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MHC Class I Assembly Function and Intracellular Transport Routes for Hepatitis B Virus Antigen Cross-presentation by Heat Shock Protein gp96

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Infectious Diseases & Immunity 2022年第3期2卷 183-192页

作者： Lijuan Qin Yongai Liu yuxiu xu Yang Li Jun Hu Ying Ju Yu Zhang Shuo Wang Zihai Li Changfei Li Xin Li Songdong Meng CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyCenter for Biosafety Mega-ScienceChinese Academy of Sciences(CAS)Beijing 100101China University of Chinese Academy of Sciences Beijing 100190China Ohio State University OhioUSA

Background:During hepatitis B virus(HBV)infection,virus-infected hepatocytes directly cross-present viral antigens and regulate T cell response within the liver microenvironment.However,little is known regarding the regulatory pathways involved in viral antigen presentation in HBV-infected hepatocytes.This study investigated the underlying mechanism of antigen assembly and the HBV antigen-presenting function of major histocompatibility complex(MHC)class I molecules using heat shock protein gp96.Methods:First,western blotting,flow cytometry,co-immuno precipitation,GST pull-down,and confocal microscopic assays were performed to determine whether endogenous gp96 affects MHC-I levels via an antigen presentation pathway.Second,the B3Z assay and an AAV/HBV-infected hepatocyte-specific gp96-deficient mouse model were used to determine whether gp96 knockout functionally impaired peptide cross-presentation and produced a weakened antiviral cytotoxic T cell(CTL)response both in vivo and in vitro.Finally,confocal microscopic analysis and the B3Z assay were employed to show that exogenous gp96-associated peptide was present in MHC-I molecules via the endoplasmic reticulum(ER)-Golgi secretory pathway.Results:Compared with the control,gp96 knockdown significantly reduced the cell surface levels of MHC-I by approximately 75%(P<0.01).Endogenous gp96 interacts with MHC-I and is involved in antigen presentation.Moreover,a weakened antiviral CTL response(34%compared to control mice)has been observed in hepatocyte-specific gp96-deficient mice following HBV infection.gp96 directed exogenous antigen to the ER,and the exogenous gp96-chaperoned peptide was endosome-and proteasome-dependent but not transporter associated with antigen processing dependent.Conclusions:Cellular gp96 promotes the assembly and antigen presentation of MHC class I molecules.In addition,extracellular gp96 served as a natural adjuvant to induce a CTL response in a concerted and regulated manner within different cellular compartments.Our results elucidate the mech

关键词： Hepatitis B virus Antigen cross-presentation Cytotoxic T-cell gp96

强对流天气过程特征分析及对农业生产的影响与建议

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安徽农学通报 2024年第13期30卷 103-107页

作者：蒋姗姗徐玉秀张璇通辽市气象局内蒙古通辽028000 锦州市气象局辽宁锦州121001 辽宁省气象台辽宁沈阳110000

为探究强对流天气发生机理,更好地为农业生产提供气象服务,本文利用气象信息综合处理系统实况资料、自动站加密观测资料、MICAPS4平台资料、卫星和雷达资料,对2023年7月7日辽宁锦州地区的一次强对流过程的环流形势、对流不稳定条件、卫... 详细信息

为探究强对流天气发生机理,更好地为农业生产提供气象服务,本文利用气象信息综合处理系统实况资料、自动站加密观测资料、MICAPS4平台资料、卫星和雷达资料,对2023年7月7日辽宁锦州地区的一次强对流过程的环流形势、对流不稳定条件、卫星和雷达特征进行分析。结果表明,此次过程是发生在东北冷涡天气背景下的强对流天气,高空东北冷涡加强,地面华北低压向东北移动,槽后冷空气补充,冷暖空气交绥,且垂直风切变较强,低层高湿高能环境为此次强对流提供充足的水汽和能量,促使出现了雷暴大风和短时强降水天气。同时,充分利用气象部门发布的农业气象灾害风险评估产品、预报预测产品,以应对强对流天气对农业生产的影响,做好低洼地带农田防护与排涝工作,做好病虫害防治措施。

关键词：东北冷涡短时强降水雷暴大风雷达回波

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锦州地区暴雨预警信号发布技巧研究

现代农业科技 2024年第2期 128-131页

作者：曲梓祎常姝婷姜文梁婉璐徐玉秀温舟锦州市气象局辽宁锦州121000

本文对2019-2021年锦州地区112个气象观测站的分钟级降水数据进行了统计分析,分别计算每个时次上的12、6、3、1 h的累计降水量。假设以累计降水量20 mm为起点,每增加1 mm降水时,向上浮动5 mm的降水量区间内发布暴雨蓝色、黄色和橙色预... 详细信息

本文对2019-2021年锦州地区112个气象观测站的分钟级降水数据进行了统计分析,分别计算每个时次上的12、6、3、1 h的累计降水量。假设以累计降水量20 mm为起点,每增加1 mm降水时,向上浮动5 mm的降水量区间内发布暴雨蓝色、黄色和橙色预警信号;以50 mm为起点,每增加1 mm降水时,向上浮动5 mm的降水量区间内发布暴雨红色预警信号。计算每个累计降水量区间内的平均TS评分方法所得分数、提前时间以及有效性评分方法所得分数,找出各级暴雨预警信号准确率达到90%时所对应的累计降水量区间作为发布各级暴雨预警信号的最优降水量区间,以及各级暴雨预警信号有效性评分方法得分最高时所对应的累计降水量区间为该评分方法下的最优累计降水量区间。

关键词：暴雨预警信号累计降水量区间 TS评分方法有效性评分方法辽宁锦州

Revealing structure correlation between ionic liquid and metal-organic framework matrix

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Magnetic Resonance Letters 2024年第2期4卷 65-72页

作者： Ligang xu Wenda Zhang Chenjie Lou Chenxu Geng yuxiu Sun Jie Liu Yongchao Shi Huajie Luo Jipeng Fu Haiyan Zheng Mingxue Tang Center for High Pressure Science and Technology Advanced Research Beijing100193China College of Materials Science and Engineering Guilin University of TechnologyGuilin541004China State Key Laboratory of Separation Membranes and Membrane Processes School of Material Science and EngineeringTiangong UniversityTianjin300387China University of Science and Technology Beijing Beijing100083China Key Laboratory of Rare Earth Optoelectronic Materials and Devices of Zhejiang Province Institute of Optoelectronic Materials and DevicesChina Jiliang UniversityHangzhou310018China

Solid-state batteries are rising rapidly in response to the fast-increasing energy demand.Metal-organic framework(MOF) loaded with ionic liquids has brought new opportunities for solid-state batteries owing to its good interfacial compatibility and high ionic conductivity. MOF-808 is selected to be filled with Li-contained ionic liquid for structure and ion dynamics investigation using nuclear magnetic resonance(NMR) and X-ray diffraction.This study finds that the introduced ionic liquid would partially soften the matrix of MOF-808 and thus yield amorphous phase. By selective isotope replacement under cycling symmetric ^(6)Li metal cell, Li^(+)ion is observed to mainly go cross ionic liquid in the open channel of matrix under potential polarization.

关键词： Nuclear magnetic resonance Solid-state batteries MOF-808 Ionic liquid Local structure

Molecular mechanism of dehydrin in response to environmental stress in plant

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Progress in Natural Science:Materials International 2007年第3期17卷 237-246页

作者： ZHANG yuxiu , WANG Zi and xu Jin (Department of Bioengineering, School of Chemical and Environmental Engineering, China University of Mining and Technology (Beijing), Beijing 100083, China Department of Biology, Graduate University of Chinese Academy of Sciences, Beijing 100049, China) Department of Bioengineering School of Chemical and Environmental Engineering China University of Mining and Technology (Beijing) Beijing 100083 China Department of Biology Graduate University Chinese Academy of Sciences Beijing 100049 China

Dehydrins, known as the D-11 subgroup of late embryogenesis abundant (LEA) protein, are an immunologically distinct family of proteins, which typically accumulate in desiccation-tolerant seed embryo or in vegetative tissues in response to various environmental stresses such as drought, salinity and freezing. The existence of conservative sequences designated as K, S, and Y segments is a structural feature of dehydrins, and the K segment found in all dehydrins represents a highly conserved 15 amino acid motif (EKKGIMDKIKEKLPG) and forms an amphiphilicα-helix. According to the arrangement of these domains and clustering analysis, dehydrins are subdivided into 5 subtypes: YnSK, Kn, KnS, SKn and YnK. Different types of dehydrins are induced by different environmental stress in plants. Study results showed that dehydrins might play important protective roles under abiotic stress via a number of different mechanisms, including improving or protecting enzyme activities by the cryoprotective activity in responding to freeze/thaw or dehydration; stabilizing vesicles or other endomembrane structures by function as the membrane stabilizer during freeze induced dehydration, and preventing the membrane system from the oxidative damage induced by reactive oxygen radicals as the radical scavenger. Here, the gene expression and molecular mechanisms of dehydrin in response to stress in plants are discussed.

关键词： dehydrin stress mechanism.

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齿轮传动系统中行星轮断齿故障特征分析

振动与冲击 2016年第21期35卷 81-86页

作者：王鑫徐玉秀武宝林天津工业大学机械工程学院天津300387 现代机电装备技术重点实验室天津300387

为识别齿轮传动系统中行星轮断齿故障特征及其连带的故障本质特征,建立了2级定轴齿轮+1级行星轮的风电齿轮传动系统量纲-动力学方程。对比研究正常与行星轮断齿故障状态下系统随激励频率变化的故障特性。通过研究发现了行星轮断齿故障... 详细信息

为识别齿轮传动系统中行星轮断齿故障特征及其连带的故障本质特征,建立了2级定轴齿轮+1级行星轮的风电齿轮传动系统量纲-动力学方程。对比研究正常与行星轮断齿故障状态下系统随激励频率变化的故障特性。通过研究发现了行星轮断齿故障引发的脱齿-碰撞现象,断齿故障特征及连带故障特征。依据仿真结果识别出实验信号中无法确定的由行星轮断齿故障引起的连带故障信号,诊断出故障特征表现微弱的行星轮断齿故障。

关键词：行星齿轮传动非线性动力学系统分岔断齿故障连带故障特征

基于模态应变能变化率的大型风力发电机叶片损伤识别与定位

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太阳能学报 2015年第9期36卷 2251-2256页

作者：李雅峰徐玉秀天津工业大学机械工程学院天津300387 天津工业大学现代机电装备技术天津市重点实验室天津300387

基于模态分析理论推导风力机单叶片结构的单元模态应变能变化率计算模型,使用有限元软件ANSYS建立某风场运行的1.5 MW风力发电机单叶片有限元模型,对叶片结构进行模态分析选择4个危险截面设置损伤单元,分8种不同损伤工况研究叶片的低阶... 详细信息

基于模态分析理论推导风力机单叶片结构的单元模态应变能变化率计算模型,使用有限元软件ANSYS建立某风场运行的1.5 MW风力发电机单叶片有限元模型,对叶片结构进行模态分析选择4个危险截面设置损伤单元,分8种不同损伤工况研究叶片的低阶模态频率以及模态应变能变化率,以模态应变能变化率作为表征叶片结构损伤的标识量,利用单元模态应变能变化率计算模型得到叶片在不同损伤位置与不同损伤程度下的损伤辨识结果。结果表明对于叶片位置和程度损伤的评估准确有效,可作为进一步研究和实现运行监测的方法。

关键词：风力发电机叶片应变能变化率有限元分析损伤位置

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基于信号传播模型的行星齿轮缺齿故障识别

仪器仪表学报 2016年第2期37卷 249-255页

作者：熊一奇徐玉秀天津工业大学机械工程学院天津300387 现代机电装备技术重点实验室天津300387

为了研究行星齿轮缺齿时包含微弱故障特征的振动信号在多级齿轮箱系统中的传递特性,先考虑仅由齿轮及转轴构成的"局部系统",采用集中质量法建立齿轮系统扭转动力学模型,依达朗伯原理导出振动微分方程组并求得各级齿轮啮合的振动响应即... 详细信息

为了研究行星齿轮缺齿时包含微弱故障特征的振动信号在多级齿轮箱系统中的传递特性,先考虑仅由齿轮及转轴构成的"局部系统",采用集中质量法建立齿轮系统扭转动力学模型,依达朗伯原理导出振动微分方程组并求得各级齿轮啮合的振动响应即振动源信号。为了找出振动源信号在整个系统中的传递关系,在上述动力学模型的基础上再考虑包括齿轮箱箱体在内的"整体系统",通过对信号动态传播路径的分析,针对不同测点反映故障的敏感度不同的现象,根据系统辨识理论建立信号传播模型,并运用最小二乘类方法得到振动源信号传至不同测点的传递函数估计,即找到信号在系统中的传递关系。通过分析比较传递函数幅频特性曲线进而选取合适测点,在此测点下行星齿轮缺齿故障特征频率相对明显易识别。

关键词：行星齿轮传动系统信号传播模型传递函数估计故障识别

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模糊数学在故障诊断系统中的应用研究

高压电器 2000年第5期36卷 19-21,39页

作者：徐玉秀原培新沈阳工业大学沈阳110023 邢钢东北大学沈阳110023

将模糊数学理论应用到电机故障诊断系统中 ,建立了模糊识别系统 ;根据模糊数学理论公式确定电机隶属函数的大小 ;计算出症候群对各种故障的隶属度 ;然后按隶属度对故障进行归类 ,较好地解决了不确定因素对电机产生的影响 ,诊断效果较好。

关键词：模糊数学故障诊断电机