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Role of oxyR from Sinorhizobium meliloti in Regulating the Expression of Catalases

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Acta Biochimica et Biophysica Sinica 2005年第6期37卷 421-428页

作者： Li EUO~(1.3) Ming-Sheng QI~(1.3) Shi-Yi YAO~2 Hai-Ping CHENG~2 Jia-Bi ZHU~1 Guan-Qiao YU~1 1 National Laboratory of Plant Molecular Genetics, Institute of Plant Physiology and Ecology, shanghai Institutes for Biological sciences.chinese academy of sciences, shanghai 200032. china 2 Biological sciences Department, Lehman College, the City University of New York, Bronx, NY 10468. USA, 3 graduate school of the chinese academy of sciences, shanghai 200032. china NationalLaboratoryofPlantMolecularGenetics InstituteofPlantPhysiologyandEcologyShanghaiInstitutesforBiologi

The process of symbiotic nitrogen fixation results in the generation of reactive oxygen speciessuch as the superoxide anion（O2-）and hydrogen peroxide（H2O2）.The response of rhizobia to these toxicoxygen species is an important factor in nodulation and nitrogen *** Sinorhizobium meliloti,oneoxyR homologue and three catalase genes,katA,katB,and katC were detected by sequence *** gene is located next to and divergently from katA on the *** investigate the possible rolesof oxyR in regulating the expression of catalases at the transcriptional level in ***,an insertion mutantof this gene was *** mutant was more sensitive and less adaptive to H2O2than the wild typestrain,and total catalase/peroxidase activity was reduced approximately fourfold with the OxyR mutationrelative to *** activities of KatA and KatB and the expression of katA::lacZ and katB::lacZ promoterfusions were increased in the mutant strain compared with the parental strain grown in the absence of H2O2,indicating that katA and katB are repressed by ***,when exposed to H2O2,katA expressionwas also increased in both *** and Escherichia *** exposed to H2O2,OxyR is convertedfrom a reduced to an oxidized form in *** concluded that the reduced form of OxyR functions as arepressor of katA and katB ***,in the presence of H2O2,reduced OxyR is converted to theoxidized form of OxyR that then results in increased katA *** further showed that oxyR expressionis autoregulated via negative feedback.

关键词： Sinorhizobium meliloti OxyR catalase katA H2O2

Development of a Wire Driven Robot for Grinding with Stiffness Adapted

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厦门大学学报（自然科学版） 2002年第S1期41卷 81-82页

作者： ZHANG Bo 1,2, ZHAO Ming-yang 2 (1. graduate school of the chinese academy of sciences, Beijing 100039 , china 2. Robotics Laboratory, Shenyang Institute of Automation, chinese academy of S ciences, Shenyang 110016, china)

Along with development of new design and machining me thod production with more complex surface can be manufactured. Researching on th e new equipment used for surface disposal has become the important matter. Grind ing and polishing are a common surface processing method. A new type wire driven parallel robot used for grinding processing is proposed in this paper. Wire driven parallel robot is developed from parallel robot and serial wire driven r obot. Steel wire is used to replace the leg of parallel robot. Compared with par allel robot, this kind of robot has lager workspace, lower weight, higher rigidi ty and higher load/deadweight ratio. And the stiffness of robot is controlled by changing the tension of wire. The robot proposed in this paper has three DOF. T he moving part is driven by four wires, three of them are used to drive and the rest to keep them tension, with a restraining machine. The position sensors are installed in restraining machine. The position of terminating of end-effecter c an be ascertained in the space. The tension sensors are installed in each wire t o form force feedback system. By changing the tension the force on the workpiece can be controlled. Also the stiffness of robot can be adjusted.

关键词： wire driven parallel robot stiffness control

Convergence analysis of the adaptive finite element method with the red-green refinement

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Science china Mathematics 2010年第2期53卷 499-512页

作者： ZHAO XuYing 1, 3 , HU Jun 2,? & SHI ZhongCi 1 1 State Key Laboratory of Scientific and Engineering Computing, Institute of Computational Mathematics and Scientific/Engineering Computing, academy of Mathematics and Systems Science, chinese academy of sciences, Beijing 100190, china 2 Key Laboratory of Mathematics and Applied Mathematics (Peking University), Ministry of Education and school of Mathematical sciences, Peking University, Beijing 100871, china 3 graduate University of chinese academy of sciences, Beijing 100190, china 1. State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China3. Graduate University of Chinese Academy of Sciences Beijing 100190 China2. Key Laboratory of Mathematics and Applied Mathematics (Peking University) Ministry of Education and School of Mathematical Sciences Peking University Beijing 100871 China

In this paper, we analyze the convergence of the adaptive conforming P 1 element method with the red-green refinement. Since the mesh after refining is not nested into the one before, the Galerkin-orthogonality does not hold for this case. To overcome such a difficulty, we prove some quasi-orthogonality instead under some mild condition on the initial mesh (Condition A). Consequently, we show convergence of the adaptive method by establishing the reduction of some total error. To weaken the condition on the initial mesh, we propose a modified red-green refinement and prove the convergence of the associated adaptive method under a much weaker condition on the initial mesh (Condition B).

关键词： red-green refinement adaptive finite element method convergence non-nested local refinement

POSITIVE SOLUTIONS FOR WEAKLY COUPLED NONLINEAR ELLIPTIC SYSTEMS

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Acta Mathematica Scientia 2010年第5期30卷 1577-1592页

作者：龙静杨健夫 Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences graduate school Chinese Academy of Sciences Department of Mathematics Jiangxi Normal University

In this article, we consider the existence of positive solutions for weakly coupled nonlinear elliptic systems {-△u＋u=（1＋a（x））｜u｜P-1u＋μ｜u｜a-2u｜v｜β＋λv in Rn,-△u＋u=（1＋b（x））｜v｜p-1v＋μ｜u｜a｜v｜β-2v＋λu in Rn To find nontrivial solutions, we first investigate autonomous systems. In this case, results of bifurcation from semi-trivial solutions are obtained by the implicit function theorem. Next, the existence of positive solutions of problem （0.1） is obtained by variational methods.

关键词： Elliptic system in RN positive solution bifurcation variational method

Sporopollen analysis of Core B10 in the southern Yellow Sea and the reflected characteristics of climate changes

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chinese Science Bulletin 2003年第B06期48卷 42-48页

作者： FU Mingzuo~(1,2,3), LI Zhen~1, XU Xiaowei~1 & SHl Xuefa~1 1. Key Laboratory of Marine Sedimentology and Environmental Geology, First institute of Oceanography. State Oceanic Administration, Qingdao 266061. china 2. Institute of Oceanology, chinese academy of sciences, Qingdao 266071. china 3. graduate school, chinese academy of sciences, Beijing 100039. china 1. Key Laboratory of Marine Sedimentology and Environmental Geology First institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. Institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. graduate school Chinese Academy of Sciences 100039 Beijing China

Eight sporopollen zones have been divided based on the results of high-resolution sporopollen analysis of Core B10 in the southern Yellow Sea. Based on the results along with ^14C datings and the subbottom profiling data,climatic and environmental changes since the last stage of late Pleistocene are discussed. The main conclusions are drawn as follows: (1) the vegetation evolved in the process of coniferous forest-grassland containing broad-leaved trees→coniferous and broad-leaved mixed forest→coniferons and broad-leaved mixed forest-grassland prevailed by coniferous trees→coniferous and broad-leaved mixed forest-grassland containing evergreen broad-leaved trees→coniferons and broad-leaved mixed forest-grassland prevailed by broadleaved trees→deciduous broad-leaved forest-meadow containing evergreen broad-leaved trees→coniferous and broadleaved mixed forest-grassland prevailed by broad-leaved trees→coniferous and broad-leaved mixed forest containing evergreen broad-leaved trees; (2) eight stages of climate changes are identified as the cold and dry stage, the temperate and wet stage, the cold and dry stage, the warm and dry stage, the temperate and wet stage, the hot and dry stage, the temperate and dry stage, then the warm and dry stage in turn; (3) the sedimentary environment developed from land,to littoral zone, to land again, then to shore-neritic zone; and (4) the Yellow Sea Warm Current formed during early-Holocene rather than Atlantic stage.

关键词：中国黄海气候变化碳14年代测定底基压型数据更新世沉积环境大西洋

The Impacts of Permafrost Change on NPP and Implications:A Case of the Source Regions of Yangtze and Yellow Rivers

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Journal of Mountain Science 2011年第3期8卷 437-447页

作者： FANG Yiping QIN Dahe DING Yongjian YANG Jianping XU Keyan Institute of Mountain Hazards & Environment Chinese Academy of Sciences Chengdu 610041 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China graduate school of chinese academy of sciences Beijing 100049 China

This paper studies the relationship between net primary productivity (NPP) and annual average air temperature (GT) at 0cm above ground in permafrost regions by using revised Chikugo NPP model,cubic spline interpolating functions,and non-linear regression *** source regions of the Yangtze and Yellow Rivers were selected as the research *** illustrate that:(1) There is significant non-linear relationship between NPP and GT in various typical years;(2) The maximum value of NPP is 6.17,5.87,7.73,and 5.41 DM·t·hm-2 ·a-1 respectively,and the corresponding GT is 7.1,10.0,21.2,and 8.9 o C respectively in 1980,1990,2000 and 2007;(3) In 1980,the sensitivity of NPP to GT is higher than in 1990,2000 and *** tendency shows that the NPP presents change from fluctuation to an adaptation process over time;(4) During 1980～2007,the accumulated NPP was reduced to 8.05,and the corresponding carrying capacity of theoretical livestock reduced by 11%;(5) The shape of the demonstration region of ecological compensation system,livelihood support system,and science appraisal system in the source regions of Yangtze and Yellow Rivers are an important research for increasing the adaptation capacity and balancing protection and development.

关键词： The source regions of Yangtze and Yellow Rivers Permafrost Ground temperature (GT) Net primary productivity (NPP) Policy adaptation

Differential expression analysis of Liprin-α2 in hibernating bat (Rhinolophus ferrumequinum)

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Progress in Natural Science:Materials International 2008年第1期18卷 27-32页

作者： Lihong Yuan a,b,c, Xueguo Zuo a, Jinping Chen d, Benfu Lin e, Junpeng Zhang b, Min Sun e, Shuyi Zhang a,* a school of Life Science, East china Normal University, shanghai 200062, china b Institute of Zoology, chinese academy of sciences, Beijing 100080, china c graduate University of chinese academy of sciences, Beijing 100080, china d Guangdong Entomological Institute, Guangzhou 510260, china e Guangzhou Institute of Biomedicine and Health, chinese academy of sciences, Guangzhou 510663, china school of Life Science East China Normal University Shanghai 200062 China Institute of Zoology Chinese Academy of Sciences Beijing 100080 China graduate University of chinese academy of sciences Beijing 100080 China Guangdong Entomological Institute Guangzhou 510260 China Guangzhou Institute of Biomedicine and Health Chinese Academy of Sciences Guangzhou 510663 China

A PCR-based subtractive hybridization technique was used to identify genes up-regulated in the hibernating bat brain to explore the molecular mechanism of hibernation. Three genes, Liprin-a2, PTP4A2 and CAMKKb were difierentially expressed in hibernating bat brain tissue compared to active bat brain tissue. One of them, Liprin-a2, which has recently been shown to have the key function in the organization of presynaptic and postsynaptic multiprotein complexes was studied in detail. We demonstrated that the expression level of Liprin-a2 was up-regulated almost 4-fold in hibernating bat brains by RT-PCR compared to levels in active bats. The difierential expression pattern of Liprin-a2 was also detected in muscle, fat, brain and heart tissue of hibernating bats by real-time quantitative PCR. The result indicated that Liprin-a2 was over-expressed in brain and heart tissue and down-regulated in muscle and fat. In brain tissue of hibernating bats, Liprin-a2 expression was statistically significantly higher than in brain tissue of active controls (P = 0.029). The precise control of transcriptional level and the distinctively difierential expression pattern of Liprin-a2 in difierent organs during circ- annual hibernation may have important physiological significance, not only in maintaining normal function of many key organs but also in effectively conserving limited energy resources without physiological damage.

关键词： Bat Differential expression Hibernation Liprin-a2

Experimental measurement of the electrical conductivity of single crystal olivine at high temperature and high pressure under different oxygen fugacities

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Progress in Natural Science:Materials International 2006年第4期16卷 387-393页

作者： DAI Lidong, LI Heping, LIU Congqiang, CUI Tongdi, SHAN Shuangming, YANG Changjun, LIU Qingyou and DENG Heming Laboratory of the Earth’s Interior Materials and Fluid Geochemistry, Institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china graduate school of the chinese academy of sciences, Beijing 100039, china Institute of Geochemistry, chinese academy of sciences, Guiyang 550002, china Guizhou University, Guiyang 550004, china Laboratory of the Earth's Interior Materials and Fluid Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China graduate school of the chinese academy of sciences Beijing 100039 China Institute of Geochemistry chinese academy of sciences Guiyang 550002 China Guizhou University Guiyang 550004 China

At 1.0-4.0 GPa and 1123-1473 K and under oxygen fugacity-controlled conditions (Ni + NiO, Fe + Fe3O4, Fe + FeO and Mo+ M0O2 buffers), a YJ-3000t Model six-anvil solid high-pressure apparatus and a Sarltron-1260 Impedance/Gain-Phase analyzer were employed to conduct an in situ measurement of the electrical conductivity of single crystal olivine. Experimental results showed that: (1) within the range of experimentally selected frequencies (103-106 Hz), the electrical conductivity of the sample is of great dependence on the frequency; (2) with the rise of temperature ( T), the electrical conductivity (σ) will increase, and the Arrenhius linear relationship is established between lgσ and 1/T; (3) under the control of oxygen buffer Fe+ Fe3O4, with the rise of pressure, the electrical conductivity tends to decrease whereas the activation enthalpy and independent-of-temperature preexponential factor tend to increase, with the activation energy and activation volume of the sample estimated at (1. 25 ± 0.08) eV and (0.105 ±0.025) cm3/mol, respectively; (4) under given pressure and temperature conditions, the electrical conductivity tends to increase whereas the activation energy tends to decrease with increasing oxygen fugacity; and ( 5) the mechanism of electrical conduction of small polarons can provide insight into the behavior of electrical conduction of olivine under high pressure and high temperature.

关键词： olivine high temperature and high pressure electrical conductivity oxygen fugacity small polaron.

Identification and removal of block ambiguities in sea surface wind field with scatterometers

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Science china Earth sciences 2009年第2期52卷 242-249页

作者： CHEN KeHai1,2, XIE XueTong3 & FANG Yu4 1 South china Sea Institute of Oceanology, chinese academy of sciences, Guangzhou 510301, china 2 graduate University of chinese academy of sciences, Beijing 100049, china 3 school of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073, china 4 The Institute of Remote Sensing and GIS, Peking University, Beijing 100871, china 1. South china Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China 2. graduate University of chinese academy of sciences Beijing 100049 China 3. school of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China 4. The Institute of Remote Sensing and GIS Peking University Beijing 100871 China

The solution of the current wind retrieval algorithm for scatterometers has several wind vector ambi-guities, due to the bi-harmonic relationship between normalized backscattering cross section and the relative wind direction and the existence of the measurement error. In order to remove the ambiguities for a unique wind field, a circular median filter approach (CMF) is usually adopted. But under the con-dition for clustering distribution of the false ambiguities in some local areas, the CMF fails and thus engenders block ambiguities, which degrade the precision of the retrieved wind field. For such a situation, a technique of identification and removal of the block ambiguities is presented to further optimize the retrieved wind field after CMF. It is demonstrated in experiment that this technique can identify and remove most of the block ambiguities.

关键词： scatterometer block ambiguity identification and removal