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| 1 | Further support for a Cretaceous age for the feathered-dinosaur beds of Liaoning,China:New ^(40)Ar/^(39)Ar dating of the Yixian and Tuchengzi Formations显示文摘We report new 40Ar/39Ar dating results ob-tained from total fusion and incremental-heating analyses of sanidine and biotite from three tuffs found interbedded within the fossil-bearing deposits of Liaoning, northeast China. The first is a new sample of the Bed 6 Sihetun tuff from the Yixian Formation, previously dated by our team as middle Early Cretaceous, and recently considered by Lo et al., partially reset due to metamorphism from a nearby ba-saltic sill. The second is the Yixian Bed 9 tuff from Heng-daozi considered by Lo et al. to be unaffected by metamor-phism and whose age, based on total fusion 40Ar/39Ar dating of biotite, argues for a Jurassic age for the Yixian Formation. The third tuff is a previously undated tuff from the upper part of the underlying Tuchengzi Formation. Single crystal total fusion 40Ar/39Ar analyses of the Sihetun sanidine showed homogeneous radiogenic Ar, Ca/K ratios, excellent reproducibility and gave a mean age of 125.0 ± 0.18 (1SD) ± 0.04 (SE) Ma. Single sanidine | C. C. Swisher III, WANG Xiaolin, ZHOU Zhonghe, WANG Yuanqing, JIN Fan, ZHANG Jiangyong , XU Xing, ZHANG Fucheng & WANG YuanDepartment of Geological Sciences, Wright Labs, Rutgers University, Piscataway, New Jersey 08854, USA (e-mail: cswish@rutgers. rci.e | 2002 | Chinese Science Bulletin2002，47，2： | 83 |
| 2 | L^p-Boundedness of Marcinkiewicz Integrals with Hardy Space Function Kernels | Yong Ding Department of Mathematics, Beijing Normal University, Beijing 100875, P. R. China Dashan Fan Department of Mathematics, Anhui University and University of Wisconsin-Milwaukee. MW 53201 USA Yibiao Pan Department of Mathematics, University of Pittsburgh. Pittsburgh. Pennsylvania 15260. USA | 2000 | Acta Mathematica Sinica,English Series2000，16，4： | 88 |
| 3 | Constructions: A new theoretical approach to language显示文摘A new theoretical approach to language has emerged in the past 10-15 years that allows linguistic observations about form-meaning pairings constructions — to be stated directly. Constructionist approaches aim to account for the full range of facts about language, without assuming that a particular subset of the data is part of a privileged 揷ore? Researchers argue that unusual constructions shed light on more general issues, and serve to illuminate what is required for a complete account of language. | Adele E. Goldberg (Linguistics Department, University of Illinois, Urbana, IL 61801-0168, USA) | 2003 | 外国语2003，26，3： | 165 |
| 4 | Effect of phosphorylation of MAPK and Stat3 and expression of c-fos and c-jun proteins on hepatocarcinogenesis and their clinical significance显示文摘AIM To study the effect of phosphorylation ofMAPK and Stat3 and the expression of c-fos andc-jun proteins on hepatocellular carcinogenesisand their clinical significance.METHODS SP immunohistochemistry was usedto detect the expression of p42/44MAPK, p-Stat3,c-fos and c-jun proteins in 55 hepatocellularcarcinomas (HCC) and their surrounding livertissues.RESULTS The positive rates and expressionlevels of p42/44MAPK, p-Stat3, c-fos and c-junproteins in HCCs were significantly higher thanthose in pericarcinomatous liver tissues (PCLT).A positive correlation was observed between theexpression of p42/44MAPK and c-fos proteins, andbetween p-Stat3 and c-jun, but there was nosignificant correlation between p42/44MAPK and p-Stat3 in HCCs and their surrounding livertissues.CONCLUSION The abnormalities of Ras/Rat/MAPK and JAKs/ Stat3 cascade reaction maycontribute to malignant transformation ofhepatocytes. Hepatocytes which are positive forp42/ 44MAPK, c-fos or c-jun proteins may bepotential malignant pre-cancerous cells.Activation of MAPK and Stat3 proteins may be anearly event in hepatocellular carcinogenesis. | De Yun Feng Hui Zheng Yi Tan Rui Xue Cheng Department of Pathology, Hunan Medical University, Changsha 410078, Hunan Province, China New England Biolab, MA, USA | 2001 | World Journal of Gastroenterology2001，7，1： | 75 |
| 5 | Vegetation and soil carbon storage in China显示文摘This study estimated the current vegetation and soil carbon storage in China using a biogeochemical model driven with climate, soil and vegetation data at 0.5°latitude-longitude grid spatial resolution. The results indicate that the total carbon storage in China's vegetation and soils was 13.33 Gt C and 82.65 Gt C respectively, about 3% and 4% of the global total. The nationally mean vegetation and soil carbon densities were 1.47 kg C/m2 and 9.17 kg C/m2, respectively, differing greatly in various regions affected by climate, vegetation, and soil types. They were generally higher in the warm and wet Southeast China and Southwest China than in the arid Northwest China; whereas vegetation carbon density was the highest in the warm Southeast China and Southwest China, soil carbon density was the highest in the cold Northeast China and southeastern fringe of the Qinghai-Tibetan Plateau. These spatial patterns are clearly correlated with variations in the climate that regulates plant growth and soil organic matter decomposition, and show that vegetation and soil carbon densities are controlled by different climatic factors. | LI Kerang, WANG Shaoqiang & CAO MingkuiInstitute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China Department of Geography, Maryland University, College Park,MD 20742, USA Correspondence should be addressed to Li Kerang | 2004 | Science China Earth Sciences2004，47，1： | 60 |
| 6 | 华北燕山带:构造、埃达克质岩浆活动与地壳演化(英文)显示文摘埃达克质火成岩在中国东部,包括燕山带是很常见的,一般认为它们是下地壳不均匀的镁铁质岩石及/或富集的上地幔岩石在高压(≥1.5 GPa)下部分熔融的结果。在燕山带内埃达克岩浆的形成有一个很长的时间(约190~80 Ma),然而岩浆活动的峰期却与约170~130 Ma间有基底岩石卷入的陆壳收缩期相一致。尽管埃达克质岩浆活动的历史很长,但那种把岩浆活动与岩石圈的拆沉效应相联系的模式似乎是不适当的。在该带内,埃达克质与非埃达克质岩浆活动有一部分是同时的,而且在地理分布上也是相间的,这说明了在下地壳和上地幔岩石的部分熔融中成分是相当不均匀的。侏罗纪及白垩纪熔融作用的热源应当是与古太平洋板块俯冲相关的中生代板底垫托的玄武岩浆。除了局部例外,在燕山带,埃达克质岩浆活动的终结和碱性岩浆活动的开始约在130~120 Ma,在此时期收缩作用使东亚大达200万km^2以上的地区发生了NW—SE向的区域性伸展作用。强烈的地壳伸展仅局限于华北克拉通北缘分布的少数几个变质核杂岩中。陆壳的伸展减薄合理地解释了130~120 Ma间发生高压埃达克质熔融条件的终结,尽管还有局部年轻的埃达克火山活动(约120~80Ma)可以在伸展规模有限而厚的地壳依然存在的地区继续出现。燕山区早白垩世的碱性侵入体中的锆石不存在前寒武纪? | Gregory A. DAVIS Department of Earth Sciences, University6 of Southern California, Los Angeles,California 90089-0740 USA Department of Geology , China University of Geosciences , Beijing 100083, China | 2003 | 地学前缘2003，10，4： | 46 |
| 7 | Belowground carbon balance and carbon accumulation rate in the successional series of monsoon evergreen broad-leaved forest显示文摘The balance, accumulation rate and temporal dynamics of belowground carbon in the successional series of monsoon evergreen broadleaved forest are obtained in this paper, based on long-term observations to the soil organic matter, input and standing biomass of litter and coarse woody debris, and dissolved organic carbon carried in the hydrological process of subtropical climax forest ecosystem—monsoon evergreen broad-leaved forest, and its two successional forests of natural restoration—coniferous and broad-leaved mixed forest and Pinus massoniana forest, as well as data of root biomass obtained once every five years and respiration measurement of soil, litter and coarse woody debris respiration for 1 year. The major results include: the belowground carbon pools of monsoon evergreen broad-leaved forest, coniferous and broad-leaved mixed forest, and Pinus massoniana forest are 23191 ± 2538 g·m?2, 16889 ± 1936 g·m?2 and 12680 ± 1854 g·m?2, respec- tively, in 2002. Mean annual carbon accumulation rates of the three forest types during the 24a from 1978 to 2002 are 383 ± 97 g·m?2·a?1, 193 ± 85 g·m?2·a?1 and 213 ± 86 g·m?2·a?1, respectively. The belowground carbon pools in the three forest types keep increasing during the observation period, suggesting that belowground carbon pools are carbon sinks to the atmosphere. There are seasonal variations, namely, they are strong carbon sources from April to June, weak carbon sources from July to September; while they are strong carbon sinks from October to November, weak carbon sinks from December to March. | ZHOU Guoyi1, ZHOU Cunyu1, LIU Shuguang2, TANG Xuli1, OUYANG Xuejun1, ZHANG Deqiang1, LIU Shizhong1, LIU Juxiu1, YAN Junhua1, ZHOU Chuanyan1, LUO Yan1, GUAN Lili1 & LIU Yan1 1. Dinghushan Forest Ecosystem Research Station, Chinese Academy of Sciences, Guangzhou 510650, China 2. SAIC, EROS Data Center, U.S. Geological Survey, Sioux Falls, SD 57198, USA | 2006 | Science China Earth Sciences2006，49，3： | 36 |
| 8 | Estimation of internal nutrient release in large shallow Lake Taihu, China显示文摘Based on field investigation of wave, sediment suspension and the changes in nutrient concentration of the water column in Lake Taihu, China, we proposed two release models to quantify nutrient release under static and dynamic conditions, respectively. Under static conditions, nutrient release from sediments to the overlying water mainly depends on chemical diffusion induced by concentration gradient, in which the nutrient release is controlled by the temperature, dissolved oxygen concentration in the sediment-water interface, oxidation-reduction potential and the concentration difference between porewater and overlying water. Under dynamic condition (or disturbed condition),both dissolved and particulate nutrients in sediments are released into the water column because of wind-induced sediment suspension. The amount of nutrient release under dynamic conditions is larger than that under the static condition. The release of dissolved nutrients, however, does not increase because the wind induced turbulence made oxidation of metallic elements such as Fe (ferric iron), Mn which are capable of precipitating soluble reactive phosphate (SRP). Under dynamic conditions, therefore, the release of total phosphorus (TP) increases dramatically but the release of SRP is close to those under static conditions. In sediments of Lake Taihu, high Fe content leads to a high ratio of Fe to P contents in sediments (Fe:P ratio). Under dynamic conditions, therefore, nutrient release is controlled by the intensity of disturbance, sediment consolidation and nutrient content in sediments.As for dissolved nutrients, especially SRP, the release is also controlled by the intensity of dynamic re-oxidation, Fe content in sediments and nutrient concentration gradient between porewater and overlying water. Based on these two release modes, the release flux in Lake Taihu has been estimated. In the static condition (i.e. laboratory experimental condition), total release of NH4+-N for whole lake is ca. 10,000 ton/a, and PO43--P is ca. 900 ton/a. In the dynamic condition, nutrient release following sediment suspension was estimated according to three different intensities of wind forcing which were defined as 'calm' (wind speed is less than 2 m/s), 'gentle' (wind speed is greater than 2 m/s and less than 6 m/s) and 'gust' (wind speed is greater than 6 m/s). The release rate in the condition of 'calm' was estimated in terms of the nutrient release in the laboratory experimental static condition; whereas the release rate in conditions of 'gentle' and 'gust' was estimated in terms of measurement during sediment resuspension conducted in flume experiments. With the observation of wind velocity and frequency in 2001, each type of wind forcing took the frequency of 12%, 82% and 6% for 'calm', 'gentle' and 'gust', respectively. The yearly release of nitrogen was 81,000 ton and phosphorus was 21,000 ton, which is about 2-6 folds of annual external loading, respectively. | QIN Boqiang, ZHU Guangwei, ZHANG Lu, LUO Liancong, GAO Guang & GU Binhe Nanjing Institute of Geography & Limnology, Chinese Academy of Sciences, Nanjing 210008, China Everglades Department, South Florida Water Management District, 3301 Gun Club Road, West Palm Beach, FL 33406, USA | 2006 | Science China Earth Sciences2006，49，z1： | 37 |
| 9 | A numerical study of the South China Sea deep circulation and its relation to the Luzon Strait transport显示文摘A fine-resolution MOM code is used to study the South China Sea basin-scale circulation and its relation to the mass transport through the Luzon Strait. The modal domain includes the South China Sea, part of the East China Sea, and part of the Philippine Sea so that the currents in the vicinity of the Luzon Strait are free to evolve. In addition, all channels between the South China ,Sea and the Indonesian seas are closed so that the focus is on the Luzon Strait transport. The model is driven by specified Philippine Sea currents and by surface heat and salt flux conditions. For simplicity, no windstress is applied at the surface.The simulated Luzon Strait transport and the South China Sea circulation feature a sandwich vertical structure from the surface to the bottom. The Philippine Sea water is simulated to enter the South China Sea at the surface and in the deep ocean and is carried to the southern basin by western boundary currents. At the intermediate depth, the net Luzon Strait transport is out of the South China Sea and is fed by a western boundary current flowing to the north at the base of the thermocline. Corresponding to the western boundary currents, the basin circulation of the South China Sea is cyclonic gyres at the surface and in the abyss but an anti-cyclonic gyre at the intermediate depth. The vorticity balance of the gyre circulation is between the vortex stretching and the meridional change of the planetary vorticity.Based on these facts, it is hypothesized that the Luzon Strait transports are determined by the diapycnal mixing inside the entire South China Sea. The South China Sea plays the role of a 'mixing mill' that mixes the surface and deep waters to return them to the Luzon Strait at the intermediate depth. The gyre structures are consistent with the Stommel and Arons theory (1960), which suggests that the mixlng-induced circulation inside the South China Sea should be cyclonic gyres at the surface and at the bottom but an anti-cyclonic gyre at the intermediate depth. The simulated gyre circulation at the intermediate depth has been confirmed by the dynamic height calculation based on the Levitns hydrography data.The sandwich transports in the Luzon Strait are consistent with recent hydrographic, al observations.Model results suggest that the Kuroshio tends to form a loop current in the northeastern South China Sea. The simulated Kuroshio Loop Current is generated by the pressure head at the Pacific side of the Luzon Strait and is enhanced by theβ- plane effects. The β- plane appears to be of paramount importance to the South China Sea circulation and to the Luzon Strait translports. Without theβ-plane, the Luzon Strait transports would be greatly reduced and the South China Sea circulation would be complete-ly different. | Yuan Dongliang1. Goddard Earth Science and Technology Center, University of Maryland, Baltimore County Code 971, Laboratory for Hydrospheric Processes, NASA/Goddard Space Flight Center, Greenbelt, MD 20771, USA | 2002 | Acta Oceanologica Sinica2002，21，2： | 37 |
| 10 | CO_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 |
| 11 | THEORY OF DIELECTRIC ELASTOMERS显示文摘In response to a stimulus,a soft material deforms,and the deformation provides a function.We call such a material a soft active material (SAM).This review focuses on one class of soft active materials: dielectric elastomers.When a membrane of a dielectric elastomer is subject to a voltage through its thickness,the membrane reduces thickness and expands area,possibly straining over 100%.The dielectric elastomers are being developed as transducers for broad applications,including soft robots,adaptive optics,Braille displays,and electric generators.This paper reviews the theory of dielectric elastomers,developed within continuum mechanics and thermodynamics,and motivated by molecular pictures and empirical observations.The the-ory couples large deformation and electric potential,and describes nonlinear and nonequilibrium behavior,such as electromechanical instability and viscoelasticity.The theory enables the finite element method to simulate transducers of realistic configurations,predicts the efficiency of elec-tromechanical energy conversion,and suggests alternative routes to achieve giant voltage-induced deformation.It is hoped that the theory will aid in the creation of materials and devices. | Zhigang Suo (School of Engineering and Applied Sciences,Kavli Institute for Nanobio Science and Technology,Harvard University,Cambridge,MA 02138,USA) | 2010 | Acta Mechanica Solida Sinica2010，23，6： | 37 |
| 12 | Complex role of matrix metalloproteinases in angiogenesis显示文摘Matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMP) play a significant role in regulating angiogenesis, the process of new blood vessel formation. Interstitial collagenase (MMP-1), 72 kDa gelatinase A/type IV collagenase (MMP-2), and 92 kDa gelatinase B/type IV collagenase (MMP-9) dissolve extracellular matrix (ECM) and may initiate and Promote angiogenesis. TIMP-1, TIMP-2, TIMP-3, and possibly,TIMP-4 inhibit neovascularisation. A new paradigm is emerging that matrilysin (MMP-7), MMP-9, and metalloelastase (MMP-12) may block angiogehesis by converting plasndnogen to angiostatin, which is one of the most potent angiogenesis antagonists. MMPs and TIMPs play a complex role in regulating angiogenesis. An understanding of the biochemical and cellular pathways and mechanisms of angiogenesis will provide importal information to allow the control of angiogenesis, e.g. the stimulation of angiogenesis for coronary collateral circulation formation; while the inhibition for treating arthritis and cancer. | SANG QING XIANG AMY(Biochemistry Division, Department of Chemistry, Florida State University, Tallahassee, Florida 32306-4390, USA) | 1998 | Cell Research1998，8，3： | 40 |
| 13 | A meta-analysis of oxidative stress markers in schizophrenia显示文摘Oxidative stress has been identified as a possible element in the neuropathological processes of schizophrenia(SCZ).Alteration of oxidative stress markers has been reported in SCZ studies,but with inconsistent results.To evaluate the risk of oxidative stress to schizophrenia,a meta-analysis was conducted,including five markers of oxidative stress [thiobarbituric reactive substances(TBARS),nitric oxide(NO),catalase(CAT),glutathione peroxidase(GP) and superoxide dismutase(SOD)] in SCZ patients versus healthy controls.This study showed that TBARS and NO significantly increased in SCZ,while SOD activity significantly decreased in the disorganized type of SCZ patients.No significant effect size was found for the activities of GP and CAT in SCZ patients(P>0.05).Egger’s regression test observed no significant publication bias across the oxidative stress markers,but found high heterogeneities in all the 5 markers.The subgroup analysis suggested that the ethnicity,sample size of patients and sample sources may contribute to the heterogeneity of the results for TBARS,NO and SOD.The result further demonstrated the involvement of oxidative stress in the pathophysiology of schizophrenia. | ZHANG Ming1,2,ZHAO ZhongMing3,HE Lin1,2,4 & WAN ChunLing1,2 1 Bio-X Center,Key Laboratory for the Genetics of Developmental and Neuropsychiatric Disorders(Ministry of Education),Shanghai Jiao Tong University,Shanghai 200030,China 2 Institutes for Nutritional Sciences,Shanghai Institute of Biological Sciences,Chinese Academy of Sciences,Shanghai 200031,China 3 Departments of Biomedical Informatics,Psychiatry,and Cancer Biology,Vanderbilt University Medical Center,Nashville,TN 37232,USA 4 Institutes of Biomedical Sciences,Fudan University,Shanghai 200032,China | 2010 | Science China(Life Sciences)2010，53，1： | 32 |
| 14 | Numerical simulation of mechanisms of deformation,failure and energy dissipation in porous rock media subjected to wave stresses显示文摘The pore characteristics,mineral compositions,physical and mechanical properties of the subarkose sandstones were acquired by means of CT scan,X-ray diffraction and physical tests.A few physical models possessing the same pore characteristics and matrix properties but different porosities compared to the natural sandstones were developed.The 3D finite element models of the rock media with varied porosities were established based on the CT image processing of the physical models and the MIMICS software platform.The failure processes of the porous rock media loaded by the split Hopkinson pressure bar(SHPB) were simulated by satisfying the elastic wave propagation theory.The dynamic responses,stress transition,deformation and failure mechanisms of the porous rock media subjected to the wave stresses were analyzed.It is shown that an explicit and quantitative analysis of the stress,strain and deformation and failure mechanisms of porous rocks under the wave stresses can be achieved by using the developed 3D finite element models.With applied wave stresses of certain amplitude and velocity,no evident pore deformation was observed for the rock media with a porosity less than 15%.The deformation is dominantly the combination of microplasticity(shear strain),cracking(tensile strain) of matrix and coalescence of the cracked regions around pores.Shear stresses lead to microplasticity,while tensile stresses result in cracking of the matrix.Cracking and coalescence of the matrix elements in the neighborhood of pores resulted from the high transverse tensile stress or tensile strain which exceeded the threshold values.The simulation results of stress wave propagation,deformation and failure mechanisms and energy dissipation in porous rock media were in good agreement with the physical tests.The present study provides a reference for analyzing the intrinsic mechanisms of the complex dynamic response,stress transit mode,deformation and failure mechanisms and the disaster mechanisms of rock media. | JU Yang1,2,WANG HuiJie1,YANG YongMing1,HU QinAng3 & PENG RuiDong1 1 State Key Laboratory of Coal Resources and Safe Mining,Beijing Key Laboratory of Fracture and Damage Mechanics of Rock and Concrete,China University of Mining and Technology,Beijing 100083,China 2 Department of Mechanical and Manufacturing Engineering,University of Calgary,Calgary,Alberta,T2N 1N4,Canada 3 School of Environment and Civil Engineering,College of Engineering,Oklahoma State University,Stillwater,OK 74078,USA | 2010 | Science China(Technological Sciences)2010，53，4： | 32 |
| 15 | Seasonal water storage change of the Yangtze River basin detected by GRACE显示文摘US-Germany co-sponsered satellite gravimetry mission GRACE (Gravity Recovery And Climate Experiment), launched in March 2002, has been producing monthly time series of Earth gravity models up to degree and order of 120. The GRACE mission consists of two identical satellites flying on an almost polar orbit with an altitude of about 300-500 km and satelite-to-satellite ranging of about 220 km. Thanks to the payloads of space-borne GPS receivers, accelerometers and high-precision K-band satelite-to-satellite ranging mesurements, GRACE gravity models are expected to achieve more than one order of magnitude of improvement over previous models at spatial scales of a few hundred kilometers or larger. Recovery of surface mass re-distribution based on GRACE’s time-varying gravity models is applied to studies in solid Earth geophysics, oceanography, climatology and geodesy. At secular time scales, GRACE is expected to provide valuable information on global ice changes, whose variations have profound influences on global climate, and in particular, on sea level changes. At seasonal time scales, GRACE is expected to reveal surface water changes with an ac- curacy of less than 1 cm, or ocean bottom pressure changes with an accuracy of less than 1 mbar (1 mbar =102 Pa). These surface mass redistribution measurements would impove our understanding of the global and regional mass and energy cycles that are critical to human life. Using 15 GRACE monthly gravity models covering the period from April 2002 to December 2003, this study compares seasonal water storage changes recovered from GRACE data and hydrology models at global and regional scales, with particular focus on the Yangtze River basin of China. Annual amplitude of 3.4 cm of equivalent water height change is found for the Yangtze River basin with maximum in Spring and Autumn, agreeing with two state-of-the-art hydrology models. The differences between GRACE re- sults and model predictions are less than 1-2 cm. We conclude that satellite gravimetry has huge potentials in monitering water storage changes in large river basins such as Yangtze. | HU Xiaogong1, CHEN Jianli1,2, ZHOU Yonghong1, HUANG Cheng1 & LIAO Xinhao1 1. Center for Astro-geodynamics Research, Shanghai Astronomical Observatory, National Astronomical Observatories, Shanghai 200030, China 2. Center for Space Research, University of Texas at Austin, 3925 W. Braker Lane, Suite 200, Austin, TX78750, USA | 2006 | Science China Earth Sciences2006，49，5： | 29 |
| 16 | The characteristics of CO_2 assimilation of photosynthesis and chlorophyll fluorescence in transgenic PEPC rice显示文摘With PEPC, PPDK, NADP-ME and PEPC+ PPDK transgenic and untransformed rice (Orysa sativa L.), the activities of related C4 photosynthesis enzymes, the chlorophyll fluorescence parameters, CO2 exchange and other physiological indexes were compared, in which the physiological characteristics of PEPC transgenic rice were mainly studied. The results were as follows: (i) The activities of PEPC in PEPC transgenic rice were 20-fold higher than those in untransformed rice; the light-saturation photosynthetic rates and the carboxylation efficiency of PEPC transgenic rice were increased by 55% and 50% more than those of untransformed rice, respectively, while the CO2 compensation point decreased by 27%. (ii) The PS II photochemical efficiency (Fv/Fm) and photochemical quenching (qp) of transgenic PEPC rice decreased less in comparison with those of untransformed rice after the treatment with high light intensity (3 h) or methyl viologen (MV), a photooxidative reagent, which demonstrated that the tolerance of PEPC | JIAO Demao, LI Xia, HUANG Xueqing, CHI Wei, KUANG Tingyun & Ku SB Maurice1. Institute of Agrobiological Genetics and Physiology, Jiangsu Academy of Agricultural Sciences, Nangjing 210014, China 2. Institute of Botany, the Chinese Academy of Sciences, Beijing 100093, China 3. Botany Department, Washington State University, Pullman, WA 99164-4236, USA | 2001 | Chinese Science Bulletin2001，46，13： | 29 |
| 17 | Roles of Fas signaling pathway in vitamin E succinateinduced apoptosis in human gastric cancer SGC-7901 cells显示文摘AIM: To investigate the roles of Fas signaling pathway in vitamin E succinate-induced apoptosis in human gastric cancer SGC-7901 cells.METHODS: Human gastric cancer SGC-7901 cells were treated with VES at 5, 10, 20 mg@L-1, succinic acid and vitamin E as vehicle control and condition media only as untreated (UT) control. Apoptotic morphology was observed by DAPI staining. Western blot analysis was applied to measure the expression of Fas, FADD and caspase-8 proteins. After the cells were transiently transfected with Fas and FADD antisense oligonucleotides, respectively, caspase-8 activity was determined by flurometric method.RESULTS: The morphologically apoptotic changes were observed after VES treatment by DAPI staining. 23.7 % and 89.6 % apoptosis occurred after 24 h and 48 h of 20 mg@L-1 VES treatment, respectively. The protein levels of Fas, FADD and caspase-8 were evidently increased in a dose-dependent manner after 24 h of VES treatment. The blockage of Fas by transfection with Fas antisense oligonucleotides obviously inhibited the expression of FADD protein. After SGC-7901 cells were transfected with Fas and FADD antisense oligonucleotides, caspase-8 activity was obviously decreased (P<0.01), whereas Fas blocked more than FADD.CONCLUSION: VES-induced apoptosis in human gastric cancer SGC-7901 cells involves Fas signaling pathway including the interaction of Fas, FADD and caspase-8. | Kun Wu Yao Li Yan Zhao Yu-Juan Shah Wei Xia Lan Zhao,Department of Nutrition and Food Hygiene,Public Health School,Harbin Medical University,Harbin 150001,Heilongjiang Province,China Wei-Ping Yu,Genetics Institute,Texas University of USA,Austin,USA | 2002 | World Journal of Gastroenterology2002，8，6： | 30 |
| 18 | A SELF-ADAPTIVE TRUST REGION ALGORITHM显示文摘In this paper we propose a self-adaptive trust region algorithm.The trust region radius is updated at a varable rate according to the ratio between the actual reduction and the predicted reduction of the objective function,rather than by simply enlarging or reducing the original trust region radius at a constant rate.We show that this new algorithm preserves the strong convergence property of traditional trust region methods.Numerical results are also presented. | Long Hei (Institute of Computational Mathematics and Scientific/Engineering Computing, Academy ofMathematics and Systems Sciences, Chinese Academy of Sciences, Beijing 100080, China)(Department of Industrial Engineering and Management Sciences Northwestern University C2SO,2145 Sheridan Road Evanston, Illinois 60208, USA) | 2003 | Journal of Computational Mathematics2003，21，2： | 29 |
| 19 | Epigenetic regulation: methylation of histone and non-histone proteins显示文摘Histone methylation is believed to play important roles in epigenetic memory in various biological processes. However, questions like whether the methylation marks themselves are faithfully transmit- ted into daughter cells and through what mechanisms are currently under active investigation. Previ- ously, methylation was considered to be irreversible, but the recent discovery of histone lysine de- methylases revealed a dynamic nature of histone methylation regulation on four of the main sites of methylation on histone H3 and H4 tails (H3K4, H3K9, H3K27 and H3K36). Even so, it is still unclear whether demethylases specific for the remaining two sites, H3K79 and H4K20, exist. Furthermore, be- sides histone proteins, the lysine methylation and demethylation also occur on non-histone proteins, which are probably subjected to similar regulation as histones. This review discusses recent pro- gresses in protein lysine methylation regulation focusing on the above topics, while referring readers to a number of recent reviews for the biochemistry and biology of these enzymes. | LAN Fei1 & SHI Yang 2 1 Department of Biology, Constellation Pharmaceuticals, 148 Sidney Street, Cambridge, MA 02139, USA 2 Department of Pathology, Harvard Medical School, 77 Ave Louise Pasteur, Boston MA, 02115, USA | 2009 | Science China(Life Sciences)2009，52，4： | 27 |
| 20 | Map and analysis of microsatellites in the genome of Populus: The first sequenced perennial plant显示文摘Environmental Sciences Division, Oak Ridge National Laboratory, TN, USA We mapped and analyzed the microsatellites throughout 284295605 base pairs of the unambiguously assembled sequence scaffolds along 19 chromosomes of the haploid poplar genome. Totally, we found 150985 SSRs with repeat unit lengths between 2 and 5 bp. The established microsatellite physical map demonstrated tr at SSRs were distributed relatively evenly across the genome of Populus. On average, These SSRs occurred every 1883 bp within the poplar genome and the SSR densities in intergenic regions, introns, exons and UTRs were 85.4%, 10.7%, 2.7% and 1.2%, respectively. We took di-, tri-, tetra-and pentamers as the four classes of repeat units and found that the density of each class of SSRs decreased with the repeat unit lengths except for the tetranucleotide repeats. It was noteworthy that the length diversification of microsatellite sequences was negatively correlated with their repeat unit length and the SSRs with shorter repeat units gained repeats faster than the SSRs with longer repeat units. We also found that the GC content of poplar sequence significantly correlated with densities of SSRs with uneven repeat unit lengths (tri-and penta-), but had no significant correlation with densities of SSRs with even repeat unit lengths (di-and tetra-). In poplar genome, there were evidences that the occurrence of different microsatellites was under selection and the GC content in SSR sequences was found to significantly relate to the functional importance of microsatellites. | LI ShuXian & YIN TongMing College of Environment and Forest Resources, Nanjing Forestry University, Nanjing 210037, China Environmental Sciences Division, Oak Ridge National Laboratory, TN, USA | 2007 | Science China(Life Sciences)2007，50，5： | 25 |
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