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Application of three-dimensional discrete element face-to-face contact model with fissure water pressure to stability analysis of landslide in Panluo iron mine

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Science china(Technological sciences) 2005年第z1期48卷 146-156页

作者： ZHANG Lei1,2, WEI Zuoan1, LIU Xiaoyu1 & LI Shihai1 1.Institute of Mechanics, chinese academy of sciences, Beijing 100080, china 2.graduate school, chinese academy of sciences, Beijing 100060, china chinese Acad Sci Inst Mech Beijing 100080 Peoples R China chinese Acad Sci Grad Sch Beijing 100060 Peoples R China

Three-dimensional discrete element face-to-face contact model with fissure water pressure is established in this paper and the model is used to simulate three-stage process of landslide under fissure water pressure in the opencast mine, according to the actual state of landslide in Panluo iron mine where landslide happened in 1990 and was fathered in 1999. The calculation results show that fissure water pressure on the sliding surface is the main reason causing landslide and the local soft interlayer weakens the stability of slope. If the discrete element method adopts the same assumption as the limit equilibrium method, the results of two methods are in good agreement; while if the assumption is not adopted in the discrete element method, the critical φ numerically calculated is less than the one calculated by use of the limit equilibrium method for the sameC. Thus, from an engineering point of view, the result from the discrete element model simulation is safer and has more widely application since the discrete element model takes into account the effect of rock mass structures.

关键词： face-to-facecontactmodel, fissure water pressure, three-dimensional discrete element method,landslide.

Multiple Signaling Pathways Control Tbx6 Expression during Xenopus Myogenesis

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Acta Biochimica et Biophysica Sinica 2004年第6期36卷 390-396页

作者： Pan-Feng FANG, Rui-Ying HU, Xing-Yue HE, and Xiao-Yan DING* Laboratory of Molecular and Cell Biology, Laboratory of Stem Cell Biology & Institute of Biochemistry and Cell Biology, shanghai Institutes for Biological sciences, chinese academy of sciences, graduate school of the chinese academy of sciences, shanghai 200031, china Laboratory of Molecular and Cell Biology Laboratory of Stem Cell Biology & Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China

Tbx6 is critical for somite specification and myogenesis initiation. It has been shown that Activin/Nodal, VegT/Nodal, FGF, and BMP signaling pathways are involved early in specifying mesoderm or later in patterning mesoderm, and Xnot plays roles in setting up the boundary between notochord and paraxial mesoderm. In this study, we introduce the dominant negative form of above genes into embryos to evaluate if they are responsible for regulating Tbx6 expression. The results show that: (1) Activin/Nodal and VegT/Nodal signals are necessary for both initiation and maintenance of Tbx6 expression, and Nodal is sufficient to induce ectopic Tbx6 expression; (2) FGF signal is necessary for the initiation and maintenance of Tbx6, but it is not sufficient to induce Tbx6 expression; (3) BMP is also necessary for the expression of Tbx6, and the induction of Tbx6 expression by BMP is dose dependent; (4) Xnot has no effect on the expression of Tbx6. Our results suggest that several signaling pathways are involved in regulating Tbx6 expression, and pave the route to reveal the molecular mechanism of initiating myogenesis.

关键词： Tbx6 FGF BMP Activin/Nodal VegT/Nodal

Trend of urban system structure under the restriction of water and land resources in Xinjiang

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chinese Science Bulletin 2006年第A01期51卷 179-188页

作者： ZHANG Xiaolei & LEIJun Xinjiang Institute of Ecology and Geography, chinese academy of sciences, Urumqi 830011, china Institute of Geographical Science and Natural Resources Research, chinese academy of sciences, Beijing 100101, china graduate school, chinese academy of sciences, Beijing 100039, china chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China

根据在 Xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 Xinjiang 的大多数城市和镇在水资源的缺乏水资源... 详细信息

根据在 Xinjiang 影响城市的开发和城市的系统结构的水和陆地资源上的研究，这篇论文分析利用地位和城市的水资源的缺乏。城市的水资源的消费和浪费在一个增加趋势，这被考虑。然而，在 Xinjiang 的大多数城市和镇在水资源的缺乏水资源的废物是严肃的，特别在小镇上。megapolis 和中等城市的发展被有限陆地资源显然限制。尽管有扩展小城市和镇的相对大的空格，水和陆地资源的输出好处是低的。为了完成城市的系统的顺序的扩大，在 Xinjiang 组织，在都市化的快速的发展拿一个圆和三条带和节俭资源的策略的城市的空间发展模式被建议。

关键词：城镇体系结构水资源土地资源供水能力新疆

SAR IMAGING SIMULATION OF HORIZONTAL FULLY TWO-DIMENSIONAL INTERNAL WAVES

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Journal of Hydrodynamics 2006年第3期18卷 294-302页

作者： SHEN Hui HE Yi-Jun Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China graduate school of the chinese academy of sciences Beijing 100039 China

Based on the research of Lynett and Liu, a new horizontal fully two-dimensional internal wave propagation model with rotation effect was deduced, which can be used to simulate the characteristics of internal waves in a horizontal fully two-dimensional plane. By combining the imaging mechanism of Synthetic Aperture Radar（SAR）, a simulation procedure was fatherly acquired, which can simulate the propagation characteristics of oceanic internal waves into SAR images. In order to evaluate the validity of the proposed simulation procedure, case studies are performed in South china Sea and results from simulation procedure are analyzed in detail. A very good consistency was found between the simulation results and satellite images. The proposed simulation procedure will be a possible foundation for the quantitative interpretation of internal waves from fully two-dimensional satellite images.

关键词： oceanic internal waves imaging simulation,Synthetic Aperture Radar (SAR)

Effect of concentration on surfactant micelle shapes——A molecular dynamics study

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Science china Chemistry 2005年第5期48卷 470-475页

作者： GAO Jian1,2, GE Wei1 & LI Jinghai1 1. Multiphase Reaction Laboratory, Institute of Process Engineering, chinese academy of sciences, Beijing 100080, china 2. graduate school of The chinese academy of sciences, Beijing 100085, china 1. Multiphase Reaction Laboratory Institute of Process Engineering Chinese Academy of Sciences 100080 Beijing China 2. graduate school of The chinese academy of sciences 100085 Beijing China

Many aspects of the behavior of surfactants have not been well understood due to the coupling of many different mechanisms. Computer simulation is, therefore, attractive in the sense that it can explore the effect of different mechanisms separately. In this paper, the shapes, structures and sizes of sodium dodecylbenzenesulfonate (SDBS) micelles under different con-centrations in an oil/water mixture were studied via molecular dynamics (MD) simulations using a simplified atomistic model which basically maintains the hydrophile and lipophile properties of the surfactant molecules. Above the critical micellar concentration (cmc), surfactant molecules ag-gregate spontaneously to form a wide variety of assemblies, from spherical to rodlike, wormlike and bilayer micelles. Changes in their ratios of the principle moments of inertia (g1/g3, g2/g3) in-dicated the transition of micelle shapes at different concentrations. The aggregation number of micelle is found to have a power-law dependence on surfactant concentration.

关键词： surfactant, MD simulation, sodium dodecylbenzenesulfonate, micelle shape.

miRNAs modulate the drug response of tumor cells

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Science china(Life sciences) 2009年第9期52卷 797-801页

作者： WU XueMei1,3 & XIAO HuaSheng1,2 1 Center of Functional Genomics,Key Laboratory of System Biology,shanghai Institutes for Biological sciences,chinese academy of sciences,shanghai 200031,china 2 National Engineering Center for Biochip at shanghai,shanghai 201203,china 3 graduate University of chinese academy of sciences,shanghai 200031,china Center of Functional Genomics Key Laboratory of System Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China National Engineering Center for Biochip at shanghai Shanghai 201203 China graduate University of chinese academy of sciences Shanghai 200031 China

Chemotherapy is one of the major treatments of malignant carcinomas. However,its efficiency is affected by both intrinsic and acquired resistance to anticancer drugs. The cellular mechanisms of drug resistance include the overexpression of energy-dependent transporters that eject anticancer drugs from cells such as p-glycoprotein and multidrug resistance related protein (MRP),the mutation of drug targets,the activation of DNA repair pathways,the defects in cellular death pathways and so on. The genetic and epigenetic changes of these genes can lead to cancer drug resistance. Among these mechanisms,microRNAs (miRNAs) which are critical and essential for many important processes such as development,differentiation,and even carcinogenesis have been reported to regulate the chemosen-sitivity of tumor cells. In this paper we briefly review the relationship between miRNA and cancer drug resistance.

关键词： cancer drug resistance miRNAs

Transient species and its properties of melatonin

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Science china Chemistry 2006年第4期49卷 308-314页

作者： ZHU Hongping1,2, ZHANG Zhaoxia1,2, ZHAO Hongwei1, WANG Wenfeng1 & YAO Side1 1. shanghai Institute of Applied Physics, chinese academy of sciences, shanghai 201800, china 2. graduate University of the chinese academy of sciences, Beijing 100049, china 1. shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China 2. graduate University of the chinese academy of sciences Beijing 100049 China

The photo-physical and photo-chemical properties of melatonin (ML) werestudied by 266 nm laser flash photolysis (LFP). ML undergoes photo-ionization to produce radicalcation of ML (ML^(·+))and hydrated electrons (e_(aq)^-), while excited triplet state ~3ML~* is alsoformed during photolysis. The oxidation via one electron transfer from ML to SO_4^(·+) and thetriplet state of riboflavin (~3RF~*) has been also investigated and the rate constants for theprocess have been determined to be 8.0x10^9 and 1.4x10^9 L·mol^(-1)·s^(-1) respectively. Theradical cation of 2,2''-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS^(·+)) scavengingcapacities of melatonin and other antioxidants are compared in this paper.

关键词： melatonin, laser flash photolysis, photoionization, triplet state.

Antitumor Effect of a Novel Adeno-associated Virus Vector Targeting to Telomerase Activity in Tumor Cells

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Acta Biochimica et Biophysica Sinica 2004年第7期36卷 492-500页

作者： Yi-Gang WANG1,2#, Jin-Hui WANG1#, Yan-Hong ZHANG1, Qing GU2*, and Xin-Yuan LIU1* 1Institute of Biochemistry and Cell Biology, shanghai Institutes for Biological sciences, chinese academy of sciences, graduate school of the chinese academy of sciences, shanghai 200031, china school of Life Science, Nanchang University, Nanchang 330047, china Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences Shanghai 200031 China

Telomerase activity is a wide tumor marker. Human telomerase reverse transcriptase (hTERT), the catalytic subunit of the telomerase, is transcriptionally upregulated exclusively in about 90% of cancer cells. In this study, we constructed a novel adeno-associated virus (AAV) vector containing the human interferon-β (hIFN-β) gene under the control of hTERT promoter (AAV-hTERT-hIFN-β) and investigated its antitumor effect against various human cancer cells in vitro. AAV-hTERT-hIFN-β displayed cancer-specific hIFN-β expression and cytotoxicity. The cytotoxic ratio was positively correlated with the time length of infection. AAV-hTERT-hIFN-β-mediated apoptotic morphology was observed by transmission electron microscopy. Flow cytometry assay also revealed that the cytotoxicity of AAV-hTERT-hIFN-β was mainly an apoptotic process. These data indicate that AAV in combination with hTERT-mediated therapeutic gene expression may open new possibilities for long-lasting and targeting gene therapy of varieties of cancers.

关键词： adeno-associated virus (AAV) telomerase hTERT promoter human interferon-β cancer

Analysis and application of automatic deformation monitoring data for buildings and structures of mining area

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中国有色金属学会会刊：英文版 2011年第S3期21卷 516-522页

作者： XIAO Jie1, 2, 3, ZHANG Jin4 1. Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 430077, china 2. Key Laboratory of Dynamic Geodesy, Institute of Geodesy and Geophysics, chinese academy of sciences, Wuhan 430077, china 3. graduate school of chinese academy of sciences, Beijing 100049, china 4. Department of Surveying and Mapping, Taiyuan University of Technology, Taiyuan 030024, china Taiyuan Univ Technol Dept Surveying & Mapping Taiyuan 030024 Peoples R China chinese Acad Sci Inst Geodesy & Geophys Key Lab Dynam Geodesy Wuhan 430077 Peoples R China chinese Acad Sci Grad Sch Beijing 100049 Peoples R China

The buildings and structures of mines were monitored automatically using modern surveying technology. Through the analysis of the monitoring data, the deformation characteristics were found out from three aspects containing points, lines and regions, which play an important role in understanding the stable state of buildings and structures. The stability and deformation of monitoring points were analysed, and time-series data of monitoring points were denoised with wavelet analysis and Kalman filtering, and exponent function and periodic function were used to get the ideal deformation trend model of monitoring points. Through calculating the monitoring data obtained, analyzing the deformation trend, and cognizing the deformation regularity, it can better service mine safety production and decision-making.

关键词： wavelet analysis Kalman filtering deformation monitoring data analysis mine