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Frontiers of Mathematics in China 2020年第3期15卷 467-489页

作者： linlin fu Jiahao XU Fan WU Department of Mathematics Sun Yat-sen UniversityGuangzhou 510275China Chern Institute of Mathematics and LPMC Nankai UniversityTianjin 300017China Department of Mathematics Nanjing UniversityNanjing 210093China

We reconsider the continuity of the Lyapunov exponents for a class of smooth Schrödinger cocycles with a C2 cos-type potential and a weak Liouville *** propose a new method to prove that the Lyapunov exponent is conti... 详细信息

关键词： Schrodinger cocycle Lyapunov exponent(LE) weak Liouville frequency C2 cos-type potential large deviation theorem(LDT)

An inventory model under two-level trade credit when demand is stimulated by stock level

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An inventory model under two-level trade credit when demand ...

Major reactive species of ambient volatile organic compounds (VOCs) and their sources in Beijing

第25届中国控制与决策会议

作者： Mo Jiangtao fu linlin Li Zhonghui Hao Jiaqin College of Mathematics and Information Sciences Guangxi University

ISBN: (纸本)9781467355339

An inventory model for deteriorating item under two-level trade credit is presented. The demand rate is a linear function of the inventory level if it is more than a certain amount;otherwise the demand rate is a constant. The optimal cycle and order quantity are determined. Numerical examples are given to illustrate the theoretical results. Sensitive analysis of major parameters has been carried out and the implications are discussed.

关键词： inventory model two-level trade credit deteriorating items stock-dependent demand

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Science China Earth Sciences 2005年第Z2期48卷 147-154页

作者： SHAO Min fu linlin LIU Ying LU Sihua ZHANG Yuanhang TANG Xiaoyan State Joint Key Laboratory of Environmental Simulation and Pollution Control College of Environmental SciencesPeking UniversityBeijing 100871China

Volatile organic compounds(VOCs)are important precursors of atmospheric chemical *** a whole mixture,the ambient VOCs show very strong chemical *** on OH radical loss rates in the air,the chemical reactivity of VOCs in Beijing was *** results revealed that alkenes,accounting for only about 15%in the mixing ratio of VOCs,provide nearly 75%of the reactivity of ambient VOCs and the C4 to C5 alkenes were the major reactive species among the *** study of emission characteristics of various VOCs sources indicated that these alkenes are mainly from vehicle exhaust and gasoline *** reduction of alkene species in these two sources will be effective in photochemical pollution control in Beijing.

关键词： alkenes radicals vehicle exhaust gasoline evaporation.

Inducible regulation of GDNF expression in human neural stem cells

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Science China(Life Sciences) 2013年第1期56卷 32-39页

作者： WANG ShuYan REN Ping GUAN YunQian ZOU ChunLin fu linlin ZHANG Yu Cell Biology Room Xuanwu HospitalCapital Medical Universityand Key Laboratory of NeurodegenerationMinistry of Education

Glial cell derived neurotrophic factor （GDNF） holds promises for treating neurodegenerative diseases such as Parkinson＇s dis- ease. Human neural stem cells （hNSCs） have proved to be a suitable cell delivery vehicle for the safe and efficient introduction of GDNF into the brain. In this study, we used hNSCs-infected with a lentivirus encoding GDNF and the hygromycin re- sistance gene as such vehicles. A modified tetracycline operator 7 （tetO7） was inserted into a region upstream of the EFI-α promoter to drive GDNF expression. After hygromycin selection, hNSCs were infected with a lentivirus encoding a KRAB-tetracycline repressor fusion protein （TTS）. TTS bound to tetO7 and suppressed the expression of GDNF in hNSCs. Upon administration of doxycycline （Dox） the TTS-tetO7 complex separated and the expression of GDNF resumed. The hNSCs infected with GDNF expressed the neural stem cell specific markers, nestin and sox2, and exhibited no significant change in proliferation rate. However, the rate of apoptosis in hNSCs expressing GDNF was lower compared with normal NSCs in response to actinomycin treatment. furthermore, a higher percentage of Tuj-I positive cells were obtained from GDNF-producing NSCs under conditions that induced differentiation compared to control NSCs. The inducible expression of GDNF in hNSCs may provide a system for the controllable delivery of GDNF in patients with neurodegenerative diseases.

关键词： neural stem cells GDNF lentivirus vectors tetracycline operator

On the Stability of Orthogonal Additivity in β-Homogeneous F-Spaces

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Journal of Mathematical Research with Applications 2022年第3期42卷 289-296页

作者： Qi LIU linlin fu Yongjin LI Department of Mathematics Sun Yat-sen University

In this paper, we study the stability of the orthogonal equation, which is closely related to the results by W. Fechner and J. Sikorska in 2010. There are some differences that we consider the target space with the β-homogeneous norm and quasi-norm. Overcoming theβ-homogeneous norm and quasi-norm bottlenecks, we get some new results.

关键词： Hyers-Ulam stability β-homogeneous F-spaces quasi-Banach spaces orthogonal additivity

On the Behavior of the Positive Solutions of the System of Two Higher-Order Rational Difference Equations

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Applied Mathematics 2013年第8期4卷 1220-1225页

作者： Qi Wang Gengrong Zhang linlin fu College of Mathematics and Information Science Guangxi University Nanning China College of Science Guangxi University of Science and Technology Liuzhou China

We study the convergence of the positive solutions of the system of the following two difference equations: where K is a positive integer, the parameters?A,B,?α, β? and the initial conditions are positive real numbe... 详细信息

关键词： System of Difference Equations Convergence Positive Solution Behavior

Health literacy of college students in Beijing and the demands of health education

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China Population and Development Studies 2020年第5期4卷 213-228页

作者： Jing Guo Yumeng Guo Lin Zhu linlin fu Institute of Health Sciences Research School of Sociology and Population StudiesRenmin University of ChinaBeijing 100872China

Health literacy is the main component of health quality and a comprehensive health indicator reflecting related idea,cognition,behavior and *** this paper,we investigated the overall level and characteristics of health literacy based on the survey data of college students in *** differences of health literacy level among sub-groups were compared,and the influencing factors of health literacy were *** results showed that college students had a higher level in overall health literacy than other peers,but a lower level in the prevention of chronic disease and infectious *** level of health literacy of college students was mainly affected by their major,hometown,and situation of health-related ***,we also found that the way college students used to acquire health knowledge was inconsistent with their expectations,and the requirements for health education were also very *** systematic and comprehensive health education should be provided in universities,with an emphasis on the knowledge of lifestyle and daily habits.

关键词： College student Health literacy Influencing factors Demand

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新型农业经营体系的内涵与建构

学术月刊 2015年第7期47卷 50-56页

作者：黄祖辉傅琳琳浙江大学中国农村发展研究院教授浙江杭州310058

新型农业经营体系构建问题已成为当前政府和学界关注的一个热点问题。新型农业经营体系的科学内涵需从多维度、多层次角度进行把握,并且从横向、纵向、区域三个维度进行观察。新型农业经营体系应该是现代农业产业体系、组织(主体)体系... 详细信息

新型农业经营体系构建问题已成为当前政府和学界关注的一个热点问题。新型农业经营体系的科学内涵需从多维度、多层次角度进行把握,并且从横向、纵向、区域三个维度进行观察。新型农业经营体系应该是现代农业产业体系、组织(主体)体系、制度体系和网络体系的集合体。产业组织与组织制度的选择和安排是新型农业经营体系的关键。在建构过程中,要合理运用农业股份合作制和土地股份合作制,处理好农业家庭经营和企业经营的关系,防止新型农业主体培育中的主体异化。此外,要注重多类型农业规模经营与多元化服务体系的相互协调,把握农业规模经营的适度性和多样性,处理好服务外包化与内部化、服务公平与效率的关系。最后,在新型农业经营体系构建中,要深化农村土地产权制度与集体经济制度的改革,尽快建立农民土地承包权有偿退出和市场交易机制,改革现行农村集体经济制度。

关键词：新型农业经营体系改革规模经营服务体系土地产权

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我国乡村建设的关键与浙江“千万工程”启示

华中农业大学学报（社会科学版） 2021年第3期 4-9,182页

作者：黄祖辉傅琳琳浙江大学中国农村发展研究院浙江杭州310058 浙江省农业科学院农村发展研究所浙江杭州310021

习近平总书记强调,要实施乡村建设行动,继续把公共基础设施建设的重点放在农村,在推进城乡基本公共服务均等化上持续发力,注重加强普惠性、兜底性、基础性民生建设。在阐述我国乡村建设内涵与特点的基础上,提出了乡村建设的三个重要关键... 详细信息

习近平总书记强调,要实施乡村建设行动,继续把公共基础设施建设的重点放在农村,在推进城乡基本公共服务均等化上持续发力,注重加强普惠性、兜底性、基础性民生建设。在阐述我国乡村建设内涵与特点的基础上,提出了乡村建设的三个重要关键,一是既要坚持政府主导,又要引入市场力量;二是既要解决有效供给,又要重视有效管护;三是既要防止大拆大建,又要避免低效配置。在阐释浙江“千万工程”实践及其经验基础上,提出了浙江“千万工程”对我国乡村建设的启示,即在农村社区人居环境建设和治理中,应探索建立“四位一体”的治理体系,也就是“党政合一”的科层治理、“智治合一”的精准治理、“调动群众”的柔性治理以及“激励相容”的市场治理,以充分发挥不同制度对行为主体在乡村社区公共品供给和营运管护中的激励与约束作用。

关键词：乡村建设 “千万工程” 农村社区公共品乡村治理社会制度

贫困地区农户参与合作社的行为机理分析——来自广西富川县的经验

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农业经济问题 2018年第11期39卷 134-144页

作者：朋文欢傅琳琳宁波大学商学院宁波315211 浙江省农业科学院农村发展研究所杭州310021

本文从农户入社需求和合作社吸纳意愿两个视角对农户入社的行为机理进行了理论解读和实证检验。广西富川县的经验表明,农户能否入社不仅取决于农户的入社需求,更有赖于合作社对其的吸纳意愿。然而,双变量Probit模型的验证结果显示,农户... 详细信息

本文从农户入社需求和合作社吸纳意愿两个视角对农户入社的行为机理进行了理论解读和实证检验。广西富川县的经验表明,农户能否入社不仅取决于农户的入社需求,更有赖于合作社对其的吸纳意愿。然而,双变量Probit模型的验证结果显示,农户与合作社在决策中关注的焦点迥异,前者希望入社以改善其贫困弱势,节约交易费用并规避经营风险,因此,贫困建档立卡户或有专用性投资的农户入社更积极;后者对贫困户并未表现出青睐,经营规模大、有专用性投资或以非粮作物经营为主的农户才是其吸纳重点。二者期许的“鸿沟”构成了农户入社意愿难以向实际入社行为转换的主因。人际关系、邻里行为也是合作社与农户决策的重要参考。比较可发现依据单变量二值选择模型的结果可能会对农户的行为机制做出错误解读。

关键词：农民合作社农户行为机理入社需求吸纳意愿贫困地区