126 research outputs found
A two-step sensitivity analysis for hydrological signatures in Jinhua River Basin, East China
This is the author accepted manuscript. The final version is available from Taylor & Francis via the DOI in this record.Parameter calibration and sensitivity analysis are usually not straightforward tasks for distributed hydrological models, owing to the complexity of model and large number of parameters. A two-step sensitivity analysis approach is proposed for analyzing the hydrological signatures based on the Distributed Hydrology-Soil-Vegetation Model in Jinhua River Basin, East China. A preliminary sensitivity analysis is conducted to obtain influential parameters via Analysis of Variance. These parameters are further analyzed through a variance-based global sensitivity analysis method to achieve robust rankings and parameter contributions. Parallel computing is designed to reduce computational burden. The results reveal that only a few parameters are significantly sensitive and the interactions between parameters could not be ignored. When analyzing hydrological signatures, it is found that water yield was simulated very well for most samples. Small and medium floods are simulated very well while slight underestimations happen to large floods.This work was supported by National Natural Science Foundation of China (91547106 and 51379183), Zhejiang Provincial Natural Science Foundation of China (LR14E090001), and National Key Research and Development Plan "Inter-governmental Cooperation in International Scientific and Technological Innovation"(2016YFE0122100)
The impact of SARS on hospital performance
© 2008 Chu et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens
A common polymorphism of the human cardiac sodium channel alpha subunit (SCN5A) gene is associated with sudden cardiac death in chronic ischemic heart disease
Cardiac death remains one of the leading causes of mortality worldwide. Recent research has shed light on pathophysiological mechanisms underlying cardiac death, and several genetic variants in novel candidate genes have been identified as risk factors. However, the vast majority of studies performed so far investigated genetic associations with specific forms of cardiac death only (sudden, arrhythmogenic, ischemic etc.). The aim of the present investigation was to find a genetic marker that can be used as a general, powerful predictor of cardiac death risk. To this end, a case-control association study was performed on a heterogeneous cohort of cardiac death victims (n=360) and age-matched controls (n=300). Five single nucleotide polymorphisms (SNPs) from five candidate genes (beta2 adrenergic receptor, nitric oxide synthase 1 adaptor protein, ryanodine receptor 2, sodium channel type V alpha subunit and transforming growth factor-beta receptor 2) that had previously been shown to associate with certain forms of cardiac death were genotyped using sequence-specific real-time PCR probes. Logistic regression analysis revealed that the CC genotype of the rs11720524 polymorphism in the SCN5A gene encoding a subunit of the cardiac voltage-gated sodium channel occurred more frequently in the highly heterogeneous cardiac death cohort compared to the control population (p=0.019, odds ratio: 1.351). A detailed subgroup analysis uncovered that this effect was due to an association of this variant with cardiac death in chronic ischemic heart disease (p=0.012, odds ratio =1.455). None of the other investigated polymorphisms showed association with cardiac death in this context. In conclusion, our results shed light on the role of this non-coding polymorphism in cardiac death in ischemic cardiomyopathy. Functional studies are needed to explore the pathophysiological background of this association. © 2015 Marcsa et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited
A CRISPR screen identifies a pathway required for paraquat-induced cell death
Paraquat, a herbicide linked to Parkinson's disease, generates reactive oxygen species (ROS), which causes cell death. Because the source of paraquat-induced ROS production remains unknown, we conducted a CRISPR-based positive-selection screen to identify metabolic genes essential for paraquat-induced cell death. Our screen uncovered three genes, POR (cytochrome P450 oxidoreductase), ATP7A (copper transporter), and SLC45A4 (sucrose transporter), required for paraquat-induced cell death. Furthermore, our results revealed POR as the source of paraquat-induced ROS production. Thus, our study highlights the use of functional genomic screens for uncovering redox biology
The NFKB1 polymorphism (rs4648068) is associated with the cell proliferation and motility in gastric cancer
Permafrost Thaw and Associated Settlement Hazard Onset Timing over the Qinghai-Tibet Engineering Corridor
Ultra-low overpotential and high rate capability in Li-O-2 batteries through surface atom arrangement of PdCu nanocatalysts
PdCu bimetallic nanoparticles (NPs) having mixed disordered facecentered cubic (fcc) and ordered body-centered cubic (B2-type) phases enhance the kinetics of oxygen reduction/evolution reaction by significant reduction of overpotentials, which leads to the superb round-trip efficiency of 80%. In addition, the PdCu catalyst demonstrates a remarkable cyclic enhancement in stability and an outstanding rate capability even at a high current density of 5000 mA gcarbon 1. Our first-principles calculations demonstrate that the low overpotentials of the PdCu catalyst are strongly correlated with the
weak LiO2 adsorption strength, caused by electron transfer fromCu to the top-layer Pd atoms on the surface.11011051sciescopu
Zn (II)-doped cesium copper halide nanocrystals with high quantum yield and colloidal stability for high-resolution X-ray imaging
202302 bcwwn/aRGCPublished12 month
Dragon's blood and its extracts attenuate radiation-induced oxidative stress in mice
Dragon's blood (DB) possesses great medicinal values due to the presence of several phenolic compounds. This study was designed to investigate the effects of DB and its extracts (DBEs) on oxidative stress in mice exposed to whole body Co-60-gamma irradiation (4 Gy). DB and DBEs were intragastrically administered to mice for 5 d prior to radiation. The antioxidant activities, including malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) levels in liver and spleen were measured using kits. Furthermore, DB and DBE effects were determined by organ indices and histology of liver and spleen. Our results indicated that the DB and DBE-treated groups showed a significant decrease (P < 0.05) in levels of MDA in liver and spleen compared with the irradiation-only group. Moreover, the activity of SOD, CAT and the level of GSH in liver and spleen tissue were enhanced significantly (P < 0.05) in the DB and DBE groups. DB and DBE also had a significant effect on the recovery of thymus indices. The histological observations of groups having treatment with DB and DBE indicated significant reduction in the radiation-induced damage to the liver and spleen, together with improvement in the morphology of the liver and spleen. These results suggest that DB and DBE treatment prevents radiation-induced oxidative stress injury and restores antioxidant status and histopathological changes in the liver and spleen, but there is need for further study to explore the precise molecular mechanism and strategy for optimal practical application of DB and DBE
- …