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Modeling the intracellular dynamics for Vif-APO mediated HIV-1 virus infection

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chinese Science Bulletin 2010年第22期55卷 2329-2340页

作者： WANG Yi1,2 & LAI LuHua1,3 1 Center for theoretical Biology, Peking University, beijing 100871, china 2 School of physics, Peking University, beijing 100871, china 3 BNLMS, State key laboratory for Structural Chemistry of Unstable and Stable Species, College of Chemistry and Molecular Engineering, Peking University, beijing 100871, china Center for theoretical Biology Peking University Beijing China School of physics Peking University Beijing China BNLMS State Key Laboratory for Structural Chemistry of Unstable and Stable Species College of Chemistry and Molecular Engineering Peking University Beijing China

The viral infectivity factor (Vif) was found to be essential for controlling HIV-1 virus infectivity. It targets cellular antiviral proteins in APOBEC family (APO) to trigger its fast degradation and inhibits APO packaging into nascent virion. In the present study, we propose a mathematical model to quantitatively study the intracellular dynamics of these typical virus-host interactions. Four sets of published experimental data were compared with simulation results to justify the model. Systematic parameter sensitivity and perturbation analysis showed that parameters related to APO are crucial to the infectivity of newly synthesized HIV-1 virus. Interestingly, we discovered that the synthesis rate of the viral structure protein Gag and the required number per nascent virion are optimized to achieve high virion production with minimal level of packaged APO, and large portion of model parameters are beneficial to virus only within a relatively small range. Furthermore, minor variations in several parameters related to viral protein Tat, the activator of viral RNA synthesis, were found to induce switch-like behaviors on both incorporated Vif and APO. These findings may provide new insights for understanding the high mutation rate of HIV-1 virus and its latency, as well as help identify key targets for therapeutic design.

关键词：病毒感染载脂蛋白 HIV 细胞内动力学抗病毒蛋白建模介导

Identification of ten new Galactic HII regions

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Science china(physics,Mechanics & Astronomy) 2010年第6期53卷 1144-1152页

作者： RUAN GuiPing 1,2 & SHI WeiBin 1,2 1 Shandong Provincial key laboratory of Optical Astronomy and Solar-Terrestrial Environment,School of Space Science and physics,Shandong University at Weihai,Weihai 264.09,china 2 key laboratory of Optical Astronomy,National Astronomical Observatories,chinese Academy of sciences,beijing 100012,china Shandong Provincial key laboratory of Optical Astronomy and Solar-Terrestrial Environment School of Space Science and Physics Shandong University at Weihai Weihai China key laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing China

We discovered ten large HII regions in the Sino-German λ6 cm polarization survey of the Galactic plane. They have been identified according to their flat spectral indexes and the high ratio between the 60 μm infrared emission and the λ6 cm emission. The integrated flux densities as well as the sizes of these sources are given at 4.00 MHz. Cross-identifications are made with other major radio catalogs.

关键词： radio continuum general-methods observational-HII regions

An Extended Subequation Rational Expansion Method and Solutions of (2+1)-Dimensional Cubic Nonlinear Schr(?)dinger Equation

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Communications in theoretical physics 2007年第12期48卷 987-992页

作者： GUO Wei-Ming~1 LI Biao~(1,3)and CHEN Yong~(1,2,3)~1 Nonlinear Science Center and Department of Mathematics,Ningbo University,Ningbo 315211,china~2 institute of theoretical Computing,East china Normal University,Shanghai 200062,china~3 key laboratory of Mathematics Mechanization,the chinese Academy of sciences,beijing 100080,china Nonlinear Science Center and Department of Mathematics Ningbo University Ningbo 315211 China key laboratory of Mathematics Mechanization the Chinese Academy of Sciences Beijing 100080 China institute of theoretical Computing East China Normal University Shanghai 200062 China

An extended subequation rational expansion method is presented and used to construct some exact,analyt-ical solutions of the (2+1)-dimensional cubic nonlinear Schrdinger *** our results,many known solutionsof the (2+1)-dimensional cubic nonlinear Schrdinger equation can be recovered by means of some suitable selections ofthe arbitrary functions and arbitrary *** computer simulation,the properties of new non-travelling waveand coefficient function's soliton-like solutions,and elliptic solutions are demonstrated by some plots.

关键词： (2+1)-d cubic nonlinear Schrdinger equation soliton solution elliptic function soltuions

A NEW GENERALIZED ASYNCHRONOUS PARALLELMULTISPLITTING ITERATION METHOD

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Journal of Computational Mathematics 1999年第5期17卷 449-456页

作者： Zhong-zhi Bai(State key laboratory of Scientific and Engineering Computing, ICMSEC, chinese Academyof sciences, {4. 100080, china) 中科院计算数学与科学工程计算所科学与工程计算国家重点实验室北京

For the large sparse systems of linear and nonlinear equations, a new class of generalized asynchronous parallel multisplitting iterative method is presented, and its convergence theory is established under suitable conditions. This method not only unifies the discussions of various existing asynchronous multisplitting iterations, but also affords new algorithmic and theoretical results for the parallel solution of large sparse system of linear equations. Besides its generality, this method is also much more suitable for implementing on the MIMD multiprocessor systems.

关键词： systems of linear and nonlinear equations asynchronous multisplitting iteration relaxed method convergence theory

Optimization of mathematical models for thematic maps

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Science china(Technological sciences) 2010年第S1期53卷 15-24页

作者： QI QingWen1,ZHANG An1,JIANG LiLi1,ZOU XiuPing2,XU Li3 & CHENG Xi1,4.1 institute of Geographical sciences and Natural Resources Research,chinese Academy of sciences,{4. 100101,china 2 institute of Policy and Management,chinese Academy of sciences,{4. 100080,china 3 Taishan University,Taian 271021,china 4.Graduate University of chinese Academy of sciences,{4. 10004.,china institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China institute of Policy and Management Chinese Academy of Sciences Beijing China Taishan University Taian China Graduate University of chinese Academy of sciences Beijing China

The thematic map is a major class of maps designed to demonstrate particular features or concepts,functioning as an indispensable tool in geographical *** process of thematic mapping is one into which geographical research goes deeply and *** key activity and course of thematic map production is the use of mathematical models to create thematic data ***,the selection and optimization of mathematical models is in the forefront of thematic map *** theoretical foundations,mechanisms and methods of mathematical model optimization are expounded in this paper,including two approaches,the phase by phase mode and the multi-aim scheme balance *** studies in eco-environment mapping and emergency mapping are described and analyzed,with a hierarchical analysis method being used in the model optimization for eco-environment fragility and sensitivity assessment mapping in Beibuwan (Guangxi) District,the dynamic system (DS) method being used in the model optimization for ecological security adjustment mapping in Xishuang Banna,Yunnan province,and the multi-phase mode being used in the models for forest fire and infectious diseases mapping.

关键词： thematic map mathematic model optimization

Non-Gaussianity of Racetrack Inflation Models

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Communications in theoretical physics 2007年第7期48卷 189-192页

作者： SUN Cheng-Yit ZHANG De-Hai Department of physics,The Graduate School of The chinese Academy of sciences,beijing 10004.,{4. Department of physics The Graduate School of The Chinese Academy of Sciences Beijing 100049 China

In this paper,we use the result in[*** and ***,arXiv:astro-ph/0510709]to calculate thenon-Gaussianity of the racetrack models in[***-Pillado,et al.,JHEP 04.1(2004.063;arXiv:hep-th/04.6230]and[***-Pillado,et al.,arXiv:hep-th/0603129].The two models give different *** of themare ***,we find that,for multi-field inflationary models with the non-trivial metric of the field space,the condition of the slow-roll cannot guarantee small non-Gaussianities.

关键词： non-Gaussianity non-linear parameter racetrack inflation

Mechanisms of the pancake vortex and vortex line movement in the high T_c superconductors Bi_2Sr_2CaCu_2O_8+δ and La_(1.93)Sr0.0_7CuO_4.δ

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Science china(physics,Mechanics & Astronomy) 2007年第2期50卷 240-248页

作者： WANG WeiXian1,ZHOU Fang2,TAN Shun1,WU Huan1 & ZHANG YuHeng1 1 National High Magnetic Field laboratory,University of Science and Technology of china,Hefei 230026,china 2 National laboratory for Superconductivity,lnstitute of {4. and the Center for Condensed Matter {4.,chinese Academy of sciences,beijing 100080,china National High Magnetic Field laboratory University of Science and Technology of China Hefei China National laboratory for Superconductivity Institute of Physics and the Center for Condensed Matter Physics Chinese Academy of Sciences Beijing China

In the strict sense, it is not very clear why with magnetic field increasing, the normal-superconductive (NS) transition becomes broad for Bi2Sr2CaCu208+δ(Bi2212) while the NS transitions are almost parallel for La193Sroo7Cu04.δ(La214.. In this paper, R-T relations are measured by the six-probe method. We propose a moving mechanism of the pancake vortex and vortex line for Bi2212. The theoretical curves fit the experiment data well.

关键词： superconductivity superconductive pancake vortex dynamics

Preconditioners for higher order edge finite element discretizations of Maxwell's equations

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Science china Mathematics 2008年第8期51卷 1537-1548页

作者： ZHONG LiuQiang1,2,SHU Shi1,2,SUN DuDu3&TAN Lin4.1School of Mathematical and Computational sciences,Xiangtan University,Xiangtan 4.1105,china 2Hunan key laboratory for Computation and Simulation in Science and Engineering,Xiangtan 4.1105,china 3institute of Computational Mathematics and Scientific/Engineering Computing,Academy of Mathematicsand Systems Science,Graduate University of chinese Academy of sciences,chinese Academy sciences,P.O.Box 2719,beijing 100190,china 4.epartment of Math-physics,Nanhua University,Hengyang 4.1001,china School of Mathematical and Computational sciences Xiangtan University Xiangtan China Hunan key laboratory for Computation and Simulation in Science and Engineering Xiangtan China institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Graduate University of Chinese Academy of Sciences Chinese Academy Sciences Beijing China Department of Math-physics Nanhua University Hengyang China

In this paper,we are concerned with the fast solvers for higher order edge finite element discretizations of Maxwell's *** present the preconditioners for the first family and second family of higher order N′ed′elec element equations,*** combining the stable decompositions of two kinds of edge finite element spaces with the abstract theory of auxiliary space preconditioning,we prove that the corresponding condition numbers of our preconditioners are uniformly bounded on quasi-uniform *** also present some numerical experiments to demonstrate the theoretical results.

关键词： preconditioner higher order edge finite element stable decomposition

Sediment transport capacity of hyperconcentrated flow

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Science china(physics,Mechanics & Astronomy) 2008年第8期51卷 961-975页

作者： SHU AnPing1,2 & FEI XiangJun2 1 School of Environment & key laboratory of Water and Sediment sciences,Ministry of Education,beijing Normal University,beijing 100875,china 2 State key laboratory of Hydroscience and Engineering,Tsinghua University,beijing 100084.china School of Environment & key laboratory of Water and Sediment sciences Ministry of Education Beijing Normal University Beijing China State key laboratory of Hydroscience and Engineering Tsinghua University Beijing China

As one of the most important components of river mechanics,sediment transport capacity of sediment-laden flows has attracted much attention from many researchers working on river mechanics and hydraulic engineering. Based on the time-averaged equation for a turbulent energy equilibrium in solid and liquid two-phase flow,an expression for the efficiency coefficient of suspended load movement was derived for the two-dimensional,steady,uniform,fully-developed turbulent flow. A new structural expression of sediment transport capacity was achieved. Using 115 runs of flume experimental data,which were obtained through two kinds of sediment transport experiments in the state of equilibrium,in combination with the basic rheological and sediment transporting characteristics of hyperconcentrated flow,the main parameters in the structural expression of sediment transport capacity were calibrated,and a new formula of sediment transport capacity for hyperconcentrated flow was developed. A large amount of field data from the Yellow River,Wuding River,and Yangtze River,etc. were adopted to verify the new formula and good agreement was obtained. These results above contribute to an improved theoretical system of river mechanics and a reliable tool for management of rivers carrying high concentration of sediments.

关键词： hyperconcentrated flow turbulent energy equilibrium efficiency coefficient sediment transport capacity