Cerebral ischemia/reperfusion (I/R) injury severely threatens human life, while the potential mechanism underlying it is still need further exploration. The rat model of cerebral I/R injury was ...established using middle cerebral artery occlusion (MCAO). The rat microvascular endothelial cell line bEND.3 was exposed to oxygen–glucose deprivation/reperfusion (OGD/R) to mimic ischemic condition in vitro. Evans blue was performed to determine the blood–brain barrier (BBB) permeability. Real-time PCR and western blot were performed to determine gene expression in mRNA and protein level, individually. Luciferase reporter assay was conducted to determine the relationship between miR-539 and MMP-9. The infarct volume and BBB permeability of cerebral (I/R) rats were significantly greater than Sham group. The expression of miR-539 was decreased, while MMP-9 was increased in the brain tissues of I/R injury rats and OGD/R pretreated bEND.3. Up-regulated miR-539 in OGD/R pretreated bEND.3 significantly promoted the BBB permeability. MiR-539 targets MMP-9 to regulate its expression. OGD/R treatment significantly promoted the BBB permeability in bEND.3, miR-539 mimic transfection abolished the effects of OGD/R, while co-transfected with pcDNA-MMP-9 abolished the effects of miR-539 mimic. MiR-539 targets MMP-9 and further regulates the BBB permeability in cerebral I/R injury.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
•Effects of adhesive and CFRP on bond behaviors between CFRP and steel were evaluated.•Bond–slip models for bonding interfaces with different adhesives/CFRPs were built.•Maximum interfacial shear ...stresses linearly correlate with elastic moduli of adhesive for interfacial failure.
The bond between carbon fiber-reinforced polymer (CFRP) composites and steel is a key issue in CFRP-strengthened steel structures. The determination of key parameters in the bond strength model remains debatable. We studied the bond behavior between CFRP and steel, focusing on the effects of different types of epoxy adhesive and CFRP on the failure modes, bond–slip relationships, and bond strength parameters. The results show that due to the use of various materials, some specimens fail in interface debonding characterized by brittle failure, whereas others have cohesive failure or CFRP delamination characterized by ductile failure. The bond–slip models showed gentle-slope descending branches for interfaces with ductile failure, which is missing in brittle failure. The bond–slip relationships of most specimens can be simplified as bilinear models. However, trilinear models should be used for the specimens failing in the delamination and tearing of CFRP. As for the modes of interface debonding and CFRP superficial delamination, the maximum shear stresses in the interface linearly correlate with the elastic moduli of adhesive. The nonlinear mechanical behavior of interfaces can be well simulated by a cohesive zone model.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Trehalose-6-phosphate phosphatases (TPPs), which are encoded by members of the TPP gene family, can improve the drought tolerance of plants. However, the molecular mechanisms underlying the dynamic ...regulation of TPP genes during drought stress remain unclear. In this study, we explored the function of an Arabidopsis TPP gene by conducting comparative analyses of a loss-of-function mutant and overexpression lines.
The loss-of-function mutation of Arabidopsis thaliana TPPF, a member of the TPP gene family, resulted in a drought-sensitive phenotype, while a line overexpressing TPPF showed significantly increased drought tolerance and trehalose accumulation. Compared with wild-type plants, tppf1 mutants accumulated more H
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under drought, while AtTPPF-overexpressing plants accumulated less H
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under drought. Overexpression of AtTPPF led to increased contents of trehalose, sucrose, and total soluble sugars under drought conditions; these compounds may play a role in scavenging reactive oxygen species. Yeast one-hybrid and luciferase activity assays revealed that DREB1A could bind to the DRE/CRT element within the AtTPPF promoter and activate the expression of AtTPPF. A transcriptome analysis of the TPPF-overexpressing plants revealed that the expression levels of drought-repressed genes involved in electron transport activity and cell wall modification were upregulated, while those of stress-related transcription factors related to water deprivation were downregulated. These results indicate that, as well as its involvement in regulating trehalose and soluble sugars, AtTPPF is involved in regulating the transcription of stress-responsive genes.
AtTPPF functions in regulating levels of trehalose, reactive oxygen species, and sucrose levels during drought stress, and the expression of AtTPPF is activated by DREB1A in Arabidopsis. These findings shed light on the molecular mechanism by which AtTPPF regulates the response to drought stress.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•A sampling method is proposed for high-dimensional time-variant reliability analysis.•Time-variant system is reinterpreted as multi-response time-invariant system.•The proposed method is tested on ...two high-dimensional dynamic reliability problems.•Results are compared to MCS and the original subset simulation.
A new sampling-based method is proposed for high-dimensional time-variant reliability analysis with both random variables and random process as inputs. The new method employs the series expansion methods, e.g., the Karhunen-Loève expansion, to represent the input random process into a set of random variables. Based on the concepts of composite limit state, the time-variant reliability analysis is converted into a series system reliability problem with multiple responses. Then the generalized subset simulation is applied to compute cumulative failure probabilities which are further used to interpolate a completely cumulative failure probability curve for a given time interval. The advantage of the proposed method is that only a single run can provide a cumulative failure probability curve instead of repeated runs. Two high-dimensional time-variant reliability problems with input random process are used to demonstrate the performance of the proposed method.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In two theorems presented herein, we prove and subsequently demonstrate in several numerical examples involving homogeneous deformation that for isotropic materials, hyper-elasto-plasticity models ...based on the multiplicative decomposition of the deformation gradient coincide with an additive hypo-elasto-plasticity model (see Section 3.2) that employs the spin tensor based on the modified kinetic logarithmic rate. In the absence of strain-induced anisotropy (characterized by kinematic hardening herein), this objective stress rate coincides with the kinetic logarithmic rate recently developed by Jiao and Fish, 2017. We also show that other well-known additive decomposition models, such as those based on the Jaumann and logarithmic rates, may considerably deviate from the multiplicative model.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
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•The effects of polystyrene nanoplastics on juvenile M. nipponense were evaluated.•Nanoplastics reduced the survival rate of juvenile shrimp.•Nanoplastics induced oxidative stress and ...stimulated immune defense in shrimp.•High concentrations of nanoplastics had toxic effects on shrimp viability.
Nanoplastics are widely distributed in aquatic environments, and nanoplastic pollution has become a global concern. However, few studies have evaluated the toxicity of nanoplastics to freshwater crustaceans. In this study, by adding different concentrations of nanoplastics to water, we explored the effects of nanoplastics on the survival, antioxidant activity, immune enzyme activity, and related gene expression levels in juvenile Macrobrachium nipponense. The results showed that the 96 -h half-lethal concentration of nanoplastics to juvenile shrimp was 396.391 mg/L. As the concentration of nanoplastics increased, the activities of antioxidant enzymes generally decreased, while the contents of hydrogen peroxide and lipid peroxidation products increased. The activities of non-specific immune enzymes first increased and then decreased with increasing nanoplastic concentration. The trends in the expressions of antioxidant-related genes were generally consistent with those in the activities of antioxidant enzymes. As the nanoplastic concentration increased, the expressions of immune-related genes generally increased at first and then decreased. These results indicate that low concentrations of nanoplastics (5 mg/L) may enhance the viability of juvenile shrimp, whereas high concentrations (10,20, 40 mg/L) have inhibitory and/or toxic effects. The findings provide basic information on the toxic effects of nanoplastics in juvenile shrimp.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Hengshan goat meat produced exclusively in Shaanxi province of China is the product of national geographical indication. In current study, nutritional and safety indexes of Hengshan goat leg meat ...were investigated and the quality changes induced by seven commonly used processing methods were systematically evaluated. Comparing with control, meats treated with thermal processing demonstrated decreased redness, enhanced texture properties, increased protein, fat and mineral contents, as well as sharply raised fatty acids. Amino acid contents in pan‐fried, deep‐fried, and roasted samples were reduced with the most obvious valine scores declined 15%, 13%, and 21%, respectively. Also, thermal treatments conducted in smoke exposure circumstances caused mass formation of nitrite and polycyclic aromatic hydrocarbons (PAHs), evidenced by the 5.8‐fold, 3.3‐fold, and 3.8‐fold increments of nitrite contents in pan‐fried, deep‐fried, and roasted meats, respectively, and the appearance of six extra PAHs. Steaming, boiling, and braising were proved to be suitable processing methods for preserving better nutritional values while delivering less carcinogenic hazard. Our results established nutritional database for Hengshan goat leg meat and provide reference for choosing its reasonable thermal processing pattern.
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Processed meats showed decreased redness, enhanced texture properties, increased protein, fat and mineral contents, as well as sharply raised fatty acids compared with those of raw meat. Steaming, boiling, and braising delivered more balanced nutrition and less carcinogens in contrast to meats processed with other methods. Frying and roasting caused low amino acid levels and formed mass nitrite and polycyclic aromatic hydrocarbons in meats. Our results established nutritional database for Hengshan goat leg meat and provide reference for its reasonable thermal processing.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Owing to limited data, we conducted a meta-analysis to re-evaluate the relationship between obesity and coronavirus-2019 (COVID-19). Literature published between 1 January 2020 and 22 August 2020 was ...comprehensively analysed, and RevMan3.5 was used for data analysis. A total of 50 studies, including data on 18 260 378 patients, were available. Obesity was associated with a higher risk of severe acute respiratory syndrome-coronavirus 2 (SARS-CoV2) infection (odds ratio (OR): 1.39, 95% confidence interval (CI) 1.25–1.54; P < 0.00001) and increased severity of COVID-19 (hospitalisation rate: OR: 2.45, 95% CI 1.78–3.39; P < 0.00001; severe cases: OR: 3.74, 95% CI 1.18–11.87; P: 0.02; need for intensive care unit admission: OR: 1.30, 95% CI 1.21–1.40; P < 0.00001; need for invasive mechanical ventilation: OR: 1.59, 95% CI 1.35–1.88; P < 0.00001 and mortality: OR: 1.65, 95% CI 1.21–2.25; P: 0.001). However, we found a non-linear association between BMI and the severity of COVID-19. In conclusion, we found that obesity could increase the risk of SARS-CoV2 infection and aggregate the severity of COVID-19. Further studies are needed to explore the possible mechanisms behind this association.
Hydrophobic iron oxide nanoparticles grafted with hydrophobic polymer chains of varying molecular weights and graft densities are synthesized to underpin the role of brush entanglement and dipolar ...forces on creating nanostructures. Grafting density on magnetic nanoparticles is controlled in grafting-to method by changing the concentration of functionalized polymer in solution. The grafting density and brush length have varied systemically to observe the changes in nanostructures. Bridging between grafted chains and dipolar forces become effective only at low grafting density and result in long chains of particles. We demonstrate experimentally that structural transition of magnetic nanoparticles is controlled with the balance between grafted chain entanglements and dipolar forces.
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IJS, KILJ, NUK, PNG, UL, UM
Quick: An exogenously induced quick increase of the H2S concentration (80 s) in MCF‐7 cells can be visualized by ratiometric imaging using a new probe (CouMC) that can target mitochondria. CouMC was ...constructed by combining merocyanine and coumarin fluorophores. The selective nucleophilic addition of HS− to the merocyanine derivative at neutral pH is crucial for the rapid H2S detection.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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