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Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2.and Li Jianping2.1. College of Atmospheric sciences, Lanzhou University, Lanzhou 73.000, {3. 2. LASG, {2. of Atmospheric Physics, chinese Academy of sciences, Beijing 10002., {3.) College of Atmospheric sciences Lanzhou University Lanzhou 730000 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1948—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

Sequence analysis of mRNA polyadenylation signals of rice genes

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chinese Science Bulletin 2006年第9期51卷 1069-1077页

作者： LU Ying1, 2. GAO Chenxi1,2.3.& HAN Bin1,3.41. National Center for Gene Research, Shanghai institutes for Biological {3., {2. Academy of {3., Shanghai 2.02.3. china 2. Graduate School of the {2. Academy of {3., Beijing 10003., china 3. institute of Plant Physiology and Ecology, Shanghai institutes for Biological {3., {2. Academy of {3., Shanghai 2.003.0} china National Center for Gene Research Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200233 China Graduate School of the chinese Academy of sciences Beijing 100039 China institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 200032 China

The formation of eukaryotic mRNAs involves the cleavage and polyadenylation of pre- mRNAs. To investigate the sequence requirement of putative polyadenylation signals (PASs), poly(A) sites and downstream elements (DUEs) in 3.-end-pro- cessing in rice, we compared expressed sequences tags (ESTs) with poly(A) extremity to full-length cDNA sequences and constructed a database of 12.69 pre- mRNA sequences in ?40―+40 nt surrounding the poly(A) sites, which were from 9953.genes. The al- ternative poly(A) sites were revealed in approxi- mately 2.% of mRNAs. Nearly 80% of pre-mRNAs showed stringent requirement of the YA (CA or UA) at poly (A) sites for polyadenylation. About 7.9% had the AAUAAA signals on ?40―?1 nt upstream of the poly(A) sites. Over 60% of mRNAs probably used the one- or two-base variants of AAUAAA hexamers as their PASs in 3. fragments. The single-base variants of AAUGAA revealed the high frequency in 11.5% of 3. fragments. The DUEs were detected in 90% of pre- mRNAs, especially more than half of the pre-mRNAs with multi-base variants of AAUAAA had the DUEs surrounding the poly(A) site. The location of DUE is also important for defining the cleavage site. Al- though most of the rice pre-mRNAs did not contain AAUAAA signal, the existence of downstream ele- ments ensured the efficiency of cleavage-polyade-

关键词：多聚腺苷酸序列分析 mRNA 水稻基因工程

Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin

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Science china Earth sciences 2006年第7期49卷 731-738页

作者： QIAO Yansong1,3. GUO Zhengtang2.1, HAO Qingzhen1, YIN Qiuzhen1, YUAN Baoyin1 & LIU Tungsheng1 1. institute of Geology and Geophysics, chinese Academy of {2., Beijing 10002., china 2. institute of Earth Environment, chinese Academy of {2., Xi’an 710075, china 3. institute of Geomechanics, chinese Academy of Geological {2., Beijing 100081, china institute of Geology and Geophysics Chinese Academy of Sciences Beijing China institute of Geomechanics Chinese Academy of Geological Sciences Beijing China institute of Earth Environment Chinese Academy of Sciences Xi’an China

In this study, grain-size of 507 bulk samples from the QA-I Mioceneloess-soil sequence at Qinan were analyzed, and the grain-size features are compared with those oftypical Quaternary loess and soil samples, representative lacustrine and fluvial samples. Theresults indicate that the grain-size distribution pattern of the Miocene loess is essentiallysimilar to that of Quaternary loess, but greatly differs from the lacustrine and fluvial *** layers are regularly coarser than soil layers, indicating cyclical climate changes. Mediangrain-size along the 2.3.1 m sequence varies from 6 to 13.μm and the > 63.μm fraction representsonly 5.3. in maximum, 0.9% in average. Long-term grain-size variations are consistent with the loessaccumulation rate at Qinan and with the eolian mass accumulation rate in the North Pacific. Thesefeatures firmly indicate an eolian origin of the studied sequence, and also reveal a coeval changesbetween the long-term changes of eolian grain-size and continental aridity in the dust sourceregions.

关键词： Qinan, Miocene loess-soil sequence, grain-size, eolian origin.

Global analysis theory of climate system and its applications

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chinese Science Bulletin 2003年第10期48卷 1034-1039页

作者： LI Jianping1,2.& CHOU Jifan2.3.1. LASG, institute of Atmospheric Physics, {3. Academy of {2., Beijing 10002., china 2. Department of Atmospheric {2., Lanzhou University, Lanzhou 73.000, china 3. Training Center for china Meteorological Administration, Beijing 100081, china Department of Atmospheric sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The idea and main theoretical results of the global analysis theory of climate system are briefly summarized in this paper. A theorem on the global behavior of climate system is given, i.e. there exists a global attractor in the dynamical equations of climate, any state of climate system will be evolved into the global attractor as time increases, indicating the nonlinear adjustment process of climate system to external forcing. The different effects of external forcing, dissipation and nonlinearity on the long-term behavior of solutions are pointed out, and some main applications of the global analysis theory are also introduced. Especially, three applications, the adjustment and evolution processes of climate, the principle of numerical model design and the optimally numerical integration, are discussed.

关键词：整体分析理论气侯体系应用不定性计算法则气侯科学数字模型

Organic geochemical studies of sinking particulate material in china sea area Ⅱ——Geochemical significance of compositional features of ketone, aldehyde and alcohol compounds

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chinese Science Bulletin 1997年第22期42卷 1894-1898页

作者： DUAN Yi,CUl Mingzhong, MA Lanhua, SONG Jinming, ZHOU Shixin and LUO Binjie1. Lanzhou institute of Geology, chinese Academy of {2., Lanzhou 73.000, {3. 2. Earthquake Research institute of Lanzhou, SSB, Lanzhou 73.000, {3. 3. institute of Oceanology, chinese Academy of {2., Qingdao 2.6071, {3. Lanzhou institute of Geology Chinese Academy of Sciences Lanzhou China Earthquake Research institute of Lanzhou SSB Lanzhou China institute of Oceanology Chinese Academy of Sciences Qingdao China

SINKING particulate organic matter of the sea plays an important role in marine environment. Itnot only provides food for marine organisms and takes part in chemical cycling, but also pro-vides sedimentary organic matter for marine sediments. Therefore, researchers always payclose attention to the source and processes of transport and transformation of marine sinkingparticulate organic matter. Its transport process can be understood by measuring the

关键词： marine sinking paniculate material composition of lipid compounds organic matter source and biochemical pro-cesses.

Discovery of low grade metamorphic volcanic rock sheets within UHP in Dabie Mts. and its implications

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chinese Science Bulletin 1997年第14期42卷 1199-1203页

作者： DONG Shuwen, WANG Xiaofeng and HUANG Dezhi1. chinese Academy of Geological sciences (CAGS), Beijing 10003., {2. 2. institute of Geomechanics of CAGS, Beijing 100081 {2. 3. Anhui institute of Geological sciences, Hefei 2.0001 chinese Academy of Geological sciences (CAGS) Beijing 100037 China

THE ultrahigh-pressure metamorphic zone (UHP), outcropping in the central and southernDabie Mts. with an area of about 1000 km^2. may be the largest one in the world. The forma-tion and exhumation mechanism of the UHP rocks become a hot point in the study of continen-tal orogen. The first finding of the Shiqiao structural window, which is composed of low

关键词： ultrahigh-pressure metamorphic zone (UHP) low grade metamorphic rock sheets Dabie Mts.

Characteristics and geological significance of olivine xenocrysts in Cenozoic volcanic rocks from western Qinling

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Progress in Natural Science:Materials International 2006年第12期16卷 1300-1306页

作者： SU Benxun~ 1,2.**, ZHANG Hongfu~1, XIAO Yan~ 1,2.and ZHAO Xinmiao~ 1,2.(1. State Key Laboratory of Lithospheric Evolution, {3. of Geology and Geophysics, chinese Academy of {2., Beijing 10002., china 2. Graduate School of chinese Academy of {2., Beijing 10003., china) State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China. Graduate School of chinese Academy of sciences Beijing 100039 China

Cenozoic volcanic rocks from the Haoti, Dangchang County of the western Qinling Mountains, contain a few clearly-zoned olivines. These olivines are relatively big in grain sizes and usually have cracks or broken features. Their cores have similar compositions （Mg#=90.4-91.0） to those for the peridotitic xenoliths entrained in host volcanic rocks and their rims are close to the compositions of olivine phenocrysts （Mg#=85.5-81.9）. The CaO contents in these zoned olivines are lower than 0.1%. These features demonstrate that the clearly-zoned olivines are xenocrysts and disaggregated from mantle peridotites. The zoned texture was the result of the interaction between the olivine and host magma. Available data show that the volcanic rocks would have been derived from the mantle source metasomatized by subducted hydrathermally-altered oceanic crust. The formation of these Cenozoic volcanic rocks was perhaps related to the rapid uplift of the Tibetan Plateau.

关键词： Western Qinling Dangchang Haoti Cenozoic volcanic rocks olivine xenocrysts zoned texture.

CO observations of massive star forming regions at different evolutionary phases

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Science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 626-640页

作者： CHEN Xi1,2. XU Ye1,3. SHEN Zhiqiang1,3.& LI Jingjing1,2.1. Shanghai Astronomical Observatory, chinese Academy of {3., Shanghai 2.003., {2. 2. Graduate School of the chinese Academy of {3., Beijing 10003., {2. 3. Joint institute for Galaxy and Cosmology, Shanghai Astronomical Observatory and the University of Science and Technology of {2., Shanghai 2.003., {2. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China

The 12.O (J=1-0), 13.O (J=1-0) and C18O (J=1-0) emissions in 9 massive star forming regions, which are believed to be at different stages of massive star formation, were mapped with the 13.7 m millimeter wave telescope at Qinghai Station of Purple Mountain Observatory. Of the observed 9 sources, 13.O cores were detected in seven of them, and C18O cores in five of them. And only two sources associated with C18O cores and H2. masers showed the extended structures and strong outflows. This is the first detection of outflow associated with IRAS 2.566+582. in the observing field of S152.S153. The physical parameters of cores and outflows for these sources, derived from Local Thermal Equilibrium (LTE) analysis, are presented. These observing results suggest that the C18O cores will only appear when the gas density is high enough and the probability to have an outflow is very high when the clumps show the C18O and H2. maser simulta- neously.

关键词： star formation cloud core outflow H2. maser

Parentage determination of an isolated Yangtze finless porpoise population Neophocaena phocaenoides asiaeorientalis in the Yangtze Tian-e-Zhou Baiji National Natural Reserve based on molecular data

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Progress in Natural Science:Materials International 2005年第2期15卷 54-61页

作者： XIA Junhong 1,2. ZHENG Jinsong 1,2. XU Limei 1,2.and WANG Ding1*(1. {3. of Hydrobiology, chinese Academy of {2., Wuhan 43.072. china 2. Graduate School of the chinese Academy of {2., Beijing 10003., china) institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China. Graduate School of the chinese Academy of sciences Beijing 100039 China

Reproductive behaviors are poorly known for the Yangtze finless porpoise Neophocaena phocaenoides asiaeorientalis. In this study, the parentage of an isolated Yangtze finless porpoise population inhabiting the Yangtze Tian-e-Zhou Baiji National Natural Reserve is determined by analysis of microsatellite loci and mitochondrial DNA (mtDNA) control region sequences, and the porpoise's reproductive behaviors are studied. Overall 4 full parentage assignments and additional 3.single parentage assignments were determined for the population of 2. individuals. The analysis shows that their estimated reproductive cycle is shorter than that reported previously and there probably exists an overlapping between gestation and lactation period. The study also shows that the female does not show fidelity to a particular male for breeding and vice versa, the oldest males did not monopolize mating and the dominance rank could not be so strict for the porpoise society. Moreover, the porpoise's mating pattern and relatedness among candidate parents are discussed here. These results provide important information for making guidelines of management and conservation for this protected population.

关键词： Yangtze finless porpoise isolated population reproductive behavior parentage