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Factors Associated with SARS-CoV-2 Repeat Positivity—Beijing,China,June–September 2020

China CDC weekly 2022年第5期4卷 88-95,I0006-I0010页

作者： Siqi Li Xiaoli wang Li Li Yang Pan Siyuan Yang Dawei Tan Ying Shen Peng Yang Naor Bar-Zeev Yaling Hu Jacky MJennings Simin Li linghang wang Quanyi wang Beijing Center for Disease Prevention and Control BeijingChina Department of International Health Johns Hopkins Bloomberg School of Public HealthBaltimoreMDUSA Beijing Municipal Key Laboratory of Clinical Epidemiology BeijingChina School of Public Health Capital Medical UniversityBeijingChina Emergency department of Infectious diseases Beijing Ditan HospitalCapital Medical UniversityBeijingChina Laboratory of Infectious Diseases Center of Beijing Ditan Hospital Capital Medical UniversityBeijingChina Sinovac Biotech Co LtdBeijingChina Department of Pediatrics Johns Hopkins School of MedicineBaltimoreMDUSA Yiducloud(Beijing)Technology Co. LtdBeijingChina

Introduction:Repeat positive severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)following COVID-19 initial viral clearance(repositivity)poses a public health management challenge.The objective was to determine factors associated with neutralizing antibody(Nab)level and re-positivity among patients infected with a single strain SARS-CoV-2.Methods:During a single strain SARS-CoV-2 cluster in Beijing,China,longitudinal individual clinical,virological,and immunological data were collected from 368 infections from June 13 to September 22,2020.Factors associated with Nab level and re-positivity were analyzed using generalized estimating equations.Results:A total of 353(96%)SARS-CoV-2 infections had demographic,clinical,and laboratory data available.Among the 353 infections,55(15.5%)were re-positive,and blood draws were taken from 346 individuals(98.0%)during hospitalization and/or during the follow-up period.Symptoms were milder for the second-time admission for the re-positives,although 36.4%of re-positives presented with radiographic appearance of pneumonia manifestation.Compared to non-re-positive patients,NAb titers were lower among re-positives;NAb was positively associated with clinical severity.Samples from the lower respiratory tract manifested higher viral load than that from the upper respiratory tract.Multivariable analysis showed re-positivity was positively associated with being female[odd ratio(OR)=1.7,95%confidence interval(CI)1.1–2.8]and being aged<18 years(OR=5.2,95%CI 1.5–18.1);having initially asymptomatic infection(OR=13.7,95%CI 1.6–116.3);and negatively associated with a higher NAb level(OR=0.9,95%CI 0.5–1.7).Conclusions:NAb may be important for sustained viral clearance.Lower respiratory tract infection was associated with higher viral load among all infections when compared to upper respiratory tract infection.Continuous lower respiratory and intermittent upper respiratory viral shedding among COVID-19 infections may occur.

关键词： sustained initially neutral

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Dynamic Changes of ORF1ab and N Gene Ct Values in COVID-19 Omicron Inpatients of Different Age Groups—Beijing Municipality,China,November-December 2022

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China CDC weekly 2023年第8期5卷 180-183,I0001页

作者： Qing Zhang Zhaomin Feng Yiwei Hao Lirong Wei Aibin wang Zhixing Han Meimei Tian Sheng Sun Xin'gang Li Tianjiao Xue Xiangjing Kong Baoliang Li Cheng Kou Quanyi wang Da Huo linghang wang Beijing Ditan Hospital Capital Medical UniversityBeijingChina Beijing Center for Disease Prevention and Control BeijingChina School of Public Health Capital Medical UniversityBeijingChina Beijing Municipal Key Laboratory of Clinical Epidemiology BeijingChina

Introduction:In November 2021,the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)Omicron variant was identified as the variant of concern and has since spread globally,replacing other cocirculating variants.To better understand the dynamic changes in viral load over time and the natural history of the virus infection,we analyzed the expression of the open reading frames 1ab(ORF1ab)and nucleocapsid(N)genes in patients infected with Omicron.Methods:We included patients initially admitted to the hospital for SARS-CoV-2 infection between November 5 and December 25,2022.We collected daily oropharyngeal swabs for quantitative reverse transcriptase-polymerase chain reaction tests using commercial kits.We depicted the cycle threshold(Ct)values for amplification of ORF1ab and N genes from individual patients in age-specific groups in a time series.Results:A total of 480 inpatients were included in the study,with a median age of 59 years(interquartile range,42 to 78;range,16 to 106).In the<45-year-old age group,the Ct values for ORF1ab and N gene amplification remained below 35 for 9.0 and 11.5 days,respectively.In the≥80-year-old age group,the Ct values for ORF1ab and N genes stayed below 35 for 11.5 and 15.0 days,respectively,which was the longest among all age groups.The Ct values for N gene amplification took longer to rise above 35 than those for ORF1ab gene amplification.Conclusion:The time to test negative varied among different age groups,with viral nucleic acid shedding taking longer in older age groups compared to younger age groups.As a result,the time to resolution of Omicron infection increased with increasing age.

关键词： patients admitted younger

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基于波束形成的变压器噪声成像技术研究与应用

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电气工程学报 2024年第1期19卷 290-298页

作者：袁晶卢灏刘领航王永强广东电网有限责任公司广州供电局广州510000 华北电力大学电力工程系保定071003

作为变电站中最为昂贵和重要的设备,变压器一直是科研人员的研究重点对象。目前对变压器噪声源识别的相关研究较少,因此结合波束形成技术针对变压器噪声源识别展开研究。首先根据所调研的变压器噪声特性,确定了所关注的噪声频段和所用... 详细信息

作为变电站中最为昂贵和重要的设备,变压器一直是科研人员的研究重点对象。目前对变压器噪声源识别的相关研究较少,因此结合波束形成技术针对变压器噪声源识别展开研究。首先根据所调研的变压器噪声特性,确定了所关注的噪声频段和所用的声源识别方法,阐述了宽带信号的波达方向估计与波束形成的相关理论,进而整理出了一种基于频域数据的宽带变压器信号定位思路,利用仿真结果证实了所提定位思路的合理性与准确性。最后基于LabVIEW平台搭建了一套变压器噪声源识别系统,并通过对不同情况下实际运行变压器的现场试验,对系统的定位效果进行了测试,其定位误差在2°左右,结果证明噪声源识别思路和搭建的系统平台具有良好的可靠性与可用性。

关键词：变压器波束形成空间谱估计噪声源识别

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基于小半径曲线隧道盾构施工的Peck公式修正及其工程应用

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城市轨道交通研究 2024年第4期27卷 40-43,50页

作者：杨令航中铁十四局集团隧道工程有限公司济南250013

[目的]在城市轨道交通线路规划中,因受建筑物地基、地下管道和软弱土层等因素影响,通常会选用曲线隧道乃至小半径曲线隧道。与直线隧道相比,小半径曲线隧道盾构施工加大了地面沉降失控风险。因此,需对小半径曲线隧道盾构施工中地面沉降... 详细信息

[目的]在城市轨道交通线路规划中,因受建筑物地基、地下管道和软弱土层等因素影响,通常会选用曲线隧道乃至小半径曲线隧道。与直线隧道相比,小半径曲线隧道盾构施工加大了地面沉降失控风险。因此,需对小半径曲线隧道盾构施工中地面沉降控制进行研究。[方法]通过计算曲线隧道盾构施工过程中的超挖间隙,推导出曲线段内每一环的超挖量;又通过引入地层损失率得出隧道半径与地层损失率的关系;根据现有Peck公式的适用性统计分析结果,结合基础地层损失率、总地层损失率、超挖导致额外地层损失率,以及沉降体积切片计算得出了适用于小半径曲线隧道盾构施工的修正Peck公式。以太原某地铁线路的工程实例为研究背景,将修正Peck公式计算结果与现场监测数据进行对比,验证了修正Peck公式的适用性。[结果及结论]工程实例验证结果表明,修正Peck公式对小半径曲线隧道盾构施工具有较好的适用性。

关键词：地铁盾构隧道小半径曲线地面沉降 Peck公式

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美国网络安全治理体系的现实困境

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情报杂志 2024年第5期43卷 72-79页

作者：孟令航刘帮成上海交通大学国际与公共事务学院上海200030 上海市创新政策评估研究中心上海200030

[研究目的]信息时代,网络空间的稳定与发展问题已超越单纯的技术领域,日渐上升到国家安全层面。美国作为最早构建国家层面网络安全治理体系的国家,对其开展研究具有重要意义。[研究方法]该文基于多年来有关美国网络安全治理体系的相关... 详细信息

[研究目的]信息时代,网络空间的稳定与发展问题已超越单纯的技术领域,日渐上升到国家安全层面。美国作为最早构建国家层面网络安全治理体系的国家,对其开展研究具有重要意义。[研究方法]该文基于多年来有关美国网络安全治理体系的相关官方文件、学术讨论、媒体报道等文本资料,以制度理论为基础搭建分析框架,分析了美国网络安全治理体系的现实困境。[研究结论]体制的自身特征、公私的立场差异、外部的环境形势共同构成了制约美国网络安全治理体系进一步发展的结构性因素,其深层矛盾短时间内仍难解决。

关键词：网络安全网络空间网络安全治理网络安全治理体系信息技术制度理论美国

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An Immunocompetent Patient with High Neutralizing Antibody Titers Who Shed COVID-19 Virus for 169 days——China,2020

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China CDC weekly 2021年第32期3卷 688-691,I0003-I0008页

作者： Li Li Siqi Li Yang Pan Ling Qin Siyuan Yang Dawei Tan Yaling Hu Maria Deloria Knoll Xiaoli wang linghang wang Quanyi wang Beijing Ditan Hospital Capital Medical UniversityBeijingChina Johns Hopkins Bloomberg School of Public Health BaltimoreMarylandUSA Beijing Center for Disease Control and Prevention BeijingChina Biomedical Information Center of Beijing YouAn Hospital Capital Medical UniversityBeijingChina Sinovac Biotech Co LtdBeijingChina

Few reports are available about prolonged shedding of coronavirus disease(COVID-19)virus,also known as severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),by immunocompetent patients.We report a case of an infected,immunocompetent person with 169 days of COVID-19 virus shedding during which time he had two brief periods when he tested negative for COVID-19 followed by again testing positive.We describe relevant clinical,immunological,and genomic features.We found that continuous and prolonged viral replication and infectivity existed in an immunocompetent COVID-19 patient,despite having high neutralizing antibody titers.

关键词： Antibody acute respiratory

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美国国家网络安全制度变迁的双重逻辑(1978~2021)

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美国研究 2024年第1期38卷 95-116,7页

作者：孟令航刘帮成上海交通大学国际与公共事务学院上海交通大学上海市创新政策评估研究中心

互联网诞生之时就富有浓厚的国家安全色彩,美国是世界上较早就网络安全问题进行制度化建设的国家,通过确立网络安全战略优势,以将霸权地位延伸至网络空间。数十年来,美国国家网络安全制度的发展历经早期建构、中期扩张与近期调整三个阶... 详细信息

互联网诞生之时就富有浓厚的国家安全色彩,美国是世界上较早就网络安全问题进行制度化建设的国家,通过确立网络安全战略优势,以将霸权地位延伸至网络空间。数十年来,美国国家网络安全制度的发展历经早期建构、中期扩张与近期调整三个阶段,相应的阶段性特征差异明显。传统而言,历史制度主义主要包含结构与历史两个逻辑维度,这为制度变迁的动力来源与过程机制提供了一种可能的解释。就结构逻辑来说,制度环境、利益关系与安全观念分别构成了美国国家网络安全制度产生与演变的动因。从历史逻辑来看,作为关键节点的“9·11”事件与“棱镜门”事件,打破了每个阶段路径依赖的制度惯性与均衡状态,使美国国家网络安全制度进入短暂而剧烈的断裂状态,并在三个动因的共同作用下开启制度重组,形成新的制度并进入新的稳定。美国国家网络安全制度仍将不断自我强化,以战略后退的态势持续收缩,进一步回归网络安全实力建设。

关键词：美国军事与外交网络安全制度变迁结构逻辑历史逻辑

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Rapid and accurate identification of SARS-CoV-2 variants containing E484 mutation

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The Innovation 2022年第1期3卷 17-18页

作者： Yuan Zhang Yanqiu Wei Siyuan Yang Yunlong Li Jing wang Zhaoyan Nie Yuhai Bi Wenjun Liu linghang wang Limin Yang CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyCenter for Influenza Research and Early Warning(CASCIRE)CAS-TWAS Center of Excellence for Emerging Infectious Diseases(CEEID)Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 101408China Laboratory of Infectious Diseases Center Emergency Department of Infectious DiseasesBeijing Ditan HospitalCapital Medical UniversityBeijing 100015China National Institute of Metrology Beijing 102200China The Fourth Hospital of Hebei Medical University Shijiazhuang 050011China

The ongoing coronavirus disease 2019(COVID-19)pandemic caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)infection has led to over 240 million confirmed infections and severe economic burdens worldwide.Multiple emerging SARS-CoV-2 variants of concern(VOCs)and variants of interest(VOIs)have recently beenidentifiedand are nowspreading internationally,including B.1.1.7(Alpha),B.1.351(Beta),P.1(Gamma),B.1.617(Delta and Kappa),C.37(Lambda),and B.1.621(Mu),all of which appear to bemore easily transmitted(WHO,COVID-19Weekly EpidemiologicalUpdate).Beta andGamma VOCs can seriously impair the protective efficacy of existing vaccines,potentially precluding the possibility of attaining"herd immunity."

关键词： protective acute respiratory

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Distinct durability of IgM/IgG antibody responses in COVID-19 patients with differing severity

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Science China(Life Sciences) 2022年第1期65卷 223-226页

作者： Junyan Han Ning Zhang Danying Chen Yuhuan Gong Guoli Li Yaxian Kong Lin Pu Chen Chen Jingyuan Liu Qi wang Ju Zhang Xuesen Zhao Juan Du Kai Han Chuan Song linghang wang Mingxi Hua Yu Hao Rui Song Yangzi Song Fengting Yu Siyuan Yang Haofeng Xiong Wei Zhang George F.Gao Fujie Zhang Ang Li Hui Zeng Yuhai Bi Beijing Key Laboratory of Emerging Infectious Diseases Institute of Infectious DiseasesBeijing Ditan HospitalCapital Medical UniversityBeijing 100015China CAS Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyCenter for Influenza Research andEarly-warning(CASCIRE)CAS-TWAS Center of Excellence for Emerging Infectious Diseases(CEEID)Chinese Academy of SciencesBeijing 100101China Institutes of Physical Science and Information Technology Anhui UniversityHefei 230601China Intensive Care Medicine Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Center of Liver Diseases Beijing Ditan HospitalCapital Medical UniversityBeijing 100015China Laboratory of Infectious Diseases Center of Beijing Ditan Hospital Capital Medical UniversityBeijing 100015China The Infectious Disease Diagnostic Therapeutic and Research CentersBeijing Ditan HospitalCapital Medical UniversityBeijing 100015China Clinical Center for HIV/AIDS Clinical and Research Center of Infectious DiseasesBeijing Ditan HospitalCapital Medical UniversityBeijing 100015China University of Chinese Academy of Sciences Beijing 100049China

Dear Editor,The coronavirus disease 2019(COVID-19)pandemic is generating a demand for simultaneous vaccine development,which is expected to prevent future outbreaks by eliciting sufficient and protective immunity.

关键词： protective vaccine severity

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Phylogenomic tracing of asymptomatic transmission in a COVID-19 outbreak

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The Innovation 2021年第2期2卷 150-156页

作者： Ju Zhang Nan Ding Yangzi Song Rui Song Yang Pan linghang wang Shuo Yan Qi wang Shanfang Ma Lirong Wei Fengting Yu Lianhe Lu Fujie Zhang Chen Chen Hui Zeng Beijing Ditan Hospital Capital Medical UniversityBeijing 100015China Beijing Key Laboratory of Emerging Infectious Diseases Beijing 100015China Institute for Infectious Disease and Endemic Disease Control Beijing Center for Disease Prevention and ControlBeijing 100013China These authors contributed equally

SARS-CoV-2 has caused over 100 million deaths and continues to spread rapidly around the world.Asymptomatic transmission of SARS-CoV-2 is the Achilles’heel of COVID-19 public health control measures.Phylogenomic data on SARS-CoV-2 could provide more direct information about asymptomatic transmission.In this study,using a novel MINERVA sequencing technology,we traced asymptomatic transmission of COVID-19 patients in Beijing,China.One hundred and seventy-eight close contacts were quarantined,and 14 COVID-19 patients were laboratory confirmed by RT-PCR.We provide direct phylogenomic evidence of asymptomatic transmission by constructing the median joining network in the cluster.These data could help us to determine whether the current symptom-based screening should cover asymptomatic persons.

关键词： SARS-CoV-2 COVID-19 asymptomatic transmission outbreak phylogenomic

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