QT, adding a lamellarization step before tempering made the effective grains of specimen QLT refined and also led to coarser Cu-rich precipitates in tempered M/B matrix. The weaker strengthening effect of coarser Cu-rich precipitates should be a key reason for the slightly lower yield strength in specimen QLT than in specimen QT. No austenite was found in all specimens Q, QL, QT and QLT. Specimen QLT showed purely ductile fracture mode at − 80 °C due to the refined effective grains. The greatly improved toughness is mainly attributed to the enhanced energy of crack propagation. The combination of refined microstructure, softened matrix and deformation of minor ‘soft’ IF during crack propagation led to the most superior toughness of specimen QLT among all specimens. | Strengthening and toughening mechanism of a Cu-bearing high-strength low-alloy steel with refined tempered martensite/bainite (M/B) matrix and minor inter-critical ferrite | 10.1007/s42243-020-00500-2 |
2021-04-01 | HighSTEPS: A High Strain Temperature Pressure and Speed Apparatus to Study Earthquake Mechanics | 10.1007/s00603-021-02362-w | |
2021-04-01 | Abstract We report that the organic-inorganic composite of polyvinyl phenol (PVP) and lanthanum titanate can be used as a gate dielectric layer of a low-voltage thin film transistor (TFT). The high-k organic-inorganic composite is synthesized at low temperatures through a solution-processable method and deposited by a simple spin-coating technology on polyethylene terephthalate coated by indium tin oxide (PET-ITO) film substrate. The fabricated devices show small and positive threshold voltage, and thus are applicable for low-power and high-speed operation. Thin film organic-inorganic composite transistors show high current on/off on order of 10 4 , dependent on composition. Organic-inorganic thin film transistors (TFTs) fabricated using composite of polyvinyl phenol and lanthanum titanate layers as gate dielectric and zinc oxide (ZnO) films as channel layers exhibit superior electron transport characteristics with the electron mobility of 1.04 cm 2 V −1 s −1 , while the ratio of channel width ( W ) to channel length ( L ) for these devices is 20. Graphic Abstract | Solution-Processable LaTiOx-PVP as Silicon-Free Gate Dielectric at Low Temperature for High-Performance Organic-Inorganic Field Effect Transistors | 10.1007/s11664-021-08766-2 |
2021-04-01 | Low level radioactive liquid waste (LLW) is generated at different stages of operation of reprocessing as well as radioactive waste management. The LLW generated here is alkaline with high salt content. It contains different radioisotopes namely 106 Ru, 125 Sb, 99 Tc, 137 Cs, 90 Sr and traces of Pu. Presence of 99 Tc in LLW is of great environmental concern due to its long half-life (T 1/2 : 2 × 10 5 years) and mobility. Hence it needs to be separated from LLW to maximum possible extent prior to discharge to environment. In this paper, study carried out for separation of 99 Tc using the crown ether, Di-tert-Butyldibenzo-18-Crown-6 (DtBuDB18C6). The performance of the composite material was evaluated with respect to 99 Tc uptake and the effect of various parameters like pH, salt concentration, time period and temperature on K d value was studied. | Removal of 99Tc from low level radioactive liquid waste using di-tert-butyldibenzo-18-crown-6 impregnated sorbent | 10.1007/s10967-020-07553-3 |
2021-04-01 | The specimens of austenitic stainless steels were machined to different strain rates (105 s −1 , 1050 s −1 , 1500 s −1 , 2100 s −1 ). These specimens were subjected to low-temperature sensitization (LTS) heat treatment. The LTS treatment was carried out at 475℃ and 575℃ for 24 h. Further, oxalic acid, double-loop electrochemical potentiokinetic reactivation (DL-EPR) were carried out. As-machined specimens were subjected to surface roughness measurements, optical microscopy, electron backscattered diffraction (EBSD), and Fourier transform infrared spectroscopy (FTIR) imaging measurements. Machined specimen exhibited more difficulty in passivation than the as-received specimen. The complete surface statistics were extracted. The specimens machined at a strain rate of 2100 s −1 were exhibited a higher degree of sensitization (DoS) at LTS of 575℃ and 475℃ for 24 h, respectively, than other specimens. It was found that specimens machined at a higher strain rate produced smoother roughness. FTIR imaging was used to extract the signal intensity of chromium oxide (Cr 2 O3) peak. Detected Cr 2 O3 peak/signal was strong for the specimen that exhibited lower DoS as estimated from FTIR-imaging. | Studies of Low-Temperature Sensitization after Sub-Surface Damage Evolution in Austenitic Stainless Steel | 10.1007/s13632-021-00736-8 |
2021-04-01 | We explore the application of electropulsing for the control of phase transformation in a low-carbon steel. The effect of electropulsing on the transformation from austenite to ferrite in continuous casting low-carbon steel slab has been studied through experimental and thermodynamic investigations. The results reveal that electropulsing promotes the precipitation of ferrite within austenite grain in the low-carbon steel. When the electropulsing intensity increases, the precipitation of ferrite increases within austenite grains, and ferrite omentum precipitates become thinner along the austenite grain boundary. The results provide a basis for controlling the austenite to ferrite transformation in low-carbon steel. | Effect of electropulsing on austenite to ferrite transformation in low-carbon steel | 10.1007/s42243-021-00557-7 |
2021-04-01 | The effect of hot rolling process on microstructure evolution, mechanical properties and stress corrosion cracking (SCC) resistance of high-strength low-alloy (HSLA) steels was investigated by varying the finish rolling temperature (FRT) and total rolling reduction. The results revealed granular bainite with large equiaxed grains was obtained by a total rolling reduction of 60% with the FRT of 950 °C (within recrystallization temperature T r ). The larger grain size and much less grain boundaries should account for the relatively lower strength and SCC resistance. A larger rolling reduction of 80% under the same FRT resulted in the formation of massive martensite–austenite (M/A) constituents and resultant low ductility and SCC resistance. In contrast, a good combination of strength, ductility and SCC resistance was obtained via 80% rolling reduction with the FRT of 860 °C (within non-recrystallization temperature T nr ), probably because of the fine grain size and M/A constituents, as well as a high density of grain boundary network. | Simultaneously Improving Mechanical Properties and Stress Corrosion Cracking Resistance of High-Strength Low-Alloy Steel via Finish Rolling within Non-recrystallization Temperature | 10.1007/s40195-020-01161-6 |
2021-04-01 | The aim of this study was to form a low-carbon steel/TiN surface composite using duplex friction stir process (FSP) and plasma nitriding (PN). First, titanium powder was added to the steel surface by FSP through the pre-determined holes. After applying FSP, the specimens were subjected to plasma nitriding. The specimens were examined by optical and scanning electron microscopes, x-ray diffraction (XRD) analysis, microhardness test and pin-on-disk wear tests. Results of optical and scanning electron microscopy showed that the FSP process was successfully applied on the surface and modified the surface microstructure of the low-carbon steel. The surface hardness of the FSP sample increased by 42% over the hardness of the low-carbon steel and exhibited better wear resistance than the base metal. On the other hand, plasma nitriding also increased the surface hardness of the sample and the measured hardness was about 823 Vickers. This measured value was far greater than the 185 and 130 Vickers obtained for FSP steel and low-carbon steel, respectively. Due to the formation of TiN and the compound layer on the surface of the plasma nitriding sample, the highest wear resistance was obtained as compared with the other samples. For this sample, the wear mechanism was a combination of oxidation and adhesive. | Enhanced Surface Properties of Plain Carbon Steel by Duplex Process of Friction Stir Processing and Plasma Nitriding | 10.1007/s11665-021-05575-w |
2021-04-01 | This paper discusses the effect of thermal stress on the electrical properties, conduction and polarization, of low-voltage CSPE/XLPE-based power cables used in a nuclear power plant. The cables were subjected to an accelerated thermal stress at 120°C for an equivalent service period of 20, 40, 60 and 80 years. The capacitance, tan δ , resistivity at different frequencies and extended voltage response were the methods used for the investigation. A significant variation in the values of tan δ at low frequency, i.e., at 100 Hz, was observed. For the extended voltage response measurement, the decay voltage slope increased, showing the increase in the conduction particles inside the insulation material. While the decrease in return voltage slope showed that the slow polarization processes occurring at very low frequencies were decreased with aging. A strong correlation between the tan δ and decay voltage slope was also observed, which increased as the insulation aging increased. The results showed that the methods could be used for the in situ measurement of conduction and polarization phenomenon in the low-voltage cables, and hence helping in the assessment of the condition of cable insulation. | Dielectric loss and extended voltage response measurements for low-voltage power cables used in nuclear power plant: potential methods for aging detection due to thermal stress | 10.1007/s00202-020-01121-4 |
2021-04-01 | Interfacial properties govern the metallurgical and mechanical behaviour of welded specimens. Hence to study the effect of different parameters on weld interface is an important aspect to bring the desired output properties for various applications. In this study, a newly developed low velocity of detonation explosive welding (LVEW) process was applied to clad aluminium (Al) and low carbon steel (LCS) plates. Loading ratio (R) and stand-off distance (SD) were adopted for this study, as these two mostly affect the welding behaviour and act as important welding parameters. Microstructural examination as well as mechanical tests were performed. Three kinds of morphology were observed at the weld interface, i.e. large waves (LW), small irregular waves (SIW) and smooth flat interface (SFI), where SIW and SFI contribute interface devoid of voids, intermetallic and melting pockets. But at higher R and SD, AlFe and Al 2 Fe intermetallic were observed in non-continuous form in micron range. Elemental analysis confirmed the local diffusion with very thin diffusion thickness of 0.8–2 μm. Micro-hardness profile discloses the shock hardening effects across the vicinity of the weld interface, where an increase in hardness value was above the parent value. Chisel test and shear strength test also confirmed the good quality of bonding, while in shear fracture study, dimple structure was dominated in all the specimens. All these observations concluded that for cladding Al/LCS, LVEW process is best suitable and further, the practicability of these welded plates was checked by fabricating components like bi-metallic O-ring (push-fit type), hollow cylinder and bolts. | Effect of explosive welding parameters on Al/LCS interface cladded by low velocity of detonation explosive welding (LVEW) process | 10.1007/s00170-021-06800-5 |
2021-04-01 | The Shaxi porphyry Cu–Au deposit is located in the northern part of the Luzong Basin on the outer edge of the southern Middle-Lower Yangtze River metallogenic belt, China. It is typical of the porphyry Cu–Au deposits in the metallogenic belt, with more than 1 Mt Cu at 0.55 wt% and 45 tons Au at 0.47 g/t. Hydrothermal alteration consists of a core of potassic alteration overprinted by a phyllic alteration zone. Propylitic alteration occurs peripheral to the potassic zone, but can also be recognized in the core of the deposit, where vein density is low. The main mineralization occurs as sulfide veinlets in the potassic zone where it is superposed by phyllic alteration. The paragenetic sequence show that chalcopyrite began to precipitate late in stage 1, associated with potassic alteration, forming quartz-sulfide veins with potassium feldspar halos, and reached a peak in stage 3, forming chalcopyrite-pyrite ± quartz ± anhydrite ± chlorite ± illite veins that accompanied phyllic alteration. Sulfur, hydrogen-oxygen and strontium isotopes, fluid inclusions, and pyrite trace element data indicate that the stage 1 assemblage associated with potassic alteration were deposited from a magmatic brine. With the change from lithostatic to hydrostatic pressure late in stage 1, the brine generated stage 1 g quartz-pyrite-chalcopyrite ± anhydrite ± bornite ± molybdenite ± potassium feldspar veins with minor copper and gold. Mixing with minor external fluids (meteoric water or gypsum-saturated groundwater) in stage 2 triggered the peripheral propylitic alteration. As the proportion of external fluid increased with the onset of hydrostatic conditions, it changed the redox state and composition of the hydrothermal system, resulting in extensive stage 3 Cu and Au precipitation with phyllic alteration. Argillic alteration associated with stage 4 veins was generated by external fluids mixed with minor hydrothermal fluid, at shallow depths. | Ore genesis and hydrothermal evolution of the Shaxi porphyry Cu–Au deposit, Anhui province, Eastern China: evidence from isotopes (S–Sr–H–O), pyrite, and fluid inclusions | 10.1007/s00126-020-00995-5 |
2021-04-01 | Abstract The process parameters of the efficient influence on the block-like structuring of 10HFTBch low-perlite steel at thermoplastic treatment are identified. The thermoplastic treatment reserves ensuring high-level mechanical and technological properties of low-perlite steels are determined. | Reserves for Enhancing the Mechanical Performance of 10HFTBch Low-Perlite Steel Exposed to Thermoplastic Processing in Intercritical Temperature Ranges | 10.3103/S0967091221040100 |
2021-04-01 | The water-cooled WWR-K research reactor has been operating since 2016 using low-enrichment uranium fuel. In order to maintain high levels of generated power and reactivity margin sufficient for a 21-day operation cycle, the water-cooled core reflector of neutrons was gradually, depending on the fuel burnup, replaced by a beryllium one in order to prevent decreasing of the reactor performance. A series of calculation studies are performed with a simulation of the core region of the WWR-K reactor using an MCNP transport code including determination of neutron flux density, reactivity, efficiency of the control rods of the control and protection systems, as well as kinetic parameters critical for ensuring safe reactor operation. The calculated curves of the principal performance characteristics of the WWR-K reactor are presented and analyzed in terms of their use in scientific research and their effect on the reactor operation safety. | Time History of Performance Parameters of WWR-K Reactor during Gradual Replacement of the Water Reflector by a Beryllium One | 10.1007/s11182-021-02286-6 |
2021-04-01 | The low-dielectric inorganic adhesive is an important component of electromagnetic wave absorption coatings due to impedance matching with the atmospheric environment. Herein, high-enthalpy atmospheric plasma spraying (HE-APS) equipment is utilized to prepare Y 2 O 3 ceramic coatings, and the influence of spraying power on dielectric and physical properties of Y 2 O 3 ceramic coatings is systematically investigated. The surface and cross-sectional SEM images of Y 2 O 3 coating show that the overall coating morphology is smooth and less porous at high spraying power. This result is consistent with the trend of coating density and porosity. The XRD pattern demonstrates that the Y 2 O 3 coating possesses a stable cubic structure. The experimental results reveal that the dielectric properties of Y 2 O 3 coating are mainly affected by the porosity. According to the dielectric mixing rule of composite materials, Y 2 O 3 coating exhibits the minimum density of 4.86 g/cm 3 and permittivity of 9.70 under the spraying power of 55 kW. The current work highlights the feasibility of Y 2 O 3 as a low-dielectric inorganic adhesive in the field of electromagnetic wave applications. | Influence of High-Enthalpy Atmospheric Plasma Spraying Process Parameters on Microwave Dielectric Properties of Y2O3 Coatings | 10.1007/s11666-020-01144-0 |
2021-04-01 | Abstract Phase equilibria along sections of the potassium acetate–glycerol–water system at temperatures from 0 to –62°C were studied by visual-polythermal analysis. The potassium acetate to glycerol ratio in the sections studied varied from 3 : 1 to 1 : 3. Compositions forming low-temperature eutectics were found to be candidate new anti-icing reagents having good ice-melting ability. | Phase Equilibria along Sections of the Potassium Acetate–Glycerol–Water System at Temperatures from 0 to –62°C | 10.1134/S0036023621040112 |
2021-04-01 | There are four types of Mg–Al–Si–O inclusions observed in the Mg-treated Al-deoxidized ultra-low-carbon steel containing trace Si, including SiO 2 , 2MgO·SiO 2 , 3Al 2 O 3 ·2SiO 2 , and 2MgO·2Al 2 O 3 ·5SiO 2 and their composite inclusions. Using FactSage, the phase relationship of Mg–Al–Si–O system at 1473–2073 K was calculated using FactSage software, and the change in Si content can change the stable region range of different Mg–Al–Si–O-based inclusions. Based on the types of inclusions observed experimentally, the formation pathways of inclusions were predicted and a kinetic model was established to describe the formation process of the x MgO· y Al 2 O 3 –Mg–Al–Si–O and x Al 2 O 3 · y SiO 2 –Mg–Al–Si–O inclusions. | Effect of trace Si on MgO·Al2O3 inclusion in ultra-low-carbon steel | 10.1007/s42243-020-00529-3 |
2021-04-01 | A comparative study was performed to better understand the feasibility of osmotic distillation as a process to produce a low-alcohol beer. Four diverse commercial beers styles were considered. The regular and corresponding dealcoholised beers were compared. The quality attributes and the volatile compounds loss after the dealcoholisation were checked. The work focused on the sensory properties of the obtained samples. A trained panel evaluated how the chosen sensory descriptors were influenced by the treatment. The results of quality attributes and volatile compounds were in line with works previously published by the authors. Interestingly, the results highlighted that beer characterized by malty character is more suitable than pale lager to be dealcoholised by the osmotic distillation process. The low alcohol milk stout and stout flavour profile, especially in terms of taste, was like the corresponding regular beer. Osmotic distillation was demonstrated to be a feasible process to produce low-alcohol beer. | Influence of the dealcoholisation by osmotic distillation on the sensory properties of different beer types | 10.1007/s13197-020-04662-5 |
2021-04-01 | Dinoflagellates are frequently exposed to cold-water temperatures, and some may survive in winter and in polar regions. Cold shock domain proteins (CSPs) seem to function as part of their adaptation to such stressful environments. In this study, we identified two CSP genes ( PmCSP1 and PmCSP2 ) in the marine dinoflagellate Prorocentrum minimum , characterized their structural properties, and investigated their expression patterns in response to cold shock and heavy metal exposure. Putative PmCSP1 (96 aa, 10.1 kDa) and PmCSP2 (91 aa, 9.4 kDa) proteins had two consensus RNA-binding motifs and might be localized in the cytoplasm, due to the absence of a signal peptide. Phylogenetic analyses revealed that PmCSPs clustered with those of other dinoflagellates and had been recycled between genomic DNA and mRNA. Real-time PCR revealed that PmCSPs significantly responded to low temperatures, but not to nickel or cadmium. These genes may allow the organism to adapt to and survive in cold habitats and winter. | Transcriptomic identification and expression analysis of cold shock domain protein (CSP) genes in the marine dinoflagellate Prorocentrum minimum | 10.1007/s10811-020-02332-9 |
2021-04-01 | Key message Studied organic molecules in Pinus sylvestris L. seem to have acted as a safety net for metal transport, chelation and sequestration, allowing adaptation and growth under highly polluted conditions. Abstract Pinus sylvestris L. is known for its ability to survive in areas of highly elevated metal pollution, such as flotation tailings. The aim of the study was to estimate the content of selected organic molecules (including aliphatic low molecular weight organic acids (ALMWOAs), phenolic compounds and terpenes) and the physiological mechanisms underlying differences in metal/metalloid tolerance of P. sylvestris growing in unpolluted (soil) and polluted (flotation tailings) areas. The dominant ALMWOAs in rhizosphere soil extracts were citric acid followed by malic and oxalic acids, whereas in flotation tailings malic and oxalic acids. In roots and needles, the content of ALMOWAs was significantly higher in P. sylvestris L. tissue from flotation tailings in comparison to soil. Phenolic compounds were detected only in roots and needles, with a generally higher content of nearly all detected compounds from flotation tailings. The composition of roots did not contain all the compounds detected in needles. The profile of needles additionally contained four hydroxybenzoic, protocatechuic and salicylic acids. In pine needles, 24 volatile terpenes were identified in total. The content of these compounds in pine needles from the polluted area was markedly different from the unpolluted area. The dominant volatile monoterpenes in P. sylvestris L. needles from the unpolluted area was three carene, while in pine needles from the polluted area monoterpenes α-pinene was dominant. | The influence of environmental condition on the creation of organic compounds in Pinus sylvestris L. rhizosphere, roots and needles | 10.1007/s00468-020-02046-y |
2021-04-01 | The change of the electrical properties of amorphous SiInZnO thin-film transistors (SIZO TFTs) depending on Si concentration have been investigated. As the Si content increased from 1 to 3 wt%, the electrical properties are systematically degraded, such as field-effect mobility from 19.86 to 11.16 cm 2 V −1 s −1 . This change in properties has been found to deteriorate the SIZO network when Si content is highly added. In order to analyze the change of the electrical properties of SIZO depending on Si concentration, low frequency noise method and X-ray photoelectron spectroscopy analysis are adopted to investigate trap states in energy bandgap and oxygen vacancies of SIZO system. As a result, it was found that doping with a large amount of Si destabilizes the SIZO network, resulting in degrading electrical properties. | Effect of Silicon Doping on the Electrical Performance of Amorphous SiInZnO Thin-film Transistors | 10.1007/s42341-021-00285-5 |
2021-04-01 | The Choco low-level jet is among the main regional circulation mechanisms related to the advection of water vapor from the eastern Pacific to northwestern South America. Variations in the intensity of position of the jet core are identified as determinant for regional moisture transport and associated rainfall. This paper analyzes the annual cycle of intensity and latitudinal location of this jet according to different reanalysis and observational datasets. Moreover, we compare possible changes in the Choco jet occurred during past climates, like the little ice age (LIA), with those associated with future scenarios of greenhouse gas concentrations (RCP8.5), using simulations from the Paleoclimate Modelling Intercomparison Project Phase 3 (PMIP3) and the Coupled Model Intercomparison Project Phase 5 (CMIP5). Our results suggest that according to reanalysis/observational data, as well as the CMIP5 models with the best representation of the Choco jet in present climate, there is a positive correlation between the jet intensity and its latitudinal location, and such relationship is associated with the sea level pressure (SLP) difference between the eastern tropical Pacific and the northwestern South American landmass. Hence, stronger (weaker) SLP differences favor a stronger (weaker) intensity and a northward (southward) location of the Choco jet. PMIP3 simulations suggest a stronger and northward Choco jet during LIA due to a stronger SLP difference in comparison to present climate. However, under the RCP8.5 scenario, there is not robust agreement among CMIP5 models although the best models suggest a southward jet at the end of the 21st century. This suggests that the mechanisms influencing the Choco jet may play different roles during past natural climate changes with respect to anthropogenically-forced climate changes. | The Choco low‐level jet: past, present and future | 10.1007/s00382-020-05611-w |
2021-04-01 | Polyethylene has considered as non-degradable for decades, and their degradation through marine bacteria has rarely studied. However, LDPE found a significant source of pollution in the marine environment. In the present study, four bacterial strains capable of biodegradation of LDPE were isolated from the marine environment. These bacterial isolates H-237, H-255, H-256 and H-265 were revealed close similarity with Cobetia sp ., Halomonas sp ., Exigobacterium sp . and Alcanivorax sp., respectively based on 16S rRNA gene sequencing method. These bacterial isolates were individually incubated for 90 days supplied with LDPE films as a carbon source using the Bushnell-Haas medium. During the biodegradation assay, bacterial isolates were formed the viable biofilm on the LDPE surface, which decreased the thermal stability of the films. At the end of the incubation study, a maximum weight loss of 1.72% of LDPE film was observed by the bacterial isolate H-255. The bacterial attachment on the film changed the physical structure (surface erosion, roughness and degradation) which were confirmed by field emission scanning electron microscopy and atomic force microscopy. The changes in the chemical structure of the LDPE film were analyzed by Attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR). This ATR-FTIR showed the shifting of peaks of C–H stretch and C=C bond stretching and the new peaks formation of C–O and –C=C– bonds in comparison to control LDPE film. Further, biodegradation of LDPE film was also confirmed by remineralization of carbon and enzymatic activities. This study revealed that the active biodegradation of LDPE film by marine bacteria and these bacteria could reduce plastic pollution in the marine environment. | Marine bacterial biodegradation of low-density polyethylene (LDPE) plastic | 10.1007/s10532-021-09927-0 |
2021-04-01 | Mid-Infrared imaging is vital for the study of a wide variety of astronomical phenomena, including evolved stars, exoplanets, and dust enshrouded processes such as star formation in galaxies. However, infrared detectors have traditionally been expensive and it is difficult to achieve the sensitivity needed to see beyond the overwhelming mid-infrared background. Here we describe the upgrade and commissioning of a simple prototype, low-cost 10 μ m imaging instrument. The system was built using commercially available components including an uncooled microbolometer focal plane array and chopping system. The system was deployed for a week on the 1.52 m Carlos Sanchez Telescope and used to observe several very bright mid-infrared sources with catalogue fluxes down to ∼ 600 $\sim 600$ Jy. We report a sensitivity improvement of ∼ 4 $\sim 4$ mag over our previous unchopped observations, in line with our earlier predictions. | A low-cost chopping system and uncooled microbolometer array for ground-based astronomy | 10.1007/s10686-021-09744-6 |
2021-04-01 | We report the development of zeolite nanocapsules (MCM-22 and ZSM-5) encapsulating ultra-low amount (0.01 wt%) of noble metal nanoparticles (Gold, Platinum and Palladium) for the oxidation of HMF. These catalysts showed enhanced HMF conversion (> 95%) with higher yield (> 90%) of FDCA under mild conditions (60 °C, 0.3 MPa oxygen) in an organic solvent-free medium in 6 h. We also investigated the effect of size and amount of gold nanoparticles encapsulated inside zeolite capsules for the oxidation of HMF. We found that Au cluster loaded MCM-22 showed enhanced HMF conversion and yield of FDCA (91%). Graphic Abstract | Hollow Zeolites Encapsulating Ultra-Low Noble Metal Nanoparticles for HMF Oxidation | 10.1007/s10562-020-03361-2 |
2021-04-01 | The effects of inclusions on localized corrosion of Zr–Ti deoxidized low-alloy steels in marine environment were investigated by various analytical techniques including scanning electron microscopy with X-ray microanalysis (SEM/EDS), confocal Raman microscopy (CRM), and in situ scanning vibrating electrode technique (SVET). It was found that complex (Zr, Ti, Al)-O x inclusions were responsible for the initiation of localized corrosion. Localized corrosion preferentially occurred at Fe matrix adjacent to these inclusions and formed micro-gaps. In the early stage of corrosion, catalytic-occluded cells and the diffusion of chloride ions played a major role in the propagation of corrosion, further accelerating the dissolution of Fe matrix and (Zr, Ti, Al)-O x inclusions. Combining SVET and CRM results, it revealed that the maximum anodic current density in local area gradually decreased with prolonged exposure time, indicating that corrosion products covered the steel surface and lowered the propagation rate of corrosion. In the later stage of corrosion, the barrier effect of corrosion products played an important role in inhibiting localized corrosion. | Initiation and propagation of localized corrosion induced by (Zr, Ti, Al)-Ox inclusions in low-alloy steels in marine environment | 10.1007/s42243-020-00492-z |
2021-04-01 | We here characterize the response to the extremely low-frequency (ELF) magnetic field (MF, 50 Hz, 1 mT) of SH-SY5Y human neuroblastoma cells, cultured in a three-dimensional (3D) Alvetex ® scaffold compared to conventional two-dimensional (2D) monolayers. We proved that the growing phenotype of proliferating SH-SY5Y cells is not affected by the culturing conditions, as morphology, cell cycle distribution, proliferation/differentiation gene expression of 3D-cultures overlap what reported in 2D plates. In response to 72-h exposure to 50-Hz MF, we demonstrated that no proliferation change and apoptosis activation occur in both 2D and 3D cultures. Consistently, no modulation of Ki67 , MYCN , CCDN1 , and Nestin, of invasiveness and neo-angiogenesis-controlling genes ( HIF-1α , VEGF , and PDGF ) and of microRNA epigenetic signature (miR-21-5p, miR-222-3p and miR-133b) is driven by ELF exposure. Conversely, intracellular glutathione content and SOD1 expression are exclusively impaired in 3D-culture cells in response to the MF, whereas no change of such redox modulators is observed in SH-SY5Y cells if grown on 2D monolayers. Moreover, ELF-MF synergizes with the differentiating agents to stimulate neuroblastoma differentiation into a dopaminergic (DA) phenotype in the 3D-scaffold culture only, as growth arrest and induction of p21 , TH , DAT , and GAP43 are reported in ELF-exposed SH-SY5Y cells exclusively if grown on 3D scaffolds. As overall, our findings prove that 3D culture is a more reliable experimental model for studying SH-SY5Y response to ELF-MF if compared to 2D conventional monolayer, and put the bases for promoting 3D systems in future studies addressing the interaction between electromagnetic fields and biological systems. | Exposure of the SH-SY5Y Human Neuroblastoma Cells to 50-Hz Magnetic Field: Comparison Between Two-Dimensional (2D) and Three-Dimensional (3D) In Vitro Cultures | 10.1007/s12035-020-02192-x |
2021-04-01 | Steatosis is a liver lesion reported with numerous pharmaceuticals. Prior studies showed that severe impairment of mitochondrial fatty acid oxidation (mtFAO) constantly leads to lipid accretion in liver. However, much less is known about the mechanism(s) of drug-induced steatosis in the absence of severe mitochondrial dysfunction, although previous studies suggested the involvement of mild-to-moderate inhibition of mtFAO, increased de novo lipogenesis (DNL), and impairment of very low-density lipoprotein (VLDL) secretion. The objective of our study, mainly carried out in human hepatoma HepaRG cells, was to investigate these 3 mechanisms with 12 drugs able to induce steatosis in human: amiodarone (AMIO, used as positive control), allopurinol (ALLO), d -penicillamine (DPEN), 5-fluorouracil (5FU), indinavir (INDI), indomethacin (INDO), methimazole (METHI), methotrexate (METHO), nifedipine (NIF), rifampicin (RIF), sulindac (SUL), and troglitazone (TRO). Hepatic cells were exposed to drugs for 4 days with concentrations decreasing ATP level by less than 30% as compared to control and not exceeding 100 × C max . Among the 12 drugs, AMIO, ALLO, 5FU, INDI, INDO, METHO, RIF, SUL, and TRO induced steatosis in HepaRG cells. AMIO, INDO, and RIF decreased mtFAO. AMIO, INDO, and SUL enhanced DNL. ALLO, 5FU, INDI, INDO, SUL, RIF, and TRO impaired VLDL secretion. These seven drugs reduced the mRNA level of genes playing a major role in VLDL assembly and also induced endoplasmic reticulum (ER) stress. Thus, in the absence of severe mitochondrial dysfunction, drug-induced steatosis can be triggered by different mechanisms, although impairment of VLDL secretion seems more frequently involved, possibly as a consequence of ER stress. | Drug-induced hepatic steatosis in absence of severe mitochondrial dysfunction in HepaRG cells: proof of multiple mechanism-based toxicity | 10.1007/s10565-020-09537-1 |
2021-04-01 | Abstract The possibility of improving the thermal impact resistance and dielectric performance at 100–125°C of epoxy diane resins cured with an anhydride curing agent by means of reactive plasticizers (flexibilizers) and hardeners is considered. The efficiency of using CKD-KTRA low-molecular carboxylate rubbers as flexibilizers is confirmed, as well as the efficiency of using the condensation product of monoglycidyl ether and diethyl amine with oleic and sebacic acids as a hardener. It is shown that diglycidyl ether based on tribromaniline reduces combustibility. | Epoxy Anhydride Low-Combustibility Compositions for Impregnating Electronics Products | 10.1134/S1995421221020337 |
2021-04-01 | Abstract The paper investigates the mechanical and physical properties of low-carbon pipe steel (analog of steel 20 corresponding to TU-28-FR-73) after 39 years of service life in a crude gas pipeline at the Orenburg oil and gas condensate field. It is shown that the standard mechanical properties of the gas pipeline steel after long-term operation correspond to the TU-28-FR-73 standard. The effect of preliminary cyclic loading on the residual tensile strength of steel, the acoustic emission characteristics, and the residual magnetic field intensity estimated by the metal magnetic memory method is studied. After preliminary cycling, the steel was hardened and the acoustic regime changed due to damage accumulation. Four stages of damage evolution in the tensile steel are identified both before and after preliminary cyclic loading, and informative diagnostic criteria for the stages are proposed. Relationships are derived to relate the relative number of preloading cycles with the cumulative acoustic count, acoustic activity, slope of cumulative count-strain curves, acoustic gap duration, and residual magnetic field intensity. The listed characteristics are shown to be promising as diagnostic criteria for the state of the material. | Fracture Stages and Residual Strength of Pipe Steel after Long-Term Operation | 10.1134/S1029959921040123 |
2021-04-01 | Climate change has taken an increasingly important space in the development agenda. However, whether most countries can meet the challenge of mitigating climate change while simultaneously ensuring growth and poverty reduction remains debatable. This research contributes to the growing literature at the intersection of environment sustainability and economic/industrial development by identifying three dimensions of Green Industrial Policy (GIP), which rely on different approaches to mitigate climate change. Those three dimensions are (i) the consumption-centred dimension; (ii) the firm-level sustainability dimension, and (iii) the productionist innovation-driven dimension. This paper then applies this green industrial policy framework and examines the implications of pursuing different levels of GIP by drawing on a country case study (Ecuador). Two main findings arise from this study. First, a greener consumption is necessary but can hardly be achieved without industrial policies to stimulate green manufacturing and low-carbon innovation. Green industrial policy, therefore, has a central role to play in the structural transformation towards a low-carbon future. Second, a holistic and complementary approach is needed across the three dimensions of green industrial policy to ensure a coherent and developmental transition towards a low-carbon economy. Le changement climatique occupe une place de plus en plus importante dans le programme du développement international. Cependant, la plupart des pays peuvent-ils relever le défi de l'atténuation du changement climatique tout en assurant simultanément la croissance et la réduction de la pauvreté? Cela reste discutable. Cette étude contribue à la littérature croissante et se situe au croisement entre durabilité environnementale et du développement économique / industriel en identifiant trois dimensions de la politique industrielle écologique (PIE), qui reposent sur différentes approches pour atténuer le changement climatique. Ces trois dimensions sont: (i) la dimension centrée sur la consommation; (ii) la dimension de durabilité au niveau de l'entreprise, (iii) la dimension productiviste axée sur l'innovation. Cet article applique ensuite ce cadre de politique industrielle écologique et examine quelles sont les implications de la poursuite de différents niveaux de cette politique en s'appuyant sur l’étude de cas d’un pays (l’Équateur). Deux résultats principaux ressortent de cette étude. Premièrement, une consommation plus verte est nécessaire mais il est difficile d’atteindre ce but sans des politiques industrielles visant à stimuler la fabrication écologique et l'innovation à faible émission de carbone. La politique industrielle écologique a donc un rôle central à jouer dans la transformation structurelle vers un avenir sobre en carbone. Deuxièmement, il faut adopter une approche holistique et complémentaire dans les trois dimensions de la politique industrielle écologique pour assurer une transition cohérente et évolutive vers une économie sobre en carbone. | Three Dimensions of Green Industrial Policy in the Context of Climate Change and Sustainable Development | 10.1057/s41287-021-00365-5 |
2021-04-01 | Metallothioneins (MTs) are phylogenetically old cysteine-rich proteins, which are implicated in a variety of physiological and pathological processes. Their growth-regulating, anti-apoptotic and anti-inflammatory functions have been attributed not only to intracellular free radical scavenging and to zinc and copper regulation but also to the ability of secreted MT to bind on surface lipoprotein receptor-megalin/LRP2, which enables the endocytosis of MT-I/II and a wide range of other functionally distinct ligands. In the present study, we analysed the expression pattern of both proteins in 55 cases of premalignant transformation of cervical squamous cells, i.e. in low- and high-grade squamous intraepithelial lesion (LSIL and HSIL). The data showed that in LSIL (cervical intraepithelial neoplasia CIN1; N = 25) MTs were present only in basal and parabasal cells and that megalin was only weakly expressed. In HSIL (CIN2; N = 15 and CIN 3/carcinoma in situ; N = 15), however, overexpression and co-localization of MT with megalin were found in the entire hyperplastic epithelium. Moreover, megalin immunoreactivity appeared on the glandular epithelium and vascular endothelium, as well as on lymphatic cells in stroma. Besides, multiple megalin-positive cells expressed phosphorylated Akt1, implying that MT- and/or megalin-dependent prosurvival signal transduction pathways might contribute to the development of severe cervical dysplasia. The data emphasize the diagnostic power of combined MT/megalin analysis in pre-cancer screening. | Expression profiles of metallothionein-I/II and megalin/LRP-2 in uterine cervical squamous lesions | 10.1007/s00428-020-02947-w |
2021-04-01 | Background Progress has been made in the reduction of under-five mortality in India; however, neonatal mortality is reducing at a slower rate. Efforts are required to bring down neonatal mortality in order to attain the Sustainable Development Goal-3. Prevention of sepsis among the high-risk, vulnerable low birth weight neonates by a newer intervention with probiotic supplementation is promising. Methods A phase III, multicenter, randomized, double-blind, placebo-controlled study is being conducted at six sites in India. A total of 6144 healthy low birth weight (LBW) infants fulfilling the eligibility criteria would be enrolled within the first week of life, after obtaining written informed consent from the parents of the infant. Randomization in 1:1 ratio, stratified by site, sex, and birth weight, would be done through an interactive web response system (IWRS) using a standard web browser and email service. Vivomixx®, a probiotic containing a mix of 8 strains of bacteria, in a suspension form standardized to deliver 10 billion CFU/ml, or an organoleptically similar placebo would be fed to enrolled infants in a 1-ml/day dose for 30 days. The follow-up of enrolled infants for 60 days would take place as per a pre-specified schedule for recording morbidities and outcome assessments at the six participating sites. Screening for morbidities would be conducted by trained field workers in the community, and sick infants would be referred to designated clinics/hospitals. A physician would examine the referred infants presenting with complaints and clinical signs, and blood samples would be collected from sick infants for diagnosis of neonatal sepsis by performing sepsis screen and blood culture. Appropriate treatment would be provided as per hospital protocol. The study would be implemented as per the MRC guideline for the management of Global Health Trials in accordance with ICH-GCP and Indian Regulatory guidelines. A contract research organization would be engaged for comprehensive monitoring and quality assurance. The final analysis would be conducted in a blinded manner as per the statistical analysis plan (SAP) to estimate the primary outcomes of sepsis, possible serious bacterial infection (PSBI), and secondary outcomes. The codes will be broken after DMC permission. The protocol has been reviewed by the Research Ethics Committee of the Liverpool School of Tropical Medicine (REC-LSTM), from Research Ethics Committees of the six subject recruitment participating sites. Discussion This adequately powered and well-designed trial would conclusively answer the question whether probiotics can prevent neonatal sepsis in the high-risk group of low birth weight infants as indicated by a pilot study in 1340 LBW infants, evidence from systematic reviews of hospital-based studies, and a primary study on healthy newborns in Orissa. Results of the study would be generalizable to India and other low–middle-income countries. Trial registration Clinical Trial Registry of India (CTRI) CTRI/2019/05/019197 . Registered on 16 May 2019 | Evaluating the efficacy of a multistrain probiotic supplementation for prevention of neonatal sepsis in 0–2-month-old low birth weight infants in India—the “ProSPoNS” Study protocol for a phase III, multicentric, randomized, double-blind, placebo-controlled trial | 10.1186/s13063-021-05193-w |
2021-04-01 | The study tries to discover the impact of financial and social indicators’ growth towards environmental considerations to understand the drivers of economic growth and carbon dioxide emissions change in G7 countries. The DEA-like composite index has been used to examine the tradeoff between financial and social indicator matters in environmental consideration by using a multi-objective goal programming approach. The data from 2008 to 2018 is collected from G-7 countries. The results from the DEA-like composite index reveals that there is a mixed condition of environmental sustainability in G-7 countries where the USA is performing better and Japan is performing worse among the set of other countries. The further result shows that the energy and fiscal indicators help to decrease the dangerous gas emissions. Divergent to that, the human and financial index positively contributes to greenhouse gas emissions. Fostering sustainable development is essential to successfully reduce emissions, meet established objectives, and ensure steady development. The study provides valuable information for policymakers. | Does tradeoff between financial and social indicators matters in environmental consideration: evidence from G7 region | 10.1007/s11356-020-12041-y |
2021-04-01 | Background Low T3 syndrome is frequent in patients admitted to intensive care units for critical illness and pneumonia. It has been reported also in patients with COVID-19, Hodgkin disease and chronic lymphocytic leukemia. We analyzed the clinical relevance of Low T3 syndrome in COVID-19 patients and, in particular, in those with associated hematological malignancies. Methods Sixty-two consecutive patients, hospitalized during the first wave of SARS-CoV-2 outbreak in Sant’Andrea University Hospital in Rome, were subdivided in 38 patients (Group A), showing low levels of FT3, and in 24 patients (Group B), with normal FT3 serum values. During the acute phase of the disease, we measured serum, radiologic and clinical disease severity markers and scores, in search of possible correlations with FT3 serum values. In addition, in 6 COVID-19 patients, 4 with Low T3 syndrome, including 2 with a hematological malignancy, and 2 with normal FT3 values, we performed, high-dimensional single-cell analysis by mass cytometry, multiplex cytokine assay and gene expression profiling in peripheral blood mononuclear cells (PBMC). Results Low FT3 serum values were correlated with increased Absolute Neutrophil Count, NLR and dNLR ratios and with reduced total count of CD3+, CD4+ and CD8+ T cells. Low FT3 values correlated also with increased levels of inflammation, tissue damage and coagulation serum markers as well as with SOFA, LIPI and TSS scores. The CyTOF analysis demonstrated reduction of the effector memory and terminal effector subtypes of the CD4+ T lymphocytes. Multiplex cytokine assay indicates that mainly IL-6, IP-10 and MCAF changes are associated with FT3 serum levels, particularly in patients with coexistent hematological malignancies. Gene expression analysis using Nanostring identified four genes differently expressed involved in host immune response, namely CD38, CD79B, IFIT3 and NLRP3. Conclusions Our study demonstrates that low FT3 serum levels are associated with severe COVID-19. Our multi-omics approach suggests that T3 is involved in the immune response in COVID-19 and coexistent hematological malignancy and new possible T3 target genes in these patients have been identified. | Gene signature and immune cell profiling by high-dimensional, single-cell analysis in COVID-19 patients, presenting Low T3 syndrome and coexistent hematological malignancies | 10.1186/s12967-021-02805-6 |
2021-04-01 | The purposes of this study are to evaluate the effects of photobiomodulation (PBM) with laser and LED on rat calvaria osteoblasts (rGO lineage), cultured in osteogenic (OST) or regular (REG) medium, after induction of a quiescent state and to test if PBM is capable of osteogenic induction and if there is a sum of effects when combining OST medium with PBM. Before irradiation, the cells were put in a quiescent state (1% FBS) 24 h, when red (AlGaInP—660 nm) and infrared laser (GaAlAs—808 nm) and LED (637 ± 15 nm) were applied. The groups were as follows: red laser (RL3—5 J/cm 2 , 3 s and RL5—8.3 J/cm 2 , 5 s, 1.66 W/cm 2 ); infrared laser (IrL3—5 J/cm 2 , 3 s and IrL5–8.3 J/cm 2 , 5 s); LED (LED3—3 s and LED5—5 s, 0.02 J/cm 2 , 0.885 W/cm 2 ); positive (C+, 10% FBS) and negative control (C−, 1% FBS). For alkaline phosphatase (ALP) and mineralization assays, the cells were cultured in REG (DMEM 10% FBS) and OST medium (DMEM 10% FBS, 50 μg/mL ascorbic acid, 10 mM β-glycerophosphate). Statistical analysis was performed using ANOVA and Tukey’s tests ( p < 0.05). RL5 and LED5 increased proliferation, in vitro wound closure, ALP, and mineralization in rGO cells ( p < 0.05). PBM with red laser and LED induced mineralization by itself, without osteogenic medium, not observed for infrared laser ( p < 0.05). A sum of effects was observed in osteogenic medium and PBM by infrared, red laser, and LED (5 s). Red laser and LED increased proliferation, migration, and secretory phases in rGO cells in a dose-dependent manner. PBM with red laser and LED promotes osteogenic induction by itself. PBM with infrared laser and osteogenic medium potentializes mineralization. | Laser and LED photobiomodulation effects in osteogenic or regular medium on rat calvaria osteoblasts obtained by newly forming bone technique | 10.1007/s10103-020-03056-5 |
2021-04-01 | For computational arithmetic, a full adder is the primary logic units in VLSI applications. A new full adder circuit design has been presented in this article which is based on input switching activity pattern and gate diffusion input (GDI) technique. The adder has been designed in two stages. The first stage is an XOR–XNOR module, whereas, the final stage is for the required outputs. By using the switching activity pattern of inputs and GDI techniques at each stage, the switching activities of the transistors have been minimized. This improves delay, power consumption and computational complexity. The adder has been designed and evaluated by using the synopsis tool and compared with different existing adder cells found in the literature. It is found that the presented adder shows an improvement at least 72.86% and 66.67% in terms of speed and energy consumption, respectively. Extensive performance analyses of the full adder have also been evaluated at 32 nm CMOS and 32 nm CNFET technology node which shows promising performances in both the technology nodes. | Fast and High-Performing 1-Bit Full Adder Circuit Based on Input Switching Activity Patterns and Gate Diffusion Input Technique | 10.1007/s00034-020-01550-3 |
2021-04-01 | Abstract This works deals with isolation of chloro complexes of platinum metals, in particular [IrCl 6 ] 3– and [IrCl 6 ] 2– , from hydrochloric acid solutions with different content of chloride ions by sorption method. Sorbents used were modified silicas obtained by the chemical grafting of short-chain polyethyleneimines (PEI) to their surface followed by crosslinking and quaternization to form a thin layer of supported ionic liquids. A PEI with low molecular weight (MW 600, ~12 units) and preferably linear molecules was selected. Mobility of polyethyleneimine chains determines the possibility of its multipoint grafting to silica surface. Procedures for the synthesis of sorbents and their structural characteristics have been reported. Dependences of Ir(III) and Ir(IV) sorption on HCl, H + , and Cl – concentration have been revealed. Sorption equilibrium is reached over 2–5 min, which is typical for materials based on mesoporous silica and indicates anion-exchange mechanism of binding. A hot NH 4 Cl solution has been used for the quantitative desorption of Ir(IV) ions. The sorbents were tested for separation of Ir(IV) from Pt(IV) and Rh(III). Obtained results may be recommended for the recovery of platinum metal ions from chloride solutions of complex composition. | Sorption of Iridium Complexes with Supported Ionic Liquids | 10.1134/S0036023621040045 |
2021-04-01 | The non- Saccharomyces yeasts represent a great richness for the production of new and different types of beers. In this study, the role of eight yeast strains ( Saccharomycodes ludwigii , Metchnikowia pulcherrima , Hanseniaspora uvarum , Hanseniaspora osmophila and Brettanomyces bruxellensis ) isolated from Asturian cider and belonging to five unconventional species was evaluated. None of the strains could ferment the main wort sugars (maltose and maltotriose). Beers produced by S. ludwigii strains showed the highest ethanol content (21.6 g/L) and interestingly high levels of fusel alcohols, fatty esters and isoamyl acetate. Strains of B. bruxellensis were the only ones that produced ethyl phenols and they also generated the highest concentration of fatty acids and their ethyl esters. Sucrose was not utilised by Metschnikowia and Hanseniaspora strains, resulting in low ethanol formation (4.7 g/L), although these yeasts differed in terms of their synthesis of volatile compounds. Larger amounts of fatty acid esters were detected in beers fermented by H. osmophyla 10, while H. uvarum 62 produced more 2-phenylethyl acetate and ethyl acetate. M. pulcherrima 301 stands out for its low fermentative capacity and production of volatile compounds. These results show the interest of non- Saccharomyces strains in the production of beers with low alcohol content and their potential use in developing new beer styles in sequential or mixed inoculations with S. cerevisiae strains. | Evaluation of indigenous non-Saccharomyces cider yeasts for use in brewing | 10.1007/s00217-020-03665-y |
2021-04-01 | Low-salinity waterflooding (LSWF) has, in the past decade, attained a lot of attention to enhance oil recovery. In LSWF, diluted water is injected into an oil reservoir to improve oil recovery. The injected low-saline water changes the wettability of the reservoir, which leads to higher oil recovery. The recovery of an oil reservoir can be predicted from simulators, which are tedious, expensive, and time-consuming. Therefore, there is a need for a simple, quick, and inexpensive substitute to predict the oil recovery factor for low-salinity waterfloods. This paper presents a novel empirical correlation based on a feed-forward neural network to predict LSWF recovery efficiency in a heterogeneous reservoir at and beyond water breakthrough. The proposed model is valid for a broad range of dimensionless input parameters—degree of dilution of high saline water, mobility ratio, degree of reservoir heterogeneity, permeability anisotropy ratio, API gravity, and production water cut. The new empirical correlation was developed using 20,000 simulated data points obtained from simulation results to cover a wide range of input values. The LSWF simulation model was developed and validated with a model of a real carbonate reservoir located in the Madison formation in Wyoming. The artificial neural network (ANN) model parameters were optimized by conducting extensive sensitivities of ANN parameters (hidden layer neurons, training algorithms, and transfer functions). Moreover, an interesting trend analysis was conducted to validate the physical behavior of the ANN model, and a comparison with the unseen dataset was performed. To evaluate the performance of the newly developed correlation, three statistical indices were used, including the average absolute percentage error (AAPE). AAPE was 1.69% and 1.84% for the training and testing datasets, respectively. The proposed ANN model is limited to a single-stage, low-saline waterfloods for a 5-spot pattern. | Data-Driven Modeling Approach to Predict the Recovery Performance of Low-Salinity Waterfloods | 10.1007/s11053-020-09803-3 |
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