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Effect of upward ion on field-aligned currents in the near-earth magnetotail

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Science China(Physics,Mechanics & Astronomy) 2007年第5期50卷 673-680页

作者： ZHANG LingQian1, LIU ZhenXing1, MA ZhiWei2, SHEN Chao1, ZHOU XuZhi3.& ZHANG XianGuo3.1 Center for Space and Applied Research, chinese academy of sciences, Beijing 100080, China 2 institute of Plasma Physics, chinese academy of sciences, Hefei 23.03., China 3.School of Earth and Space Science, Peking University, Beijing 100871, China 1. Center for Space and Applied Research Chinese Academy of Sciences Beijing 100080 China 2. institute of Plasma Physics Chinese Academy of Sciences Hefei 230031 China 3. School of Earth and Space Science Peking University Beijing 100871 China

A 3.dimensional resistive MHD simulation was carried out to study the effect of the upward ions on the field-aligned currents (FACs) in the near-earth magnetotail. The simulation results show that the up-flow ions originating from the nightside auroral oval would drift into the center plasma sheet along the magnetic field lines in the plasma sheet boundary, and have an important effect on the field-aligned currents. The main conclusions include that: 1) the upward-ions mainly affect the field- aligned currents in the near-earth magnetotail (inside 15.Re); 2) the generated FACs in the near-earth region have two types, i.e., Region 1 FAC in the high-latitude and Region 2 FAC in the low-latitude; 3. FACs increase with the enhancement of the upward ion flux; 4) with the same flux of the upward ions, FACs enhance with the increase of the velocity of the up-flow ions; 5. the intensification of FACs is also closely related with the latitude of the upward ions, and the ions from the closed field line region generate larger FACs; 6) the generation of FACs is closely related with By created by the upward ions.

关键词： up-flow ions, near-earth magnetotail, field-aligned current

Soil Microbial Population Dynamics along a Chronosequence of Moist Evergreen Broad-leaved Forest Succession in Southwestern China

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Journal of Mountain Science 2010年第4期7卷 327-338页

作者： ZHU Wanze CAI Xiaohu LIU Xingliang WANG Jinxi CHENG Song ZHANG Xiuyan LI Dengyu LI Maihe institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Sichuan academy of Forestry Chengdu 610081 China Siehuan Agricultural University Yaan 625014 China Swiss Federal Research institute WSL Zuereherstrasse 111 CH-8903 Birrnensdorf Switzerland

Little is known about whether soil microbial population dynamics are correlated with forest *** test the hypotheses that(1) soil microbial composition changes over successional stages,and(2) soil microbial diversity is positively correlated with plant species diversity,we determined the soil microbial populations,community composition,and microflora diversity in evergreen broad-leaved forests along a chronosequence of vegetation succession from 5.to 3.0 years in southwestern *** soil microbial community was mainly composed of bacteria(87.1-98.7% of the total microorganisms and 10 genera identified),fungi(0.3.4.0%,7 genera),and actinomycetes(2.1-9.1%,8 species and 1 genus).There were significant differences in soil microbial populations among different successional stages and within the four *** seasonal variations of the soil microbial community may be associated with the seasonal changes in environmental *** changes in soil microbial diversity(Shannon-Wiener index) with successional time followed one-humped,convex curves peaked at-100 years since restoration,which is identical with the trends of the aboveground plant *** plant diversity resulting in enhanced nutrient flow and root exudation may contribute to positive relationships between the soil microbial diversity and plant ***,decreases in soil microbial diversity in the late-successional stages appear to be related to the net loss in species richness that occurs after 100 years since *** findings confirm the intermediate disturbance hypothesis that suggests diversity peaks at midsuccessional stages.

关键词： Actinomycetes Bacteria Fungi Microbial diversity Moist evergreen broad-leavedforest Seasonal dynamics

SiC FIBRE-REINFORCED Ti-BASED COMPOSITE

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中国有色金属学会会刊：英文版 1996年第4期6卷 72-75页

作者： Lu Yuxiong Li Douxing Shi Nanlin Ma Zhongyi Bi Jing(institute of Metal Research,chinese academy of{3.,Shenyang 110015. ACAD SINICA INST MET RESSHENYANG 110015PEOPLES R CHINA

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关键词： CVD SiC fibre β-Ti alloy vacuum hot press diffusion bonding technique SiC_f/Ti composite

The reconstruction and interpretations of lake status at 6 ka and 18 ka *** inland mainland Asia

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chinese Science Bulletin 1998年第14期43卷 1145-1157页

作者： QIN Boqiang 1, SHI Yafeng 1 and YU Ge 2, 3.1. Nanjing institute of Geography & Limnology, chinese academy of sciences, Nanjing 210008, China 2. Dynamic Palaeoclimatology, Lund University, PO Box 117, S 221 00, Lund, Sweden 3. Department of Nanjing institute of Geography & Limnolagy Chinese Academy of Sciences Nanjing China Dynamic Palaeoclimatology Lund University Lund Sweden Department of Geology and Ocean sciences Nanjing University Nanjing China

By means of survey of literature through compilations of sedimentological, biogeological and geomorphologic data, the inland lake level changes in arid or semi arid mainland Asia at 6 and 18 ka B.P. have been reconstructed. The results showed that the lakes from western and northwestern Asia were characterized by very high water levels at 18 ka B.P., but low or intermediate water stands at 6 ka B.P. The high lake level in this region was associated with the southward displacement of westerlies, therefore, the extent of the high lake stand indicated the southern flank of westerlies during the glaciation. Conversely, the lakes from the eastern and southern Asia registered comparative low levels at 18 ka B.P. and significantly high one at 6 ka B.P. The lowering of lake level at 18 ka B.P. was caused by the weakened summer monsoon and the high lake level at 6 ka B.P. by the enhanced summer monsoon induced by the enlarged thermal contrast between land and ocean. The extent of high lake levels indicated the northern boundary of monsoon expansion. Between the above two regions, there is a climatic transitional zone in the Central Asia where the lake behavior was close to that in southeastern Asia at 6 ka B.P. but became similar to that in northwestern Asia at 18 ka B.P. Thus this zone became a transitional sector from the monsoon to the westerlies.

关键词： lake status inland mainland Asia westerlies monsoon.

Nitrogen isotopic geochemical characteristics of crude oils in several basins of China

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Science China Earth sciences 2005年第8期48卷 1211-1219页

作者： CHEN Chuanping1,2, MEI Bowen1 & CAO Yacheng3.1. Jianghan Petroleum University, Jingzhou 43.100, China 2. Huazhong University of Science and Technology, Wuhan 43.047, China 3. Nanjing institute of Soil Science, chinese academy of sciences, Nanjing 210008, China 1. Jianghan Petroleum University 434100 Jingzhou China 2. Huazhong University of Science and Technology 430047 Wuhan China 3. Nanjing institute of Soil Science Chinese Academy of Sciences 210008 Nanjing China

Nitrogen isotopic ratios of crude oils with different physical and chemical properties in several basins of China have been measured and their geochemistry has been studied ele-mentally combined with molecular organic geochemistry methods. The data indicate that δ 15. is in the range of ?6‰-20‰. They vary with the oils in different sedimentary types of basins. The oils forming in the limnic environment have lower δ 15. with the value of about 1‰-5. whereas the oils in saline or semi-saline environment have higher δ 15., with most samples being above 10‰ and some exceeding 17‰. The average nitrogen isotopic ratio of oils from the Ordovician formation in the Tarim Basin is the lowest, with most samples having δ 15. below zero, which reflects possibly the characteristic of the oils originating mainly from the organic matter formed in marine carbonate sedimentary environment. The δ 15. distribution can be altered by fractionation. It increases obviously because of biodegradation and decreases during hydrocarbon migration. However, the effect of nitrogen isotopic fractionation in the short distance migration is uncon-spicuous.

关键词： nitrogen isotope, crude oil, sedimentary environment, isotopic fractionation, China.

Uncertainties in assessing the effect of climate change on agriculture using model simulation and uncertainty processing methods

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chinese Science Bulletin 2011年第8期56卷 729-737页

作者： YAO FengMei QIN PengCheng ZHANG JiaHua LIN ErDa BOKEN Vijendra College of Earth Science Graduate University of Chinese Academy of Sciences Beijing 100049 China Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100094 China chinese academy of Meteorological sciences Beijing 100081 China School of Geoscience Yangtze University Jingzhou 434025 China institute of Environment and Sustainable Development in Agriculture Chinese Academy of Agricultural Sciences Beijing 100081 China Department of Geography and Earth Science University of Nebraska at Kearney Kearney NE 68849 USA

Model simulation is an important way to study the effects of climate change on *** assessment is subject to a range of uncertainties because of either incomplete knowledge or model technical uncertainties,impeding effective decision-making to climate *** the basis of uncertainties in the impact assessment at different levels,this article systematically summarizes the sources and propagation of uncertainty in the assessment of the effect of climate change on agriculture in terms of the climate projection,the assessment process,and the crop models linking to climate ***,techniques and methods focusing on different levels and sources of uncertainty and uncertainty propagation are introduced,and shortcomings and insufficiencies in uncertainty processing are pointed ***,in terms of how to accurately assess the effect of climate change on agriculture,improvements to further decrease potential uncertainty are suggested.

关键词：不确定性模型影响评估气候变化农业影响模型模拟不确定性传播气候预测气候模型

Genetic variations of glycinin subunit genes among cultivated and wild type soybean species

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Progress in Natural Science:Materials International 2008年第1期18卷 33-41页

作者： Chunmei Wang, Xiaolei Wu, Faxing Jia, Jinsong Zhang *, Shouyi Chen * National Key Laboratory of Plant Genomics, institute of Genetics and Developmental biology, chinese academy of sciences, Beijing 100101, China National Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China

Glycinin is a predominant storage protein in most soybean accessions. It is a hexamer constituted by five major subunits, which can be classified into two groups. Group I contains G1, G2 and G3. and Group II contains G4 and G5. The genes encoding these subunits have been designated from Gy1 to Gy5. respectively. In the present study, Gy1 genomic fragments were cloned from wild accessions of sub- genera Glycine glycine, Glycine soja and a cultivar of Glycine max. Their sequences and the deduced amino acid sequences were com- pared. The residues critical for assembling of G1 subunits from the wild perennial accession were conservative. The Gy4 fragments were cloned from two wild perennial accessions and compared with that from subgenus Soja. The intron 3.of Gy4 had abundant vari- ations between the subgenera G. soja and G. glycine as well as within the subgenus G. glycine. Abundant variations existed in the dis- ordered regions 3.and 4 of G4 subunits from two wild perennial accessions. The genomic organization of glycinin genes was analyzed in 19 accessions from subgenera Soja and Glycine. The hybridization patterns were identical among the accessions of subgenus Soja. On the contrary, abundant polymorphisms existed between the accessions from subgenus Glycine. These results indicated that gly- cinin genes have high degree of conservation within subgenus Soja but more variations within subgenus Glycine.

关键词： Genetic variation Glycinin subunit genes Soybean

Association of DRD2 polymorphisms and chlorpromazine-induced extrapyramidal syndrome in chinese schizophrenic patients

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Acta Pharmacologica Sinica 2006年第8期27卷 966-970页

作者： Sheng-nan WU~(2,3.5.6) Rui GAO~(2,3.6) Qing-he XING~(2,3.6) Hua-fang LI~4 Yi-feng SHEN~4 Niu-fan GU~4 Guo-yin FENG~4 Lin HE~(2,3.7)2 Bio-X Life Science Research Center,Shanghai Jiaotong University,Shanghai 20003.,China 3.institute of Nutritional sciences,SIBS,{3. {3. of sciences,Shanghai 20003.,China 4 Shanghai institute of Mental Health,Shanghai 20003.,China 5.Shanghai institute of Hypertension,Ruijin Hospital,Medical School of Shanghai Jiaotong University,Shanghai 200025.China Bio-X Life Science Research Center Shanghai Jiaotong University Shanghai 200030 China

Aim:Extrapyramidal syndrome (EPS) is most commonly affected by typical antip-sychotic drugs that have a high affinity with the D2 ***,manyresearch groups have reported on the positive relationship between the geneticvariations in the DRD2 gene and the therapeutic response in schizophrenia pa-tients as a result of the role of variations in the receptor in modulating *** this study,we evaluate the role DRD2 plays in chlorpromazine-induced EPS in schizophrenic ***:We identified seven SNP(singlenucleotide polymorphism) (-141Cins>del,TaqIB,TaqID,Ser3.1Cys,rs6275.rs6277and TaqIA) in the DRD2 gene in 146 schizophrenic inpatients (5. with EPS and 87without EPS according to the Simpson-Angus Scale) treated with chlorpromazineafter 8 *** alleles of all loci were determined by PCR (polymerase chainreaction).Results:Polymorphisms TaqlD,Ser3.1Cys and rs6277 were not poly-morphic in the population recruited in the present *** statistical signifi-cance was found in the allele distribution of-141Cins>del,TaqIB,rs6275.andTaqIA or in the estimated haplotypes (constituted by TaqIB,rs6275.and TaqIA) inlinkage disequilibrium between the two ***:Our results did notlend strong support to the view that the genetic variation of the DRD2 gene playsa major role in the individually variable adverse effect induced by chlorpromazine,at least in chinese patients with *** results confirmed a previousstudy on the relationship between DRD2 and EPS in Caucasians.

关键词： dopamine receptors basal ganglia disease polymorphism chlorpromazine schizophrenia

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魔芋低聚糖硫酸酯的制备及抗病毒活性研究

天然产物研究与开发 2002年第1期14卷 17-20页

作者：杨敏蒙义文中国科学院成都生物研究所成都610041

从酶解魔芋干粉中提取分子量在 15.0 0左右的葡甘露低聚糖Apkos ,采用吡啶氯磺酸法制备了它的硫酸酯衍生物S Apkos,其硫含量为 8 2 8% ,取代度 (Ds)为 0 .5.7。用Vero细胞和单纯疱疹病毒 2型 (HSV 2 )考察硫酸酯化前后低聚糖的抗病毒... 详细信息

从酶解魔芋干粉中提取分子量在 15.0 0左右的葡甘露低聚糖Apkos ,采用吡啶氯磺酸法制备了它的硫酸酯衍生物S Apkos,其硫含量为 8 2 8% ,取代度 (Ds)为 0 .5.7。用Vero细胞和单纯疱疹病毒 2型 (HSV 2 )考察硫酸酯化前后低聚糖的抗病毒活性。结果表明 ,本身无抗HSV 2活性的Apkos硫酸酯化后产生了抗病毒活性 ,5.0 0～ 40 0 0 μg/ml的S Apkos能很好地抑制HSV 2引起的Vero细胞病变 ,而在5.0 0 μg/ml及以上浓度条件下能完全抑制HSV

关键词：魔芋低聚糖硫酸酯单纯疱疹病毒