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Milestone of the meridian science──970th anniversary of the Chinese Bronze Statue of Meridian

Chinese Science Bulletin 1998年第5期43卷 353-362页

作者： zhang renji college of life sciences, peking university, beijing 100871, china college of life sciences Peking University Beijing 100871 China

For more than a thousand years, Chinese people were aware of the transmitted sensations by the application of needles on the body surface. This practice is called acupuncture. Acupuncture had been recorded and transcribed in writings and in drawings, until finally the acupoints were inscribed onto a bronze statue. The bronze statue was called the Meridian Figure. Deeply embodied in the bronze statue is a tripartite confrontation-prism representation of the humans body. This concept was a great scientific achievement in ancient china. The author traces the history of Meridian science described in traditional Chinese medical terms. Then he explores a clear analogy of the meridian pathway (MP) phenomenon. In a model system, by using a simple segmental in vertebrate, certain parallels can be demonstrated with the meridian concept. For example, the author demonstrated a clear correlation rule among the central mechano-sensory channels, and characteristics of positional discrimination in individual nerve cells from different receptive field inputs. The evidence suggests that the MP phenomenon is an objective neurobiological response. To clarify the research objective in this paper, the author suggests that the MP is a bi-directional pathway along which a positional message signal is transmitted. This phenomenon is evoked by physical stimulation, transmitted linearly across the human body segments, and is perceived by the brain. The MP consists of low resistance paths, is connected by the liquid media contained in the apposite membranous structure. At the cellular level, the regulation functions of MP must pass through along this low resistance path. Two aspects of the modern Meridian research are the functional regulation and the mechanism of intercellular liquid modulation at the nanometer level.

关键词： meridian pathway tripartite confrontation-prism coordinate position discriminative recognition apposite membranous structure.

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GM-CSF-induced Ca_(2+) -activated non-voltage-dependent inwardly rectifying K_+ channel in murine peritoneal exudate macrophages

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Chinese Science Bulletin 1997年第11期42卷 947-952页

作者： zhang Xiaofeng, FENG Meifu, WU Caihong and ZHOU Pei’aiState Key Laboratory of Biomembrane and Membrane Biotechnology, Chinese Academy of sciences, beijing 100080, china 1 . In-stitute of Zoology, Chinese Academy of sciences, beijing 100080, china 2 college of life sciences, peking university, beijing 100871, china State Key Laboratory of Biomembrane and Membrane Biotechnology Chinese Academy of Sciences Beijing 100080 China

GRANULOCYTE-MACROPHAGE colony-stimulating factor(GM-CSF),a member in the family ofglycoprotein cytokines,can not only act to stimulate proliferation of immature progenitors,butalso enhance differentiated functions of mature effector *** has two kinds of biologicaleffects on mature effector cells,*** effect and indirect *** latter is also

关键词： K+ channel patch clamp GM-CSF macrophage.

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LDFF,the large molecular weight DNA fragmentation factor,is responsible for the large molecular weight DNA degradation during apoptosis in Xenopus egg extracts

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Cell Research 2004年第2期14卷 134-140页

作者： Zhi Gang LU, Chuan Mao zhang~*, Zhong He ZHAI~* Department of Cell Biology and Genetics, college of life sciences, peking university, beijing 100871, china. Department of Cell Biology and Genetics College of Life Sciences Peking University Beijing 100871 China.

DNA degradation is a biochemical hallmark in apoptosis. It has been demonstrated in many cell types that there are two stages of DNA fragmentation during the apoptotic execution. In the early stage, chromatin DNA is cut into large molecular weight DNA fragments, although the responsible nuclease(s) has not been recognized. In the late stage, the chromatin DNA is cleaved further into short oligonucleosomal fragments by a well-characterized nuclease in apoptosis, the caspase-activated DNase (CAD/DFF40). In this study, we demonstrate that large molecular weight DNA fragmentation also occurs in Xenopus egg extracts in apoptosis. We show that the large molecular weight DNA fragmentation factor (LDFF) is not the Xenopus CAD homolog XCAD. LDFF is activated by caspase-3. The large molecular weight DNA fragmentation activity of LDFF is Mg2+-dependent and Ca2+-independent, can occur in both acidic and neutral pH conditions and can tolerate 45℃ treatment. These results indicate that LDFF in Xenopus egg extr

关键词： apoptosis caspase-activated DNase (CAD) large molecular weight DNA fragmentation factor (LDFF).

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Synthesis and Crystal Structure of 4,6Di-tert-butyl-2-hydroxy-3-(N-1-phenylethyliminomethyl) phenyl bis(triphenylphosphine)palladium bromide

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Chinese Journal of Structural Chemistry 1999年第4期18卷 54-59页

作者： XU JiaXi\ zhang ZeYing\= (college of Chemistry and Molecular Engineering, peking university, beijing 100871, china) Coll. of Chem. and Molec. Eng. Peking University Beijing 100871 China

１ＩＮＴＲＯＤＵＣＴＩＯＮＰａｌａｄｉｕｍｃｏｍｐｌｅｘｅｓｓｕｃｈａｓｔｅｔｒａｋｉｓ（ｔｒｉｐｈｅｎｙｌｐｈｏｓｐｈｉｎｅ）ｐａｌａｄｉｕｍａｒｅａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｃａｔａｌｙｓｔｓｉｎｔｈｅｒｅａ... 详细信息

１ＩＮＴＲＯＤＵＣＴＩＯＮＰａｌａｄｉｕｍｃｏｍｐｌｅｘｅｓｓｕｃｈａｓｔｅｔｒａｋｉｓ（ｔｒｉｐｈｅｎｙｌｐｈｏｓｐｈｉｎｅ）ｐａｌａｄｉｕｍａｒｅａｋｉｎｄｏｆｉｍｐｏｒｔａｎｔｃａｔａｌｙｓｔｓｉｎｔｈｅｒｅａｃｔｉｏｎｏｆｃａｒｂｏｎｃａｒ...

关键词： palladium complex synthesis molecular structure crystal structure

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PII,the key regulator of nitrogen metabolism in the cyanobacteria

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Science china(life sciences) 2008年第12期51卷 1056-1065页

作者： zhang Ying & ZHAO JinDong State Key Laboratory of Protein and Plant Genetic Engineering, college of life Science, peking university, beijing 100871, china 1. State Key Laboratory of Protein and Plant Genetic Engineering College of Life Science Peking University Beijing 100871 China

PII proteins are a protein family important to signal transduction in bacteria and plants. PII plays a critical role in regulation of carbon and nitrogen metabolism in cyanobacteria. Through conformation change and covalent modification, which are regulated by 2-oxoglutarate, PII interacts with different target proteins in response to changes of cellular energy status and carbon and nitrogen sources in cyanobacteria and regulates cellular metabolism. This article reports recent progress in PII research in cyanobacteria and discusses the mechanism of PII regulation of cellular metabolism .

关键词： carbon metabolism cyanobacteria nitrogen metabolism PII protein

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Lattice Boltzmann Method used for the aircraft characteristics computation at high angle of attack

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Science china(Technological sciences) 2010年第8期53卷 2068-2073页

作者： DU TeZhuan,LI XiangQun,zhang XiaLing&WANG YiWei college of Engineering,peking university,beijing 100871,china 1. college of Engineering Peking University Beijing 100871 China

Traditional Finite Volume Method(FVM)and Lattice Boltzmann Method(LBM)are both used to compute the high angle attack aerodynamic characteristics of the benchmark aircraft model named *** though the software requires flow on the order of Ma<0.4,simulation at Ma=0.5 is run in PowerFLOW after theoretical *** consistency with the wind tunnel testing is satisfied,especially for the LBM which can produce perfect results at high angle *** can accurately capture the detail of flows because it is inherently time-dependent and parallel and suits large-scale computation very well.

关键词： LBM CFD high AOA

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Simultaneous Recrystallization and Oxidation Behavior of Mn-Containing IF Steel

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Journal of Iron and Steel Research International 2012年第8期19卷 67-74页

作者： zhang Zuo-tai, zhang Ying-yi (Department of Energy and Resources Engineering, college of Engineering, peking university, beijing 100871, china) Department of Energy and Resources Engineering College of Engineering Peking University Beijing 100871 China

The recrystallization and oxidation of a Mn-containing interstitial free (IF) steel were investigated simultaneously using confocal scanning laser microscope (CSLM) under controlled atmosphere of Ar 95% and H2 5% (in volume percent) at different temperatures. It was found that the grain boundary played a significant role in controlling recrystallization and oxidation in overall oxidation kinetics of the steel. The surface morphology was composed of two networks along the original and new grain boundaries respectively, which did not coexist. The grain boundary moved in different directions with different velocities during annealing process. The recrystallization processes were studied by CSLM motion video through observing the moving grain boundary to estimate the time for 50% recrystallization, and the activation energy for recrystallization was therefore calculated. The oxidation mechanism was discussed through comparison of the fluxes among mass transfer of water vapor, dissociation of water vapor and outward diffusion alloying elements. The results indicated that the oxidation was controlled by the mass transfer from the bulk gas to the surface, or dissociation rate, or outward diffusion of manganese, which depended on the temperature to form a grain boundary ridge or groove.

关键词： IF steel oxidation recrystallization grain boundary

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Universal hierarchical symmetry for turbulence and general multi-scale fluctuation systems

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Acta Mechanica Sinica 2009年第3期25卷 279-294页

作者： Zhen-Su She Zhi-Xiong zhang State Key Laboratory for Turbulence and Complex Systems, college of Engineering, peking university, 100871 beijing, china State Key Laboratory for Turbulence and Complex Systems College of Engineering Peking University 100871 Beijing China

Scaling is an important measure of multi-scale fluctuation systems. Turbulence as the most remarkable multi-scale system possesses scaling over a wide range of scales. She-Leveque （SL） hierarchical symmetry, since its publication in 1994, has received wide attention. A number of experimental, numerical and theoretical work have been devoted to its verification, extension, and modification. Application to the understanding of magnetohydrodynamic turbulence, motions of cosmic baryon fluids, cosmological supersonic turbulence, natural image, spiral turbulent patterns, DNA anomalous composition, human heart variability are just a few among the most successful examples. A number of modified scaling laws have been derived in the framework of the hierarchical symmetry, and the SL model parameters are found to reveal both the organizational order of the whole system and the properties of the most significant fluctuation structures. A partial set of work related to these studies are reviewed. Particular emphasis is placed on the nature of the hierarchical symmetry. It is suggested that the SL hierarchical symmetry is a new form of the self-organization principle for multi-scale fluctuation systems, and can be employed as a standard analysis tool in the general multi-scale methodology. It is further suggested that the SL hierarchical symmetry implies the existence of a turbulence ensemble. It is speculated that the search for defining the turbulence ensemble might open a new way for deriving statistical closure equations for turbulence and other multi-scale fluctuation systems.

关键词： Turbulence. Scaling law. She-Leveque modelHierarchical symmetry Self-organization - Turbulenceensemble

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Microstructural and deformational studies on mylonite in the detachment faults of Yalashangbo dome, North Himalayan domes zone

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Progress in Natural Science:Materials International 2005年第11期15卷 1005-1013页

作者： zhang Bo, zhang Jinjiang, GUO Lei and WANG Weiliang (Department of Geology, School of Earth and Space sciences, peking university, beijing 100871, china) Department of Geology School of Earth and Space Sciences Peking University Beijing 100871 China

The Yalashangbo dome, located at the eastern end of North Himalayan domes zone, has a geometry and structure similar to those of a metamorphic core complex. Ductile shear zones formed the detachment system around the dome and these zones are composed of garnet-bearing phyllonite, mylonitic schist, mylonitic gneiss and mylonitic granite. Ductile shear fabrics developed well in my-lonitic rocks, and penetrative lineation and foliation were formed by stretched quartz and feldspar and preferred orientation of mica. Polar Mohr diagram method is used to calculate the kinematic vorticity numbers of the shear zones in the detachment system. Results indicate that the shear zone is a thinned shear zone (thinning of 23 % ) in an extensional setting which underwent a general shear dominated by simple shear. Comparison of the vorticity numbers between the northern and southern flanks of the Yalashangbo dome shows that the dome is an asymmetric system formed by a north-northwest-directed detaching unanimously. Statistical fractal analysis shows that the shapes of dynamically recrystallized quartz grains in the mylonites have characteristics of self-similarity, with fractal numbers ranging from 1.05 to 1.18. From these fractal numbers, the strain rate of the rock was deduced from 10-9.2S-1 to 10-7.3S-1, the differential paleao-stress was 13.7-25.6 MPa during the deformation happened at a temperature over 500 ℃. The ductile shear zones in the detachment system around Yalashangbo dome were formed under a high green-schist grade condition or happened simultaneously with the intrusion of granite.

关键词： Yalashangbo dome ductile shear zone kinematic vorticity fractal analysis deformation temperature strain rate.

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PROPERTIES OF POLYURETHANE ELASTOMERS BASED ON POLY (OXYETHYLENE-co-OXYTETRAMETHYLENE) DIOL

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Chinese Journal of Polymer Science 2001年第4期19卷 371-376页

作者： Chen-yu Su Guang-li zhang Hong-zhi zhang Department of Polymer Science and Engineering college of Chemistry and Molecular Engineering peking university beijing 100871, china peking Univ Dept Polymer Sci & Engn Coll Chem & Mol Engn Beijing 100871 Peoples R China

Polyurethane elastomers derived from 4,4 ' -methylene bis(phenyl isocyanate), butylene glycol and the low oxyethylene moiety content copolyether of tetrahydrofuran and ethylene oxide, obtained by copolymerization using heteropolyacid-ethylene oxide initiator system, were prepared. The polyurethanes exhibited an increased water absorption and much better low temperature resilience, which remained high even at a temperature of -3 degreesC, while that of polyurethane based upon poly(tetramethylene ether) glycol of the 'same molecular weight, i.e. being 2000, and molecular weight distribution, i.e, in the range of 1.4-1.5, starts to decrease dramatically at 5 degreesC.

关键词： polyurethane poly(oxyethylene-co-oxytetramethylene) diol low temperature resilience heteropolyacid-ethylene oxide initiator system

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