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Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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Science china Earth Sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2, XU Ran1, TANG Zhongdao1, SI Yuanlan3.& LI Baohua4.1. Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources, china University of Geosciences, Wuhan 4.0}074. china 2. Institute of Resources & Environments, Henan Polytechnic University, Jiaozuo 4.4.03. china 3. {3. of Computer Science, South-Central University for Nationalities, Wuhan 4.0}074. china 4. Laboratory of Marine Geology, Tongji University, Shanghai 200092, china Faculty of Earth Science and State Key Laboratory of Geological Processes and Mineral Resources china University of Geosciences Wuhan china Institute of Resources & Environments Henan Polytechnic University Jiaozuo china department of Computer Science South-Central University for Nationalities Wuhan china Laboratory of Marine Geology Tongji University Shanghai china

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13.carb and δ 13.kerogen) from +0.4.0}(‰ V-PDB) to +3.54.(‰ V-PDB) and from ?29.3. (‰ V-PDB) to ?24.14.(‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3.X 15%)) values from 0.015 to 0.14., TOC values from 0.02% to 0.21%, V/Cr values from 0.3.to 2.0, Sr/Ba values from 3.20 to 4..50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, South china, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2, climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, South china.

Optimal reactions for the synthesis of superheavy nucleus ^(270)Hs

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3.& BAO Jingdong1,2 1. Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing normal University, Beijing 100875, china 2. Physics department, Beijing normal University, Beijing 100875, china 3. china Institute of Atomic Energy, Beijing 1024.3. china Key Laboratory of Beam Technology Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China Physics department Beijing Normal University Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China

The superheavy nucleus 270Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 24.Cm(26Mg,4.)270Hs, 24.Pu(3.Si,4.)270Hs, 23.U(3.S,4.)270Hs and 226Ra(4.Ca,4.)270Hs using a two-parameter Smoluchowski equation. It is found from our results that 226Ra(4.Ca,4.)270Hs and 23.U(3.S,4.)270Hs are two optimal reactions for the synthesis of the superheavy nucleus 270Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

河南省高校体育教师职业倦怠状况及其与职业自我概念的关系

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体育学刊 2008年第7期15卷 63-66页

作者：郝明周口师范学院公体部河南周口466000

对河南省高校体育教师职业倦怠状况及其与职业自我概念的关系进行了研究。结果表明:1)河南省高校体育教师的职业倦怠程度整体上并不严重,情绪衰竭相对突出。2)体育教师的职业倦怠与职业自我概念存在显著相关。3.职业自我概念中工作满意... 详细信息

对河南省高校体育教师职业倦怠状况及其与职业自我概念的关系进行了研究。结果表明:1)河南省高校体育教师的职业倦怠程度整体上并不严重,情绪衰竭相对突出。2)体育教师的职业倦怠与职业自我概念存在显著相关。3.职业自我概念中工作满意、师生关系和人际知觉对职业倦怠有显著的预测作用。

关键词：体育教师职业倦怠职业自我概念河南省

Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2,3., ZHOU Wancun 1 ,ZHOU Jieming 4., ZHU Mingcang 3.5 1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences , Chengdu 61004., Sichuan, china 2. Graduate University of Chinese Academy of Sciences, Beijing 10004., china 3. Sichuan Institute of Land Resource Management, Chengdu 61004., Sichuan , china 4. {3. of Resources and Environment Science, Sichuan normal University , Chengdu 610061, Sichuan, china 5. College of Information Engineering, Chengdu University of Technology, Chengdu 610059, Sichuan, china Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China Graduate University of Chinese Academy of Sciences Beijing China Sichuan Institute of Land Resource Management Chengdu Sichuan China department of Resources and Environment Science Sichuan Normal University Chengdu Sichuan China College of Information Engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2002; the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 13.Cs technique

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Chinese Science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. Key Laboratory of Environmental Change and Natural Disaster, the Ministry of Education of china, Beijing normal University, Beijing 100875, china 2. Institute of Desert Research, Chinese Academy of Sciences, Lanzhou 73.000, china 3. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 61004., china 4. department of Physics, Sichuan Union University, Chengdu 61004., china Key Laboratory of Environmental Change and Natural Disaster the Ministry of Education of China Beijing Normal University Beijing China Institute of Desert Research Chinese Academy of Sciences Lanzhou China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China department of Physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-13. (13.Cs) associated with the nuclear weapon tests during the 1950s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 13.Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 13.Cs reference inventories of 982.11 and 2 3.6.04.Bq · m-2 wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 13.Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 4. years have been revealed, i.e. the shrub coppicedunes (S1) and semi-fixed dunefields (S3. experienced the alternation of erosion and deposition,while the grasslands (S4. S6 and S7) and dry farmlands (S5) suffered erosion only. By using 13.Csmodel, the average wind erosion rates for shrub coppice

关键词： 13.Cs technique Qinghai-Tibetan Plateau wind erosion.

X-ray spectra induced by ^(12.)Xe^(q+) impacting the metal surface

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Science china(Physics,Mechanics & Astronomy) 2008年第1期51卷 82-89页

作者： ZHANG XiaoAn 1,2 ,XIAO GuoQing 1 ,YANG ZhiHu 1 ,CHEN XiMeng 3.,ZHAO YongTao 1 , LI FuLi 4.,WANG Li 1,2 ,CUI Ying 3.,ZHANG HongQiang 3.&ZHAN WenLong 1 1Institute of Modern Physics,Chinese Academy of Sciences,Lanzhou 73.000,{4. 2department of Physics,Xianyang normal University,Xianyang 7{3.00,{4. 3.1} of Modern Physics,Lanzhou University,Lanzhou 73.000,{4. 4.5} of Applied Physics,Xi’an Jiaotong University,Xi’an 71004.,{4. 1. Institute of Modern Physics Chinese Academy of Sciences Lanzhou 730000 China 2. department of Physics Xianyang Normal University Xianyang 712000 China 3. department of Modern Physics Lanzhou University Lanzhou 730000 China 4. department of Applied Physics Xi’an Jiaotong University Xi’an 710049 China

Using the slow highly charged ions 12. Xe q+ (q=25,26,27;initial kinetic T0≤4.65 keV/a.u.)to impact Au surface,the Au atomic Mαcharacteristic X-ray spectrum is *** result shows that as long as the charge state of projectile is high enough,the heavy atomic characteristic X-ray can be effectively excited even though the incident beam is very weak(nA magnitude),and the X-ray yield per ion is in the order of 10-8and increases with the kinetic energy and potential energy of *** measuring the Au Mα-X-ray spectra,Au atomic N-level lifetime is estimated at about 1.3.×10-18s based on Heisenberg uncertainty relation.

关键词： slow highly charged ions characteristic X-ray level lifetime

Efficient estimation for additive hazards regression with bivariate current status data

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Science china Mathematics 2012年第4期55卷 763-774页

作者： TONG XingWei 1,,HU Tao 2 & SUN JianGuo 3.4.1 School of Mathematical Sciences,Beijing normal University,Beijing 100875,china 2 School of Mathematical Sciences,Capital normal University,Beijing 10004.,china 3.School of Mathematics,Jilin University,Changchun 13.012.china 4.department of Statistics,University of Missouri,Columbia,MO 65211,USA 1. School of Mathematical Sciences Beijing Normal University Beijing 100875 China2. School of Mathematical Sciences Capital Normal University Beijing 100048 China3. School of Mathematics Jilin University Changchun 130012 China4. Department of Statistics University of Missouri Columbia MO 65211 USA

This paper discusses efficient estimation for the additive hazards regression model when only bivariate current status data are available. Current status data occur in many fields including demographical studies and tumorigenicity experiments （Keiding, 1991; Sun, 2006） and several approaches have been proposed for the additive hazards model with univariate current status data （Linet M., 1998; Martinussen and Scheike, 2002）. For bivariate data, in addition to facing the same problems as those with univariate data, one needs to deal with the association or correlation between two related failure time variables of interest. For this, we employ the copula model and an efficient estimation procedure is developed for inference. Simulation studies are performed to evaluate the proposed estimates and suggest that the approach works well in practical situations. An illustrative example is provided.

关键词： bivariate current status data copula model counting processes efficient estimation joint survivalfunction

Synthesis of superheavy nuclei with ^(23.)U target

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1482-1488页

作者： LIU ZuHua1,3.& BAO JingDong2,4.1 Key Laboratory of Beam Technology and Material Modification of Ministry of Education,Beijing normal University,Beijing 100875,china 2 department of Physics,Beijing normal University,Beijing 100875,china 3.5} Institute of Atomic Energy,Beijing 1024.3.china 4.Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 73.000,china Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China department of Physics Beijing Normal University Beijing 100875 China china Institute of Atomic Energy Beijing 102413 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The production of superheavy nuclei with Z=108-116 via hot fusion reactions of the neutron-rich projectiles with 23.U target is systematically *** results show that the production cross sections of superheavy nuclei do not decrease monotonously as the atomic number Z *** cross sections of the superheavy nuclei at Z = 112.and 115 are enhanced as compared with the whole Z-trend in synthesis of the superheavy nuclei,which clearly illustrates that the reactions with large negative Q-value and shell correction are more favorable to synthesize superheavy nuclei.

关键词： superheavy nuclei fusion reaction cross section 23.U target

LOD score exclusion analyses for candidate disease susceptibility genes using case-parents design

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Progress in Natural Science:Materials International 2006年第1期16卷 30-38页

作者： DENG Hongwen1,2,3.and GAO Guimin2,4.(1.Laboratory of Molecular and Statistical Genetics, College of Life Sciences, Hunan normal University, Changsha 4.0081, china 2.Osteoporosis Research Center, Creighton University Medical Center, Omaha NE 6813., USA 3. department of Biomedical Sciences, Creighton University, Omaha NE 6813., USA 4. Virginia Bioin format ics Institute and department of Statistics, Virginia Polytechnic Institute and State University, Blacksburg VA 24.61-03.5, USA) [a]Laboratory of Molecular and Statistical Genetics College of Life Sciences Human National University Changsha China [b]Osteoporosis Research Center Creighton University Medical Center Omaha NE USA [c]department of Biomedical Sciences Creighton University Omaha NE USA [d]Virginia Bioinformatics Institute and department of Statistics Virginia Polytechnic Institute and State University Blacksburg VA USA

The focus of almost all the association studies of candidate genes is to test for their importance. We recently developed a LOD score approach that can be used to test against the importance of candidate genes for complex diseases and quantitative traits in random samples. As a complementary method to regular association analyses, our LOD score approach is powerful but still affected by the population admixture, though it is more conservative. To control the confounding effect of population heterogeneity, we develop here a LOD score exclusion analysis using case-parents design, the basic design of the transmission disequilibrium test (TDT) approach that is immune to population admixture. In the analysis, specific genetic effects and inheritance models at candidate genes can be analyzed and if a LOD score is ≤ - 2. 0, the locus can be excluded from having an effect larger than that specified. Simulations show that this approach has reasonable power to exclude a candidate gene having small genetic effects if it is not a disease susceptibility locus (DSL) with sample size often employed in TDT studies. Similar to association analyses with the TDT in nuclear families, our exclusion analyses are generally not affected by population admixture. The exclusion analyses may be implemented to rule out candidate genes with no or minor genetic effects as supplemental analyses for the TDT. The utility of the approach is illustrated with an application to test the importance of vitamin D receptor (VDR) gene underlying the differential risk to osteoporosis.

关键词： association studies candidate genes case-parents design disease susceptibility locus exclusion mapping LOD score.