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Conjunctival microbiota variations in a subset of middleaged and elderly individuals from Beijing,China
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作者 Tian-Yao Zhao Yu-Chen Wang +4 位作者 Ying-Juan Sun Jun-Yue Wang Xiao-Dan Jiang Xue-Min Li Ai-Hua Deng 《International Journal of Ophthalmology(English edition)》 2025年第2期237-243,共7页
AIM:To isolate and identify the conjunctival microbiota of cataract patients and analyze the associated influencing factors.METHODS:This study recruited 216 participants(216 eyes)from April 2022 to July 2022.Under the... AIM:To isolate and identify the conjunctival microbiota of cataract patients and analyze the associated influencing factors.METHODS:This study recruited 216 participants(216 eyes)from April 2022 to July 2022.Under the condition of no antibiotic use prior to cataract surgery,sterile swabs were used to collect samples from the lower conjunctival sac.Bacterial cultures were then conducted,followed by species identification through 16S rDNA gene sequencing.Clinical factors associated with positive or negative bacterial isolation rates were analyzed,including age,gender,meibomian gland dysfunction(MGD),history of hypertension,history of diabetes,history of cancer,history of infectious diseases and the habit of wearing masks.RESULTS:Among the 216 eyes,78 eyes yielded isolates,with an isolation rate of 36.11%,detecting a total of 122 strains.Gram-positive rods accounted for 49.18%(60 strains),gram-positive cocci accounted for 45.08%(55 strains),gram-negative bacteria accounted for 4.92%(6 strains),and fungi accounted for 0.82%(1 strain).This study found that the most abundant genera in the conjunctival sac were Corynebacterium(42.62%),Staphylococcus(31.15%),Micrococcus(9.84%),Acinetobacter(4.10%),and Bacillus(3.28%).Furthermore,age(P=0.006),gender(P=0.039),diabetes(P=0.003),history of infectious diseases(P=0.02),and duration of mask replacement(P<0.001)were important factors influencing the positive bacterial culture of the conjunctival microbiota.Although hypertensive patients exhibited a higher isolation rate of conjunctival bacteria,it did not reach statistical significance,and the history of cancer did not affect the isolation rate of the conjunctival microbial community in cataract patients before surgery.CONCLUSION:Potential changes are observed in the conjunctival microbiota among a sample of middleaged and elderly individuals from Beijing,China.Notably,an increased isolation rate of Corynebacterium and Micrococcus is detected,suggesting a possible change in the microbial balance that requires further investigation and attention from the ophthalmological community.Advanced age,female gender,MGD,diabetes,a recent history of infectious diseases,and inadequate mask-wearing habits are potentially significant factors associated with the conjunctival microbiota.These factors should be considered in the development of strategies to prevent perioperative infections in cataract surgery patients. 展开更多
关键词 conjunctival microbiota 16S rDNA middle-aged and elderly population mask cataract surgery
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Trends of surface ozone based on hourly concentrations in the Beijing–Tianjin–Hebei region during 2017–2021 被引量:1
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作者 Xiaoyan Wang Huihui Zheng +3 位作者 Bing Liu Shuyan Xie Yonghai Huang Shuai Wang 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第6期26-32,共7页
As a typical secondary air pollutant,surface ozone has been monitored routinely since 2013 in China.Most studies on the spatiotemporal variation of ozone have been centered around the daily maximum 8-h average,with li... As a typical secondary air pollutant,surface ozone has been monitored routinely since 2013 in China.Most studies on the spatiotemporal variation of ozone have been centered around the daily maximum 8-h average,with little attention paid to the trends of hourly ozone,especially hourly ozone exceedances.Focusing on hourly ozone exceedances and peak values,the spatiotemporal trends of hourly ozone at 77 sites in 13 cities of the Beijing-Tianjin-Hebei(BTH)region during 2017-2021 were analyzed in this study.The number of hours with exceedances(N_(H200))in 2019 was nearly three times that of 2021.On a five-year average,the percentage of cumulative NH200 in June accounted for up to 40.5%of all hourly exceedances.Cities in central Hebei Province had the highest cumulative annual N_(H200).June had the highest average hourly ozone exceeded multiples of 0.158.The top two cities with the highest average exceeded multiple were Tangshan(0.166)and Beijing(0.158).Tangshan and Xingtai ranked as the top two in terms of the mean of the 10 highest daily maximum ozone concentrations(MTDM),with 286.74 and 285.37μg m^(−3),respectively.The gap between the MTDM and the daily maximum of hourly ozone averaged over all sites had narrowed to 97.88μg m^(−3) in 2021,much lower than that in other years,which indicated that the stability and convergence of ozone pollution in BTH region had been enhanced in 2021 to some extent. 展开更多
关键词 Surface ozone Hourly concentration Ozone exceedance Peak value Beijing-tianjin-hebei region
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Scientific Advances and Weather Services of the China Meteorological Administration’s National Forecasting Systems during the Beijing 2022 Winter Olympics
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作者 Guo DENG Xueshun SHEN +23 位作者 Jun DU Jiandong GONG Hua TONG Liantang DENG Zhifang XU Jing CHEN Jian SUN Yong WANG Jiangkai HU Jianjie WANG Mingxuan CHEN Huiling YUAN Yutao ZHANG Hongqi LI Yuanzhe WANG Li GAO Li SHENG Da LI Li LI Hao WANG Ying ZHAO Yinglin LI Zhili LIU Wenhua GUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期767-776,共10页
Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational... Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational techniques,and experience.This made providing meteorological services for this event particularly challenging.The China Meteorological Administration(CMA)Earth System Modeling and Prediction Centre,achieved breakthroughs in research on short-and medium-term deterministic and ensemble numerical predictions.Several key technologies crucial for precise winter weather services during the Winter Olympics were developed.A comprehensive framework,known as the Operational System for High-Precision Weather Forecasting for the Winter Olympics,was established.Some of these advancements represent the highest level of capabilities currently available in China.The meteorological service provided to the Beijing 2022 Games also exceeded previous Winter Olympic Games in both variety and quality.This included achievements such as the“100-meter level,minute level”downscaled spatiotemporal resolution and forecasts spanning 1 to 15 days.Around 30 new technologies and over 60 kinds of products that align with the requirements of the Winter Olympics Organizing Committee were developed,and many of these techniques have since been integrated into the CMA’s operational national forecasting systems.These accomplishments were facilitated by a dedicated weather forecasting and research initiative,in conjunction with the preexisting real-time operational forecasting systems of the CMA.This program represents one of the five subprograms of the WMO’s high-impact weather forecasting demonstration project(SMART2022),and continues to play an important role in their Regional Association(RA)II Research Development Project(Hangzhou RDP).Therefore,the research accomplishments and meteorological service experiences from this program will be carried forward into forthcoming highimpact weather forecasting activities.This article provides an overview and assessment of this program and the operational national forecasting systems. 展开更多
关键词 Beijing Winter Olympic Games CMA national forecasting system data assimilation ensemble forecast bias correction and downscaling machine learning-based fusion methods
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Spatial and temporal variation of water clarity in typical reservoirs in the Beijing-Tianjin-Hebei region observed by GF 1-WFV satellite data
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作者 Chang CAO Junsheng LI +2 位作者 Xiaodong JIA Shenglei WANG Bo WAN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第4期1048-1060,共13页
Rapidly monitoring regional water quality and the changing trend is of great practical and scientific significance,especially for the Beijing-Tianjin-Hebei(BTH)region of China where water resources are relatively scar... Rapidly monitoring regional water quality and the changing trend is of great practical and scientific significance,especially for the Beijing-Tianjin-Hebei(BTH)region of China where water resources are relatively scarce and inland water bodies are generally small.The remote sensing data of the GF 1 satellite launched in 2013 have characteristics of high spatial and temporal resolution,which can be used for the dynamic monitoring of the water environment in small lakes and reservoirs.However,the water quality remote sensing monitoring model based on the GF 1 satellite data for lakes and reservoirs in BTH is still lacking because of the considerable differences in the optical characteristics of the lakes and reservoirs.In this paper,the typical reservoirs in BTH-Guanting Reservoir,Yuqiao Reservoir,Panjiakou Reservoir,and Daheiting Reservoir are taken as the study areas.In the atmospheric correction of GF 1-WFV,the relative radiation normalized atmospheric correction was adopted after comparing it with other methods,such as 6 S and FLAASH.In the water clarity retrieval,a water color hue angle based model was proposed and outperformed other available published models,with the R 2 of 0.74 and MRE of 31.7%.The clarity products of the four typical reservoirs in the BTH region in 2013-2019 were produced using the GF 1-WFV data.Based on the products,temporal and spatial changes in clarity were analyzed,and the main influencing factors for each water body were discussed.It was found that the clarity of Guanting,Daheiting,and Panjiakou reservoirs showed an upward trend during this period,while that of Yuqiao Reservoir showed a downward trend.In the influencing factors,the water level of the water bodies can be an important factor related to the water clarity changes in this region. 展开更多
关键词 GF 1 satellite atmospheric correction CLARITY BEIJING-TIANJIN-HEBEI spatial and temporal change analysis
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Formation mechanisms and resource potential of carbonate geothermal reservoirs in the Beijing-Tianjin-Hebei plain
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作者 Xinwei Wang Tinghao Wang +3 位作者 Nanan Gao Xiang Mao Lu Luo Xingchen Lu Haiquan Li 《Energy Geoscience》 EI 2024年第3期175-188,共14页
Investigating the formation mechanisms of carbonate geothermal reservoirs is of theoretical and practical significance for summarizing the formation pattern of geothermal resources and further guiding their effective ... Investigating the formation mechanisms of carbonate geothermal reservoirs is of theoretical and practical significance for summarizing the formation pattern of geothermal resources and further guiding their effective exploitation.The Beijing-Tianjin-Hebei Plain(BTHP),predominantly located within the Jizhong Depression and Cangxian Uplift in the Bohai Bay Basin,serves as the primary region for geothermal exploitation and utilization in China.More than 1500 geothermal wells have been drilled therein,with water temperature at the wellhead ranging from 55 to 110°C,single-well flow rate ranging between 80 and 120 m^(3)/h,and cumulative heating area exceeding 100×10^(6)m^(3).However,the exploration and research in the region remain limited overall.As per the previous geothermal and petroleum exploration results and the latest geothermal drilling data,this study comprehensively evaluated the geothermal resources of karst geothermal reservoirs.The results show that two suites of carbonate karst reservoirs,namely the Jxw Formation and the Ordovician strata,have primarily developed in the BTHP,and their formation and evolution can be divided into four stages:the Mesoproterozoic-Early Paleozoic stage with carbonate sedimentation and the development of interlayer karst,the Late Paleozoic stage with the development of direct sedimentary cover,the Mesozoic stage with compressional uplifting and development of buried hill karst,and the Cenozoic stage with regional cover deposition and the modification and finalization of karst geothermal reservoirs.Accordingly,the porosity evolution history of the geothermal reservoirs is composed of three stages,namely a significant decrease followed by a minor increase,a gradual decline,and then a small fluctuation from increase to decrease before slowly rising again.The karstification in geothermal reservoirs can be summarized into quasi-syngenetic karstification,epigenetic karstification,and burial karstification,which can be subdivided into seven subcategories.The carbonate geothermal reservoirs in the study area boast total geothermal resources of 53.821×10^(9)GJ,or 184.155×10^(9)t of standard coal equivalent(tce),and the annual exploitable geothermal resources in the urban area can heat an area of(400‒500)×10^(6)m^(3),indicating great potential of geothermal exploitation. 展开更多
关键词 Carbonate geothermal reservoir Formation mechanism Karstification type Resource assessment Beijing-Tianjin-Hebei plain(BTHP)
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Spatial-temporal Patterns of Urban Parks’Effects on the Sentiments and Their Associated Factors Based on Social Media Data——a Case Study in Beijing
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作者 YUAN Yuting WANG Juan +3 位作者 WEI Yali ZHU Yanrong SHI Changsheng MENG Bin 《Journal of Geodesy and Geoinformation Science》 CSCD 2024年第2期95-110,共16页
As the pivotal green space,urban parks play an important role in urban residents’daily activities.Thy can not only bring people physical health,but also can be more likely to elicit positive sentiment to those who vi... As the pivotal green space,urban parks play an important role in urban residents’daily activities.Thy can not only bring people physical health,but also can be more likely to elicit positive sentiment to those who visit them.Recently,social media big data has provided new data sources for sentiment analysis.However,there was limited researches that explored the connection between urban parks and individual’s sentiments.Therefore,this study firstly employed a pre-trained language model(BERT,Bidirectional Encoder Representations from Transformers)to calculate sentiment scores based on social media data.Secondly,this study analysed the relationship between urban parks and individual’s sentiment from both spatial and temporal perspectives.Finally,by utilizing structural equation model(SEM),we identified 13 factors and analyzed its degree of the influence.The research findings are listed as below:①It confirmed that individuals generally experienced positive sentiment with high sentiment scores in the majority of urban parks;②The urban park type showed an influence on sentiment scores.In this study,higher sentiment scores observed in Eco-parks,comprehensive parks,and historical parks;③The urban parks level showed low impact on sentiment scores.With distinctions observed mainly at level-3 and level-4;④Compared to internal factors in parks,the external infrastructure surround them exerted more significant impact on sentiment scores.For instance,number of bus and subway stations around urban parks led to higher sentiment scores,while scenic spots and restaurants had inverse result.This study provided a novel method to quantify the services of various urban parks,which can be served as inspiration for similar studies in other cities and countries,enhancing their park planning and management strategies. 展开更多
关键词 urban parks sentiment analysis social media data SEM BEIJING
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Perspectives and Challenges of Family Members in Providing Mental Support to Cancer Patients:A Qualitative Study in Beijing,China
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作者 Wei Wang Lan Li 《Psycho-Oncologie》 SCIE 2024年第4期257-269,共13页
This study explores the perspectives and challenges faced by family members providing mental support to cancer patients in Beijing,China.The primary objective is to understand the emotional and practical roles family ... This study explores the perspectives and challenges faced by family members providing mental support to cancer patients in Beijing,China.The primary objective is to understand the emotional and practical roles family members undertake and the difficulties they encounter.Utilizing a qualitative research design,data were collected through semi-structured interviews with family caregivers of cancer patients.Thematic analysis revealed several key themes:the dual burden of emotional support and caregiving responsibilities,the impact on daily life and personal well-being,the role and effectiveness of external support systems,perceptions of medical staff support,and the common challenges and conflicts faced in caregiving.The findings highlight the critical need for comprehensive support systems that address both the emotional and practical needs of family caregivers.Recommendations for enhancing family-centered support programs in oncology settings are discussed. 展开更多
关键词 Family caregivers mental health support cancer patients qualitative study BEIJING caregiving challenges emotional support healthcare systems
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Analysis of Influencing Factors on Fruit Consumption of Urban and Rural Residents in Beijing
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作者 Zihao WANG Rao CHEN Weimin YANG 《Asian Agricultural Research》 2024年第6期1-4,10,共5页
In light of the rapid expansion of China s economy,there has been a notable shift in the consumption patterns of urban and rural residents.This is evident in the increased consumption of agricultural products,with fru... In light of the rapid expansion of China s economy,there has been a notable shift in the consumption patterns of urban and rural residents.This is evident in the increased consumption of agricultural products,with fruit consumption representing a particularly pronounced trend.The 2023 Beijing Consumption Statistics indicate that demand for fruit is increasing,accompanied by heightened competition for quality and brands.The paper is based on research that examines the current situation of fruit consumption among urban and rural residents in Beijing.The results indicate that when urban and rural residents in Beijing purchase fruits,price is the most significant factor influencing fruit consumption.Taste,appearance,and variety are also considered to be important influencing factors,while the influence of factors such as fruit type,consumption pattern,and fruit brand is relatively minor. 展开更多
关键词 URBAN and RURAL RESIDENTS of BEIJING FRUIT CONSUMPTION Influencing factor CONSUMPTION behavior
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Evaluation of the Spatial Quality of the Greenway on the Tonghui River in Beijing
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作者 ZHENG Keying SUN Shuai 《Journal of Landscape Research》 2024年第1期27-30,共4页
This study organized the current status of tangible cultural heritage along the Tonghui River.The spaces along the Tonghui River were classified according to the farmland,suburban areas,urban residential areas,and urb... This study organized the current status of tangible cultural heritage along the Tonghui River.The spaces along the Tonghui River were classified according to the farmland,suburban areas,urban residential areas,and urban center areas.Spatial analysis of the current situation was conducted through Baidu Street View images,with a focus on evaluating the spatial environment around the tangible cultural heritage.Negative factors affecting the reuse of cultural heritage were analyzed,such as poor appearance of buildings and low accessibility of transportation along the Tonghui River. 展开更多
关键词 Urban water system Beijing-Hangzhou Grand Canal Cultural heritage protection
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Earthquake relocation using a 3D velocity model and implications on seismogenic faults in the Beijing-Tianjin-Hebei region
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作者 Jinxin Hou Yunpeng Zhang +1 位作者 Liwei Wang Zhirong Zhao 《Earthquake Research Advances》 CSCD 2024年第2期55-64,共10页
To enhance the understanding of the geometry and characteristics of seismogenic faults in the Beijing-Tianjin-Hebei region,we relocated 14805 out of 16063 earthquakes(113°E-120°E,36°N-43°N)that occ... To enhance the understanding of the geometry and characteristics of seismogenic faults in the Beijing-Tianjin-Hebei region,we relocated 14805 out of 16063 earthquakes(113°E-120°E,36°N-43°N)that occurred between January 2008 and December 2020 using the double-difference tomography method.Based on the spatial variation in seismicity after relocation,the Beijing-Tianjin-Hebei region can be divided into three seismic zones:Xingtai-Wen'an,Zhangbei-Ninghexi,and Tangshan.(1)The Xingtai-Wen'an Seismic Zone has a northeastsouthwest strike.The depth profile of earthquakes perpendicular to the strike reveals three northeast-striking,southeast-dipping,high-angle deep faults(>10 km depth),including one below the shallow(<10 km depth)listric,northwest-dipping Xinghe fault in the Xingtai region.Two additional deep faults in the Wen'an region are suggested to be associated with the 2006 M 5.1 Wen'an Earthquake and the 1967 M 6.3 Dacheng earthquake;(2)The Zhangbei-Ninghexi Seismic Zone is oriented north-northwest.Multiple northeast-striking faults(10-20 km depth),inferred from the earthquake-intensive zones,exist beneath the shallow(<10 km depth)Xiandian Fault,Xiaotangshan Fault,Huailai-Zhuolu Basin North Fault,Yangyuan Basin Fault and Yanggao Basin North Fault;(3)In the Tangshan Seismic Zone,earthquakes are mainly concentrated near the northeast-striking Tangshan-Guye Fault,Lulong Fault,and northwest-striking Luanxian-Laoting Fault.An inferred north-south-oriented blind fault is present to the north of the Tangshan-Guye Fault.The 1976 M 7.8 Tangshan earthquake occurred at the junction of a shallow northwest-dipping fault and a deep southeast-dipping fault.This study emphasizes that earthquakes in the region are primarily associated with deep blind faults.Some deep blind faults have different geometries compared to shallow faults,suggesting a complex fault system in the region.Overall,this research provides valuable insights into the seismogenic faults in the Beijing–Tianjin–Hebei region.Further studies and monitoring of these faults are essential for earthquake mitigation efforts in this region. 展开更多
关键词 BEIJING-TIANJIN-HEBEI Double difference tomography Earthquake location Seismogenic faults
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Identifying the Hydrochemical Characteristics,Genetic Mechanisms and Potential Human Health Risks of Fluoride and Nitrate Enriched Groundwater in the Tongzhou District,Beijing,North China 被引量:1
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作者 ZHANG Shouchuan LIU Kai +2 位作者 MA Yan WANG Luyao SUN Junliang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期468-476,共9页
Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas an... Fluoride and nitrate enriched groundwater are potential threats to the safety of the groundwater supply that may cause significant effects on human health and public safety,especially in aggregated population areas and economic hubs.This study focuses on the high F^(−)and NO_(3)^(−)concentration groundwater in Tongzhou District,Beijing,North China.A total of 36 groundwater samples were collected to analyze the hydrochemical characteristics,elucidate genetic mechanisms and evaluate the potential human health risks.The results of the analysis indicate:Firstly,most of the groundwater samples are characterized by Mg-HCO_(3) and Na-HCO_(3) with the pH ranging from 7.19 to 8.28 and TDS with a large variation across the range 471-2337 mg/L.The NO_(3)^(−)concentration in 38.89%groundwater samples and the F^(−)concentration in 66.67%groundwater samples exceed the permissible limited value.Secondly,F^(−)in groundwater originates predominantly from water-rock interactions and the fluorite dissolution,which is also regulated by cation exchange,competitive adsorption of HCO_(3)−and an alkaline environment.Thirdly,the effect of sewage disposal and agricultural activities have a significant effect on high NO3-concentration,while the high F^(−)concentration is less influenced by anthropogenic activity.The alkaline environment favors nitrification,thus being conducive to the production of NO_(3)^(−).Finally,the health risk assessment is evaluated for different population groups.The results indicate that high NO_(3)^(−)and F^(−)concentration in groundwater would have the largest threat to children’s health.The findings of this study could contribute to the provision of a scientific basis for groundwater supply policy formulation relating to public health in Tongzhou District. 展开更多
关键词 fluoride concentration nitrate pollution genetic mechanism health risk assessment Tongzhou District
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Comparison between ozonesonde measurements and satellite retrievals over Beijing,China 被引量:2
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作者 Jinqiang Zhang Yuejian Xuan +5 位作者 Jianchun Bian Holger Vomel Yunshu Zeng Zhixuan Bai Dan Li Hongbin Chen 《Atmospheric and Oceanic Science Letters》 CSCD 2024年第1期14-20,共7页
从2013年开始,作者团队使用自主研发电化学原理臭氧探空仪在华北平原北京地区进行每周一次观测.本研究首次使用2013-2019年期间北京地区臭氧探空数据评估Aqua卫星搭载大气红外探测仪(AIRS)和Aura卫星搭载微波临边探测器(MLS)反演垂直臭... 从2013年开始,作者团队使用自主研发电化学原理臭氧探空仪在华北平原北京地区进行每周一次观测.本研究首次使用2013-2019年期间北京地区臭氧探空数据评估Aqua卫星搭载大气红外探测仪(AIRS)和Aura卫星搭载微波临边探测器(MLS)反演垂直臭氧廓线,并对比臭氧探空,AIRS和Aura卫星搭载臭氧监测仪(OMI)臭氧柱总量结果.尽管臭氧探空与卫星反演垂直臭氧廓线在局部高度处差异较大,但整体来说两者较为接近(相对偏差大多<10%).臭氧探空,AIRS和OMI三种仪器测量臭氧柱总量的年变化特征较为一致,其年均臭氧柱总量分别为351.8±18.4 DU,348.8±19.5 DU和336.9±14.2 DU.后续对国内多站点观测数据分析将有助于进一步理解臭氧探空与卫星反演臭氧资料在不同区域的一致性. 展开更多
关键词 臭氧探空 卫星反演 垂直臭氧廓线 臭氧柱总量 华北平原
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A Deep Learning Approach for Forecasting Thunderstorm Gusts in the Beijing–Tianjin–Hebei Region 被引量:1
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作者 Yunqing LIU Lu YANG +3 位作者 Mingxuan CHEN Linye SONG Lei HAN Jingfeng XU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1342-1363,共22页
Thunderstorm gusts are a common form of severe convective weather in the warm season in North China,and it is of great importance to correctly forecast them.At present,the forecasting of thunderstorm gusts is mainly b... Thunderstorm gusts are a common form of severe convective weather in the warm season in North China,and it is of great importance to correctly forecast them.At present,the forecasting of thunderstorm gusts is mainly based on traditional subjective methods,which fails to achieve high-resolution and high-frequency gridded forecasts based on multiple observation sources.In this paper,we propose a deep learning method called Thunderstorm Gusts TransU-net(TGTransUnet)to forecast thunderstorm gusts in North China based on multi-source gridded product data from the Institute of Urban Meteorology(IUM)with a lead time of 1 to 6 h.To determine the specific range of thunderstorm gusts,we combine three meteorological variables:radar reflectivity factor,lightning location,and 1-h maximum instantaneous wind speed from automatic weather stations(AWSs),and obtain a reasonable ground truth of thunderstorm gusts.Then,we transform the forecasting problem into an image-to-image problem in deep learning under the TG-TransUnet architecture,which is based on convolutional neural networks and a transformer.The analysis and forecast data of the enriched multi-source gridded comprehensive forecasting system for the period 2021–23 are then used as training,validation,and testing datasets.Finally,the performance of TG-TransUnet is compared with other methods.The results show that TG-TransUnet has the best prediction results at 1–6 h.The IUM is currently using this model to support the forecasting of thunderstorm gusts in North China. 展开更多
关键词 thunderstorm gusts deep learning weather forecasting convolutional neural network TRANSFORMER
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Efficacy and Safety of Combined Bedaquiline and Delamanid Use among Patients with Multidrug-Resistant Tuberculosis in Beijing,China
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作者 Can Guo Lihui Nie +6 位作者 Yanhua Song Rongmei Liu Xiaoguang Wu Yuanyuan Shang Xuxia Zhang Yu Pang Mengqiu Gao 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第10期1195-1203,共9页
Objectives The combined use of bedaquiline and delamanid(BDQ-DLM)is limited by an increased risk of prolonging the QTc interval.We retrospectively evaluated patients who received DLM/BDQcontaining regimens at a TB-spe... Objectives The combined use of bedaquiline and delamanid(BDQ-DLM)is limited by an increased risk of prolonging the QTc interval.We retrospectively evaluated patients who received DLM/BDQcontaining regimens at a TB-specialized hospital.We aimed to present clinical efficacy and safety data for Chinese patients.Methods This case-control study included patients with multidrug-resistant tuberculosis(MDR-TB)treated with BDQ alone or BDQ plus DLM.Results A total of 96 patients were included in this analysis:64 in the BDQ group and 32 in the BDQ+DLM group.Among the 96 patients with positive sputum culture at the initiation of BDQ alone or BDQ combined with DLM,46 patients(71.9%)in the BDQ group and 29(90.6%)in the BDQ-DLM group achieved sputum culture conversion during treatment.The rate of sputum culture conversion did not differ between the two groups.The time to sputum culture conversion was significantly shorter in the BDQ-DLM group than in the BDQ group.The most frequent adverse event was QTc interval prolongation;however,the frequency of adverse events did not differ between the groups.Conclusion In conclusion,our results demonstrate that the combined use of BDQ and DLM is efficacious and tolerable in Chinese patients infected with MDR-TB.Patients in the BDQ-DLM group achieved sputum culture conversion sooner than those in the BDQ group. 展开更多
关键词 Multidrug resistant TUBERCULOSIS Bedaquiline Delamanid EFFICACY Safety
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High Diversity in Genotypes of Human Rhinovirus Contributes to High Prevalence in Beijing,2018-2022:A Retrospective Multiple-Center Epidemiological Study
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作者 Qing Wang Qi Huang +5 位作者 Qin Luo Xiaofeng Wei Xue Wang Maozhong Li Cheng Gong Fang Huang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第11期1262-1272,共11页
Objective To comprehensively examine the molecular epidemiological characteristics of human rhinovirus(HRV)in Beijing.Methods A total of 7,151 children and adults with acute respiratory tract infections(ARTIs)were rec... Objective To comprehensively examine the molecular epidemiological characteristics of human rhinovirus(HRV)in Beijing.Methods A total of 7,151 children and adults with acute respiratory tract infections(ARTIs)were recruited from 35 sentinel hospitals in Beijing between 2018 and 2022.Their respiratory samples were obtained,and epidemiological and clinical data were collected.Nucleic acid testing for 11 respiratory pathogens,including HRV,was performed on the specimens.We sequenced VP4/VP2 or 5’UTR of HRV isolates to identify their genotypes using phylogenetic analyses.Results HRV was detected in 462(6.5%)cases.A total of 105 HRV genotypes were successfully identified in 359(77.7%)specimens,comprising 247(68.8%)with HRV-A,42(11.7%)with HRV-B,and 70(19.5%)with HRV-C.No predominant genotype was observed.HRV was prevalent year-round with two weak peaks in spring and autumn.HRV detection declined gradually between 2018 and 2022,with seven genotypes disappearing and five genotypes emerging.HRV detection rate decreased by age without resurge among old people.HRV-C was more common among children aged less than 5 years with severe community-acquired pneumonia compared to HRV-A and HRV-B.Adults infected with HRV-B had higher rates of hospitalization,intensive care unit admission,and complications than those infected with HRV-A and HRV-C.Conclusion HRV epidemics in Beijing were highly dispersed in genotypes,which probably resulted in a high prevalence of HRV infection,attenuated its seasonality,and made it more difficult to establish effective population immunity. 展开更多
关键词 Human rhinovirus GENOTYPE Epidemical characteristics Respiratory infection Community-acquired pneumonia
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Use of evergreen and deciduous plants by nocturnal-roosting birds:A case study in Beijing
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作者 Yexi Zhao Jiayu Zhang +4 位作者 Zihan Li Qinmijia Xie Xin Deng Chenxi Zhang Nan Wang 《Avian Research》 SCIE CSCD 2024年第2期211-218,共8页
With continually increasing urbanization,the land cover in urban areas continues to change,resulting in the loss of biodiversity.Birds are highly sensitive to changes in habitat.Most forest birds perch on plants that ... With continually increasing urbanization,the land cover in urban areas continues to change,resulting in the loss of biodiversity.Birds are highly sensitive to changes in habitat.Most forest birds perch on plants that provide increased safety to reduce the risk of predation,and small birds may also consider insulation when using roosting plants in winter because of cold weather.Landscaping plants thus shape the nocturnal roosting environment of urban birds,and proper planting is essential for the survival of birds at night.The use of roosting plants by urban birds should therefore be studied to provide a reference for landscaping.In the current study,we observed 1865 nocturnal roosting birds in Beijing from 2021 to 2022,with 23 species of birds from 12 families and 45 species of plants from 22 families recorded.Juniperus chinensis exhibited the highest bird rarity-weighted richness,followed by Fraxinus pennsylvanica,Phyllostachys propinqua,Pinus tabuliformis,and Ulmus pumila.The diameter at breast height,tree height,and crown width of plants used by birds was largest in summer and smallest in winter,and the perch height of birds was the highest in spring and summer and the lowest in winter.Birds used the highest proportion of deciduous plants in summer and the highest proportion of evergreen plants in winter.A significant seasonal difference in the use of evergreen and deciduous plants by small birds was noted,with a preference for deciduous plants in summer and evergreen plants in winter,while this preference was not found in large birds.These findings indicate that evergreen plants provide a vital nocturnal roosting environment for small birds in winter.To provide a better nocturnal roosting habitat for urban birds,we recommend paying attention to the combination of evergreen and deciduous plants when carrying out landscape construction. 展开更多
关键词 Nocturnal roosting Roosting plant Seasonal variation Urban bird
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Active tectonic deformation and its seismic-geological significance of boundary faults of the Daxing Uplift and Langgu-Dachang Depression,Beijing Plain,China
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作者 Zheng Rong-Ying Yu Zhong-Yuan +2 位作者 Chen Bai-Xu Li Lu-Wei Wang Yi-Cheng 《Applied Geophysics》 SCIE CSCD 2024年第4期715-727,879,共14页
Boundary faults of the Daxing Uplift and Langgu-Dachang Depression are located in the southeastern region of the Beijing Plain and directly control the sedimentation,tectonic evolution,and strong seismic activity of t... Boundary faults of the Daxing Uplift and Langgu-Dachang Depression are located in the southeastern region of the Beijing Plain and directly control the sedimentation,tectonic evolution,and strong seismic activity of the plain.The Sanhe-Pinggu earthquake of Ms 8.0 occurred in 1679,but the active tectonic deformation characteristics of the boundary have been rarely discussed.In this study,the active tectonic deformation characteristics of the Daxing Uplift and Langgu-Dachang Depression boundary rupture were investigated by collecting and analyzing the results of previous works,supplementing three shallow-seismicexploration control lines at locations where the data are lacking,and carrying out borehole combined profile exploration and optically stimulated luminescence dating at local breakpoints.Results show that the Daxing Uplift and Langgu-Dachang Depression boundary faults constitute an active tectonic deformation zone with~50 km distance between Mafang and Niubaotun towns and then extends to both ends to form a deep and large fault that cuts through the earth’s crust.The activity of the Daxing Uplift eastern boundary fault may be divided into two sections near Anding town,with the early-to-middle Late Pleistocene gradually weakening in the northwest and the Holocene gradually weakening in the southwest.Moreover,the activity of the Xiadian fault may be divided into two sections near the Chaobai River:the Holocene gradually weakening in the northwest and the early-to-middle Late Pleistocene gradually weakening in the southwest.The boundary fault of the Daxing Uplift and Langgu-Dachang Depression has an~43 km seismic gap around Niubaotun town,which has a high risk of Ms 6.0-7.0 earthquakes.This investigation into the active tectonic deformation characteristics of the boundary fault of the Daxing Uplift and Langgu-Dachang Depression is crucial for analyzing the strong earthquake rupture behavior and the future risk of strong earthquakes in this area.It also contributes greatly to the study of the tectonic pattern evolution of the North China Plain and Beijing Plain. 展开更多
关键词 Daxing uplift Langgu-Dachang depression Active tectonic deformation Late Quaternary Strong earthquake risk
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Association between Exposure of Rare Earth Elements and Outcomes of In Vitro Fertilization-Embryo Transfer in Beijing
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作者 Yutong Wang Jing Li +9 位作者 Shirong Xu Shengli Lin Zhenchen Hou Linlin Wang Yali Huang Yue Sun Wei Guo Lailai Yan Ying Wang Chan Tian 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第8期876-886,共11页
Objective The study aimed to investigate the impact of rare earth elements(REEs)exposure on pregnancy outcomes of in vitro fertilization-embryo transfer(IVF-ET)by analyzing samples from spouses.Methods A total of 141 ... Objective The study aimed to investigate the impact of rare earth elements(REEs)exposure on pregnancy outcomes of in vitro fertilization-embryo transfer(IVF-ET)by analyzing samples from spouses.Methods A total of 141 couples were included.Blood and follicular fluid from the wives and semen plasma from the husbands,were analyzed for REEs using inductively coupled plasma mass spectrometry(ICP-MS).Spearman's correlation coefficients and the Mann–Whitney U test were used to assess correlations and compare REE concentrations among three types of samples,respectively.Logistic models were utilized to estimate the individual REE effect on IVF-ET outcomes,while BKMR and WQS models explored the mixture of REE interaction effects on IVF-ET outcomes.Results Higher La concentration in semen(median 0.089 ng/mL,P=0.03)was associated with a lower fertilization rate.However,this effect was not observed after artificial selection intervention through intracytoplasmic sperm injection(ICSI)(P=0.27).In semen,the REEs mixture did not exhibit any significant association with clinical pregnancy.Conclusion Our study revealed a potential association between high La exposure in semen and a decline in fertilization rate,but not clinical pregnancy rate.This is the first to report REEs concentrations in follicular fluid with La,Ce,Pr,and Nd found at significantly lower concentrations than in serum,suggesting that these four REEs may not accumulate in the female reproductive system.However,at the current exposure levels,mixed REEs exposure did not exhibit reproductive toxicity. 展开更多
关键词 Rare earth elements In vitro fertilization Pregnancy outcomes Mixture exposure analysis
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Prevalence,Characteristics and Treatment of Knee Osteoarthritis in Urban Residents of Beijing,China:A Community-Based Cross-Sectional Study
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作者 ZHOU Jun YAN Yan +8 位作者 DONG Ya Wei LIU Xiao Yu WANG Ping LIN Jia Ming DONG Peng Xuan QUAN Rui WANG Rong Tian MI Bao Hong CHEN Wei Heng 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第4期418-422,共5页
Knee osteoarthritis(KOA)is a common progressive joint disease with chronic pain and movement disorders as the main clinical features.It is a major public health problem worldwide and it imposes serious medical and eco... Knee osteoarthritis(KOA)is a common progressive joint disease with chronic pain and movement disorders as the main clinical features.It is a major public health problem worldwide and it imposes serious medical and economic burdens.KOA accounts for nearly four-fifths of the global Osteoarthritis burden and increases with rising obesity and age[1].There are many reasons for the change in disease prevalence and risk factors,such as urbanization,lifestyle changes,population aging,and sex imbalances. 展开更多
关键词 OSTEOARTHRITIS CLINICAL OBESITY
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Elimination Progress of Human Rabies in Beijing,1973-2023:A Descriptive Epidemiological Study
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作者 Tao Zhou Xiaomei Li +7 位作者 Cheng Gong Ming Luo Dan Zhao Jingbin Pan Ziang Li Quanyi Wang Luodan Suo Li Lu 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2024年第11期1338-1342,共5页
Rabies is a vaccine-preventable disease with a global goal of zero human deaths by 2030.However,this currently results in an annual loss of millions of disability-adjusted life years,particularly in developing countri... Rabies is a vaccine-preventable disease with a global goal of zero human deaths by 2030.However,this currently results in an annual loss of millions of disability-adjusted life years,particularly in developing countries[1].China experienced a peak in human rabies cases,with over 3,300 reported incidents in 2007.However,the subsequent implementation of robust measures,including enhanced animal management and Post-Exposure Prophylaxis(PEP),has led to a more than 90%reduction in rabies cases from 2007 to 2023[2].The epidemiological trend of human rabies in Beijing,the capital of China,has similarly undergone three stages since 1973.This study aimed to provide a comprehensive description of the observed epidemiological characteristics in Beijing from 1973 to 2023 and to assess the progress made toward elimination targets. 展开更多
关键词 RABIES VACCINE ELIMINATION
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