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Science china(life sciences) 2010年第4期53卷 462-470页

作者： LI WenSheng & LIN HaoRan State Key laboratory of Biocontrol, Institute of Aquatic Economic Animals and the Guangdong Provincial Key laboratory for Aquatic Economic Animals, School of life sciences, sun yat-sen university, guangzhou 510275, china 1. State Key laboratory of Biocontrol Institute of Aquatic Economic Animals and the Guangdong Provincial Key Laboratory for Aquatic Economic Animals School of Life Sciences Sun Yat-sen University Guangzhou 510275 China

In teleosts, growth hormone (GH) production is governed by multiple neuroendocrine factors from the hypothalamus and other regulators from the pituitary and peripheral organs. Exploring the principles followed by pituitary somatotropes when differentiating and integrating the signals from these regulators at the cellular and intracellular level is essential for understanding the endocrine regulation network of growth hormone synthesis and secretion in fish. This paper discusses recent advances in the action mechanisms of GH regulation factors, including the neuroendocrine regulators, pituitary level factors and peripheral factors, primarily involved in their receptor systems as well as in post-receptor signal transduction pathways.

关键词： fish growth hormone receptor signal transduction

NUMERICAL MODELING OF WAVE EVOLUTION AND RUNUP IN SHALLOW WATER

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Journal of Hydrodynamics 2009年第6期21卷 731-738页

作者： DONG Zhi ZHAN Jie-min Department of Applied Mechanics and Engineering Sun Yat-sen University Guangzhou 510275 China Guangdong Province Key laboratory of Coastal Ocean Engineering Sun Yat-sen University Guangzhou 510275China

Based on the Navier-Stokes （N-S） equations for viscous, incompressible fluid and the VOF method, 2-D and 3-D Numerical Wave Tanks （NWT） for nonlinear shallow water waves are built. The dynamic mesh technique is applied, which can save computational resources dramatically for the simulation of solitary wave propagating at a constant depth. Higher order approximation for cnoidal wave is employed to generate high quality waves. Shoaling and breaking of solitary waves over different slopes are simulated and analyzed systematically. Wave runup on structures is also investigated. The results agree very well with experimental data or analytical solutions.

关键词： VOF method shallow water waves wave evolution wave runup

Chemical weathering and chemical runoffs in the seashore granite hills in South china

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Science china Earth sciences 2010年第8期53卷 1195-1204页

作者： GAO QuanZhou & TAO Zhen School of Geography and Planning, sun yat-sen university, guangzhou 510275, china 1. School of Geography and Planning Sun Yat-sen University Guangzhou 510275 China

Surface runoffs and the contents of major ions and dissolved silicon were surveyed and analyzed based on weekly sampling for one year in a granite watershed of Zhuhai City, Guangdong Province. The results demonstrated that the slope runoff played an essential role in feeding the rivulet during precipitation, whereas the groundwater was more important for the rivulet in the non-raining stages. Dissolved silicon, Na+, HCO3-, and Clions constituted the major chemical components of the rivulet water. Atmospheric CO2 and H2SO4 sourced from the oxidation of pyrite were the main erosive mediums in the natural chemical weathering. Natural chemical weathering, the wet and dry deposition of sea-salt, and acids precipitation contributed approximately equal shares of anions to the rivulet water. The ratio of NO3- to SO42- was more than 1.0 in the runoff of the studied seashore watershed, whereas it is less than 1.0 in the Xijiang River that is adjacent to the study area. This implied that the chemical composition of runoff is controlled mainly by the differences in atmospheric acid precipitation caused by human activities and lithology within the catchments under the same bio-climate zone. The CO2 flux consumed by the rock chemical weathering processes within the seashore granite watershed in South china was (0.35-1.37)×105 mol km-2 a-1.

关键词： chemical weathering granite ion sea-salt acid deposition CO2

On the diophantine equation X^2-(1+a^2)Y^4 =-2a

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Science china Mathematics 2010年第8期53卷 2143-2158页

作者： YUAN PingZhi 1 & ZHANG ZhongFeng 2 1 School of Mathematics,South china Normal university,guangzhou 510631,china 2 School of Mathematics & Computational Science,sun yat-sen university,guangzhou 510275,china 1. School of Mathematics South China Normal University Guangzhou 510631 China2. School of Mathematics & Computational Science Sun Yat-Sen University Guangzhou 510275 China

Let a≥1 be an *** this paper,we will prove the equation in the title has at most three positive integer solutions.

关键词： algebraic approximations continued fractions elliptic curves quartic equations

Tetrabromobisphenol A and hexabromocyclododecane in sediments from the Zhujiang(Pearl) River Estuary and South china Sea

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Acta Oceanologica Sinica 2024年第6期43卷 32-37页

作者： Chuyue Long Weiyan Yang Jiaxun Lu Yuanyue Cheng Ning Qiu sen Du Li Zhang Shejun Chen Yuxin sun Guangdong Provincial Key laboratory of Chemical Pollution and Environmental Safety/Key laboratory of Theoretical Chemistry of Environmental of Ministry of Education School of EnvironmentSouth China Normal UniversityGuangzhou 510006China South china Sea Institute of Oceanology Chinese Academy of SciencesGuangzhou 510301China Research Center of Harmful Algae and Marine biology Jinan UniversityGuangzhou 510632China university of Chinese Academy of sciences Beijing 100049China Southern Marine Science and Engineering Guangdong laboratory Guangzhou 511458China

Marine sediments collected from the Zhujiang(Pearl) River Estuary(ZRE) and South china Sea(SCS) were utilized to study the occurrence and spatial distribution of tetrabromobisphenol A(TBBPA) and hexabromocyclododecane(HBCDD).The levels of TBBPA and HBCDD in sediments ranged from not detected(nd) to 6.14 ng/g dry weight(dw) and nd to 0.42 ng/g *** concentrations in marine sediments were substantially higher than *** concentrations of TBBPA and HBCDD in the ZRE sediments were significantly greater than those in the SCS.α-HBCDD(48.7%) and γ-HBCDD(46.2%) were the two main diastereoisomers of HBCDD in sediments from the ZRE,with minor contribution of β-HBCDD(5.1%).HBCDD were only found in one sample from the northern *** enantiomeric fraction of α-HBCDD in sediments from the ZRE was obviously greater than 0.5,indicating an accumulation of(+)-α-*** enantiomers of HBCDD were not measured in sediments from the *** work highlighted the environmental behaviors of TBBPA and HBCDD in marine sediments.

关键词： tetrabromobisphenol A hexabromocyclododecane marine sediments Zhujiang River Estuary South china Sea

Interferon-α enhances sensitivity of human osteosarcoma U2OS cells to doxorubicin by p53-dependent apoptosis

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Acta Pharmacologica Sinica 2007年第11期28卷 1835-1841页

作者： Xiang-wei YUAN~2,Xiao-feng ZHU~(3,5),Xiu-fang HUANG~4,Pu-yi SHENG~2,Ai-shan HE~2,Zi-bo YANG~2,Rong DENG~3,Gong-kanFENG~3,Wei-ming LIAO~(2,5)~2 Department of Orthopedic Surgery,The First Affiliated Hospital,sun yat-sen university,guangzhou 510080,china ~3 State Key laboratoryof Oncology in South china,Cancer Center,sun yat-sen university,guangzhou 510060,china ~4 Department of Pathology,The AffiliatedJiangmen Hospital,sun yat-sen university,Jiangmen 529030,china Department of Orthopedic Surgery The First Affiliated Hospital Sun Yat-sen University Guangzhou 510080 China State Key laboratory of Oncology in South china Cancer Center Sun Yat-sen University Guangzhou 510060 China Department of Pathology The Affiliated Jiangmen Hospital Sun Yat-sen University Jiangmen 529030 China

Aim:To determine whether interferon-α(IFNα) can enhance doxorubicinsensitivity in osteosarcoma cells and its molecular ***:Cellviability was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide *** was studied using Flow cytometry analysis,Hoechst33258 staining,DNA fragmentation assay,as well as the activation ofcaspase-3 and poly (ADP-ribose) *** expression was detectedby Western *** dependence of p53 was determined using ***:IFNα increased doxorubicin-induced cytotoxicity to a muchgreater degree through apoptosis in human osteosarcoma p53-wild U2OS cells,but not p53-mutant MG63 ***α markedly upregulated p53,Bax,Mdm2,andp21,downregulated Bcl-2,and activated caspase-3 and PARP cleavage in re-sponse to doxorubicin in U2OS ***,the siRNA-mediated silencing ofp53 significantly reduced the IFNα/doxorubicin combination-induced cytotoxic-ity and PARP ***:IFNα enhances the sensitivity of humanosteosarcoma U2OS cells to doxorubicin by p53-dependent *** propercombination with IFNα and conventional chemotherapeutic agents may be a ra-tional strategy for improving the treatment of osteosarcoma with functional p53.

关键词： Interferon-α doxorubicin apoptosis p53 osteosarcoma

Reflection of plane electromagnetic waves from the surface of a perfect conductor moving in an arbitrary direction

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Chinese Science Bulletin 2000年第17期45卷 1564-1569页

作者： HE Qicai & HUANG Yaoxiong1. Department of Physics, sun yat-sen university of Medical sciences, guangzhou 510089, china 2. Institute of Biomedical Engineering, Ji’nan university, guangzhou 510632, china Correspondence should be addressed to Huang Yaoxiong Department of Physics Sun Yat-sen University of Medical Sciences Guangzhou China Institute of Biomedical Engineering Ji’nan University Guangzhou China

The reflection of plane electromagnetic waves (TE wave and TM wave) from a perfect conductor which moves in an arbitrary direction is investigated. Based on Maxwell’s equations and the boundary conditions for moving boundary, the relation between the field vectors of reflected and incident waves, and the reflection coefficient are derived. The energy balance between incident and reflected waves, the force exerted by electromagnetic waves to the moving conductor are also discussed and some new conclusions are suggested for notice.

关键词： plane electromagnetic wave moving conductor reflection coefficient radiation pressure.

Fringe View: Problems and Construction of Human Settlement Environment for "Village-in-City"

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Chinese Journal of Population,Resources and Environment 2005年第1期3卷 18-26页

作者： Mo Chuangrong , Li Xia , Wang Shugong 1 1,2 & Chen Xingeng 1 1. Institute of Environmental sciences, sun yat-sen university, guangzhou Guangdong 510275, china 2. Center of Earth Environment & Resources, sun yat-sen university, guangzhou Guangdong 510275, china Institute of Environmental sciences Sun Yat-Sen University Guangzhou Guangdong 510275 China Center of Earth Environment & Resources Sun Yat-Sen University Guangzhou Guangdong 510275 China

The construction of human settlement environment is one of the important contents in the domain of sustainable development. We try to annotate human settlement environment for "village- in-city" from the angle of fringe view. According to the macro-system thought of human settlement environment science, the evolvement, which can be generalized into four phases, connotation and problems (including social, economic, and environmental problems) of "village-in-city" are discussed primarily in this paper. Some domestic and international researches and practices are also summarized and assessed in the paper. Based on the analysis, some appropriate clues and suggestions for the construction of "village-in-city" have been put forward.

关键词： human settlement environment urbanization "village-in-city" fringe view sustainable development

Uncertainty,Irreversibility and the Timing Problems of Environmental Policy

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Chinese Journal of Population,Resources and Environment 2006年第4期4卷 29-37页

作者： Yang Haisheng1,Jia Jia1,Zhou Yongzhang2 1.Lingnan college,sun yat-sen university,guangzhou Guangdong 510275,china 2.Center for Earth Environment&Resources,sun yat-sen university,guangzhou Guangdong 510275,china Lingnan college Sun Yat-sen University Guangzhou Guangdong 510275 China Lingnan College Sun Yat-sen University Guangzhou Guangdong 510275 China Center for Earth Environment & Resources Sun Yat-sen University Guangzhou Guangdong 510275 China

Most environmental issues and policy designing are uncertain and irreversible;therefore,the timing of environmental policy implementation becomes especially *** paper establishes a random dynamic programming model and analyzes the optimal timing problems in environmental policy under uncertain *** model results indicate that two variables have a significant impact on the timing of environmental policy implementation and they work in opposite directions:on one hand,the more uncertain the economy is,the higher the cost of policies implementation will be,and consequently the incentive to immediately adopt the policy will be *** the other hand,the higher the uncertainty of the environment is,the stronger the irreversibility of ecological harm caused by pollutants per unit will ***,the government should implement new environmental policies as early as possible in order to gain more ecological benefits.

关键词： environmental policy uncertainty irreversibility timing

A distribution space for Hilbert transform and its applications

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Science china Mathematics 2008年第12期51卷 2217-2230页

作者： YANG LiHua School of Mathematics and Computing Science, sun yat-sen university, guangzhou 510275, china School of Mathematics and Computing Science Sun Yat-Sen University Guangzhou 510275 China

In this paper, a new distribution space is constructed and the definition of the classical Hilbert transform is extended to it. It is shown that is the biggest subspace of on which the extended Hilbert transform is a homeomorphism and both the classical Hilbert transform for L p functions and the circular Hilbert transform for periodic functions are special cases of the extension. Some characterizations of the space are given and a class of useful nonlinear phase signals is shown to be in . Finally, the applications of the extended Hilbert transform are discussed.

关键词： Hilbert transform distribution time-frequency analysis 44A15 46F12