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Il-8-induced l-selectin shedding regulates its binding kinetics to PSGl-1

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chinese Science Bulletin 2009年第16期54卷 2786-2793页

作者： JIA Xiaoling1,2,3, CHEN Juan1,2 & lONG Mian1,2 1 National Microgravity laboratory, institute of Mechanics, chinese academy of sciences, beijing 100190, china 2 Center of Biomechanics and Bioengineering, institute of Mechanics, chinese academy of sciences, beijing 100190, china 3 School of Biological Science and Medical Engineering, Beihang University, beijing 100083, china National Microgravity laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China Center of Biomechanics and Bioengineering Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China School of Biological Science and Medical Engineering Beihang University Beijing 100083 China

l-selectin plays a crucial role in inflammation cascade by initiating the tethering and rolling of leukocytes on endothelium wall. While many l-selectin molecules are rapidly shed from the cell surface upon activation, the remaining membrane-anchored l-selectin may still play an important role in regulating leukocyte rolling and adhesion with different binding kinetics. Here we developed an in vitro model to activate Jurkat cells via interlukin-8 (Il-8) and quantified the two-dimensional (2D) binding kinetics, using a micropipette aspiration assay, of membrane-anchored l-selectin to P-selectin glycoprotein ligand 1 (PSGl-1) ligand coupled onto human red blood cells (RBCs). The data indicated that l-selectin shedding reduced the amount of membrane-anchored l-selectin and lowered both its reverse and forward rates. These results suggested that the rolling dynamics of activated leukocytes was determined by two opposite impacts: reducing the surface presentation would enhance the rolling but lowering the kinetic rates would decrease the rolling. This finding provides a new insight into under-standing how l-selectin shedding regulates leukocyte rolling and adhesion.

关键词：结合动力学选择素配体白细胞介素8 Jurkat细胞诱导细胞表面微管吸吮

Formal Verification under Unknown Constraints

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Wuhan University Journal of Natural sciences 2005年第1期10卷 43-46页

作者： lI Guang-hui 1,2,3 , lI Xiao-wei 2,31. School of Information Engineering, Zhejiang Forestry college, Hangzhou 311300, Zhejiang, china 2. institute of Computing Technology, chinese academy of sciences, beijing 100080, china 3. Graduate School of the chinese academy of sciences, beijing 100039, china School of Information Engineering Zhejiang Forestry College Hangzhou 311300 Zhejiang China

We present a formal method of verifying designs with unknown constraints (e.g., black boxes) using Boolean satisfiability (SAT). This method is based on a new encoding scheme of unknown constraints, and solves the corresponding conjunctive normal form (CNF) ***,this method can avoid the potential memory explosion, which the binary decision diagram (BDD) based techniques maybe suffer from, thus it has the capacity of verifying large designs. Experimental results demonstrate the efficiency and feasibility of the proposed method.

关键词： formal verification unknown constraints black box Boolean satisfiability Boolean comparison

lactariolide,a New 14-Membered-Ring Compound from lactarius Subvellereus

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chinese Chemical letters 1997年第2期8卷 135-136页

作者： Jing ZHANG Xiao Zhang FENG(institute of Materia Medica, chinese academy of Medical sciences and peking union Medical college, beijing, 100050) chinese ACAD MED SCI INST MAT MEDBEIJING 100050PEOPLES R CHINA beijing union MED COll BEIJING 100050PEOPLES R CHINA

lactariolide (I), a new 14-membered-ring lactone was isolated from the fruit bodies of lactarius subvellereus (Russulaceae), and its structure was elucidated as (R)-13-hydroxy-trans-9, 11-octadecadienoic acid lactone ... 详细信息

关键词： Cl lactariolide,a New 14-Membered-Ring Compound from lactarius Subvellereus

Crustal structure of Gondwana-and Yangtze-typed blocks:An example by wide-angle seismic profile from Menglian to Malong in western Yunnan

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Science china Earth sciences 2005年第11期48卷 1828-1836页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2, TENG Jiwen1, lü Qingtian3, lI Jiliang1, SUN Shanxue1 & WANG Xinzheng1 1. institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 2. institute of Geophysics, chinese Seismological Bureau, beijing 100081, china 3. institute of Deposition Resource, chinese academy of Geological sciences, beijing 100037, china 1. institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. institute of Geophysics Chinese Seismological Bureau 100081 Beijing China 3. institute of Deposition Resource Chinese Academy of Geological Sciences 100037 Beijing China

The wide-angle seismic profile between Menglian and Malong crosses the Baoshan block (Gondwana-typed), and Simao and southwestern Yangtze blocks (Yangtze-typed). By in-terpreting the wide-angle seismic data, we obtained the seismic crust/upper mantle structure of P-wave velocities together with the seismic reflections of these three blocks, Changning- Menglian and Mojiang suture zones among the mentioned three blocks. Our interpreting results demonstrate that the P-wave crustal velocity of Simao block is slower than that of Baoshan and southwestern Yangtze block and the crustal thickness gradually thickens from the Baoshan block, Simao to southwestern Yangtze block. Crustal reflection patterns of these three blocks have dis-tinct differences too. For the Gondwana-typed blocks, seismic reflections in the upper crust are well developed while in middle-lower crust they are very weak. The crustal reflections in the Yangtze block are very well developed. The crustal reflection patterns in Simao and southwest-ern Yangtze blocks are distinguishable. The average thickness of the crust in the studied area is about 40 km. And we make some discussions on the crustal thickening model of the three blocks in western Yunnan and tectonic setting of seismic developing and interaction of Gondwana and Yangtze blocks.

关键词： Gondwana blocks,Yangtze blocks,wide-angle profile,crustal structure,tectonic setting

Effects of Aging and Advanced Glycation on Gene Expression in Cerebrum and Spleen of Mice

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Biomedical and Environmental sciences 2003年第4期16卷 323-332页

作者： YUE-XIN lIANG, ZHEN WANG, DIAN-DONG lI, JIAN-MIN JIANG,AND RONG-GUANG SHAOinstitute of medicinal Biotechnology, chinese academy of Medical sciences and peking union Medical college, beijing 100050, china institute of medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College Beijing 100050 China

Objective To analyze the effects of aging or advanced glycation on gene expression in the cerebrum and spleen of female C57Bl/6J mice. Methods The gene expression profile was determined by using cDNA expression arrays containing 588 cDNA. Results Aging and advanced glycation resulted in differential gene expression patterns of cerebrum and spleen compared with young mice. Among the 80 genes detected in cerebrum, 43 exhibited a change in mRNA ratios with aging or treatment. Thirty-four changes (79%) were common in aged and D-galactose treated mice, whereas the cerebrum from aged and AGE-lysine treated mice showed common changes in expression of 38 genes (88%). Of the 86 genes detected in spleen, 29 (34%) displayed an age-related decrease in expression, whereas 3 (3%) displayed an increase in expression levels with aging. Eighteen genes from the detectable genes exhibited expression changes in both cerebrum and spleen of mice. Conclusions The gene expression profiles of D-galactose and AGE-lysine treated mice resemble those of aged mice. Use of cDNA hybridization arrays may provide a promising tool to explore the mechanism of aging at a molecular level.

关键词： Aging Galactose Advanced glycation Gene expression DNA microarrays Cerebrum Spleen

The gravitational gradient tensor’s invariants and the related boundary conditions

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Science china Earth sciences 2010年第5期53卷 781-790页

作者： YU JinHai1,2,3 & ZHAO DongMing4 1 college of Earth Science, Graduate University of chinese academy of sciences, beijing 100049, china 2 institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 430077, china 3 State Key laboratory of Astronautic Dynamics, Xi’an 710043, china 4 Zhengzhou institute of Surveying and Mapping, Zhengzhou 450052, china 1. college of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Institute of Geodesy and Geophysics Chinese Academy of Sciences Wuhan 430077 China3. State Key Laboratory of Astronautic Dynamics Xi’an 710043 China4. Zhengzhou Institute of Surveying and Mapping Zhengzhou 450052 China

Here we report new approaches of recovering the Earth gravitational field from GOCE (Gravity field and steady-state Ocean Circulation Explorer) gradiometric data with the help of the gradient tensor’s invariants. Our results only depend on GOCE satellite’s position and gradiometry, in other words, they are completely independent of the satellite attitude. First, starting from the invariants, linearization models are established, which can be referred as the general boundary conditions on the satellite’s orbit. Then, the spherical approximation expressions for the models are derived, and the corresponding solving methods for them are discussed. Furthermore, considering effects of J2-term, the spherical approximation models are improved so that the accuracies of the boundary conditions can be theoretically raised to O ( J 2/2 T), which is approximately equivalent to O(T2). Finally, some arithmetic examples are constructed from EGM96 model based on the derived theories, and the computational results illustrate that the spherical models have accuracies of 10-7 and the order recovering the gravitational field can reach up to 200, and the models with regard to effect of J2-term have accuracies of 10-8 and the order can reach up to 280.

关键词： the Earth’s gravitational field gravitational gravidiometry tensor’s invariant

Formation of super-concentrated hydrochloric acid in the third phase in tertiary amine N235-PtCl_6^(2-)-HCl system and its influences on the Pt microemulsion extraction

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Science china Chemistry 2009年第11期52卷 1825-1834页

作者： HUANG Kun1,CHEN Jing1,ZHANG ChengFeng1,2.lI ZhiHong3,PAN QingHua1,SUN Yan1,lIU ShaoXuan1,lIU XueXin2.lI WeiHong1,YANG Zhanlan1,WENG ShiFu1,HU TianDou3,XU YiZhuang1 & WU JinGuang1 1 college of Chemistry and Molecular Engineering,peking University,beijing 100871,china 2 institute of Chemistry,chinese academy of sciences,beijing 100190,china 3 institute of High Energy Physics,chinese academy of sciences,beijing 100049,china 1. college of Chemistry and Molecular Engineering Peking University Beijing 100871 China 2. institute of Chemistry Chinese Academy of Sciences Beijing 100190 China 3. institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China

In this paper,we have investigated the formation of the third-phase in tertiary amine(N235)-PtCl62--HCl system and the microscopic phase structural evolution of platinum-loaded organic phases before and after the occurrence of the *** third-phase is characterized by various spectroscopic techniques,and the small angle X-ray scattering(SAXS) experiments demonstrate the appearance of nano-aggregates,i.e.,water-in-oil reversed micelles,in the third *** experimental results indicate that(1) formation of the third phase is related to the aggregation behaviors of nano-reversed micelles in which a super-concentrated hydrochloric acid formed with the H+ to H2O molar ratio being much higher than that of the conventional 37 wt% saturated hydrochloric acid.(2) The occurrence of the super-concentrated HCl results in a great amount of H+ and Cl-ions enriched and confined within the nano-water pools of W/O reversed micelles in third ***,the coordination behaviors of platinum complex ions in that super-concentrated hydrochloric acid are very different from their corresponding behaviors in bulk aqueous *** is possible that H+ ions participate in the formation of such complexes as HmPtCl6z+ in the super-concentrated hydrochloric acid.(3) The relative contents of various HmPtCl6z+ complexes are different corresponding to the H+ ion concentrations in confined nanowater *** association ability of the acidified tertiary amine N235 molecules(R3NH+) with various HmPtCl6z+ complexes plays an important role in affecting the platinum extraction behaviors.

关键词： solvent extraction third phase super-concentrated hydrochloric acid tertiary amine platinum

Bursting of Morris-lecar neuronal model with current-feedback control

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Science china(Technological sciences) 2009年第3期52卷 771-781页

作者： DUAN liXia1, lU QiShao2 & CHENG DaiZhan3 1 college of Science, North china University of Technology, beijing 100144, china 2 School of Science, beijing University of Aeronautics and Astronautics, beijing 100191, china 3 institute of Systems Science, chinese academy of sciences, beijing 100190, china college of Science North China University of Technology Beijing 100144 China School of Science Beijing University of Aeronautics and Astronautics Beijing 100191 China institute of Systems Science Chinese Academy of Sciences Beijing 100190 China

The Morris-lecar (Ml) neuronal model with current-feedback control is considered as a typical fast-slow dynamical system to study the combined influences of the reversal potential VCa of Ca2+ and the feedback current I on the generation and transition of different bursting oscillations. Two-parameter bifurcation analysis of the fast subsystem is performed in the parameter (I, VCa)-plane at first. Three important codimension-2 bifurcation points and some codimension-1 bifurcation curves are obtained which enable one to determine the parameter regions for different types of bursting. Next, we further divide the control parameter (V0, VCa)-plane into five different bursting regions, namely, the "fold/fold" bursting region R1, the "fold/Hopf" bursting region R2, the "fold/homoclinic" bursting region R3, the "subHopf/homoclinic" bursting region R4 and the "subHopf/subHopf" bursting region R5, as well as a silence region R6. Codimension-1 and -2 bifurcations are responsible for explanation of transition mechanisms between different types of bursting. The results are instructive for further understanding the dynamical behavior and mechanisms of complex firing activities and information processing in biological nervous systems.

关键词： neuron bursting bifurcation fast-slow dynamics analysis codimension

SiO/CNTs:A new anode composition for lithium-ion battery

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Science china Chemistry 2009年第12期52卷 2047-2050页

作者： REN YuRong1,2,3?,QU MeiZhen1 & YU Zuolong1 1 Chengdu institute of Organic Chemistry,chinese academy of sciences,Chengdu 610041,china 2 college of Chemistry,Jilin Normal University,Siping 136000,china 3 Graduate University of chinese academy of sciences,beijing 100039,china 1. Chengdu institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 China 2. college of Chemistry Jilin Normal University Siping 136000 China 3. Graduate University of chinese academy of sciences Beijing 100039 China

A new anode composition SiO/CNTs (carbon nanotubes) has been prepared by chemical vapor deposition (CVD) method. The results of scanning electron microscopy (SEM) confirm that CNTs deposit on small SiO particles,form a cage,and enwrap SiO particles tightly. SiO/CNTs anode composition exhibits an initial discharge and charge capacity of 1171 and 789 mAh/g,and maintains a reversible capacity of 500 mAh/g after 80 cycles. The improvement of the cyclic performance for SiO/CNTs composition is related to the maintaining of the electric network during cycling,which benefits from a tight contact between CNTs and SiO particles.

关键词： SiO/CNTs CVD composition anode li-ion battery