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Ion channels in neuronal survival

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Science china(Life sciences) 2010年第3期53卷 342-347页

作者： WANG YiZheng & XU TianLe Institute of Neuroscience and State key laboratory of Neuroscience,Shanghai Institutes for Biological {2.,chinese academy of {2.,Shanghai 2.0031,china 1. Institute of Neuroscience and State key laboratory of Neuroscience Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200031 China

The study of ion channels represents one of the most active fields in neuroscience research in *** the last 10 years,active research in various chinese neuroscience institutions has sought to understand the mechanisms responsible for sensory processing,neural development and neurogenesis,neural plasticity,as well as *** addition,extensive studies have been directed to measure ion channel activity,structure-function relationships,as well as many other biophysical and biochemical *** review focuses on the progress achieved in the investigation of ion channels in neuronal survival during the past 10 years in {2..

关键词： ion channels neuronal survival and ischemia.

Photogeneration of the free radicals and singlet oxygen by chrysophanol from rheum

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Science china Chemistry 2004年第5期47卷 381-387页

作者： RAO Jing1,2. XIE Jie1, ZHAO Jingquan1 & ZHU Teng2.1. key laboratory of Photochemistry, Center for Molecular Science, Institute of Chemistry, The {2. academy of sciences, Beijing 100080, china 2. University of Science and Technology Beijing, Beijing 10083, china 1. key laboratory of Photochemistry Center for Molecular Science Institute of Chemistry The Chinese Academy of Sciences 100080 Beijing China 2. University of Science and Technology Beijing 10083 Beijing China

In the current work, chryosphanol (MHAQ) was isolated and purified from rheum, and the photosensitization activities were studied. In nitrogen-saturated DMSO solution, irradia- tion of chryosphanol (MHAQ) with visible light (>430 nm) produced the semiquinone radical anions (MHAQ??), which was intensified significantly by an electron donor NADH, suggesting electron transfer between the excited and ground state photosensitizer molecules. In an air-saturated DMSO solution, superoxide radical anions (O2.), trapped by DMPO, were detected. ?? It was proved that O2.was not originated from the singlet oxygen (1O2. but dependent on DMPO, ?? chrysophanol, oxygen and the irradiation time. The singlet oxygen and OH could also be pro- ? duced by the photosensitization of the photosensitizer. These suggest that chrysophanol pos- sesses the photosensitization activity via Type I mechanism and Type II mechanism. To evaluate the photosensitization activities of MHAQ, emodin and mixed anthraquinone derivatives ex- tracted from rheum, the relative productivities of O2.were estimated to be 1.8, 1.1 and 1.0 re- ?? spectively and the quantum yields for singlet oxygen to be 0.36, 0.53 and 0.14 respectively. Therefore, these low-cost pigments may be potentially used as phototherapeutic medicine for some kind of vascular diseases or photo-activated pesticides.

关键词： chrysophanol, ESR, semiquinone radical anions, superoxide radical anions, hydroxyl radical, singlet oxygen.

Optimization of mathematical models for thematic maps

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Science china(Technological sciences) 2010年第S1期53卷 15-24页

作者： QI QingWen1,ZHANG An1,JIANG LiLi1,ZOU XiuPing2.XU Li3 & CHENG Xi1,4 1 Institute of Geographical sciences and Natural Resources Research,chinese {2. of sciences,Beijing 100101,china 2.Institute of Policy and Management,chinese {2. of sciences,Beijing 100080,china 3 Taishan University,Taian 2.102.,china 4 Graduate University of chinese {2. of sciences,Beijing 100049,china chinese Acad Sci Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China chinese Acad Sci Inst Policy & Management Beijing 100080 Peoples R China Taishan Univ Tai An 271021 Shandong Peoples R China chinese Acad Sci Grad Univ Beijing 100049 Peoples R China

The thematic map is a major class of maps designed to demonstrate particular features or concepts,functioning as an indispensable tool in geographical *** process of thematic mapping is one into which geographical research goes deeply and *** key activity and course of thematic map production is the use of mathematical models to create thematic data ***,the selection and optimization of mathematical models is in the forefront of thematic map *** theoretical foundations,mechanisms and methods of mathematical model optimization are expounded in this paper,including two approaches,the phase by phase mode and the multi-aim scheme balance *** studies in eco-environment mapping and emergency mapping are described and analyzed,with a hierarchical analysis method being used in the model optimization for eco-environment fragility and sensitivity assessment mapping in Beibuwan (Guangxi) District,the dynamic system (DS) method being used in the model optimization for ecological security adjustment mapping in Xishuang Banna,Yunnan province,and the multi-phase mode being used in the models for forest fire and infectious diseases mapping.

关键词： thematic map mathematic model optimization

Panel positioning error and support mechanism for a 30-m THz radio telescope

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Research in Astronomy and Astrophysics 2011年第6期11卷 725-736页

作者： De-Hua Yang Daniel Okoh Guo-Hua Zhou Ai-Hua Li Guo-Ping Jing-Quan Cheng national astronomical {2. /Nanjing Institute of astronomical Optics ＆ Technology Chinese Academy of SciencesNanjing 210042China key laboratory of {2. Optics ＆ Technology Nanjing Institute of Astronomical Optics ＆ TechnologyChinese Academy of SciencesNanjing 210042China Centre for Basic Space Science National Space Research and Development AgencyUniversity of NigeriaNsukka 410002Nigeria national Radio Astronomy Observatory CharlottesvilleVA 22903USA

A 30-m TeraHertz（THz） radio telescope is proposed to operate at 2.0 μm with an active primary *** paper presents sensitivity analysis of active surface panel positioning errors with optical performance in terms of the Strehl *** on Ruze＇s surface error theory and using a Monte Carlo simulation,the effects of six rigid panel positioning errors,such as piston,tip,tilt,radial,azimuthal and twist displacements,were directly *** optical performance of the telescope was then evaluated using the standard Strehl *** graphically illustrated the various panel error effects by presenting simulations of complete ensembles of full reflector surface errors for the six different rigid panel positioning *** of the panel error sensitivity analysis revealed that the piston error and tilt/tip errors are dominant while the other rigid errors are much less ***,as indicated by the results,we conceived of an alternative Master-Slave Concept-based（MSC-based） active surface by implementating a special Series-Parallel Concept-based（SPC-based） hexapod as the active panel support mechanism.A new 30-m active reflector based on the two concepts was demonstrated to achieve correction for all the six rigid panel positioning errors in an economically feasible way.

关键词： telescopes-methods:data analysis-methods:statistical-techniques:miscellaneous

Present status and development on biological nitrogen fixation research in china

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chinese Science Bulletin 2003年第10期48卷 954-960页

作者： SHEN Shihua & JING Yuxiang key laboratory of Photosynthesis and Plant-Environment MolecularPhysiology, Institute of Botany, {2. academy of sciences, Beijing 100093, china key laboratory of Photosynthesis and Plant-Environment Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China

This presentation introduces the advances inbiological nitrogen fixation research abroad, in particular,describes the great progress and achievements on itsresearch in china as follows: collection of rhizobial resources and establishment of the largest database of Rhizobium inchina, correction and development of Rhizobium taxonomy in inter{2.; discovery of a couple of nif genes,identification and unification of linkage among the nif gene operons of Klebsiella pneumoniae, finding of regulative mechanism of positive regulation nif gene and its sensitivity to oxygen, temperature; finding of the activity of nodulation gene nodD3 product in Sinorhizobium meliloti which is notcontrolled by flavonoid produced from its host alfalfa;finding of the association between expression of genes coding the products for carbon utilization and nitrogen metabolism and their regulations; chemical synthesis of nodulationfactor of Sinorhizobium meliloti; constructions of engineered nitrogen fixers and utilization in practice based on theresearch of gene expression and regulation; chemicalsimulation of the structure and function of nitrogenase and bringing forward the model of nitrogenase active center for the first time in inter{2. and synthesis of modelcompounds which were paid attention by colleagues abroad. Finally, the development of nitrogen fixation research inchina in future has been put forward, suggesting that the nifgene regulation and its role in providing crops with nitrogen element, signal transduction and molecular interactions between Rhizobium and legume, coupling between carbonand nitrogen metabolisms, nitrogen fixation andphotosynthesis, and functional genomics of nitrogen-fixing nodule symbiosis, etc., would be actively worked on.

关键词：现状发展生物固氮技术中国固氮酶基因表达微生物植物相互作用化学模型

Spectral Analysis of the Flare of 1998 November 11 based on the Multi-cloud Model

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chinese Journal of Astronomy and Astrophysics 2002年第1期2卷 92-102页

作者： Xiao－MaGu Ming－DeDing YunnanObservatory NationalAstronomicalObservatoriesCASKunming650011 DepartmentofAstronomy NanjingUniversityNanjing210093

We have obtained 2. spectra of Ha and CaII λ8542. for the flare of 1998 November 11, and derived its 2. velocity field and integrated intensity field. The velocity distribution shows that the red-shift and blue-shift velocities lie respectively in the northern and southern parts of the flare and that the maximum velocity seems to be located in two footpoints of the flare loop system. The integrated intensity distribution shows that the CaIIλ8542. line is formed at a lower height than the Ha line, we used 'multi-cloud model' (MCM) to obtain four parameters for the two lines (Doppler width, △λD, Doppler shift, △λ0, line source function, S, and optical depth at the line center, TO). We also estimated the column number densities of hydrogen at the second level, N2. and of the ionized calcium at the third level, N3, as well as the kinetic temperature, Tc. The wide Hα profile at the loop top may be explained by an overlapping of two or more elementary profiles. It is shown that the uncertainty in calibration does not affect the derived Doppler shift and line broadening, only the source function and optical depth.

关键词： Sun: activity-Sun: flares-methods: data analysis

Outer membrane proteins induced by iron deficiency in Anabaena *** 712.

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Progress in Natural Science:Materials International 2009年第11期19卷 1477-1483页

作者： Yanling Dong,Xudong Xu State key laboratory of Freshwater Ecology and Biotechnology,Institute of Hydrobiology,{2. academy of sciences,Wuhan 430072.china [a]State key laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China

Iron deficiency can induce cyanobacteria to synthesize siderophore receptor proteins on the outer membrane to enhance the uptake of *** this study,an outer membrane of high purity was prepared from Anabaena *** 712. based on aqueous polymer two-phase partitioning and discontinuous sucrose density ultra-centrifugation,and the induction of outer membrane proteins by iron deficiency was investigated using 2.D gel *** least five outer membrane proteins were newly synthesized or significantly up-regulated in cells transferred to iron-deficient conditions,which were all identified to be siderophore receptor proteins according to MALDI-TOF-MS *** luciferase reporter genes luxAB were employed to monitor the transcription of the encoding *** genes were induced by iron deficiency at the transcriptional level in different responsive *** activity expressed from an iron-regulated promoter may be used as a bioreporter for utilizable iron in natural water samples.

关键词： Anabaena Outer membrane Siderophore receptors Iron deficiency

Characterization of a sodium-regulated glutaminase from cyanobacterium Synechocystis sp. PCC 6803

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Science china(Life sciences) 2008年第12期51卷 1066-1075页

作者： ZHOU Jie1, ZHOU JunXia1,2. YANG HaoMeng1, YAN ChengShi1 & HUANG Fang1 1 key laboratory of Photosynthesis and Environmental Molecular Physiology, Institute of Botany, {2. academy of sciences, Beijing 100093, china 2.Graduate School of {2. academy of sciences, Beijing 100039, china 1. key laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. Graduate School of chinese academy of {2. Beijing 100039 China

Glutaminase is widely distributed among microorganisms and mammals with important functions. Lit-tle is known regarding the biochemical properties and functions of the deamidating enzyme glutami-nase in cyanobacteria. In this study a putative glutaminase encoded by gene slr2.79 in Synechocystis sp. PCC 6803 was investigated. The slr2.79 was expressed as histidine-tagged fusion protein in Es-cherichia coli. The purified protein possessed glutaminase activity, validating the functional assign-ment of the genomic annotation. The apparent Km value of the recombinant protein for glutamine was 2..6 ± 0.9 mmol/L, which was comparable to that for some of other microbial glutaminases. Analysis of the purified protein revealed a two-fold increase in catalytic activity in the presence of 1 mol/L Na+. Moreover, the Km value was decreased to 12.2.± 1.9 mmol/L in the presence of Na+. These data demon-strate that the recombinant protein Slr2.79 is a glutaminase which is regulated by Na+ through in-creasing its affinity for substrate glutamine. The slr2.79 gene was successfully disrupted in Synecho-cystis by targeted mutagenesis and the △slr2.79 mutant strain was analyzed. No differences in cell growth and oxygen evolution rate were observed between △slr2.79 and the wild type under standard growth conditions, demonstrating slr2.79 is not essential in Synechocystis. Under high salt stress condition, however, △slr2.79 cells grew 1.2.-fold faster than wild-type cells. Moreover, the photosyn-thetic oxygen evolution rate of △slr2.79 cells was higher than that of the wild-type. To further charac-terize this phenotype, a number of salt stress-related genes were analyzed by semi-quantitative RT-PCR. Expression of gdhB and prc was enhanced and expression of desD and guaA was repressed in △slr2.79 compared to the wild type. In addition, expression of two {2. enzymes of ammonium assimi-lation in cyanobacteria, glutamine synthetase (GS) and glutamate synthase (GOGAT) was examined by semi-quant

关键词： cyanobacteria Synechocystis putative glutaminase enzyme activity mutagenesis salt tolerance

A seed-specific AP2.domain transcription factor from soybean plays a certain role in regulation of seed ger-mination

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Science china(Life sciences) 2008年第4期51卷 336-345页

作者： WANG ChunMei, WANG HuiWen, ZHANG JinSong & CHEN ShouYi national key {2. of Plant Genomics, Institute of Genetics and Developmental Biology, chinese academy of sciences, Bei-jing 100101, china national key {2. of Plant Genomics Institute of Genetics Developmental Biology Chinese Academy of Sciences Beijing 100101 China

Plant seed development and germination are under strict temporal and spatial regulation, and tran-scription factors play important roles in this regulation. In the present study we identified an EST ex-pressed specifically in the developing soybean seeds. The full length of the gene was obtained through further RACE analysis and the gene was named GmSGR. Sequence analysis revealed that this gene belonged to the AP2.ERF transcription factor family. Its AP2.domain had the highest similarity with that of the A-3 member AtABI4 of DREB subgroup in the AP2.ERF family in Arabidopsis. GmSGR did not exhibit transcriptional activation activity in the yeast assay system. GmSGR was overexpressed in Arabidopsis and the germination rates of the transgenic seeds were significantly higher than that of the wild type seeds under higher concentrations of ABA and glucose respectively. However, the germina-tion rates of the transgenic seeds were lower than that of control under salt stress. The expression of AtEm6 and AtRD2.B was higher in the seedlings of the transgenic plants than that in the wild-type seedlings. These results suggest that GmSGR may confer reduced ABA sensitivity and enhanced salt sensitivity to the transgenic seeds through regulating the expression of AtEm6 and AtRD2.B genes.

关键词： ABA AP2.ERF transcription factor salt stress seed germination soybean