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Perturbed low-thrust geostationary orbit transfer guidance via polynomial costate estimation

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Chinese Journal of Aeronautics 2024年第3期37卷 181-193页

作者： Zhao LI Hengnian LI Fanghua JIANG Junfeng LI State Key Laboratory of Astronautic Dynamics Xi’an Satellite Control CenterXi’an 710043China School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

This paper proposes an optimal,robust,and efficient guidance scheme for the perturbed minimum-time low-thrust transfer toward the geostationary *** Earth’s oblateness perturbation and shadow are taken into *** is difficult for a Lyapunov-based or trajectory-tracking guidance method to possess multiple characteristics at the same time,including high guidance optimality,robustness,and onboard computational *** this work,a concise relationship between the minimum-time transfer problem with orbital averaging and its optimal solution is identified,which reveals that the five averaged initial costates that dominate the optimal thrust direction can be approximately determined by only four initial modified equinoctial orbit elements after a coordinate *** on this relationship,the optimal averaged trajectories constituting the training dataset are randomly generated around a nominal averaged *** polynomial regression models are trained on the training dataset and are regarded as the costate *** the transfer,the spacecraft can obtain the real-time approximate optimal thrust direction by combining the costate estimations provided by the estimators with the current state at any ***,all these computations onboard are *** simulation results show that the proposed guidance scheme possesses extremely high guidance optimality,robustness,and onboard computational efficiency.

关键词： Low thrust Orbital transfer Trajectory optimization Guidance Indirect method Orbital averaging Machine learning Geostationary satellites

Acceptance and Factors Associated With Participation in Functional Cure–Related Trials Among People Living With HIV: A Cross-sectional Study in Southern China

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Infectious Microbes & Diseases 2024年第1期6卷 11-19页

作者： Zhaomin Deng Minjuan Shi Yue Yuan GuangjinCao Chunyan Wen Lijuan Chen Xueying Fan Linan Wu Jianhui Yuan Huachun Zou Linghua Li Caijun Sun School of Public Health(Shenzhen) Shenzhen Campus of Sun Yat-sen UniversityShenzhenChina Department of Diseases control Panyu District Center for Disease Control and PreventionGuangzhouChina Infectious Disease center Guangzhou Eighth People's HospitalGuangzhou Medical UniversityGuangzhouChina Nanshan District center for Disease {1. and Prevention ShenzhenChina Key Laboratory of Tropical Disease control(Sun Yat-sen University) Ministry of EducationGuangzhouChina

HIV remains a global health challenge,and research efforts directed towards a functional cure require people living with HIV(PLHIV)in-volvement in clinical *** study assessed willingness to participate in HIV functional cure–related clinical trials and associated factors among PLHIV in Guangzhou,China,using a questionnaire survey *** analyzed responses from 71. questionnaires,finding that 71.2%were willing to participate in Phase Ⅲtrials,while 51.7%were willing to participate in Phase I trials and 42.9%expressed acceptability for analytic treatment *** logistic regression demonstrated that male PLHIV,those with awareness of functional cure,and PLHIV,who had been on antiretroviral therapy(ART)for less than 1.year,were more willing to partic-ipate in Phase Ⅲ*** with a body mass index greater than 24,and those without resistance to ART drug were more willing to participate in Phase I *** major motivations for participation in Phase Ⅲtrials were access to cutting-edge treatments(62.6%)and supporting research(55.3%).Safety was the main concern contributing to *** study revealed a high willingness to participate in HIV functional cure–related trials among PLHIV in Guangzhou,China,and willingness varied across different trial phases and was influenced by multiple *** study provides valuable references for future clinical trial recruitment strategies and public health policy formulation.

关键词： people living with HIV functional cure clinical trials willingness

Prevalence and Genomic Characterization of Multidrug-Resistant Salmonella enterica Serovar Kentucky Sequence Type 1.8 Circulating—Beijing Municipality,China,201.–2023

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China CDC weekly 2024年第33期6卷 825-833页

作者： Mei Qu Ying Huang Bing Lyu Xin Zhang Yi Tian Zhaomin Feng Zhiyong Gao Daitao Zhang Beijing Key Laboratory of Diagnostic and Traceability Technologies for Food Poisoning Beijing Center for Disease Prevention and ControlBeijingChina

Introduction Highly fluoroquinolone-resistant Salmonella enterica serovar Kentucky(***)of sequence type(ST)1.8 has emerged as a global multidrug-resistant(MDR)clone,posing a threat to public *** Whole genome sequencing and antibiotic susceptibility testing was used to characterize the population structure and evolutionary history of 54 *** isolates recovered from food and human clinical cases in Beijing from 201. to *** All 54 *** ST1.8 isolates exhibited resistance to quinolones,carrying point mutations in the quinolone resistance-determining regions(gyrA_S83F and parC_S80I).Resistance to other antibiotics(folate pathway inhibitors,cephems,aminoglycosides,phenicols,rifamycin,fosfomycin,macrolides,and tetracyclines),mediated by the sul1.sul2,dfrA1.,blaCTX-M,blaTEM-1.,aac(3)-Id,aadA2,aadA7,aph(3')-I,aph(3'')-Ib,rmtB,floR,arr-2,fosA,mph(A),and tet(A)genes,was also observed in different *** Beijing *** ST1.8 evolutionary tree was divided into clades 1.8.2-1.and 1.8.2-2,which were further differentiated into three subclades:1.8.2-2A,1.8.2-2B,and *** with the extended-spectrumβ-lactamase-encoding gene blaCTX-M-1.b in 1.8.2-1.the co-existence of blaCTX-M-55 and blaTEM-1.,as well as chromosomally located qnrS1.was detected in most 1.8.2-2 isolates,which showed more complex MDR *** ST1.8 outbreak isolates derived from two predominant clonal sources:1.8.2-1.with cgST236434 and 1.8.2-2A with *** The *** population in Beijing is genetically diverse,consisting of multiple co-circulating lineages that have persisted since *** surveillance of food and humans will aid in implementing measures to prevent and control the spread of AMR.

关键词： Kentucky predominant Whole

Comparative Effectiveness of Mobile Health-Based Comprehensive Smoking Cessation Modalities and Traditional Clinic-Delivered Treatments—Beijing Municipality,China,May 2022 to April 2024

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China CDC weekly 2024年第22期6卷 516-521页

作者： Shuilian Chu Hang Jing Di Zhang Yuan Cao Yunliang Qian Xiurong Liu Lin Xiao Zhaohui Tong Lirong Liang Department of Research on Tobacco Dependence Therapies Beijing Institute of Respiratory Medicine and Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina Beijing center for Disease Prevention and {1. BeijingChina Tobacco control Office Chinese Center for Disease Control and PreventionBeijingChina Department of Respiratory and Critical Care Medicine Beijing Institute of Respiratory Medicine and Beijing Chao-Yang HospitalCapital Medical UniversityBeijingChina

What is already known about this topic?Most Chinese smokers have not accessed professional help due to a lack of sufficient smoking cessation *** health(mHealth)can mitigate obstacles related to time and transportation,thereby providing effective support for smokers seeking to *** is added by this report?This study offers real-world evidence supporting the effectiveness of mHealth-based comprehensive smoking cessation *** findings indicate that these modalities can significantly enhance abstinence rates,albeit to a lesser extent compared to traditional clinicbased *** to the intervention was identified as a critical factor influencing the effectiveness of smoking cessation *** are the implications for public health practice?The mHealth-based comprehensive smoking cessation modalities,with or without mailing cessation medications,present a promising approach to enhancing access to and utilization of smoking cessation *** strategy addresses the significant challenge of limited smoking cessation resources in China.

关键词： smoke Health thereby

Numerical simulation on Radon Retardation Behavior of Covering Floats in Radon-Containing Water

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Biomedical and Environmental Sciences 2024年第4期37卷 406-417页

作者： LIU Shu Yuan ZHANG Li YE Yong Jun DING Ku Ke National Institute for Radiological Protection Chinese Center for Disease Control and PreventionBeijing 100088China Office for Public Health Management Chinese Center for Disease Control and PreventionBeijing 102206China Key Discipline Laboratory for National Defense for Biotechnology in Uranium Mining and Hydrometallurgy University of South ChinaHengyang 421001HunanChina

Objective This study aimed to efficiently reduce the release of radon from water bodies to protect the *** Based on the sizes of the experimental setup and modular float,computational fluid dynamics(CFD)was used to assess the impact of the area coverage rate,immersion depth,diffusion coefficient,and radon transfer velocity at the gas–liquid interface on radon migration and exhalation of radon-containing *** on the numerical simulation results,an estimation model for the radon retardation rate was *** effectiveness of the CFD simulation was evaluated by comparing the experimental and simulated variation values of the radon retardation rate with the coverage area *** The effect of radon transfer velocity on radon retardation in water bodies was minor and insignificant according to the appropriate value;therefore,an estimation model of the radon retardation rate of the coverage of a radon-containing water body was constructed using the synergistic impacts of three factors:area coverage rate,immersion depth,and diffusion *** deviation between the experimental and simulated results wassimulation conditions,an estimation model of the radon retardation rate of covering floats in water bodies under the synergistic effect of multiple factors was obtained,which provides a reference for designing covering floats for radon retardation in radoncontaining water.

关键词： Radon-containing water Radon retardation rate CFD Coverage experiment Optimized design

A passive sampler for synchronously measuring inorganic and organic pollutants in sediment porewater:Configuration and field application

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Journal of Environmental Sciences 2024年第2期136卷 201-212页

作者： Pei Lei Mingying Chen Nan Rong Wenzhong Tang Hong Zhang School of Environment Nanjing Normal UniversityNanjing 210023China State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China South China Institute of Environmental Sciences Ministry of Ecology and EnvironmentGuangzhou 510530China State Environmental Protection Key Laboratory of Water Environmental simulation and Pollution {1. Guangzhou 510530China University of Chinese Academy of Sciences Beijing 100049China

In situ measurement of multiple pollutants coexisting in sediment porewater is an essential step in comprehensively assessing the bioavailability and risk of pollutants,but to date,this needs to be better *** this study,a passive sampler,consisting of an“I-shaped”supporting frame and inorganic/organic sampling units,incorporating equilibrium dialysis theory and kinetic/equilibrium sorption principle,was developed for the synchronous measurement of inorganic(e.g.,phosphorus and metal(loid)s)and organic pollutants(e.g.,parent and substituted PAHs).The equilibrium time and sampling rates were explored in laboratory tests to support in situ *** of pollutants in porewater within a vertical resolution of centimeters,i.e.,1.cm and 2 cm for inorganic and organic pollutants,respectively,were obtained by field deployment of the sampler for further estimation of diffusive fluxes across the sediment-water *** results suggested that the role of sediments for a specific pollutant may change(e.g.,from“sink”to“source”)during the sampling *** study demonstrated the feasibility of synchronous measurement of inorganic and organic pollutants in sediment porewater by the passive *** addition,it provided new insight for further investigation into the combined pollution effects of various pollutants in sediments.

关键词： Passive sampling Bioavailability Polycyclic aromatic hydrocarbons Combined pollution Diffusive flux

Evolutionary Diversity of Coxsackievirus A6 Causing Severe Hand,Foot,and Mouth Disease—China,201.-2023

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China CDC weekly 2024年第20期6卷 442-449页

作者： Huanhuan Lu Jinbo Xiao Wenhui Wang Dongmei Yan Tianjiao Ji Qian Yang Haiyan Wei Yanhua Du Yunting Zeng Jun Guo Jianhua Chen Hanri Zeng Yingying Liu Shuaifeng Zhou Hong Ji Jianxing Wang Xiaofang Zhou Yong Zhang National Key Laboratory of Intelligent Tracking and Forecasting for Infectious Diseases World Health Organization Polio Reference Laboratory for the Western Pacific RegionKey Laboratory of Laboratory BiosafetyNational Health and Key Laboratory of Laboratory Biosafety of the National Health CommissionNational Institute for Viral Disease Control and PreventionChinese Center for Disease Control and PreventionBeijingChina Linyi center for Disease {1. and Prevention Linyi CityShandong ProvinceChina Henan Provincial center for Disease {1. and Prevention Zhengzhou CityHenan ProvinceChina Shaanxi Provincial center for Disease {1. and Prevention Xi’an CityShaanxi ProvinceChina Hainan Provincial center for Disease {1. and Prevention Haikou CityHainan ProvinceChina Guizhou Provincial center for Disease {1. and Prevention Guiyang CityGuizhou ProvinceChina Gansu Provincial center for Disease {1. and Prevention Lanzhou CityGansu ProvinceChina Guangdong Provincial center for Disease {1. and Prevention Guangzhou CityGuangdong ProvinceChina Hebei Provincial center for Disease {1. and Prevention Shijiazhuang CityHebei ProvinceChina Hunan Provincial center for Disease {1. and Prevention Changsha CityHunan ProvinceChina Jiangsu Provincial center for Disease {1. and Prevention Nanjing CityJiangsu ProvinceChina Shandong Provincial center for Disease {1. and Prevention Jinan CityShandong ProvinceChina Yunnan Provincial center for Disease {1. and Prevention Kunming CityYunnan ProvinceChina

Introduction:Coxsackievirus A6(CVA6)has emerged as a significant pathogen responsible for severe cases of hand,foot,and mouth disease(HFMD).This study aims to delineate the demographic characteristics and analyze the viral evolution of severe HFMD associated with CVA6,thereby assisting in its surveillance and ***:In this investigation,74 strains of CVA6 were isolated from samples collected from severe HFMD cases between 201. and *** VP1.gene sequences of CVA6 were amplified and analyzed to assess population historical dynamics and evolutionary characteristics using BEAST,DnaSP6,and ***:A significant portion(94.4%)of severe CVA6-associated HFMD cases(51.out of 54,with 20 lacking age information)were children under 5 years *** the 74 CVA6 strains analyzed,72 belonged to the D3a sub-genotype,while only two strains were D2 *** average genetic distance between VP1.sequences prior to 201. was 0.027,which increased to 0.051.when compared to sequences *** population dynamics analysis indicated three significant population expansions of severe CVA6-associated HFMD during 201.-201.,201.-201.,and 201.-2020,resulting in the formation of 65 distinct *** with the MCC tree findings,transitioning between regional haplotypes required multiple base substitutions,showcasing an increase in population diversity during the evolutionary process(from 1. haplotypes in 201. to 55 haplotypes over the subsequent decade).Conclusions:CVA6,associated with severe HFMD,is evolving and presents a risk of outbreak ***,enhanced surveillance of severe HFMD is imperative.

关键词： thereby subsequent finding

Cost dynamics of onshore wind energy in the context of China's carbon neutrality target

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Environmental Science and Ecotechnology 2024年第3期19卷 109-117页

作者： Shi Chen Youxuan Xiao Chongyu Zhang Xi Lu Kebin He Jiming Hao School of Environment State Key Joint Laboratory of Environment Simulation and Pollution ControlTsinghua UniversityBeijing100084China Beijing Laboratory of Environmental Frontier Technologies Tsinghua UniversityBeijing100084China Institute for Carbon Neutrality Tsinghua UniversityBeijing100084China

Wind energy has become one of the most important measures for China to achieve its carbon neutrality *** spatial and temporal evolvement of economic competitiveness for wind energy becomes an important concern in shaping the decarbonization pathway in *** has been an urgent need in power system planning to model the future dynamics of cost decline and supply potential for wind power in the context of carbon neutrality until *** studies often fail to capture the rapid decline in the cost of wind power generation in recent years,and the prediction of wind power cost decline is more conservative than the *** study constructs an integrated model to evaluate the cost-competitiveness and grid parity potential of China's onshore wind electricity at fine spatial resolution with updated *** indicate that the total onshore wind potential amounts to 54.0 *** average levelized cost of wind power is expected to decline from CNY 0.39 kWh^(-1.in 2020 to CNY 0.30 and CNY 0.21.kWh^(-1.in 2030 and 2060.28.3%,67.6%,and 97.6%of the technical potentials hold power costs lower than coal power in 2020,2030,and 2060.

关键词： Wind power Carbon neutrality Electricity potential Economic competitiveness Grid parity

Revealing the intrinsic mechanisms for accelerating nitrogen removal efficiency in the Anammox reactor by adding Fe(Ⅱ)at low temperature

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Chinese Chemical Letters 2024年第8期35卷 341-348页

作者： Linjing Li Wenlai Xu Jianyong Ning Yaping Zhong Chuyue Zhang Jiane Zuo Zhicheng Pan State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China State Key Joint Laboratory of Environment simulation and Pollution {1. School of EnvironmentTsinghua UniversityBeijing 100084China National Postdoctoral Research Station Haitian Water GroupChengdu 610213China National Enterprise Technology center Haitian Water GroupChengdu 610213China Water Safety and Water Pollution control Engineering Technology Research {1. in Sichuan Province Chengdu 610213China Laboratory of Municipal Wastewater Treatment Technology in Sichuan Province Chengdu 610213China Institute of Environment and Ecology Tsinghua Shenzhen International Graduate SchoolShenzhen 518055China

Fe(Ⅱ)is an essential trace element for anaerobic ammonium oxidation bacteria(AAOB)metabolism,and can improve the nitrogen removal efficiency of anaerobic ammonia oxidation(Anammox).Here we oper-ated two identical expanded granular sludge bed(EGSB)reactors at low temperature(1.±3℃)for 1.4 *** 1.R_(1.)received additional Fe(Ⅱ)(0.1. mmol/L)during the late startup phase,while reactor 0(R_(0))served as the control and did not receive extra Fe(Ⅱ).Nitrogen removal in R_(1.became stable at 55 d of operation,ten days earlier than R_(0).The nitrogen removal rate(NRR)of R_(1. was 1.64 kg N m^(−3)d^(−1.and its TN removal rate was as high as 89%,while R_(0)only reached 75%.The addition of Fe(Ⅱ)was fur-ther beneficial to aggregation and stability of the granular sludge,and the used sludge of both reactors showed enrichment for AAOB populations compared to the inoculum,for instance,increased abundance of Candidatus-Kuenenia and in particular of Candidatus-Brocadia(from 0.1.%to 1..1.%in R_(0)and 7.79%in R_(1.).Diverse microbial species and complex microbial network structure in R_(1.compared to R_(0)promoted the coupled denitrogenation by Anammox,dissimilatory nitrate reduction to ammonium(DNRA),nitrate-dependent Fe oxidation(NDFO),and ferric ammonium oxidation(Feammox).In addition,the microbial community in R_(1.was more resistant to short-term low temperature(2-7℃)starvation,illustrating a further positive effect of adding Fe(Ⅱ)during the startup phase of an Anammox reactor.

关键词： Ambient low temperature Anammox Fe(Ⅱ) Extracellular polymeric substances Microbial community Microbial network analysis