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Thresholds of geographic environmental elements in sediment yield of drainage basins

Science China Earth sciences 2005年第2期48卷 230-240页

作者： CHEN Hao, ZHOU Jinxing, CAI Qiangguo, LU Zhongchen & LI Zhongyan Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, China Institute of forestry Science, Chinese Academy of forestry Science, Beijing 100091, China Research Center for Eco-Environment sciences, Chinese Academy of sciences, Beijing 100085, China Computing Institute of Science and Engineering, North China Electric Power university, Beijing 102206, China 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Institute of forestry Science Chinese Academy of Forestry Science 100091 Beijing China 3. Research Center for Eco-Environment sciences Chinese Academy of Sciences 100085 Beijing China 4. Computing Institute of Science and Engineering North China Electric Power University 102206 Beijing China

Threshold of environmental elements in drainage basin sediment yield refers to, under effect of climate, underlying surface and human activity, a turning point of abrupt changes in drainage sediment yield related to environmental element characteristics. Previous studies on threshold of sediment yield of relevant drainage basins were mainly concentrated on impact of natural zones with a few researches on impact of other environmental elements. Particularly studies on compound environmental element threshold in drainage basin sediment yield remain blank today. Studies indicate that sediment yield in drainage basins is affected by compound interactions and complex actions. Based on single element analysis, the present paper gives quantitatively compound threshold of environmental elements affecting sediment yield of the drainage basin between Hekouzhen and Tongguan in the middle Yellow River by the method of multi-variant, polynomial formula regression analysis.

关键词： middle Yellow River, environmental element, sediment, sediment delivery mudule, threshold.

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Diversity and ecological distribution of endophytic fungi associated with medicinal plants

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Science China(Life sciences) 2008年第8期51卷 751-759页

作者： SUN JianQiu1,2,3, GUO LiangDong1, ZANG Wei2,3, PING WenXiang4.& CHI DeFu3 1 Systematic Mycology and Lichenology Laboratory, Institute of Microbiology, Chinese Academy of sciences, Beijing 100101, China 2 College of Life Science and Engineering, Qiqihar university, Qiqihar 161006, China 3 College of forestry, Northeast forestry university, Harbin 15004., China 4.College of Life Science, Heilongjiang university, Harbin 150080, China 1. Systematic Mycology and Lichenology Laboratory Institute of Microbiology Chinese Academy of Sciences Beijing 100101 China 2. College of Life Science and Engineering Qiqihar University Qiqihar 161006 China 3. College of forestry Northeast Forestry University Harbin 150040 China 4. College of Life Science Heilongjiang University Harbin 150080 China

A total of 973 isolates of endophytic fungi were recovered from 114. tissue fragments of the six me-dicinal plant species belonging to 4.families collected in the Beijing Botanical Garden. Of these isolates 778 sporulated and were identified into 21 taxa by morphological characteristics. Among the taxa 11 belonged to Coelomycetes, 6 to Ascomycetes, and 4.to Hyphomycetes. Various numbers of endophytic fungi (5―8 taxa) were obtained from each plant. alternaria alternata was the dominant species in the 6 plants, and Microsphaeropsis conielloides was also dominant in Eucommia ulmoides. There were high colonization rates (4..9%―63.1%) and isolation rates (0.7―0.93) of endophytic fungi, and they were conspicuously higher in twigs than those in leaves in the 6 plants examined. The colonization and isolation rates of endophytic fungi increased with the twig age. The results based on the analyses of cluster and Sorenson's similarity coefficients indicated that some endophytic fungi showed a certain degree of host and tissue preference.

关键词： endophytic fungus medicinal plant diversity host and tissue preference

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Experimental Study of Sediment Incipience Under Complex Flows

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Transactions of Tianjin university 2008年第4期14卷 300-306页

作者： LIU Chunrong DENG Liying HUANG Zhenhua HUHE Aode Maritime Research Center School of Civil and Environmental Engineering Nanyang Technological University Singapore 639798 College of Mechanics and Aerospace Hunan University Changsha 410082 China school of Civil and Environmental Engineering Nanyang Technological University Singapore 639798 Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Sediment incipience under flows passing a backward-facing step was studied. A series of experiments were conducted to measure scouring depth, probability of sediment incipience, and instantaneous flow velocity field downstream of a backward-facing step. Instantaneous flow velocity fields were measured by using Particle Image Velocimetry (PIV), and an image processing method for determining probability of sediment incipience was employed to analyze the experimental data. The experimental results showed that the probability of sediment incipience was the highest near the reattachment point, even though the near-wall instantaneous flow velocity and the Reynolds stress were both much higher further downstream of the backward-facing step. The possible me- chanisms are discussed for the sediment incipience near the reattachment point.

关键词： sediment transport local scour complex flows particle image velocimetry sediment incipience

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The crustal structure under Sanjiang and its dynamic implications:Revealed by seismic reflection/refraction profile between Zhefang and Binchuan,Yunnan

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Science China Earth sciences 2005年第9期48卷 1329-1336页

作者： ZHANG Zhongjie1, BAI Zhiming1, WANG Chunyong2, TENG Jiwen1, Lü Qingtian3, LI Jiliang1, LIU Yifeng1 & LIU Zhenkuan4.1. Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, China 2. Institute of Geophysics, China Seismological Bureau, Beijing 100085, China 3. Institute of Deposition Resource, Chinese Academy of Geosciences, Beijing 100037, China 4. school of Exploration and Information, China university of Geosciences, Beijing 100083, China 1. Institute of Geology and Geophysics Chinese Academy of Sciences 100029 Beijing China 2. Institute of Geophysics China Seismological Bureau 100085 Beijing China 3. Institute of Deposition Resource Chinese Academy of Geosciences 100037 Beijing China 4. school of Exploration and Information China University of Geosciences 100083 Beijing China

The fault belts in Sanjiang mainly include Jinshajiang-Honghe fault, Lancangjiang fault and Nujiang fault (called Sanjiang faults) in western Yunnan Province, China. By interpreting the wide-angle seismic reflection/refraction profile between Zhefang and Binchuan, which crosses Tengchong and Baoshan blocks in Dianxi (western Yunnan) tectonic zone, we recon- struct the crustal structure with seismic traveltime tomography for crustal P-wave velocity and the seismic scattering image for crustal seismic reflection structure. In this paper, we firstly present the crustal structure images of P-wave velocity and seismic reflection under the wide-angle seismic profile. These results demonstrate that, the crustal velocity structure and seismic reflec- tion structure along the profile can be divided into 3 segments, and there is an obvious difference of crustal structure among the eastern, the western and the middle segment. Generally, crustal P-wave velocities in the Baoshan segment are 0.1―0.2 km/s slower and seismic reflection am- plitudes from Moho discontinuity are stronger than the other 2 segments. In the studied area, crustal thickness is about 4. km, and shows the thickening tendency from west to east along the profile. Additionally, it can be seen that there is one strong-amplitude seismic reflection event as bright points at the depths of 8―10 km, along the segment of 80―115 km of the profile (south- ward of Tengchong); and seismic reflection wave-field from Moho discontinuity varies obviously along the lateral direction. Finally, we make some discussions on the crustal thickening pattern in the Sanjiang fault belt, structural environment of earthquake development and the contact rela- tionship between the Tengchong block, Banshan block and Luxi trough.

关键词： Sanjiang area wide-angle seismic profile crustal structure.

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Evaluation on Methods of Estimating Winter Habitat Carrying Capacity of Cervidae

Evaluation on Methods of Estimating Winter Habitat Carrying ...

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第二届全国野生动物生态与资源保护学术讨论会

作者： Zhang minghai Liu qunxiu (school of wildlife,Northeast forestry university,Har’rbin 15004.)

Two primary methods were summarized to estimate habitat carrying capacity,by nutrition and by space,according to the current research status of deer carrying capacity in recent years;also evaluation and comparison wer...

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Regioselective aminohalogenation of β-nitrostyrenes using NCS and NBS as nitrogen/halogen sources

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Science China Chemistry 2010年第1期53卷 140-146页

作者： ZHI SanJun1,2,SUN Hao2,LIN Chen2,ZHANG GuangQian2,LI GuiGen4.& PAN Yi2,3 1 Department of Chemistry,Huaiyin Normal university,Huai’an 221003,China 2 school of Chemistry and Chemical Engineering,Nanjing university,Nanjing 210093,China 3 State Key Lab of Coordination Chemistry,Nanjing university,Nanjing 210093,China 4.Department of Chemistry and Biochemistry,Texas Tech university,Lubbock,Texas 794.9-1061,usa 1. Department of Chemistry Huaiyin Normal University Huai’an 221003 China2. School of Chemistry and Chemical Engineering Nanjing University Nanjing 210093 China4. Department of Chemistry and Biochemistry Texas Tech University Lubbock Texas 79409-1061 USA3. State Key Lab of Coordination Chemistry Nanjing University Nanjing 210093 China

Aminohalogenation reaction of β-nitrostyrenes with N-halosuccinimides(N-chloro and N-bromosuccinimides) has been successfully conducted by using nickel acetate as a catalyst in the presence of potassium carbonate and succinimide as *** reaction was easily performed at room temperature under nitrogen gas protection to give dihalorinaed haloamino products in good to excellent yields(60%-98%).The structure has been confirmed by X-ray crystal structure analysis.

关键词： aminohalogenation vicinal haloamines β-nitrostyrenes NBS NCS

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Growth characteristics and response to climate change of Larix Miller tree-ring in China

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Science China Earth sciences 2010年第6期53卷 871-879页

作者： SUN Yu1,4. WANG LiLi1,2,3, CHEN Jin5, DUAN JianPing1,4. SHAO XueMei1,2 & CHEN KeLong6 1 Institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, China 2 Institute of Tibetan Plateau Research, Chinese Academy of sciences, Beijing 100085, China 3 Institute of Desert and Meteorology, China Meteorological Administration, Urumqi 830002, China 4.Graduate university of Chinese Academy of sciences, Beijing 10004., China 5 Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of sciences, Beijing 10004., China 6 school of Life and Geography sciences, Qinghai Normal university, Xining 810008, China 1. Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China4. Graduate University of Chinese Academy of Sciences Beijing 100049 China2. Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China3. Institute of Desert and Meteorology China Meteorological Administration Urumqi 830002 China5. Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Beijing 100044 China6. School of Life and Geography Sciences Qinghai Normal University Xining 810008 China

As one of the earliest species used in dendrochronological studies, Larix responds sensitively to climate change. In this study, nine larch species and one variety from eleven sites were collected to study the growth characteristics of tree-ring width using dendrochronological methods. Ten residual tree-ring chronologies were developed to analyze their relationships with regional standardized anomaly series by Pearson’s correlation analysis. The results suggest that most of the chronologies had significantly positive correlations with the mean temperature and mean maximum temperature in May. The spring temperature evidently limited the radial growth of the larch species without precipitation control. The largest mean tree-ring width was found in Himalayan Larch in Jilong, whereas Master Larch in Si’er reflected the smallest mean value. Both species presented little climate information in this study. Chinese, Potanin, and Tibetan larches are significantly correlated with climate change, implying a huge potential for climate history reconstruction. The elevation of the sampling sites appears to be an important condition for tree-ring growth of larches responding to climate factors.

关键词： Larix Miller tree-ring climate change mean temperature in May

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QUANTITATIVE ANalYSIS OF RELATIONSHIP BETWEEN ARMILLARIA ROOT ROT AND SITE FACTORS IN PINUS RADIATA PLANTATIONS

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生物数学学报 1995年第3期10卷 9-14页

作者： Shu Qinglong He Min Song Shumei Zhao Weizhong(Department of forestry,Anhui Agricultural university,Hefei 230036)(school of forestry,university of Canterbury,Christchurch,New Zealand)(Shanxi Agricultura1 university,Taigu,shanxi.)

Incidence of Armillaria infection was quantified based on site factors in New Zealand Pinus radiata plantations.A linear multiple regression model was derived to predict infection levels of Armillaria root *** positivily associated with the infection were:previous vegetation（native bush,pine）;soil type（pumice）;landform （valley,gully,flat）and the interaction between *** model could assist in management planning with regard to the predisposition of particular stand to Armillaria ***:Armillaria root rot,Disease incidence,Site factors,Quantification,Pinus radiata.

关键词： SITE ROOT root QUANTITATIVE ANalYSIS OF RELATIONSHIP BETWEEN ARMILLARIA ROOT ROT AND SITE FACTORS IN PINUS RADIATA PLANTATIONS

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Influence of expressed TRAIL on biophysical properties of the human leukemic cell line Jurkat

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Cell Research 2004年第2期14卷 161-168页

作者： Kai CHEN~(1,*), Dan LI~(1,*), Yu Hui JIANG~1, Wei Juan YAO~1, Xin Juan WANG~2, Xiao Chao WEI~2, Jing GAO~3, Li De XIE~1, Zong Yi YAN~4. Zong Yao WEN~(1**), Shu CHIEN~5 ~1Hemorheology Center, Department of Biophysics, school of Basic Medical sciences, Peking university, Beijing, 100083, China. ~2Department of Biochemical and Molecular Biology, school of Basic Medical sciences, Peking university, Beijing, 100083, China. ~3Department of Urology, Medical Center, New York university, usa. ~4.epartment of Mechanics and Engineering Science, Peking university, Beijing 100871, China. ~5Department of Bioengineering and Whitaker Institute of Biomedical Engineering, university of California, San Diego, La Jolla, CA 92093-04.2, usa 1Hemorheology Center Department of Biophysics School of Basic Medical Sciences Peking University Beijing 100083 China. 1Hemorheology Center Department of Biophysics School of Basic Medical Sciences Peking University Beijing 100083 China. 1Hemorheology Center Department of Biophysics School of Basic Medical Sciences Peking University Beijing 100083 China. 1Hemorheology Center Department of Biophysics School of Basic Medical Sciences Peking University Beijing 100083 China. 2Department of Biochemical and Molecular Biology School of Basic Medical Sciences Peking University Beijing 100083 China. 2Department of Biochemical and Molecular Biology School of Basic Medical Sciences Peking University Beijing 100083 China. 3Department of Urology Medical Center New York University USA. 1Hemorheology Center Department of Biophysics School of Basic Medical Sciences Peking University Beijing 100083 China. 4.epartment of Mechanics and Engineering Science Peking University Beijing 100871 China. 1Hemorheology Center Department of Biophysics School of Basic Medical Sciences Peking University Beijing 100083 China. 5Department of Bioengineering and Whitaker Institute of Biomedical Engineering University of California San Diego La Jolla CA 92093-0412 USA

The cDNA fragment of human TRAIL (TNF-related apoptosis inducing ligand) was cloned into RevTet-On, a Tetregulated and high-level gene expression system. The gene expression system was constructed in a human leukemic cell line: Jurkat. By using RevTet-On TRAIL gene expression system in Jurkat as a cell model, we studied the influence of TRAIL gene on the changes of cellular apoptosis before and after the TRAIL gene expression, which was induced by adding tetracycline derivative doxycycline (Dox). The results indicated that the cellular apoptosis ratio was largely dependent on the TRAIL gene expression level. Moreover, it was found that the apoptosis-inducing TRAIL could cause significant changes in the biophysical properties of Jurkat cells. The cell surface charge density decreased, the membrane fluidity declined, the elastic coefficients K_I increased, and the proportion of α-helix in membrane protein secondary structure decreased. Thus, the apoptosis-inducing TRAIL gene caused significant changes on

关键词： TRAIL Tet gene expression system Jurkat apoptosis.

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Advanced information feedback strategy in intelligent two-route traffic flow systems

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Science China(Information sciences) 2010年第11期53卷 2265-2271页

作者： DONG ChuanFei1,2, MA Xu1,3 & WANG BingHong1,4.1Department of Modern Physics and Nonlinear Science Center, university of Science and Technology of China (USTC), Hefei 230026, China 2school of Earth and Atmospheric sciences, Georgia Institute of Technology, Atlanta, GA 30332, usa 3 Department of Physics, Syracuse university, Syracuse, NY 1324., usa 4.he Research Center for Complex System Science, university of Shanghai for Science and Technology and Shanghai Academy of System Science, Shanghai 200093, China 1. Department of Modern Physics and Nonlinear Science Center University of Science and Technology of China (USTC) Hefei 230026 China2. School of Earth and Atmospheric Sciences Georgia Institute of Technology Atlanta GA 30332 USA3. Department of Physics Syracuse University Syracuse NY 13244 USA4. The Research Center for Complex System Science University of Shanghai for Science and Technology and Shanghai Academy of System Science Shanghai 200093 China

The optimal information feedback has a significant effect on many socioeconomic systems like stock market and traffic systems aiming to make full use of resources. In this paper, we study dynamics of traffic flow with real-time information. The influence of a feedback strategy named vehicle number feedback strategy (VNFS) is introduced, in which we only calculate the vehicle number of first 500 route sites from the entrance. Moreover, the two-route traffic system has only one entrance and one exit, which is different from those in the previous work. Our model incorporates the effects of adaptability into the cellular automaton models of traffic flow, and simulation results by adopting this optimal information feedback strategy have demonstrated higher efficiency in controlling spatial distribution of traffic patterns than the other three information feedback strategies, i.e., TTFS, MVFS and CCFS.

关键词： vehicle number feedback strategy two-route selecting traffic flow intelligent vehicle cellular automaton model

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