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生物物理学报 2009年第S1期25卷 217-218页

作者： Shusen Liu state key {2. of{3. and membrane biotechnology, Instutute of zoology, chinese academy of Sciences, beijing, 100101, China

Although some fusogenic proteins have been established to tether two opposite outer or inner mitochondrial membranes into contact, a prerequisite for whole mitochondrial fusion events,

关键词： Mitochondrial membrane fusion Protein-tethering Lipid-bilayer-mixing and fusion Interfacial △pH of PMF.Inter-play between membrane fusion and ATP synthesis.

Dynamics of morphological changes for mitochondrial fission and fusion

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Science China(Physics,Mechanics & Astronomy) 2010年第4期53卷 680-689页

作者： WANG ShiQi 1,2.4 , FU ChangLiang 1,2., ZHANG Yan 1,2., CHEN Quan 3.& LONG Mian 1,2.1 key {2. of Microgravity (National Microgravity {2.),{3. 100190, China 2.Center for Biomechanics and Bioengineering, institute of Mechanics, chinese academy of Sciences,{3. 100190, China 3.state key laboratory of biomembrane and membrane biotechnology, institute of zoology, chinese academy of Sciences, beijing 100101, China 4 institute of Vertebrate Paleontology and Paleoanthropology, chinese academy of Sciences,{3. 100044, China 1. key laboratory of Microgravity (National Microgravity laboratory) Beijing 100190 China2. Center for Biomechanics and Bioengineering Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China4. Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China3. State Key Laboratory of Biomembrane and Membrane Biotechnology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Mitochondria experience continuous fusion and fission in a living cell, but their dynamics remains poorly quantified. Here a theoretical model was developed, upon a simplified population balance equation (PBE), to predict the morphological changes induced by mitochondrial fission and fusion. Assuming that both fission and fusion events are statistically independent, the survival probability of mitochondria staying in the fission or fusion state was formulated as an exponentially-decayed function with time, which depended on the time-dependent distribution of the mitochondrial volume and the fission and fusion rates. Parametric analysis was done for two typical volume distributions. One was Gamma distribution and the other was Gaussian distribution, derived from the measurements of volume distribution for individual mitochondria in a living cell and purified mitochondria in vitro. The predictions indicated that the survival probability strongly depended on morphological changes of individual mitochondria and was inversely correlated to the fission and fusion rates. This work provided a new insight into quantifying the mitochondrial dynamics via monitoring the evolution of the mitochondrial volume.

关键词： mitochondria morphology fission fusion dynamics modeling

Plant protein kinase genes induced by drought, high salt and cold stresses

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chinese Science Bulletin 2000年第13期45卷 1153-1157页

作者： LIU Qiang , ZHANG Yong & Chen Shouyi1. Deparlmenl of Biological Science and biotechnology, Tsinghua University, beijing 100084, China 2. Department of Biological Science and biotechnology, Slate {3. laboratory of biomembrane and membrane biotechnology, Tsinghua University, beijing 100084, China 3. institute of Genetics, chinese {12. of Sciences, beijing 100101, China Department of Biological Science and biotechnology Tsinghua University Beijing China Department of Biological Science and biotechnology State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua University Beijing China institute of Genetics Chinese Academy of Sciences Beijing China

Drought, high salt and cold are three different kinds of environment stresses that severely influence the growth, development and productivity of crops. They all decrease the water state of plant cells, and consequently result in the harm of plant from water deficit. Several genes encoding protein kinases and induced by drought, high salt and low temperature have been isolated from Arabidopsis. These protein kinases include receptor protein kinase (RPK), MAP kinases, ribosomal-protein kinases and transcription-regulation protein kinase. The expression features of these genes and the regulatory roles of these protein kinases in stress response and signal transduction are discussed.

关键词： protein kinase environment stress signal transduction gene expression.

Molecular basis of cryptorchidism-induced infertility

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Science China(Life Sciences) 2010年第11期53卷 1274-1283页

作者： LIU YiXun & LI XiXia state key {2. of Reproductive Biology,{3., chinese academy of Sciences, beijing 100101, China 1. state key {2. of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Artificial cryptorchidism or local testicular heat treatment can induce reversible oligospermia or azoospermia in monkeys and rats via germ cell apoptosis. Local warming of monkey testes in water at 4{2.C for 2.consecutive days ({2. min per day) decreased the number of sperm in the semen by up to 80% on d 2., and the effect was completely reversed on d 144. Germ cells rely heavily on Sertoli cells for structural and nutritional support. Specialized junctions that play a pivotal role in spermatogenesis occur at sites of Sertoli-Sertoli and Sertoli-germ cell contact in the seminiferous epithelium. We demonstrated that expression of tight junction (TJ)-associated molecules, such as occludin and zonula occludens-1 (ZO-1), were greatly reduced 2.–48 h after heat treatment, while the permeability of the blood-testis barrier (BTB) was simultaneously increased, but recovered 10 d later. These results indicate a reversible disruption of the BTB associated with transient inductions of transforming growth factor (TGF) β2.and β{2.expression, p{2. mitogen-activated protein kinase and extracellular signal-regulated kinase activation, and concomitant loss of occludin and ZO-1. This suggests that expression of TJ-associated molecules and the BTB was reversibly perturbed by mild testicular hyperthermia, and that the heat-induced induction of TGF-β might be involved in downregulating TJ-associated proteins, leading to cell junction reduction. This review discusses the changes in total gene expression patterns after experimental cryptorchidism in adult mouse testes, and the cloning of several novel, physiologically significant spermatogenesis-specific genes.

关键词： cryptorchidism spermatogenesis apoptosis heat stress Sertoli cells blood-testis barrier tight junction

Role of ubiquitination in meiotic recombination repair

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Science China(Life Sciences) 2010年第4期53卷 447-454页

作者： CUI Li & LI Wei state key {2. of Reproductive Biology,{3., chinese academy of Sciences, beijing 100101, China 1. state key {2. of Reproductive Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China

Programmed and unprogrammed double-strand breaks (DSBs) often arise from such physiological requirements as meiotic recombination, and exogenous insults, such as ionizing radiation (IR). Due to deleterious impacts on genome stability, DSBs must be appropriately processed and repaired in a regulatory manner. Recent investigations have indicated that ubiquitination is a critical factor in DNA damage response and meiotic recombination repair. This review summarizes the effects of proteins and complexes associated with ubiquitination with regard to homologous recombination (HR)-dependent DSB repair.

关键词： ubiquitin meiosis homologous recombination DNA double-strand breaks

Effective solutions to a global 3. visual system in networking environments

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Science China Earth Sciences 2005年第11期48卷 2032-2039页

作者： ZHANG Liqiang1,2. ZHANG Yan3. YANG Chongjun2. LIU Suhong1, REN Yingchao2. RUI Xiaoping2.& LIU Donglin2.1. state {2. laboratory of Remote Sensing Sciences, School of Geography and Remote Sensing,{3. Normal University,{3. 100875, China 2. state {2. laboratory of Remote Sensing Sciences, institute of Remote Sensing Applications, chinese academy of Sciences,{3. 101001, China 3. institute of Geographical Sciences and Natural Resources Research, chinese academy of Sciences,{3. 101001, China 1. state key {2. of Remote Sensing Sciences School of Geography and Remote Sensing Beijing Normal University 100875 Beijing China 2. chinese academy of Sciences State Key Laboratory of Remote Sensing SciencesInstitute of Remote Sensing Applications 101001 Beijing China 3. institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 101001 Beijing China

The development of Web-based global 3. visual system has made progresses. However, there exist few mature and effective ways for managing, transmitting and visualizing massive spatial data. Based on the related work, the paper illustrates the ellipsoidal quadtree technique for rapid access multi-scale and multiple level geographical data, integrates the streaming with level-of-detail rendering method for transmitting the data on the network, and im-plements large-scale terrain surface simplification using M-band wavelet transforms and mul-tiresolution triangulations. We fulfil a web-based global terrain visual system using COM com-ponents on the basis of the above techniques. The system has a good prospect in the military simulation and city plans.

关键词： massive spatial data, streaming transmission, system architecture, M-band wavelet

Representation of microscale ocean wavenumber spectrum correct to the second order

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Science China Earth Sciences 2005年第4期48卷 549-554页

作者： YUAN Yeli2.& HUA Feng1,2.3.1. institute of Oceanology, {2. {2. of Sciences, Qingdao 2.6071, China 2. {3. laboratory of Marine Science and Numerical Modeling, state Oceanic Administration, Qingdao 2.6061, China 3. Graduate School of the {2. {2. of Sciences, beijing 10003., China 1. key laboratory of Marine Science and Numerical Modeling State Oceanic Administration 266061 Qingdao China 2. institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. Graduate School of the chinese {2. of Sciences 100039 Beijing China

In this paper, the analytical representations of four wave source functions in high-frequency spectrum range are given on the basis of ocean wave theory and dimensional analysis, and the perturbation method is used to solve the governing equations of ocean wave high-frequency spectrum on the basis of the temporally stationary and locally homogeneous scale relations of microscale wave. The microscale ocean wavenumber spectrum correct to the second order has an explicit structure, its first order part represents the equilibrium between dif- ferent source functions, and its second order part represents the contribution of microscale wave propagation.

关键词： temporally stationary and locally homogeneous, source function in high-frequency spectrum range, microscale ocean wavenumber spectrum.

Cotton pixel identification with CBERS-02.CCD data based on spectral knowledge

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Science China(Technological Sciences) 2005年第S2期48卷 129-144页

作者： LI Jing1,2.3. LIU Qinhuo1,3. LIU Qiang1, CHEN Liangfu1, BO Junhua3.& LI Shaokun3.1. state key laboratory of Remote Sensing Science, IRSA,{3. academy of Sciences, beijing 100101, China 2. Graduate University of{3. academy of Sciences, {12. 100049, China 3. The key Oasis Eco-agriculture laboratory of Xinjiang Production and Construction Corps, Shi Hezi 83.000, China 1. state key {2. of Remote Sensing Science IRSA Chinese Academy of Sciences 100101 Beijing China 2. Graduate University of chinese academy of Sciences 100049 Beijing China 3. The key Oasis Eco-agriculture {2. of Xinjiang Production and Construction Corps 832000 Shi Hezi China

In this paper the in-situ experiment data are collected from the Spectral Library to estimate the possible values of the primary structural parameters in each cotton growing season by statistics. Based on these values the spectra of the cotton major growing seasons were simulated and analyzed using the canopy reflectance model, SAILH. In this way we also simulated the cotton pixel spectra corresponding to CBERS-02.CCD and took them as the reference spectra for spectra fitting. Then No.143.Regiment of No.8 Agricultural Division of Xinjiang Production and Construction Corps (XPCC) was chosen as the study area, and two spectra fitting methods, Mahalanobis distance and spectra angle, were used to identify cotton pixel from CBERS-02.CCD image of the study area. At last we analyzed the effect of the calibration coefficients error on cotton identifying. The results showed that within 4% error the spectral angle classifier can still have a good performance.

关键词： CBERS-02 cotton pixel identification spectra fitting.

Possible mechanism of the effect of convection over Asian-Australian “land bridge” on the East Asian summer monsoon onset

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Science China Earth Sciences 2006年第11期49卷 1223-1232页

作者： HE Jinhai1, WEN Min2. DING Yihui3.& ZHANG Renhe2.1. Jiangsu key {2. of Meteorological Disaster (KLME), Nanjing institute of Meteorology, Nanjing University of Informa- tion Science and Technology, Nanjing 2.0044, China 2.{3. key {2. of Severe Weather (LaSW), chinese academy of Meteorological Sciences, beijing 100081, China 3. National Climate Center, chinese Meteorological Administration, beijing 100081, China 1. Jiangsu key laboratory of Meteorological Disaster (KLME) Nanjing Institute of Meteorology Nanjing University of Information Science and Technology Nanjing 210044 China 2. state key {2. of Severe Weather (LaSW) Chinese Academy of Meteorological Sciences Beijing 100081 China 3. National Climate Center Chinese Meteorological Administration Beijing 100081 China

The Asian-Australian “land bridge” is an area with the most vigorous convection in Asian monsoon region in boreal spring, where the onset and march of convection are well associated with the onset of East Asian summer monsoon. The convection occurs over Indo-China Peninsula as early as mid-April, which exerts critical impact on the evolution of monsoon circulation. Before mid-April there are primarily sensible heatings to the atmosphere over Indo-China Peninsula and Indian Peninsula, so the apparent heating ratios over them decrease with height. However, after mid-April it changes into latent heating over Indo-China Peninsula due to the onset of convection, and the apparent heating ratio increases with height in mid- and lower troposphere. The vertical distribution of heating ratio and its differences between Indo-China Peninsula and Indian Peninsula are the key factors leading to the splitting of boreal subtropical high belt over the Bay of Bengal. Such mechanism is strongly supported by the fact that the evolution of the vertical heating ratio gradient above Indo-China Peninsula leads that of 850 hPa vorticity over the Bay of Bengal. Convections over Indo-China Peninsula and its surrounding areas further increase after the splitting. Since then, there is a positive feedback lying among the convective heating, the eastward retreat of the subtropical high and the march of monsoon, which is a possible mechanism of the advance of summer monsoon and convection from Indo-China Peninsula to South China Sea.

关键词： Asian-Australian 'land bridge', tropical convection, Indo-China Peninsula, the splitting of boreal subtropical high belt, East Asian summer monsoon onset.

Simulation study of phase retrieval for hard X-ray in-line phase contrast imaging

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Science China(Physics,Mechanics & Astronomy) 2005年第4期48卷 450-458页

作者： YU Bin1,2. PENG Xiang1,2. TIAN Jindong1, NIU Hanben1, DIAO Luhong3.& LI Hua3.1. {2. laboratory of Optoelectronic Devices and Systems of Ministry of Education, institute of Optoelec- tronics, Shenzhen University, Shenzhen 518060, China 2.{3. {2. laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 3.0072.China 3. {2. laboratory of Intelligent Information Processing, institute of Computing Technology, chinese academy of Sciences, beijing 100080,China 1. key laboratory of Optoelectronic Devices and Systems of Ministry of Education Institute of Optoelectronics Shenzhen University 518060 Shenzhen China 2. state key {2. of Precision Measuring Technology and Instruments Tianjin University 300072 Tianjin China 3. key {2. of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences 100080 Beijing China

Two algorithms for the phase retrieval of hard X-ray in-line phase contrast imaging are presented. One is referred to as Iterative Angular Spectrum Algorithm (IASA) and the other is a hybrid algorithm that combines IASA with TIE (transport of intensity equation). The calculations of the algorithms are based on free space propagation of the angular spectrum. The new approaches are demonstrated with numerical simulations. Comparisons with other phase retrieval algorithms are also performed. It is shown that the phase retrieval method combining the IASA and TIE is a promising technique for the application of hard X-ray phase contrast imaging.

关键词： X-ray optics, phase contrast imaging, phase retrieval, angular spectrum, hard X-ray.