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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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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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ADDRESSING WATER SECURITY 3rd Asia International Water Week in Beijing
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作者 Gao Yuan 《China Report ASEAN》 2024年第10期35-36,共2页
Under the theme"Enhancing Our Future Water Security,"the3rd Asia International Water Week (3rd AIWW)commenced in Beijing on September 24.Li Guoying,Minister of Water Resources of China,delivered a keynote sp... Under the theme"Enhancing Our Future Water Security,"the3rd Asia International Water Week (3rd AIWW)commenced in Beijing on September 24.Li Guoying,Minister of Water Resources of China,delivered a keynote speech at the opening ceremony and signed the Beijing Declaration-Asia to World Statement of the Third Asia International Water Week with Seogdae Yun,president of the Asia Water Council. 展开更多
关键词 CEREMONY MINISTER beijing
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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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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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Ecological Carrying Capacity in Beijing Mountainous Areas——Taking Fangshan District as an Example 被引量:3
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作者 穆松林 张义丰 +2 位作者 唐承财 王灵恩 刘玉 《Agricultural Science & Technology》 CAS 2012年第11期2429-2433,共5页
[Objective] The aim was to investigate ecological carrying capacity of Fangshan District in Beijing. [Method] Ecological footprint and carrying capacity of Fangshan District in 2007 and 2008 were analyzed with ecologi... [Objective] The aim was to investigate ecological carrying capacity of Fangshan District in Beijing. [Method] Ecological footprint and carrying capacity of Fangshan District in 2007 and 2008 were analyzed with ecological footprint model and the difference between ecological footprint and carrying capacity there was con- cluded. Furthermore, an assessment was made on relation between Fangshan de- velopment with local ecological carrying capacity to evaluate sustainable development of Fangshan District. [Result] Fangshan District is of lightly ecological deficit; ecologi- cal footprint per capita in 2007-2008 was deficit and tended to expand. Two meth- ods are available to reduce ecological :deficit, including reduction of ecological foot- print and increase of carrying capacity. In general, supply and demand of carrying capacity in Fangshan are better, though with some problems. It is necessary to fur- ther develop related industries to final eliminate ecological deficit in order to achieve ecological conservation-orientation and sustainable development of Fangshan District. [Conclusion] The research provides theoretical references for overall evaluation on eco- logical carrying capacity of Fangshan District. 展开更多
关键词 Mountainous areas in beijing Ecological carrying capacity FangshanDistrict
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Old Beijing Hot Pot
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作者 周子宸 杨芳芳(指导) 《疯狂英语(双语世界)》 2024年第3期78-78,共1页
The origin of Old Beijing hot pot dates back to the Yuan Dynasty.It is said that Kublai Khan,during his expedition,craved his hometown cuisine.The chef had a clever idea:He cut lamb into slices,put them in a pot for a... The origin of Old Beijing hot pot dates back to the Yuan Dynasty.It is said that Kublai Khan,during his expedition,craved his hometown cuisine.The chef had a clever idea:He cut lamb into slices,put them in a pot for a quick rinse,and sprinkled some salt.Kublai Khan found it very delicious.This way of eating quickly spread,and the history of hot pot has been around for 700 years now. 展开更多
关键词 quickly beijing DYNASTY
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Fuwa:we are the mascots of the Beijing 2008 Olympic Games
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作者 唐协辉 《中学生英语(初中版)》 2008年第13期6-7,共2页
Time:2008Place:BeijingCharacters:Beibei,Jingjing,Huanhuan,Yingying,Nini,Some kids,Storyteller Scene I:We are FuwaStoryteller: Look,five lovely little friends—Fuwa are coming.
关键词 Fuwa:we are the mascots of the beijing 2008 Olympic Games 北京欢迎你
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Analysis on Vapour Field for the Drought Causes in Beijing,Tianjin and Hebei Districts in Recent Years 被引量:5
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作者 杨文霞 李宏宇 +1 位作者 李宗涛 房彬 《Agricultural Science & Technology》 CAS 2010年第1期117-121,共5页
The monthly variation,temporal-spatial distribution,transportation characteristics of vapour field at middle and lower atmosphere and their effects on drought in Beijing,Tianjin and Hebei districts were studied,which ... The monthly variation,temporal-spatial distribution,transportation characteristics of vapour field at middle and lower atmosphere and their effects on drought in Beijing,Tianjin and Hebei districts were studied,which have a guiding significance on predicting climate and arranging agricultural production in the district. 展开更多
关键词 beijing Tianjin and Hebei district DROUGHT Vapour field
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Counterdown Timer to Olympics:8 Measures to Promote Development of Beijing Exhibition Industry ——An interview towards Zhou Maofei, Chairman of Beijing Subcouncil, CCPIT
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《中国会展》 2005年第5期25-25,共1页
关键词 Counterdown Timer to Olympics Measures to Promote Development of beijing Exhibition Industry Chairman of beijing Subcouncil TIMER An interview towards Zhou Maofei CCPIT
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STRUCTURE DESIGN OF THE BEIJING SPECTROMETERⅢBEAM PIPE 被引量:3
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作者 ZHENG Lifang JI Quan +5 位作者 WANG Li LI xunfeng XU Shaowang DONG Sujun ZHAO Libin LIU Jianping 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2008年第3期1-6,共6页
The Beijing spectrometer Ⅲ (BESⅢ) beam pipe is in the center of the BESⅢ, which is the detector of the upgrade project of Beijing electron and positron collider (BEPC Ⅱ). Electrons and positrons collide in the... The Beijing spectrometer Ⅲ (BESⅢ) beam pipe is in the center of the BESⅢ, which is the detector of the upgrade project of Beijing electron and positron collider (BEPC Ⅱ). Electrons and positrons collide in the BESⅢ beam pipe. According to the demands of the BEPC Ⅱ, a key program of Chinese Academy of Sciences, the BESⅢ beam pipe is designed based on the finite elements analysis. The BESIII beam pipe is installed in the inner cylinder of the BESⅢ drift chamber. As a vacuum tube, the BESIII beam pipe is designed as 1 000 mm in length, 63 mm in inner diameter and 114 mm in outer diameter, respectively. The BESIII beam pipe consists of a central beryllium pipe cooled by EDM-1, the oil No.1 for electric discharge machining, and two extended copper pipes cooled by deionized water (DW). The three parts are jointed by vacuum welding. Factors taken into account in the design are as follows. ① The wall thickness of the central beryllium pipe should be designed as small as possible to reduce the multi-scattering and improve the particle momentum resolution. And the wall thickness of the extended copper pipe should be designed as large as possible to protect the detectors from the backgrounds. ②The BESⅢ beam pipe must be sufficiently cooled to avoid the damage and prevents its influence to the BESⅢ drift chamber (DC) operation. The inner surface temperature of the DC inner cylinder must be maintained at 293±2 K. ③ The magnetic permeability of the materials used in the BESⅢ beam pipe must be less than 1.05 H/m to avoid large magnetic field distortions. ④ The static pressure of the vacuum chamber of the BESⅢ beam pipe must be less than 800 μPa. The simulating results show that the designed structure of the BESⅢ beam pipe satisfies the requirements mentioned above. The structure design scheme is evaluated and adonted hv the headouarters of BEPCⅡ. 展开更多
关键词 Beam pipe beijing spectrometer Structure design beijing electron and positron collider BESⅢ
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Characteristics of soil seed bank in plantation forest in the rocky mountain region of Beijing, China 被引量:5
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作者 HU Zeng-hui YANG Yang +3 位作者 LENG Ping-sheng DOU De-quan ZHANG Bo HOU Bing-fei 《Journal of Forestry Research》 SCIE CAS CSCD 2013年第1期91-97,共7页
We investigated characteristics (scales and composition) of soil seed banks at eight study sites in the rocky mountain region of Beijing by seed identification and germination monitoring. We also surveyed the vegeta... We investigated characteristics (scales and composition) of soil seed banks at eight study sites in the rocky mountain region of Beijing by seed identification and germination monitoring. We also surveyed the vegetation communities at the eight study sites to explore the role of soil seed banks in vegetation restoration. The storage capacity of soil seed banks at the eight sites ranked from 766.26 to 2461.92 seeds·m?2. A total of 23 plant species were found in soil seed banks, of which 63–80% of seeds were herbs in various soil layers and 60% of seeds were located in the soil layer at 0–5 cm depth. Biodiversity indices indicated clear differences in species diversity of soil seed banks among different plant communities. The species composition of aboveground vegetation showed low similarity with that based on soil seed banks. In the aboveground plant community, the afforestation tree species showed high importance values. The plant species originating from soil seed banks represented natural regeneration, which also showed relatively high importance values. This study suggests that in the rocky mountain region of Beijing the soil seed banks played a key role in the transformation from pure plantation forest to near-natural forest, promoting natural ecological processes, and the role of the seed banks in vegetation restoration was important to the improvement of ecological restoration methods. 展开更多
关键词 Rocky mountain region of beijing soil seed bank plantcommunity plant diversity vegetation regeneration
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Cancer incidence in Beijing, 2014 被引量:12
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作者 Shuo Liu Lei Yang +5 位作者 Yannan Yuan Huichao Li Jing Tian Sijia Lu Ning Wang Jiafu Ji 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2018年第1期13-20,共8页
Objective: To analyze cancer incidence data in Beijing in 2014 and temporal trends for selected common cancers during 2005 and 2014.Methods: A total of 144 secondary and tertiary hospitals reported newly diagnosed c... Objective: To analyze cancer incidence data in Beijing in 2014 and temporal trends for selected common cancers during 2005 and 2014.Methods: A total of 144 secondary and tertiary hospitals reported newly diagnosed cancer cases to Beijing Cancer Registry, which covers 13 million residents in Beijing. The cancer incidence rate was calculated in strata by cancer type, sex, age group and area. The population composition of China in 1982 and Segi's population structure were used to calculate age-standardized rates. Extensive procedures were used to assure the quality of the data.Results: The overall data quality indicators of the percentage of morphology verification(MV)(%), the percentage of death certificate-only(DCO)(%) and the mortality to incidence ratio(M/I) were 72.15%, 0.94% and0.54 respectively. A total of 45,300 new cancer cases were diagnosed in Beijing in 2014. The incidence rate was341.92/100,000(343.50/100,000 in males, 340.33/100,000 in females), and the age-standardized incidence rates by Chinese standard population(ASIRC) and by world standard population(ASIRW) were 143.48/100,000 and182.99/100,000, respectively. The cumulative incidence rate for cancer before 75 years was 20.61%. Cancers of lung, colorectum, liver, stomach and prostate were the top five common cancer types for males, while cancers of breast, lung, thyroid, colorectum and uterus were the top five common cancer types for females. The different patterns were also observed between rural and urban areas. Regarding temporal trends, the incidence of thyroid cancer has the fastest growth between 2005 and 2014. The incidence of liver cancer decreased, and stomach and esophageal cancer also decreased significantly for males in the last decade. Incidence rate for lung cancer was relatively stable during that period of time.Conclusions: With more than 45,000 new cases in Beijing in 2014, cancer remains an important public health problem. Actions should be taken to diminish total cancer incidence in Beijing. 展开更多
关键词 Cancer incidence epidemiology beijing
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Dog-transmitted Rabies in Beijing, China 被引量:4
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作者 ZHANG Jing Yuan ZHANG Bi +4 位作者 ZHANG Shou Feng ZHANG Fei LI Nan LIU Ye HU Rong Liang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第7期526-529,共4页
Rabies remains a continuous threat to public health in Beijing. In this study, a total of 224 brain tissues were collected from suspected infected stray dogs within Beijing between January 2015 and December 2016. Amon... Rabies remains a continuous threat to public health in Beijing. In this study, a total of 224 brain tissues were collected from suspected infected stray dogs within Beijing between January 2015 and December 2016. Among them, total of 67 samples were diagnosed positive for rabies. In the phylogenetic analysis, rabies in Beijing is currently a relatively independent public health issue originating from local rabid dogs apart from the imported cases from elsewhere in the country. Because vaccination of unregistered dogs against rabies is still neglected in Beijing and other regions of China, national and local authorities should play central roles in all related aspects, such as development of policies, engagement of stakeholders for public and professional education, entire vaccination process, and animal management. 展开更多
关键词 in from IS of for China Dog-transmitted Rabies in beijing
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Measurement of respiration amount of white birch(Betula platyphylla)population in the mountainous region of Beijing 被引量:2
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作者 Fang Jingyun, Wang Xiaoke(Research Center for Eco - Environmental Sciences ,Chinese Academy of Sciences, Beijing 100085 , China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1995年第4期391-398,共8页
Measurementofrespirationamountofwhitebirch(Betulaplatyphylla)populationinthemountainousregionofBeijingFangJi... Measurementofrespirationamountofwhitebirch(Betulaplatyphylla)populationinthemountainousregionofBeijingFangJingyun,WangXiaoke(... 展开更多
关键词 diameter distribution mountainous region of beijing RESPIRATION white birch population.
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Upgrading a regional groundwater level monitoring network for Beijing Plain,China 被引量:9
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作者 Yangxiao Zhou Dianwei Dong +1 位作者 Jiurong Liu Wenpeng Li 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第1期127-138,共12页
Monitoring of regional groundwater levels provides important information for quantifying groundwater depletion and assessing impacts on the environment. Historically, groundwater level monitoring wells in Beijing Plai... Monitoring of regional groundwater levels provides important information for quantifying groundwater depletion and assessing impacts on the environment. Historically, groundwater level monitoring wells in Beijing Plain, China, were installed for assessing groundwater resources and for monitoring the cone of depression. Monitoring wells are clustered around well fields and urban areas. There is urgent need to upgrade the existing monitoring wells to a regional groundwater level monitoring network to acquire information for integrated water resources management. A new method was proposed for designing a regional groundwater level monitoring network. The method is based on groundwater regime zone mapping. Groundwater regime zone map delineates distinct areas of possible different groundwater level variations and is useful for locating groundwater monitoring wells. This method was applied to Beijing Plain to upgrade a regional groundwater level monitoring network. 展开更多
关键词 Groundwater monitoring Groundwater regime zone Monitoring network beijing Plain China
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Use of Cataract Surgery in Urban Beijing: a Post Screening Follow-up of the Elderly with Visual Impairment due to Age-related Cataract 被引量:5
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作者 Xue-tao Ren Torkel Snellingen +7 位作者 Hong Gu Sawitri Assanangkornchai Yan-hong Zou Virasakdi Chongsuvivatwong Apiradee Lim Wei Jia Xi-pu Liu Ning-pu Liu 《Chinese Medical Sciences Journal》 CAS CSCD 2015年第1期1-6,共6页
Objective To understand the perception for the use of cataract surgical services in a population acceptors and non-acceptors of cataract surgery in urban Beijing. Methods From a community-based screening program a to... Objective To understand the perception for the use of cataract surgical services in a population acceptors and non-acceptors of cataract surgery in urban Beijing. Methods From a community-based screening program a total of 158 patients with presenting visual acuity of less than 6/18 on either eye due to age-related cataract were informed about the possibility of surgical treatment. These patients were interviewed and re-examined 36 to 46 months after initial screening. The main reasons for not accepting surgery were obtained using a questionnaire. Vision function and vision-related quality of life scores were assessed in those who received and did not receive surgery. Results At the follow-up examination 116 of the 158 patients were available and 36 (31.0%) had undergone cataract surgery. Cases who chose surgery had higher education level than those who did not seek surgery (OR=2.64, 95% CI: 1.08-6.63, P=0.02). There were no significant differences in vision function (P=0.11) or quality of life scores (P=0.16) between the surgery group and the non-surgery group. Main reasons for not having surgery included no perceived need (50.0%), feeling of being "too old" (19.2%), and worry about the quality of surgery (9.6%). Cost was seeking surgery. cited by 1 (1.9%) subject as the main reason for not 展开更多
关键词 cataract surgery UTILIZATION urban beijing
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Occurrence of mycotoxins in feed ingredients and complete feeds obtained from the Beijing region of China 被引量:7
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作者 Xiaoying Li Lihong Zhao +6 位作者 Yu Fan Yaxiong Jia Lei Sun Shanshan Ma Cheng Ji Qiugang Ma Jianyun Zhang 《Journal of Animal Science and Biotechnology》 SCIE CAS 2014年第4期471-478,共8页
Background:The current study was carried out to provide a reference for the control of mycotoxin contamination in feed ingredients and complete feeds for swine.Methods:A total of 55 feed ingredients,including 14 cor... Background:The current study was carried out to provide a reference for the control of mycotoxin contamination in feed ingredients and complete feeds for swine.Methods:A total of 55 feed ingredients,including 14 corn,13 wheat bran,11 soybean meal and 17 dried distillers grains with solubles(DDGS) as well as 76 complete swine feeds including 7 creep feeds,14 starter feeds,14 grower feeds,18 grower-finisher feeds,10 gestating sow feeds,and 13 lactating sow feeds were randomly collected from15 swine farms located in the Beijing region of China from July to August 2011.Immunoaffinity clean-up,using High-Performance Liquid Chromatography(HPLC) in combination with UV or Fluorescence Detection,was used for quantitative analysis of aflatoxin B,(AFB,),deoxynivalenol(DON),zearalenone(ZEA) and ochratoxin A(OTA) in the ingredients and complete feeds.Results:DON and ZEA were the most prevalent mycotoxins found.DON was detected at percentages of 93,92,54,100 and 97%with a mean level of 1.01,0.44,0.05,1.36 and 0.65 ppm in the samples of corn,wheat bran,soybean meal,DDGS and complete feeds,respectively.The detected percentages of ZEA were 100,100,54,100 and 100 with mean levels of 109.1,14.9,9.2,882.7 and 58.9 ppb in the same samples.In the wheat bran and soybean meal samples,the content of all four mycotoxins were below the maximum limits set by Chinese regulations while the percentage of samples that exceeded regulatory limits were 7,57 and 7%for corn,and 7,14 and 3%for the complete feeds for AFB,,DON and OTA respectively.DDGS showed the most serious mycotoxin contamination and the percentage of samples that exceeded regulatory limits were 6,88 and 41%,for AFB,,DON and ZEA,respectively.Conclusions:This paper is the first to present data on the natural occurrence of AFB,,DON,ZEA and OTA in ingredients and complete feeds obtained from swine farms in China's Beijing region.The data shows that feed ingredients and complete swine feeds obtained from these farms are most often contaminated with DON followed by contamination with AFB,and ZEA. 展开更多
关键词 AflatoxinB1 beijing region Deoxynivalenol Ochratoxin A Swine feeds Zearalenone
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Ambient noise as the new source for urban engineering seismology and earthquake engineering: a case study from Beijing metropolitan area 被引量:8
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作者 Lanbo Liu Qi-fu Chen +1 位作者 Weijun Wang Eric Rohrbach 《Earthquake Science》 2014年第1期89-100,共12页
In highly populated urban centers, traditional seismic survey sources can no longer be properly applied due to restrictions in modern civilian life styles. The ambient vibration noise, including both microseisms and m... In highly populated urban centers, traditional seismic survey sources can no longer be properly applied due to restrictions in modern civilian life styles. The ambient vibration noise, including both microseisms and microtremor, though are generally weak but available anywhere and anytime, can be an ideal supplementary source for conducting seismic surveys for engineering seismology and earthquake engineering. This is funda- mentally supported by advanced digital signal processing techniques for effectively extracting the useful information out from the noise. Thus, it can be essentially regarded as a passive seismic method. In this paper we first make a brief survey of the ambient vibration noise, followed by a quick summary of digital signal processing for passive seismic surveys. Then the applications of ambient noise in engi- neering seismology and earthquake engineering for urban settings are illustrated with examples from Beijing metro- politan area. For engineering seismology the example is the assessment of site effect in a large area via microtremor observations. For earthquake engineering the example is for structural characterization of a typical reinforced con- crete high-rise building using background vibration noise.By showing these examples we argue that the ambient noise can be treated as a new source that is economical, practical, and particularly valuable to engineering seis- mology and earthquake engineering projects for seismic hazard mitigation in urban areas. 展开更多
关键词 Ambient noise Resonance frequency -Ground motion amplification Seismic vulnerability ~Horizontal to vertical spectra/ratio (HVSR) ~Seismic interferometry (SI) ~ beijing metropolitan area
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Effect of urbanization on the abundance and distribution of Tree Sparrows (Passer montanus) in Beijing 被引量:3
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作者 张淑萍 郑光美 《Chinese Birds》 2010年第3期188-197,共10页
With rapid urbanization occurring throughout China,the existence of Tree Sparrows (Passer montanus) in big cities is likely to be affected by a decrease in habitat and food availability.Can the urban Tree Sparrow adap... With rapid urbanization occurring throughout China,the existence of Tree Sparrows (Passer montanus) in big cities is likely to be affected by a decrease in habitat and food availability.Can the urban Tree Sparrow adapt to these changes? To elucidate this question,we studied the effect of urbanization on the abundance and distribution of Tree Sparrows in Beijing.We found the abundance of the Tree Sparrow negatively correlated with an urbanization score.Sparrow abundance was very low in residential areas with high-rise buildings,commercial centers and main roads,while their numbers were significantly higher in parks,university campuses,low building residential and suburban areas.Environmental factors within the 50 m and 200 m scales were most suitable in predicting the distribution of Tree Sparrows during winter,while factors within 50 m and 400 m scales are suitable during the breeding season.During winter,the number of conifer trees and pedestrians were the major factors at the 50 m scale,while the area of high-rise buildings and vegetation become the predominant factors on a 200 m scale.Alternatively,during the breeding season the area of low buildings and the number of conifers and pedestrians were the main factors on the 50 m scale while the area of high-rise buildings and vegetation remained the most important factors on the 400 m scale.These results indicate that highly urbanized areas are not suitable habitats for the Tree Sparrow,although this species can adapt to human environments.Food and nest sites for urban birds should be considered in urban planning of big cities in developing countries. 展开更多
关键词 URBANIZATION Tree Sparrow (Passer montanus) ABUNDANCE DISTRIBUTION beijing
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