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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 100871 China school of physics Peking University Beijing 100871 China BNLMS State Key Laboratory for Structural Chemistry of Unstable and Stable Species College of Chemistry and Molecular Engineering Peking University Beijing 100871 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

The low-lying rotational bands of the neutron-rich nucleus ^(172)Tm

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Science china(physics,Mechanics & Astronomy) 2009年第10期52卷 1542-1547页

作者： CHEN BaoRen1,LI Tao1 & LIU ShuXin1,2 1 school of physics,peking university,beijing 100871,china 2 Center of Theoretical Nuclear physics,National Laboratory of Heavy Ion Collisions,Lanzhou 730000,china school of physics Peking University Beijing China Center of Theoretical Nuclear physics National Laboratory of Heavy Ion Collisions Lanzhou China

The microscopic mechanism of four experimentally observed bands in 172Tm is investigated using the particle-number conserving method of the cranked shell model with monopole and quadrupole paring *** experimental results,including the moments of inertia and angular momentum alignments of four bands in 172Tm are reproduced well by the particle-number conserving *** ω variation of the occupation probability of each cranked orbital and the contribution to moment of inertia from each cranked orbital are *** unobserved low-lying bands of 2-quansiparticles in 172Tm are predicted.

关键词： neutron-rich nucleus rare earth rotational band

A Method of Calculating Ice Water Content Using Data of Two Dimensional Cloud Particle Images from PMS

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A Method of Calculating Ice Water Content Using Data of Two ...

Hierarchical structures in climate and atmospheric turbulence

中国气象学会2004年年会

作者： Shen Ning~1 Xin Huolin~2 Zhao Chunsheng~1 Zhao Zengliang~1 (1 Department of Atmospheric Science, school of physics, peking university, beijing 100871, china 2 Department of physics, school of physics, peking university, beijing 100871, china)

＜正＞An inverse calculation of ice water content （IWC） of clouds from PMS two dimensional cloud images is described in this paper. This study provides an algorithm to refine the observed aspect ratios of different shape categories. Expectation of 2-D cloud particles’ pro ected area and that of the IWC are calculated with respect to various particle shapes and different size distributions. It is shown that the formula of inverse calculation from assembly average of 2-D cloud images to the mean IWC of cloud particles is obtainable;and the aspect ratios of different shape categories could be *** of spherical approximation are also studied quantitatively.

关键词： IWC PMS cloud particle projected area

来源： cnki会议评论

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Progress in Natural Science:Materials International 2002年第10期 29-34页

作者： SHE Zhensu, FU Zuntao, CHEN Jiong, LIANG Shuang and LIU Shida(1. State Key Laboratory for Studies of Turbulence and Complex Systems, Department of Mechanics and Engineering Sciences, peking university, beijing 100871, china 2. school of physics, peking university, beijing 100871, china 3. LAPC, Institute of Atmospheric physics, Chinese Academy of Sciences, beijing 100029, china) State Key Laboratory for Studies of Turbulence and Complex Systems，Department of Mechanics and Engineering Sciences，peking university，beijing 100871，china LAPC，Institute of Atmospheric physics，Chinese Academy of Sciences，beijing 100029，china school of physics，peking university，beijing 100871，china State Key Laboratory for Studies of Turbulence and Complex Systems，Department of Mechanics and Engineering Sciences，peking university，beijing 100871，china school of physics，peking university，beijing 100871，china

The climatic time series encompass many time scales, forming multi-scale climatic variations and hierarchies. The periods and magnitudes of cooling or warming, especially for extreme climatic events, vary with the time scales. On the other hand, high-frequency atmospheric turbulent motions, which are certainly related to the climatic changes, are also typical multi-scale phenomena. In this paper, certain properties of the fluctuations are examined that are invariant with the change of the time scales. Specifically, the existence of a statistical similarity law is demonstrated in climatic time series and in atmospheric turbulent motions. This is the hierarchical similarity law. Further analyses show that the hierarchical similarity law is a general property of multi-scale fluctuation systems. Therefore, the study on the hierarchical similarity law is important for understanding the inherent universal physical mechanism of complex systems in the atmospheric motions.

关键词： climate multi-scale hierarchical structure atmospheric turbulence.

INFINITE ELEMENT METHOD FOR THE EXTERIOR PROBLEMS OF THE HELMHOLTZ EQUATIONS

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Journal of Computational Mathematics 2000年第6期18卷 657-672页

作者： Lung-an Ying (school of Mathematical Sciences, peking university, beijing 100871, china) 北京大学北京 100871

There are two cases of the exterior problems of the Helmholtz equation. If λ ≥ 0 the bilinear form is coercive, and if λ < 0 it is the scattering problem. We give a new approach of the infinite element method, which enables us to solve these exterior problems as well as corner problems. A numerical example of the scattering problem is given. [ABSTRACT FROM AUTHOR]

关键词： Helmholtz equation exterior problem infinite element method

Abrupt climate change and collapse of ancient civilizations at 2200BC-2000BC

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Progress in Natural Science:Materials International 2005年第10期15卷 46-52页

作者： WANG Shaowu (Department of Atmospheric Science, school of physics, peking university, beijing 100871, china) Department of Atmospheric Science School of Physics Peking University Beijing 100871 China

Plentiful evidence of historical, archaeological and palaeoclimatic studies proved that an abrupt change from wetter to drier climate occurred over the Nile Valley,the Mesopotamia, the Indus Valley and Huanghe River Valley at 2200BC-2000BC. The abrupt change was developed based on the general lowering of temperature in the middle latitudes, and was a strong cold event since the beginning of the Megathermal (8.5-3.0 kaBP). Collapse of Nile civilization appeared at the First Intermediate Period (2181BC-2040BC). Civilization of Mesopotamia began collapse following the disintegration of Akkadian Empire. This process lasted to the foundation of Babylon Kingdom from 2200BC to 1900BC. Indus civilization abruptly fell off at 1800BC. A widespread alternation of archaeological cultures happened in china at ca. 2000BC except only in its central part. Longsheng culture was replaced by the Erlitou culture, which is now acknowledged in china as Xia Culture. Foundation of Xia Dynasty at 2070BC opened a new chapter in the development of Chinese civilization. Studies indicated that abrupt climate change may be caused by the weakening of the Thermohaline Circulation (THC).

关键词： 2200BC-2000BC abrupt climate change collapse of ancient civilization.

|m| Partial wave treatment for two-dimensional Coulomb-scattering and Regge pole

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Science china(physics,Mechanics & Astronomy) 2004年第6期47卷 676-684页

作者： WANG Jing & ZENG Jinyan Department of physics,Tsinghua university,beijing 100084,china school of physics,peking university,beijing 100871,china Department of physics Tsinghua University Beijing 100084 China school of physics Peking University Beijing 100871 China

The symmetry and |m| partial-wave analysis for two-dimensional (2D) Coulomb-scattering is investigated. As a function of energyE, the |m| partial-wave scattering amplitudef |m|(θ) is analytically continuated to the, negativeE (complexk) plane, and it is found that the bound state energy eigenvalues (E<0) are just located at the poles off |m|(θ) on the positive imaginaryk axis as is expected. In addition, as a function of |m|,f |m|(θ) is analytically continuated to the complex |m| plane, the bound state energy eigenvalues are just located at the poles off |m|(θ) on the positive real |m| axis.

关键词： two-dimensional Coulomb scattering, |m| partial-wave, Regge pole.

REGULARITY OF SOLUTIONS TO THE DIRICHLET PROBLEM FOR DEGENERATE ELLIPTIC EQUATION

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Chinese Annals of Mathematics,Series B 2003年第4期24卷 529-540页

作者： CHEN YEMIN school of Mathematics, peking university, beijing 100871, china. school of Mathematics Peking University Beijing 100871

In this paper, the author studies the regularity of solutions to the Dirichlet problem forequation Lu = f, where L is a second order degenerate elliptic operator in divergence form inΩ, a bounded open subset of Rn (n... 详细信息

关键词： Regularity Dirichlet problem Degenerate Weighted spaces

THE PHYSICAL ENTROPY OF SINGLE CONSERVATION LAWS

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Journal of Computational Mathematics 1998年第5期16卷 437-444页

作者： (Department of Mathematics, peking university, beijing 100871, china) 北京大学数学系北京

By means of the comparisons with the formulas in statistical mechanics and thermodynamics, in this paper it is demonstrated that for the single conservation law partial derivative(t)u + partial derivative(x)f(u) = 0, if the flux function f(u) is convex (or concave), then, the physical entropy is S = -f(u); Furthermore, if we assume this result can be generalized to any f(u) with two order continuous derivative, from the thermodynamical principle that the local entropy production must be non-negative, one entropy inequality is derived, by which the O.A. Olejnik's famous E- condition can be explained successfully in physics.

关键词： conservation laws entropy entropy production