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Partial discharge characteristics of interturn insulation used for inverter-fed traction motor under bipolar impulses

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Science China(Technological Sciences) 2012年第8期55卷 2346-2354页

作者： WU GuangNing CAO KaiJiang LUO Yang GAO Bo WANG Peng ZHANG YiQiang xu huihui School of Electrical Engineering Southwest Jiaotong UniversityChengdu 610031China

Inverter-fed traction motors,which are employed for electric-multiple-units(EMUs),are subjected to Pulse Width Modulated(PWM) impulse *** voltage has fast rise/fall time and high repetition *** failure mechanism of insulation under impulses is different from that of standard 50 Hz sinusoidal *** discharge(PD) characteristics(discharge number,mean discharge quantity and phase resolved partial discharge(PRPD) pattern) with different frequencies and different rise times of impulse voltage were *** results reveal that discharge number and mean discharge quantity increase,while PRPD pattern moves to the zero of impulse voltage with decrease of rise *** number and PRPD pattern follow that trend with increase of frequency,the value of mean discharge quantity is *** effect of the deposited space charges on PD was *** pattern moves to the zero of bipolar impulse voltage due to the role of space charges,with increase of frequency and decrease of rise *** is revealed that available discharge time is prolonged and overvoltage across the cavity increases with augment of frequency,which results in discharge number *** the condition of shortening the rise time,with the same statistical time lag tL,△V would increase if dV/dt is higher,which results in enhancement of discharge *** number increases with reduction of rise time,because the decreased multiple of td is lower than the increased multiple of dV/*** of PD characteristics and role of space charges is helpful to the exploration of the destructive mechanism of insulating materials under bipolar impulse.

关键词： partial discharges bipolar impulse interturn insulation electric-multiple-units memory effect space charges

Modulation of HLA Expression in Human Cytomegalovirus Immune Evasion

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Cellular & Molecular Immunology 2007年第2期4卷 91-98页

作者： Aifen Lin huihui xu Weihua Yan Medical Research Center Wenzhou Medical College Affiliated Taizhou Hospital of Zhejiang Province Linhai Zhejiang 317000 China

Human cytomegalovirus （hCMV） has evolved multiple mechanisms to escape the host immune recognition and innate or adaptive immune responses. Among them, hCMV has developed strategies to modulate the expression and/or function of human leukocyte antigens （HLAs）, including by encoding series of infection stage-dependent hCMV proteins to detain and destroy the expression of HLA molecules on the surface of infected cells. This disturbs the antigen presentation and processing, by encoding MHC class I homologues or selective up-regulation of particular HLA class I molecules binding to NK cell inhibitory receptors, and by encoding specific ligand antagonists to interfere with NK cell activating receptors. Here we discussed the molecular mechanisms utilized by the hCMV to alter the formation, transportation and expression of HLA antigens on the infected cell surface. The knowledge about hCMV modulating HLA expression could benefit us to further understand the pathogenesis of viral diseases and may eventually develop novel effective immunotherapies to counteract viral infections and viral associated diseases.

关键词： HLA human cytomegalovirus NK cell T lymphocyte

Direct estimation of rupture depths of earthquake faults from coseismic surface deformation

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Science China Earth Sciences 2014年第5期57卷 1986-1994页

作者： FU Zhen HU CaiBo ZHANG HaiMing xu huihui CAI YongEn Chinese Academy of Geological Sciences College of Earth Science University of Chinese Academy of Sciences School of Earth and Space Sciences Peking University

The rupture dimensions of earthquake faults are important parameters for characterizing earthquake ruptures and ground motions. Two key parameters to be determined are the rupture depth and dip angle of earthquake faults. Dislocation theory in an elastic half space indicates that if a seismic rupture directly runs up to the ground surface, there exist zero points of horizontal strain in the surface deformation, which correspond to the rupture depths, except for pure strike-slip faults. In this study, we use numerical simulations to investigate the possibility of inferring rupture depths from zero-strain points for cases of buried faults and heterogeneous media. The results show that the correspondence of zero-strain points to the rupture depths can be influenced by the heterogeneity of the underground media and the stress field. For buried faults, the correspondence relationship is approximately valid when the fault depth is <1 km. In addition, the range of earthquake fault dip angles can be estimated by horizontal displacements on the ground. We also study how to determine the rupture depths of faults from InSAR data after large earthquakes, and successfully apply the method to the 2008 Wenchuan earthquake. The method proposed here, which determines the parameters of fault geometry according to surface deformation, is simple and easy to perform. With independent of aftershocks, it can provide valuable constraints to kinematic inversions.

关键词： surface deformation zero-strain points rupture depths dip angles of faults InSAR

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Protein inhibitor of activated STAT 4(PIAS4) regulates liver fibrosis through modulating SMAD3 activity

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The Journal of Biomedical Research 2016年第6期30卷 496-501页

作者： huihui xu Zhiwen Fan Wenfang Tian Yong xu Key Laboratory of Cardiovascular Disease and Molecular Intervention Department of PathophysiologyNanjing Medical University

Excessive fibrogenesis disrupts normal liver structure,impairs liver function,and precipitates the development of cirrhosis,an irreversible end-stage liver disease.A host of factors including nutrition surplus contribute to liver fibrosis but the underlying mechanism is not fully *** the present study,we investigated the involvement of protein inhibitor for activated stat 4（PIAS4）in liver fibrosis in a mouse model of non-alcoholic steatohepatitis（NASH）.We report that PIAS4 silencing using short hairpin RNA（shRNA）attenuated high-fat high-carbohydrate（HFHC）diet induced liver fibrosis in *** PCR and Western blotting analyses confirmed that PIAS4 knockdown downregulated a panel of pro-fibrogenic genes including type I and type III collagens,smooth muscle actin,and tissue inhibitors of ***,PIAS4 silencing blocked the recruitment of SMAD3,a potent pro-fibrogenic transcription factor,to the promoter regions of pro-fibrogenic genes and dampened SMAD3 acetylation likely by upregulating SIRT1 *** conclusion,PIAS4 may contribute to liver fibrosis by modulating SIRT1-dependent SMAD3 acetylation.

关键词： liver fibrosis PIAS4 SMAD3 acetylation transcriptional regulation

Q345-TA2的动态流动应力特征和本构关系

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稀有金属材料与工程 2016年第12期45卷 3192-3196页

作者：江海涛徐惠惠北京科技大学北京100083

钛钢复合板因其优异的高强度和耐腐蚀性能已越来越多的被应用于动态环境下。采用Gleeble-3500热模拟试验机和分离式霍普金森压杆(SHPB)装置,对Q345-TA2钛钢复合板进行准静态和高应变速率压缩试验。结果表明:Q345-TA2钛钢复合材料具有应... 详细信息

钛钢复合板因其优异的高强度和耐腐蚀性能已越来越多的被应用于动态环境下。采用Gleeble-3500热模拟试验机和分离式霍普金森压杆(SHPB)装置,对Q345-TA2钛钢复合板进行准静态和高应变速率压缩试验。结果表明:Q345-TA2钛钢复合材料具有应变率增强效应、增塑效应、绝热温升软化作用,但在准静态和动态冲击各自分区范围内,对应变率变化不甚敏感。在考虑绝热温升的基础上,对J-C本构模型进行修正,得到了可用于对冲击载荷作用下进行结构分析的材料本构模型,结果较好。

关键词：钛钢复合板高应变速率流动应力 J-C本构模型

中国政府区域环境治理的影响因素组态与路径研究

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中国人口·资源与环境 2023年第9期33卷 98-110页

作者：刘芳徐慧慧山东师范大学公共管理学院山东济南250014 中央民族大学国家安全研究院北京100081

中国政府区域环境治理成效显著但也存在异质性,如何打破线性思维把握环境治理要素与模式成为亟须解决的问题。该研究基于中国环境治理概念模型,构建了涵盖主体行为(政府主导、公民参与、政社协同)、主体关系优化(制度创新、技术创新),... 详细信息

中国政府区域环境治理成效显著但也存在异质性,如何打破线性思维把握环境治理要素与模式成为亟须解决的问题。该研究基于中国环境治理概念模型,构建了涵盖主体行为(政府主导、公民参与、政社协同)、主体关系优化(制度创新、技术创新),以及规则对主体间关系影响(政策压力)的影响因素框架,采用清晰集定性比较分析方法,对48个政府区域环境治理案例进行单因素变量分析和条件组合分析。结果发现:①中国区域环境治理成效是多要素联合驱动作用的结果,要素间以联动匹配的方式形成制度创新、协同治理、技术创新三种环境治理模式,且有各自的要素差异及共性、适用范围、促发机制与特征,并存在联动耦合、互相促进和共同进化关系。②在制度创新模式中,政府主导发挥核心驱动作用,通过创新环境治理体系、治理工具等,与社会建立了良性合作治理关系,共同推进制度作用发挥。③在协同治理模式中,政府主导、政社协同、公民参与是核心条件,该模式由区域政府主导组织形成良性合作,或者由公民个人或社会团体参与博弈形成合作。④在技术创新模式中,技术创新为核心条件,政府主导为补充条件,该模式往往是由政府通过项目建设资助或推动的,依托大数据、互联网、人工智能、云计算等前沿技术促进环境治理思维、流程与能力的优化。⑤政府主导贯穿各种模式,但不同场景下的势力强弱使得治理产生不同结果。这意味着,政府区域环境治理应依据区域特征和模式特点灵活选择多要素组合路径,由此建议各区域政府环境治理要完善多元监督体系与沟通场域,积极推进制度创新和协同治理,并进一步在学习创新和区域协作中挖掘技术创新潜力,从而实现非线性思维转向以及治理主体行为与关系的优化。

关键词：政府环境治理影响因素清晰集定性比较分析

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Are “night owls” or “morning larks” more likely to delay sleep due to problematic smartphone use? A cross-lagged study among undergraduates

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Are “night owls” or “morning larks” more likely to delay...

Diagnostic Accuracy of High-risk HPV Genotyping in Women with High-Grade Cervical Lesions:Evidence for renewed the Cervical Cancer Screening Strategy in China

第二十五届全国心理学学术会议

作者： Chengjia Zhao Jiankang He huihui xu Jingjing Zhang Guohua Zhang Guoliang Yu

Sleep is an important physiological process in life, but "staying up late" has become a "world problem" for contemporary people, particularly among university students. Sleep procrastination is associated with a wide variety of indicators, such as sleep biorhythms and problematic smartphone use. The current study examined the longitudinal reciprocal relationships between problematic smartphone use and sleep ***, the research examined sleep biorhythms differences in relationships between those two variables. A total of 1423 Chinese university students participated in the two-wave study. The results found there were reciprocal relationships between problematic smartphone use and sleep procrastination. Additionally, sleep biorhythms moderated the relationships between problematic smartphone use and sleep procrastination(i.e.,problematic smartphone use at T1 can significantly predict sleep procrastination at T2 for the morning larks group,whereas problematic smartphone use at T1 cannot significantly predict sleep procrastination at T2 for the night owls group). The problematic smartphone use and the difference in sleep biorhythms should be taken into account while developing interventions for sleep procrastination

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Diagnostic Accuracy of High-risk HPV Genotyping in Women wit...

Lymphocytopenia and Neutrophilia Deteriorate at the Lowest Oxygenation Index Timepoint in COVID-19 Patient

浙江省免疫学会第十次学术大会

作者： huihui xu Aifen Lin Weiwu Shi Yang Zhang Xiujuan Shao Weihua Yan Medical Research Center Taizhou Hospital of Zhejiang ProvinceWenzhou Medical University Human Tissue Bank Taizhou Hospital of Zhejiang ProvinceWenzhou Medical University Department of gynecology Taizhou Hospital of Zhejiang ProvinceWenzhou Medical University

Currently,clinical data for primary HPV screening alone are lacking in ***,we evaluate cervical cancer screening with primary HPV genotyping,as well as possible future screening ***,high-risk HPV(hrHPV) prevalence was 18.2%among hospital-based population in Taizhou *** cervical intraepithelial neoplasia 2 or worse(CIN2+),the sensitivity of primary hrHPV genotyping strategy and current cervical cancer screening strategy were 93.5%,and47.8%,respectively;whereas the specificity was 17.5%,and 69.1%,*** cervical screening strategy had slightly higher positive predictive values(28.7%) for CIN2+ than hrHPV genotyping strategy(22.8%),whereas primary hrHPV genotyping strategy demonstrated higher negative predictive values(91.2%)than current cervical screening strategy(83.5%).Compared to HPV35/39/45/51/56/59/66/68 genotypes,the odds ratios(OR) for CIN2+ in HPV16/18/31/33/52/58 infection women were 3.2(95%confidence interval[CI]2.3-4.1).Primary hrHPV genotyping strategy provides a better predictive value than HPV 16/18 genotyping alone in guiding the clinical management of the current cervical cancer *** testing without adjunctive cytology may be sufficiently sensitive for primary cervical cancer screening.

关键词： high-risk human papillomavirus genotyping diagnosis high-grade cervical lesion cervical cancer screening

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International Journal of Clinical Medicine 2020年第12期11卷 810-822页

作者： Yiwen xu Weijun Hong Gang Wu Weiling Li Chunqiang xu Xiaofei Hu Meixian Zhang huihui xu En Wang Shaofa Ke Xiaoping Jin Department of Neurology Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University Linhai China The First Clinical Medical College Wenzhou Medical University Wenzhou China Department of Pharmacy Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University Linhai China Public Experiment Center Medical Research Center Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University Linhai China Laboratory of Gynecologic Oncology Medical Research Center Taizhou Hospital of Zhejiang Province Affiliated to Wenzhou Medical University Linhai China

Objective: Coronavirus disease 2019 (COVID-19) spread throughout the world and caused hundreds of thousands of infected people to death. However, the pathogenesis of severe acute respiratory syndrome coronavirus-2 (SARS COV-2) is poorly understood. The objective of this study is to retrospectively explore the pathogenesis of COVID-19 from clinical laboratory findings, taking disease progression into account. Methods: A single-centered, retrospective study was carried out, which included moderate (n = 76) and severe COVID-19 cases (n = 22). The difference of laboratory findings from blood routine examination and hepatorenal function test were retrospectively evaluated between the state of moderate and severe. The disease progression was indicated by oxygenation index. Results: Age is a risk factor for disease progression from moderate to severe. Lymphocytopenia, neutrophilia, liver and kidney function decreasement occurred in severe patients on admission, compared with moderate patients. Lymphocytopenia and neutrophilia deteriorated at the lowest oxygenation index timepoint in the severe patients. And the oxygenation index was associated with ratio of lymphocyte and neutrophil in COVID-19 patients. Conclusions: Lymphocytopenia and neutrophilia, which deteriorate in the progression of severe patients, are the main pathogenesis of COVID-19. More measures need to be taken to control lymphocytopenia and neutrophilia in severe COVID-19. Oxygenation index presented potentiality as predictor on the progression of COVID-19.

关键词： COVID-19 Oxygenation Index Lymphocytopenia Neutrophilia Glucocorticoids