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Science china Earth sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2,3 & WANG Huijun2 1. Nansen-Zhu International Research Center, Institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, china 3. Graduate University of the chinese academy of sciences, beijing 100049, china 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of Atmospheric Science Yunnan University Kunming 650091 China 3. Graduate University of the chinese academy of sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

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, chinese academy of sciences, beijing 100093, china 2 Graduate School of chinese 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 sciences 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 slr2079 in Synechocystis sp. PCC 6803 was investigated. The slr2079 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 26.6 ± 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 Slr2079 is a glutaminase which is regulated by Na+ through in-creasing its affinity for substrate glutamine. The slr2079 gene was successfully disrupted in Synecho-cystis by targeted mutagenesis and the △slr2079 mutant strain was analyzed. No differences in cell growth and oxygen evolution rate were observed between △slr2079 and the wild type under standard growth conditions, demonstrating slr2079 is not essential in Synechocystis. Under high salt stress condition, however, △slr2079 cells grew 1.25-fold faster than wild-type cells. Moreover, the photosyn-thetic oxygen evolution rate of △slr2079 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 △slr2079 compared to the wild type. In addition, expression of two key 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

solar Flare activity and Variability of Electric Current Helicity

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chinese Journal of Astronomy and Astrophysics 2002年第1期2卷 81-91页

作者： KimJikSu Hong－QiZhang 等 PyongyangastronomicalObservatory AcademyofSciencesDPRofKorea nationalastronomicalobservatories ChineseAcademyofSciencesBeijing100012

Recent study using Huairou vector magnetograph data shows that durlug flare activity, the current helicity exhibits rapid and substantial variations and, in some cases, a recovering phase. We considered various representative the magnetic configurations. First, interacting twisted magnetic flux tubes are analyzed separately for positive, negative and mixed-sign helicity regions. The results show that the helicity during flares decreases in positive-sign, and increases in negative-sign regions. Then, flaring arcade also shows that the magnitude of the helicity decreases after flares. We also investigated current sheets formed by sheared magnetic field and showed that the current helicity (with either positive and negative signs) vanishes after reconnection. The emergence of twisted flux tubes which can trigger flares may be another source of flare-associated variability of current helicity. We demonstrate the relevance of current helicity to the description of flare activity by comparing its variation with that of shear angle in the active region AR 6891.

关键词： Sun: flare -Sun: current helicity - Sun: magnetic shear

Transition metal complexes bearing 2,6-bis(imino)pyridyl:Synthesis, structure, ethylene polymerization/oligomerization studies

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Science china Chemistry 2005年第z1期48卷 45-49页

作者： SU Biyun,ZHAO Jianshe & SUN Wenhua Department of Chemistry,Northwest University,Xi’an 710069,china State key laboratory of Engineering Plastics and Center for Molecular Science,Institute of Chemistry,chinese academy of sciences,beijing 100080,china NW Univ Xian Dept Chem Xian 710069 Peoples R China chinese Acad Sci State Key Lab Engn Plast Beijing 100080 Peoples R China chinese Acad Sci Inst Chem Ctr Mol Sci Beijing 100080 Peoples R China

A series of new complexes {2,6-bis[1-((2-methyl-4-methoxyphenyl)imino)ethyl]pyri-dine}MCI2 [M=Fe(Ⅱ) (2), Co(Ⅱ) (3), Ni(Ⅱ) (4), Cu(Ⅱ) (5), Zn(Ⅱ) (6)] have been synthesized. At 25℃, using 500 equiv of methylaluminoxane (MAO), the activities of Fe(Ⅱ), Co(Ⅱ) catalysts can reach 4.02×106 g/mol-Fehatm for ethylene polymerization and 3.98×105 g/mol-Cohatm for ethylene oligomerization. The effects of polymerization conditions such as reaction temperature, Al/M molar ratio and time on the activity of catalyst have been explored.

关键词： Bis(imino)pyridine transition metal complex, ethylene polymerization/oligomerization, catalytic activity.

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 laboratory of Plant Genomics, Institute of Genetics and Developmental Biology, chinese academy of sciences, Bei-jing 100101, china national key laboratory 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 AtRD29B 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 AtRD29B genes.

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

Environmental archaeology of the Dachang region in the Daning Valley,the Three Gorges reservoir region of the Yangtze River,china

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chinese Science Bulletin 2008年第S1期53卷 140-152页

作者： ZHANG Yun 1 &ZHU Cheng 2 1 State key laboratory of Vegetation and Environmental Change,Institute of Botany,chinese academy of sciences,beijing 100093, china 2 School of Geographic and Oceanographic sciences,Nanjing University,Nanjing 210093,china 1. State key laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China 2. School of Geographic and Oceanographic sciences Nanjing University Nanjing 210093 China

Environmental archaeology of archaeological sites on both sides of the Dachang section in the Daning River,the Three Gorges of the Yangtze River,shows that riverbed evolution has a great influence on the distribution of archaeological sites during the prehistorical and historical period,and it restricts human activity and the development of ancient *** investigation,dating data,paleocurrent analysis of 100 gravels on the riverbed and archaeological excavation reveal that the riverbed of the Dachang section developed in the Shuangyantang region during the early stage,after about 30 kaBP it shifted westward gradually and reached the present *** with the westward shift,the focus of ancient culture changed for several *** the Western Zhou Dynasty's period,the east riverbank of the Daning River was the main residential *** the Han Dynasty,along with the westward shift,the living space of ancient people was no longer confined to the east riverbank and the focus of culture moved *** the Zhangjiawan site became the main dwelling *** the late Han Dynasty, the villages were flooded and the ancients had to immigrate to a high *** of the Han and the Jin Dynasties outcropped on the flood plain of the east bank because their surface sediments were eroded by several flood events and the westward shift of the riverbed.

关键词： the Daning River environmental archaeology the Shuangyantang site the Zhangjiawan site tombs of the Han and the Jin Dynasties

Induction of nicotine in tobacco by herbivory and its relation to glucose oxidase activity in the labial gland of three noctuid caterpillars

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chinese Science Bulletin 2004年第15期49卷 1596-1601页

作者： ZONG Na1,2 & WANG Chenzhu1 1.State key laboratory of Integrated Management of Insects & Rodents,Institute of Zoology,chinese academy of sciences,beijing 100080,china 2.Graduate School of chinese academy of sciences,beijing 100080,china Correspondence should be addressed to Wang Chenzhu(e-mail: czwang@***) State key laboratory of Integrated Management of Insects & Rodents Institute of Zoology Chinese Academy of Sciences Beijing 100080 China Graduate School of chinese academy of sciences Beijing 100080 China

Tobacco Nicotiana tabacum L. is a host plant of Helicoverpa armigera (Hübner), Helicoverpa assulta Guenée and Spodoptera litura (Fabricius) (Lepidoptera, Noctuidae). The difference in leaf nicotine response to the feeding by these three larvae and the mechanical simulation of their feeding was examined by HPLC. Results indicated that nico- tine induction was suppressed by H. armigera and H. assulta larvae feeding or by simulated damage treated with their labial glands extracts. The production of nicotine was also suppressed by the glucose oxidase from Aspergillus niger when it was treated on mechanically wounded leaf area. On the contrary, the nicotine production was stimulated by S. litura larva feeding or by simulated damage treated with its labial gland extract. Heat denature can not counteract the stimulation effect of the S. litura labial gland extracts to to- bacco nicotine production. The glucose oxidase activity was detected in labial gland extracts of both H. armigera and H. assulta, but the activity in H. armigera was significantly higher than that in H. assulta. No glucose oxidase activity was detected in labial gland extracts of S. litura. It is shown that the glucose oxidase activity in labial glands of caterpil- lars plays an important role in the nicotine response to her- bivory. The glucose oxidase was mainly contained in the la- bial gland of H. armigera larva, and had the highest activity at pH 7.0. D-Glucose was the optimal substrate of the glucose oxidase. Labial gland glucose oxidase activities varied daily during larval development with high activities found when larvae were actively feeding.

关键词：烟碱烟草葡萄糖氧化酶三夜蛾毛虫棉铃虫烟毒虫斜纹夜蛾

Polar Coronal Holes During solar Cycles 22 and 23

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chinese Journal of Astronomy and Astrophysics 2005年第5期5卷 531-538页

作者： Jun Zhang J. Woch S. Solanki national astronomical observatories Chinese Academy of Sciences Beijing 100012 Max-Planck-Institut fiir Sonnensystemforschung Katlenburg-Lindau D-37191 Germany

Data from the solar Wind Ion Composition Spectrometer （SWICS） on Ulysses and synoptic maps from Kitt Peak are used to analyze the polar coronal holes of solar activity cycles 22 and 23 （from 1990 to end of 2003）. In the beginning of the declining phase of solar cycles 22 and 23, the north polar coronal holes （PCHs） appear about one year earlier than the ones in the south polar region. The solar wind velocity and the solar wind ionic charge composition exhibit a characteristic dependence on the solar wind source position within a PCH. From the center toward the boundary of a young PCH, the solar wind velocity decreases, coinciding with a shift of the ionic charge composition toward higher charge states. However, for an old PCH, the ionic charge composition does not show any obvious change, although the latitude evolution of the velocity is similar to that of a young PCH.

关键词： Sun: coronal - Sun: particle emission - Sun: solar wind

Highly stereospecific polymerization of isoprene with homogeneous binary Ziegler-Natta catalysts based on NCN-pincer neodymium precursor

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Science china Chemistry 2010年第8期53卷 1641-1645页

作者： LIU DongTao1,2,CUI DongMei1 & GAO Wei3 1State key laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry,chinese academy of sciences,Changchun 130022,china 2Graduate University of chinese academy of sciences,beijing 100039,china 3School of Chemistry,Jilin University,Changchun 130012,china 1. State key laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China2. Graduate University of Chinese Academy of Sciences Beijing 100039 China3. School of Chemistry Jilin University Changchun 130012 China

The aryldiimine NCN-pincer stabilized neodymium dichloride combined with aluminum alkyls established a new type of homogeneous binary neutral Ziegler-Natta catalyst *** system exhibited high activity and high cis-1,4 selectivity for the polymerization of isoprene (Tp=20 °C,98.2%;Tp=-20 °C,> 99%).Such catalytic performances remained under a broad range of polymerization temperatures and monomer-to-neodymium ratios (from 500 to 8000),reaching high number-average molecular weight (Mn=1582 kg/mol) and relatively narrow molecular weight distribution (PDI=1.68),which was,however,influenced by the amount and bulkiness of aluminum *** investigation of the polymerization was performed,which showed the number-average molecular weight of the resultant polyisoprene had an almost linear correlation with the conversion,suggesting,in some degree,the polymerization with this catalytic system was controllable.

关键词： neodymium cis-1 4 selectivity NCN-pincer complex polyisoprene

An experimental indoor phasing system based on active optics using dispersed Hartmann sensing technology in the visible waveband

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Research in Astronomy and Astrophysics 2011年第9期11卷 1111-1122页

作者： Yong Zhang Gen-Rong Liu Yue-Fei Wang Ye-Ping Li Ya-Jun Zhang Liang Zhang Yi-Zhong Zeng Jie Zhang national astronomical observatories / Nanjing Institute of astronomical Optics ＆ Technology Chinese Academy of Sciences Nanjing 210042 China key laboratory of astronomical Optics ＆ Technology Nanjing Institute of Astronomical Optics ＆ Technology Chinese Academy of Sciences Nanjing 210042 China Graduate University of chinese academy of sciences Beijing 100049 China

A telescope with a larger primary mirror can collect much more light and resolve objects much better than one with a smaller mirror, and so the larger version is always pursued by astronomers and astronomical technicians. Instead of using a monolithic primary mirror, more and more large telescopes, which are currently being planned or in construction, have adopted a segmented primary mirror design. Therefore, how to sense and phase such a primary mirror is a key issue for the future of extremely large optical/infrared telescopes. The Dispersed Fringe Sensor （DFS）, or Dispersed Hartmann Sensor （DHS）, is a non-contact method using broadband point light sources and it can estimate the piston by the two-directional spectrum formed by the transmissive grating＇s dispersion and lenslet array. Thus it can implement the combination of co-focusing by Shack-Hartmann technology and phasing by dispersed fringe sensing technologies such as the template-mapping method and the Hartmann method. We introduce the successful design, construction and alignment of our dis- persed Hartmann sensor together with its design principles and simulations. We also conduct many successful real phasing tests and phasing corrections in the visible waveband using our existing indoor segmented mirror optics platform. Finally, some conclusions are reached based on the test and correction of experimental results.

关键词： astronomical instrumentation -- methods and techniques -- instrumen- tation: active optics -- adaptive optics