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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
3Source mechanism of strong aftershocks (M_s≥5.6) of the 2008/05/12 Wenchuan earthquake and the implication for seismotectonics显示文摘Dozens of >M5, hundreds of >M4, and much more >M3 aftershocks occurred after the 2008/05/12 Wenchuan earthquake, which were well recorded by permanent and portable seismic stations. After relocated with P arrival, the >M3 aftershocks show two trends of distribution, with most of the aftershocks located along the north-east strike consistent with Longmenshan fault system, yet there is a north-west trend around the epicenter. It seems that substantially more aftershocks occur in regions with crystalline bedrocks. Then we collected waveform data from National Digital Seismograph Network and regional seismograph network of China, and employed 'Cut and Paste' method to obtain focal mechanisms and depths of the big aftershocks (M≥5.6). While most of those aftershocks show thrust mechanism, there are some strike slip earthquakes in the northern-most end of the rupture. Focal mechanisms show that the events located on the southern part of central Beichuan-Yingxiu Fault (BY) are mainly thrust earthquakes, which is consistent with initial mechanism of the main shock rupture. In the north part the aftershocks along the BY are also dominated by thrust slip, which is quite different from the right slip rupture of the main shock. Around Qingchuan-Pingwu Fault, the focal mechanisms are dominated by right-slip rupture with large depths (~18 km). So we suspected that in the north part the main shock might rupture on two faults: Beichuan Fault and Qingchuan-Pingwu Fault. The complex pattern of aftershock mechanisms argues for presence of a complicated fault system in the Longmenshan area.ZHENG Yong1,2,MA HongSheng3,Lü Jian4,NI SiDao5,LI YingChun6 & WEI ShengJi2 1 Institute of Geodesy and Geophysics,Chinese Academy of Sciences,Wuhan 430077,China 2 Institute of Geophysics,Chinese Earthquake Administration,Beijing 100086,China 3 Institute of Earthquake Science,Chinese Earthquake Administration,Beijing 100086,China 4 Earthquake Administration of Jiangxi Province,Nanchang 330039,China 5 School of Earth and Space Science,University of Science and Technology of China,Hefei 230026,China 6 Earthquake Administration of Jiangsu Province,Nanjing 210014,China 2009Science China Earth Sciences2009,52,6:100
4S-rough sets and knowledge separation显示文摘The conceptions of the knowledge screen generated by S-rough sets are given: f- screen and - screen , and then puts forward - filter theorem, - filter theorem of knowledge. At last, the applications of knowledge separation are given according to - screen and - screen.Shi Kaiquan 1,21. School of Mathematics and System Sciences, Liaocheng University, Liaocheng 252059, P. R. China 2. School of Mathematics and System Sciences, Shandong University, Jinan 250100, P. R. China 2005Journal of Systems Engineering and Electronics2005,16,2:104
5我国面临快速增长的终末期肾病治疗负担显示文摘目的报告2008年我国终末期肾脏病维持性透析患病率和发病率,并估计未来维持性透析的趋势。方法中国医院协会血液净化中心管理分会制定调查表,以透析登记软件及纸质版形式下发至各省、自治区和直辖市的血液净化中心管理分会/血液净化质量控制中心,收集各透析室的数据,包括2007年底和2008年底患者数量,以及2008年新进入透析的患者数量;患者的性别和年龄构成;导致终末期肾脏病(ESRD)的原因以及所有死亡患者的原因。分析2007和2008年底ESRD的点患病率、2008年ESRD发病率、ESRD病因以及死亡原因构成。结果全国31个省、自治区和直辖市中,27个应答。2007年底,共报告65074例ESRD患者,点患病率为每百万人口51.7;2008年底患者数增至102863例,点患病率为每百万人口79.1,患病率增长52.9%。2008年ESRD新患者数为45423例,发病率每百万人口36.1。ESRD的病因依次为肾小球肾炎(45%)、糖尿病(19%)、高血压(13%)、多囊肾病(2%)和其他或未知(20%)。ESRD主要死亡原因是心血管疾病(31%)、中风(20.3%)、感染(19.9%)和其他(28.8%)。结论虽然我国ESRD的患病率显著低于其他亚洲国家和地区,但发病率极高,未来几年患病率也将快速增加,从而增加我国ESRD的治疗负担。Li Zuo M.D.1 and Mei Wang M.D.2 for Chinese Society of Blood Purification Institute of Nephrology,Peking University First 1 Hospital Institute of Nephrology,Peking University People’s Hospital 2 2010中国血液净化2010,,1:145
6Spatiotemporal variations of vegetation cover on the Chinese Loess Plateau(1981―2006):Impacts of climate changes and human activities显示文摘Spatiotemporal variations of Chinese Loess Plateau vegetation cover during 1981-2006 have been investigated using GIMMS and SPOT VGT NDVI data and the cause of vegetation cover changes has been analyzed, considering the climate changes and human activities. Vegetation cover changes on the Loess Plateau have experienced four stages as follows: (1) vegetation cover showed a continued increasing phase during 1981―1989; (2) vegetation cover changes came into a relative steady phase with small fluctuations during 1990―1998; (3) vegetation cover declined rapidly during 1999―2001; and (4) vegetation cover increased rapidly during 2002―2006. The vegetation cover changes of the Loess Plateau show a notable spatial difference. The vegetation cover has obviously increased in the Inner Mongolia and Ningxia plain along the Yellow River and the ecological rehabilitated region of Ordos Plateau, however the vegetation cover evidently decreased in the hilly and gully areas of Loess Plateau, Liupan Mountains region and the northern hillside of Qinling Mountains. The response of NDVI to climate changes varied with different vegetation types. NDVI of sandy land vegetation, grassland and cultivated land show a significant increasing trend, but forest shows a decreasing trend. The results obtained in this study show that the spatiotemporal variations of vegetation cover are the outcome of climate changes and human activities. Temperature is a control factor of the seasonal change of vegetation growth. The increased temperature makes soil drier and unfavors vegetation growth in summer, but it favors vegetation growth in spring and autumn because of a longer growing period. There is a significant correlation between vegetation cover and precipitation and thus, the change in precipitation is an important factor for vegetation variation. The improved agricultural production has resulted in an increase of NDVI in the farmland, and the implementation of large-scale vegetation construction has led to some beneficial effect in ecology.XIN ZhongBao1,2, XU JiongXin1 & ZHENG Wei1, 2 1 Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 2 Graduate University of the Chinese Academy of Sciences, Beijing 100049, China 2008Science China Earth Sciences2008,51,1:112
7Apoptosis and its relationship with cell proliferation,p53,Waf1p21,bcl-2 and c-mycin esophageal carcinogenesis studied with a high-risk population in northern China显示文摘Apoptosisanditsrelationshipwithcelproliferation,p53,Waf1p21,bcl2andcmycinesophagealcarcinogenesisstudiedwithahighriskpopul...WANG LiDong1, ZHOU Qi1, WEI JunPing1, YANG WanCai1, ZHAO Xin1, WANG LiXia1, ZOU Jian Xiang1, GAO ShanShan1, LI YongXin1 and YANG C.S.2Keywords esophageal neoplasms apoptosis precancerous lesions Waf1 p21 gene p53 1998World Journal of Gastroenterology1998,4,4:295
8Growth inhibition and apoptosis induction Sulindac on Human gastric cancer cells显示文摘AIM: To evaluate the effects of sulindac in inducing growth inhibition and apoptosis of human gastric cancer cells in comparison with human hepatocellular carcinoma (HCC)cells.METHODS: The human gastric cancer cell lines MKN45 and MKN28 and human hepatocellular carcinoma cell lines HepG2and SMMC7721 were used for the study. Anti-proliferative effect was measured by MTT assay, and apoptosis was determined by Hoechst-33258 staining, electronography and DNA fragmentation. The protein of cyclooxygenase-2 (COX(2) and Bcl-2 were detected by Westem dot blotting.RESULTS: Sulindac could initiate growth inhibition and apoptosis of MKN45, MKN28, HepG2 and SMMC7721 cells in a dose-and time-dependent manner. Growth inhibitory activity and apoptosis were more sensitive in HepG2 cells than in SMMC7721 cells, MKN45 and MKN28 cells. After 24hours incubation with sulindac at 2mmol. L-1 and 4mmol.L-1, the level of COX-2 and Bcl-2 protein were lowered in MKN45, SMMC7721 and HepG2 cells but not in MKN28 cells.CONCLUSION: Sulindac could inhibit the growth of gastric cancer cells and HCC cells effectively in vitro by apoptosis induction, which was associated with regression of COX-2and Bcl-2 expression. The growth inhibition and apoptosis of HCC cells were greater then that of human gastric cancer cells. The different effects of apoptosis in gastric cancer cells may be related to the differentiation of the cells.Yun-Lin Wu~1 Bo Sun~1 Xue-Jun Zhang~2 Sheng-Nian Wang~2 Heng-Yi He~2 Min-Min Qiao~1 Jie Zhong~1 Jia-Yu Xu~1 1 Department of Gastroenterology,Ruijin Hospital,Shanghai Second Medical University,Shanghai 200025,China2 Institude of Biochemistry and Cell Biology,Shanghai Institues for Biological Sciences,Chinese Academy of Sciences.Shanghai 200025,China 2001World Journal of Gastroenterology2001,7,6:64
9SHRIMP dating of the Bangong Lake SSZ-type ophiolite: Constraints on the closure time of ocean in the Bangong Lake-Nujiang River,northwestern Tibet显示文摘The Bangong Lake ophiolite is located in the westernmost part of the Bangong Lake-Nujiang River suture zone. It is a tectonic mélange consisting of numerous individual blocks of peridotite, pillowed and massive lavas and mafic dykes with SSZ-type ophiolitic geochemical affinity formed at the end of a Wilson circle. The SHRIMP U-Pb ages of the co-magmatic zircon domains from one gabbroic dyke (Sample 01Y-155) range from 162.5±8.6 Ma to 177.1±1.4 Ma with an average of 167.0±1.4 Ma (n = 12, MSWD = 1.2), suggesting that the subduction of the Bangong Lake Neo-Tethyan Ocean started before the Middle Jurassic. It is inferred that the tectonic transform from spreading to subduction of the Neo-Tethyan Ocean began before the Middle Jurassic in the Bangong Lake area.SHI RenDeng1,2 1 School of Earth and Space Sciences, University of Science and Technology of China, Hefei 230026, China 2 Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China (email: shird@ustc.edu.cn) 2007Chinese Science Bulletin2007,52,7:70
10Function S-rough sets and security-authentication of hiding law显示文摘Function S-rough sets are defined by R-function equivalence class, which have dynamic characteristic. Function S-rough sets have dynamic characteristic, law characteristic and law-hiding characteristic. Function S-rough sets can generate f-hiding law and - hiding law. By engrafting, crossing, and penetrating between the information security theory and function S-rough sets, the security hiding and the authentication of f- hiding law and - hiding law are given respectively in this paper. The fusion and share between function S-rough sets and information security theory is a new research direction of the application of information law in information system.SHI KaiQuan1,2 & ZHAO JianLi3 1 School of Mathematics and Computer Sciences, Longyan University, Longyan 364000, China 2 School of Mathematics and System Sciences, Shandong University, Jinan 250100, China 3 School of Mathematics Science, Liaocheng University, Liaocheng 252059, China 2008Science in China(Series F)2008,51,7:69
11Weighted composition operators between μ-Bloch spaces on the unit ball显示文摘In this paper, necessary and sufficient conditions are given for the weighted composition operator Tψ,ψ to be bounded or compact from the spaceβμ to βv, (or βμ,o to βv,o) on the unit ball of Cn. At the same time, a series of corollaries are also obtained.ZHANG Xuejun~1 & XIAO Jianbin~2 1. College of Mathematics and Computer Science,Hunan Normal University,Changsha 410006,China(email:xuejunttt@263. net) 2. The School of Science,Hangzhou Dianzi University,Hangzhou 310037,China 2005Science China Mathematics2005,48,10:49
12Control of atmospheric CO_2 concentrations by 2050: A calculation on the emission rights of different countries显示文摘This paper is to provide quantitative data on some critical issues in anticipation of the forthcoming international negotiations in Denmark on the control of atmospheric CO2 concentrations. Instead of letting only a small number of countries dominate a few controversial dialogues about emissions reductions, a comprehensive global system must be established based on emissions allowances for different countries, to realize the long-term goal of controlling global atmospheric CO2 concentrations. That a system rooted in 'cumulative emissions per capita,' the best conception of the 'common but differentiated responsibilities' principle affirmed by the Kyoto Protocol according to fundamental standards of fairness and justice, was demonstrated. Based on calculations of various countries' cumulative emissions per capita, estimates of their cumulative emissions from 1900 to 2005, and their annual emissions allowances into the future (2006―2050), a 470 ppmv atmospheric CO2 concentration target was set. According to the following four objective indicators―total emissions allowance from 1900 to 2050, actual emissions from 1900 to 2005, emissions levels in 2005, and the average growth rate of emissions from 1996 to 2005―all countries and regions whose population was more than 300000 in 2005 were divided into four main groups: countries with emissions deficits, countries and regions needing to reduce their gross emissions, countries and regions needing to reduce their emissions growth rates, and countries that can maintain the current emissions growth rates. Based on this proposal, most G8 countries by 2005 had already expended their 2050 emissions allowances. The accu-mulated financial value based on emissions has reached more than 5.5 trillion US dollars (20 dollars per ton of CO2). Even if these countries could achieve their ambitious emissions reduction targets in the future, their per capita emissions from 2006 to 2050 would still be much higher than those of developing countries; under such circumstance, these future emissions would create more than 6.3 trillion US dollars in emissions deficits. Because of their low cumulative emissions per capita, most developing countries fall within one of the latter two groups, which means that they have leeway for making emissions decisions in the future. Although China accounts for more than 30% of the total global emissions allowance from 2006 to 2050, its total emissions can be controlled within that allow-ance by no other way than reducing its future emissions growth rates. In the end, nine key issues related to international climate negotiations were briefly addressed.DING ZhongLi1, DUAN XiaoNan2, GE QuanSheng3 & ZHANG ZhiQiang4 1 Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2 The General Office of Chinese Academy of Sciences, Beijing 100864, China 3 Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 4 The Lanzhou Branch of the National Science Library, the Scientific Information Center for Resources and Environment, Lanzhou 730000, China 2009Science China Earth Sciences2009,52,10:50
13The deformation pattern and fault rate in the Tianshan Mountains inferred from GPS observations显示文摘Based on GPS measurements conducted from 1992 to 2006, we present the current crustal movement velocity field for approximately 400 sites in the Tianshan Mountains and their adjacent areas, and estimate slip rates on the major faults using a 2-D elastic dislocation model. Our studies show slip rates within the range of 1―4 mm/a on the NW-SE trending strike-slip faults (such as Talas-Fergana fault) in the Tianshan Mountains. We also found the slip rates on the approximately WE-SN trending gently-dipping detachment fault vary from 10―13 mm/a for the southwest Tianshan Mountains to 2―5 mm/a for the eastern Tianshan Mountains, and to 6―12 mm/a for the Kyrgrz Tianshan. The GPS velocity field reveals that the total convergence is not uniformly distributed across the Tianshan Mountains, with 80%―90% of the N-S shortening absorbed along the southern and northern edges, and relatively little deformation accommodated within the interior. This first-order feature of strain pattern is explained best by underthrusting of adjacent blocks beneath the Tianshan Mountains along a basal detachment fault. We found the occurrence of historical M7―8 earthquakes somewhere in the locked ramp that connects the creeping and locking segments of the detachment, thereby resulting in elastic strain concentration and accumulation around it. The elastic strain confined in the upper crustal layer above the detachment ultimately releases through infrequent great earthquakes in the Tianshan Mountains, resulting in considerable folding and faulting at their margins. The Tianshan Mountains propagated outward and rose progressively as a wedge-shaped block.YANG ShaoMin1,2, LI Jie1,3 & WANG Qi2,1 1 Research Center of Space Science and Technology, China University of Geosciences, Wuhan 430074, China 2 Institute of Seismology, China Earthquake Administration, Wuhan 430071, China 3 Earthquake Administration of Xinjiang Uygur Autonomous Region, Urumqi 830011, China 2008Science China Earth Sciences2008,51,8:43
14Studies on the integration of hepatitis B virus DNA sequence in human sperm chromosomes显示文摘Aim:To study the integration of hepatitis Bvirus(HBV)DNAinto sperm chromosomes in hepatitsBpatients and the features of its integration.Methods:Sperm chromosomes of 14subjects(5healthy controls and9HBpatients,including1acute hepatitis B,2chronic active hepatitisB,4chronic persistent hepatitsB,2HBsAg chronic carriers with no clinical symptoms)were prepared using imterspecific in vitro fertilization between zona-free hamster oocytes and human spermatozoa.Fluosescence in situ hybridization(FISH)to sperm chromosome spreads was carried out with biotin-labeled full length HBVDNAprobe to detect the specificHBVDNA sequences in the sperm chromosomes.Results:Specific fluorescent signal spots for HBVDNAwere seen iv sperm chromosomes of one patient with chronic persistent hepatitisB.In9(9/42)sperm chromosome complements containing fluorescent signal spots,one presented5obvious FISHspots and the others2to4signals.The fluorescence intensity showed significant difference among the signal spots.The distribution of signal sites among chromosomes seems to be random.Con clusion:HBV could integrate into human sperm chromosomes.Results suggest that the possibility of vertical transmission of HBVvia the germ line tothe next generation is present.Jian-Min HUANG~(1,*), Tian-Hua HUANG~1, Huan-Ying QIU~2, Xiao-Wu FANG~1, Tian-Gang ZHUANG~1, Jie-Wen QIU~3 ~1Department of Cell Biology and Medical Genetics, Shantou University Medical College ~2Shantou University Hospital ~3Department of Infectious Disease of the Second Affiliated Hospital, Shantou University Medical College, Shantou 515031, China 2002Asian Journal of Andrology2002,4,3:49
15Characterization 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
16Petrogenesis and dating of the Kangding complex,Sichuan Province显示文摘An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 721 and 773 Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2468 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.CHEN Yuelong 1 , LUO Zhaohua 1 , ZHAO Junxiang, LI Zhihong, ZHANG Hongfei & SONG Biao 3 1. Faculty of Earth Sciences and Natural Resources, China University of Geosciences, Beijing 100083, China 2. Faculty of Earth Sciences, China University of Geosciences, Wuhan 430074, China 3. Beijing SHRIMP Center, Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2005Science China Earth Sciences2005,48,5:40
17Kinematics and dynamics of the Mesozoic orogeny and late-orogenic extensional collapse in the Sino-Mongolian border areas显示文摘The Sino-Mongolian border areas underwent two important tectonic events during Mesozoic time after late Paleozoic orogeny: a late Triassic to earlier Jurassic contractional event that resulted in a large-scale south-vergent thrust during the orogeny and a late Jurassic-earlier Cretaceous extensional event in a north-south direction that formed a metamorphic core complex. The kinematic and dynamic analyses show that the thrust sheet moved southwards with a kinematic vorticity number of ca. -0.10 and sub-horizontal maximum compressive stress axis that belongs to a contraction-thickening shear. The upper plate of the late-orogenic detachment relatively moved in a 165°direction. The average kinematic vorticity in its earlier stage was 0.74 that belongs to simple shear dominated shearing and related to the maximum compressive stress axes dipping at ~66°, while the later average kinematic vorticity was ~0.55°that belongs to pure shear dominated shearing with sub-vertical maximum compressive stress axes. This suggests that the thrusting led to the crust thickened and the lower plate rocks that were originally located in the upper crust depressed through a brittle-ductile transition zone into the lower crust and became warmer. The heated rocks trended to uplift since their increasing volume and decreasing density while the loading of the upper-plate rocks increased due to the structural thickening. Under the combined effect of the loading and the thermal-uplifting, the ductile shear zone in between increased in its component of vertical pure shear. Once its pure-shear component exceeded its simple-shear one the ductile shear zone became an extension-thinned shear zone. This progressive transitional process reflects internal and essential temporal and spatial relationships: the extensional factor nucleated during the crust thickening by thrusting and increase of the extensional factor finally led to late-orogenic collapse.ZHENG Yadong 1 & WANG Tao2 1. Key Laboratory of Orogenic Belts and Crustal Evolution (Peking University), Ministry of Education, Beijing 100871, China 2. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2005Science China Earth Sciences2005,48,7:38
18Clinical implication of VEGF serum levels in cirrhotic patients with or without portal hypertension显示文摘INTRODUCTIONAngiogenesisorformationofnewbloodvesels,isatightlyregulatedprocesinwhichbloodveselssupplygrowingtisuewithnutrient...Nimer Assy 1,4 , M Paizi 3,4 , D Gaitini 2, Y Baruch 1,4 and G Spira 3,4,5 1999World Journal of Gastroenterology1999,5,4:35
19Mathematical Models for Combined Refraction-Diffraction of Waves on Non-Uniform Current and Depth显示文摘Two mathematical models for combined refraction-diffraction of regular and irregular waves on non-uniform current in water of slowly varying topography are presented in this paper. Model I is derived by wave theory and variational principle separately. It has two kinds of expressions including the dissipation term. Model n is based on the energy conservation equation with energy flux through the wave crest lines in orthogonal curvilinear coordinates and the wave kinematic conservation equation. The analysis and comparison and special cases of these two models are also given.Hong Guangwen Professor, Research Institute of Coastal and Ocean Engineering, Hohai University, 1 Xikang Road, Nanjing 210024 1996China Ocean Engineering1996,11,4:35
20CO_2浓度变化和气候变化对中国陆地生态系统净初级生产及其平衡的影响(英文)显示文摘本文应用陆地生态系统模型(TEM,4.0)对中国陆地生态系统在目前气候下的净初级生产力,以及在CO2浓度增加和气候变化后的净初级生产力的变化进行了预测。气候变化模型采用三种大气环流模型生成,即:GISS、GFDL和OSU模型。在当前气候条件和CO2浓度(312.5×10-6)下,TEM模型预测中国陆地生态净初级生产力为3,653TgC·a-1(1012gC·a-1)。温带常绿阔叶林是生产力最高的生物区,占有中国净初级生产力的最大比例。NPP的空间格局主要与降水量和温度的空间分布相关联。中国陆地生态系统的年净初级生产力对CO2浓度和气候的变化敏感。在陆地区域尺度上,其年净初级生产力仅在CO2浓度上升至519×10-6的情况下可增加6.0%(219TgC·a-1)。在气候变化而无CO2浓度变化的条件下,净初级生产力的响应在GISS气候方案下表现为1.5%(54.8TgC·a-1)的降低,在GFDL-q气候方案下表现为8.4%(306.9TgC·a-1)的增加。在气候和CO2浓度均发生变化的情况下,净初级生产力有较大程度的增加,在GISS气候方案下的增加比例为18.7%(683TgC·a-1),在GFDL-q气候?Xiao 1,2 , X., J.M.Melillo 1, D.W.Kicklighter 1, Y.Pan 1, A.D.McGuire 3 and J.Helfrich 1 ( 1The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA 02543, USA) ( 2 The Joint Program on the Science and Policy of Globa 1998植物生态学报1998,22,2:35
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