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中国农垦农业全要素生产率变化及其区域差异分析 预览
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作者 廖文康 王介勇 李红梅 《中国农业资源与区划》 CSSCI CSCD 北大核心 2019年第5期71-77,共7页
[目的]农垦已经成为我国国有农业经济的骨干和引领农业现代化发展的重要力量。分析我国农垦农业全要素生产率变化态势、区域差异及主要限制因素,提出提升农垦农业全要素生产率对策建议。[方法]采用DEA-Malmquist全要素生产率指数法,利... [目的]农垦已经成为我国国有农业经济的骨干和引领农业现代化发展的重要力量。分析我国农垦农业全要素生产率变化态势、区域差异及主要限制因素,提出提升农垦农业全要素生产率对策建议。[方法]采用DEA-Malmquist全要素生产率指数法,利用全国30个垦区投入产出数据,评价分析2004—2015年农垦农业全要素生产率变化及其区域差异。[结果]2004—2015年农垦农业全要素生产率总体上呈增长趋势,其平均值为1.104,技术进步变化平均值为1.160,技术效率变化平均值为0.953;农垦农业全要素生产率增长相对较快的区域为东北地区、黄淮海平原地区、东南沿海和新疆地区,增长相对较慢的区域为黄土高原地区、西南喀斯特地区和东南山地丘陵区等。[结论]2004—2015年农垦农业全要素生产率持续提升,技术进步是全要素生产率增加的主要驱动因素,而技术效率是其主要抑制因素,农垦农业发展主要依赖农业技术进步,而农业经营管理方式仍然相对较粗放;农垦农业全要素生产率变化呈现显著的区域差异特征,根据农业全要素生产率变化特征将全国垦区划分为高全要素生产率—规模效率驱动型、高全要素生产率技术驱-动型、低全要素生产率—规模效率驱动型和低全要素生产率—技术驱动型4种类型。建议通过完善农垦土地利用与管理制度、建立农垦现代企业用人制度和新型垦农关系、因地制宜分类分区推进农垦农业经营管理改革与创新,全面提升农垦农业全要素生产率。 展开更多
关键词 农垦 农业全要素生产率 DEA-Malmquist生产指数法 变化 区域差异分析
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Science opportunities and challenges associated with SKA big data
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作者 Tao An 《中国科学:物理学、力学、天文学英文版》 SCIE EI CAS CSCD 2019年第8期121-126,共6页
The upcoming Square Kilometre Array (SKA) radio telescope will become the largest astronomical observation facility,and is expected to introduce revolutionary changes in major fields of natural sciences.These revoluti... The upcoming Square Kilometre Array (SKA) radio telescope will become the largest astronomical observation facility,and is expected to introduce revolutionary changes in major fields of natural sciences.These revolutionary changes help us to answer the fundamental questions related to the origins of the universe,life,cosmic magnetic field,the nature of gravity,and to search for extraterrestrial civilizations [1]. 展开更多
关键词 SQUARE Kilometre Array(SKA) INTRODUCE REVOLUTIONARY changes FUNDAMENTAL QUESTIONS related
Technology Changes Childhood
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《中国妇女:英文月刊》 2019年第7期7-9,共3页
American psychologist Alison Gopnik had an article, Is "Screen Time" Dangerous for Children?, published on Newyorker.com in 2016. Many parents worry that "screen time" will impair their children... American psychologist Alison Gopnik had an article, Is "Screen Time" Dangerous for Children?, published on Newyorker.com in 2016. Many parents worry that "screen time" will impair their children's development. Gopnik said such fears were overblown. She said she believed content and context-what children watch and with whom they watch it-mattered the most. 展开更多
关键词 TECHNOLOGY CHANGES CHILDHOOD AMERICAN PSYCHOLOGIST Alison Gopnik
我国城市轨道交通发展的政策变迁 预览
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作者 杨永平 赵东 边颜东 《都市快轨交通》 北大核心 2019年第1期4-8,共5页
在国家有关文件要求和政策指导下,我国城市轨道交通一直规范有序发展。在当前严控地方债务、防范系统性金融风险的大环境下,城市轨道交通进入新的发展阶段,国办发〔2018〕52号文将在今后一段时期指导和规范我国城市轨道交通健康有序发... 在国家有关文件要求和政策指导下,我国城市轨道交通一直规范有序发展。在当前严控地方债务、防范系统性金融风险的大环境下,城市轨道交通进入新的发展阶段,国办发〔2018〕52号文将在今后一段时期指导和规范我国城市轨道交通健康有序发展。按照缓慢发展、加快发展和快速发展3个阶段,总结梳理了国家有关部门颁布的有关城市轨道交通发展的政策性文件。城市轨道交通发展的政策变迁反映了我国关于城市轨道交通发展总体思路的变化。 展开更多
关键词 城市轨道交通 发展 政策 变迁
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Reexploration of Structural Changes in Element Bromine through Pressure-Induced Decomposition of Solid HBr
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作者 刘明坤 段德芳 +3 位作者 黄艳萍 梁永福 黄晓丽 崔田 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第8期80-83,共4页
Simple molecular solids have been an important subject in condensed matter physics,particularly for research of pressure-induced molecular dissociation.We re-explore the structural changes of element bromine through p... Simple molecular solids have been an important subject in condensed matter physics,particularly for research of pressure-induced molecular dissociation.We re-explore the structural changes of element bromine through pressure-induced decomposition of solid HBr.The phase changes in HBr are investigated by Raman spectroscopy and synchrotron x-ray diffraction up to 125 GPa at room temperature.By applying pressure,HBr decomposes into solid bromine in the pressure range of 18.7-38 GPa.The solid bromine changes from molecular phase to incommensurate phase at 81 GPa,and finally to monatomic phase at 91 GPa.During the process of pressureinduced molecular dissociation, the intermediate incommensurate phase of element bromine is confirmed for the first time from the x-ray diffraction studies.The decomposition of HBr is irreversible since HBr cannot form again upon pressure decompression. 展开更多
关键词 Reexploration Changes ELEMENT BROMINE
雄安新区建置的历史沿革及其特征 预览
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作者 杨学新 刘洪升 《河北大学学报:哲学社会科学版》 北大核心 2019年第4期131-135,共5页
雄安新区历史悠久,是中华文明的重要组成部分,与燕赵文化一脉相承。自春秋战国时期至2017年新区设立,行政建置兴废分合、治所迁徙、辖属关系逐渐清晰,区域位置的重要性随着社会的发展而变化,并日益凸显和确立起来。
关键词 雄安新区 建置 变迁 特征
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路径演化视角下我国中小企业的发展变迁 预览
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作者 江鸿 石云鸣 《经济论坛》 2019年第6期87-95,共9页
改革开放以来,我国中小企业群体获得了极大发展,成为国民经济的重要力量;中小企业政策逐渐由实践先于政策转向政策引导实践;中小企业群体的发展经历了粗放成长、路径分化和创新发展三个阶段。文章从时间维度对改革开放以来中小企业的发... 改革开放以来,我国中小企业群体获得了极大发展,成为国民经济的重要力量;中小企业政策逐渐由实践先于政策转向政策引导实践;中小企业群体的发展经历了粗放成长、路径分化和创新发展三个阶段。文章从时间维度对改革开放以来中小企业的发展变迁和特征进行纵向剖析,针对新时代中小企业发展的特征和需求,提出未来中小企业持续发展的对策建议。 展开更多
关键词 改革开放 中小企业 发展 变迁
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Clinical and electrophysiological profiles in early recognition of polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes syndrome
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作者 Qin Wang Peng Liu +4 位作者 Li-Li Ji Shuai Wu Guo-Dong Feng Xin Wang Ji-Hong Dong 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第14期1666-1672,共7页
Background:The detection of polyneuropathy,organomegaly,endocrinopathy,M-protein,and skin changes (POEMS) syndrome at early stage is challenging for neurologists.Since polyneuropathy could be the first manifestation,i... Background:The detection of polyneuropathy,organomegaly,endocrinopathy,M-protein,and skin changes (POEMS) syndrome at early stage is challenging for neurologists.Since polyneuropathy could be the first manifestation,it could be misdiagnosed as chronic inflammatory demyelinating polyneuropathy (CIDP).The present study aimed to determine the clinical and electrophysiological features of POEMS syndrome to distinguish from CIDP.Methods:The data of a group of patients with POEMS (n =17) and patients with CIDP (n =17) in Zhongshan Hospital Fudan University from January 2015 to September 2017 were analyzed in this retrospective study.The clinical features,neurological symptoms,and electrophysiological findings were compared between the two groups.Results:Clinically,patients with POEMS demonstrated significantly more neuropathic pain in the lower extremities than patients with CIDP (58.8 % vs.11.8 %,P =0.01).Multisystem features like edema,skin change,organomegaly,and thrombocytosis were also pointed towards the diagnosis of POEMS syndrome.Electrophysiologically,terminal latency index (TLI) was significantly higher in patients with POEMS than that in patients with CIDP (median nerve:0.39 [0.17-0.52] vs.0.30 (0.07-0.69),Z =-2.413,P =0.016;ulnar nerve:0.55 [0.23-0.78] vs.0.42 [0.12-0.70],Z =-2.034,P =0.042).Patients with POEMS demonstrated a higher frequency of absent compound muscle action potential of the tibial nerve (52.9% vs.17.6%,P =0.031),less conduction block (ulnar nerve:0 vs.35.3%,P =0.018),and less temporal dispersion (median nerve:17.6% vs.58.8%,P =0.032) than CIDP group.The combination of positive serum monoclonal protein and high TLI (if either one or both were present) discriminated POEMS from CIDP with a sensitivity of 94.1% and 47.1% and specificity of 76.5% and 100.0%,respectively.Conclusions:POEMS syndrome could be distinguished from CIDP through typical clinical and electrophysiological characteristics in practice.The combination of serum monoclonal protein and high TLI might raise the sensitivity of de 展开更多
关键词 POLYNEUROPATHY Organomegaly ENDOCRINOPATHY M protein and skin changes SYNDROME Chronic inflammatory DEMYELINATING polyradiculoneuropathy Terminal LATENCY index
Seeing the Future
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作者 Li Qing 《中国与非洲:英文版》 2019年第4期52-53,共2页
Wang Wenqi, an eye specialist from east China s Jiangsu Province, has noticed an alarming tendency. An increasing number of children have been developing nearsightedness, or myopia, at a younger age.“Now, due to life... Wang Wenqi, an eye specialist from east China s Jiangsu Province, has noticed an alarming tendency. An increasing number of children have been developing nearsightedness, or myopia, at a younger age.“Now, due to lifestyle changes, there is more strain on the eyes than before. It is common to see children using digital devices for long periods. 展开更多
关键词 FUTURE LIFESTYLE CHANGES
发热待查疾病谱及变迁 预览
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作者 吕昆来 辛小娟 《新发传染病电子杂志》 2019年第4期244-246,共3页
发热是许多疾病常见的临床表现,也是患者就诊的常见原因之一。但是很多发热患者的病因诊断却非常困难,有时甚至无法找到确切病因。发热待查也称为不明原因发热(feverofunkownorigin,FUO),是指持续发热在3周以上,多次检测体温在38.3℃以... 发热是许多疾病常见的临床表现,也是患者就诊的常见原因之一。但是很多发热患者的病因诊断却非常困难,有时甚至无法找到确切病因。发热待查也称为不明原因发热(feverofunkownorigin,FUO),是指持续发热在3周以上,多次检测体温在38.3℃以上,且有1周以上的根据病史、体格检查和常规实验室检查仍然不能明确病因的疾病。发热待查概念的提出为不明原因发热患者的诊治提供了重要的临床思路。近年来随着医疗技术的进步和流行病学的变迁使得发热性疾病的疾病谱也有了相应的变化。为了探讨总结发热待查的病种组成,疾病谱的分布及变迁趋势,为临床诊断提供参考思路。 展开更多
关键词 发热待查 疾病谱 变迁
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The Mediating Effect of Body Dissatisfaction in Association between Obesity and Dietary Behavior Changes for Weight Loss in Chinese Children 预览
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作者 GAO Huai Quan WANG Bang Xuan +4 位作者 SUN Li Li LI Ting WU Lu FU Lian Guo MA Jun 《生物医学与环境科学:英文版》 SCIE CAS CSCD 2019年第9期639-646,共8页
Objective The aim of this study was to analyze the mediating effect of body dissatisfaction in correlation between obesity and dietary behavior changes for weight loss(DBCWL).Methods A total of 680 primary and middle ... Objective The aim of this study was to analyze the mediating effect of body dissatisfaction in correlation between obesity and dietary behavior changes for weight loss(DBCWL).Methods A total of 680 primary and middle school stude nts were in eluded in this study.Their body height,weight,and waistline were effectively measured,and they were also evaluated to assess their body dissatisfaction,perception of dietary behaviors,and DBCWL The correlation among these factors was analyzed using mediating effect models.Results The prevalence of overweight/obesity and abdominal obesity was sign讦icantly higher in males than in females(P<0.05).Overweight/obesity,abdominal obesity,and body dissatisfaction significantly increased the risk for DBCWL(OR=2.57,2.77,and 1.95,respectively).Overweight/obesity and abdominal obesity sign讦icantly in creased the risk for body dissatisfaction(OR=6.00 and 4.70,respectively).Significant mediating effects of body dissatisfaction were observed in correlation between overweight/obesity and DBCWL and between abdominal obesity and DBCWL(OR=2.20 and 1.92,respectively;P<0.05),and the proportions of mediating effects among the total effects were 48.89%and 46.60%,respectively.Conclusion Body dissatisfaction might play an important mediating effect in association between DBCWL and obesity,which indicates that guiding children to correctly recognize their body might be more conducive than promoting obese children toward weight loss through dietary behavior changes. 展开更多
关键词 Children and adolescents OBESITY Body dissatisfaction Dietary behavior changes for weight loss
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水利水电工程变更估价中“适用”和“类似”的争议分析 预览
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作者 章辉 《水利建设与管理》 2019年第7期59-62,共4页
为解决水利水电工程施工合同管理中对变更项目估价原则判定争议较大的问题,采用将变更项目和合同清单项目特征参数对比分析、近似量化分析的方法,得出较为直观的对比结果,用于判定“有适用”“无适用但类似”或“无适用或类似”三种类型... 为解决水利水电工程施工合同管理中对变更项目估价原则判定争议较大的问题,采用将变更项目和合同清单项目特征参数对比分析、近似量化分析的方法,得出较为直观的对比结果,用于判定“有适用”“无适用但类似”或“无适用或类似”三种类型,此方法较为合理且可行,可减少业主、监理和施工单位对变更估计类型判定的争议。参建各方在分析变更类型时,采用此量化、统一的标准来分析,更易达成一致意见。 展开更多
关键词 水利水电工程 变更 适用 类似
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家庭结构变迁对我国武术传承的影响
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作者 孟雅楠 《中华武术(研究)》 2019年第10期59-61,共3页
在过去的几十年内,我国社会结构发生了巨大改变,家庭结构在不同时期也有着不同的特点,这也对我国武术的传承造成了影响。由于家庭结构的改变,那些武术世家越来越不容易将武术传递给下一代,很容易出现断代的情况。基于家庭结构的角度来... 在过去的几十年内,我国社会结构发生了巨大改变,家庭结构在不同时期也有着不同的特点,这也对我国武术的传承造成了影响。由于家庭结构的改变,那些武术世家越来越不容易将武术传递给下一代,很容易出现断代的情况。基于家庭结构的角度来分析我国武术在长期流传的过程中面临的困难,从而提出新的思路进行解决。 展开更多
关键词 家庭结构 变迁 武术传承 影响
唯一不变的是变化本身 2019会议发展趋势分析 预览
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作者 付晓 《中国会展》 2019年第4期60-65,共6页
唯一不变的是变化本身,会议行业的发展趋势一直受到大家关注。本文通过对2018年全球各区域会议行业现状进行分析,对2019年行业发展趋势进行预测,并给会议组织者提出了中肯的建议,供大家借鉴。职位不同各抒己见BCD会议活动全球总裁,斯科... 唯一不变的是变化本身,会议行业的发展趋势一直受到大家关注。本文通过对2018年全球各区域会议行业现状进行分析,对2019年行业发展趋势进行预测,并给会议组织者提出了中肯的建议,供大家借鉴。职位不同各抒己见BCD会议活动全球总裁,斯科特·格拉夫(Scott Graf)指出,我们都知道,变化是一直性的。毫无疑问,如何应对全方位变革可以作为企业崛起的一种优势,或者说是个人和企业的责任。今年的'当前趋势'这个话题,突出了我们在行业中发生的变化和趋势,详细说明了每个地区是如何被影响的。 展开更多
关键词 组织者
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Study on Accumulation and Dynamic Changes of Three Carbohydrates in Jerusalem Artichoke in Natural Habitats 预览
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作者 Lihui WANG Xuemei SUN +1 位作者 Long TAN Yi LI 《农业生物技术:英文版》 CAS 2019年第3期57-63,共7页
Two varieties of Jerusalem artichoke (early maturing variety Qingyu No.1 and middle maturing variety Qingyu No.2),which were bred independently by Research and Development Center of Jerusalem Artichoke,Qinghai Academy... Two varieties of Jerusalem artichoke (early maturing variety Qingyu No.1 and middle maturing variety Qingyu No.2),which were bred independently by Research and Development Center of Jerusalem Artichoke,Qinghai Academy of Agriculture and Forestry,were used as materials,and the content and dynamic changes of three kinds of carbohydrates (sucrose,glucose and fructose) in various organs of Jerusalem artichoke in different periods in two natural habitats (water plain and low hill dry land) were studied.The results showed that the content of the three kinds of carbohydrates in Qingyu No.1 and Qingyu No.2 in the water plain and low hill dry land was relatively high in late June and late August.The total content of the three carbohydrates in Qingyu No.1 peaked earlier than that of Qingyu No.2.The total content of the three carbohydrates in the water plain peaked earlier than that of the low hill dry land.In the whole growth period,the total content of the three carbohydrates in the stems and roots of Jerusalem artichoke was higher than that of the leaves.In the leaves,fructose accumulation was relatively obvious in the whole growth period,and the content was high,followed by glucose.In the stems and roots,fructose content was high,followed by sucrose.In the tubers,glucose accumulation was obvious,and sucrose content was lower than glucose and fructose content.When the tubers were harvested,fructose content was high. 展开更多
关键词 JERUSALEM ARTICHOKE Carbohydrates SUCROSE GLUCOSE FRUCTOSE Dynamic CHANGES
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闽台两岸“走水尪”民俗文化对比研究 预览
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作者 张为 《福建工程学院学报》 CAS 2019年第5期473-477,共5页
“走水尪”是一种产生于闽南地区,随闽南籍移民带到台湾,并在移居地落地生根的特色民俗活动。闽台两地“走水尪”民俗虽一脉相承,但由于文化环境的差异,无论是具体形式还是其文化意义,都产生了差异,展现出截然不同的文化特征。探析这一... “走水尪”是一种产生于闽南地区,随闽南籍移民带到台湾,并在移居地落地生根的特色民俗活动。闽台两地“走水尪”民俗虽一脉相承,但由于文化环境的差异,无论是具体形式还是其文化意义,都产生了差异,展现出截然不同的文化特征。探析这一民俗在两岸之间的传承与变迁,阐明要发挥传统闽南民俗活动的文化纽带作用,推动两岸的文化交流。 展开更多
关键词 走水尪 民俗活动 传承 变迁
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民俗话语中“西游”故事的衍变——以常熟地区“唐僧出身”宝卷为例 预览
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作者 胡胜 《渤海大学学报:哲学社会科学版》 2019年第5期1-5,共5页
万历世德堂百回本《西游记》无疑是文人话语系统的典型代表,与之并行的其实还有一个民俗话语中的“西游”故事。这一故事体系一直有自己的内在发展逻辑,与百回定本似又不似,交互影响,具有极强的艺术生命力。流行于江南常熟的“唐僧出身... 万历世德堂百回本《西游记》无疑是文人话语系统的典型代表,与之并行的其实还有一个民俗话语中的“西游”故事。这一故事体系一直有自己的内在发展逻辑,与百回定本似又不似,交互影响,具有极强的艺术生命力。流行于江南常熟的“唐僧出身”宝卷就是典型个案,从其变化可窥见“西游”故事的传承与衍变及与百回本小说的微妙互动。 展开更多
关键词 《西游记》 “唐僧出身”宝卷 衍变 互动
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Response of Yesso scallop Patinopecten yessoensis to acute temperature challenge:physiological and biochemical parameters 预览
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作者 JIANG Weiwei DU Meirong +5 位作者 FANG Jianguang GAO Yaping MAO Yuze CHEN Qionglin LIN Fan JIANG Zengjie 《海洋湖沼学报(英文)》 SCIE CAS CSCD 2019年第1期321-329,共9页
Water temperature is generally considered to be a major factor aff ecting the physiological and biochemical activities of marine bivalves.Here,the physiological and biochemical responses of Yesso scallop,Patinopecten ... Water temperature is generally considered to be a major factor aff ecting the physiological and biochemical activities of marine bivalves.Here,the physiological and biochemical responses of Yesso scallop,Patinopecten yessoensis,to acute water temperature changes in summer were studied.Scallops were transferred directly to a lower temperature(T dec treatment)(from 23°C to 15°C)or to a higher temperature(T inc treatment)(from 15°C to 23°C)for 72 h,respectively.Results showed that the oxygen consumption and ammonia-N excretion rates of P.yessoensis decreased significantly in the T dec treatment but increased dramatically at 6 h in the T inc treatment(P<0.05).In the T dec treatment,hepatopancreas antioxidant enzyme activities,superoxide dismutase(SOD)and catalase(CAT)activities,increased substantially within 72 h(P<0.05).However,a significant decrease in CAT activity was found at 12 h in the T inc treatment(P<0.01).A significant enhancement of acid phosphatase(ACP)activity and malondialdehyde(MDA)content was detected when scallops were acutely exposed to a temperature of 15°C.The levels of Cu/Zn-SOD gene expression in their gills up-regulated significantly in response to acute temperature changes(P<0.01).These data suggest that acute temperature change aff ects physiological and biochemical functions,and improve our knowledge of P.yessoensis under conditions of thermal stress. 展开更多
关键词 Patinopecten yessoensis ACUTE water TEMPERATURE changes PHYSIOLOGY BIOCHEMICAL activities
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Photothermal biological effects of monomeric erythrocyte using optical tweezers
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作者 鲁浩 吴莹 +3 位作者 谢文菁 唐琦 韩彩芹 刘莹 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第6期59-64,共6页
The changes of mechanical properties and biological activities of monomeric erythrocytes are studied using optical tweezers micromanipulation technology.Firstly,the mechanical properties of irradiated erythrocyte memb... The changes of mechanical properties and biological activities of monomeric erythrocytes are studied using optical tweezers micromanipulation technology.Firstly,the mechanical properties of irradiated erythrocyte membranes are obtained.Weaker power laser irradiation can delay the decay of the mechanical properties of erythrocytes and promote the biological activity of erythrocytes,while higher power laser irradiation damages erythrocytes.The stronger the laser irradiation is,the more obvious and rapid the damage will be.The temperature of the cell surface will be changed by regulating the laser power and irradiation time,so the biological functions of erythrocyte can be controlled.Secondly,the finite element simulation of the temperature change on the cell surface under the condition of laser irradiation is carried out using simulation software,and the precise temperature of the cell surface irradiated cumulatively by a laser with different powers is obtained.Finally,the processes of abscission,unfolding,and denaturation of hemoglobins in erythrocytes at different temperatures due to the photothermal effect are analyzed using the model.The mechanism of laser irradiation on the elasticity of erythrocyte membranes is also obtained. 展开更多
关键词 CHANGES of MECHANICAL properties MONOMERIC erythrocytes is ALSO obtained
Coastal Environmental Changes and Management in China in the Context of Global Changes and Human Activities 预览
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作者 Yunfeng ZHANG Yingying CHEN +2 位作者 Xiaobin HUA Shiqing YAN Lili ZOU 《亚洲农业研究:英文版》 2019年第7期24-30,33共8页
Coastal zone is the complex area with intense sea-land interaction. There are various types, complex environments and developed economy in coastal area of China. Under the influence of global change and human activiti... Coastal zone is the complex area with intense sea-land interaction. There are various types, complex environments and developed economy in coastal area of China. Under the influence of global change and human activities, the ecosystem of coastal zone is vulnerable and has sensitive response to environment changes. The environmental problems of sea-level rising have attached close attention by countries all over the world. As far as regions concerned, relative sea-level rising is more important than theoretical sea-level rising. The relative sea-level rising has resulted in series of environment disasters in coastal area of China, such as coastal erosion, seawater invasion, and floods in coastal lowlands, etc. The flux of sediments transported by rivers into sea is the main material source of marine pollution. The human activities are controlling factors of variations in river sediment loads. Under the influence of high strength development in the upstream region, the results are that the reduction of seagoing sediments in main rivers of China, and damage of coastal material balance. Land-based pollution is the main source of marine pollution. With rapid economic development in China s eastern coastal, pollutants flux into sea increase gradually. The results are that the environmental quality and seawater quality of marine have being deteriorated and pollution is serious increasingly. To meet the land demand of industrialization and urbanization, the sea reclamation has become an effective means to alleviate the contradiction between human and land in coastal area of China. This leads to large-scale reduction of coastal wetland area, and the heavy losses of ecological service value of coastal wetland. To face the environmental changes in coastal area of China and solve the contradiction among population, resources, environment, development, it is required to set up the system concept of man-land-sea relationship, so as to achieve sustainable development. The feasible measures include improving coastal management s 展开更多
关键词 Costal areas ENVIRONMENTAL changes Human ACTIVITIES Integrated management
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