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完善我国流域生态补偿制度的思考——以东江流域为例

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生态环境学报 2010年第3期19卷 751-756页

作者：吴箐汪金武中山大学地理科学与规划学院广东广州510275

上下游对流域生态资源保护做出的贡献与生态利益享有的不平等导致区域间社会经济差距的扩大,需要通过生态补偿制度的建立和完善来实现区域统筹和谐发展,但我国现行生态补偿制度由于行政区界限制、相关法规建设不完善、补偿方式较单一、... 详细信息

上下游对流域生态资源保护做出的贡献与生态利益享有的不平等导致区域间社会经济差距的扩大,需要通过生态补偿制度的建立和完善来实现区域统筹和谐发展,但我国现行生态补偿制度由于行政区界限制、相关法规建设不完善、补偿方式较单一、补偿标准测算困难等原因面临不少问题和困境。以东江流域现行生态补偿措施为视点,分析了当前生态补偿研究实践中存在的问题;进而以此为基点根据流域生态系统的连贯性与人类政治结构分割性之间的矛盾进行反思,提出打破流域行政区界限制,统筹构建流域"生态共同体"的理念;并在此理念指导下,提出采取"政府主导、市场运作"策略。即在明确界定流域范围后,首先由"政府主导"开展全流域综合规划、建立和完善省内流域统管机制、跨省流域生态共享共建统筹协商机制;其次以水质水量、出售许可交易权方式测算"生态共同体"之间核算补偿资金,并结合"市场运作"实施多样化并进补偿方式;同时建立流域生态补偿奖惩制度并将其纳入"生态共同体"干部绩效考核体系,构建流域补偿的长效机制,完善我国流域生态补偿制度。

关键词：生态补偿生态共同体东江流域流域规划

从文献计量学、科学计量学到科学技术计量学——关于科学技术计量学的概念及其研究内容

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图书馆论坛 2003年第6期23卷 151-153页

作者：罗式胜中山大学信息管理系广东广州510275

文献计量学分支学科体系的成功建立为科学计量学的发展提供了坚实的基础。不过从目前国内外的科学计量学研究趋势来看 ,其研究较多是集中在科学领域 ,关于技术领域的计量学研究比较单薄。为此 ,文章试论述科学技术计量学的概念及其研究... 详细信息

文献计量学分支学科体系的成功建立为科学计量学的发展提供了坚实的基础。不过从目前国内外的科学计量学研究趋势来看 ,其研究较多是集中在科学领域 ,关于技术领域的计量学研究比较单薄。为此 ,文章试论述科学技术计量学的概念及其研究的内容等若干问题。

关键词：文献计量学科学计量学科学技术计量学科研投入科研评价布拉德福定律高技术产业

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网络仿真器NS2无线模型的网络编码扩展

系统仿真学报 2011年第9期23卷 1795-1800页

作者：樊凯魏茜陈莹龙冬阳中山大学信息科学与技术学院广州510275

面向单播通信的无线网络编码机制COPE已经引起了越来越多研究者的关注。针对现有网络仿真平台不支持编码模式以及研究COPE机制所基于的试验平台环境难以广泛应用的问题,在网络仿真器NS2的无线模型中引入网络编码层并更改数据包传输流程... 详细信息

面向单播通信的无线网络编码机制COPE已经引起了越来越多研究者的关注。针对现有网络仿真平台不支持编码模式以及研究COPE机制所基于的试验平台环境难以广泛应用的问题,在网络仿真器NS2的无线模型中引入网络编码层并更改数据包传输流程,提出NS2的网络编码扩展的无线模型以支持对COPE机制的应用、改进以及新的无线单播网络编码机制的仿真研究。在该扩展模型上对COPE机制在ad-hoc网络中的性能进行仿真研究,仿真结果验证了该模型的可行性。

关键词：无线网络网络编码 COPE机制仿真软件 NS2

Combined Use of RGD-peptide Modified PLGA and TGF-β1 Gene Transfected MSCs to Improve Cell Biobehaviors in vitro

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Journal of Huazhong university of science and technology(Medical sciences) 2009年第5期29卷 592-598页

作者：李长文郑启新郭晓东全大萍赵洁 Department of Orthopedics Union HospitalTongji Medical CollegeHuazhong University of Science and Technology Institute of Polymer science School of Chemistry and Chemical EngineeringSun Yat-sen University

In order to improve the surface properties of PLGA polymer for a better material/cell interface to modulate the cells behaviors, we prepared a novel three-block copolymer, PLGA-[ASP-PEG], and immobilized an RGD-containing peptide, Gly-Arg-Gly-Asp-Ser-Pro-Cys （GRGDSPC） on the surface of it. Transforming growth factor-β1 （TGF-β1） was transfected into bone marrow stromal cells （MSCs） employed as seeded cells. Cell adhesion, spreading, proliferation and differentiation on this material were investigated. The results showed that the cell adhesive ratio on RGD-modified materials was higher than on un-modified materials （P〈0.05）. The extent of cell spreading was also wider on RGD-modified materials than on un-modified materials. Cell proliferation indices of transfected MSCs were increased as compared with the un-transfected MSCs （P〈0.05）. The ALP activities in the MSCs cultured with RGD-modified materials were higher than on un-modified materials after 14 days （P〈0.05）, and those in transfected MSCs were higher than in un-transfected MSCs （P〈0.05）. It was suggested that the combined use of RGD-modification and TGF-β gene transfection could improve the interaction of biomaterial and cells.

关键词： tissue engineering biomaterial PLGA RGD transforming growth factor β bone marrow stromal cells

基于三项式本原多项式的σ-LFSR实现方案

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武汉大学学报（理学版） 2008年第5期54卷 525-529页

作者：王泽辉中山大学数学与计算科学学院广东广州510275

在系数属于有限域的多项式环即有限环上,给出确定型的不可约多项式和本原多项式.利用这些多项式构造一个高效算法,可获得最长周期的输出序列,确定序列的每个值仅耗费2(lbp)次模p加法.给出了一种基于三项式本原多项式的σ-LFSR实现方案.... 详细信息

在系数属于有限域的多项式环即有限环上,给出确定型的不可约多项式和本原多项式.利用这些多项式构造一个高效算法,可获得最长周期的输出序列,确定序列的每个值仅耗费2(lbp)次模p加法.给出了一种基于三项式本原多项式的σ-LFSR实现方案.理论分析和计算机模拟结果显示,该σ-LFSR发生器具有优良的随机性并且便于软硬件的实现.结论可用于建立序列密码的新型高效密码体制.

关键词： σ-LFSR 三项式不可约多项式本原多项式序列密码快速算法

NEW ID-BASED GROUP SIGNATURE FROM PAIRINGS

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Journal of Electronics(china) 2006年第6期23卷 892-900页

作者： Chen Xiaofeng Zhang Fangguo Kwangjo Kim school of information science and technology Sun Yat-sen University Guangzhou 510275 China International Research Center for information Security Information and Communications University Taejon 305-714 Korea

We argue that traditional identity-based systems from pairings seem unsuitable for designing group signature schemes due to the problem of key escrow. In this paper we first propose new ID-based public key systems without trusted PKG (Private Key Generator) from bilinear pairings. In our new ID-based systems, if the dishonest PKG impersonates an honest user to communicate with others, the user can provide a proof of treachery of the PKG afterwards, which is similar to certificate-based systems. Therefore, our systems reach the Girault’s trusted level 3. We then propose a group signature scheme under the new ID-based systems, the security and performance of which rely on the new systems. The size of the group public key and the length of the signature are independent on the numbers of the group.

关键词： Group signature Bilinear pairings Identity-based cryptography

A Population-based Study of Lens Opactities

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Eye science 1996年第3期16卷 115-117页

作者： Jingjing Xu, Qiang Yu, Siping Zhu, Qing LiuZhongshan Ophthalmic Center, sun yat-sen university of Medical sciences,guangzhou 510060,china Zhongshan Opthalmic Center Sun Yat-sen University of Medical Sciences Guangzhou China.

Purpose: Age-related lens opacity is the main cause of vision disablitity in elderly population all over the world. This study was designed to investigate the prevalence and incidence of lens ***: 1817 eyes of 932 adults over 45 year-old were sampled randomly from 4 villeges within Doumen, a county located in the south of Guangdong provience, china. The procedure of the examination was performed by ophthalmologists. The lens opacities were graded according to a standarized photo of the Lens Opacities Classification System II (LOGS- II ).Results: The prevalence of lens opacities in nuclear color, nuclear opacity, cortical opacity and subcapsular opacity was 16. 1% , 28.,6% , 30. 3% and 8. 7% , respectively. The frequency of all four types of opacities increased with age. The prevalence of lens opacities in four types was higher in female than that in male. Conclusion: The data we got are important for prevalence of lens opacities of population-based study as well as basic information for

关键词： lens opacities epidemiology

Tetramethylpyrazine protected photoreceptor cells of rats by modulating nuclear translocation of NF-κB

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Acta Pharmacologica Sinica 2005年第7期26卷 887-892页

作者： Jin-nan YANG~(2,3) Jin-mao CHEN~4 Lin LUO~4 Shao-chun LIN~4 Dai LI~4 Shi-xing HU~(4,5,6) 2 school of Pharmacy,Xinxiang Medical College,Xinxiang 453003,china 4 Zhongshan Ophthalmic Centre,sun yat-sen university,guangzhou 510060,china 5 Eye Hospital of china,Academy of Traditional Chinese Medicine,Beijing 100040,china school of Pharmacy Xinxiang Medical College Xinxiang China Zhongshan Ophthalmic Centre Sun Yat-sen University Guangzhou China Eye Hospital of china Academy of Traditional Chinese Medicine Beijing China

Aim:To evaluate the effect of tetramethylpyrazine(TMP)injection on retinaldamage induced by N-methyl-N-nitrosourea(MNU)in rats and on nuclear factor-kappa B(NF-κB)family ***:Female Sprague-Dawley(SD)ratswere randomly divided into groups:(i),control group;(ii),model group;and(iii),TMP-injection groups,in which the rats were subdivided into 40 mg/kg,80 mg/kgand 160 mg/kg *** were injected ip into 47-day-old SD rats once a *** 50 days of age,all rats in the model group and drug groups also received asingle ip injection of 60 mg/kg *** in group 1 received ip injection ofphysiological *** rats were killed at different times after MNU or physi-ological saline *** apoptotic index of photoreceptor cells was calcu-lated by TUNEL labeling;retinal damage was evaluated based on retinal thicknessand the expression of NF-κB family members was detected by Western ***:TMP injections,in a dose-dependent manner,suppressed photorecep-tor cell apoptosis and decreased its loss in the peripheral *** comparedwith the MNU-treated group,TMP injection at a dose of 160 mg/kg also time-dependently upregulated the NF-κB/p65 protein level in the nucleus anddownregulated the IκBα protein level in the ***,no protectiveeffect of TMP injection on MNU-induced central retinal damage was ***:TMP injection partially protects against MNU-induced retinal dam-age by upregulating the nuclear translocation of p65 to inhibit photoreceptor cellsapoptosis.

关键词： tetramethylpyrazine photoreceptors methylnitrosourea apoptosis NF-kappa B retinitis pigmentosa

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人工感染的刺激隐核虫各期虫体的超微结构

水产学报 2005年第5期29卷 53-60页

作者：黄玮马跃中山大学生命科学学院中山大学生命科学学院广东广州510275 广东省水产学校广东广州510320 西南农业大学动物科学学院重庆402460

从天然感染的卵圆鲳(Trachinotus blochii)分离到1株刺激隐核虫(Cryptocaryon irritans),再经人工感染的方法收集各期虫体,制成电镜样品,对虫体进行超微结构研究。刺激隐核虫质膜的基本结构与淡水的多子小瓜虫的质膜相似,分为3层:外限... 详细信息

从天然感染的卵圆鲳(Trachinotus blochii)分离到1株刺激隐核虫(Cryptocaryon irritans),再经人工感染的方法收集各期虫体,制成电镜样品,对虫体进行超微结构研究。刺激隐核虫质膜的基本结构与淡水的多子小瓜虫的质膜相似,分为3层:外限制膜、外胞膜和内胞膜。刺激隐核虫的质膜小泡内充满大量电子致密物质(EDM)。幼虫、幼体和滋养体均具有复杂的口器,由胞咽、口肋、双动基体口纤毛和线带等组成,但不具备膜口类纤毛虫所具有的独特的细胞器:Lieberkuhn氏器。单动基体的体纤毛存在于幼虫、幼体和滋养体,但在包囊期,体纤毛和口器消失。各期虫体的胞质中具有线粒体、高尔基体和脂肪体等细胞器,有的阶段具有粘液囊、伸缩泡、食物泡、共生细菌等。粘液囊在大小、形态和分布上与多子小瓜虫的不同。文中分析了刺激隐核虫在形态上与多子小瓜虫的诸多差异,认为刺激隐核虫的分类更适合归于原口类(Promotome),而不是膜口类(Ophryoglenina)。

关键词：刺激隐核虫超微结构人工感染