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The effects of proteasome inhibitor lactacystin on mouse oocyte meiosis and first cleavage

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Science China(Life Sciences) 2005年第3期48卷 287-294页

作者： TAN Xin 1,3., PENG An 2., WANG Yongchao 2.& TANG Zuoqing 3.1. School of Life Sciences and {2., beijing Institute of {2., beijing 100081, China 2. College of Life Sciences, beijing Normal University, beijing 100875, China 3. College of Basic Medicine, Capital University of Medical Sciences, beijing 100054, China 1. School of Life Sciences and technology Beijing Institute of Technology 100081 Beijing China 2. College of Basic Medicine Capital University of Medical Sciences 100054 Beijing China 3. College of Life Sciences Beijing Normal University 100875 Beijing China

In order to study the effects of ubiquitin-proteasome pathway (UPP) on mouse oo- cyte meiosis and cleavage, oocytes undergoing maturation and parthenogenetic activation and 1-cell embryos were treated with lactacystin, a specific inhibitor of proteasome. The results indi- cated that the rate of GVBD was not influenced by the treatment, but polar body extrusion, par- thenogenesis and first cleavage were inhibited. Immunofluorescent staining using anti β-tubulin antibody indicated that the continuous treatment of lactacystin from GV stage disorganized microtubules and spindle assembly. When metaphase stage oocytes were treated with the drug, the already formed spindle structure was not affected , but the oocytes were arrested at meta- phases. The 1-cell embryos were arrested at interphase or metaphase of first mitosis when they were incubated in the drug. Proteasome regulatory subunit PA700 was located in the spindle region, as indicated by immunofluorescence. These results suggest that UPP has effects on the process of oocyte meiosis and early cleavage in many aspects, including normal organization of spindle at prophase and segregation of chromosomes at anaphase for normal meiosis.

关键词： proteasome, oocyte, meiosis, cleavage.

Study on the coating of nano-scale SiO_2.film on the surface of nanocrystalline Mg-Al layered double hydroxides

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Science China Chemistry 2005年第2期48卷 107-114页

作者： ZHANG Zejiang1,2.3. MEI Xiujuan2. XU Chenghua1 & QIU Fali1 1. Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China 2. Sichuan Fire research Institute of Public Security Ministry, Chengdu 61183., China 3. Graduate School of the Chinese Academy of Sciences, beijing 10003., China Correspondence should be addressed to Zhang Zejiang (email: zzjzzjzz@***) 1. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. Sichuan Fire research Institute of Public Security Ministry 611830 Chengdu China 3. Graduate School of the Chinese Academy of Sciences 100039 Beijing China

The coating process of a nano-scale SiO2.film on the nanocrystalline Mg-Al layered double hydroxides via a sol-gel process was investigated. The uniform and dense SiO2.ilm with a thickness of about 5 nm on the nano-LDHs particles was characterized by the solubility test in the dilute HNO3.or HCl acid, TEM and FT-IR, XRD, TG and DSC. The chemical shifts of binding en- ergies of Al 2., Mg 2., Si 2. and O 1s on the coated particles indicate that the coating of the SiO2.nano-film on the surface of the nano-LDHs proceeds through the formation of Mg-O-Si and Al-O-Si bonds. The thermal analysis shows that both the SiO2.coated nano-LDHs and the nano-LDHs have a similar mass loss process, in which there are three obvious stages of mass loss in the temperature range of 40—700℃. Furthermore, the more the coatedamount of SiO2.n the surface of the nano-LDHs is, the less the mass loss of the samples is at 700℃.The nano- LDHs have two obvious endothermic peaks at 2.4.67℃ and 43..13., whose corresponding heat absorption capacities are 412.2. J/g and 3.6.3. J/g, respectively. In contrast, the coated nano-LDHs have only one endothermic peak at 2.3.60℃ with a heat absorption capacity of 2.1.2. J/g.

关键词： layered double hydroxides, nanocrystalline, silica, coating.

Validity of the Bouchet's complementary relationship at 102.observatories across China

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Science China Earth Sciences 2009年第5期52卷 708-713页

作者： YU JingJie1,2.ZHANG YongQiang3.LIU ChangMing1,2.1 Institute of Geographic Sciences and Natural Resources research,Chinese Academy of Sciences,{2. 100101,China 2.Key Laboratory of Water Cycle and Related Land Surface Processes,Chinese Academy of Sciences,{2. 100101,China 3.CSIRO Land and Water,PO Box 1666,Canberra ACT 2.01,Australia Institute of Geographic Sciences and Natural Resources research Chinese Academy of Sciences Beijing 100101 China Key Laboratory of Water Cycle and Related Land Surface Processes Chinese Academy of Sciences Beijing 100101 China CSIRO La

Bouchet in 1963.hypothesized that for large homogeneous land surface with minimum advection of heat and moisture,there exists a 1:1 complementary relationship of potential and actual evaporation coupled through land-atmosphere *** complementary relationship has been widely used to estimate regional actual evaporation and explain the pan evaporation *** examine the standardized potential evaporation(potential evaporation divided by wet environment evaporation) at 102.observatories at different elevations across ***,the relationship is appropriate at the low elevations(<1000 m).With the increase of elevation,vapor transfer power becomes much less than radiation energy budget because of lower vapor pressure deficit and stronger global solar *** a result,at the high elevations(over 1000 m),the excess energy resulted by limited moisture availability is not enough to be converted into drying power of the *** result suggests that the complementary relationship is asymmetric at the high elevations.

关键词： evaporation complementary relationship elevation China

Climate change tendency and grassland vegetation response during the growth season in Three-River Source Region

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Science China Earth Sciences 2010年第10期53卷 1506-1512页

作者： QIAN Shuan1,FU Yang2.& PAN FeiFei3.1 National Meteorological Center,beijing 100081,China 2.Qinghai Meteorological {2. Institute,Xining 810001,China 3.Department of Geography,University of North Texas,Denton,TX 762.3.USA 1. National Meteorological Center Beijing 100081 China2. Qinghai Meteorological Research Institute Xining 810001 China3. Department of Geography University of North Texas Denton TX 76203 USA

Climate change,climate suitablity change for grassland vegetation,and grassland response to climate change during the growth season are studied systematically by using meteorological data of temperature,precipitation,and length of sunlight from 1961 to 2.07,NOAA/AVHRR NDVI from 1982.to 2.06,and observations of grass height,biomass,and coverage in enclosed grassland from 1994 to *** models are developed to evaluate climate change and the climatic suitability of grassland vegetation *** temperature,accumulative precipitation,and length of sunlight during the growth season increased from 1961 to 2.07 at rates of 0.2.°C/10 yr,2.3. mm/10 yr,and 2.81 h/10 yr,*** increase rates of ave-rage temperature between April and May,and between June and August are 0.17 and 0.3.°C/10 yr;accumulative rainfall between April and May increased at a rate of 2.80 mm/10 yr,and accumulative rainfall between June and August decreased at a rate of 0.3. mm/10 yr;the increase rates of accumulative length of sunlight between April and May,and between June and August are 2.15 and 1.2.h/10 *** climatic suitability of grassland vegetation growth showed an increasing trend,and the increase rate between April and May is greater than that between June and *** NDVI observations from 1982.to 2.06 and measurements of grass height,dry biomass,and coverage from 1994 to 2.06 show that the climate change has resulted in an increase in plant productivity of the grassland in Three-River Source *** some protection measures are taken as soon as possible,the deteriorated grassland in Three-River Source Region can recover.

关键词： climate change climate suitability change grassland vegetation Three-River Source Region

The Microstructure Mechanical Property Characteristic of 1Cr17/9Cr18MoV Multilayered Plates

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Journal of Iron and Steel research International 2011年第S1期18卷 933-935页

作者： XIE Guo-liang 1,WANG Yan-lin 2.LIU Jing 1,HAN Jing-tao 1,GAO Gang 1 (1.School of Materials Science and Engineering,University of Science and technology beijing,beijing 100083.China 2.Fangda {3. Steel technology Co.,Ltd,Nanchang 3.0012.China) Univ Sci & Technol beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Fangda special Steel Technol Co Ltd Nanchang 330012 Peoples R China

A multilayered plate,containing two different steel,1Cr17 and 9Cr18MoV are *** microstructures of both materials and the transition zone of interfaces are investigated by SEM and *** point bending tests are employed to determine its mechanical *** multilayered composite shows a different mechanical property:a much lager bending defection than that of 9Cr18MoV material and a much higher strength than that of 1Cr17 material.

关键词： multilayered plate 1Cr17/9Cr18MoV microstructures mechanical property

Symbolic Computation Study of (2.1)-Dimensional Dispersive Long Wave Equations

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Communications in Theoretical Physics 2006年第8期46卷 199-202页

作者： LU Zhuo-Sheng~(1,2.+) and XIE Fu-Ding~(2.3. ~1School of Science, beijing University of Post and Telecommunications, beijing 100876, China ~2.ey Laboratory of Mathematics Mechanization, Academy of Mathematics and System Sciences, the Chinese Academy of Sciences, beijing 100080, China ~3.epartment of Computer Science, Liaoning Normal University, Dalian 11602., China Department of Otolaryngology University Hospital VU P.O. Box 7057 1007 MB Amsterdam The Netherlands School of Science Beijing University of Post and Telecommunications Beijing 100876 China

Seeking exact analytical solutions of nonlinear evolution equations is of fundamental importance in mathematical physics. In this paper, based on a constructive algorithm and symbolic computation, abundant new exact solutions of the (2.1)-dimensional dispersive long wave equations are obtained, among which there are soliton-like solutions, mult-soliton-like solutions and formal periodic solutions, etc. Certain special solutions are considered and some interesting localized structures are revealed.

关键词： dispersive long wave equations symbolic computation exact solution localized structure

The correlation of multi-angle thermal infrared data and the choice of optimal view angles

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Science China Earth Sciences 2004年第6期47卷 570-576页

作者： FAN Wenjie1 & XU Xiru1,2.1.Institute of Remote Sensing and GIS of Peking University,beijing 100871,China 2.Center of Remote Sensing and GIS of beijing Normal University,beijing 100875,China 1. Institute of Remote Sensing and GIS of Peking University 100871 Beijing China 2. Center of Remote Sensing and GIS of beijing Normal University 100875 Beijing China

Based on the matrix formula of thermal infrared radiant system, the components temperature can be retrieved by the inversive matrix. Around the stability problem of retrieved result, the research work we did was focused on (i) the correlation of (wk,j) which is the key to affect the retrieval accuracy, (ii) a general method which can help us find the number of retrievable parameters and evaluate the retrieval error before its performance, (iii) the choice of “optimal viewing angle group” based on the formula of absolute error propagation. The row winter wheat field was chosen as an example. The results can provide a theoretical basis for multi-angle thermal infrared remote sensing and components temperature retrieval.

关键词： components temperature retrieval, correlation, number of retrievable parameters, optimal viewing angle group.

A new orthogonality relationship for orthotropic thin plate theory and its variational principle

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Science China(Physics,Mechanics & Astronomy) 2005年第3期48卷 371-380页

作者： LUO Jianhui 1 , LONG Yuqiu 2.& LIU Guangdong 1 1. College of Civil Engineering, Hunan University, Changsha 410082. China 2. Department of Civil Engineering, Tsinghua University, beijing 100084, China 1. College of Civil Engineering Hunan University 410082 Changsha China 2. Department of Civil Engineering Tsinghua University 100084 Beijing China

The thought how dual vectors are constructed in a new orthogonality relationship for theory of elasticity is generalized into orthotropic thin plate bending problems by using the analogy theory between plane elasticity problems and plate bending problems. Dual differential equations are directly obtained by using a mixed variables method. A dual differential matrix to be derived possesses a peculiarity of which principal diagonal sub-matrixes are zero matrixes. Two independently and symmetrically orthogonality sub-relationships are discovered. By using the integral form for elastic bending theory of orthotropic thin plate the orthogonality relationship is demonstrated. By selecting felicitous dual vectors a new orthogonality relationship for theory of elasticity can be generalized into elastic bending theory of orthotropic thin plate. By using the integral form a variational principle which is relative to differential form and a whole function expression are proposed.

关键词： theory of elasticity, thin plate theory, dual vectors, orthogonality relationship, orthotropic, variational principle.

Analysis of moment invariants under general linear transformation

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Science China(Information Sciences) 2010年第7期53卷 1305-1311页

作者： DIAO LuHong1, LI Hua2. ZHANG Sen1 & LIU Lei1 1College of Applied Sciences, beijing University of technology, beijing 10012., China 2.ational Center of Intelligent Computing, Institute of Computing technology, Chinese Academy of Science, beijing 100080, China 1. College of Applied Sciences Beijing University of Technology Beijing 100124 China2. National Center of Intelligent Computing Institute of Computing Technology Chinese Academy of Science Beijing 100080 China

This paper presents the necessary and sufficient condition of moment invariants under general linear transformation. Based on this condition, arbitrary order and dimensional moment invariant sets can be constructed. D... 详细信息

关键词： moment invariants independence linear transformation