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Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central China: Constraints from geochemistry and melt inclusions

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science China Earth sciences 2005年第8期48卷 1146-1157页

作者： SU Li1,2, SONG Shuguang3.& ZHOU Dingwu1 1. Key Laboratory of Continental Dynamics of the Ministry of Education, Department of Geology, Northwestern university, Xi’an 710069, China 2. The Geological Lab center, China university of Geo{3.s (beijing), beijing 100083. China 3. Key Laboratory of Orogenic Belts of the Ministry of Education, Department of Geology, peking university, beijing 100871, China 1. Key Laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University 710069 Xi’an China 2. The Geological Lab center China University of Geosciences 100083 (Beijing)Beijing China 3. Key Laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University 100871 Beijing China

The Songshugou dunite body, which occupies an area of about 20 km2, is the largest ultramafic massif in the eastern Qinling orogenic belt, Central China. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2O3. CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.

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Response synchronization: New progress in brain-visual information processing

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Chinese science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry , Institute of Atmospheric Physics , Chinese Academy of sciences , beijing 100029, China 2. Commission of the National Natural science Foundation of China , beijing 100083. China 3. the center of information science , peking university, beijing 100871, China 4. Open Laboratory of Visual information Processing , Institute of Biophysics , Chinese Academy of sciences , beijing 100101, China State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National Natural science Foundation of China Beijing China The center of information science Peking University Beijing China Open Laboratory of Visual information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. Naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

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Role of inositol 1,4,5-trisphosphate receptors in α1-adrenergic receptorinduced cardiomyocyte hypertrophy

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Acta Pharmacologica Sinica 2006年第7期27卷 895-900页

作者： Da-li LUO~(2,3.5) Jian GAO~2 Xiao-mei LAN~3.Gang WANG~4 Sheng WEI~4 Rui-ping XIAO~4 Qi-de HAN~3. Department of Pharmacology,School of Chemical Biology & Pharmaceutical sciences,Capital university of Medical sciences,{3. 100069,China 3.Institute of Cardiovascular science at Health science center,peking university {3. 100083.China 4 Institute of Molecular Medicine and College of Life science,peking university,{3. 100871,China Department of Pharmacology School of Chemical Biology & Pharmaceutical Sciences Capital University of Medical Sciences Beijing 100069 China Institute of Cardiovascular science at Health science center Peking University Beijing 100083 China Institute of Molecular Medicine and College of Life science Peking University Beijing 100871 China

Aim:Intracellular Ca2+plays pivotal roles in diverse cellular functions,includinggene transcription that underlies cardiac remodeling during stress ***,the role of inositol 1,4,5-trisphosphate receptors（IP3.s）in the media-tion of cardiac intracellular Ca2+and hypertrophic growth remains *** with neonatal rat ventricular myocytes suggests that activation of IP3.smay be linked to α1adrenergic receptor（α1AR）increased stereotyped Ca2+sparkoccurrence and global Ca2+***,we hypothesized that Ca2+releasethrough IP3.s was necessary for α1AR-stimulated cardiac ***:We used myoinositol 1,4,5-trisphosphate hexakis（butyryloxymethyl）ester（IP3.M）,a membrane-permeant ester of IP3.to activate IP3.s directly,and Fluo 4/AM tomeasure intracellular Ca2+***:IP3.M(10μmol·L-1)mimicked theeffects of phenylephrine,a selective agonist of α1AR,in increments in local Ca2+spark release（especially in the perinuclear area）and global Ca2+*** importantly,IP3. inhibitors,2-aminoethoxydiphenyl borateand Xestospongin C,abolished the IP3.M-induced Ca2+responses,and signifi-cantly suppressed α1AR-induced cardiomyocyte hypertrophy assayed by cellsize,[3.]leucine incorporation and atrial natriuretic factor gene expression,dur-ing sustained（48 h）phenylephrine ***:These results,therefore,provide cellular mechanisms that link IP3. signaling to α1AR-stimulatedgene expression and cardiomyocyte hypertrophy.

关键词： inositol 1,4,5-trisphosphate receptors Ca2+sparks α1 adrenergic stimulation cardiac hypertrophy

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A　Diference　Scheme　with　Anti－difusion　Terms　to　Improve　the　Computation　of　Contact　Discontinuities　and　the　Study　of　Weak　Discontinuities　in　Compresible　Flow

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Communications in Nonlinear science and Numerical Simulation 1996年第4期1卷 42-51页

作者： Chunguang XU (College of Mathematical science ,peking university,{3.) College of Mathematical science peking university beijing 100871 USA

Ａｂｓｔｒａｃｔ：ＴｈｅｉｎｖｅｓｔｉｇａｔｉｏｎｏｆＭａｃｈｒｅｆｌｅｃｔｉｏｎｆｏｒｍｅｄａｆｔｅｒｔｈｅｉｍｐｉｎｇｅｍｅｎｔｏｆａｗｅａｋｐｌａｎｅｓｈｏｃｋｗａｖｅｏｎａｗｅｄｇｅ，ｗｉｔｈｓｈｏｃｋＭａｃ... 详细信息

Ａｂｓｔｒａｃｔ：ＴｈｅｉｎｖｅｓｔｉｇａｔｉｏｎｏｆＭａｃｈｒｅｆｌｅｃｔｉｏｎｆｏｒｍｅｄａｆｔｅｒｔｈｅｉｍｐｉｎｇｅｍｅｎｔｏｆａｗｅａｋｐｌａｎｅｓｈｏｃｋｗａｖｅｏｎａｗｅｄｇｅ，ｗｉｔｈｓｈｏｃｋＭａｃｈｎｕｍｂｅｒＭｓｎｅａｒ１，ｉｓｓｔｉｌａｎｏｐｅｎｐｒｏｂｌｅｍ［１２］．Ｉｔ＇ｓｄｉｆｉｃｕｌｔｆｏｒｓｈｏｃｋｔｕｂｅｅｘｐｅｒｉｍｅｎｔｓｗｉｔｈｉｎｔｅｒｆｅｒｏｍｅｔｅｒｔｏｄｅｔｅｃｔｃｏｎｔａｃｔｄｉｓｃｏｎ－ｔｉｎｕｉｔｉｅｓ，ｉｆｉｔｉｓｔｏｏｗｅａｋ；ａｌｓｏｄｉｆｉｃｕｌｔｔｏｃａｔｃｈｗｉｔｈｄｕｅａｃｃｕｒａｃｙｔｈｅｔｒａｎｓｉｔｉｏｎｃｏｎｄｉｔｉｏｎｂｅｔｗｅｅｎＭａｃｈｒｅｆｌｅｃｔｉｏｎａｎｄｒｅｇｕｌａｒｒｅｆｌｅｃｔｉｏｎ．Ｔｈｅｉｎｔｅｒｅｓｔｔｏｔｈｉｓｐｈｅｎｏｍｅｎｏｎｉｓｃｏｎｔｉｎ－ｕｉｎｇ，ｅｓｐｅｃｉａｌｙｆｏｒｗｅａｋｓｈｏｃｋｓ，ｂｅｃａｕｓｅｔｈｅｒｅｗａｓｓｙｓｔｅｍａｔｉｃｄｉｓｃｒｅｐａｎｃｙｂｅｔｗｅｅｎｓｉｍ－ｐｌｉｆｉｅｄｔｈｒｅｅｓｈｏｃｋｔｈｅｏｒｙｏｆｖｏｎＮｅｕｍａｎｎ［８］ａｎｄｓｈｏｃｋｔｕｂｅｒｅｓｕｌｔ

关键词： weak reflection Mach reflection anti-diffusion

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A novel endorectal RF coil for high resolution MRI and spectroscopy of the prostate

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Progress in Natural science:Materials International 2005年第5期15卷 472-476页

作者： ZHANG Hongjie 1,2, SONG Xiaoyu1, WANG Xiaoying3. XU Pingfang1 and BAO Shanglian1*(1. beijing Key Laboratory of Medical Physics & Engineering, peking university, beijing 100871, China 2. Navy General Hospital, beijing 10003., China 3. peking university First Hospital, beijing 10003., China) beijing Key Laboratory of Medical Physics & Engineering Peking University Beijing 100871 China Navy General Hospital Beijing 100037 China peking university First Hospital Beijing 100034 China

The diagnosis of prostate diseases by magnetic resonance imaging (MRI) in vivo is sometimes difficult for the lower signal to noise ratio (SNR). To increase the SNR of the prostate image, we designed a RF coil that can be inserted into rectum and was named endorectal coil. The properties of RF coil were evaluated using a network analyzer. Moreover the images and spectroscopy of a special phantom were acquired and the results were compared to those of the commercial TORSO coil (G.E. Medical Systems, USA). Our coil gave a significantly higher SNR at the region of interest (ROI). The achieved high local SNR and resulting high spatial resolution would add more anatomic and biochemical information to the diagnosis of prostate diseases.

关键词： MRI RF coil endorectal coil.

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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

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Positioning localities from spatial assertions based on Voronoi neighboring

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science China(Technological sciences) 2010年第S1期53卷 143-149页

作者： GONG YongXi 1,2,3.LI GuiCai 1,LIU Yu 2 & YANG Jian 1 1 Shenzhen Key Lab of Recycling Economy,peking university Shenzhen Graduate School,Shenzhen 518055,China 2Institute of Remote Sensing and Geographical information Systems,peking university,beijing 100871,China 3.ollege of Urban and Environmental science,peking university,beijing 100871,China peking Univ Shenzhen Grad Sch Shenzhen Key Lab Recycling Econ Shenzhen 518055 Peoples R China peking Univ Inst Remote Sensing & Geog Informat Syst Beijing 100871 Peoples R China peking Univ Coll Urban & Environm Sci Beijing 100871 Peoples R China

With the rapid development of Internet,much spatial information contained in non-structured or semi-structured documents is available on the World Wide *** such documents,localities are always textually described using spatial relationships and named places,instead of numerical ***,extracting positional information from locality descriptions is an important *** this paper,we bridge two aspects of locality descriptions,namely generating locality descriptions and positioning localities,and provide a method to compute probability density according to the selection probability of a reference object to describe the position of the target *** operation on uncertainty field is used to deal with locality description involving multiple reference *** metrics are introduced to measure the results of positioning *** choose the mixed selection probability function based on Euclidean distance and Voronoi stolen-area to compute probability density ***,we use three cases to demonstrate the proposed methods.

关键词： geographic information science positioning locality Voronoi neighboring probability density function

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Two possible mechanisms for vortex self-organization

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science China Earth sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2, ZHOU Xiuji1 & GAO Shouting3.1. Chinese Academy of Meteorological sciences, beijing 100081, China 2. Department of Space information science, Nanjing university of information science and Technology, Nanjing 210044, China 3. Institute of Atmospheric Physics, Chinese Academy of sciences, beijing 100029, China 2. Department of Environmental science Nanjing University of Information Science and Technology Nanjing 210044 China 1. Chinese Academy of Meteorological sciences Beijing 100081 China 3. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

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Influence of magnetic current on the ground state entanglement in an isotropic transverse XY chain

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Progress in Natural science:Materials International 2007年第10期17卷 1147-1151页

作者： Liu Dan1,2 , Zhang Yong3.and Long Guilu1,2(1. Key Laboratory for Atomic and Molecular Nanosciences, and Department of Physics, Tsinghua university, beijing 100084, China 2.{3. of Quantum information science and Technology, Tsinghua National Laboratory for information science and Technology, beijing 100084, China 3. Institute of Physics, School of sciences, beijing university of Posts and Telecommunications, beijing 100876, China) Key Laboratory for Atomic and Molecular Nanosciences and Department of Physics Tsinghua University Beijing 100084 China center of Quantum information science and Technology Tsinghua National Laboratory for information Science and Technology Beijing 100084 China Institute of Physics School of Sciences Beijing University of Posts and Telecommunications Beijing 100876 China

We study the ground state entanglement in a three-qubit XY chain under the influence of a magnetization current. It is found that the ground state changes from a W state to a disentangled state as the magnetic field varies. When the Lagrange multiplier λ>3. namely under a strong magnetic current, the ground state holds onto a W state for a large range of the magnetic field strength. A phase transition to the magnetization-current phase occurs under a certain condition.

关键词： Heisenberg-XY chain magnetic-current phase transition.

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Current Situation of Theoretical Research of Library science in China

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图书情报工作 1996年第4期 29-34页

作者： Wu Weici Luo Zhiyong(Department of Library and information science, peking university,{3.)

On the basis of characterizing the current situation of theoretical research of library science in China, the authors summarize the main viewpoints and achievements on eight aspects of library science theories.

关键词： library science theory China

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