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1Recent glacial retreat in High Asia in China and its impact on water resource in Northwest China显示文摘Under the impact of climatic warming, the glaciers in the High Asia in China have been retreating continuously with negative glacial mass balance in recent several decades. The retreat became more intensive in the past 10 years. The spatial pattern of the glacial retreat in the High Asia in China is that the smallest magnitude of retreat is in the inland of the Tibetan Plateau, the magnitude increases from the inland to the margin of the Tibetan Plateau, and the largest magnitude at the margin of the Tibetan Plateau. The glacial retreat in the High Asia in China has an important impact on the water resource of the arid regions in Northwest China. This study shows that the glacial retreat in the 1990s has caused an increase of 5.5% in river runoff in Northwest China. In the Tarim River basin, the increase of river runoff is higher than 5.5%.YAO Tandong 1,2 ,WANG Youqing 2 ,LIU Shiying 2,1 ,PU Jianchen 2,1 ,SHEN Yongping 2 & LU Anxin 2,1 1.Institute of Tibetan Plateau Research,Chinese Academy of Sciences,Beijing 100029,China 2.Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,Lanzhou 730000,China 2004Science China Earth Sciences2004,47,12:117
2Function of apoptosis and expression of the proteins Bcl-2,p53 and C-myc in the development of gastric cancer显示文摘INTRODUCTIONIn China ,the incidence and mortality of gastric cancer rank the second among all cancers. Recent development of cancer [1-20].The aim of this study was investigat the insight of apoptosis and bcl-2, p53 and C-myc protein expression in the development of gastric cancer .An Gao Xu Shao Guang Li Ji Hong Liu Ai Hua Gan Research Laboratory of Digestive Disease,Huizhou Central People’s Hospital,Huizhou 516001,Guangdong Province,ChinaDr.An Gao Xu graduated from Guangdong Medical College in 1984.He is an associate physician-in-chief,specializing in the research and treatment of gastrointestinal and liver tumors.He has published 24 papers and 1 book. 2001World Journal of Gastroenterology2001,7,3:91
3Influence of the impounding process of the Three Gorges Reservoir up to water level 172.5m on water eutrophication in the Xiangxi Bay显示文摘The water level of the Three Gorges Reservoir(TGR) rose to 172.5 m in two stages from September to November,2008.The hydrodynamic parameters and water quality parameters(e.g.flow velocity,temperature,turbidity and nutrient content) had been continuously monitored to reveal the influence of the impounding process of the TGR on the water eutrophication in the Xiangxi Bay(XXB).The maximal daily rise of the water level of the TGR was about 2.38 m.The water exchange between the mainstream(the Changjiang River) and the XXB of the TGR was enhanced by density current,and its main characteristics were a density-stratified flow in different directions.The water exchange reduced the differences of the water quality parameters(for example,temperature,turbidity,nutrient level,pH,etc.) between the mainstream and the XXB during the impounding process.Meanwhile,the water stability index in the mainstream remained small but it was lowered in the XXB.The main causes included the dilution by water of lower concentration of the chlorophyll a(Chl.a) entering from the mainstream,the decline of the water stability,and the increase of suspended silt,which induced the Chl.a to decrease in the XXB during the impounding process.The grade of the water eutrophication changed from middle eutrophic level to mesotrophic state in the process.However,as available nutrients were imported into the XXB from the mainstream during the impounding process the risk of water eutrophication increases in the XXB in the future.YANG ZhengJian1,LIU DeFu1,JI DaoBin1,2 & XIAO ShangBin1,3 1 College of Civil & Hydroelectric Engineering,China Three Gorges University,Yichang 443002,China 2 School of Water Resources & Hydropower Engineering,Wuhan University,Wuhan 430072,China 3 Institute of Earth Environment,Chinese Academy of Sciences,Xi’an 710075,China 2010Science China(Technological Sciences)2010,53,4:58
4Characterization for commutators of n-dimensional fractional Hardy operators显示文摘In this paper, it was proved that the commutator Hβ,b generated by an n-dimensional fractional Hardy operator and a locally integrable function b is bounded from Lp1(Rn) to Lp2 (Rn) if and only if b is a C(M)O(Rn) function, where 1/p1 - 1/p2 = β/n, 1 < p1 <∞, 0 ≤β< n. Furthemore,the characterization of Hβ,b on the homogenous Herz space (K)qα,p(Rn) was obtained.Zun-wei FU~(1,2) Zong-guang LIU~3 Shan-zhen LU~(1+) Hong-bin WANG~3 ~1 School of Mathematical Sciences,Beijing Normal University,Beijing 100875,China ~2 Department of Mathematics,Linyi Normal University,Linyi 276005,China ~3 Department of Mathematics,China University of Mining and Technology (Beijing),Beijing 100083,China 2007Science China Mathematics2007,50,10:39
5Grain-size features of a Miocene loess-soil sequence at Qinan: Implications on its origin显示文摘In this study, grain-size of 507 bulk samples from the QA-I Miocene loess-soil sequence at Qinan were analyzed, and the grain-size features are compared with those of typical Quaternary loess and soil samples, representative lacustrine and fluvial samples. The results indicate that the grain-size distribution pattern of the Miocene loess is essentially similar to that of Quaternary loess, but greatly differs from the lacustrine and fluvial sediments. Loess layers are regularly coarser than soil layers, indicating cyclical climate changes. Median grain-size along the 253.1 m sequence varies from 6 to 13 μm and the >63 μm fraction represents only 5.3% in maximum, 0.9% in average. Long-term grain-size variations are consistent with the loess accumulation rate at Qinan and with the eolian mass accumulation rate in the North Pacific. These features firmly indicate an eolian origin of the studied sequence, and also reveal a coeval changes between the long-term changes of eolian grain-size and continental aridity in the dust source regions.QIAO Yansong1,3, GUO Zhengtang2,1, HAO Qingzhen1, YIN Qiuzhen1, YUAN Baoyin1 & LIU Tungsheng1 1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 3. Institute of Geomechanics, Chinese Academy of Geological Sciences, Beijing 100081, China 2006Science China Earth Sciences2006,49,7:33
6Targeting Gene-Virotherapy of Cancer and its prosperity显示文摘为癌症的基因和病毒的治疗显示出一些治疗学的效果,但是有真实突破的缺乏。为了达到肿瘤的完全的消除的目标,在动物的异种皮移植当模特儿,我们开发了叫的新策略指向癌症的 Gene-Virotherapy,它试图联合基因治疗和 virotherapy 的优点。这新策略独自比基因或病毒的治疗生产了更强壮的反肿瘤效果。肿瘤特定的 replicative 侵入人体气管粘膜的病菌向量,指定了为 ZD55,被侵入人体气管粘膜的病菌的 55kDa E1B 区域的删除构造。结果病毒的构造不仅由明确地指向 p53 保留类似的功能到 ONYX-015 否定肿瘤,而且允许各种各样的治疗学的基因到的插入由于最新介绍的克隆的地点形成适当 ZD55 衍生物,与原来的 ONYX-015 病毒不可行的一项任务。我们证明反肿瘤一如此的衍生物完成, ZD55-IL-24,比 ZD55 virotherapy 或 Ad-IL-24 基因治疗的是乘更多的有势力的至少 100。不过,由 ZD55-IL-24 的使用的肿瘤质量的完全的消除是仅仅在一些然而并非所有老鼠观察了,显示那一治疗学的基因不对“痊愈”足够这些老鼠。有互补或合作的效果的基因是什么时候,独立克隆进 ZD55 向量并且在联合使用了(指定了为双基因治疗策略) ,好一些的结果被获得;并且如果二合适的基因被选择,在所有老鼠完成所有异种皮移植肿瘤群众的完全的消除是可能的。更全面的研究将多半为临床的试用基于这新策略导致一个协议。最后,为癌症治疗的两倍控制指向的病毒双的基因治疗的概念,和在癌症干细胞的最近的进步的含意也被讨论。Xin Yuan Liu~(1,2) ~1Institute of Biochemistry and Cell Biology,Shanghai Institutes for Biological Sciences,Chinese Academy of Sciences,320 Yue Yang Road,Shanghai 200031,China ~2Xinyuan Institute of Medicine and Biotechnology,School of Life Science,Zhejiang Sci-Tech University,Hangzhou 310018,China 2006Cell Research2006,16,11:32
7Fuzzy c-means clustering with non local spatial information for noisy image segmentation显示文摘Feng Zhao (1) add_zf1119@hotmail.com Licheng Jiao (1) Hanqiang Liu (1) 2011Frontiers of Computer Science2011,5,1:31
8The abnormal expression of retinoic acid receptor-β,p53 and Ki67 protein,n normal,premalignant and malignant esophageal tissues显示文摘AIM: Esophageal cancer remains a significant healthiproblem worldwide. It is important to investigate alterationsin expression of retinoic acid receptor-β, p53 and Ki67proteins in esophageal carcinogenesis.METHODS: To find biomarkers for early identification ofesophageal cancer, we analyzed the retinoic acid receptor-j3,p53 protein and the proliferation marker Ki67 in surgicalspecimens of normal, mildly, and severely dysplastic andmalignant esophageal tissues by in situ hybridization ofRNA and immunohistochemistry.RESULTS: RAR-β was expressed in 94.3 %(33/35) of normalmucosae, 67.8 %(19/28) of the mild, 58.1% (18/31) of thesevere ieaions and 53.2 % (116/218) of tumor samples. RAR-β mRNA was expressed in 62.7 % (42/67), 55.1% (43/78) and29.2 % (7/24) of well, moderated and poorly differentiatedSSCs. The p53 and Ki67 proteins were 5.9 % (2/34) of thenormal mucosa. P53 and Ki67 stained positively in 10.7 % (3/28) and 21.4 % (6/28) of mild dysplasia, and 51.6 %(16/31)and 58. 1% (18/31) of severely dysplasia respectively.Samples from esophageal cancer showed no higher levers ofp53 and Ki67 expression than seen in severely dysplasticlesions. There was significant difference of RAR-β、 p53 andKi67 expression between normal mucosa and dysplatictissue or esophageal cancer.CONCLUSION: Loss of RAR-β expression and acctnulation ofp53 and Ki67 proteins may serve as biomarkers for earlyidentification of esophageal cancer in the high-riskpopulations.Min Xu Sheng-Zu Chen,Department of Nuclear Medcine,Cancer Hospital(Institute),Peking Union Medical College and Chinese Academy of Medical Sciences,Beijing 10002,1,China Yu-Lan Jin Jun Fu Hong Huang Ping Qu Hai-Mei Tian ZhaoYang Liu Wei Zhang,Central Laboratory for Tumor Biology,Cancer Hospital(Institute),Peking Union Medical College and Chinese Academy of Medical Sciences,Beijing 100021,China 2002World Journal of Gastroenterology2002,8,2:34
9Draining Tangjiashan Barrier Lake after Wenchuan Earthquake and the flood propagation after the dam break显示文摘Tangjiashan Barrier Lake is one of the largest barrier lakes caused by the Wenchuan Earthquake. Its risk analysis, emergency plan and effect of the emergency plan are introduced in this paper. The dam height of Tangjiashan Barrier Dam is about 105 m, and the reservoir storage capacity is 3.2×108 m3. When the dam broke the flood peak were estimated to be larger than 48000 m3/s, which might cause a enormous disaster to the downstream cities and residents. A discharge channel with 13 m deep and 8 m wide was drug, so that the water may flow out of the lake before the dam breaks. As a result, the drainage and risk mitigation project are successful. During the drainage process, the flood peak was about 6500 m3/s, and about 1.6×108 m3 of water was drained off and the residual reservoir capacity was only 8.97×107 m3. A new channel with average width 100 m was formed, which can bear floods of 200 years frequency. The successful experience and the collected data can be used to deal with the similar natural disasters in future.LIU Ning1, ZHANG JianXin2, LIN Wei3, CHENG WuYI4 & CHEN ZuYu5 1 Ministry of Water Resources of the People’s Republic of China, Beijing 100053, China 2 Bureau of Hydrology of the Ministry of Water Resources of the People’s Republic of China, Beijing 100053, China 3 Sichuan Hydrographic and Water Resources Survey Bureau Chengdu 610031, China 4 HydroChina Chengdu Engineering Corporation, Chengdu 610072, China 5 China Institute of Water Resources and Hydropower Research, Beijing 100044, China 2009Science China(Technological Sciences)2009,52,4:29
10Invasive mechanism and management strategy of Bemisia tabaci(Gennadius) biotype B:Progress report of 973 Program on invasive alien species in China显示文摘Bemisia tabaci(Gennadius) biotype B,called a 'superbug',is one of the most harmful biotypes of this species complex worldwide.In this report,the invasive mechanism and management of B.tabaci biotype B,based on our 5-year studies,are presented.Six B.tabaci biotypes,B,Q,ZHJ1,ZHJ2,ZHJ3 and FJ1,have been identified in China.Biotype B dominates the other biotypes in many regions of the country.Genetic diversity in biotype B might be induced by host plant,geographical conditions,and/or insecticidal application.The activities of CarE(carboxylesterase) and GSTs(glutathione-S-transferase) in biotype B reared on cucumber and squash were greater than on other host plants,which might have increased its resistance to insecticides.The higher activities of detoxification enzymes in biotype B might be induced by the secondary metabolites in host plants.Higher adaptive ability of biotype B adults to adverse conditions might be linked to the expression of heat shock protein genes.The indigenous B.tabaci biotypes were displaced by the biotype B within 225 d.The asymmetric mating interactions and mutualism between biotype B and begomoviruses via its host plants speed up widespread invasion and displacement of other biotypes.B.tabaci biotype B displaced Trialeurodes vaporariorum(Westwood) after 4-7 generations under glasshouse conditions.Greater adaptive ability of the biotype B to adverse conditions and its rapid population increase might be the reasons of its successful displacement of T.vaporariorum.Greater ability of the biotype B to switch to different host plants may enrich its host plants,which might enable it to better compete with T.vaporariorum.Native predatory natural enemies possess greater ability to suppress B.tabaci under field conditions.The kairomones in the 3rd and 4th instars of biotype B may provide an important stimulus in host searching and location by its parasitoids.The present results provide useful information in explaining the mechanisms of genetic diversity,evolution and molecular eco-adaptation of biotype B.Furthermore,it provides a base for sustainable management of B.tabaci using biological and ecological measures.WAN FangHao1,ZHANG GuiFen1,LIU ShuSheng2,LUO Chen3,CHU Dong4,ZHANG YouJun4,ZANG LianSheng2,JIU Min2,Lü ZhiChuang1,CUI XuHong1,ZHANG LiPing4,ZHANG Fan3,ZHANG QingWen5,LIU WanXue1,LIANG Pei5,LEI ZhongRen1 & ZHANG YongJun1 1 State Key Laboratory for Biology of Plant Diseases and Insect Pests,Institute of Plant Protection,Chinese Acadeny of Agriculture Sciences,Beijing 100094,China 2 Institute of Applied Entomology,Zhejiang University,Hangzhou 310029,China 3 Institute of Plant and Environment Protection,Beijing Academy of Agricultural and Forestry Sciences,Beijing 100089,China 4 Institute of Vegetables and Flowers,Chinese Acadeny of Agricullare Sciences,Beijing 100081,China 5 Department of Entomology,China Agriculture University,Beijing 100094,China 2009Science China(Life Sciences)2009,52,1:30
11Genetic analysis and gene mapping of a new rolled-leaf mutant in rice (Oryza sativa L.)显示文摘To understand the development of rice leaf blades,we identified a new rolled-leaf mutant,w32,from indica cultivar IR64 through EMS mutagenesis. The mutant showed a stable rolled-leaf phenotype throughout the life cycle. Two F2 populations were developed by crossing w32 to cultivar IR24 and PA64. Genetic analysis showed that the rolled-leaf phenotype was controlled by a single recessive gene. To determine the location of the gene,bulked segregant analysis was carried out using mutant and wild-type DNA pools and 1846 mutant-type F2 individuals derived from the cross w32/PA64 were genotyped to locate the gene on the short arm of chromosome 7. The rolled-leaf gene,tentatively named rl11(t),is likely a new gene as no other rolled-leaf genes have been identified near the region. By developing new SSR and InDel markers,the gene was delimited to a 52 kb region near the end of the short chromosome arm. Further fine mapping and cloning of the gene are currently underway.SHI YongFeng1,2,CHEN Jie1,LIU WenQiang1,HUANG QiNa1,2,SHEN Bo2,LEUNG Hei3 & WU JianLi1 1 Chinese National Center for Rice Improvement/National key Laboratory for Rice Biology,China National Rice Research Institute,Hangzhou 310006,China 2 College of Life and Environmental Sciences,Hangzhou Normal University,Hangzhou 310016,China 3 International Rice Research Institute,Metro Manila DAPO Box 7777,Philippines 2009Science China(Life Sciences)2009,52,9:29
12Production of proinflammatory cytokines in the human THP-1 monocyte cell line following induction by Tp0751,a recombinant protein of Treponema pallidum显示文摘The tissue destruction characteristic of syphilis infection may be caused by inflammation due to Treponema pallidum and the ensuing immune responses to the pathogen.T.pallidum membrane proteins are thought to be potent inducers of inflammation during the early stages of infection.However,the actual membrane proteins that induce inflammatory cytokine production are not known,nor are the molecular mechanisms responsible for triggering and sustaining the inflammatory cascades.In the present study,Tp0751 recombinant protein from T.pallidum was found to induce the production of proinflammatory cytokines,including TNF-α,IL-1βand IL-6,in a THP-1 human monocyte cell line.The signal transduction pathways involved in the production of these cytokines were then further investigated.No inhibition of TNF-a,IL-1β,or IL-6 production was observed following treatment with the SAPK/JNK specific inhibitor SP600125 or with an ERK inhibitor PD98059.By contrast,anti-TLR2 mAb,anti-CD14 mAb,and the p38 inhibitor SB203580 significantly inhibited the production of all three cytokines.In addition,pyrrolidine dithiocarbamate (PDTC),a specific inhibitor of NF-κB,profoundly inhibited the production of these cytokines.Tp0751 treatment strongly activated NF-κB,as revealed by Western blotting.However,NF-κB translocation was significantly inhibited by treatment with PDTC.These results indicated that TLR2,CD14,MAPKs/p38,and NF-κB might be implicated in the inflammatory reaction caused by T.pallidum infection.LIU ShuangQuan1,2,WANG ShiPing1,WU YiMou3,ZHAO FeiJun3,ZENG TieBing3,ZHANG YueJun3,ZHANG QiuGui2 & GAO DongMei1 1 Department of Parasitology,Xiangya School of Medicine,Central South University,Changsha 410078 ,China 2 The First Affiliated Hospital,University of South China,Hengyan 421001,China 3 Department of Microbiology and Immunology,University of South China,Hengyan 421001,China 2010Science China(Life Sciences)2010,53,2:28
13Development of Finite Element Limiting Analysis Method and Its Applications in Geotechnical Engineering显示文摘The Finite Element Limiting Analysis Method(LELAM) has the advantage of combining a numerical analysis method with traditional limiting equilibrium methods.It is particularly applicable to the analysis and design of geotechnical engineering.In the early 20th century,FELAM has been developed vigorously in domestic geotechnical engineering over international common finite element procedures.It has made great achievements in basic theory research and computational precision,thus broadening the application fields in practical projects.In order to gradually make innovations in geotechnical design methods,some of our research results are presented,mainly including geotechnical safety factor definitions,the principles for use of the method concerned,the overall failure criterion,the deduction and selection of the yield criterion,and the measurement to improve the computational precision,etc..The application field has been broadened from two-dimensional to three-dimensional,from soil slope to jointed rock slope and foundation,from stable seepage to non-stable seepage,from slope and foundation to tunnel.This method has also been used in search of many hidden sliding surfaces of complex landslides,conducting the structural support design considering the interaction between the soil and the structure,and computing simulation foundation bearing plates load tests,etc..Zheng Yingren1,Deng Chujian1,Zhao Shangyi1,Tang Xiangsong1,Liu Mingwei1,Zhang Liming2(1 Department of Civil Engineering,Logistical Engineering University,Chongqing 400041,China 2 Department of Science and Information Engineering,Qingdao Technological University,Qingdao 266033,China) 2007工程科学(英文版)2007,5,3:27
14Protective mechanism of desiccation tolerance in Reaumuria soongorica: Leaf abscission and sucrose accumulation in the stem显示文摘Reaumuria soongorica (Pall.) Maxim., a perennial semi-shrub, is widely found in semi-arid areas in northwestern China and can survive severe desiccation of its vegetative organs. In order to study the protective mechanism of desiccation tolerance in R. soongorica, diurnal patterns of net photosynthetic rate (Pn), water use efficiency (WUE) and chlorophyll fluorescence parameters of Photosystem II (PSII), and sugar content in the source leaf and stem were investigated in 6-year-old plants during progressive soil drought imposed by the cessation of watering. The results showed that R. soongorica was char-acterized by very low leaf water potential, high WUE, photosynthesis and high accumulation of sucrose in the stem and leaf abscission under desiccation. The maximum Pn increased at first and then de-clined during drought, but intrinsic WUE increased remarkably in the morning with increasing drought stress. The maximal photochemical efficiency of PSII (Fv/Fm) and the quantum efficiency of noncyclic electric transport of PSII(ΦPSII) decreased significantly under water stress and exhibited an obvious phenomenon of photoinhibition at noon. Drought stressed plants maintained a higher capacity of dis-sipation of the excitation energy (measured as NPQ) with the increasing intensity of stress. Conditions of progressive drought promoted sucrose and starch accumulation in the stems but not in the leaves. However, when leaf water potential was less than –21.3 MPa, the plant leaves died and then abscised. But the stem photosynthesis remained and, afterward the plants entered the dormant state. Upon re-watering, the shoots reactivated and the plants developed new leaves. Therefore, R. soongorica has the ability to reduce water loss through leaf abscission and maintain the vigor of the stem cells to survive desiccation.LIU YuBing1,2, ZHANG TengGuo1, LI XingRong2 & WANG Gang1 1 School of Life Sciences, Lanzhou University, Lanzhou 730000, China 2 Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China 2007Science China(Life Sciences)2007,50,1:27
15NUMERICAL SIMULATION OF ROUND TO OVAL ROLLING PROCESS显示文摘Three dimensional thermal-mechanical coupled elasto-plastic FEM has been used for simulation of round to oval single pass rolling. The analysis was conducted using MARC/AUTOFORCE1. 2 code. The material is assumed to be elasto-plastic and it obey the Von Mises yield criterion and Prandtl- Reuss rule. Deformation of the workpiece is simulated in a step-by-step manner,updating the coordinates of material points and the property after each step, so that both nonsteady-state and stendy-state deformation can be simulated. The heat transfter between the workpiece, the rolls, and enviroment and the heat generation due to plastic work and friction force, are considered in the analys- is.Predicted the deformation shape of the workpiece, distributions of strains, stresses, strain rates and temperatures, roll-separating force and roll torque are presented.Y. W. Wang, Y. L. King, D. H. Yuan, S. G. Liu and Z. Y. Yu 1 ) University of Science and Technology Beijing, Beijing 100083, China 2) Daye Special Steel Co., Huangshi 435001, China 2000Acta Metallurgica Sinica(English Letters)2000,13,2:27
16Hepatitis C virus infection of human hepatoma cell line 7721 in vitro显示文摘AIM To establish a cell culture system with long-term replication of hepatitis C virus in vitro.``METHODS Human hepatoma cell line 7721 was tested for its susceptibility to HCV by incubating with a serum from a patient with chronic hepatitis C. Cells and supernatant were harvested at various phases during the culturing periods The presence of HCV RNA, the expression of HCV antigens in cells and/or supernatant were examined by RT-PCR, in situ hybridization and immunohistochemistry respectively.``RESULTS The intracellular HCV RNA was first detected on d 2 after infection and then could be intermittently detected in both cells and supernatant over a period of at least three months. The expression of HCV NS3, CP10antigens could be observed in cells. The fresh cells could be infected by supematant from cultured infected cells and the transmission of viral genome from HCV-infected 7721 cells to PBMCs was also observed.``CONCLUSION The hepatoma line 7721 is not only susceptible to HCV but also supports its long-term replication in vitro.Zhi-Qiang Song~1 Fei Hao~1 Feng Min~2 Qiao-Yu Ma~2 Guo-Dong Liu~2 Department of Dermatology~1Department of Infectious Diseases~2,Southwest Hospital,Third Military Medical University,Chongqing 400038,China 2001World Journal of Gastroenterology2001,7,5:26
17The influence of moderate ENSO on summer rainfall in eastern China and its comparison with strong ENSO显示文摘The 6 major ENSO events since 1979 are classified into the strong and moderate ENSO based on in-tensity. The composite analysis is performed to reveal the influence of ENSO on East Asian summer monsoon (EASM) and summer rainfall in eastern China. It is shown that the influence is changed with the seasonal cycle in summer, with a weaker influence in June and a stronger influence in August, in-dicating a long lagged effect of ENSO on EASM. Besides, the circulation and rainfall anomalies caused by the strong ENSO are also stronger with an earlier starting time, while the influence of the moderate ENSO is evident in August. The composite summer rainfall in eastern China for the moderate ENSO exhibits a northern rainfall pattern, which is totally different from the classical ENSO-type rainfall pat-tern. Based on the composite analysis, two moderate ENSO years with a similar intensity (i.e., 1995 and 2003) are compared. The result shows that, the response of EASM to the moderate ENSO during June and July is, to a certain degree, modulated by the circulation systems in mid-high latitudes of Eurasia and in the Southern Hemisphere, thereby inducing a different rainfall distribution in eastern China. In comparison with the strong ENSO in 1983, it is further revealed that, the strong ENSO plays a dominant role in summer rainfall anomalies in eastern China as well as in controlling the influence of the other factors on EASM. The strong ENSO is therefore different with the moderate ENSO.XUE Feng1 & LIU ChangZheng1,2 1 Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China 2008Chinese Science Bulletin2008,53,5:25
18Total alkyl dibenzothiophenes content tracing the filling pathway of condensate reservoir in the Fushan Depression,South China Sea显示文摘The condensates are generally characterized by high maturity,low concentration of steranes and ter-panes biomarkers and low content of non-hydrocarbon fraction. In this case commonly used steranes,terpanes and carbazoles parameters cannot be effectively applied in the reservoir-filling tracing. The hydrogen bond formed by sulfur atom in the dibenzothiophenes (DBTs) results in molecule adsorption and fractionation during oil migration in reservoir. Like carbazoles,total DBTs content decreases with the increasing of oil migration distance. Therefore,a new parameter——total DBTs content is proposed to be used to trace the oil migration orientation and filling pathway. In present study,total DBTs con-tents of condensates and light oils are obtained by adding internal standard——eight deuterium atoms substituted DBT during Gas Chromatography-Mass Spectrometry analysis of aromatic fraction. Except for a few samples with much lower content of non-hydrocarbon fraction,the total DBTs content shows a fine positive correlation with that of carbazoles. Large errors can be caused in the process of pyrrolic nitrogen compounds separation. The application of this new parameter in the Fushan Depression of Beibu Gulf Basin,South China Sea indicates that this parameter is a reliable one to trace filling pathway in condensate reservoirs. Combined with other DBTs-related parameters,such as 4-/1-methydibenzo-thiophene and 2,4-/1,4-dimethyldibenzothiophene,oil migration orientation and filling pathway of the Fushan Depression was determined. The accumulations of Huachang oil field in the Fushan Depres-sion are mainly migrated and charged from northeast to southeast along the Huachang uplift. It can be predicated that the light oil and condensates in the Huachang oil field should be sourced from the source kitchen at the Bailian Sag. It shows that total DBTs content is an effective parameter to tracing oil migration orientation and filling pathway.LI MeiJun1,WANG TieGuan1,LIU Ju2,ZHANG MeiZhu2,LU Hong3,MA QinLin2 & GAO LiHui2 1 State Key Laboratory of Petroleum Resources and Prospecting,Earth Sciences and Geoinformatics School,China University of Petroleum,Beijing 102249,China 2 Southern Oil Exploration and Development Company,PetroChina,Guangzhou 510640,China 3 Guangzhou Institute of Geochemistry,Chinese Academy of Sciences,Guangzhou 510240,China 2008Science China Earth Sciences2008,51,S2:24
19Plasmacytoid dendritic cells in antiviral immunity and autoimmunity显示文摘Plasmacytoid dendritic cells (pDCs) represent a unique and crucial immune cell population capable of producing large amounts of type I interferons (IFNs) in response to viral infection.The function of pDCs as the professional type I IFN-producing cells is linked to their selective expression of Toll-like receptor 7 (TLR7) and TLR9,which sense viral nucleic acids within the endosomal compartments.Type I IFNs produced by pDCs not only directly inhibit viral replication but also play an essential role in linking the innate and adaptive immune system.The aberrant activation of pDCs by self nucleic acids through TLR signaling and the ongoing production of type I IFNs do occur in some autoimmune diseases.Therefore,pDC may serve as an attractive target for therapeutic manipulations of the immune system to treat viral infectious diseases and autoimmune diseases.TANG Fei1,2,DU Qiumei1,2 & LIU Yong-Jun3 1 Center for Infection and Immunity,Institute of Biophysics,Chinese Academy of Sciences,Beijing 100101,China 2 Graduate University of Chinese Academy of Sciences,Beijing 100049,China 3 Department of Immunology and Center for Cancer Immunology Research,University of Texas,M.D.Anderson Cancer Center,Houston,Texas 77030,USA 2010Science China(Life Sciences)2010,53,2:23
20Discovery of Paleogene marine stratum along the southern side of Yarlung-Zangbo suture zone and its implications in tectonics显示文摘The Jiachala Formatiom is a new lithostratigraphic unit set up in this paper. This is the first report on the Paleogene marine sequences and microfaunas in Gyangze to the southern side of the Yarlung-Zangbo suture zone. On the basis of fossil abundance, species diversity, dominant species and first and last occurrences of key species, three dinoflagellate assemblages and three polynological assemblages were recognized in the Jiachala Formatiom. They are in ascending order as follows: Apectodinium quinquelatum-Apectodinium hyperacanthum, Cannin- gia chinensis-Palaeoperidinium pyrophorum and Cymatiosphaera reticulosa-Samlandia chla- mydophora dinoflagellate assemblages, and Arliaceoipollenites baculatus-Anacolosidites sub- trudens, Aglaoreidia cyclops-Pinuspollenites microinsigis, and Elaeangnacites asper-Ilexpol- lenites iliacus polynological Assemblages. According to the assemblages, the age of the Jiachala Formation is referred to Paleocene-early Eocene. The preliminary study on the Jiachala Forma- tion shows that this group of Paleogene deposits accumulated in an underfilled peripheral fore- land basin which was in response to the load of the crust thickening resulted from the Asia-India collision. The stratigraphic evidences provided by the evolution of foreland basin indicate that the India-Asia initional collision should occure near the Cretaceous/Paleogene boundary. The de- velopment and evolution of the southern Tibet foreland basin was under the control of the stress field from the subduct-collision between India and Asia and the structure pattern of the basement. The withering of Tethys Sea might occur after early Eocene in the Gyangze basin and should be after Priabonian of late Eocene in southern Tibet.LI Guobiao 1 , WAN Xiaoqiao 1 , LIU Wencan 1 , LIANG Dingyi 1 & Hyesu Yun 2 1. China University of Geosciences, Beijing 100083, China 2. Chungnam National University, Daejon, 305-350, Korea 2005Science China Earth Sciences2005,48,5:21
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