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Synthesis and Crystallization of N-Benzoyl Tauryl Phenylalanine

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Chinese Chemical Letters 1997年第9期8卷 779-780页

作者： Ya Li KONG Sheng JIN(department of Chemistry, peking university,{2. 100871) beijing UNIV DEPT CHEMBEIJING 100871PEOPLES R CHINA

The substrate hippuryl phenylalanine of carboxypeptidase A was selected as model to design new hapten molecule. N-Benzoyl tauryl phenylalanine (I) was synthesized and its structure was characterized by X-ray crystallo... 详细信息

关键词： KBr IR cm THF FAB DMSO 亚砜 Synthesis and Crystallization of N-Benzoyl Tauryl Phenylalanine

Up-regulation of Cartilage Oligomeric Matrix Protein Gene Expression by Insulin-like Growth Factor-Ⅰ Revealed by Real Time Reverse Transcription-Polymerase Chain Reaction

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Acta Biochimica et Biophysica Sinica 2006年第10期38卷 677-682页

作者： Hua TIAN~(1,2.) Ioannis STOGIANNIDIS~2. 1 department of Orthopaedics,peking {2. Third Hospital,beijing 100083,China 2.Coxa Hospital for Joint Replacement,Biokatu 6 b,Tampere 33101,Finland department of Orthopaedics Peking University Third HospitalBeijing 100083 China Coxa Hospital for Joint Replacement Biokatu 6 bTampere 33101 Finland

Cartilage oligomeric matrix protein (COMP) strengthens cartilage by binding to type Ⅱ and typeⅨ collagen-forming bridges between collagen *** was hypothesized that perhaps one or more anabolicgrowth factors such as insulin-like growth factor-Ⅰ (IGF-Ⅰ),fibroblast growth factor-1 (FGF-1) or plateletderived growth factor-BB (PDGF-BB) increase COMP gene *** effects on primary humanchondrocytes and the chondrogenic cell line ATDC5 were studied using real time reverse transcript-poly-merase chain reaction (RT-PCR) for ***-Ⅰ,but not the FGF-1 or PDGF-BB,up-regulatedCOMP gene expression by approximate 5-fold in human adult chondrocytes in a dose-and ***-Ⅰ exerted similar effects on ATDC5 *** from these real time RT-PCR experimentswere confirmed by transfecting into ATDC5 cells a full-length mouse COMP promoter cloned upstream of aluciferase reporter *** stimulation with IGF-Ⅰ,the luciferase reporter activity increased by about *** conclusion,IGF-Ⅰ seems to be an important positive regulator of COMP,which may play animportant role in an attempted repair of either traumatized or degenerated cartilage.

关键词： cartilage oligomeric matrix protein (COMP) insulin-like growth factor-Ⅰ(IGF-Ⅰ) gene expression

A computer code for beam optics calculation--third order approximation

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Progress in Natural Science:Materials International 2006年第6期16卷 667-670页

作者： Lü Jianqin and LI Jinhai (Institute of Heavy Ion physics, peking university,{2. 100871, China) [a]Institure of Heavy Ion physics Peking University Beijing China

To calculate the beam transport in the ion optical systems accurately, a beam dynamics computer program of third order approximation is developed. Many conventional optical elements are incorporated in the program. Particle distributions of uniform type or Gaussian type in the (x, y, z) 3D ellipses can be selected by the users. The optimization procedures are provided to make the calculations reasonable and fast. The calculated results can be graphically displayed on the computer monitor.

关键词： beam transport computer program third order approximation Lie algebra.

Pairwise entanglement and local polarization of Heisenberg model

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Science China(physics,Mechanics & Astronomy) 2008年第10期51卷 1515-1522页

作者： XI XiaoQiang1,2. ZHANG Tao3, YUE RuiHong3,4 & LIU WuMing2.1 department of Applied Mathematics and physics, Xi’an Institute of Post and Telecommunications, Xi’an 710061, China 2.2. National Laboratory for Condensed Matter physics, Institute of physics, Chinese Academy of Sciences,{2. 100080, China 3 Institute of Modern physics, Northwest university, Xi’an 710069, China 4 department of physics, Ningbo university, Ningbo 3152.1, China department of Applied Mathematics and physics Xi’an Institute of Post and Telecommunications Xi’an 710061 China beijing National Laboratory for Condensed Matter physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China Institute of Modern physics Northwest University Xi’an 710069 China department of physics Ningbo University Ningbo 315211 China

The characteristics of pairwise entanglement and local polarization (LP) are dis-cussed by studying the ground state (states) of the Heisenberg XX model. The re-sults show that: the ground state (states) is (are) composed of the micro states with the minimal polarization (0 for even qubit and 1/2.for odd qubit); LP and the prob-ability of the micro state have an intimate relation, i.e. the stronger the LP, the smaller the probability, and the same LP corresponds to the same probability; the pairwise entanglement of the ground state is the biggest in all eigenvectors. It is found that the pairwise entanglement is decreased by the state degeneracy and the system size. The concurrence approaches a fixed value of about 0.3412.(for odd-qubit chain) or 0.3491 (for even-qubit chain) if the qubit number is large enough.

关键词： Heisenberg XX model local polarization pairwise entanglement

Lookback time as a test for f(R) gravity in the Palatini approach

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Research in Astronomy and Astrophysics 2011年第11期11卷 1257-1265页

作者： Zhong-Xu Zhai and Wen-Biao Liu department of physics, Institute of Theoretical physics,{2. Normal university,{2. 100875, China department of physics Institute of Theoretical Physics Beijing Normal University Beijing 100875 China

We use the recently released data of lookback time (LT)-redshift relation, the cosmic microwave background shift parameter and the baryon acoustic oscillation measurements to constrain cosmological parameters of f (R) gravity in the Palatini formalism by considering the f (R) form of type (a) f (R) = R β/Rn and (b) f (R) = R + α ln R β. Under the assumption of a Friedmann-Robertson-Walker universe, we achieved the best fitting results of the free parameters (Ωm0, n) for (a) and (Ωm0, α) for (b). We find that current LT data can provide interesting and effective constraints on gravity models. Compared with other data, the LT constraints favor a smaller value of the non-relativistic matter energy density.

关键词： cosmology cosmic microwave background

Metallogenic characteristics of epithermal gold deposits in China

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Chinese Science Bulletin 1999年第S2期44卷 136-138页

作者： FENG Jianzhong~1 and WANG Jingbin~2.1. department of Geology, peking university,{2. 100871, China 2.{2. Institute of Geology For Mineral Resources,{2. 100012. China department of Geology Peking University Beijing 100871 China beijing Institute of Geology for Mineral Resources Beijing 100012 China

VOLCANIC-SUBVOLCANIC rocks are extensively distributed in China, in which a series of epithermal golddeposits related to volcanism have been discovered. 1 Metallogenic tectonic settings of epithermal gold deposits The epithermal gold deposits are mainly formed under the following tectonic settings: (i) ancient island arc collision, such as Xingxingxia island arc, Armantai island arc, Beishan island arc and Jueluotage island arc, etc. in periphery of Gunggar, Altai, Baishan, etc. in ancient Europe domain; (ii) extension area of continental margin of back arc, such as Fujian, Zhejiang, Jiangsu and Henlongjiang, *** circum-Pacific metallogenic domain; (iii) Mesozoic-Cenozoic island arc, such as the Tethys-Himalayametallogenic domain and Taiwan; (iV) intracontinental faulting depression or intraplate deep-seatedfaults, such as northern Hebei, Liaoning, Inner Mongolia at the north margin of the North China platformand periphery of Taicheng-Loujiang fault.

关键词： metallogenic characteristics gold deposits China.

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 {2., 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

Hawking radiation and thermodynamics of a Vaidya-Bonner black hole

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Research in Astronomy and Astrophysics 2010年第1期10卷 33-38页

作者： Zhen-Feng Niu Wen-Biao Liu department of physics Hebei North University Zhangjiakou 075000 China department of physics Institute of Theoretical Physics Beijing Normal University Beijing 100875 China

Using Parikh＇s tunneling method, the Hawking radiation on the apparent horizon of a Vaidya-Bonner black hole is calculated. When the back-reaction of particles is neglected, the thermal spectrum can be precisely obtained. Then, the black hole thermodynamics can be calculated successfully on the apparent horizon. When a relativistic perturbation is applied to the apparent horizon, a similar calculation can also lead to a purely thermal spectrum. The first law of thermodynamics can also be derived successfully at the new supersurface near the apparent horizon. When the event horizon is thought of as a deviation from the apparent horizon, the expressions of the characteristic position and temperature are consistent with the previous viewpoint which asserts that the thermodynamics should be based on the event horizon. It is concluded that the thermodynamics should be constructed exactly on the apparent horizon while the event horizon thermodynamics is just one of the perturbations near the apparent horizon.

关键词： black hole physics -- relativity -- kinematics and dynamics

A modified soft docking method for proteins and peptides

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Chinese Chemical Letters 1997年第7期8卷 615-618页

作者： Jun Mei WANG Li Rong CHEN Fan JING Xiao Jie XU(department of chemistry and Weixin Institute of Natural Medicine,peking {2., beijing 100871)(department of Technical physics, peking university, beijing 100871)(department of Biophysics, {2. beijing UNIV DEPT CHEM BEIJING 100871 PEOPLES R CHINA beijing UNIV WEIXIN INST NAT MED BEIJING 100871 PEOPLES R CHINA beijing UNIV DEPT TECH PHYS BEIJING 100871 PEOPLES R CHINA UNIV ROCHESTER DEPT BIOPHYS ROCHESTER NY 14642 USA

A modified two-stage soft-docking procedure was developed for the theoretic researches on the recognition of protein-protein or protein-peptide complexes. Some systems have been used to test our program and the result... 详细信息

关键词： A modified soft docking method for proteins and peptides