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Transmission models of tuberculosis in heterogeneous population

Chinese Medical Journal 2007年第15期120卷 1360-1365页

作者： JIA Zhong-wei LI Xiao-wen FENG Dan cao wu-chun School of InformatioEineering Beijing University of Posts and Telecommunications Beijing 100876 China Beijing Institute of Microbiology and Epidemiology State Key Laborary of Pathogen and Biosecurity Beijing 100071 China Institute of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China

Objective To review the transmission models of tuberculosis in heterogeneous population. Data sources The data used in this review were adopted mainly from the studies of models of tuberculosis reported from 1995 to 2006. Study selection Relevant literature on transmission models of tuberculosis in heterogeneous populations are referenced. Results Casual/random factors and genetic factors are the main reasons for epidemics of tuberculosis in recent years. Mass public transport is playing the primary role in casually close contact which can facilitate the transmission of tuberculosis. Genetic susceptibility not only varies endemic prevalence levels, but also drastically alters the effects of treatment for tuberculosis patients. Detailed studies further exhibit that casual contact and genetic factor are responsible for over 30%-40% of the total new cases in recent years. The prevalence of tuberculosis could double （from 33% to 60%） if a genetically susceptible phenotype is present in only 30% of the population. And some challenges have emerged along with these exciting results. Conclusions Casual/random contact, public transport and genetic susceptibility are responsible for most new tuberculosis cases and a wide variation in endemic tuberculosis levels between regions. Hence, the transmission model of tuberculosis in a heterogeneous population can provide more clues to underlying mechanism of tuberculosis transmission than in a homogeneous population. However, many challenges remain for us in understanding transmission of disease.

关键词： tuberculosis transmission basic reproductive number mathematical mode heterogeneous

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Association between the incidence of typhoid and paratyphoid fever and meteorological variables in Guizhou, China

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Chinese Medical Journal 2012年第3期125卷 455-460页

作者： Wang Lu-xi Li Xiu-jun Fang Li-qun Wang Duo-chun cao wu-chun Kan Biao Beijing Inst Microbiol & Epidemiol State Key Lab Pathogen & Biosecur Beijing 100071 Peoples R China Chinese Ctr Dis Control & Prevent Natl Inst Communicable Dis Control & Prevent State Key Lab Infect Dis Prevent & Control Beijing 102206 Peoples R China Shandong Univ Sch Publ Hlth Jinan 250012 Shandong Peoples R China Changping Dist Ctr Dis Control & Prevent Beijing 102200 Peoples R China

Background Typhoid/paratyphoid fever （TPF） is endemic in *** conducted wavelet analysis and Spearman＇s rank correlation analysis to explore the impact of meteorological variations on TPF infection in Guizhou,in an attempt to assess the risk factors associated with TPF *** We examined the association between TPF incidence in Guizhou and temperature,precipitation and relative humidity using 24 years of data from 1984 to *** of TPF incidence and the impact of climate factors on the TPF were detected by Spearman＇s rank correlation and wavelet analysis,Results Temperature and precipitation with a 1-month lag were positively correlated with the monthly incidence of *** multiyear incidence pattern of TPF in Guizhou was explicitly ***,the association and driving effect of precipitation on TPF were observed,and the results showed that the incidence of TPF in Guizhou had a closer correlation with precipitation than with *** Safe water supply is the key issue for TPF control in ***,climate variation might impact the enteric infections,which may inform policy assessment for TPF control in Guizhou.

关键词： typhoid/paratyphoid fever meteorological variables

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Resilience-incorporated seismic risk assessment of precast concrete frames with“dry”connections

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 403-425页

作者： wu Chenhao Tang Yuchuan cao Xuyang wu Gang Key Laboratory of Concrete and Prestressed Concrete Structures of the Ministry of Education Nanjing 211102China Department of Civil and Environmental Engineering University of CaliforniaLos AngelesCA 90095USA School of Civil Engineering Southeast UniversityNanjing 211102China College of Civil and Transportation Engineering Hohai UniversityNanjing 210024China

A resilience-incorporated risk assessment framework is proposed and demonstrated in this study to manifest the advantageous seismic resilience of precast concrete frame(PCF)structures with“dry”connections in terms of their low damage and rapid *** framework integrates various uncertainties in the seismic hazard,fragility,capacity,demand,loss functions,and post-earthquake *** this study,the PCF structures are distinguished from ordinary reinforced concrete frame(RCF)structures by characterizing multiple limit states for the PCF based on its unique damage ***,probabilistic story-wise pushover analyses are performed to yield story-wise capacities for the predefined limit *** the seismic resilience analysis,a step-wise recovery model is proposed to idealize the functionality recovery process,with separate considerations of the repair and non-repair *** recovery model leverages the economic loss and downtime to delineate the stochastic post-earthquake recovery curves for the resilience loss *** such,contingencies in the probabilistic post-earthquake repairs are incorporated and the empirical judgments on the recovery parameters are largely *** proposed framework is demonstrated through a comparative study between two“dry”connected PCFs and one RCF designed as alternative structural systems for a prototype *** results from the risk quantification indicate that the PCFs show reduced loss hazards and lower expected losses relative to the ***,the PCF equipped with energy dissipation devices at the“dry”connections largely reduces the expected economic loss,downtime,and resilience loss by 29%,56%,and 60%,respectively,compared to the RCF.

关键词： precast concrete frame non-emulative precast system seismic resilience seismic risk functional recovery

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The Method of Polynomial Particular Solutions for Solving Nonlinear Poisson-Type Equations

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Acta Mechanica Solida Sinica 2024年第1期37卷 155-165页

作者： Zhile Jia Yanhua cao Xiaoran wu School of Sciences East China Jiaotong UniversityNanchang 330013China

In this paper,the method of polynomial particular solutions is used to solve nonlinear Poisson-type partial differential equations in one,two,and three *** condition number of the coefficient matrix is reduced through the implementation of multiple scale technique,ultimately yielding a stable numerical *** methodological process can be divided into two main parts:first,identifying the corresponding polynomial particular solutions for the linear differential operator terms in the governing equations,and second,employing these polynomial particular solutions as basis function to iteratively solve the remaining nonlinear terms within the governing ***,we investigate the potential improvement in numerical accuracy for equations with singularities in the analytical solution by shifting the computational domain a certain *** experiments are conducted to assess both the accuracy and stability of the proposed method.A comparison of the obtained results with those produced by other numerical methods demonstrates the accuracy,stability,and efficiency of the proposed method in handling nonlinear Poisson-type partial differential equations.

关键词： Nonlinear equation Singularity Polynomial particular solutions Poisson type

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Effect of stress-relief annealing on thermal fatigue cracks for die-casting die steels

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Journal of Iron and Steel Research International 2024年第5期31卷 1164-1176页

作者： Zhi-xiong Bai Xiao-chun wu School of Materials Science and Engineering Shanghai UniversityShanghai200444China

The effect of stress-relief annealing at different stages of thermal fatigue tests on crack growth was investigated using a self-built thermal cycle *** results showed that annealing could limit crack expansion *** reduced dislocation density and released the accumulation of residual *** addition,the strain accumulation in carbides was reduced by this *** was also found that double annealing was even more effective at inhibiting crack expansion compared to single stress-relief *** 1000 cycles,the maximum crack length was reduced by 31.1%and 45.2%for the samples after using the optimal single and double annealing processes,*** single stress-relief annealing,earlier annealing provides more benefit in delaying crack ***,effective double stress-relief annealing requires a suitable time interval between the annealing ***,after 800 cycles,surface hardness decreased significantly accompanied by an increase in the size and number of carbides,and cracks expanded predominantly along grain boundaries.

关键词： Thermal fatigue Steel Carbide Stress-relief annealing Dislocation Residual stress

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Isolation and characterization of dengue virus serotype 2 from the large dengue outbreak in Guangdong, China in 2014

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Science China(Life Sciences) 2014年第12期57卷 1149-1155页

作者： ZHAO Hui ZHAO Ling Zhai JIANG Tao LI Xiao Feng FAN Hang HONG Wen Xin ZHANG Yu ZHU Qin YE Qing TONG Yi Gang cao wu chun ZHANG Fu chun QIN Cheng Feng State Key Laboratory of Pathogen and Biosecurity Beijing Institute of Microbiology and Epidemiology Guangzhou 8th People's Hospital Guangzhou Medical University

Dengue has been well recognized as a global public health threat,but only sporadic epidemics and imported cases were reported in recent decades in *** July 2014,an unexpected large dengue outbreak has occurred in Guangdong province,China,resulting in more than 40000 patients including six *** clarify and characterize the causative agent of this outbreak,the acute phase serum from a patient diagnosed with severe dengue was subjected to virus isolation and high-throughput sequencing(HTS).Traditional real-time RT-PCR and HTS with Ion Torrent PGM detected the presence of dengue virus serotype 2(DENV-2).A clinical DENV-2 isolate GZ05/2014 was obtained by culturing the patient serum in mosquito C6/36 *** complete genome of GZ05/2014 was determined and deposited in Gen Bank under the access number *** analysis based on the complete envelope gene showed that the newly DENV-2 isolate belonged to Cosmopolitan genotype and clustered closely with other Guangdong strains isolated in the past *** amino acid mutations that are obviously known to increase virulence or replication were identified throughout the genome of GZ05/*** high homology of Guangdong DENV-2 strains indicated the possibility of establishment of local DENV-2 circulation in Guangdong,*** results help clarify the origin of this epidemic and predict the future status of dengue in China.

关键词： dengue virus serotype 2 virus isolation phylogenetic analysis envelope gene

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贵州省罗甸县山羊体表寄生蜱携带柯克斯体属细菌的基因特征分析

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中国媒介生物学及控制杂志 2024年第4期35卷 417-421页

作者：陈秋何贤海孟娇吴胜春唐继霞林祉君余福勋江佳富孙毅曹务春詹琳周远忠遵义医科大学公共卫生学院贵州遵义563006 德江县农业农村局动物疫病预防控制中心贵州铜仁565299 贵州医科大学公共卫生与健康学院环境污染与疾病监控教育部重点实验室贵州贵阳550025 贵州大学贵州贵阳550025 国家卫生健康委肺脏免疫性疾病诊治重点实验室(贵州省人民医院) 贵州贵阳550002 军事科学院军事医学研究院北京100001 贵州省高等学校孕妇儿童健康与暴露科学重点实验室贵州遵义563006

目的了解山羊体表寄生蜱携带的柯克斯体属细菌的基本特点。方法采集贵州省罗甸县山区散养山羊体表寄生蜱,单只提取蜱DNA,制备混合DNA样品进行细菌16S rRNA扩增子高通量测序。同时对个体蜱DNA样本进行柯克斯体属特异引物聚合酶链式反应检... 详细信息

目的了解山羊体表寄生蜱携带的柯克斯体属细菌的基本特点。方法采集贵州省罗甸县山区散养山羊体表寄生蜱,单只提取蜱DNA,制备混合DNA样品进行细菌16S rRNA扩增子高通量测序。同时对个体蜱DNA样本进行柯克斯体属特异引物聚合酶链式反应检测,结合DNA测序验证高通量测序的结果。结果共采集66只蜱,其中63只为长角血蜱,3只为微小扇头蜱。通过高通量测序获得柯克斯体共生菌序列17条,采用柯克斯体属16S rRNA基因PCR扩增对单只蜱样本进行鉴定,电泳阳性率为28.78%(19/66)。遗传进化分析提示本研究发现的柯克斯体共生体与以色列株(JQ480818)和泰国株(KC170759)在同一分支。结论贵州罗甸县散养山羊体表寄生蜱中柯克斯体共生菌携带率较高,其致病性及公共卫生意义还待进一步研究。

关键词：蜱柯克斯体属高通量测序贵州

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Experimental and Numerical Investigation of Non-synchronous Blade Vibration Excitation in a Transonic Axial Compressor

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Journal of Thermal Science 2024年第2期33卷 602-610页

作者： WANG Songbai wu Yadong CHEN Yong cao Zhipeng School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai200240China AECC Sichuan Gas Turbine Establishment Chengdu610500China

The complex flow phenomenon of rotating instability(RI) and its induced non-synchronous vibration(NSV) have become a significant challenge as they continuously increase aerodynamic *** study aims to provide an understanding of the non-synchronous blade vibration phenomenon caused by the rotating instability of a transonic axial compressor *** this case,blade vibrations and non-synchronous excitation are captured by strain gauges and unsteady wall pressure transducer *** numerical simulations for a full-annulus configuration are used to obtain the non-synchronous flow *** results show that the first-stage rotor blade exhibits an NSV close to the first bending mode;NSV is accompanied by a sharp increase in pressure pulsation;amplitude can reach 20%,and unsteady aerodynamic frequency will lock in a structural mode frequency when the blade vibrates in a large-amplitude *** predicted NSV frequency aligns well with the experimental *** dominant mode of circumferential instability flow structure is approximately 47% of the number blades,and the cell size occupies 2-3 pitches in the circumferential *** full-annulus unsteady simulations demonstrate that the streamwise oscillation of the shedding and reattachment vortex structure is the main cause of NSV owing to the strong interaction between the tip leakage and separation vortices near the suction surface.

关键词： non-synchronous vibration transonic axial compressor rotor blade rotating instabilities unsteady flow

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Ultrafast optical modulation of the fluorescence from a single-photon emitter in silicon carbide

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Photonics Research 2024年第5期12卷 941-946页

作者： MENGTING HE YUJING cao JUNJIE LIN ZHIPING JU BOTAO wu E wu State Key Laboratory of Precision Spectroscopy East China Normal UniversityShanghai 200241China Photon Technology(Zhejiang)Co. Ltd.Jiaxing 314100China National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200000China Department of Physics and Shanghai Key Laboratory for Magnetic Resonance East China Normal UniversityShanghai 200241China Chongqing Key Laboratory of Precision Optics Chongqing Institute of East China Normal UniversityChongqing 401120China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan 030006China

The quest for the room-temperature optical transistor based on nonlinearities in single atoms or molecules is attracting a lot of *** this work,a single-photon emitter in cubic silicon carbide is verified that can operate as an optical switch at room temperature under pulsed green laser illumination with a near-infrared pulsed laser as the control *** demonstrated an ultrafast and reversible optical modulation with a high photoluminescence intensity suppression ratio up to 97.9%and a response time as short as 287.9±5.7 *** current development provides insights for high-precision and ultrafast optical switches,with possibilities for integration with emerging electronic installations to realize more intelligent photoelectric integrated devices.

关键词： emitter carbide photon

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A Novel CCA-NMF Whitening Method for Practical Machine Learning Based Underwater Direction of Arrival Estimation

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Journal of Beijing Institute of Technology 2024年第2期33卷 163-174页

作者： Yun wu Xinting Li Zhimin cao School of Physics and Electronic Engineering Northeast Petroleum UniversityDaqing 163318China

Underwater direction of arrival(DOA)estimation has always been a very challenging theoretical and practical *** to the serious non-stationary,non-linear,and non-Gaussian characteristics,machine learning based DOA estimation methods trained on simulated Gaussian noised array data cannot be directly applied to actual underwater DOA estimation *** order to deal with this problem,environmental data with no target echoes can be employed to analyze the non-Gaussian ***,the obtained information about non-Gaussian components can be used to whiten the array *** on these considerations,a novel practical sonar array whitening method was ***,based on a weak assumption that the non-Gaussian components in adjacent patches with and without target echoes are almost the same,canonical cor-relation analysis(CCA)and non-negative matrix factorization(NMF)techniques are employed for whitening the array *** the whitened array data,machine learning based DOA estimation models trained on simulated Gaussian noised datasets can be used to perform underwater DOA estimation *** results illustrated that,using actual underwater datasets for testing with known machine learning based DOA estimation models,accurate and robust DOA estimation performance can be achieved by using the proposed whitening method in different underwater con-ditions.

关键词： direction of arrival(DOA) sonar array data underwater disturbance machine learn-ing canonical correlation analysis(CCA) non-negative matrix factorization(NMF)

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