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1Climate change tendency and grassland vegetation response during the growth season in Three-River Source Region显示文摘Climate change,climate suitablity change for grassland vegetation,and grassland response to climate change during the growth season are studied systematically by using meteorological data of temperature,precipitation,and length of sunlight from 1961 to 2007,NOAA/AVHRR NDVI from 1982 to 2006,and observations of grass height,biomass,and coverage in enclosed grassland from 1994 to 2006.Two models are developed to evaluate climate change and the climatic suitability of grassland vegetation growth.Average temperature,accumulative precipitation,and length of sunlight during the growth season increased from 1961 to 2007 at rates of 0.24°C/10 yr,2.32 mm/10 yr,and 2.81 h/10 yr,respectively.The increase rates of ave-rage temperature between April and May,and between June and August are 0.17 and 0.30°C/10 yr;accumulative rainfall between April and May increased at a rate of 2.80 mm/10 yr,and accumulative rainfall between June and August decreased at a rate of 0.38 mm/10 yr;the increase rates of accumulative length of sunlight between April and May,and between June and August are 2.15 and 1.2 h/10 yr.The climatic suitability of grassland vegetation growth showed an increasing trend,and the increase rate between April and May is greater than that between June and August.Both NDVI observations from 1982 to 2006 and measurements of grass height,dry biomass,and coverage from 1994 to 2006 show that the climate change has resulted in an increase in plant productivity of the grassland in Three-River Source Region.If some protection measures are taken as soon as possible,the deteriorated grassland in Three-River Source Region can recover.QIAN Shuan1,FU Yang2 & PAN FeiFei3 1 National Meteorological Center,Beijing 100081,China 2 Qinghai Meteorological Research Institute,Xining 810001,China 3 Department of Geography,University of North Texas,Denton,TX 76203,USA 2010Science China Earth Sciences2010,53,10:25
22002—Emergence of the Gas-to-Liquids Industry:a Review of Global GTL Developments显示文摘This paper reviews the status of the gas-to-liquids (GTL) industry - including currentcommercial plants, announced projects and the technologies that are likely to be implemented in thesefuture projects. Today, only 35,000 B/D of GTL products (0.1% of market) are manufactured fromcommercial gas-based plants. Advances in technology have lowered the cost of plants to the point whereGTL plants can be profitable at crude oil prices of $16/B. The advanced stage of development of severalproposed GTL projects and attractive integrated economics, for both the gas field and plant, show thatGTL can be a significant alternative for monetizing natural gas in the 21st century. GTL technologiesincludes more than Fischer-Tropsch technology and extends to other liquid fuels, especially in the oxygenatefamily (methanol, dimethyl ether, etc.).T.H.Fleisch,R.A.Sills,M.D.BriscoeBP Upstream Technology Group, P. O. Box 3092, Houston, TX 77253, USA 2002Journal of Natural Gas Chemistry2002,11,1:22
3Molecular signal transduction in vascular cell apoptosis显示文摘Apoptosis is a form of genetically programmed cell death, which plays a key role in regulation of cellularity in a variety of tissue and cell types including the cardiovascular tissues. Under both physiological and pathophysiological conditions, various biophysiological and biochemical factors, including mechanical forces, reactive oxygen and nitrogen species, cytokines, growth factors, oxidized lipoproteins, etc., ma influence apoptosis of vascular cells. The Fas/Fas ligand/caspase death-signaling pathway, Bcl-2 protein family/mitochondria, the tumor suppressive gene p53, and the proto-oncogene c-myc may be activated in atherosclerotic lesions, and mediates vascular apoptosis during the development of atherosclerosis. Abnormal expression and dysfunction of these apoptosis-regulating genes may attenuate or accelerate vascular cell apoptosis and affect the integrity and stability of atherosclerotic plaques. Clarification of the molecular mechanism that regulates apoptosis may help design a new strategy for treatment of atherosclerosis and ii major complication, the acute vascular syndromes.GENG YONG JIAN Center for Cardiovascular Biology and Atherosclerosis Research, Division of Cardiology, Department of Internal Medicine, University of Texas Houston Health Science Center Medical School, 6431 Fannin Street, MSB 6.045, Houston, TX 77030, USA 2001Cell Research2001,11,4:20
4Discovery of a pterodactylid pterosaur from the Yixian Formation of western Liaoning,China显示文摘A well-preserved pterosaur with nearly complete skull is described from the Lower Cretaceous Yixian Formation at Sihetun in western Liaoning. It is characterized by a low and long crestless skull, slender and pointed teeth, long metacarpal, nearly equal length of metatarsals I -III and short pedal digit V. It is referred to a new genus and species of the family Pterodactylidae: Haopterus gracilis gen. et sp. nov. This is the first pterosaur with a nearly complete skull from the Jehol Biota; it also represents the first non-controversial fossil record of Pterodactylidae in Asia. Haopterus is more derived than Pterodactylus from the Late Jurassic Solnhofen in Germany. This discovery extends the distribution of the family Pterodactylidae from Europe and Africa to Asia and its latest occurrence from the Late Jurassic to the Early Cretaceous. The discovery of Haopterus gracilis provides further evidence for the study of the originand radiation of the Jehol Biota; it also sheds new light on the evolution andWANG Xiaolin & LU Junchang1. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, Beijing 100044, China 2. College of Earth Sciences and Resources, China University of Geo-sciences, Beijing 100083, China 3. Department of Geological Sciences, Southern Methodist University, Dallas, TX 75275, USA 2001Chinese Science Bulletin2001,46,13:17
5Immunization with chlamydial plasmid protein pORF5 DNA vaccine induces protective immunity against genital chlamydial infection in mice显示文摘To validate the immune protective efficacy of pORF5 DNA vaccine and to analyze potential mechanisms related to this protection. In this study, pORF5 DNA vaccine was constructed and evaluated for its protective immunity in a mouse model of genital chlamydial infection. Groups of BALB/c mice were immunized intranasally with pORF5 DNA vaccine. Humoral and cell mediated immune responses were evaluated. The clearance ability of chlamydial challenge from the genital tract and the chlamy- dia-induced upper genital tract gross pathology and histopathological characterization were also de- tected. The results showed that the total and the IgG2a anti-pORF5 antibody levels in serum were sig- nificantly elevated after pcDNA3.1-pORF5 vaccination, as were the total antibody and IgA levels in vaginal fluids. pcDNA3.1-pORF5 induced a significantly high level of Th1 response as measured by robust gamma interferon (IFN-γ). Minimal IL-4 was produced by immune T cells in response to the re-stimulation with pORF5 protein or the inactive elementary body in vitro. pcDNA3.1-pORF5-vacci- nated mice displayed significantly reduced bacterial shedding upon a chlamydial challenge and an accelerated resolution of infection. 100% of pcDNA3.1-pORF5 vaccinated mice successfully resolved the infection by day 24. pcDNA3.1-pORF5-immunized mice also exhibited protection against patho- logical consequences of chlamydial infection. The stimulated index was significantly higher than that of mice immunized with pcDNA3.1 and PBS (P<0.05). Together, these results demonstrated that immu- nization with pORF5 DNA vaccine is a promising approach for eliciting a protective immunity against a genital chlamydial challenge.LI ZhongYu1,2, WANG ShiPing1, Wu YiMou2, ZHONG GuangMing3 & CHEN Ding3 1 Xiangya School of Medicine, Central South University, Changsha 410078, China 2 Department of Microbiology and Immunology, University of South China, Hengyang 421001, China 3 University of Texas Health Science Center at San Antonio, TX 78229, USA 2008Science China(Life Sciences)2008,51,11:16
6Automated detection of lunar craters based on object-oriented approach显示文摘The object-oriented approach is a powerful method in making classification. With the segmentation of images to objects, many features can be calculated based on the objects so that the targets can be distinguished. However, this method has not been applied to lunar study. In this paper we attempt to apply this method to detecting lunar craters with promising results. Craters are the most obvious features on the moon and they are important for lunar geologic study. One of the important questions in lunar research is to estimate lunar surface ages by examination of crater density per unit area. Hence, proper detection of lunar craters is necessary. Manual crater identification is inefficient, and a more efficient and effective method is needed. This paper describes an object-oriented method to detect lunar craters using lunar reflectance images. In the method, many objects were first segmented from the image based on size, shape, color, and the weights to every layer. Then the feature of 'contrast to neighbor objects' was selected to identify craters from the lunar image. In the next step, by merging the adjacent objects belonging to the same class, almost every crater can be taken as an independent object except several very big craters in the study area. To remove the crater rays diagnosed as craters, the feature of 'length/width' was further used with suitable parameters to finish recognizing craters. Finally, the result was exported to ArcGIS for manual modification to those big craters and the number of craters was acquired.YUE ZongYu1,2,3,4, LIU JianZhong3 & WU GanGuo2 1 Institute of Remote Sensing Application, Chinese Academy of Sciences, Beijing 100101, China 2 China University of Geosciences (Beijing), Beijing 100083, China 3 National Astronomical Observatories of Chinese Academy of Sciences, Beijing 100012, China 4 Department of Geological Sciences, The University of Texas at San Antonio, San Antonio, TX 78249, U.S.A 2008Chinese Science Bulletin2008,53,23:12
7Free Radical Generation by Selenium Compounds and Their Prooxidant Toxicity显示文摘Selemum (Se) and many of its compounds are among the most toxic of nutrients. Selenium toxicity was first described in range animals in the western United States in the 1930’s which consumed' selenium accumulator' plants of the genus Astragalus, Xylorrhiza,Oonopsis, and Stanleya. Selenites and selenates from the soil accumulate in these plants primarily as methylated selenium compounds and plants evolve dimethyldiselenide and dimethyselenide.Dietary selenium, primarily as selenomethionine and selenocysteine for humans fulfill the dietary requirement for selenoenzymes and proteins. In humans and animals excessive dietary selenium may be toxic. In vitro, selenium compounds such as selenite, selenium dioxide and diselenides react with thiols, such as glutathione, producing superoxide and other reactive oxygen species. This catalytic reaction of selenium compounds with thiols likely accounts for selenium toxicity to cells ex vivo and in vivo where the major glutathione producing organ,the liver, is also the major target organ of selenium toxicity.Selenium enzymes and selenoethers that do not readily form a selenide (RSe-) anion and compounds such as Ebselen where selenium is sequestered, are not toxic. Methylation of selenium by both plants and animals serves to detoxify selenium by generating methylselenides. Alternatively, full reduction of Se to elemental selenium (Se0) as done by some bacteria and the formation of heavy metal selenides such as Ag2Se or Hg2Se, results in a non-catalytic nontoxic form of selenium.This catalytic prooxidant attribute of some selenium compounds appears to account for its toxicity when such activity exceeds plant and animal methylation reactions and antioxidant defenses. This prooxidant activity may also account for cellular apoptosis and may provide a useful pharmaceutical application for selenium compounds as antibacterial, antiviral, antifungal and anticancerJULIAN E. SPALLHOLZ(Food and Nutrition, Texas Technology University,Lubbock, TX 79404, USA) 1997Biomedical and Environmental Sciences1997,10,2:11
8A Spatially Weighted Degree Model for Network Vulnerability Analysis显示文摘Using degree distribution to assess network vulnerability represents a promising direction of network analysis.However,the traditional degree distribution model is inadequate for analyzing the vulnerability of spatial networks because it does not take into consideration the geographical aspects of spatial networks.This paper proposes a spatially weighted degree model in which both the functional class and the length of network links are considered to be important factors for determining the node degrees of spatial networks.A weight coefficient is used in this new model to account for the contribution of each factor to the node degree.The proposed model is compared with the traditional degree model and an accessibility-based vulnerability model in the vulnerabil-ity analysis of a highway network.Experiment results indicate that,although node degrees of spatial networks derived from the tra-ditional degree model follow a random distribution,node degrees determined by the spatially weighted model exhibit a scale-free distribution,which is a common characteristic of robust networks.Compared to the accessibility-based model,the proposed model has similar performance in identifying critical nodes but with higher computational efficiency and better ability to reveal the overall vulnerability of a spatial network.WAN Neng1,ZHAN F.Benjamin1,2,CAI Zhongliang2 1.School Texas Center for Geographic Information Science,Department of Geography,Texas State University,San Marcos,TX 78666,USA 2.School of Resource and Environmental Science,Wuhan University,129 Luoyu Road,Wuhan 430079,China 2011Geo-Spatial Information Science2011,14,4:9
912-Deoxyphorbol Esters from Euphorbia Fischeriana显示文摘12-DeoxyphorbolEstersfromEuphorbiaFischerianaWenZiLIU;XiaoYunWU;GenJinYANG;QingGaoMA;TianXiZHOU;XiCanTANGandGuoWeiQIN(Departm...Liu, WZ Wu, XY Yang, GJ Ma, QG Zhou, TX Tang, XC Qin, GW 1996Chinese Chemical Letters1996,7,10:7
10Recent Advances in Swine Amino Acid Nutrition显示文摘Recent advances in swine protein nutrition are characterized by the development of functional amino acids(AA)in regulating fetal and postnatal survival,growth and development.These AA include arginine,glutamine,glutamate,proline,leucine,cysteine and tryptophan.Due to limited knowledge on AA nutrition,pork producers have traditionally paid little attention to supplementing the arginine family of AA to swine diets.Results of recent studies indicate that functional AA serve important regulatory functions in nutrient metabolism,protein turnover,and immune function,therefore enhancing efficiency of feed utilization by pigs.The underlying mechanisms include activation of nitric oxide,mammalian target of rapamycin,gaseous signaling,and AMP-activated protein kinase pathways,as well as anti-oxidative function.Dietary supplementation with arginine,glutamine,proline or leucine to weanling piglets enhances their growth performance.Arginine or glutamine is also effective in increasing milk production by lactating sows.Furthermore,supplementing arginine to the diet of pregnant gilts between days 30 and 114 of gestation increases the number of live-born piglets and litter birth-weight.Availability of feed-grade functional AA holds great promise for improving animal health and nutrient utilization in pig production worldwide.Additionally,feedstuffs of animal origin [e.g.,blood meal(ring dried),feather meal(hydrolyzed),meat and bone meal,porcine protein meal,and poultry by-product meal(both feed-and petfood-grades)] are excellent and cost-effective sources of both essential and functional AA for formulating balanced swine diets.New knowledge on AA nutrition provides a much needed scientific basis for revising the next edition of swine nutrient requirements.Guoyao Wu Department of Animal Science and Faculty of Nutrition,Texas A&M University,College Station,TX,77843,U.S.A and State Key Laboratory of Animal Nutrition,China Agricultural University,Beijing,100193,China 2010Journal of Animal Science and Biotechnology2010,1,2:7
11The Asymptotic Behavior of a Class of Second Order Differential Equation显示文摘In the paper the asympotic behavior of the solution of the following second order differential equation y+ q(t)f(y) =0 is investigated. Some results for asymptotic behavior of the nonoscillation solution are obtained.FENG Zhao-sheng, WANC Xiao-hui, LI Jin-cheng ( Dept. of Math., Texas A&M University, College Station, TX 77843, USA Dept. of Stat., Texas A&M University, College Station, TX 77843, USA Basic Dep., Tianjin Vocational Tech. & Teaching College, Tianjin 3 2001Journal of Mathematical Research and Exposition2001,21,3:6
12Classification of rational holomorphic maps from B^2 into B^N with degree 2显示文摘Rational proper holomorphic maps from the unit ball in C 2 into the unit ball C N with degree 2 are classified, up to automorphisms of balls.JI ShanYu 1 & ZHANG Yuan 2 1 Department of Mathematics, University of Houston, Houston, TX 77204, USA 2 Department of Mathematics, University of California at San Diego, La Jolla, CA 92093, USA 2009Science China Mathematics2009,52,12:4
13THE BENCHMARK LAND PRICE SYSTEM AND URBANLAND USE EFFICIENCY IN CHINA显示文摘ABSTRACT: China began to introduce market principles and establish price mechanism to better manage land and improve land use efficiency in the late 1980s. Since then, land markets begin to emerge. A benchmark land price system, providing guidelines for land use rights selling and transferring, was established in order to overcome lack of market data and experiences in land transaction. The benchmark prices of land use rights are determined by land use, land use density (floor-land ratio), land grades, land improvement, and tenant resettlement costs. This paper first conducts a formal analysis based on modern urban economic theory. The formal model provides a theoretical foundation in which the benchmark land price system is assessed and evaluated in terms of land use and urban development. The paper then concludes that the benchmark price system has two theoretical problems. One is associated with the fact that floor-land ratio plays an important role in land price determination whereas the theory suggests the other way around. That is, floor-land ratio depends on land prices. The other problem is that the benchmark land price system does not provide adequate room for the substitution between land and capital inputs. The substitution is a key in achieving land use efficiency in land markets and urban development process. It is concluded that the practice of the benchmark land price system is at odd with reforms that aim to introduce market principles and mechanism to guide resource uses. Therefore, it is recommended that further land policy reform should be taken.DING Cheng-ri(Department of Landscape Architecture and Urban Planning, Texas A &M University, Mail Stop 3137College Station, TX, 77843, USA) 2001Chinese Geographical Science2001,11,4:4
14Rational holomorphic maps from B^2 into B^N with degree 2显示文摘Rational proper holomorphic maps from the unit ball in C2 into the unit ball CN with degree 2 are studied. Any such map must be equivalent to one of the four types of maps.CHEN Zhihua, Jl Shanyu & XU Dekang Department of Mathematics, Tongji University, Shanghai 200092, China Department of Mathematics, University of Houston, Houston, TX 77204, USA 2006Science China Mathematics2006,49,11:3
15巨噬细胞中缺氧诱导因子1α表达促进动脉粥样硬化的发展显示文摘粥样硬化病变包含缺氧区域,但缺氧病理生理的重要性未知。缺氧诱导因子1a(hypoxia-induciblefactor-1α,HIF-1α)是细胞对低氧反应的关键转录因子。研究人员对HIF-1α在巨噬细胞促进小鼠动脉粥样硬化的生物学效应方面进行调查和验证。刘莉 叶鹏 Aarup A Pedersen TX Junker N Christoffersen C Bartels ED Madsen M Nielsen CH Nielsen LB 2016中华高血压杂志2016,24,9:3
16CONVERGENCE OF CASCADE ALGORITHMS AND SMOOTHNESS OF REFINABLE DISTRIBUTIONS显示文摘In this paper, the author at first develops a method to study convergence of the cascadealgorithm in a Banach space without stable assumption on the initial (see Theorem 2.1), andthen applies the previous result on the convergence to characterizing compactly supportedrefinable distributions in fractional Sobolev spaces and Holder continuous spaces (see Theorems3.1, 3.3, and 3.4). Finally the author applies the above characterization to choosing appropriateinitial to guarantee the convergence of the cascade algorithm (see Theorem 4.2).SUN QIYU Department of Mathematics, University of Houston, Houston, TX 77204, USA. Department of Mathematics, National University of Singapore, 10 Kent Ridge Crescent, 119260, Singapore. 2003Chinese Annals of Mathematics,Series B2003,24,3:3
17CARMA3: A novel scaffold protein in regulation of NF-κB activation and diseases显示文摘CARD recruited membrane associated protein 3 (CARMA3) is a novel scaffold protein. It belongs to the CARMA protein family, and is known to activate nuclear factor (NF)- κB. However, it is still unknown which receptor functions upstream of CARMA3 to trigger NF-κB activation. Recently, several studies have demonstrated that CARMA3 serves as an indispensable adaptor protein in NF-κB signaling under some G protein-coupled receptors (GP- CRs), such as lysophosphatidic acid (LPA) receptor and angiotensin (Ang) Ⅱ receptor. Mechanistically, CARMA3 recruits its essential downstream molecules Bcl10 and MALT1 to form the CBM (CARMA3-Bcl10-MALT1) signalosome whereby it triggers NF-κB activation. GPCRs and NF-κB play pivotal roles in the regulation of various cellular functions, therefore, aberrant regulation of the GPCR/NF-κB signaling axis leads to the development of many types of diseases, such as cancer and atherogenesis. Recently, the GPCR/CARMA3/NF-κB signaling axis has been confirmed in these specific diseases and it plays crucial roles in the pathogenesis of disease progression. In ovarian cancer cell lines, knockdown of CARMA3 abolishes LPA receptor-induced NF-κB activation, and reduces LPA-induced ovarian cancer invasion. In vascular smooth cells, downregulation of CARMA3 substantially impairs Ang-Ⅱ-receptor-induced NF-κB activation, and in vivo studies have confirmed that Bcl10- deficient mice are protected from developing Ang-Ⅱ-receptor-induced atherosclerosis and aortic aneurysms. In this review, we summarize the biology of CARMA3, describe the role of the GPCR/CARMA3/NF-κB signaling axis in ovarian cancer and atherogenesis, and speculate about the potential roles of this signaling axis in other types of cancer and diseases. With a significant increase in the identification of LPA- and Ang-Ⅱ-like ligands, such as endothelin-1, which also activates NF-κB via CARMA3 and contributes to the development of many diseases, CARMA3 is emerging as a novel therapeutic target for various types of cancer and other diseases.Jiyuan Sun, Department of Neuro-Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, TX 77030, United States 2010World Journal of Biological Chemistry2010,1,12:2
18Outsmarting cancer:an international brainstorm in Guangzhou显示文摘Cancer is the most deadly disease in the United States.In developing countries such as China, cancer is increasingly prevalent as a cause of death.The “war against cancer” that was initially declared in the United States has become a global war that requires an alliance of world-wide cancer researchers.As part of such an effort, the Second Guangzhou International Symposium on Oncology was held on May 20-22, 2011, in Guangzhou, China.Chao-Nan Qian 1,2 and Wei Zhang 31 Laboratory of Cancer and Developmental Cell Biology,Van Andel Research Institute,Grand Rapids,MI 49503,USA 2 State Key Laboratory of Oncology in South China,Sun Yat-sen University Cancer Center,Guangzhou,Guangdong 510060,P.R.China 3 Department of Pathology,University of Texas MD Anderson Cancer Center,Huston,TX 77030,USA. 2011Chinese Journal of Cancer2011,30,8:2
19Antioxidant activities of Salvia miltiontaiza and Panax notoginseng显示文摘Zhan GR Xiang ZJ Ye TX 2006Food Chem2006,99,4:1
20Stat3 activation regulates the expression of matrix metalloproteinase-2 and tumor invasion and metastasis 显示文摘Xie TX Wei D Liu M 2004Oncogene2004,23,20:1
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