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181.
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Main objective of present study is to analyze the mixed convective peristaltic transport of water based nanofluids using five different nanoparticles i.e. (Al2O3, CuO, Cu, Ag and TiO2). Two thermal conductivity models namely the Maxwell''s and Hamilton-Crosser''s are used in this study. Hall and Joule heating effects are also given consideration. Convection boundary conditions are employed. Furthermore, viscous dissipation and heat generation/absorption are used to model the energy equation. Problem is simplified by employing lubrication approach. System of equations are solved numerically. Influence of pertinent parameters on the velocity and temperature are discussed. Also the heat transfer rate at the wall is observed for considered five nanofluids using the two phase models via graphs.  相似文献   
183.
Severe fever with thrombocytopenia syndrome virus (SFTSV) is a tick-borne emerging phlebovirus with high mortality rates of 6.0 to 30%. SFTSV infection is characterized by high fever, thrombocytopenia, leukopenia, hemorrhage and multiple organ failures. Currently, specific therapies and vaccines remain elusive. Suitable small animal models are urgently needed to elucidate the pathogenesis and evaluate the potential drug and vaccine for SFTSV infection. Previous models presented only mild or no pathogenesis of SFTS, limiting their applications in SFTSV infection. Therefore, it is an urgent need to develop a small animal model for the investigation of SFTSV pathogenesis and evaluation of therapeutics. In the current report, we developed a SFTSV infection model based on the HuPBL-NCG mice that recapitulates many pathological characteristics of SFTSV infection in humans. Virus-induced histopathological changes were identified in spleen, lung, kidney, and liver. SFTSV was colocalized with macrophages in the spleen and liver, suggesting that the macrophages in the spleen and liver could be the principle target cells of SFTSV. In addition, histological analysis showed that the vascular endothelium integrity was severely disrupted upon viral infection along with depletion of platelets. In vitro cellular assays further revealed that SFTSV infection increased the vascular permeability of endothelial cells by promoting tyrosine phosphorylation and internalization of the adhesion molecule vascular endothelial (VE)–cadherin, a critical component of endothelial integrity. In addition, we found that both virus infection and pathogen-induced exuberant cytokine release dramatically contributed to the vascular endothelial injury. We elucidated the pathogenic mechanisms of hemorrhage syndrome and developed a humanized mouse model for SFTSV infection, which should be helpful for anti-SFTSV therapy and pathogenesis study.  相似文献   
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The snow leopard (Panthera uncia) inhabits one of the most challenging environments on Earth, referred to as the ‘third pole’. Only a fraction of its vast range has been explored thus far, owing to myriad of barriers inflicted by the remote terrain and socio-ecological realities of the landscapes. Understanding distribution patterns of species is essential to devise practical management measures. This study aimed to understand the distribution pattern and factors influencing occupancy of snow leopard in the Pamir Mountain range through sign-based occupancy modelling. Our study confirmed that the Pamir range is a snow leopard stronghold, with occupancy estimated at 0.57 ± 0.02. The topographic features positively influenced the detection probability (p = 0.37 ± 0.005) of snow leopards. Occupancy was influenced by mean annual precipitation (β = -6.12 ± 1.8), density of roads (β = -1.61 ± 0.6) and water sources (β = 0.74 ± 0.4). Our findings underpin that sign-based distribution surveys provide vigorous scientific knowledge about elusive species and merit replication being used for other species. We propose to redefine the protected area boundaries based on ecological knowledge and encourage transboundary cooperation to safeguard snow leopards at a landscape scale.  相似文献   
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Molecular Biology Reports - Angiotensin II (Ang II: a truncated octapeptide of angiotensinogen, AGT) and 11-β-hydroxylase influence regulation of blood pressure. Dysregulation of Ang II and...  相似文献   
188.
BioControl - Rice bakanae disease, caused by Fusarium fujikoroi, is an economically important disease that poses a threat to rice cultivation. It causes serious yield losses quantitatively and...  相似文献   
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Tobacco (Nicotiana tabacum) serve as the top leading commercial, non-food, and model crop worldwide. Cyclic nucleotide-gated channels (CNGCs) are ligand-gated, calcium-permeable, divalent, cation-selective channels, involved in important biological functions. Here, we systematically characterized thirty-five CNGC genes in the genome of Nicotiana tabacum, and classified into four phylogenetic groups. Evolutionary analysis showed that NtabCNGC family of N. tabacum originated from the parental genome of N. sylvestris and N. tomentosiformis, and further expanded via tandem and segmental duplication events. Tissue-specific expression analysis showed that twenty-three NtabCNGC genes are involved in the development of various tobacco tissues. Subsequent RT-qPCR analyses indicated that these genes are sensitive towards external abiotic and biotic stresses. Notable performances were exhibited by group-I and IV CNGC genes against black shank, Cucumber mosaic virus, Potato virus Y, cold, drought, and cadmium stresses. Our analyses also suggested that NtabCNGCs can be regulated by phosphorylation and miRNAs, and multiple light, temperature, and pathogen-responsive cis-acting regulatory elements present in promotors. These results will be useful for elaborating the biological roles of NtabCNGCs in tobacco growth and development.  相似文献   
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IntroductionWeight loss is common in Parkinson’s Disease (PD) and sometimes may precede the diagnosis. Weight loss is associated with multiple factors but its impact on health-related quality of life (HRQL) in PD remains unknown. We sought to investigate the factors associated with weight change and to quantify its effect on HRQL.MethodsThe National Parkinson Foundation Quality Improvement Initiative (NPF-QII) data was used to analyze PD patients longitudinally between two visits, separated by 12±6 months. Multiple linear regression analyses were used to assess the associations between baseline covariates and body weight change per month, and to evaluate whether, and to what degree, Parkinson’s Disease Questionnaire (PDQ-39) scores were affected.ResultsA higher Hoehn & Yahr stage, higher number of comorbidities, older age, lower MOCA estimate, and higher rate of levodopa usage were observed in patients who lost weight. Multivariate regression analysis indicated that age and levodopa usage were significantly associated with weight loss. Furthermore, monthly body weight loss was significantly associated with HRQL decline in PD patients. Loss of 1 lb (0.45 kg) per month was associated with a decline in QOL: an increase of 0.5% in PDQ-39 Summary Index score (p=0.004), and 1.1% and 1.5% increases in the mobility and ADL dimensions, respectively.ConclusionWeight loss in PD is common and seems to correlate with worsened HRQL. Awareness of factors associated with weight loss and its relation to HRQL may help practitioners improve patient management and expectations.  相似文献   
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