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New cheaper human papilloma virus mass screening strategy reduces cervical cancer incidence in Changsha city:A clinical trial
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作者 Yue-E Zu Si-Feng Wang +7 位作者 Xing-Xing Peng Yong-Chun Wen Xue-Xiang Shen Xiao-Lan Wang Wen-Bo Liao Ding Jia Ji-Yang Liu Xiang-Wen Peng 《World Journal of Clinical Oncology》 2024年第12期1491-1500,共10页
BACKGROUND Cervical cancer is the second leading cause of death in women worldwide,second only to breast cancer.Around 80%of women have been infected with human papillomavirus(HPV)in their lifetime.Early screening and... BACKGROUND Cervical cancer is the second leading cause of death in women worldwide,second only to breast cancer.Around 80%of women have been infected with human papillomavirus(HPV)in their lifetime.Early screening and treatment are effective means of preventing cervical cancer,but due to economic reasons,many parts of the world do not have free screening programs to protect women’s health.AIM To increase HPV cervical cancer screening in Changsha and reduce the incidence of cervical cancer.METHODS Cervical cancer screening included gynecological examination,vaginal secretion examination and HPV high-risk typing testing.Cervical cytology examination(ThinPrep cytology test)was performed for individuals who test positive for HPV types other than 16 and 18.Vaginal colposcopy examination was performed for HPV16 and 18 positive individuals,as well as for those who were positive for ThinPrep cytology test.If the results of vaginal colposcopy examination were abnormal,histopathological examination was performed.We conducted a cost-benefit analysis after 4 years.RESULTS From 2019 to 2022,523437 women aged 35-64 years in Changsha city were screened and 73313 were positive,with a 14%positive rate.The detection rate of precancerous lesions of cervical cancer was 0.6%and the detection rate of cervical cancer was 0.037%.Among 311212 patients who underwent two cancers examinations,the incidence rate was reduced by more than half in the second examination.The average screening cost per woman was 120 RMB.The average cost of detecting early cases was 10619 RMB,with an early detection cost coefficient of 0.083.CONCLUSION Our screening strategy was effective and cost-effective,making it valuable for early diagnosis and treatment of cervical cancer.It is worth promoting in economically limited areas. 展开更多
关键词 Cervical cancer screening Human papillomavirus ThinPrep cytology test COST-EFFECTIVE New cheaper screening strategy
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Analysis on the Cause and Forecast Deviation of an Extreme Rainstorm in Changsha Urban Area
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作者 Yun FANG Tianyao SHEN +2 位作者 Sheng ZHOU Jingjing PENG Lijun CHENG 《Meteorological and Environmental Research》 CAS 2023年第1期50-55,59,共7页
Using NCEP reanalysis data,high-altitude and ground observation data,numerical model data,satellite and radar data,formation cause and forecast deviation of an extreme rainstorm process in Changsha urban area at night... Using NCEP reanalysis data,high-altitude and ground observation data,numerical model data,satellite and radar data,formation cause and forecast deviation of an extreme rainstorm process in Changsha urban area at night on June 9,2020 were analyzed.The results showed that(1)the extreme rainstorm process developed near the surface convergence line,with strong localization,short duration and large hourly rainfall intensity.(2)Under the high temperature and high humidity environment,the low-level cold advection and the hot low-pressure system interacted,and the potential con-vective unstable energy was released,and a strong convective weather was formed.(3)The convergence of water vapor in the lower layer and the strong upward movement provided sufficient water vapor for the rainstorm.The low-centroid thunderstorm was the main reason for the extreme rainstorm.(4)The forecast deviation of the numerical model to the low-level shear line and the mesoscale convergence line was an important reason for the forecast deviation of the heavy rainfall area. 展开更多
关键词 Extreme rainstorm Ground convergence line Unstable energy
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Geospatial-Based Analysis of Balance in Elementary Education—Taking Elementary Schools in Changsha Five Core Districts as Examples
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作者 Bin Yan Shiyuan Zhou 《Open Journal of Applied Sciences》 2023年第8期1276-1288,共13页
The balanced development of the elementary education sector has been a long goal pursued by the education departments of various places, and is also an outcome expected by the people. Based on a study of the equilibri... The balanced development of the elementary education sector has been a long goal pursued by the education departments of various places, and is also an outcome expected by the people. Based on a study of the equilibrium of the spatial distribution of the capacity saturation models of all the primary schools in Changsha’s (China) five core districts, the results show that the overall geographical distribution of the primary schools in Changsha is relatively balanced, based on the natural characteristics of Changsha, such as human geography, and the moderate gradient between the central urban area and the primary schools in the suburbs and outer suburbs. Then the Theil index model was introduced, and the results of the model analysis show that the differences between elementary schools in Changsha urban area are relatively small, and the main differences originate from between districts rather than within districts, and subtle differences among regions mainly reflect in the teacher strength. 展开更多
关键词 GEOSPATIAL Education Balance Development Primary School Theil Index
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The influencing factors of urban land expansion in Changsha 被引量:9
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作者 ZHOU Guohua HE Yanhua 《Journal of Geographical Sciences》 SCIE CSCD 2007年第4期487-499,共13页
This research systematically analyses land-use map of Changsha city in different periods of time. The spatial form and structural evolution was analysed by studying indices such as city land-use structure proportion, ... This research systematically analyses land-use map of Changsha city in different periods of time. The spatial form and structural evolution was analysed by studying indices such as city land-use structure proportion, expansion intensity, economic flexibility, population flexibility, changing compactness index and so on. The dynamic mechanism of urban land expansion has been discussed by integrating the regional social economy development situation and many aspects such as the physiographical surrounding, population and economic development, traffic infrastructure, planning and regional development tactic and system innovation. The research indicates that the urban land expansion speed and intensity have steadily increased in Changsha from 1949 to 2004. The expansion form has been from a single external expansion to a combination form of external and internal expansion, from a circular or linear continuous form to a blocky or agglomeration shape. Overall, the urban land expansion of Changsha city is a phasic, diversified and complex process. And no matter what the stage is, it is an organic system containing multiple speed, pattern and shape, which are driven by multiple impetuses. The dominant feature at different stages was highlighted because of the balance and fluctuation between different forces, and the existing urban land border and shape have resulted from the joint efforts of these phasic forces. 展开更多
关键词 Changsha urban land expansion influencing factors dynamic mechanism
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Modelling urban expansion using a multi agentbased model in the city of Changsha 被引量:12
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作者 ZHANG Honghui ZENG Yongnian +1 位作者 BIAN Ling YU Xijun 《Journal of Geographical Sciences》 SCIE CSCD 2010年第4期540-556,共17页
Although traditional urban expansion simulation models can simulate dynamic features, these models fail to address complex changes produced by different agents' behaviors. The paper has built up a set of spatial-temp... Although traditional urban expansion simulation models can simulate dynamic features, these models fail to address complex changes produced by different agents' behaviors. The paper has built up a set of spatial-temporal land resource allocation rules and developed a dynamic urban expansion model based on a multi-agent system, which can simulate the interaction among different agents, such as residents, peasants, and governments. This model is applied to simulate urban expansion process taking Changsha City, in China as a study area. The results show that this model can not only reflect basic characteristics of urban expansion, but also help explain the reasons for urban expansion process and understand the effect of agents' behavior on the expansion process, and provide insights into the causing factors behind the expansion. In addition, in contrast to simulation results with land use classification map from remote sensing images, the precision of the simulation reached over 68% with higher precision than cellular automata model according to the cell-by-cell comparison. The results suggest that the model can help to provide land use decision making support to government and urban planners. 展开更多
关键词 multi-agent system cellular automata urban expansion land resource allocation Changsha
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Spatiotemporal Measurement of Regional Expansion in Changsha-Zhuzhou-Xiangtan Metropolitan Area Based on Nighttime Light Data 被引量:3
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作者 Jian Zheng Guoguang Wang Hua Wang 《Journal of Geographic Information System》 2020年第3期202-220,共19页
The research purpose is to accurately reveal the temporal and spatial law of the urban expansion of Changsha-Zhuzhou-Xiangtan, one of the seven major urban agglomeration areas in China, and provide decision-making bas... The research purpose is to accurately reveal the temporal and spatial law of the urban expansion of Changsha-Zhuzhou-Xiangtan, one of the seven major urban agglomeration areas in China, and provide decision-making basis for the future urban construction land layout and regional development policy-making. Based on the night lighting data (DMSP/OLS), this paper extracts the boundary of the urban construction land of Changsha-Zhuzhou-Xiangtan urban agglomeration from 1993 to 2017, and quantitatively studies the spatial and temporal characteristics of the expansion of the metropolitan area in the past 25 years according to the methods of spatial expansion analysis, center of gravity migration measurement, landscape pattern index, spatial autocorrelation, etc. The results show that: 1) it is scientific and feasible to extract urban agglomeration construction land by the method of auxiliary data comparison for the study of urban expansion;2) the expansion of regional space in Changsha-Zhuzhou-Xiangtan metropolitan area shows a trend of “weakening first and strengthening later”. The construction land keeps increasing, and the expansion form gradually changes from extensive type to intensive type;3) the center of gravity of the metropolitan area fluctuated and repeated in part during the past 25 years, but it was always located in the municipal district of Changsha city. The eastern region, mainly Changsha city, was still the core area of urban agglomeration expansion;4) strengthening the territorial space protection and control of ecological green core in the metropolitan area is a key measure for the high-quality development of urban agglomeration. 展开更多
关键词 Changsha-Zhuzhou-Xiangtan Spatial Expansion Nighttime Light Data Metropolitan Area Control Scenario
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The Land Management Pattern in " Green Heart" Area——A Case Study of Changsha-Zhuzhou-Xiangtan Urban Agglomeration 被引量:1
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作者 LU Yi-chuan DUAN Jian-nan 《Asian Agricultural Research》 2012年第2期31-34,38,共5页
By analyzing the status quo of land resources in " green heart" area of Changsha-Zhuzhou-Xiangtan urban agglomeration,and problems existing in land management,this article puts forward some countermeasures a... By analyzing the status quo of land resources in " green heart" area of Changsha-Zhuzhou-Xiangtan urban agglomeration,and problems existing in land management,this article puts forward some countermeasures and proposals as follows:establish new land management mechanism in " green heart" area;based on land planning," green heart" overall planning and policies and regulations,manage land and promote the protection of urban ecological environment. 展开更多
关键词 'Green heart' Land management Land use'Ecology'Changsha-Zhuzhou-Xiangtan urban agglomeration
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Study on Relationship between Summer Electricity and Meteorology in Changsha City
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作者 Zhuqing Zhang Zhengcai Huang +1 位作者 Qingdong Qiu Mengshuang Peng 《Meteorological and Environmental Research》 CAS 2013年第5期20-25,29,共7页
[ Objective] The research aimed to study relationship between summer electricity and meteorological factors. [ Method] Electrical load characteristics in Changsha during 2007 -2010 were analyzed. Correlation analysis ... [ Objective] The research aimed to study relationship between summer electricity and meteorological factors. [ Method] Electrical load characteristics in Changsha during 2007 -2010 were analyzed. Correlation analysis between electrical load and meteorological factors (daily average temperature, the maximum temperature, the minimum temperature, rainfall, wind, relative humidity and atmospheric pressure) during July - September of 2007 -2010 was conducted. [ Result] Changes of the meteorological factors could directly affect electrical load, and temperature was the first influence factor. Prediction model of summer electrical load in Changsha was established by regression analysis method.[ Conclusion] The research could provide reference basis for prediction of the electrical load in Changsha. 展开更多
关键词 Changsha Electrical load Meteorological factor Prediction model China
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Surface water quality and potential health risk assessments in Changsha-Zhuzhou-Xiangtan section of Xiangjiang River, China 被引量:7
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作者 JIANG Dong-yi YANG Jin-qin +3 位作者 WANG Yun-yan LIAO Qi LONG Zhe ZHOU San-yang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第12期3252-3260,共9页
The Changsha-Xiangtan-Zhuzhou City Group is a heavy industrial district and accepted as the serious pollution area in the Xiangjiang River basin.In this study,7 metals(Pb,Hg,Cd,As,Zn,Cu and Se)and the river water qual... The Changsha-Xiangtan-Zhuzhou City Group is a heavy industrial district and accepted as the serious pollution area in the Xiangjiang River basin.In this study,7 metals(Pb,Hg,Cd,As,Zn,Cu and Se)and the river water quality parameters including pH,dissolved oxygen(DO),Escherichia coli(E.coli),potassium permanganate index(CODMn),dichromate oxidizability(CODCr),five-day biochemical oxygen demand(BOD5),ammonia nitrogen(NH4+-N),total nitrogen(TN),total phosphorus(TP)and fluoride(F)in 18 sampling sites of the Changsha-Xiangtan-Zhuzhou section are monthly monitored in 2016,which is the year to step into the second stage of the“Xiangjiang River Heavy Metal Pollution Control Implementation Plan”.It is found that E.coli,TN and TP are the main pollutants in the Changsha-Zhuzhou-Xiangtan section,and the pollution of heavy metal is not serious but As with potential risk to local people especially children should be concerned.In addition,Xiangtan city is mainly featured with heavy metal pollution,while Zhuzhou and Changsha city are both featured with other pollutants from municipal domestic sewage. 展开更多
关键词 Xiangjiang River surface water heavy metal water quality assessment human health risk assessment
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Phosphorus Status and Risk of Phosphate Leaching Loss From Vegetable Soils of Different Planting Years in Suburbs of Changsha, China 被引量:15
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作者 QIN Hong-ling QUAN Zhi +4 位作者 LIU Xin-liang LI Ming-de ZONG Yong WU Jin-shui WEI Wen-xue 《Agricultural Sciences in China》 CSCD 2010年第11期1641-1649,共9页
The aim of the study was to develop an index to assess the environmental risk of P loss potential in vegetable soils with chronic difference of plantation in the suburbs of Changsha, Hunan Province, China. Chemical me... The aim of the study was to develop an index to assess the environmental risk of P loss potential in vegetable soils with chronic difference of plantation in the suburbs of Changsha, Hunan Province, China. Chemical methodology was used to study soil phosphorus status and the relationships between available P in soil and potential soil leaching P. The results showed that there was a significant linear relationship between Olsen P and CaC12-P or P concentration in soil solution. Olsen P increased sharply when either CaCI2-P or P concentration in soil solution reached a certain level. It was confirmed that 80 mg kg-t of Olsen P was the critical value of soil P leaching in the vegetable soils. P leaching probability over the critical was assessed by GIS and indicator Kriging and four secondary risks of phosphorus leaching loss were defined. In the area with vegetable cropping for over 30 yr (Chenjiadu) and 10-15 planting years (Huangxingzhen), the indices of phosphorus leaching loss risk were 3 and 2.93, respectively. These two areas belonged to strong secondary of risk of phosphate leaching loss. In the new vegetable planting field less than 2 yr (Ningxiang), the index was 0.06, which had almost no risk of phosphorus leaching. In vegetable soils in the suburban region of Changsha, the phosphorus leaching peotential is high and the phosphorus leaching loss is related to chronic length of vegetable cropping. 展开更多
关键词 vegetable soils critical value P leaching probability risk assessment
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Route evaluation indexes of Changsha-Jishou freeway for protecting cultural heritages and natural environment 被引量:1
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作者 ZHANG Ying-xue LIU Zhao-hui 《Journal of Environmental Science and Engineering》 2009年第3期56-63,共8页
The highway construction inevitably may cause certain influence to the cultural heritage and the natural environment along the route, particularly in design stage; if the route selection is unreasonable, it will certa... The highway construction inevitably may cause certain influence to the cultural heritage and the natural environment along the route, particularly in design stage; if the route selection is unreasonable, it will certainly impact the natural resource seriously along the route. On the contrary, good design can reasonably develop, use, protect and promote the value of cultural heritage and natural environment. Changsha to Jishou (Chang-Ji) freeway is one section of Changsha to Chongqing freeway, which is one of the eight big west channels as planned in China; two cities of Changde and Huaihua and one autonomous region of Xianxi in western Hunan province, along which the cultural heritage and the natural resource are rich, and the natural landscape is exquisite. This paper investigates and analyzes the natural resources along the route of Chang-Ji freeway, puts forward some protection design evaluation indexes for mountain area freeway by the thought of context sensitive design. At last, the paper introduces the effect of applying the indexes to select route of Chang-Ji freeway. 展开更多
关键词 FREEWAY context sensitive design cultural heritage natural environment route selection
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Application of New Type of Detection Data in a Heavy Rainfall Process in Changsha
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作者 Huo Tao Shan Nan +2 位作者 Tang Xiaonan Fan Yu Liu Daxin 《Meteorological and Environmental Research》 CAS 2019年第4期37-38,41,共3页
Using detection data with high space-time resolution from the wind profile radar and millimeter wave cloud radar of Changsha station, and combining observation data of ground automatic station, heavy precipitation pro... Using detection data with high space-time resolution from the wind profile radar and millimeter wave cloud radar of Changsha station, and combining observation data of ground automatic station, heavy precipitation process in Changsha area from June 29 to July 1, 2017 was analyzed. The results showed that the atmospheric temperature advection was calculated by inversion of wind profile radar data of boundary layer, and it could intuitively analyze changes of atmospheric temperature advection before and after precipitation process. The variation characteristics of intensity, thickness and height of warm and cold advection in the upper and lower levels were highly related to the evolution of the precipitation process. The millimeter wave cloud radar can better reflect the vertical structure and evolution of the cloud over the observatory, and had certain indications for the structure characteristics of cloud before the starting of precipitation. When the strong reflectivity started to approach the ground, it also meant that heavy precipitation began to appear. 展开更多
关键词 WIND profile RADAR MILLIMETER wave CLOUD RADAR Temperature advection
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Research on Influence Factors of Landscape Health of National Wetland Park from Tourists' Perspective:A Case Study of Changsha Yanghu National Wetland Park
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作者 YANG Li ZHANG Yiqiong 《Journal of Landscape Research》 2022年第4期53-56,60,共5页
This paper designed the index system for the evaluation of landscape health influence factors of Yanghu Wetland Park from tourists’ perspective,applied the principal component method to extract 19 indexes of 5 public... This paper designed the index system for the evaluation of landscape health influence factors of Yanghu Wetland Park from tourists’ perspective,applied the principal component method to extract 19 indexes of 5 public factors,i.e.policy system,ecological environment,functional management,landscape facility,tourists’ behavior,to analyze the influence factors for the landscape health of national wetland parks.The results showed that tourists’ evaluation varied greatly on the significance of 19 indexes and their satisfaction in the influence factor system of landscape health,then used IPA modified model to classify the factors influencing landscape health of Yanghu Wetland Park into 4 categories,defined the orientation of the 19 indexes in the 4 categories,and proposed the corresponding landscape health optimization strategies based on the analysis results of IPA modified model. 展开更多
关键词 Yanghu Wetland Park Landscape health IPA modified model Optimization strategy
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Positioning and function of secondary general hospital in community rehabilitation of disabled persons-a case study of a secondary general hospital in Changsha city
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作者 Jin Song Zhichun Zhu Kesheng Zhang 《Journal of Translational Neuroscience》 2021年第3期12-18,共7页
Objective:the positioning of secondary hospitals in the community rehabilitation work system and the status of community medical rehabilitation ser-vices for the disabled in Changsha were clarified through investigati... Objective:the positioning of secondary hospitals in the community rehabilitation work system and the status of community medical rehabilitation ser-vices for the disabled in Changsha were clarified through investigation and study of the 2019 income of a second-ary general hospital in Changsha.Suggestions from var-ious parties were integrated to provide feasible ideas for expanding the role of secondary hospitals in community rehabilitation.Methods:the 2019 income of a secondary general hospital in Changsha was statistically analyzed,a community rehabilitation questionnaire was designed,and a field survey was carried out focusing on 19 issues including rehabilitation service items,rehabilitation facil-ities and equipment,and the satisfaction of rehabilitation practitioners.Results:in the total hospitalization expenses of a secondary general hospital in Changsha city in 2019,rehabilitation physiotherapy expenses accounted for 7%,and drug treatment expenses accounted for 25%.In addi-tion,in the survey of community rehabilitation service sat-isfaction for the disabled,the difference between the very dissatisfied and very satisfied groups was statistically sig-nificant(P<0.05).Conclusion:taking a secondary gener-al hospital in Changsha city as an example,the treatment methods in secondary general hospitals are still dominated by traditional drug therapy,and the disabled are not sat-isfied with community rehabilitation services.Therefore,rehabilitation treatment projects to meet the rehabilitation needs of the disabled should be promoted in hospitals. 展开更多
关键词 secondary public hospital community rehabilitation POSITIONING people with disabilities
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Characteristics Analysis of the Temperature inside and outside the Themometer Shelter in Changsha during Summer
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作者 Chen Zhaohui Fan Yu 《Meteorological and Environmental Research》 CAS 2014年第11期13-18,共6页
A statistical analysis on the simultaneous observation data of the temperature inside and outside the themometer shelter in Changsha during summer of 2011 and 2012 was carried out. The results show that the temperatur... A statistical analysis on the simultaneous observation data of the temperature inside and outside the themometer shelter in Changsha during summer of 2011 and 2012 was carried out. The results show that the temperature outside the themometer shelter is higher( lower) than that inside the themometer shelter in the daytime( nighttime). However,there exists a similar variation trend for the average temperature and the extremely maximum temperature inside and outside the themometer shelter in summer. The average temperature and the extremely maximum temperature outside the themometer shelter are higher than that inside the themometer shelter. Furthermore,there exists a difference between the temperatures inside and outside the themometer shelter during different weather conditions. The difference of average temperature reaches 1. 2 ℃ in rainy day,2. 8 ℃ in cloudy day and 3. 1 ℃ in sunny day,and the extremely maximum temperature difference reaches 6. 4 ℃. Especially for the days of high temperature ≥35 ℃,there is 61 high temperature days inside the themometer shelter,while there is 125 high temperature days inside the themometer shelter during 2011- 2012. Furthermore,the extremely maximum temperatures inside and outside the themometer shelter are 38. 9 and42. 0 ℃ respectively. Rainfall and showery rain are the most effective ways to relieve the high temperature in summer. Therefore,the difference between the temperatures inside and outside the themometer shelter should be taken into account in the high temperature forecast and public meteorological service. 展开更多
关键词 Temperature inside and outside the themometer shelter Summer Characteristics analysis China
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Establishment of a donor pig for xenotransplantation clinical trials based on the principle of Changsha Communiqué
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作者 Xiaoqian Ma Sang Li +2 位作者 Jia Wang Chang Xu Wei Wang 《Health Care Science》 2023年第2期129-134,共6页
Background:Xenotransplantation is a potential way to reduce the shortage of the needed organ grafts for the end-stage disease.Immune rejection,physiological incompatibility and bio-safety are the most critical issues.... Background:Xenotransplantation is a potential way to reduce the shortage of the needed organ grafts for the end-stage disease.Immune rejection,physiological incompatibility and bio-safety are the most critical issues.Methods:To ensure the safety and efficacy of gene editing,second-and thirdgeneration sequencing technologies have allowed us to obtain a clearer genetic background of donor pigs for xenotransplantation.Based on the Changsha Communiqué,the local DPF-excluded lists and DPF donor facility were established in Changsha,China.A pig-to-human islet clinical trial was conducted and overseen by the respective Chinese governmental agency.Results:The DPF standards for pig husbandry eliminated specific pathogens in donor pigs.We have established a PERV-C free,genetic information clean,DPF donor for xenotransplantation.A clinical trial of ten adult patients(9M:1F)with type 1 diabetes who received DPF porcine islet xenotransplantation via the portal vein were performed.Clinical accepted immunosuppressant drugs and autologous Treg were used for controlling immune rejection.No cross-species infection events occurred in this trial,and importantly,no cross-species transmission of PERV was found.Conclusions:Xenotransplantation is a pioneer study and safety is the most important issue.The fundamental principles for establishing xenotransplantation donor pigs should follow the Changsha Communiqué(2008),the second WHO consultation,and the 2018 Changsha Communiquéwhich would finally help reducing the risks of xenotransplantation. 展开更多
关键词 bio-safety donor pig DPF xenotransplantation
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不同时长运动预处理对血管性痴呆大鼠脑血流量及小胶质细胞活化相关蛋白的影响 被引量:3
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作者 唐鑫 陈婕 +6 位作者 田浩梅 张泓 邹莹洁 谢紫薇 陈盼 谢海花 谭洁 《中国康复医学杂志》 CAS CSCD 北大核心 2024年第1期15-23,共9页
目的:探讨不同时长运动预处理对血管性痴呆大鼠脑血流量变化及小胶质细胞活化相关蛋白的影响。方法:选用60只SPF级SD雄性大鼠,采用双侧颈总动脉永久性结扎法制备血管性痴呆大鼠模型,随机分为模型组、假手术组、运动预处理4周模型组、运... 目的:探讨不同时长运动预处理对血管性痴呆大鼠脑血流量变化及小胶质细胞活化相关蛋白的影响。方法:选用60只SPF级SD雄性大鼠,采用双侧颈总动脉永久性结扎法制备血管性痴呆大鼠模型,随机分为模型组、假手术组、运动预处理4周模型组、运动预处理4周假手术组、运动预处理2周模型组及运动预处理2周假手术组,每组10只。运动预处理4周大鼠在造模前每周行5次中等强度不负重游泳训练30min,持续4周,而运动预处理2周大鼠持续2周。利用Morris水迷宫检测大鼠空间学习记忆能力、激光散斑成像技术检测各组大鼠造模前后不同时间点脑血流变化及侧支循环开放情况、Western Blot技术检测海马TLR4及Iba1蛋白表达情况。结果:与假手术组、运动预处理2周假手术组相比,运动预处理4周假手术组、模型组、运动预处理4周模型组及运动预处理2周模型组大鼠平均逃避潜伏时延长(P<0.05)。与运动预处理4周假手术组相比,模型组、运动预处理4周模型组大鼠平均逃避潜伏时延长(P<0.05)。与模型组、运动预处理4周模型组相比,运动预处理2周模型组大鼠平均逃避潜伏时缩短(P<0.05)。重复测量方差分析简单效应提示造模前、造模后2h、造模后3d及造模后7d各组间平均脑血流量差异具有显著性意义(P<0.05)。模型组、运动预处理4周模型组及运动预处理2周模型组时间因素对平均脑血流量的简单效应具有显著性意义(P<0.01)。对各组大鼠侧支循环开放进行观察,相较于模型组,于运动预处理2周模型组观察到更少的微血管直径减少(P<0.05)。与假手术组、运动预处理4周假手术组及运动预处理2周假手术组相比,模型组Iba1、TLR4蛋白表达明显上升(P<0.01),与模型组相比,运动预处理2周模型组Iba1、TLR4蛋白表达下降(P<0.05)。结论:中等强度运动预处理2周可改善血管性痴呆大鼠学习记忆能力,运动预处理4周对学习记忆能力改善效应不明显,其机制可能与改善脑血流状态以及抑制小胶质细胞活化有关。 展开更多
关键词 运动预处理 血管性痴呆 脑血流量 小胶质细胞
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湖南耕地土壤和稻米重金属污染防控实践与思考 被引量:3
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作者 雷鸣 周一敏 +6 位作者 黄大睿 黄雅媛 王薪琪 李冰玉 杜辉辉 刘孝利 铁柏清 《地学前缘》 EI CAS CSCD 北大核心 2024年第2期173-182,共10页
湖南省是我国主要产粮区之一。由于矿产经济活动及其他人类活动,大面积耕地土壤受到重金属污染,从而一些地方的稻米重金属含量超过国家食品卫生标准。本研究对湖南省耕地土壤与稻米重金属污染现状和成因进行剖析。结果表明:湖南耕地土... 湖南省是我国主要产粮区之一。由于矿产经济活动及其他人类活动,大面积耕地土壤受到重金属污染,从而一些地方的稻米重金属含量超过国家食品卫生标准。本研究对湖南省耕地土壤与稻米重金属污染现状和成因进行剖析。结果表明:湖南耕地土壤重金属污染特征是复合污染为主,污染程度逐年上升,主要分布在湘江流域和工矿区,并逐渐蔓延至养殖区,稻米重金属污染主要以Cd为主,其次是As和Pb。针对湖南稻米重金属污染的各种防控措施,阐述其工作原理、应用实例和优缺点,然后对湖南省开展的土壤重金属污染修复措施和研究进行总结与思考,提出应当构建一种基于土壤组成的原味钝化材料耦合易操作农艺措施的经济、绿色、高效的综合性技术方案,以期来修复耕地土壤重金属污染和降低稻米重金属含量,保障粮食安全生产。 展开更多
关键词 耕地土壤 稻米 重金属 修复技术 钝化剂 湖南
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压气储能地下储气库衬砌裂缝分布特征及演化规律研究 被引量:5
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作者 蒋中明 甘露 +2 位作者 张登祥 肖喆臻 廖峻慧 《岩土工程学报》 EI CAS CSCD 北大核心 2024年第1期110-119,共10页
地下储气库衬砌的主要作用是将内压传递给围岩,且同时作为柔性密封层的附着基层。高内压作用下衬砌开裂可导致密封层出现反射型裂缝,进而引起高压气体的泄漏。为深入认识地下储气库衬砌的开裂特征,开发了基于FLAC3D平台的衬砌裂缝分析程... 地下储气库衬砌的主要作用是将内压传递给围岩,且同时作为柔性密封层的附着基层。高内压作用下衬砌开裂可导致密封层出现反射型裂缝,进而引起高压气体的泄漏。为深入认识地下储气库衬砌的开裂特征,开发了基于FLAC3D平台的衬砌裂缝分析程序,研究了衬砌配筋方式、配筋率、钢筋保护层厚度、围岩类别和温压循环荷载作用等因素对衬砌开裂演化特征的影响。研究成果表明:对衬砌采取合理的配筋方式和改善围岩质量的措施可有效控制衬砌裂缝的宽度;采用分区配筋的方式可有效控制圆形断面隧洞式储气库衬砌中的最大裂缝宽度,同时降低衬砌的配筋量。空气压力和温度同步变化引起的热力耦合效应还有助于减小衬砌中出现的裂缝宽度。 展开更多
关键词 压气储能 地下储气库 钢筋混凝土衬砌 衬砌开裂特征 裂缝宽度
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中性点柔性接地配电网故障相恢复电压暂态时域特征分析 被引量:2
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作者 喻锟 倪聪 +3 位作者 曾祥君 梁洪湘 王沾 卓超 《中国电机工程学报》 EI CSCD 北大核心 2024年第3期992-1006,I0012,共16页
配电网接地故障过零熄弧后的电压暂态恢复特性决定了系统过电压水平及电弧重燃特性,目前,中性点柔性接地配电网故障熄弧后暂态恢复电压变化机理尚不明确,为此建立柔性接地配电网接地故障暂态等值电路,理论解析故障过零熄弧后故障恢复电... 配电网接地故障过零熄弧后的电压暂态恢复特性决定了系统过电压水平及电弧重燃特性,目前,中性点柔性接地配电网故障熄弧后暂态恢复电压变化机理尚不明确,为此建立柔性接地配电网接地故障暂态等值电路,理论解析故障过零熄弧后故障恢复电压的时域表达式。在此基础上,对比分析配电网谐振接地与柔性接地方式下,系统参数变化对故障相恢复电压暂态峰值与恢复速度的影响,揭示暂态时间尺度下故障相恢复电压特征随注入零序电流值与电流注入时机的变化规律,阐明通过中性点注入可控零序电流抑制故障暂态过电压的机理。在PSCAD/EMTDC仿真环境与10 kV真型配电网实验场中模拟各种运行和故障工况,仿真与真型实验结果均验证柔性接地配电网故障相恢复电压时域解析特征与变化规律的正确性。 展开更多
关键词 配电网 柔性接地方式 故障恢复电压 暂态时域特征
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