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| 1 | Indian monsoon influences altitude effect of δ^(18)O in precipitation/river water on the Tibetan Plateau显示文摘The δ 18O variation in precipitation acquired from 28 stations within the network of Tibetan Observation and Research Platform(TORP)is studied, with the focus on the altitude effect of δ 18O in river water during monsoon precipitation in an effort to understand the monsoon influence on isotopic composition in annual river water. It is found that δ 18O in precipitation on the Plateau is influenced by different moisture sources, with significant Indian monsoon influence on δ 18O composition in plateau precipitation and river water. The δ 18O of water bodies in the monsoon domain is generally more depleted than that in the westerly domain, suggesting gradual rainout of southwesterly borne marine moisture in the course of long-distance transportation and lifting over the Himalayas. The lapse rate of δ 18O in river water with altitude is the largest during monsoon precipitation, due to the increased temperature vertical gradient over the southern Plateau region controlled by monsoon circulation. The combination of δ 18O in river water in monsoon (wet) and non-monsoon (dry) seasons shows a larger lapse rate than that in non-monsoon (dry) season alone. As the altitude effect of δ 18O in precipitation and river water on the Tibetan Plateau results from the combined effect of monsoon moisture supply and westerly moisture supply, the δ 18O composition and its altitude effect on the Plateau during monsoon seasons should be considered in the reconstruction of paleoelevation of the Tibetan Plateau. | YAO TanDong1,2, ZHOU Hang1,3 & YANG XiaoXin1,3 1 Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China 2 State Key Laboratory of Cryosphere Sciences, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China 3 Graduate University of Chinese Academy of Sciences, Beijing 100049, China | 2009 | Chinese Science Bulletin2009，54，16： | 28 |
| 2 | Ensemble projection of 1―3℃ warming in China显示文摘Studies on the influences of climate change on biogeochemical cycles and on the key vulnerabilities and the risk from climate change suggest that annual surface temperature rise of 1℃, 2℃ and 3℃ above the present level would lead to changes in extreme weather and climate events, food production, fresh water resources, biodiversity, human mortality, etc. Here two sets of simulations as performed with seventeen atmosphere-ocean general circulation models (AOGCMs) for the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC AR4), i.e. the model outputs from the 20th Century Climate in Coupled Models (20C3M) and from the Special Report on Emissions Scenarios (SRES) emission scenarios B1, A1B and A2, are used to analyze spatial and temporal characteristics of the above values in China over the 21st century. The results indicate that the rate of warming varies from region to region. The above values are reached much later (earlier) when emission amount is lower (higher), and spread of the time when the lower (higher) value is exceeded is narrower (wider) among the three scenarios. As far as the spatial pattern is concerned, the above values are crossed much earlier in northern China and the Tibetan Plateau with respect to the Yangtze-Huaihe River Valley and South China. | JIANG DaBang1,2,3, ZHANG Ying1,4 & SUN JianQi1,3 1 Nansen-Zhu International Research Centre, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China 2 Max Planck Institute for Biogeochemistry, Jena D-07745, Germany 3 Climate Change Research Center, Chinese Academy of Sciences, Beijing 100029, China 4 Graduate University of Chinese Academy of Sciences, Beijing 100049, China | 2009 | Chinese Science Bulletin2009，54，18： | 21 |
| 3 | Overexpression of P53 and its risk factors in esophageal cancer in urban areas of Xi′an显示文摘OverexpressionofP53anditsriskfactorsinesophagealcancerinurbanareasofXi′anQIAOGuiBin1,HANChengLong2,JIANGRenChao1,SUNChang?.. | QIAO GuiBin1, HAN ChengLong2, JIANG RenChao1, SUN ChangSheng3, WANG Yan3 and WANG YunJie3 | 1998 | World Journal of Gastroenterology1998，4，1： | 21 |
| 4 | In vitro production of TNFα,IL-6 and sIL-2R in Chinese patients with ulcerative colitis显示文摘InvitroproductionofTNFα,IL6andsIL2RinChinesepatientswithulcerativecolitisXIABing1,GUOHaiJian1,JBACrusius2,DENGChangSheng... | XIA Bing 1, GUO Hai Jian 1, JBA Crusius 2, DENG Chang Sheng 1, SGM Meuwissen 2 and AS Pena 2 | 1998 | World Journal of Gastroenterology1998，4，3： | 18 |
| 5 | Discovery and character of the Kunlun-Yellow River Movement显示文摘Based on geomorphological, tectonic and sedimentary data, a Kunlun Yellow River Tectonic Movement has been recognized in 1 10-0 60 Ma B.P. This tectonic movement, which leads to uplift of the Qinghai_Xizang (Tibet) Plateau from 1 500 to 3 000-3 500 m, is periodic, abrupt and changeable in the movement rate of uplifting and slide slipping. | CUI Zhijiu 1, WU Yongqiu 2,3 and LIU Gengnian 1 1. Department of Geography, Peking University, Beijing 100871, China 2. Open Research Laboratory of Environmental Changes and Natural Disaster of State Education Commission, Beijing 100875, China | 1998 | Chinese Science Bulletin1998，43，10： | 16 |
| 6 | Current status of gene therapy in gastroenterology显示文摘CurentstatusofgenetherapyingastroenterologyXUChangTai1andPANBoRong2Subjectheadingsgastroenterology;genetherapy;genetransfer... | XU Chang Tai 1 and PAN Bo Rong 2 | 1998 | World Journal of Gastroenterology1998，4，1： | 15 |
| 7 | Modeling the climate effects of different subregional uplifts within the Himalaya-Tibetan Plateau on Asian summer monsoon evolution显示文摘Considering the different uplifting time of different subregions of the Himalaya-Tibetan Plateau(TP),a series of numerical simulations have been conducted with the Community Atmosphere Model(CAM4) developed at the National Center for Atmospheric Research to explore the effects of the phased tectonic uplift of the Himalaya-TP on the evolution of Asian summer monsoons.The results show that the uplifts of the Himalaya and northern TP significantly affect the evolutions of South Asian summer monsoon and northern East Asian summer monsoon respectively.That is,the tectonic uplift of the Himalaya intensifies the South Asian summer monsoon circulation and increases the precipitation in South Asia,whereas the uplift of the northern TP intensifies the northern East Asian summer monsoon circulation and increases the precipitation in northern East Asia.Compared with previous simulations,current comparative analyses of modeling results for different subregional uplifts within the Himalaya-TP help deepen our understanding of the evolutionary history of Asian monsoons. | ZHANG Ran 1,JIANG DaBang 1,2,3,LIU XiaoDong 4 & TIAN ZhiPing 2,5 1 Climate Change Research Center,Chinese Academy of Sciences,Beijing 100029,China 2 Nansen-Zhu International Research Centre,Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China 3 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,Chinese Academy of Sciences,Beijing 100029,China 4 State Key Laboratory of Loess and Quaternary Geology,Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,China 5 Graduate University of Chinese Academy of Sciences,Beijing 100049,China | 2012 | Chinese Science Bulletin2012，57，35： | 14 |
| 8 | Miocene Bahean stratigraphy in the Longzhong Basin, northern central China and its implications in environmental change显示文摘Fossil mammal-riched Neogene strata are widely distributed in the southeast corner of the huge Longzhong Basin at Tianshui, Gansu Province, northern central China. Hipparion weihoense, a typical member of late Middle Miocene Bahean stage, was recently excavated at Yaodian along a well-exposed outcrop. Owing to the importance of the Bahean stage in the mammalian evolution and its potential for environmental change, we suggested a name of Yaodian Formation for the stratigra- phy, which is correlated to the Bahe Formation at Lantian, Shaanxi. High resolution paleomagnetic dating of the section shows that the Yaodian Formation covers the period between 11.67 Ma and 7.43 Ma, with the site bearing Hipparion weihoense being estimated at about 10.54―10.30 Ma, providing first magnetostratigraphic chronology for the Bahean Stage. The Yaodian Formation consists of fluvial channel deposits (11.67―10.40 Ma) at the bottom, floodplain deposits in the middle (10.40―9.23 Ma) and shallow lake sediments at the top (9.23―7.43 Ma). This upward fining sequence suggests that the relief in nearby mountain ranges such as West Qinling to the south and Huajia Ling to the north was greatly reduced after long-term denudation, fluvial transport capacity was low, and finally the drainage system was disintegrated, replaced with broad-shallow lakes in which only fine sediments like mud and marlite were deposited, indicating an old stage of development of a planation surface. A remarkable shift in ecology and climatic environment was found at 7.4―7.7 Ma when paleoclimate changed from early warm humid to late dry as indicated by sedimentary facies changed from early shallow lake sequence to late eolian red clays and a former coniferous-deciduous mixed forest was replaced by grassland, leading to great growth of Hipparion Fauna of Baodean stage in the region. Therefore, it is estimated that the present high relief of Qinling and drainage pattern did not come into being until Late Pliocene in response to intensive neotectonism and climate change. | LI Jijun1,2, ZHANG Jun1, SONG Chunhui1, ZHAO Zhijun2, ZHANG Yong1, WANG Xiuxi 1, ZHANG Jianming1 & CUI Qiaoyu1 1. Key Laboratory of Western China’s Environmental Systems (Ministry of Education) & College of Earth and Environment Sciences, Lanzhou University, Lanzhou 730000, China 2. Jiangsu Key Laboratory of Environmental Change and Ecological Construction & College of Geography, Nanjing Normal University, Nanjing 210097, China | 2006 | Science China Earth Sciences2006，49，12： | 12 |
| 9 | Effects of endotoxin on expression of ras, p53 and bcl-2 oncoprotein in hepatocarcinogenesis induced by thioacetamide in rats显示文摘Efectsofendotoxinonexpressionofras,p53andbcl2oncoproteininhepatocarcinogenesisinducedbythioacetamideinratsYANGJinMing1,HAN... | YANG Jin Ming 1, HAN De Wu 1, LIANG Quan Chen 2, ZHAO Jia Li 2, HAO Su Yuan 1, MA Xue Hui 1 and ZHAO Yuan Chang 1 | 1997 | World Journal of Gastroenterology1997，3，4： | 11 |
| 10 | Primary scientific results of Chang'E-1 lunar mission显示文摘The strategic plan for the development of the unmanned Chinese Lunar Exploration Program is characterized by three distinct stages: 'orbiting around', 'landing on' and 'returning from' the Moon. The first Chinese lunar probe, Chang'E-1, which was successfully launched on October 24th, 2007 at Xichang Satellite Launch Center, and guided to crash on the Moon on March 1st, 2009, at 52.36°E, 1.50°S, in the north of Mare Fecunditatis, is the first step towards the 'orbiting around' stage. The Chang'E-1 mission lasted 495 days, exceeding the expected life-span by about four months. A total of 1.37 TB raw data was received from Chang'E-1. It was then processed into 4 TB scientific data products at various levels. Many scientific results have been obtained by analyzing these data, including especially the 'global lunar image from the first Chinese lunar explora- tion mission'. All scientific goals of Chang'E-1 have been achieved. It provides much useful materials for further advances of lunar sciences and planetary chemistry. Meanwhile, these results will serve as a firm basis for future Chinese lunar missions. | OUYANG ZiYuan1,2, LI ChunLai1, ZOU YongLiao1, ZHANG HongBo1, Lü Chang1, LIU JianZhong1, LIU JianJun1, ZUO Wei1, SU Yan1, WEN WeiBin1, BIAN Wei1, ZHAO BaoChang3, WANG JianYu4, YANG JianFeng3, CHANG Jin5, WANG HuanYu6, ZHANG XiaoHui7, WANG ShiJin7, WANG Min1, REN Xin1, MU LingLi1, KONG DeQing1, WANG XiaoQian1, WANG Fang1, GENG Liang1, ZHANG ZhouBin1, ZHENG Lei1, ZHU XinYing1, ZHENG YongChun1, LI JunDuo1, ZOU XiaoDuan1, XU Chun1, SHI ShuoBiao1, GAO YiFei1 & GAO GuanNan1 1 National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012, China 2 Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550002, China 3 Xi’an Institute of Optics and Precision Mechanics, Chinese Academy of Sciences, Xi’an 710119, China 4 Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China 5 Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China 6 Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China 7 Center for Space Science and Applied Research, Chinese Academy of Sciences, Beijing 100190, China | 2010 | Science China Earth Sciences2010，53，11： | 11 |
| 11 | Influence of differential settlement on pavement structure of widened roads based on large-scale model test显示文摘This study introduced at first the background of numerous highway widening projects that have been developed in recent years in China.Using a large ground settlement simulator and a fiber Bragg grating (FBG) strain sensor network system,a large-scale model test,with a similarity ratio of 1:2,was performed to analyze the influence of differential settlement between new and old subgrades on pavement structure under loading condition.The result shows that excessive differential settlement can cause considerable tensile strain in the pavement structure of a widened road,for which a maximum value (S) of 6 cm is recommended.Under the repetitive load,the top layers of pavement structure are subjected to the alternate action of tensile and compressive strains,which would eventually lead to a fatigue failure of the pavement.However,application of geogrid to the splice between the new and the old roads can reduce differential settlement to a limited extent.The new subgrade of a widened road is vulnerable to the influence of dynamic load transferred from the above pavement structures.While for the old subgrade,due to its comparatively high stiffness,it can well spread the load on the pavement statically or dynamically.The test also shows that application of geogrid can effectively prevent or defer the failure of pavement structure.With geogrid,the modulus of resilience of the subgrade is increased and inhomogeneous deformation can be reduced;therefore,the stress/strain distribution in pavement structure under loading condition becomes uniform.The results obtained in this context are expected to provide a helpful reference for structural design and maintenance strategy for future highway widening projects. | Xiaolin Weng1,2,Wei Wang3 1 Key Laboratory for Special Area Highway Engineering of Ministry of Education,Chang’an University,Xi’an,710064,China 2 CCCC First Highway Consultants Co.,Ltd.,Xi’an,710068,China 3 Henan Vocational and Technical College of Communications,Zhengzhou,450005,China | 2011 | Journal of Rock Mechanics and Geotechnical Engineering2011，3，1： | 11 |
| 12 | Unified solutions for stresses and displacements around circular tunnels using the Unified Strength Theory显示文摘The unified solutions are presented for stresses and displacements around a circular tunnel subjected to a hydrostatic stress field.The rock mass is assumed to be elastic-brittle-plastic and governed by the Unified Strength Theory.The displacements are obtained accounting for three different definitions for elastic strains and different Young's modulus in the plastic zone.The unified solutions obtained in this paper are especially versatile in reflecting the intermediate principal stress effect to different extents for different materials.The conventional solutions,based on the Mohr-Coulomb failure criterion and the Generalized Twin Shear Stress yield criterion,are special cases of the present unified solutions.The new unified solutions can compare with those computed by the latest generalized Hoek-Brown failure criterion.The results obtained demonstrate the importance of the intermediate principal stress influence for the stresses and displacements analysis.The effects of different definitions for elastic strains and different Young's modulus in the plastic zone on the displacements are significant. | ZHANG ChangGuang1,WANG JiangFeng2 & ZHAO JunHai3 1 Department of Geotechnical Engineering,Tongji University,Shanghai 200092,China 2 North China Institute of Water Conservancy and Hydroelectric Power,Zhengzhou 450011,China 3 School of Civil Engineering,Chang’an University,Xi’an 710061,China | 2010 | Science China(Technological Sciences)2010，53，6： | 8 |
| 13 | Study on the drug resistance and the binding mode of HIV-1 integrase with LCA inhibitor显示文摘Human immunodeficiency virus type 1 (HIV-1) integrase (IN) is an essential enzyme in the lifecycle of this virus and also an important target for the study of anti-HIV drugs. The binding mode of the wild type IN core domain and its G140S mutant with L-Chicoric acid (LCA) inhibitor were investigated by using multiple conformation molecular docking and molecular dynamics (MD) simulation. Based on the binding modes, the drug resistance mechanism was explored for the G140S mutant of IN with LCA. The results indicate that the binding site of the G140S mutant of IN core domain with LCA is different from that of the core domain of the wild type IN, which leads to the partial loss of inhibition potency of LCA. The flexibility of the IN functional loop region and the interactions between Mg2+ ion and the three key residues (i.e., D64, D116, E152) stimulate the biological operation of IN. The drug resistance also lies in several other important effects, such as the repulsion between LCA and E152 in the G140S mutant core domain, the weakening of K159 binding with LCA and Y143 pointing to the pocket of the G140S mutant. All of the above simulation results agree well with experimental data, which provide us with some helpful information for designing the drug of anti-HIV based on the structure of IN. | HU JianPing1,2, CHANG Shan1, CHEN WeiZu1 & WANG CunXin1 1 College of Life Science and Bioengineering, Beijing University of Technology, Beijing 100022, China 2 Department of Chemistry & Life Sciences, Leshan Normal University, Leshan 614004, China | 2007 | Science China Chemistry2007，50，5： | 7 |
| 14 | Repair effect of diabetic ulcers with recombinant human epidermal growth factor loaded by sustained-release microspheres显示文摘In this study the w/o/w extraction–evaporation technique was adopted to prepare poly(lactic-co-glycolic acid) (PLGA) microspheres loading recombinant human epidermal growth factor (rhEGF). The micro-spheres were characterized for morphology by transmission electron microscopy (TEM) and particle size distribution. The release performances, the proliferation effects and therapeutic effects of rhEGF-loaded PLGA microspheres were all studied. The results showed that these spherical micro-spheres had a narrow size distribution and a high drug encapsulation efficiency (85.6%). RhEGF-loaded microspheres enhanced the growth rate of fibroblasts and wound healing more efficiently than pure rhEGF. The number of the proliferating cell nuclear antigen (PCNA) in the epidermis layer with the mi-crosphere treatment was significantly larger than those of the control groups. Overall locally sustained delivery of rhEGF from biodegradable PLGA microspheres may serve as a novel therapeutic strategy for diabetic ulcer repair. | DONG XiaoQing1, XU Jun2, WANG WeiCai1, Luo Hao1, LIANG XiaoFei1, Zhang Lei1, Wang HanJie1, Wang PengHua2 & CHANG Jin1 1 Institute of Nanobiotechnology, School of Materials Science and Engineering, Tianjin University, Tianjin 300072, China 2 Department of Diabetic Foot, Tianjin Medical University Metabolic Disease Hospital, Tianjin 300070, China | 2008 | Science China(Life Sciences)2008，51，11： | 7 |
| 15 | Responses of soil respiration in non-growing seasons to environmental factors in a maize agroecosystem,Northeast China显示文摘Based on continuous three-year measurements (from 2004 to 2007) of eddy covariance and related environmental factors, environmental controls on variation in soil respiration (Rs) during non-growing season were explored in a maize agroecosystem in Northeast China. Our results indicated that during non-growing seasons, daily Rs was 1.08-4.08 g CO2 m-2 d-1, and the lowest occurred in late November. The average Rs of non-growing season was 456.06 ± 20.01 g CO2 m-2, accounting for 11% of the gross primary production (GPP) of the growing season. Additionally, at monthly scale, the lowest value of Rs appeared in January or February. From the beginning to the end of non-growing season, daily Rs tended to decrease first, and then increase to the highest. There was a significant quadratic curve relationship between Rs and soil temperature at 10 cm depth when soil temperature was more than 0°C (P<0.001), with the explaining ratio of 38%-70%. When soil water content was more than 0.1 m3 m-3, soil moisture at 10 cm depth was significantly parabolically correlated with Rs (P<0.001), explaining the rate of 18%-60%. Based on all the data of soil temperature of more than 0°C, a better model for Rs was established by coupling soil temperature and moisture, which could explain the rate of up to 53%-79%. Meanwhile, the standard error of regression estimation between the values of prediction and observation for Rs could reach 2.7%-11.8%. Rs in non-growing season can account for 22.4% of Rs in growing season, indicating that it plays a critical role in assessing the carbon budget in maize agroecosystem, Northeast China. | LI RongPing1,2,3, ZHOU GuangSheng1,4 & WANG Yu1,3 1 State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China 2 Institute of Atmospheric Environment, China Meteorological Administration, Shenyang 110016, China 3 Graduate University of Chinese Academy of Sciences, Beijing 100049, China 4 Chinese Academy of Meteorological Sciences, Beijing 100081, China | 2010 | Chinese Science Bulletin2010，55，24： | 7 |
| 16 | Turbulent intensity and its similarity function over an Inner Mongolian grassland during spring显示文摘Macroscopic reason for the development of turbulences in fluid is the conjunction action of velocity and temperature shears. We use the 2008 spring flux observations in the surface layer over Inner Mongolian grassland, obtain the similarity functions of turbulent intensity under different stratification stability conditions, and calculate the clear day turbulent intensity in the spring, which is then analyzed and compared with the observed values of turbulent intensity. The results show that in the Inner Mongolian grassland, under the condition of spring unstable stratification of the surface layer, dependence of the similarity function of turbulent intensity on stratification stability follows a '2/3 power law'. The structural function is a constant under the neutral stratification condition, and complicated under the stable condition. The calculated turbulent intensity has a close correlation with the observed one, which verifies the accuracy of the similarity functions and the suitability of the theorem of turbulent intensity in the grassland region. | YUE Ping1,2,3, NIU ShengJie2, HU YinQiao4 & ZHANG Qiang1 1 Key Laboratory of Arid Climate Change and Reducing Disaster of Gansu Province, Key Laboratory of Arid Climate Change and Reducing Disaster of CMA, Institute of Arid Meteorology, CMA, Lanzhou 730020, China 2 Nanjing University of Information Science and Technology, Nanjing 210044, China 3 Zhangye National Meteorological Observatory, Zhangye 734000, China 4 Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Science, Lanzhou 730000, China | 2010 | Science China Earth Sciences2010，53，5： | 7 |
| 17 | Pollen assemblage characteristics of lakes in the monsoon fringe area of China显示文摘This paper presents the pollen assemblages from 108 surface sediment samples from 4 lakes(the Lake Daihai,Lake Hongjiannao,Lake Hulunnao and Lake Duikounao) in the monsoon fringe area of China.The herb pollen taxa Artemisia,Chenopodiaceae,Poaceae and Compositae are the major components of pollen assemblages of the 4 lakes and Pinus,Betula,Quercus,Ulmus,Populus,Ostryopsis and Elaeagnaceae are frequently presented,which reflect regional and local vegetation well.The mean similarity coefficients for samples from the Lake Daihai,Lake Hongjiannao,Lake Hulunnao and Lake Duikounao are 0.66 ± 0.17,0.71 ± 0.11,0.73 ± 0.12 and 0.67 ± 0.12 respectively,so pollen assemblages are relatively consistent in each lake,which shows that focusing and mixing effects have occurred before and after pollen deposition.However,pollen assemblages do differ between sampling sites in each lake.The largest difference is seen in the Lake Daihai,followed by the Lake Duikounao,Lake Hulunnao and Lake Hongjiannao(The mean Euclidean distance is 20.09 ± 11.11,11.22 ± 3.64,10.67 ± 4.03 and 8.44 ± 4.51 respectively).These differences are possibly caused by the differences of focusing and mixing effects,pollen source areas,drainage areas and regional vegetation compositions.The Lake Daihai and Lake Hongjiannao have water deeper than 5 m and strong re-suspension,focusing and mixing effects occur in the lakeshore and shallow water areas,where pollen concentrations are lower than in deeper lake areas.In the Lake Hulunnao and Lake Duikounao,with depths less than 5 m,re-suspension and mixing effects are obvious across the whole lake area,so pollen assemblages and pollen concentra-tions are more consistent among sampling sites in each lake.Comparison between the lake samples and samples from the inflowing river reveals that wind is primary pollen transportation force in the Lake Hongjiannao,where the consistency of pollen assemblage is conspicuous,while there is greater variation in lakes where pollen input is dominated by waterborne sources. | TIAN Fang1,2,XU QingHai1,2,3,LI YueCong1,2,CAO XianYong1,2,WANG XueLi1,2 & ZHANG LiYan1,2 1 College of Resources and Environmental Sciences,Hebei Normal University,Shijiazhuang 050016,China 2 Hebei Key Laboratory of Environmental Change and Ecological Construction,Shijiazhuang 050016,China 3 Key Laboratory of Western China’s Environmental System(Ministry of Education),Lanzhou University,Lanzhou 730000,China | 2008 | Chinese Science Bulletin2008，53，21： | 7 |
| 18 | Nonholonomic mapping theory of autoparallel motions in Riemann-Cartan space显示文摘The method of nonholonomic mapping is utilized to construct a Riemann-Cartan space embedded into a known Riemann-Cartan space,which includes two special cases that a Weitzenbck space and a Riemann-Cartan space are respectively embedded into a Euclidean space and a Riemann space.By means of this mapping theory,the nonholonomic corresponding relation between the autoparallels of two Riemman-Cartan spaces is investigated.In particular,an autoparallel in a Riemann-Cartan space can be mapped into a geodesic line in a Riemann space and an autoparallel in Weitzenbck space be mapped into a geodesic line in Euclidean space.Based on the Lagrange-d'Alembert principle,the equations of motion for dynamical systems in Riemman-Cartan space should be autoparallel equations of the space.As applications,the problem of autoparallel motion of spinless particles,Chaplygin's nonholonomic systems and a rigid body rotating with a fixed point are investigated in space with torsion. | GUO YongXin1,LIU Chang2,WANG Yong3,LIU ShiXing1 & CHANG Peng2 1 College of Physics,Liaoning University,Shenyang 110036,China 2 School of Aerospace Engineering,Beijing Institute of Technology,Beijing 110081,China 3 School of Basic Medical Science,Guangdong Medical College,Dongguan 523808,China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，9： | 6 |
| 19 | Record of environmental change by α-cellulose δ ^(13)C of sphagnum peat at Shennongjia,4000―1000 aBP显示文摘The Dajiuhu Basin at Shennongjia,located within typical East Asian Monsoon region,preserves a sub-alpine sphagnum peat deposition in its central area.The topmost 120 cm of the peat covers the last 4000 years according to AMS 14C dating of pollen concentration.Carbon isotope of α-cellulose,extracted from sphagnum peat,provides a quantitative reconstruction of atmospheric relative humidity,based on transfer functions of C3 plants carbon isotopic fractionation equation and the bryophyte photosynthesis CO2 absorption rate equation.δ 13C,TOC and C/N variations reveal that the Dajiuhu area has experienced a long-term tendency to dry during 4000―1000 aBP,with a major transition happening around 3000 aBP.Four relative dry events are identified at 3400―3200,3000―2600,2200―2000 and 1600―1400 aBP,respectively,corresponding to those climate events documented in many global records.Three periodicities,664 a,302 a and 277 a enclosed in the atmospheric humidity of Dajiuhu are correlated to the cycles of solar activities.The weakening of East Asia summer monsoon during this period registered in the Dajiuhu peat is consistent with the synchronous weakening of Indian Monsoon.This trend may be attributed to gradual decrease of Northern Hemispheric summer solar insolation and the consequently southward migration of Intertropical Convergent Zone(ITCZ). | ZHU Yun1,2,CHEN Ye1,2,ZHAO ZhiJun1,2,XIAO JiaYi1,2,ZHANG MaoHeng1,2,SHU Qiang1,2 & ZHAO HongYan1,2 1 College of Geography Science,Nanjing Normal University,Nanjing 210046,China 2 Jiangsu Key Laboratory of Environmental Change and Ecological Construction,Nanjing 210046,China | 2009 | Chinese Science Bulletin2009，54，20： | 6 |
| 20 | Disassembly intermediates of RbsD protein remain oligomeric despite the loss of an intact secondary structure显示文摘Many proteins exist as homo-oligomers in living organisms wherein the change of oligomeric status apparently serves as an effective means for modulating their biological activities. We have previously reported that the homo-decameric RbsD from Escherichia coli undergoes stepwise disassembly and non-stepwise reassembly. Here the structural status of the urea-induced RbsD disassembly intermediates was examined, mainly using urea-containing polyacrylamide gel electrophoresis and chemical cross-linking. Such intermediates were found to remain oligomeric while losing their intact secondary structures. Such disassembly intermediates were able to effectively refold when the concentration of the urea denaturant was reduced to a lower level, or to refold/reassemble into the native decamers when urea was completely removed, as detected by non-denaturing polyacrylamide gel electrophoresis. These novel observations strongly suggest that the assembly of oligomeric proteins may occur before the completion of subunit folding. | FENG YongJun1, ZHANG Meng2, HU MingXi1, ZHENG Jie1, JIAO WangWang2 & CHANG ZengYi2 1 School of Life Science, Beijing Institute of Technology, Beijing 100081, China 2 School of Life Sciences, National Laboratory of Protein Engineering and Plant Genetic Engineering, Center for Protein Science, Peking University, Beijing 100871, China | 2009 | Science China(Life Sciences)2009，52，11： | 5 |
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