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Coronavirus disease 2019 outbreak in beijing's Xinfadi Market, China: a modeling study to inform future resurgence response

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Infectious Diseases of Poverty 2021年第3期10卷 122-123页

作者： Xiao-Li Wang Xin Lin Peng Yang Zun-You Wu Gang Li Jennifer M.McGoogan Zeng-Tao Jiao Xin-Jun He Si-Qi Li Hong-Hao Shi Jing-Yuan Wang Sheng-Jie Lai Chun Huang Quan-Yi Wang beijing Research Center for Preventive Medicine Beijing Center for Disease Prevention and ControlBeijingChina School of Computer Science and Engineering Beihang UniversityBeijingChina WorldPop School of Geography and Environmental ScienceUniversity of SouthamptonSouthamptonUK 不详

Background:A local coronavirus disease 2019(COVID-19)case confirmed on June 11,2020 triggered an outbreak in beijing,China after 56 consecutive days without a newly confirmed ***-pharmaceutical interventions(NPIs)were used to contain the source in Xinfadi(XFD)*** rapidly control the outbreak,both traditional and newly introduced NPIs in eluding large-scale management of high-risk populations and expanded severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)PCR-based screening in the general population were conducted in *** aimed to assess the effectiveness of the response to the COVID-19 outbreak in beijing's XFD market and inform future response efforts of resurgence across regions.

关键词： Public health Nonpharmaceutical intervention COVID-19 SARS-CoV-2 beijing

Modeling Patch Characteristics of Farmland Loss for Site Assessment in Urban Fringe of beijing, China

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Chinese Geographical Science 2013年第3期23卷 365-377页

作者： LIU Xiaona ZHANG Weiwei LI Hong SUN Danfeng College of Resources and Environmental Sciences China Agricultural University Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Institute of System Comprehensive Development Beijing Academy of Agriculture and Forest Science

Farmland protection and delimitation in the urban fringe considers not only natural factors but also the spatial characters and site factors. Taking Daxing District, beijing in China as a case study, this paper used landscape ecology and power-law methods to ana- lyze and evaluate farmland loss during the period of 2004~2007 based on the interpretation results of SPOT5 remote sensing images in 2004 and 2007. At the patch level, we selected four landscape indices, namely patch size, shape index, the nearest neighbor distance between farmland and construction land （including residential land and other construction land）, and cropping type, to evaluate the risk of farmland loss and establish a farmland site analysis indicator system. The results showed that patch size and shape index have a sig- nificant positive correlation with farmland loss, whereas the distance to construction land has a clear negative correlation with farmland loss. As regards cropping type, fallow farmland is much easier for non-agriculUlral use than cultivated farmland. The relative transition ratio among vegetable land, fallow farmland and cultivated farmland is 1 ： 5.6 ： 1. The patch size of lost farmland follows a power-law distribution, indicating that not only small parcels but also large parcels can be lost. Patch size less than 4 ha or more than 15 ha is in high loss risk, between 4 ha and 10 ha in medium loss risk, and larger than 10 ha and less than 15 ha in low risk. Farmland with a more regular shape has a higher likelihood of loss. Patch shape index less than 2.0 is in high loss risk, between 2.0 and 3.0 in medium loss risk, and larger than 3.0 in low risk. Construction land has a varying impact on farmland loss, the residential land effeeted distance is 1000 m, and that of the other construction land is 2000 m. This analysis showed the relationships between site factors and farmland loss, and the analysis framework can provide support and reference for farmland protection and delimi

关键词： farmland loss loss risk site analysis logistic regression analysis power-law distribution

Study on the Measurement of Industrial Structure “Sophistication,Rationalization and Ecologicalization” Based on the Dynamic Analysis of Grey Relations——A Case Study of beijing-Tianjin-Hebei

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Journal of Systems Science and Information 2020年第2期11卷 130-147页

作者： Shiyi YUAN Xiaopeng SUN Weiguo CHEN Yongwu LI School of Economics and Management Beijing University of TechnologyBeijing 100124China

The beijing-Tianjin-Hebei region is one of the regions with the most dynamic economies,highest degrees of openness,strongest innovation capacities and largest populations,as well as an important engine driving China’s economic ***,the development of the beijingTianjin-Hebei region faces many difficulties,including an inefficient distribution of regional functions,imbalance in industrial structure,low sophistication,and serious overburdening of resources and the *** the overall coordinated development of the region has become an urgent *** this paper,according to the conventions of industrial structure optimization,the three core indicators of regional industrial structure rationalization,sophistication and ecologicalization are *** the help of the grey dynamic correlation model,the three indicators are coupled with the economic growth rate,and the industrial structure optimization index of the beijing-Tianjin-Hebei region is comprehensively *** study shows that rationalization of the industrial structure in the beijing-Tianjin-Hebei region is increasing but that this trend is not obvious;sophistication of the industrial structure is relatively high and has also been operating at a high level;however,the overall ecological level of the industrial structure in the beijing-Tianjin-Hebei region is not high and presents the characteristics of high in the middle and low at both *** terms of the relationship between industrial structure and economic growth in the beijing-Tianjin-Hebei region,ecologicalization of the industrial structure has the greatest influence on economic growth,followed by sophistication of the industrial structure,and rationalization of the industrial structure has the weakest influence.

关键词： ecologicalization grey dynamic analysis degrees industrial structure sophistication rationalization

Prevalence of Tuberculosis among Close Contacts of Index Cases in 27 Universities in beijing,China,2017-2018

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Biomedical and Environmental Sciences 2020年第10期33卷 780-784页

作者： ZHAO Fei ZHANG Zhi Guo MA Shu Bo YANG Zhen HE Yan Ping WANG Lu Qin OWITI Philip MA Chao LI Tao DU Xin ZHANG Can You CHENG Jun WANG Li Xia HE Guang Xue ZHANG Hui LI Ke Xin Clinical Trial Center Beijing HospitalNational Center of Gerontology/Institute of Geriatric MedicineChinese Academy of Medical SciencesBeijing 100730China National Center for TB Control and Prevention Chinese Center for Disease Control and PreventionBeijing 102206China Department of Epidemiology of Microbial Diseases Yale School of Public HealthYale universityNew HavenCTUSA beijing Changping Institute for Tuberculosis Prevention and Treatment Beijing 102200China The International Union Against Tuberculosis and Lung Disease ParisFrance The National Tuberculosis Leprosy and Lung Disease ProgramNairobiKenya National Immunization Program Chinese Center for Disease Control and PreventionBeijing 102206China Department of Science and Technology Chinese Center for Disease Control and PreventionBeijing 102206China

The World Health Organization(WHO)launched the‘End TB Strategy’,which aims to reduce the mortality and incidence rate of tuberculosis(TB)by 95% and 90% by 2035,respectively,compared with the levels in *** achieve these targets and milestones,the strategy set three pillars and 10 indicators,one of which is systematic screening of contacts and high-risk groups[1].

关键词： mortality tuberculosis Cases

Comparison of thermal and light performance in two typical Chinese solar greenhouses in beijing

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International Journal of Agricultural and Biological Engineering 2019年第1期12卷 24-32页

作者： Fan Xu Chao Shang Hongling Li Xuzhang Xue Weituo Sun Hong Chen Yinkun Li Zhenhe Zhang Xinxu Li Wenzhong Guo beijing Research Center of Intelligent Equipment for Agriculture Beijing Academy of Agriculture and Forestry SciencesBeijing 100097China Plant Science and Technology College Beijing University of AgricultureBeijing 102206China beijing Extension Station for Agricultural Technology Beijing 100101China National Agricultural Technology Extension and Service Center Ministry of Agriculture and Rural Affairs of the People’s Republic of ChinaBeijing 100125China

Solar greenhouses have been used for producing vegetables in northern China during early spring,late autumn or *** improve the thermal performance of solar greenhouses,a traditional type and a retrofitted design were comparatively *** the retrofitted design,three adjustments were incorporated:the material and structure of the walls,south-facing roof angle,and structure of the north-facing *** results indicated that the thermal and light performance of the retrofitted greenhouse was much better than that of the traditional ***,the daily mean temperature,minimum air temperature,and soil temperature inside the greenhouses after retrofit ting were increased by 1.3,2.4,and 1.9℃,respectively,meanwhile,the daily total solar radiation and PAR were increased by 28.2%and 9.2%,*** wall temperature and its daily variation range were reduced with increasing depth and *** characteristic analysis of heat storage and release indicated that higher locations have longer heat storage,and shorter heat release time in vertical direction,as well as a lower ratio of heat release to *** horizontal direction,the western wall has the shortest heat storage time but the highest heat release flux ***,the heat storage time of the wall is 1.5 h less than that of the *** heat storage flux density of the wall is 1.5 times of that of the soil,but the heat release flux is only 61%of the soil’s *** total wall heat storage is half of that of the soil in the greenhouse;the total wall heat release amount is only a quarter of that of the ***,the thermal environment of solar greenhouses can be further improved by improving the thermal insulation properties of the wall.

关键词： structural change heat storage performance heat flux back wall thermal environment

Distributed Estimation and Analysis of Precipitation Recharge Coefficient in Strongly-exploited beijing Plain Area, China

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Chinese Geographical Science 2017年第1期27卷 88-96页

作者： PAN Yun GONG Huili SUN Ying WANG Xinjuan DING Fei College of Resources Environment and Tourism Capital Normal University Beijing 100048 China beijing Institute of Hydrogeology and Engineering Geology Beijing 100195 China College of Architecture and Civil Engineering Beijing University of Technology Beijing 100124 China

The precipitation recharge coefficient(PRC), representing the amount of groundwater recharge from precipitation, is an important parameter for groundwater resources evaluation and numerical simulation. It was usually obtained from empirical knowledge and site experiments in the 1980 s. However, the environmental settings have been greatly modified from that time due to land use change and groundwater over-pumping, especially in the beijing plain area(BPA). This paper aims to estimate and analyze PRC of BPA with the distributed hydrological model and GIS for the year 2011 with similar annual precipitation as long-term mean. It is found that the recharge from vertical(precipitation + irrigation) and precipitation is 291.0 mm/yr and 233.7 mm/yr, respectively, which accounts for 38.6% and 36.6% of corresponding input water. The regional mean PRC is 0.366, which is a little different from the traditional map. However, it has a spatial variation ranging from –7.0% to 17.5% for various sub-regions. Since the vadose zone is now much thicker than the evaporation extinction depth, the land cover is regarded as the major dynamic factor that causes the variation of PRC in this area due to the difference of evapotranspiration rates. It is suggested that the negative impact of reforestation on groundwater quantity within BPA should be well investigated, because the PRC beneath forestland is the smallest among all land cover types.

关键词： groundwater recharge distributed hydrological model land cover geographic information systems

Analysis and Monitoring of Indoor Radon Concentrations of 37 Kindergartens — beijing Municipality, China, 2023

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China CDC weekly 2024年第13期6卷 272-276页

作者： Meinan Yao Kuke Ding Xiaozhe Tang Yunyun Wu Yanchao Song Shuyuan Liu Bin Bai Li Zhang Yongzhong Ma Institute for Radiation Hygiene Protection Beijing Center for Disease Prevention and ControlBeijingChina Chinese Center for Disease Control and Prevention BeijingChina Key Laboratory of Radiological Protection and Nuclear Emergency&National Institute for Radiological Protection Chinese Center for Disease Control and PreventionBeijingChina

Introduction:Radon(222Rn or 222radon)is a radioactive gas emitted from building materials,foundations,and *** are especially susceptible to radon exposure,underscoring the need to assess indoor radon levels in *** study monitored radon concentrations in 37 beijing kindergartens from June to October ***:A random sample of 37 kindergartens was selected from 18 administrative districts in *** indoor radon concentration was measured using the solid track accumulation method,with radon detectors continuously monitored over a 3-month ***:The mean indoor radon level in 37 kindergartens,observed at 252 monitoring points,was 84.3 Bq/m^(3),with values varying from 12.9 to 263.5 Bq/m^(3).About 20.2%of points showed radon levels between 100.0 and 200.0 Bq/m^(3),while 2.4%exceeded 200.0 Bq/m^(3).Notably,radon levels were significantly elevated on the ground floor compared to the upper ***:Indoor radon levels in 37 kindergartens remained below the national standard limit of 300.0 Bq/m^(3) for buildings(GB/T 16146-2015).Nonetheless,18.9%of the kindergartens exceeded the 100.0 Bq/m^(3) limit set for new *** is advised to improve radon monitoring in kindergartens and consider developing a national standard for maximum permissible radon levels in such facilities.

关键词： Radon limit floor

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 *** 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 ***:We included patients initially admitted to the hospital for SARS-CoV-2 infection between November 5 and December 25,*** collected daily oropharyngeal swabs for quantitative reverse transcriptase-polymerase chain reaction tests using commercial *** depicted the cycle threshold(Ct)values for amplification of ORF1ab and N genes from individual patients in age-specific groups in a time ***: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,*** 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 *** Ct values for N gene amplification took longer to rise above 35 than those for ORF1ab gene ***: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 *** a result,the time to resolution of Omicron infection increased with increasing age.

关键词： patients admitted younger

A climatic environmental performance assessment method for ecological city construction:Application to beijing Yanqi Lake

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Advances in Climate Change Research 2015年第1期6卷 23-35页

作者： FANG Xiao-Yi CHENG Chen LIU Yong-Hong DU Wu-Peng XIAO Xiao-Jun DANG Bing beijing Municipal Climate Center beijing Institute of Architectural Design

In contrast to the input perspective for evaluating planning metrics, this research takes the climatic environmental output effects as the starting point for assessing ecological city construction. Based on approaches such as observation data analysis, meteorological model simulation, and remote sensing, a set of climatic environmental performance assessment methods is developed and established. These methods mainly focus on surface ventilation assessment and urban thermal environment assessment. With the Yanqi Lake ecological development demonstration area located in Huairou district, beijing as an example, the assessment of the local climatic environment before and after the construction are conducted, and relevant policy suggestions for urban planning and construction are presented. The results show that after development, the ventilation capacity will decrease overall and the ventilation potential index will decrease from 0.53 to 0.44. While this is not a large reduction, and is still at a favorable level, the ventilation potential in some local areas will markedly decrease. Furthermore, the thermal environment will become poorer to some extent; the urban heat island(UHI) area and intensity will increase compared with the current situation;continuous heat islands may occur in local areas; the UHI potential index of the core area will rise from 0.0878 to 0.1217(still a favorable level).Therefore, urban surfaces should be carefully developed and arranged during planning. It is suggested that the negative impacts of large areas of urban construction on the local climatic environment in the Yanqi Lake could be mitigated by 1) strengthening the airflow by introducing fresh,cold, northwesterly air via constructed ventilation corridors, 2) increasing the number of ecological cold sources, particularly for water bodies and green belts to prevent the UHI in the southern region of Yanqi Lake from becoming linked with each other, and 3) considering a pre-program before sub

关键词： Ecological city construction Ventilation environment Thermal environment Performance assessment Yanqi Lake ecological development demonstration area