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Molecular mechanism of dehydrin in response to environmental stress in plant

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Progress in Natural Science:Materials International 2007年第3期17卷 237-246页

作者： ZHANG Yuxiu , WANG Zi and XU Jin (Department of Bioengineering, School of Chemical and Environmental Engineering, china university of Mining and Technology (beijing), beijing 100083, china Department of Biology, graduate university of chinese academy of sciences, beijing 100049, china) [a]Department of Bioengineering School of Chemical and Environmental Engineering China University of Mining and Technology (Beiing) Beijing China [b]Department of Biology Graduate University of Chinese Academy of Sciences Beijing China

Dehydrins, known as the D-11 subgroup of late embryogenesis abundant (LEA) protein, are an immunologically distinct family of proteins, which typically accumulate in desiccation-tolerant seed embryo or in vegetative tissues in response to various environmental stresses such as drought, salinity and freezing. The existence of conservative sequences designated as K, S, and Y segments is a structural feature of dehydrins, and the K segment found in all dehydrins represents a highly conserved 15 amino acid motif (EKKGIMDKIKEKLPG) and forms an amphiphilicα-helix. According to the arrangement of these domains and clustering analysis, dehydrins are subdivided into 5 subtypes: YnSK, Kn, KnS, SKn and YnK. Different types of dehydrins are induced by different environmental stress in plants. Study results showed that dehydrins might play important protective roles under abiotic stress via a number of different mechanisms, including improving or protecting enzyme activities by the cryoprotective activity in responding to freeze/thaw or dehydration; stabilizing vesicles or other endomembrane structures by function as the membrane stabilizer during freeze induced dehydration, and preventing the membrane system from the oxidative damage induced by reactive oxygen radicals as the radical scavenger. Here, the gene expression and molecular mechanisms of dehydrin in response to stress in plants are discussed.

关键词： dehydrin stress mechanism.

New research progress on the ultrastructure of tectonically deformed coals

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Progress in Natural Science:Materials International 2009年第11期19卷 1455-1466页

作者： Yiwen Ju,Xiaoshi Li Laboratory of Computational Geodynamics,College of Earth Science,graduate university of chinese academy of sciences,beijing 100049,china [a]Laboratory of Computational Geodynamics College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China

The structure of tectonically deformed coals shows some characteristics and regulations on the ultra-scale when influenced by different factors such as temperature,pressure and directional *** of the macromolecular structure may induce changes in the nano-scale pore structure,which are very important for gas adsorption and *** geological impact of different mechanisms of deformation on different types of ultrastructure of tectonically deformed coals is not only of significance as a topic for scientific research, but also in studying environments of metamorphism-deformation at differing metamorphic *** research is also very important in studying the accumulation and occurrence conditions of coalbed methane gas,mechanisms of coal and gas outbursts,predictions of coalbed methane resources and dangers of coal and gas *** paper analyzes current research,within china and other countries, in the ultrastructure of tectonically deformed *** research includes(1) structural models of tectonically deformed coals;(2) the relationship between ultrastructure and stress;(3) the structure of tectonically deformed coals and its strain *** results are also based on our own experiments including vitirnite reflectance(Ro,max),X-ray diffraction(XRD) and nuclear magnetic resonance (NMR(CP/MAS + TOSS)).We discuss the important effects of the structure of tectonically deformed coals and their physical properties,and then point out some problems concerning the research progress of tectonically deformed coals.

关键词： Tectonically deformed coals Ultrastructure Pore structure Tectonic stress Strain environment

An Efficient High-Resolution Shock-Capturing Scheme for Multi-Dimensional Flows I. Hydrodynamics

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chinese Journal of Astronomy and Astrophysics 2006年第6期6卷 680-688页

作者： Cong Yu National Astronomical Observatories / Yunnan Astronomical Observatory, chinese academy of sciences, Kunming 650011 graduate School of chinese academy of sciences, beijing 100049 graduate School of chinese academy of sciences Beijing 100049

Many problems at the forefront of theoretical astrophysics require a treatment of dynamical fluid behavior. We present an efficient high-resolution shock-capturing hydrodynamic scheme designed to study such phenomena. We have implemented a weighted, essentially non-oscillatory （WENO） scheme to fifth order accuracy in space, lILLE approximate Riemann solver is used for the flux computation at cell interface, which does not require spectral decomposition into characteristic waves and so is computationally friendly. For time integration we apply a third order total variation diminishing （TVD） Runge-Kutta scheme. Extensive testing and comparison with schemes that *** characteristic decomposition are carried out demonstrating the ability of our scheme to address challenging open questions in astrophysics.

关键词： accretion - hydrodynamics- method numerical - shock waves

Transformations and non-degenerate maps

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Science china Mathematics 2005年第z1期48卷 195-205页

作者： LI Baokui & WANG Yuefei Institute of Mathematics, academy of Mathematics and System sciences, chinese academy of sciences, beijing 100080, china graduate School, chinese academy of sciences, beijing 100080, china 1. Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences 100080 Beijing China 2. graduate School Chinese Academy of Sciences 100080 Beijing China

We shall prove the equivalences of a non-degenerate circle-preserving map and a M(o)bius transformation in ^Rn, of a non-degenerate geodesic-preserving map and an isometry in Hn of a non-degenerate line-preserving map and an affine transformation in Rn. That a map is non-degenerate means that the image of the whole space under the map is not a circle, or geodesic or line respectively. These results hold without either injective or surjective, or even continuous assumptions, which are new and of a fundamental nature in geometry.

关键词： M(o)bius transformation, circle-preserving map, non-degenerate map.

Existence of unbiased estimate of regression parameters in simple linear EV models

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Science china Mathematics 2005年第7期48卷 915-928页

作者： LIU Jixue & CHEN Xiru Department of Statistics and Finance, university of Science and Technology of china, Hefei 230026, china Department of Mathematics, graduate School of chinese academy of sciences, beijing 100049, china 1. Department of Statistics and Finance University of Science and Technology of China 230026 Hefei China 2. Department of Mathematics Graduate School of Chinese Academy of Sciences 100049 Beijing China

It is well known that for one-dimensional normal EV regression model X = x+ u,Y =α+βx+e, where x, u, e are mutually independent normal variables and Eu=Ee=0, the regression parameters a and β are not identifiable without some restriction imposed on the parameters. This paper discusses the problem of existence of unbiased estimate for a and β under some restrictions commonly used in practice. It is proved that the unbiased estimate does not exist under many such restrictions. We also point out one important case in which the unbiased estimates of a and β exist, and the form of the MVUE of a and β are also given.

关键词： EV regression model unbiased estimate identiflability.

Thermal analysis of the baffle structure of the Solar Space Telescope

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Science china(Physics,Mechanics & Astronomy) 2010年第9期53卷 1755-1764页

作者： LI Rong1,2,3 & WANG Sen1,3 1 National Astronomical Observatories,chinese academy of sciences,beijing 100012,china 2 graduate university of chinese academy of sciences,beijing 100049,china 3 Key Laboratory of Solar Activity,National Astronomical Observatories of chinese academy of sciences,beijing 100012,china 1. National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Key Laboratory of Solar Activity National Astronomical Observatories of Chinese Academy of Sciences Beijing 100012 China

The SST(Space Solar Telescope) is an astronomical telescope with a primary mirror of 1 m in *** observes the sun with a small view field to ensure that its high spatial resolution imaging has 0.1″-0.15″ and high SNR(signal to noise ratio).Surrounding the small view field is still the sun,which is an intense source of both heat and stray *** baffles(the main baffle,the aperture,and the outer baffle),which are used to eliminate the stray light,will change the thermal flux in the SST and will weaken the effect of the thermal control *** this study,the compatibility analysis of the thermal effect of baffle structures in SST is *** GCF(Geometry Composing Function) and BRDF(Bidirectional Reflectance Distribution Function),which are two inherent related parameters in the compatibility analysis,are *** objective and method of the compatibility analysis are *** the thermal analysis software,the temperature fields are calculated for different lengths of the main baffle,different radii of apertures,different lengths of the outer baffle with a 3' tilt angle and 16' tilt angle,and different tilt angles of the outer baffle with a 200 mm length.A series of configurations and sizes of the baffles are studied with the goals of both thermal control and elimination of stray *** design of the baffle structure of SST is achieved:the main baffle of length 4100 mm,the internal shield of radius 494 mm,the outer baffle of length 200 mm,and the outer baffle of tilt angle 3' are successfully *** paper presents the relationship between the thermal control design and stray light elimination plan in the *** aims of the optimal design of the baffle structure of SST are *** thoughts and methods of the optimal analysis are also useful for similar optical telescopes designed for solar observation.

关键词： baffle the main baffle the outer baffle GCF BRDF

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

A Kinematic Thermal Model for Descending Slabs with Velocity Boundary Layers

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地学前缘 2009年第S1期16卷 195-196页

作者： Keliang Zhang graduate university of the chinese academy of sciences,College of Earth Science,beijing 100049,china.

Kinematic models compute the temperature distribution by prescribing a constant convergent velocity for the subducting slab,resulting in an artificial velocity discontinuity,which may accelerate the heating of subducting *** the purpose to moderate the influence of such artificial discontinuity, we construct a 2D thermal model for subduction zones with a velocity boundary layer,within which the velocities decrease linearly with the distance from the interfaces of *** are calculated

关键词： kinematic model thermal structure subduction zone velocity boundary layer finite element method

Comparison of dynamic changes in endogenous hormones and sugars between abnormal and normal Castanea mollissima

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Progress in Natural Science:Materials International 2008年第6期18卷 685-690页

作者： Tao Liua,b,Yunqian Hua,*,Xiaoxian Li a aKunming Institute of Botany,chinese academy of sciences,Kunming 650204,china bgraduate university of the chinese academy of sciences,beijing 100049,china Kunming Institute of Botany Chinese Academy of Sciences Kunming 650204 China graduate university of the chinese academy of sciences Beijing 100049 China

To elucidate the possible functions of endogenous hormones in the flowering of chestnut,concentrations of four endogenous hor-mones[indole-3-acetic acid(IAA),gibberellic acid(GA),abscisic acid(ABA),zeatin riboside(ZR))and the soluble sugars content were measured in both normal and developmentally abnormal chinese chestnut(Castanea mollissima)during flowering and fruiting *** results showed that the contents of ZR,ABA,and GA exhibited a significant dierent pattern in normal trees from that in abnormal trees,while the contents of IAA and soluble sugars showed a similar change pattern between *** results suggest that quantitative changes in endogenous hormones may correspond to dierent flowering and fruiting mechanisms.

关键词： Castanea mollissima Endogenous hormones Soluble sugars