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| 1 | Magnetostratigraphy of the late Cenozoic Laojunmiao anticline in the northern Qilian Mountains and its implications for the northern Tibetan Plateau uplift显示文摘Cenozoic sediments in the foreland basin--Jiuquan Basin in west Hexi Corridor recorded tectonic uplift information of the Qilian Mountains. High resolution paleomagnetic dating of the Laojunmiao (LJM) section across the central LJM anticline in the southern Jiuquan Basin reveals ages of the Getanggou Member, Niugetao Member in the Shulehe Formation, the Yumen Conglomerate, Jiuquan Conglomerate and Gobi Formation at >13-8.3 Ma, 8.3-4.9 Ma, 3.66-0.93 Ma, 0.84-0.14 Ma and 0.14-0 Ma, respectively. Sedimentary evolution study suggests that the Qilian Mountains should begin to rise gradually since ~8-6.6 Ma, accompanied by sedimentary environments changing from lacustrine mudstones-sandstones to alluvial conglomerates. Rapid uplift of the Qilian Mountains began at ~3.66 Ma, followed by a series of stepwise or intermittent intensive uplifts at about <1.8-1.23 Ma, 0.93-0.84 Ma and 0.14 Ma, which finally resulted in the present high Qilian Mountains. | FANG Xiaomin1,2, ZHAO Zhijun3,2, LI Jijun2, YAN Maodu2, PAN Baotian2, SONG Chunhui2 & DAI Shuang2 1. Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, China 2. Key Laboratory of Western China’s Environmental Systems, Ministry of Education & College of Resources and Environment, Lanzhou University, Lanzhou 730000, China 3. College of Geography, Nanjing Normal University, Nanjing 210097, China | 2005 | Science China Earth Sciences2005，48，7： | 61 |
| 2 | The effect of folic acid on the development of stomach and other gastrointestinal cancers显示文摘Objective To evaluate the roles of folic acid and β-carotene in the chemoprevention of gastric and other gastrointestinal (GI) cancers. Methods In a randomized, double-blind, placebo-controlled trial, a total of 216 patients with atrophic gastritis were randomly assigned to one of the four groups: ①folate (FA, 20 mg per day plus vitamin B 12 1 mg, intramuscularly, per month for one year, then 20 mg two times a week plus 1 mg per three months for the next year); ②natural β-carotene (N-βC, 30 mg per day for first year, then 30mg two times a week for the next); ③synthetic β-carotene (S-βC, administered as in N-βC); and ④placebo. Follow-ups continued from 1994 to 2001. Results A total of 7 new cases of gastrointestinal cancers were diagnosed with 3 stomach, 1 colon and 1 esophageal cancers occurring in the placebo group; 1 stomach cancer in both of the N-βC and S-βC groups, and no cancer occurring in FA group. In terms of GI cancers, there was a significant reduction in the FA group, compared with the placebo group (P= 0.04). A similar trend was observed in both N-βC and S-βC groups (P=0.07-0.08). Taken together, the three intervention groups displayed a highly significant decrease in occurrence (P=0.004, vs placebo), and a lower risk for GI cancers (OR=0.12; 95% confidence interval, 0.03-0.51). For development of gastric cancer, any one of the three active-treated groups did not reach statistically significant reduction. The FA group showed obvious improvement of the gastric mucosal lesions with more patients displaying lesions reversed or stable atrophy and inflammation (P=0.04), reversed intestinal metaplasia (P=0.06) at the end of follow-up, and reversed displasia (P=0.017) at 12 months. Two cases of false jaundice were found in β-carotene groups with no influence on administration, and no side-effects were reported in FA group. Conclusions This trial revealed the interventional effect of folic acid on the development of GI cancers, a similar effect of β-carotene was also detected. Also, folic acid may be of use to treat atrophic gastritis by preventing or reversing the precancerous lesions. | 朱舜时 施尧 胡运彪 李蓉蓉 汪敏 周怡和 金冠球 谢宇野Shanghai Navy Hospital Shanghai 200081 China 邬桂泉 夏德凰Shanghai Putuo People's Hospital 钱珍华 宋海连Shanghai Traditional and Western Medical Integrated Hospital 屠伯强 张丽冬 萧树东 | 2003 | Chinese Medical Journal2003，，1： | 42 |
| 3 | The vegetation and climate change during Neocene and Early Quaternary in Jiuxi Basin, China显示文摘Sporopollen record in the Laojunmiao Section at Yumen in the Hexi Corridor foreland depression at the northern margin of the Tibetan Plateau revealed that during the period of 13.0―11.15 Ma the ecological environment of the Jiuxi Basin is characterized by steppe vegetation and a semi-moist climate. During 11.16―8.60 Ma prevailed forests of cypress and a still warmer, moister climate; steppe vegetation and dry climate began probably at about 8.6 Ma. Although aridification had been relaxed time and again during 8.40―6.93 Ma (forest-steppe, warm-semi-moist), 6.64―5.67 Ma (open-forest and steppe, warmer-semi-moist) and 5.42―4.96 Ma (steppe, semi-arid), the climate in the region became drier and drier in response to the fre- quent occurrence of aridity during 6.93―6.64 Ma (steppe, semi-arid), 5.67―5.42 Ma (de- sert-steppe, arid), 3.66―3.30 Ma (desert-steppe, arid) and 2.56―2.21 Ma (desert, arid). Perhaps the important findings of our study are the notable expansion of drought-enduring plants during 3.66―3.30 Ma and about 2.56 Ma and the replacement of vegetation by vast arid desert. | MA Yuzhen 1 , FANG Xiaomin 1,2 , LI Jijun 1 , WU Fuli 1 & ZHANG Jun 1 1. Key Laboratory of Western China’s Environmental Systems and College of Resources and Environment, Lanzhou University, Lanzhou 730000, China 2. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China | 2005 | Science China Earth Sciences2005，48，5： | 31 |
| 4 | Modelling of multi-bodies in close proximity under water waves——Fluid resonance in narrow gaps显示文摘Viscous fluid model and potential flow model with and without artificial damping force(f=-μV,μ the damping coefficient and V the local averaging flow velocity) are employed in this work to investigate the phenomenon of fluid resonance in narrow gaps between multi-bodies in close proximity under water waves.The numerical results are compared with experimental data available in the literature.The comparison demonstrates that both the viscous fluid model and the potential flow model are able to predict the resonant frequency reasonably well.However the conventional potential flow model(without artificial damping term) significantly over-predicts the wave height in narrow gaps around the resonant frequency.In order to calibrate the appropriate damping coefficient used for the potential model and make it work as well as the viscous fluid model in predicting the resonant wave height in narrow gaps but with little computational efforts,the dependence of damping coefficient μ on the body geometric dimensions is examined considering the parameters of gap width Bg,body draft D,body breadth ratio Br and body number n(n = 2,3),where Br = BB/BA for the case of two bodies(Body A and Body B) with different breadths of BA and BB,respectively.It was confirmed that the damping coefficient used for the potential flow model is not sensitive to the geometric dimensions and spatial arrangement.It was found that μ∈ [0.4,0.5] may guarantee the variation of Hg/H0 with kh to be generally in good agreement with the experimental data and the results of viscous fluid model,where Hg is the excited wave height in narrow gaps under various dimensionless incident wave frequencies kh,H0 is the incident wave height,k = 2π/L is the wave number and h is the water depth. | LU Lin1,2,TENG Bin3,CHENG Liang 4,SUN Liang5 & CHEN XiaoBo6 1 Center for Deepwater Engineering,Dalian University of Technology,Dalian 116024,China 2 State Key Laboratory of Structural Analysis for Industrial Equipment,Dalian University of Technology,Dalian 116024,China 3 State Key Laboratory of Coastal and Offshore Engineering,Dalian University of Technology,Dalian 116024,China 4 School of Civil and Resource Engineering,The University of Western Australia,Crawly 6003,Australia 5 Centre for Offshore Research and Engineering,Department of Civil Engineering,National University of Singapore,117576,Singapore 6 Research Department,Bureau Veritas,Neuilly-Sur-Seine,92570,France | 2011 | Science China(Physics,Mechanics & Astronomy)2011，54，1： | 29 |
| 5 | Geomorphologic evolution and environmental changes in the Shaluli Mountain region during the Quaternary显示文摘Geologic and geomorphologic evidence from the Shaluli Mountain indicates that the planation surface that formed in the Late Tertiary disintegrated during the Late Pliocene-Early Quaternary. At the same time, rift ba- sins appeared on some parts of the planation surface, and began to accumulate fluvial-lacustrine sediment. These are interpreted as being the response of this region to Phase-A of the Qingzang Tectonic Movement. After this, the Shaluli Mountain continued to rise in several pulses. Faulting and incision by some large tributaries of the Jinsha and Yalong Rivers resulted in several rift river valleys and the earliest terraces. Generally, the planation surface in this region had been uplifted to about 3500—3700 m a.s.l. no later than 550—600 ka BP, after the Kunlun-Huanghe Tectonic Move- ment, and coupled with global glacial climate, and resulted in the earliest glaciation recognized so far in the Hengduan Mountains. At the same time, loess was deposited in the Ganzi area of the northern Shaluli Mountain. During the last glacial period, the Shaluli Mountain approached its present altitude and developed several large ice caps, such as the Daocheng Ice Cap and Xinlong Ice Cap, as well as several huge valley glaciers. These paleoglaciers produced some of the most spectacular glacial topography on the Tibetan Pla- teau. | ZHOU Shangzhe1,2, XU Liubing1, CUI Jianxin1, ZHANG Xiaowei1 & ZHAO Jingdong1 1. National Laboratory of Western China’s Environmental Systems of Ministry of Education of China and Department of Geography, Lan- zhou University, Lanzhou 730000, China 2. Department of Geography, South China Normal University, Guang- zhou 510631, China | 2005 | Chinese Science Bulletin2005，50，1： | 25 |
| 6 | A 60-year journey of mycorrhizal research in China:Past,present and future directions显示文摘The significance of mycorrhizas(fungal roots in 90% of land plants) in plant nutrient acquisition and growth,element biogeo-chemical cycling and maintaining of terrestrial ecosystem structures has been globally established for more than 120 years.Great progress in mycorrhizal research in the past 60 years(1950-2009,1981-2009 in particular) has also been made across China,particularly in the mainland,Hong Kong and Taiwan.For instance,a total of 20 new and ~120 records of arbuscular mycorrhizal(AM) fungal species,30 new and ~800 records of ectomycorrhizal(EM) fungal species,a dozen of new and ~100 records of orchid mycorrhizal(OM) fungal species have been isolated by morphological observation and/or molecular identification in China since the 1950s.Great accomplishment has also been made in the following area,including fungal species richness and genetic structure,relationships between species composition and plant taxa,effects of mycorrhizal fungi on plant nutrient uptake and growth,resistances to pathogens and interactions with other soil microorganisms,potential of mycorrhizal fungi in phytoremediation and/or land reclamation,alterations of enzymatic activities in mycorrhizal plants,and elevated CO2 and O3 on root colonization and species diversity.Unfortunately,the international community cannot easily appreciate almost all Chinese mycorrhizal studies since the vast majority of them have been published in Chinese and/or in China-based journals.The aim of this review is to make a comprehensive exposure of the past and present China's major mycorrhizal research to the whole world,and then to suggest potential directions for the enhancement of future mycorrhizal research within and/or between the Chinese and international mycorrhizal community. | HE XinHua1,2,3*,DUAN YingHua2,CHEN YingLong4 & XU MingGang2 1School of Life Sciences,Yunnan Normal University,Kunming 650092,China 2Key Laboratory of Crop Nutrition and Fertilization,Ministry of Agriculture of China,Institute of Agricultural Resources and Regional Planning,Chinese Academy of Agricultural Sciences,Beijing 100081,China 3Centre for Ecosystem Management,School of Natural Resources,Edith Cowan University,Joondalup,WA 6027 State Centre of Excellence for Ecohydrology,School of Plant Biology,University of Western Australia,Crawley,WA 6009,Australia 4School of Earth and Environment,University of Western Australia,Crawley,WA 6009,Australia | 2010 | Science China(Life Sciences)2010，53，12： | 23 |
| 7 | Hypertension and renal disease显示文摘The relationship between chronic kidney disease(CKD)and hypertension remains enigmatic and a matter of considerable clinical and academic interest with evidence indicating that hypertension is both a cause and a consequence of kidney disease[1-2]. | Huang Chunfa Louis Stokes Cleveland Veteran Affairs Medical Center Division of Nephrology,Departments of Medicine,Case Western Reserve University and Rammelkamp Center for Research and Education,MetroHealth System Campus,Cleveland,Ohio 441061 | 2011 | 中华高血压杂志2011，19，12： | 23 |
| 8 | Using lightning locating system based on time-of-arrival technique to study three-dimensional lightning discharge processes显示文摘A time-of-arrival(TOA) system based on GPS technology for locating VHF radiation sources from lightning has been developed and used in observation sites in the northern Shandong Province,China.The 3D images of the lightning progression have been obtained successfully for the first time in China.The 3D-channel evolutions of typical negative CG,positive CG and IC lightning flashes have been discussed together with the data of fast electric field change.It was found that significant differences existed between the negative and positive CG lightning flashes in terms of the initiation and propagation of the radiation sources.The preliminary breakdown of a negative CG lightning flash propagated at a speed about 5.2×104 m/s.The stepped leader of negative CG lightning flashes was trigged by negative initial breakdown.Thereafter,it propagated downward at a speed of 1.3×105 m/s.The initial process of the positive CG lightning flashes was also a propagation process of negative streamer.These streamers propagated dominantly horizontally in the positive charge region and accumulated positive charges at the origin of the lightning,and as a consequence,initiated downward positive streamers.A new type of lightning discharge that was triggered by a narrow bipolar pulse(NBP) is discussed in this study.The NBP was originated at altitude of about 10.5 km in the upper positive charge region.As a distinct difference from normal IC flash,its channels extended horizontally all around and produced a lot of radiation sources.The source power of the NBP could approach 16.7 kW,which is much greater than that of normal lightning discharge ranging between 100 mW and 500 W.The 3D propagation of this new type of lightning discharge was observed and obtained for the first time in China.The possible initiation mechanism of this new type of light-ning is discussed here. | ZHANG GuangShu1,WANG YanHui1,QIE XiuShu2,ZHANG Tong1,ZHAO YuXiang1,3,LI YaJun1 & CAO DongJie11 Laboratory for Climate Environment and Disasters of Western China,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 730000,China 2 Laboratory for Middle Atmosphere and Global Environment Observation(LAGEO),Institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing 100029,China 3 Department of Physics,Tianshui Normal College,Tianshui 741001,China | 2010 | Science China Earth Sciences2010，53，4： | 21 |
| 9 | Palaeogene fossil Populus leaves from Lanzhou Basin and their palaeoclimatic significance显示文摘An angiosperm compression flora is found in Palaeogene from Lanzhou Basin and the cuticular analysis of Populus davidiana Dode in the flora is carefully made. Fur-thermore, the fossil cuticles are compared with the epidermal structures of extant Populus leaves growing in different en-vironments, i.e. moist, semimoist, and semiarid to arid cli-matic regions. The present experiments indicate that mature leaves of P. davidiana show leaf size from big to small, leaf cuticles from thick to thin and anticlinal walls of epidermal cells from faintness to clarity along with the increase of lati-tudes of the plant distributions, the climatic variation from moist to arid, the annual precipitation from more to less and the annual mean temperature from high to low. The fossil P. davidiana differs from the specimens collected from Shandan in semiarid to arid climatic regions but closely resembles the Wushan leaves in a semi-moist climatic area in a lot of fea-tures. In a word, the new research may reflect that the flora lives in a semi-moist climatic environment. The present dis-covery of compression of Paleogene Populus davidiana is of great significance to studying vegetation types, climatic and environmental changes during the primal uplifting of the Qinghai-Tibet Plateau. | SUN Bainian1,2, YAN Defei1, XIE Sanping1, CONG Peiyun1, XIN Cunlin1 & YUN Fei1 1. Key Laboratory of Western China抯 Environmental Systems of the Ministry of Education, Lanzhou University, Lanzhou 730000, China 2. State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sci-ences, Nanjing 210008, China | 2004 | Chinese Science Bulletin2004，49，14： | 20 |
| 10 | Multislice CT angiography in coronary artery disease: Technical developments, radiation dose and diagnostic value显示文摘Multislice computed tomography (CT) angiography has been increasingly used in the detection and diagnosis of coronary artery disease because of its rapid technical evolution from the early generation of 4-slice CT scanners to the latest models such as 64-slice, 256-slice and 320-slice CT scanners. Technical developments of multislice CT imaging enable improved diagnostic value in the detection of coronary artery disease, and this indicates that multislice CT can be used as a reliable lessinvasive alternative to invasive coronary angiography in selected patients. In addition, multislice CT angiography has played a significant role in the prediction of disease progression and cardiac events. Despite promising results reported in the literature, multislice CT has the disadvantage of having a high radiation dose which could contribute to the radiation-induced malignancy. A variety of strategies have been currently undertaken to reduce the radiation dose associated with multislice CT coronary angiography while in the meantime acquiring diagnostic images. In this article, the author will review the technical developments, radiation dose associated with multislice CT coronary angiography, and strategies to reduce radiation dose. The diagnostic and prognostic value of multislice CT angiography in coronary artery disease is briefly discussed, and future directions of multislice CT angiography in the diagnosis of coronary artery disease will also be highlighted. | Zhonghua Sun, Discipline of Medical Imaging, Department of Imaging and Applied Physics, Curtin University of Technology, Perth, Western Australia 6845, Australia | 2010 | World Journal of Cardiology2010，2，10： | 19 |
| 11 | Effect of arsenic trioxide on rat hepatocarcinoma and its renal cytotoxicity显示文摘AIM: To study the effect of arsenic trioxide (As2O3) on rat experimental hepatocarcinoma and its renal cytotoxicity.METHODS: The hepatocarcinoma model was established by diethaylnitrosamine perfusion in stomach of 120 Wistar rats, and the treatment began at the end of 20 weeks.Before the treatment, the rat models were randomly divided into 5 groups. In the treatment groups, three doses of As2O3 were injected into rat abdominal cavity, the total time of drug administration was 4 weeks. Cisplatin control or the blank group was injected into abdominal cavity with equal amount of cisplatin or saline at the same time,respectively. On the 7th, 14th and 28th day after the treatment, the hepatocarcinoma nodules were obtained and the morphologic changes of hepatocarcinoma cells were observed under light and electron microscopes;Immunohistochemistry (S-P methods) was employed to detect the expression of bcl-2, bax and PCNA in hepatocarcinoma tissues; flow cytometry (TUNEL assay)was used to detect the apoptosis of liver cancer cells and the change of cytokinetics. On the 28th day, the kidneys were obtained and their histologic changes were observed under light microscope, and immunohistochemistry (SP stain) was also employed to detect the expression of bcl-2and PCNA. Cisplatin and saline solution were used as the control.RESULTS: As2O3 could induce the apoptosis of rat liver cancer cells and exhibited typical morphologic changes.The incidence of apoptosis of hapatocarcinoma cells was elevated (P=0.001). The elevation was the most higher in the group of middle-dose of As2O3 (1 mg.kg-1), significantly higher than that of the other arsenic groups and the controls (P=0.001). Large dose of As2O3 (5 mg.kg-1) was able to arise the incidence of apoptosis, but also produced a large amount of necrosis and inflammatory reaction. Middle dose of As2O3 dramatically increased the cell number in G2/M phase (P=0.0001), and apoptosis happened apparently.The expression of bcl-2 and bax was related to the dose of As2O3. With the up-regulation of apoptotic incidence, the ratio of bcl-2/bak decreased. But the incidence of apoptosis was not the highest status and the ratio of bcl-2/bax was at the lowest when the highest-dose of As2O3 was used.There was significant difference among the PCNA indexes (PCNA L1) of the five groups. Of them, three arsenic groups all showed decrease of different degrees, and this downregulation was most obvious in group A. There was significant difference among the three groups (P=0.016).Under the light microscope, the rat kidney in the cisplatin group exhibited tubular epithelium swelling and degeneration, protein casts in collecting tubules; While all arsenic groups didn't show the significant changes (P=0.013).In the arsenic groups, the expression of bcl-2 in the renal tubular epithelium was increased (P=0.005), no obvious changes happened to PCNA L1. But in the group of cisplatin,the PCNA L1 increased significantly (P=0.001).CONCLUSION: AS2O3 can induce apoptosis of rat hepatocellular carcinoma cells. And there is optimum dose;too high dose will induce the cytotoxic effect, while certain dose of As2O3 is able to block the cell cycle at G2/M phase.As2O3 had the most remarkable influence on G2/M cells,and it can also induce apoptosis to cells at other phases.As2O3 can restrain the proliferation of rat hepatocellular carcinoma cells, in a dose-time dependent manner.Compared with cisplatin, As2O3 didn't show obvious renal toxicity, which was related to the increasing expression of bcl-2 in renal tubular epithelium, the inhibition of apoptosis and the anti-oxidation effects. | Shao-Shan Wang Ti Zhang Xi-Lu Wang Li Hong Department of Surgery of Dagang Hospital 300270,Tianjin,China Qing-Hui Qi Department of Chinese and Western Integral Surgery of Master Hospital of Tianjin Medical University 300052,Tianjin,China | 2003 | World Journal of Gastroenterology2003，9，5： | 17 |
| 12 | Rb1 protects endothelial cells from hydrogen peroxide-induced cell senescence by modulating redox status显示文摘Objectives Endothelial senescence has been proposed to be involved in endothelial dysfunction and atherogenesis. This study investigates the effects of ginsenoside Rbl, a major constituent of ginseng,on H2O2-induced endothelial senescence.Methods Primary human umbilical vein endothelial cells(HUVECs) senescence was induced by H2O2 as judged by senescence-associated P-galactosidase assay (SA-P-gal).Fntracellur superoxide dismutase(S0D1) activity and malondialdehyde(MDA) level were determined by commercial kit.S0D1 mRNA and protein expression were analyzed by real time PCR and Western blot.Reactive oxygen species(ROS) were determined by flow cytometry.Results Rb1 was found to reverse endothelial senescence,as witnessed by a significant decrease of senescent cell numbers. Rbl could markedly increase intracellular SOD activity, decrease the MDA level,and suppress the generation of intracellular ROS in H2O2-treated HUVECs.Consistent with these findings,Rbl can effectively restore SOD1 mRNA and protein expression which decreased in H2O2 treated cells. Conclusions Our report demonstrates thatRbl can exert reversal effects on H2O2-induced cellular senescence through modulating cellular redox status. | LIU Ding-hui~1,CHEN Yan-ming~2,LIU Yong~1,HAO Bao-shun~1, ZHOU Bin~1,WU Lin~1,WANG Min~1,CHEN Lin~1,WU Wei-kang~3,QIAN Xiao-xian~1 (1.Department of Cardiology,The Third Affiliated Hospital of Sun Yat-sen University,Guagnzhou 510630 2.Department of Endocrinology,The Third Affiliated Hospital of Sun Yat-sen, Guagnzhou 510630 3.Institute Integrated Traditional Chinese and Western Medicine,Sun Yat-sen University,Guagnzhou 510630) | 2011 | 岭南心血管病杂志2011，17，S1： | 15 |
| 13 | 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 |
| 14 | Inhibition of Celastrus orbiculatus Extracts on VEGF Expression in Hepatoma Cells of Mice显示文摘Objective To discuss the antitumor mechanism preliminarily by observing effects of Celastrus orbiculatus extracts(COE) on vascular endothelial growth factor(VEGF) mRNA and protein expression in hepatoma(Hepa1-6) cells of mice.Methods Hepa1-6 cells were treated with COE at different nontoxic concentration(0,10,20,40,80,and 160 μg/mL) for 16 h.The mRNA and protein expressions of VEGF were detected by reverse transcription-PCR and Western Blotting,respectively.Results COE significantly inhibited VEGF expression at both mRNA and protein levels in a dose-dependent manner.Conclusion COE can inhibit VEGF expression in Hepa1-6 cells,therefore suggest that VEGF could be chosen as an therapeutic target for COE in the context of cancer chemoprevention and anticancer therapy. | QIAN Ya-yun,LIU Yan-qing Institute of Traditional Chinese Medicine & Western Medicine,Yangzhou University,Yangzhou 225009,China | 2010 | Chinese Herbal Medicines2010，2，1： | 11 |
| 15 | Preliminary study on interaction between plant frictional root and rock-soil mass显示文摘The interaction between lateral root system of woody plant and soil mass is similar to the one between shrub, herbage and soil mass, and has the effect of frictional reinforcement on slope soil. It plays an important role in reinforcing soil strength in shallow slope. Therefore, slope soil mass can be considered as a composite of soil and plant roots and the soil strength and stability of shallow slope soil mass are improved. However, current researches still remain on the level of qualitatively analyzing the relation between root and soil mass. In this paper, some exploratory researches on quantitative analysis of the interaction mechanism between root and soil mass are conducted. With the study of interaction between herbage root system (lateral root system of woody plants) and soil mass, the mechanical model of interaction between frictional root and soil mass is established. The accuracy of the model is verified by field experiments of Pinus Yunnanensis. The mechanical model provides a crucial theoretical guidance to quantitatively analyzing the interaction between plant root and soil mass; it also has certain values in application. | YAN ZhiXin1’2, SONG Yun3, JIANG Ping1’2 & WANG HouYu4 1 Key Laboratory of Mechanics on Disaster and Environment in Western China (Lanzhou University), Ministry of Education, Lanzhou 730000, China 2 School of Civil Engineering and Mechanics, Lanzhou University, Lanzhou 730000, China 3 College of Civil Engineering and Mechanics, Central South University of Forestry and Technology, Changsha 410004, China 4 Air Force Engineering Design & Research Bureau, Beijing 100077, China | 2010 | Science China(Technological Sciences)2010，53，7： | 9 |
| 16 | Holocene climate variation denoted by Barkol Lake sediments in northeastern Xinjiang and its possible linkage to the high and low latitude climates显示文摘The climate over the closed inland Barkol Lake,which is located in northeastern Xinjiang Uygur Autonomous Region,is significantly influenced by westerly winds today.To improve our understanding of past climate processes in westerly wind influenced regions in northwestern China,a 250-cm sediment section was retrieved from this lake.After taking the carbon reservoir effect into consideration,the chronological sequence of this section was reconstructed based on seven conventional radiocarbon dates of bulk samples,and the bottom age of this section was determined to be about 9400 cal a BP.Multi-proxy datasets,includingδ18O car,δ13C car of authigenic carbonate,and total organic carbon were examined using wavelet analysis and singular spectrum analysis methods.Results show that the Holocene in the Barkol Lake region can be divided into four stages:(1) a cold and dry early stage before~8000 cal a BP;(2) a moderately warm and wet middle stage between~8000 and 6000 cal a BP;(3) a warm and dry stage,along with a cooling-wetting tendency from 6000 to 2700 cal a BP;and(4) a fluctuating cooling and wet stage between 2700-800 cal a BP,and a drier stage since 800 cal a BP.The general trend of Holocene climatic changes revealed by Barkol Lake sediments was in agreement with that of adjacent regions.We infer that climatic changes during the Holocene in the Barkol Lake region were influenced not only by high latitudes,especially the North Atlantic region climate,but also tropical low-latitude processes,such as the El Nio/La Nia-Southern Oscillation.This study demonstrates that the enhanced activities of ENSO may have played an important role in climatic changes in northeastern Xinjiang during the Holocene.Our results also suggest that climatic patterns may be temporally different in the northern Xinjiang area in response to the changing predominant control of either the Westerly or the Asian summer monsoon,depending on the contrast of their relative strengths. | XUE JiBin & ZHONG Wei 1 School of Geography,South China Normal University,Guangzhou 510631,China 2 Key Laboratory of Oasis Ecology(Ministry of Education) ,Xinjiang University,Urumqi 830046,China 3 Key Laboratory of Western China’s Environmental Systems(Ministry of Education) ,Lanzhou University,Lanzhou 730000,China | 2011 | Science China Earth Sciences2011，54，4： | 8 |
| 17 | 宁夏银川市西夏3号陵园遗址发掘简报显示文摘2000年~2001年,宁夏文物考古研究所等对西夏3号陵园进行了三次发掘,发掘面积2万余平方米。这是西夏陵区帝王陵园地面建筑遗址的第一次系统揭露,出土了大量建筑装饰构件,揭示了陵园月城与陵城垣体、门址、献殿及陵塔、鹊台、角台等建筑的形制、结构和营建规制,为研究西夏建筑、陵寝制度提供了翔实资料。 | NICRA and Yinchuan Municipal Office for the Preservation of the Western Xia Mausoleum Precinct, | 2002 | 考古2002，，8： | 8 |
| 18 | Integrating landscape ecological principles and land evaluation for sustainable land use显示文摘1IntroductionRisingpopulationscompetingforlimitedlandresourceshavefocusedatentionontheneedforincreasingfoodproduction,whilepr... | Fu Bo jie, Chen Li ding Research Centre for Eco Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China He Chan sheng Department of Geography, Western Michigan University, Kalamazoo, MI 49008, USA | 1999 | Journal of Environmental Sciences1999，11，2： | 8 |
| 19 | An extended displacement discontinuity method for analysis of stress wave propagation in viscoelastic rock mass显示文摘An extended displacement discontinuity method (EDDM) is proposed to analyze the stress wave propagation in jointed viscoelastic rock mass (VRM).The discontinuities in a rock mass are divided into two groups.The primary group with an average geometrical size larger than or in the same order of magnitude of wavelength of a concerned stress wave is defined as 'macro-joints',while the secondary group with a high density and relatively small geometrical size compared to the wavelength is known as 'micro-defects'.The rock mass with micro-defects is modeled as an equivalent viscoelastic medium while the macro-joints in the rock mass are modeled explicitly as physical discontinuities.Viscoelastic properties of a micro-defected sedimentary rock are obtained by longitudinally impacting a cored long sedimentary rod with a pendulum.Wave propagation coefficient and dynamic viscoelastic modulus are measured.The EDDM is then successfully employed to analyze the wave propagation across macro-joint in VRM.The effect of the rock viscosity on the stress wave propagation is evaluated by comparing the results of VRM from the presented EDDM with those of an elastic rock mass (ERM) from the conventional displacement discontinuity method (CDDM).The CDDM is a special case of the EDDM under the condition that the rock viscosity is ignored.Comparison of the reflected and transmitted waves shows that the essential rock viscosity has a significant effect on stress wave attenuation.When a short propagation distance of a stress wave is considered,the results obtained from the CDDM approximate to the EDDM solutions,however,when the propagation distance is sufficiently long relative to the wavelength,the effect of rock viscosity on the stress wave propagation cannot be ignored. | L.F.Fan1,F.Ren1,G.W.Ma2 1 School of Civil and Environmental Engineering,Nanyang Technological University,Singapore,639798,Singapore 2 School of Civil and Resource Engineering,The University of Western Australia,Crawley,WA 6009,Australia | 2011 | Journal of Rock Mechanics and Geotechnical Engineering2011，3，1： | 8 |
| 20 | Simulations of explosion-induced damage to underground rock chambers显示文摘A numerical approach is presented to study the explosion-induced pressure load on an underground rock chamber wall and its resultant damage to the rock chamber.Numerical simulations are carried out by using a modified version of the commercial software AUTODYN.Three different criteria,i.e.a peak particle velocity (PPV) criterion,an effective strain (ES) criterion,and a damage criterion,are employed to examine the explosion-induced damaged zones of the underground rock chamber.The results show that the charge chamber geometry,coupling condition and charge configuration affect significantly the dynamic pressure exerted on the rock chamber wall.Thus the chamber is damaged.An inaccurate approximation of pressure boundary ignoring the influences of these factors would result in an erroneous prediction of damaged area and damage intensity of the charge chamber.The PPV criterion yields the largest damaged zone while the ES criterion gives the smallest one.The presented numerical simulation method is superior in consideration of the chamber geometry,loading density,coupling condition and rock quality.The predicted damage intensity of rock mass can be categorized quantitatively by an isotropic damage scalar.Safe separation distance of adjacent chambers for a specific charge weight is also estimated. | G.W.Ma1,H.Hao1,F.Wang2 1 School of Civil and Resource Engineering,The University of Western Australia,Crawley,WA 6009,Australia 2 Defense Science and Technology Agency,Singapore,109679,Singapore | 2011 | Journal of Rock Mechanics and Geotechnical Engineering2011，3，1： | 7 |
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