112 research outputs found

    Neighboring / Adjacent Coupling Relationship Between Urbanization and Farmland Safety Based on the Decoupling Theory

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    当前我国快速城市化推进对半城市化、农村等近程区域分布的耕地产生直接、强烈的影响,也对耕地安全造成强大的胁迫效应。为此,构建城市化-耕地安全综合评; 价指标体系,分别计算城市化指数和耕地安全胁迫指数,并基于脱钩理论方法对城市化水平与耕地安全水平的近程耦合关系进行量化分析。以江苏省连云港市为例,; 定量分析20002014年间其城市化水平与耕地安全的脱钩-耦合关系及耕地安全对城市化进程的响应程度。结果表明,; 20002014年间,连云港市城市化指数持续增高,耕地安全胁迫指数波动降低;; 20002007年为强脱钩、弱脱钩、扩张负脱钩及扩张脱钩的波动状态;; 20082014年呈更加强烈的波动状态,包括20082012年的强脱钩和2013年的扩张负脱钩状态,这反映出区域发展规划、土地利用规划和城市总体; 规划的实施对这一典型近程耦合系统产生了较大影响。研究期内连云港市城市化水平大幅提高,耕地安全所受胁迫程度不断降低,两者虽总体呈强脱钩关系,但仍需; 注意近程耦合结果波动性较大所揭示的不确定性问题,需要谨慎权衡城市化相关政策对耕地安全的影响。与过去的宏观、单一指标模型相比,基于近程耦合关系提出; 的多指标脱钩-耦合模型更具综合性,能更加全面、精细化分析快速城市化进程与耕地安全保护之间的复杂关系,为半城市化地区景观安全格局评估提供支撑,为城; 市化与耕地保护之间的协调发展提供决策支持。The current rapid development of urbanization in China has directly and; seriously affected farmlands distribution in its para-urbanized; neighboring /adjacent regions,and also posed severe stresses on safety; of these land. It is,therefore,essential to build up a comprehensive; urbanization and farmland safety assessment indicator system,work out; quantitatively urbanization index and farmland safety stress index,and; analyze quantitatively neighboring coupling relations between; urbanization and arable land safety based on the decoupling theory and; method. A case study was conducted of Lianyungang City of Jiangsu; Province to explore quantitatively coupling-decoupling relationship; between urbanization and farmland safety and response of farmland safety; to the progress of urbanization during the period from 2000 to 2014.; Results show that during the study period,urbanization index of; Lianyungang City increased steadily,while farmland safety stress index; fluctuated with a declining trend. Their relationship displayed a wavy; trend from 2000 to 2007,i.e. strong decoupling-weak decoupling-expanding; negative decoupling-expanding connection and a strong fluctuation curve; from 2008 to 2014,including strong decoupling during 2008-2012 and; expanding negative decoupling in 2013,which reflects strong impacts of; the implementation of the regional development,land use and city overall; programs on this typical neighboring / adjacent coupling system. During; the study period,Lianyungang City made a huge and steady progress in; urbanization, while reducing fluctuation of its stress on farmland; safety. Though the two posed a strong decoupling relationship,the; problem of uncertainty reflected in the huge fluctuation of the result; of the neighboring /adjacent decoupling calls for high attention,and the; influence urbanization had on farmland safety needs to be weighed; prudently. Compared to the macroscopic single indicator models used in; the past,the multi-index decoupling-coupling model built for the; neighboring coupling relationship is more comprehensive and capable of; analyzing the complex relationship between rapid urbanization and; protection of farmland safety in a more holistic and finer way.; Furthermore,it may provide theoretical support to landscape safety; assessment of para-urbanizd regions and to decision-making on harmonized; development of both urbanization and protection of farmland.国家自然科学基金; 厦门大学大学生创新创业训练计划; 中国科学院大学生创新实践训练计

    H5N1禽流感病毒血凝素抗原快速检测试剂对不同现场标本的检测比较

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    利用H5亚型禽流感病毒血凝素抗原快速检测试剂“H5-HA(Ag)Dot-ELISA(H5-Dot)”对来自陆禽、水禽的484份气管拭子、泄殖腔拭子和粪便拭子标本进行检测,结果:①不同采集方式的H5N1阳性标本的检出率高低有别,气管拭子的检出率最高,泄殖腔拭子次之,粪便拭子最低(P<0·05),因此建议现场采样时应尽可能采集气管拭子标本;②陆禽标本检出率显著高于水禽标本(P<0·05),对病毒培养阳性的陆禽气管拭子检出率达80%(95%CI:70·6%~87·8%),对水禽气管拭子标本的检出率为38%(95%CI:26·9%~49·4%),可能与标本中病毒滴度高低有关;③有症状与无症状陆禽标本的检出率无显著差异。另外,H5-Dot试剂对333份非H5病毒气管拭子标本的特异性为99·4%(95%CI:97·9%~99·9%)。这些结果表明,H5-Dot是一种较为可靠的H5亚型禽流感病毒早期快速检测方法,在缺乏仪器设施和高素质专业技术人员的H5N1禽流感病毒防控第一线具有重要推广价值

    一种新型H5N1禽流感病毒血凝素抗原快速检测试剂的建立

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    利用5株广谱特异性抗H5亚型血凝素单克隆抗体和酶联免疫渗滤技术成功地建立了一种适于现场检测H5亚型禽流感病毒血凝素蛋白的抗原快速检测试剂H5-HA(Ag)Dot-ELISA。该试剂对41株代表当前亚洲地区流行的各种遗传变异亚系H5N1禽流感病毒检测均为阳性,对多数毒株的分析灵敏度优于0.1个血凝滴度(HA titer),其中部分优于0.01个血凝滴度;比较该试剂与早期开发的同类ELISA试剂,发现前者对后者未能检出的H5N1新变异株检测均为阳性;利用该试剂和商品化Directigen Flu A(BD)试剂检测两株H5N1病毒株,提示前者灵敏度高于后者;该试剂对一株H5N1病毒的检测灵敏度与标准RT-PCR相当;该试剂对24株非H5亚型病毒检测均为阴性,显示出良好特异性。以上结果提示,此研究建立的H5N1病毒抗原快速检测试剂在H5禽流感现场检测上具有较好的应用前景

    低龄DDH患儿初次开放复位术中股骨截骨必要性的前瞻性随机对照试验研究方案

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    回顾性研究发现,股骨截骨术并非低龄DDH患儿手术治疗所必须的,而应根据患儿具体情况合理选择;本研究通过多中心前瞻性研究进一步探讨对于18个月至3岁DDH患儿是否要行股骨截骨术。FSODDH项目为一项多中心前瞻性随机对照临床试验研究。研究设计拟招募200名单侧低龄DDH患儿,随机分成股骨截骨组(n=100)和股骨不截骨组(n=100)。股骨截骨组患儿全部采取髋关节开放复位术、骨盆截骨术及股骨截骨术治疗;股骨不截骨组患儿全部采取髋关节开放复位术及骨盆截骨术治疗;术后定期随访至少2年。收集术前、术后1周、术后1个月、术后3个月、术后6个月、术后1年及术后2年的髋关节正位X线影像资料,比较两组患儿的髋臼指数、股骨头坏死率、再脱位率、术中出血量、手术时间和住院天数等临床指标。这一多中心前瞻性研究将能为低龄DDH患儿是否需行股骨截骨术提供循证医学证据

    1978~2008年中国湿地类型变化

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    分别基于美国陆地卫星(Landsat MSS/TM/ETM+)和中巴资源卫星(CBERS-02B)影像数据,以人工目视解译为主,完成了中国1978~2008年4期(基准年分别为1978,1990,2000和2008年)湿地遥感制图,并进行了大量的室内外验证.在此基础上,对我国湿地现状及近30年来湿地变化进行了初步分析,得到以下主要结论:(ⅰ)截止2008年,中国湿地面积约为324097km2,其中以内陆沼泽(35%)和湖泊湿地(26%)为主.(ⅱ)1978~2008年,中国湿地面积减少了约33%,而人工湿地增加了约122%.过去30年里湿地减少的速度大幅降低,由最初5523km2/a(1978~1990年)降为831km2/a(2000~2008年).(ⅲ)减少的自然湿地(包括滨海湿地和内陆湿地),其类型变化由湿地向非湿地转化的比例逐渐降低.初期(1978~1990年)几乎全部(98%)转换为非湿地;在1990~2000年间减少的自然湿地约有86%转化为非湿地,而在2000~2008年,这一比例下降为77%.(ⅳ)气候变化和农业活动是中国湿地变化的主要驱动因素,湿地变化在中国分为三大不同特征区域,即西部三省/自治区(西藏、新疆和青海)、北部两省/自治区(黑龙江和内蒙古)和其他省市区.其中西部区域尤其是青藏高原,湿地变化的驱动因子以气候增温为主;新疆湿地由于气候增温和农业活动共同作用造成变化不大.北部省/自治区的湿地变化则主要由农业活动引起;而其他省市区的湿地变化几乎完全受控于人类的农业经济活动

    The Research of the Tang Princesses' Family Life

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    郭海文,陕西师范大学历史文化学院副教授,主要致力于中国古代史、性别史研究。【中文摘要】过去的历史研究,太过忽略女性,以至建构出来的历史图像有很大的缺陷。在传统中国,家庭是绝大多数妇女唯一可能有深度参与的生活领域,对了解过往的女性而言,家庭史的研究具有重要性。本文对大唐公主的家庭生活从公主与娘家血肉相连的关系、公主在夫家的人际网络——以与舅姑关系为中心、公主驸马的相处之道、为人母之道——生育与母子亲情等方面加以系统阐释,以期勾勒出公主的家庭生活场景及生存空间。 【Abstract】During the past time, we have always ignored women in historical research, which has resulted in there were a lot of deficiencies in the construction of historical images. In traditional China, family might be the only place where the great majority of women have taken part in deeply. Studying family history makes a big influence on learning about women. This paper hackles Tang princesses' family life, which is divided into four parts. First, introduce the relationship between a princess and her family. Second, the relationship between the princess and her parents-in-law locates in the center of the princess's interpersonal network in her husband's family. Third, how the princess went along with her husband. Fourth, giving birth to her children and the affection between the princess and their children is the princess's maternity. By analyzing the four aspects of Tang princesses’ family life,we can outline the princess’s family life scenes and living space.本文为2015年国家社科基金后期资助项目“大唐公主命运图谱”(15FZS037)阶段性成果
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