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当前的就业形势及劳动力市场表现 预览 被引量:3
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作者 张车伟 赵文 《中国劳动》 2019年第5期5-19,共15页
我国当前劳动供给形势的根本变化主要体现为在劳动参与率下降的同时,劳动年龄人口和就业人员总量相继出现下降,这些变化意味着在需求总量不减的条件下,我国就业的主要矛盾逐步从以就业岗位不足为特征的总量矛盾转变为就业质量不高为特... 我国当前劳动供给形势的根本变化主要体现为在劳动参与率下降的同时,劳动年龄人口和就业人员总量相继出现下降,这些变化意味着在需求总量不减的条件下,我国就业的主要矛盾逐步从以就业岗位不足为特征的总量矛盾转变为就业质量不高为特征的结构性矛盾,普通劳动者工资水平和就业质量提高已成为要解决的重要问题。对此,应该降低企业负担,增强市场活力,借助新兴产业优化就业结构,让高质量经济孵化出更多高质量岗位,并做好重点群体就业工作。 展开更多
关键词 人口 就业 劳动参与率 劳动年龄人口 经济活动人口
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转向一种适应性的人口政策
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作者 任远 《南京社会科学》 CSSCI 北大核心 2019年第4期49-55,共7页
本文从生育政策的视角来讨论我国人口政策的基本理念变化和未来转型。文章首先提出了两种人口政策:一种是调节性的人口政策,一种是适应性的人口政策。作者提出我国长期以来的人口实践重视调节性的人口政策,并对调节性人口政策的逻辑基... 本文从生育政策的视角来讨论我国人口政策的基本理念变化和未来转型。文章首先提出了两种人口政策:一种是调节性的人口政策,一种是适应性的人口政策。作者提出我国长期以来的人口实践重视调节性的人口政策,并对调节性人口政策的逻辑基础进行反思。作者指出,我国在低生育率社会的背景下应该逐步转向适应性的人口政策,增强对家庭发展能力的支持,为不同人口群体和生育不同阶段提供适应性的服务,并在此基础上建设生育友好型社会。 展开更多
关键词 人口 人口政策 生育友好型社会
Ecological Optimum Population of Binzhou City Based on PEER Model 预览
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作者 Chen Shuqing 《气象与环境研究:英文版》 CAS 2019年第5期43-45,50共4页
Taking into account the regional carrying capacity,the population capacity and optimum population of Binzhou City from 2007 to 2017 under certain economic,resource and environmental conditions were calculated based on... Taking into account the regional carrying capacity,the population capacity and optimum population of Binzhou City from 2007 to 2017 under certain economic,resource and environmental conditions were calculated based on PEER model.The results show that the population capacity of Binzhou City during 2007-2017 ranged from 6.03 million to 6.43 million,and ecological optimum population was between 5.05 million and 5.34 million.The actual population of the city was between 3.74 million and 3.94 million.The impact of the "two-child" policy on population growth was small,and there was still room for population growth.The population pressure index was greater than 0.7 and less than 1,showing that economic and resource population carrying capacity had certain surplus but were still not optimistic.Environmental pressure index was relatively high,and population carrying capacity was low. 展开更多
关键词 ECOLOGICAL OPTIMUM POPULATION POPULATION capacity PEER MODEL Binzhou CITY
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砂生槐天然种群种实形态和萌发特征地理变异 预览
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作者 刘莹 麻文俊 +5 位作者 杨桂娟 王俊臣 易飞 王玉婷 王军辉 王春燕 《西北林学院学报》 CSCD 北大核心 2019年第6期22-29,36,共9页
为了更好地开展砂生槐(Sophora moorcroftiana)种质资源收集及保存工作,探究砂生槐种实性状和种子萌发性状的地理变异特征,在西藏砂生槐自然分布区挑选具有代表性的天然种群12个,测定了包括种长、种宽和种子发芽率在内的15项种实性状指... 为了更好地开展砂生槐(Sophora moorcroftiana)种质资源收集及保存工作,探究砂生槐种实性状和种子萌发性状的地理变异特征,在西藏砂生槐自然分布区挑选具有代表性的天然种群12个,测定了包括种长、种宽和种子发芽率在内的15项种实性状指标,运用巢式方差分析、相关分析及聚类分析研究了砂生槐种实、萌发性状的变异水平及其与地理因子的相关性。结果表明:1)种群间和种群内种实性状均存在显著性差异(P<0.05),种群间种子长宽积的差异最大,说明各种群的种子大小差异很大,而种群间的种长差异最大。在表型变异程度上,种群内的变异(21.91%)略大于种群间的变异(18.30%),其中种群平均表型分化系数为45.51%;这表明砂生槐的表型变异不仅仅受到遗传因素的影响,而且很大程度上受到了环境因素的调控。2)发芽率、发芽势、发芽指数和活力指数4个性状间均呈极显著正相关,发芽指数与种宽和种子长宽积呈显著相关,说明种子越饱满,发芽能力越强。3)种长、种子长宽积、荚果宽度、发芽势、发芽指数和活力指数等与海拔呈显著正相关,与经度呈显著负相关,表明砂生槐的种实大小和萌发能力从东部低海拔地区到西部高海拔地区呈上升趋势,可对高海拔优良种群加以开发利用,所有性状与纬度均无明显的相关性。4)运用ward s对砂生槐种群进行聚类分析,12个砂生槐种群大致可以划分为高海拔和低海拔2个亚群。中、高海拔亚群(3586~4207 m)的种子更饱满,千粒重更大,萌发能力更强,而中、低海拔亚群的幼苗长度、胚根长度和侧根数更高。 展开更多
关键词 砂生槐 种群 种实性状 萌发特性 种群变异
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Assessment of Urban Sprawl Using Geospatial Techniques in Awka Town, Anambra State, Nigeria 预览
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作者 Banki T. Chunwate Sani Yahaya +2 位作者 Charles O. Amankwe Ademu Samuel Benbella Ruth Madaki 《地理信息系统(英文)》 2019年第3期359-370,共12页
Cities and towns in developing countries are experiencing an unplanned and uncontrolled development known as urban sprawl. This research examines urban sprawl in Awka metropolis, between 1986 and 2016. Landsat 5 Thema... Cities and towns in developing countries are experiencing an unplanned and uncontrolled development known as urban sprawl. This research examines urban sprawl in Awka metropolis, between 1986 and 2016. Landsat 5 Thematic Mapper (TM) of 1986, Landsat Enhanced Thematic Mapper plus (ETM+) data of the year 2000 and Enhanced Thematic Mapper plus (ETM+) 2016 were used for this study. Geographic Information System was employed for the analysis of the data. Result showed that Awka metropolis witnessed a remarkable growth between 1986 and 2016 from mere 3444.48 Km2 in 1986 to about 11,452.46 Km2 in 2016. This growth contributed to the sharp decline in farmland from 25,500.51 km2 (19.13%) in 1986 to 17,848.44 km2 (13.60%) in 2000 and further declined to 10,037.07 km2 (10.01%) in 2016. Bare surfaces witnessed an increase over the years of this study. This increase is as a result of clearing of natural vegetation for urban development, thereby exposing the land to direct contact with rainfall, leading to gully erosion in the area. Light vegetation also witnessed a sharp decreased from (38.53%) in 1986 to (8.53%) in 2000. It further decreased (8.53%) to (4.62%) in 2016. Therefore, increase in population led to the increase in urban sprawl in the study area. The study recommends that there is a need for a regular monitoring of urban sprawl and development in the study area by the state government especially with the aid of geospatial techniques for better decision making. 展开更多
关键词 URBAN SPRAWL Landuse/Cover POPULATION Change Development GIS
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新中国成立70年来的城镇化建设及其未来应然走向 预览
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作者 许伟 《武汉大学学报:哲学社会科学版》 CSSCI 北大核心 2019年第4期13-20,共8页
新中国成立70年来的城镇化建设大体上历经了苏联式社会主义城镇化建设、中国特色城镇化建设、中国特色新型城镇化建设三个阶段,表现出土地和人口双要素驱动、中央政府和市场及地方政府三方推进、城镇规模多样化发展、城镇化资源供给的... 新中国成立70年来的城镇化建设大体上历经了苏联式社会主义城镇化建设、中国特色城镇化建设、中国特色新型城镇化建设三个阶段,表现出土地和人口双要素驱动、中央政府和市场及地方政府三方推进、城镇规模多样化发展、城镇化资源供给的国内国际两重支撑等鲜明的中国特点,其未来的应然走向是:第一,城镇化建设的土地和人口要素驱动需要向创新和绿色驱动转变;第二,在中央政府、市场和地方政府三方推进城镇化建设的情况下,要注重防范权力扩张和资本扩张对人民利益的侵犯;第三,在城镇规模多样化发展的同时,要注重多种规模城市的协调化、体系化发展;第四,在城镇化资源供给的国内国际两重支撑方面,要更加重视整合国际资源开发国内市场。 展开更多
关键词 新中国成立70年 城镇化 中国特色新型城镇化 政府 市场 土地 人口
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Multiple factors correlating with wing malformations in the population of Parnassius apollo (Lepidoptera: Papilionidae) restituted from a low number of individuals: A mini review
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作者 Karolina Pierzynowska Marta Skowron Volponi Grzegorz Wegrzyn 《昆虫科学:英文版》 SCIE CAS CSCD 2019年第3期380-387,共8页
The Apollo butterfly, Parnassius apollo (Linnaeus), was common in Europe over 100 years ago, but currently it is considered as near threatened. Different conservation programs have promoted the persistence of this spe... The Apollo butterfly, Parnassius apollo (Linnaeus), was common in Europe over 100 years ago, but currently it is considered as near threatened. Different conservation programs have promoted the persistence of this species;however, it is still endangered. An example of such programs was the action devoted to reestablish the Apollo butterfly population in Pieniny National Park (Poland) from only 20-30 individuals which had survived till the last decade of the 20th century. This reintroduction has been successful;however, unexpected developmental problems appeared. Butterflies with deformed or reduced wings became frequent in the population living in the natural habitat, and particularly among those reared under seminatural conditions (in the same environment, but fenced by a net). Until recently, reasons for these malformations remained unknown. However, reports published during last months indicated that there are genetic, biochemical, and microbiological factors contributing to this phenomenon. In the malformed individuals, lesions in the wingless gene and dysfunctions of laccase 1 and 2 were found to be significantly more frequent than in normal insects. A large fraction of butterflies with deformed or reduced wings was devoid of the prokaryotic symbiont Wolbachia, which was present in most normal individuals. Moreover, Yersinia pseudotuberculosis (Pfeiffer) Smith and Thai, and Serratia sp., bacteria pathogenic to insects, were detected in the biological material from both normal and malformed butterflies from this population. These findings are summarized and discussed in this review, in the light of conservation of insects and restitution of their populations from a low number of individuals. 展开更多
关键词 Apollo butterfly LACCASES malformed wings POPULATION RECONSTITUTION WINGLESS gene Wolbachia
西藏土地资源承载力的现实与未来--基于膳食营养当量分析
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作者 郝庆 封志明 +1 位作者 杨艳昭 朱鹤 《自然资源学报》 CSSCI CSCD 北大核心 2019年第5期911-920,共10页
土地承载力是人地关系的基础表征,开展土地承载力评价可以为实施农业空间治理、制定农业发展政策等提供参考。以西藏自治区为例,基于人体每日所需热量、蛋白质和脂肪评价土地的现实承载力及其变化。评价结果表明:(1)西藏自治区土地承载... 土地承载力是人地关系的基础表征,开展土地承载力评价可以为实施农业空间治理、制定农业发展政策等提供参考。以西藏自治区为例,基于人体每日所需热量、蛋白质和脂肪评价土地的现实承载力及其变化。评价结果表明:(1)西藏自治区土地承载指数从2004-2016年一直维持在80.66%~89.84%之间,处于平衡有余状态。(2)未来西藏自治区土地承载指数将会持续保持在87.5%之上,呈现先升后降的变化态势,在2032年达到峰值,届时土地承载指数将会超过92.56%;此后将会持续下降,在2050年将低于90%。以土地承载力评价为基础,根据未来食物消费需求变化和西藏自治区的自然条件,提出不增加农牧业开发强度,保持农牧业生产空间规模稳定,并逐步优化调整农牧业发展结构,适度降低粮食种植面积,在适宜地区扩大蔬菜、瓜果种植,以及发展草牧业经济等建议。 展开更多
关键词 承载力 空间治理 人口 膳食营养 西藏
Analytic solutions for generalized PT-symmetric Rabi models
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作者 董元浩 张文静 +1 位作者 刘静 谢小涛 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第11期161-167,共7页
We theoretically investigate the exact solutions for generalized parity–time(PT)-reversal-symmetric Rabi models driven by external fields with monochromatic periodic, linear, and parabolic forms, respectively. The co... We theoretically investigate the exact solutions for generalized parity–time(PT)-reversal-symmetric Rabi models driven by external fields with monochromatic periodic, linear, and parabolic forms, respectively. The corresponding exact solutions are presented in terms of the confluent Heun equations without any approximation. In principle, the analytic solutions derived here are valid in the whole parameter space. Such a kind of study may offer potential coherent control schemes of the PT-symmetric two-level systems. 展开更多
关键词 RABI model PT SYMMETRY POPULATION dynamics
东方水韭种群分布格局研究
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作者 胡蔚 黄均华 +4 位作者 吕超鹏 邵建均 胡惠珍 葛佳颖 胡绍庆 《浙江理工大学学报》 2019年第3期367-373,共7页
以浙江省松阳县的安民乡安岱后村小烂湖和叔婆湾为样地,对濒危珍稀物种东方水韭的种群空间分布格局进行研究,探讨其分布规律、形成原因、种群保护及更新策略。结果显示:松阳县的东方水韭种群的分布格局以聚集分布为主,且叔婆湾种群聚集... 以浙江省松阳县的安民乡安岱后村小烂湖和叔婆湾为样地,对濒危珍稀物种东方水韭的种群空间分布格局进行研究,探讨其分布规律、形成原因、种群保护及更新策略。结果显示:松阳县的东方水韭种群的分布格局以聚集分布为主,且叔婆湾种群聚集强度明显高于小烂湖种群。东方水韭种群聚集分布的原因在于东方水韭本身的生物和生态学特性,且与其种群分布的小生境水域流动性有关,即水域流动越慢种群聚集强度越大。做好生境保护,加强人工繁殖扩大种群规模有利于保护和更新东方水韭的种群。 展开更多
关键词 东方水韭 种群 分布格局 群落结构 聚集强度
不同产地忽地笑的叶绿体基因psbA-trn H序列分析
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作者 全妙华 赵丽娟 +3 位作者 贺安娜 佘朝文 向小亮 蒋向辉 《中草药》 CAS CSCD 北大核心 2019年第2期491-501,共11页
目的通过叶绿体基因psbA-trn H序列分析,探讨我国忽地笑种质资源的系统进化关系及分子鉴定方法。方法分别提取15省(市)52个忽地笑居群的DNA,经PCR扩增叶绿体基因psbA-trn H序列及测序,并用Mega5.0等软件对测序结果进行分析。结果 52条ps... 目的通过叶绿体基因psbA-trn H序列分析,探讨我国忽地笑种质资源的系统进化关系及分子鉴定方法。方法分别提取15省(市)52个忽地笑居群的DNA,经PCR扩增叶绿体基因psbA-trn H序列及测序,并用Mega5.0等软件对测序结果进行分析。结果 52条psbA-trn H序列长度为544~656 bp,GC含量为35.8%~37.0%,遗传距离为0.000 00~0.009 47;核苷酸变异(多态性)位点数共33个,其中简约信息位点9个,单一突变位点18个,插入/缺失片段6个;单倍型数量(H)10个,单倍型多态性水平(Hd)0.749,核苷酸多态性(π)0.002 63,收集的忽地笑资源具有较高的遗传多样性。最大简约法(maximum parsimony,MP)系统树中52个居群聚为4类,并且该聚类结果与其地理分布基本一致。结论不同产地忽地笑居群的遗传变异较大,psb A-trn H序列可作为忽地笑种源分子鉴定的依据;我国忽地笑种质资源在进化上具有明显的地域性特征。 展开更多
关键词 忽地笑 居群 psbA-trnH序列 核苷酸多态性 系统聚类
Spatio-temporal evolution of ecologically-sustainable land use in China’s Loess Plateau and detection of its influencing factors
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作者 QU Lu-lu LIU Yan-sui CHEN Zong-feng 《山地科学学报:英文版》 SCIE CSCD 2019年第5期1065-1074,共10页
Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to surv... Ecological land(Eco-land) is a basic resource for human beings to survive, and eco-land use is a strategy, a way to manage the land resource. So, ecologically-sustainable land use is essential for human beings to survive. This paper investigates the spatiotemporal characteristics and mechanisms of urban-rural eco-land using a new and innovative integration way based on eco-land change data in China’s Loess Plateau(LP) prefecture level cities and explores factors of eco-land change. The spatial difference characteristic of eco-land among different level cities in the LP is that: small cities > big cities > middle cities. From 2009 to 2016, the eco-land in the LP from the perspective of urban-rural areas has changed significantly. Significant differences of urban-rural eco-land were identified among various urban growth types, and all the cities in the LP were further classified into four types based on eco-land change trend, with type A and B cities identified as the vital zone and major zone. Taking the eco-fragile region Loess Plateau(LP) as an example, our results demonstrated that the migrants to cities in LP could relieve ecological pressures and promote restoration of ecological vegetation. We have demonstrated that urbanization and the influence of government policy can be discerned through the quantification of the spatial-temporal change of eco-land and suggest that combining both urban and rural eco-land can support more effective land use decisions and provide theoretical basis for the practical application of urban planning, policy-making and sustainable development. What’s more, governments should strive to population mobility and restore vegetation to sustain this fragile ecological environment. 展开更多
关键词 Ecologically-sustainable land use SPATIO-TEMPORAL EVOLUTION influencing factor Population migration LOESS PLATEAU
Road traffic safety:An analysis of the cross-effects of economic,road and population factors
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作者 Li-Lu Sun Dan Liu +1 位作者 Tian Chen Meng-Ting He 《中华创伤杂志:英文版》 CAS CSCD 2019年第5期290-295,共6页
Purpose:Through the study of economic,traffic and population data related to road traffic accidents from 2004 to 2016,this paper analyzed the impact of various factors on road traffic casualties in China,and provided ... Purpose:Through the study of economic,traffic and population data related to road traffic accidents from 2004 to 2016,this paper analyzed the impact of various factors on road traffic casualties in China,and provided theoretical basis and suggestions for the road traffic safety management in China.Methods:Based on three aspects(economy,road,population)with five factors(gross domestic product(GDP),traffic in vestme nt,new vehicle own ership,new road mileage and newly in creased population),this paper collected the re leva nt data of road traffic accidents in 31 provinces and cities in China,from 2004 to 2016.A panel model was established to carry out empirical analysis.Results:All factors have a significant impact on the number of road traffic accident casualties.When other factors remain unchanged,the number of road traffic casualties decreased by an average of 0.19 for every 100 million CNY increased in GDP.For every 100 million CNY increased in traffic investment,the number of road traffic casualties is reduced by an average of 13.93,indicating that economic development can improve road traffic safety to a certain extent.On the contrary,the growth in road mileage,new motor vehicles and population has increased the number of road traffic casualties.For every 10,000 km of new road mileage,the number of traffic accident casualties has increased by 284.04.For every 10,000 newboms,the number of road traffic casualties increased by 7.33;as the number of new motor vehicles increases by 10,000,the number of road traffic casualties increased by an average of 21.77.Conclusion:The increase of GDP and traffic investment can significantly reduce the number of road traffic casualties in China,which shows that economic development is essential to improve road traffic safety.The numbers of new road mileage,newly increased population and the new motor vehicles are positively correlated with the number of traffic accident casualties in traffic accidents,which reflects the existing problems in road design,distribution of road res 展开更多
关键词 ROAD traffic safety Panel data Economic road and POPULATION FACTORS WOUNDS and INJURIES
基于多源数据的福建省人口数据空间化研究 预览
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作者 杨晓荣 陈楠 《贵州大学学报:自然科学版》 2019年第2期79-84,95共7页
针对人口统计数据无法精细直观反映人口真实的空间分布状况的问题,该文以福建省为例,对其2015年的人口数据进行空间化。以多源数据为基础数据,在县级尺度上采用了空间回归模型构建福建省2015年福建省500m人口空间分布数据,在乡镇尺度上... 针对人口统计数据无法精细直观反映人口真实的空间分布状况的问题,该文以福建省为例,对其2015年的人口数据进行空间化。以多源数据为基础数据,在县级尺度上采用了空间回归模型构建福建省2015年福建省500m人口空间分布数据,在乡镇尺度上对其空间化结果进行精度验证并与WorldPop、中国公里网格人口分布数据集比较。结果表明:NPP/VIIRS夜间灯光、路网、DEM、土地利用数据与人口具有较强的相关性,有足够能力模拟人口的空间分布;对于2015年福建省人口数据空间化,空间误差模型比空间滞后模型的回归拟合效果更好;人口数据空间化结果精度比较高,在空间上能精细展现2015年福建省的人口分布状况;人口高值区主要集中在县城所在地,人口呈现出主城区高、四周低的空间分布格局。 展开更多
关键词 人口 影响因素 空间回归 空间化
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温度、光照及PEG胁迫对不同生态型醉马草种子萌发的影响 预览
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作者 刘雪松 《草业科学》 CAS CSCD 2019年第6期1600-1607,共8页
为研究醉马草(Achnatherum inebrians)种群繁殖和环境适应机理,本研究从甘肃榆中(YZ)和内蒙古阿拉善(Alxa)采集的两个醉马草种群的种子作为试验材料,研究不同温度(10℃/20℃、15℃/25℃和20℃/30℃变温12h/12h)、光照(完全光照和完全黑... 为研究醉马草(Achnatherum inebrians)种群繁殖和环境适应机理,本研究从甘肃榆中(YZ)和内蒙古阿拉善(Alxa)采集的两个醉马草种群的种子作为试验材料,研究不同温度(10℃/20℃、15℃/25℃和20℃/30℃变温12h/12h)、光照(完全光照和完全黑暗)以及PEG浓度(0、-0.3、-0.6和-0.9MPa)共同作用对两种醉马草种子发芽率、发芽指数、胚根和胚芽长的影响。结果表明,在一定的渗透胁迫范围内(-0.6和-0.9Mpa),温度对醉马草种子萌发有显著影响,15℃/25℃条件下,各水分处理的两种醉马草的发芽率、发芽指数、胚根长和胚芽长均达到最大值,该温度为醉马草的最适萌发温度;光照对两种醉马草种子的发芽率和发芽指数没有显著影响;在同一温度条件下,两种醉马草的发芽率、发芽指数、胚芽长均随着PEG浓度的升高而减小,且均与无菌水对照差异显著(P<0.05);与YZ醉马草种子相比,Alxa醉马草种子萌发的速度和整齐度较好,种子的活力较强。因此,无论是在光照、温度或水分胁迫条件下,Alxa醉马草与YZ醉马草相比更具有较强的抗逆性和适应性,可作为醉马草繁殖扩散和开发利用的优良草种。 展开更多
关键词 醉马草 种群 发芽率 发芽指数 幼苗生长 温度 光照
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人口-经济-生态环境耦合协调发展研究 预览 被引量:1
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作者 舒婷 雷思友 《中国环境管理干部学院学报》 CAS 2019年第3期60-63,共4页
综合考虑人口、经济、生态环境三方面因素,构建两淮地区耦合协调评价指标体系。采用熵权法对两淮地区2007—2017年的28个评价指标进行赋权,利用耦合协调度模型对原始数据进行量化分析。研究表明,两淮地区2007—2017年间的耦合协调度呈... 综合考虑人口、经济、生态环境三方面因素,构建两淮地区耦合协调评价指标体系。采用熵权法对两淮地区2007—2017年的28个评价指标进行赋权,利用耦合协调度模型对原始数据进行量化分析。研究表明,两淮地区2007—2017年间的耦合协调度呈不明显的上升趋势,耦合协调发展类型为极度失调衰退型与严重失调衰退型。针对两淮地区耦合协调发展现状,结合其特殊的经济发展模式,提出针对性的建议与对策。 展开更多
关键词 人口 经济 生态环境 耦合协调度
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英国国家公园法律制度及其对我国国家公园立法的启示 预览
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作者 李爱年 肖和龙 《时代法学》 2019年第4期27-33,共7页
中英两国国家公园区域人口密集度都比较高,都面临现实的自然保护与经济社会发展困境。英国从1951年第一个国家公园设立至今已有近70年的历史,已经建立了较为成熟的国家公园体制。英国国家公园采用综合型的管理体系,形成了以政府为主导,... 中英两国国家公园区域人口密集度都比较高,都面临现实的自然保护与经济社会发展困境。英国从1951年第一个国家公园设立至今已有近70年的历史,已经建立了较为成熟的国家公园体制。英国国家公园采用综合型的管理体系,形成了以政府为主导,非政府共同参与的多元共治模式;设立保护优先的管理目标,在保护的前提下发展;在多层次的规划管理下,保证了英国国家公园规划制度的权威性和严肃性;在规划前提下,严格控制公园内人口增长。我国目前处于建设国家公园的初期,在立法体系、管理制度、规划管理等方面可以借鉴英国相关成熟经验,对我国尽快建立成熟的国家公园体制有重要的意义。 展开更多
关键词 国家公园 立法 自然保护地 管理体制 规划
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Association between PPARG genetic polymorphisms and ischemic stroke risk in a northern Chinese Han population: a case-control study 预览
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作者 Yan-Zhe Wang He-Yu Zhang +3 位作者 Fang Liu Lei Li Shu-Min Deng Zhi-Yi He 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第11期1986-1993,共8页
Two common polymorphisms of the peroxisome proliferator-activated receptor gamma(PPARG) gene, rs1801282 and rs3856806, may be important candidate gene loci affecting the susceptibility to ischemic stroke. This case-co... Two common polymorphisms of the peroxisome proliferator-activated receptor gamma(PPARG) gene, rs1801282 and rs3856806, may be important candidate gene loci affecting the susceptibility to ischemic stroke. This case-control study sought to identify the relationship between these two single-nucleotide polymorphisms and ischemic stroke risk in a northern Chinese Han population. A total of 910 ischemic stroke participants were recruited from the First Hospital of China Medical University, Shenyang, China as a case group, of whom 895 completed the study. The 883 healthy controls were recruited from the Health Check Center of the First Hospital of China Medical University, Shenyang, China. All participants or family members provided informed consent. The study protocol was approved by the Ethics Committee of the First Hospital of China Medical University, China on February 20, 2012(approval No. 2012-38-1). The protocol was registered with the Chinese Clinical Trial Registry(registration number: ChiCTR-COC-17013559). Plasma genomic DNA was extracted from all participants and analyzed for rs1801282 and rs3856806 single nucleotide polymorphisms using a SNaPshot Multiplex sequencing assay. Odds ratios(ORs) and 95% confidence intervals(CIs) were calculated using unconditional logistic regression to estimate the association between ischemic stroke and a particular genotype. Results demonstrated that the G allele frequency of the PPARG gene rs1801282 locus was significantly higher in the case group than in the control group(P < 0.001). Individuals carrying the G allele had a 1.844 fold increased risk of ischemic stroke(OR = 1.844, 95% CI: 1.286–2.645, P < 0.001). Individuals carrying the rs3856806 T allele had a 1.366 fold increased risk of ischemic stroke(OR = 1.366, 95% CI: 1.077–1.733, P = 0.010). The distribution frequencies of the PPARG gene haplotypes rs1801282-rs3856806 in the control and case groups were determined. The frequency of distribution in the G-T haplotype case group was significantly higher than that in 展开更多
关键词 nerve REGENERATION STROKE cerebral ischemia ISCHEMIC STROKE PEROXISOME proliferator-activated receptor γ single-nucleotide polymorphism haplotype analysis interaction CASE-CONTROL study Chinese Han population neural REGENERATION
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基于区域划分方法的中国人口分布格局及变化研究——从1953年到2010年
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作者 刘翠玲 许亚平 王法辉 《地理学报:英文版》 SCIE CSCD 2019年第11期1908-1922,共15页
This study uses six censuses (1953,1964,1982,1990,2000,and 2010) at the county level since the foundation of the People’s Republic of China to examine the changes of population density pattern in mainland China over ... This study uses six censuses (1953,1964,1982,1990,2000,and 2010) at the county level since the foundation of the People’s Republic of China to examine the changes of population density pattern in mainland China over time.Based on the Gini coefficient,the change of disparity in population density followed a “U-shaped” trend,i.e.,decreasing during 1953–1982 and increasing during 1982–2010.The shrinking disparity in the pre-reform periods was largely attributable to various ill-conceived political movements,and the enlarging gap in population growth rates in the post-reform era reflected a natural outcome of urbanization,which will continue in the foreseeable future.In addition,this research employs a GIS-automated regionalization method,REDCAP,to uncover a natural demarcation line like the classic “Hu Line” that divides China into two regions of similar area sizes but a strong contrast in population.The results show that the regionalization-derived lines were largely consistent with the Hu Line over time.Therefore,the disparity between the high-density southeast and low-density northwest regions is likely due to differing physical environments that form a natural barrier.Any public policy to overcome this barrier at a large scale is destined to be a vain attempt. 展开更多
关键词 regional population distribution TEMPORAL change DISPARITY GINI COEFFICIENT REGIONALIZATION GIS HU Line China
Coordinated Development of Population, Economy and Environment System and Diagnosis of Its Obstacle Factors in Nanjing 预览
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作者 Liu Binglin Jiang Shengnan +3 位作者 Xu Minghui Xing Yun Wu Haotian Li Lu 《气象与环境研究:英文版》 CAS 2019年第5期38-42,共5页
Promoting the coordinated development of regional population,economy and environment is beneficial to the realization of sustainable development.Based on the construction of evaluation index system of coordinated deve... Promoting the coordinated development of regional population,economy and environment is beneficial to the realization of sustainable development.Based on the construction of evaluation index system of coordinated development of systems,the entropy weight-TOPSIS method and coupling coordination model,the coordinated development degree of population,economy and environment system in Nanjing was measured,and the temporal variation characteristics of each subsystem and their coordinated development degree form 1997 to 2016 were analyzed.The results showed that the development of population,economy system and environment system in Nanjing was generally in a continuous upward trend.Among them,the economy system developed fastest.The coordinated development degree of population,economy system and environment system in Nanjing was constantly increasing but still at a low level;the degree was only in the primary coordination phase,and its type was environment lagging.The economy subsystem and environment subsystem were important factors restricting the development of population,economy and environment in Nanjing,and the main obstacle factor was the production of industrial solid waste.The results above can provide a scientific basis for promoting the coordinated development of population,economy and environment system in Nanjing and achieving regional sustainable development. 展开更多
关键词 Population economy and environment system COORDINATED development degree of systems ENTROPY weight-TOPSIS OBSTACLE factors NANJING
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