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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., {12. 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.

Identification of human dopamine receptors agonists from chinese herbs

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Acta Pharmacologica Sinica 2007年第1期28卷 132-139页

作者： Yi-lin ZHANG~(1,2.3.4. Hai-qing ZHANG~(1,2.3.4. Xiao-yu LIU~3.Shi-neng HUA~3.Lu-bing ZHOU~3.Jun YU~2.Xue-hai TAN~(3.5)1 Graduate School of the {3. academy of {2.,beijing 10003.,{14. 2.beijing Genomics Institute,{3. academy of {2. beijing 1013.0,{14. 3.HD Bio{2. Co Ltd,Shanghai 2.12.3.{14. Graduate School of the chinese academy of {2. Beijing China beijing Genomics Institute Chinese Academy of Sciences Beijing China HD Biosciences Co Ltd Shanghai China

Aim:To find human dopamine receptors,especially Dl-like receptor specific ago-nists from chinese herbs as potential antihypertension drug ***:TwoD l-like receptor cell lines carrying a μ-lactamase reporter gene,and a D2.receptorcell line coexpressing a promiscuous G protein G15 were constructed using HEK2.3.ells.A natural compound library made from fractionated samples of herbal ex-tracts was used for high-throughput screening（HTS）against one of the cell lines,HEK/D5R/*** interested hits were evaluated for their activities againstvarious dopamine ***:Fourteen hits were identified from primaryscreening,of which 2.of the better hit samples,HD052. and HD0059,were selectedfor further material and activity analysis,and to obtain 2.compounds that ap-peared as 2.single peaks in HPLC,HD052.H01 and ***0059H01could activate D 1,D2.and D5 receptors,with EC50values of 2.2. μg/mL,0.85 μg/mL,and 1.4. μg/mL,***052.H01 could only activate DlR and D5Rwith EC50values of 2.95 μg/mL and 8.3. μg/***:We established cell-based assays for 3.different human dopamine receptors and identified specificagonists HD052.H01 and HD0059H01 through *** specific agonist to D1-like receptors,HD052.H01,may become a new natural product-based drug leadfor antihypertension treatment.

关键词： dopamine receptors natural products high throughput screening hypertension

Review on the study of entanglement in quantum computation speedup

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chinese Science Bulletin 2007年第16期52卷 2161-2166页

作者： DING ShengChao1,3.& JIN Zhi1,2.1 Institute of Computing Technology,chinese academy of {2.,beijing 100080,china 2.academy of Mathematics and Systems Science,chinese academy of {2.,beijing 100080,china 3.Graduate University of chinese academy of {2.,beijing 100080,china Institute of Computing Technology Chinese Academy of Sciences Beijing China Graduate University of chinese academy of {2. Beijing China academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China

The role the quantum entanglement plays in quantum computation speedup has been widely disputed. Some believe that quantum computation's speedup over classical computation is impossible if entan-glement is absent,while others claim that the presence of entanglement is not a necessary condition for some quantum algorithms. This paper discusses this problem systematically. Simulating quantum computation with classical resources is analyzed and entanglement in known algorithms is reviewed. It is concluded that the presence of entanglement is a necessary but not sufficient condition in the pure state or pseudo-pure state quantum computation speedup. The case with the mixed state remains open. Further work on quantum computation will benefit from the presented results.

关键词：量子论量子纠缠量子计算加速模拟

Population information extraction in Chaohu watershed based on RS and GIS

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chinese Science Bulletin 2003年第2期48卷 181-183页

作者： LIU Jianjun1,2.& LI Chunlai3.1. Institute of Geochemistry, chinese academy of {2., Guiyang 550002. china 2. Graduate School, chinese academy of {2., beijing 10003., china 3. National Astronomical Observatories, chinese academy of {2., beijing 100012. china Correspondence should be addressed to Liu Jianjun (e-mail: dhsliujj@ ***) Institute of Geochemistry Chinese Academy of Sciences Guiyang China Graduate School Chinese Academy of Sciences Beijing China National Astronomical Observatories Chinese Academy of Sciences Beijing China

It is always difficult to extract population in-formation of small watershed during the region environment assessment. The report adopted compound areal interpola-tion to study the population in Chaohu watershed with the GIS technique and landuse interpretation data from remote sensing. The result indicated that the method is effective to extract population information of small watershed.

关键词：巢湖流域人口分布信息提取 RS GIS 小流域生态环境评价

Control of atmospheric CO_2.concentrations by 2.50: A calculation on the emission rights of different countries

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Science china Earth sciences 2009年第10期52卷 1447-1469页

作者： DING ZhongLi1, DUAN XiaoNan2. GE QuanSheng3.& ZHANG ZhiQiang4.1 Institute of Geology and Geophysics, chinese academy of {2., beijing 10002., china 2.The General Office of chinese academy of {2., beijing 100864. china 3.Institute of Geographic {2. and Natural Resources Research, chinese academy of {2., beijing 100101, china 4.The Lanzhou Branch of the National Science Library, the Scientific Information Center for Resources and Environment, Lanzhou 73.000, china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China The General Office of chinese academy of {2. Beijing China Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China The Lanzhou Branch of the National Science Library the Scientific Information Center for Resources and Environment Lanzhou China

This paper is to provide quantitative data on some critical issues in anticipation of the forthcoming international negotiations in Denmark on the control of atmospheric CO2.concentrations. Instead of letting only a small number of countries dominate a few controversial dialogues about emissions reductions, a comprehensive global system must be established based on emissions allowances for different countries, to realize the long-term goal of controlling global atmospheric CO2.concentrations. That a system rooted in "cumulative emissions per capita," the best conception of the "common but differentiated responsibilities" principle affirmed by the Kyoto Protocol according to fundamental standards of fairness and justice, was demonstrated. Based on calculations of various countries' cumulative emissions per capita, estimates of their cumulative emissions from 1900 to 2.05, and their annual emissions allowances into the future (2.06―2.50), a 4.0 ppmv atmospheric CO2.concentration target was set. According to the following four objective indicators―total emissions allowance from 1900 to 2.50, actual emissions from 1900 to 2.05, emissions levels in 2.05, and the average growth rate of emissions from 1996 to 2.05―all countries and regions whose population was more than 3.0000 in 2.05 were divided into four main groups: countries with emissions deficits, countries and regions needing to reduce their gross emissions, countries and regions needing to reduce their emissions growth rates, and countries that can maintain the current emissions growth rates. Based on this proposal, most G8 countries by 2.05 had already expended their 2.50 emissions allowances. The accu-mulated financial value based on emissions has reached more than 5.5 trillion US dollars (2. dollars per ton of CO2.. Even if these countries could achieve their ambitious emissions reduction targets in the future, their per capita emissions from 2.06 to 2.50 would still be much higher than those of developing coun

关键词： international negotiations on climate change cumulative emissions per capita emission allowance

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 10004.,china Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China Institute of Policy and Management Chinese Academy of Sciences Beijing China Taishan University Taian China Graduate University of chinese academy of {2. Beijing 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

Features and distribution patterns of chinese endemic seed plant species

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Journal of Systematics and Evolution 2011年第2期49卷 81-94页

作者： 1,2.3.Ji-Hong HUANG 1,4.Jian-Hua CHEN 5 Jun-Sheng YING 1 Ke-Ping MA 1 (State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, chinese academy of {2., beijing 100093. china) 2.(Graduate University of chinese academy of {2., beijing 10004., china) 3.(Center for Documentation and Information, Institute of Botany, chinese academy of {2., beijing 100093. china) 4.(Zhejiang Normal University, Jinhua 3.0}004. china) 5 (Research Center of Systematic and Evolutionary Botany, Institute of Botany, chinese academy of {2., beijing 100093. china) (State Key Laboratory of Vegetation and Environmental Change Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Graduate University of chinese academy of {2. Beijing 100049 China) (Center for Documentation and Information Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (Zhejiang Normal University Jinhua 321004 China) (Research Center of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China)

We compiled and identified a list of chinese endemic seed plant species based on a large number of published references and expert reviews. The characters of these seed plant species and their distribution patterns were described at length. china is rich in endemic seed plants, with a total of 14.93. species (accounting for 52.1% of its total seed plant species) belonging to 1584.genera and 191 families. Temperate families and genera have a significantly higher proportion of endemism than cosmopolitan and tropical ones. The most primitive and derived groups have significantly higher endemism than the other groups. The endemism of tree, shrub, and liana or vine is higher than that of total species; in contrast, the endemism of herb is lower than that of total species. Geographically, these chinese endemic plants are mainly distributed in Yunnan and Sichuan provinces, southwest china. Species richness and proportion of these endemic plants decrease with increased latitude and have a unimodal response to altitude. The peak value of proportion of endemism is at higher altitudes than that of total species and endemic species richness. The proportions of endemic shrub, liana or vine, and herb increase with altitude and have a clear unimodal curve. In contrast, the proportion of tree increases with altitude, with a sudden increase at ～4.00 m and has a completely different model. To date, our study provides the most comprehensive list of chinese endemic seed plant species and their basic composition and distribution features.

关键词： biodiversity conservation distribution pattern endemism flora of china seed plants.

The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science china(Technological sciences) 2010年第9期53卷 2521-2527页

作者： WANG Ke1,2.REN WeiJia1,WANG ShiDa1 & WENG LiJun3.1 academy of Opto-Electronics,chinese academy of sciences,beijing 100190,china 2.Graduate University of chinese academy of sciences,beijing 10004.,china 3.Lanzhou Institute of Chemical Physics,chinese academy of sciences,Lanzhou 73.000,china academy of Opto-Electronics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of {2. Beijing China Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou China

A solid lubricating material exposure experiment in space is one of the missions during the seventh manned spaceflight of china,and the key is to develop a device which can be fixed reliably outside of the orbital module and can be fetched conveniently by an astronaut during space *** solid lubricating material experiment device needs to be locked reliably in a vibrating and impacting environment during the launch phase,and should meet the requirement that it can be unlocked and fetched reliably by the astronaut wearing an extravehicular spacesuit via simple operations in orbit in an environment of high and low *** for the device we developed,the environmental characteristic of the mission was analyzed,the mechanical analysis and thermal analysis were carried out,and then a mechanism with functions of mechanical locking,structural self-locking and manual unlocking was *** device was verified by a sequence of experiments and was fetched by the astronaut during the flight of the Shenzhou-7 Spaceship.

关键词： manned spaceflight exposure experiment mechanism unlock

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 Bin1,3.4.. National Center for Gene Research, Shanghai Institutes for Biological {4., {3. {2. of {4., Shanghai 2.02.3. china 2. Graduate School of the {3. {2. of {4., {13. 10003., china 3. Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological {4., {3. {2. of {4., Shanghai 2.003.0} china National Center for Gene Research Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China Graduate School of the chinese academy of {2. Beijing China Institute of Plant Physiology and Ecology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 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 ?4.―+4. 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 ?4.―?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