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    题名 作者 年代 出处 被引量
1Invasive mechanism and control strategy of Ageratina adenophora (Sprengel)显示文摘In order to ascertain the invasive mechanism and control strategy of the invasive Crofton weed, Ageratina adenophora, its ecological adaptability and population differentiation,the formation of single dominant population, displacement of native plants and sustainable management strategies were investigated. The present results helped to clarify and explain such issues as the adaptability post invasion,interaction and competition between inter-and intra-species and community resistance, thereby providing important references to researches on other invasive alien species.WAN FangHao1, LIU WanXue1, GUO JianYing1, QIANG Sheng2, LI BaoPing2, WANG JinJun3, YANG GuoQing1, NIU HongBang1, GUI FuRong1, HUANG WenKun1, JIANG ZhiLin1 & WANG WenQi3 1State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing 100193, China 2College of Plant Protection, Nanjing Agricultural University, Nanjing 210095, China 3Key Laboratory of Entomology and Pest Control Engineering, College of Plant Protection, Southwest University, Chongqing 400716, China 2010Science China(Life Sciences)2010,53,11:42
2Origin of ore-forming fluid in the Piaotang tungsten deposit in Jiangxi Province:Evidence from helium and argon isotopes显示文摘The Piaotang tungsten deposit in Jiangxi Province is one of the most important tungsten deposits in the South China Tungsten Metallogenic Province.In this study,we selected wolframite and chalcopyrite from the main mineralizing stage of the Piaotang tungsten deposit,and analyzed the helium and argon isotopic compositions in fluid inclusions of these minerals.The results show a 3He/4He ratio of 0.17 to 0.86 R/Ra,which fall within the range between continental crust(0.01―0.05 R/Ra) and air-saturated water(1 R/Ra) ,but are significantly lower than those of the normal mantle(6―9 R/Ra) .Their 40 Ar/36 Ar ratios are between 354.5 and 590.7,which are slightly higher than the air-saturated water(295.5) .Along with the other geochemical observation such as the lithium enrichments in the ore bodies and the ore-related granites,we suggest that the ore-forming fluid in the Piaotang tungsten deposit was mainly derived from crustal fluid.It may have mixed with some amounts of air-saturated water,but there was no considerable involvement of mantle-derived fluid.WANG XuDong 1,2,3,NI Pei 1,2,3,JIANG ShaoYong 1,3,ZHAO KuiDong 1,3 & WANG TianGang 1,2,3 1State Key Laboratory for Mineral Deposits Research,Nanjing University,Nanjing 210093,China 2Institute of Geo-Fluids,Nanjing University,Nanjing 210093,China 3 School of Earth Sciences and Engineering,Nanjing University,Nanjing 210093,China 2010Chinese Science Bulletin2010,55,7:26
3DNA barcoding:species delimitation in tree peonies显示文摘Delimitations of species are crucial for correct and precise identification of taxa.Unfortunately 'spe-cies' is more a subjective than an objective concept in taxonomic practice due to difficulties in revealing patterns of infra-or inter-specific variations.Molecular phylogenetic studies at the population level solve this problem and lay a sound foundation for DNA barcoding.In this paper we exemplify the necessity of adopting a phylogenetic concept of species in DNA barcoding for tree peonies(Paeonia sect.Moutan).We used 40 samples representing all known populations of rare and endangered species and several populations of widely distributed tree peonies.All currently recognized species and major variants have been included in this study.Four chloroplast gene fragments,i.e.ndhF,rps16-trnQ,trnL-F and trnS-G(a total of 5040 characters,96 variable and 69 parsimony-informative characters) and one variable and single-copy nuclear GPAT gene fragment(2093?2197 bp,279 variable and 148 parsi-mony-informative characters) were used to construct phylogenetic relationships among the taxa.The evolutionary lineages revealed by the nuclear gene and the chloroplast genes are inconsistent with the current circumscriptions of P.decomposita,P.jishanensis,P.qiui,and P.rockii based on morphology.The inconsistencies come from(1) significant chloroplast gene divergence but little nuclear GPAT gene divergence among population systems of P.decomposita + P.rockii,and(2) well-diverged nuclear GPAT gene but little chloroplast gene divergence between P.jishanensis and P.qiui.The incongruence of the phylogenies based on the chloroplast genes and the nuclear GPAT gene is probably due to the chloro-plast capture event in evolutionary history,as no reproductive barriers exist to prevent inter-specific hybridization.We also evaluated the suitability of these genes for use as DNA barcodes for tree peonies.The variability of chloroplast genes among well-defined species or population systems of a species complex is 4.82 times the figure within the groups,and the GPAT gene is twice as variable between the groups as within the groups.The number of completely divergent sites is sufficient to mark the two subsections,the two species in subsection Delavayanae,and the well-divergent species in subsection Vaginatae.But the genes currently used either from the chloroplast genome or from the nuclear genome alone cannot correctly assign samples of P.decomposita,P.jishanensis,P.qiui,or P.rockii to the spe-cies as currently defined.We conclude that(1) DNA barcoding should be based on prior phylogenetic studies to understand the evolutionary lineages and how well the taxonomic species correspond to the lineages;(2) it is unlikely to find a single short fragment as a barcode for every plant and such a frag-ment could result in misidentification when a chloroplast capture event happened in the evolutionary history of plants like tree peonies;and(3) we suggest striving for a universal marker at the familial level and locally universal barcodes within a family instead of looking for a universal barcode for all plants.ZHANG JinMei1,2,WANG JianXiu1,2,XIA Tao1,2 & ZHOU ShiLiang1 1State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,the Chinese Academy of Sciences,Beijing 100093,China 2Graduate School of the Chinese Academy of Sciences,Beijing 100039,China 2009Science China(Life Sciences)2009,52,6:22
4Third-order point contact approach for five-axis sculptured surface machining using non-ball-end tools(II): Tool positioning strategy显示文摘Based on the mathematical model describing the third-order approximation of the cutter envelope surface according to one given cutter location(CL),a tool positioning strategy is proposed for efficiently machining free-form surfaces with non-ball-end cutters.The optimal CL is obtained by adjusting the inclination and tilt angles of the cutter until its envelope surface and the design surface have the third-order contact at the cutter contact(CC)point,which results in a wide machining strip.The strategy can handle the constraints of machine joint angle limits,global collision avoidance and tool path smoothness in a nature way,and can be applied to general rotary cutters and complex surfaces.Numerical examples demonstrate that the third-order point contact approach can improve the machining strip width greatly as compared with the recently reported second-order one.ZHU LiMin 1 ,DING Han 2 &XIONG YouLun 2 1State Key Laboratory of Mechanical System and Vibration,Shanghai Jiao Tong University,Shanghai 200240,China 2State Key Laboratory of Digital Manufacturing Equipment and Technology,Huazhong University of Science and Technology,Wuhan 430074, China 2010Science China(Technological Sciences)2010,53,8:23
5Estimating forest aboveground biomass using HJ-1 Satellite CCD and ICESat GLAS waveform data显示文摘The ecosystem in northeastern China and the Russian Far East is a hotspot of scientific research into the global carbon balance.Forest aboveground biomass(AGB) is an important component in the land surface carbon cycle.In this study,using forest inventory data and forest distribution data,the AGB was estimated for forest in Daxinganlin in northeastern China by combining charge-coupled device(CCD) data from the Small Satellite for Disaster and Environment Monitoring and Forecast(HJ-1) and Geoscience Laser Altimeter System(GLAS) waveform data from the Ice,Cloud and land Elevation Satellite(ICESat).The forest AGB prediction models were separately developed for different forest types in the research area at GLAS footprint level from GLAS waveform parameters and field survey plot biomass in the Changqing(CQ) Forest Center,which was calculated from forest inventory data.The resulted statistical regression models have a R2=0.68 for conifer and R2=0.71 for broadleaf forests.These models were used to estimate biomass for all GLAS footprints of forest located in the study area.All GLAS footprint biomass coupled with various spectral reflectivity parameters and vegetation indices derived from HJ-1 satellite CCD data were used in multiple regression analyses to establish biomass prediction models(R2=0.55 and R2=0.52 for needle and broadleaf respectively).Then the models were used to produce a forest AGB map for the whole study area using the HJ-1 data.Biomass data obtained from forest inventory data of the Zhuanglin(ZL) Forest Center were used as independent field measurements to validate the AGB estimated from HJ-1 CCD data(R2=0.71).About 80% of biomass samples had an error less than 20 t ha-1,and the mean error of all validation samples is 5.74 t ha-1.The pixel-level biomass map was then stratified into different biomass levels to illustrate the AGB spatial distribution pattern in this area.It was found that HJ-1 wide-swath data and GLAS waveform data can be combined to estimate forest biomass with good precision,and the biomass data can be used as input data for future carbon budget analysis.GUO ZhiFeng1,CHI Hong1,2 & SUN GuoQing1,3 1State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University,Institute of Remote Sensing Applications,Chinese Academy of Sciences,Beijing 100101,China 2Graduate University of Chinese Academy of Sciences,Beijing 100049,China 3Department of Geography University of Maryland,College Park,MD 20742,USA 2010Science China Earth Sciences2010,53,S1:21
6A Genome-wide Functional Characterization of Arabidopsis Regulatory Calcium Sensors in Pollen Tubes显示文摘Calcium, an ubiquitous second messenger, plays an essential and versatile role in cellular signaling. The diverse function of calcium signals is achieved by an excess of calcium sensors. Plants possess large numbers of calcium sensors, most of which have not been functionally characterized. To identify physiologically relevant calcium sensors in a specific cell type, we conducted a genome-wide functional survey in pollen tubes, for which spatiotemporal calcium signals are well-characterized and required for polarized tip growth. Pollen-specific members of calmodulin (CaM), CaM-like (CML), calcium-dependent protein kinase (CDPK) and calcineurin B-like protein (CBL) families were tagged with green fluorescence protein (GFP) and their localization patterns and overexpression phenotypes were characterized in tobacco pollen tubes. We found that several fusion proteins showed distinct overexpression phenotypes and subcellular localization patterns. CDPK24-GFP was localized to the vegetative nucleus and the generative cell/sperms. CDPK32-GFP caused severe growth depolarization. CBL2-GFP and CBL3-GFP exhibited dynamic patterns of subcellular localization, including several endomembrane compartments, the apical plasma membrane (PM), and cytoskeleton-like structures in pollen tubes. Their overexpression also inhibited pollen tube elongation and induced growth depolarization. These putative calcium sensors are excellent candidates for the calcium sensors responsible for the regulation of calcium homeostasis and calciumdependent tip growth and growth oscillation in pollen tubes.Liming Zhou1,2, Ying Fu1,2 and Zhenbiao Yang2,3 (1State Key Laboratory of Plant Physiology and Biochemistry, Department of Plant Sciences, College of Biological Sciences, China Agricultural University, Beijing 100193, China 2China Agricultural University (CAU)-University of California, Riverside (UCR) Joint Center for Biological Sciences and Biotechnology, College of Biological Sciences, China Agricultural University, Beijing 100193, China 3Center for Plant Cell Biology and Department of Botany and Plant Sciences, University of California, Riverside, CA 92521, USA) 2009Journal of Integrative Plant Biology2009,51,8:21
7Full-scale measurements of dynamic response of suspension bridge subjected to environmental loads using GPS technology显示文摘Nowadays, there are many larger and taller engineering structures than in the past. These structures are commonly designed to be more flexible. Thus, they are sensitive to severe wind gust and earthquake tremor. For the dynamic response prediction, finite element (FE) modal updating and structural health monitoring, the dynamic characteristics of a structure are becoming increasingly important. The aim of this paper is to show an emerging tool-the real time kinematic (RTK) global positioning system (GPS), which is used to measure and monitor the low-frequency vibration of Dalian BeiDa Bridge, a medium span suspension bridge. The modal analysis is firstly performed on the developed three-dimensional FE model according to the original blue prints of the bridge to provide the analytical frequencies and mode shapes. The field ambient vibration tests using the accelerometers on the bridge deck are conducted just prior to the use of the GPS system in order to validate the FE model. And then, the calibration test is done to assess the dynamic displacement measurement accuracy of the GPS in three orthogonal directions. The GPS signal properties, such as the amplitude, standard deviations (STD), power spectral density (PSD), and probability density functions (PDF), are studied in details. After that, a structural health monitoring system based on the GPS is devised and installed on the bridge to provide real-time measurement of deck movement. The output-only modal parameter identification is carried out by using the Periodogram method to investigate the responses of the bridge. The result shows that the spectral densities of the displacements measured by the GPS correspond well with the results by the FEM analysis and the accelerometer vibration test. It is concluded that the GPS method is reliable and useful to clarify the ambient vibration response behaviors of the flexible structures. The integration of the GPS and accelerometer methods results in a hybrid arrangement that can help to eliminate some disadvantages of the two devices used separately.YI TingHua1,2, LI HongNan1 & GU Ming2 1State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, Dalian 116024, China 2State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University, Shanghai 200092, China 2010Science China(Technological Sciences)2010,53,2:18
8Formaldehyde stress显示文摘Formaldehyde,one of the most toxic organic compounds,is produced and processed in human cells.The level of human endogenous formaldehyde is maintained at a low concentration(0.01-0.08 mmol L-1 in blood) under physiological conditions,but the concentration increases during ageing(over 65 years old).Clinical trials have shown that urine formaldehyde concentrations are significantly different between elderly Alzheimer's patients(n=91) and normal elderly volunteers(n=38)(P<0.001).Abnormally high levels of intrinsic formaldehyde lead to dysfunction in cognition such as learning decline and memory loss.Excess extracellular and intracellular formaldehyde could induce metabolic response and abnormal modifications of cellular proteins such as hydroxymethylation and hyperphosphorylation,protein misfolding,nuclear translocation and even cell death.This cellular response called formaldehyde stress is dependent upon the concentration of formaldehyde.Chronic impairments of the brain resulted from formaldehyde stress could be one of the mechanisms involved in the process of senile dementia during ageing.HE RongQiao1*,LU Jing1,2 & MIAO JunYe1,2 1State Key Laboratory of Brain and Cognitive Sciences,Institute of Biophysics,Chinese Academy of Sciences,Beijing 100101,China 2Graduate University of Chinese Academy of Sciences,Beijing 100049,China 2010Science China(Life Sciences)2010,53,12:16
9Field experiments on greenhouse gas emissions and nitrogen and phosphorus losses from rice paddy with efficient irrigation and drainage management显示文摘Greenhouse gas emissions,nitrogen and phosphorous losses through ammonia volatilization,leaching and surface drainage from rice paddy under efficient irrigation and drainage were analyzed based on field experimental data in order to reveal the eco-environmental impacts of efficient irrigation and drainage on rice paddy.The results showed that total methane emission from rice paddy under the controlled irrigation was reduced by more than 80% and total nitrous oxide emission increased by 15.9% compared with flooding irrigation.Seasonal comprehensive global warming potentials(GWP) of methane and nitrous oxide were 62.23 gCO2 m-2 for rice paddy under the controlled irrigation,reduced by 68.0% compared with flooding irrigation.Due to large reduction in seepage and surface drainages,nitrogen and phosphorous losses through leaching were reduced by 40.1% and 54.8%,nitrogen and phosphorous losses through surface drainage were reduced by 53.9% and 51.6% from rice paddy under efficient irrigation and drainage compared with traditional irrigation and drainage.Nitrogen loss through ammonia volatilization was reduced by 14.0%.Efficient irrigation and drainage management is helpful to mitigate greenhouse gases emission,nitrogen and phosphorus losses and their pollution on groundwater and surface water.PENG ShiZhang1,2,YANG ShiHong1,2,XU JunZeng1,2 & GAO HuanZhi1,2 1State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China 2College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China 2011Science China(Technological Sciences)2011,54,6:15
10A novel function for the cellulose binding module of cellobiohydrolase I显示文摘A homogeneous cellulose-binding module(CBM)of cellobiohydrolase I(CBHI)from Trichoderma pseudokoningii S-38 was obtained by the limited proteolysis with papain and a series of chromatographs filtration.Analysis of FT-IR spectra demonstrated that the structural changes result from a weakening and splitting of the hydrogen bond network in cellulose by the action of CBMCBHI at 40℃for 24 h.The results of molecular dynamic simulations are consistent with the experimental conclusions, and provide a nanoscopic view of the mechanism that strong and medium H-bonds decreased dramatically when CBM was bound to the cellulose surface.The function of CBMCBHI is not only limited to locating intact CBHI in close proximity with cellulose fibrils,but also is involved in the structural disruption at the fibre surface.The present studies provided considerable evidence for the model of the intramolecular synergy between the catalytic domain and their CBMs.WANG LuShan 1,2 ,ZHANG YuZhong 1 &GAO PeiJi 1 1State Key Laboratory of Microbial Technology,Shandong University,Jinan 250100,China 2Beijing Laboratory of Nanoscale Physics&Devices,Chinese Academy of Sciences,Beijing 100080,China 2008Science China(Life Sciences)2008,51,7:10
11A 'Yellow Cap' on Quaternary Red Clay in Jiujiang,Jiangxi Province显示文摘A thin layer of yellow-brown-colored earth was generally found on Quaternary red clay in Jiujiang,Jiangxi Province. A typical profile was established. Both particle size distribution and REE (rare earthelements) characteristics of the yellow-brown-colored earth of the profile fully suggested its aeolian origin andclose similarity to Naming Xiashu loess. The study also implied aeolian origin of the underlying Quaternaryred clap Compared with the red clay, the yellow- brown- colored earth was less weathered because of its lowercontent of free iron and higher mole ratios of SiO2/A12O3 and SiO2/(Fe2O3+A12O3 ) as well as its lessdeveloped chemical microtextures of quartz grains.In order to study the aged of the two deposits comparatively, the thermoluminescent dating method wasused. As a result, the bottom of the yellow-brown-colored esrth was dated to 6015 ka B. P. and the upperpart of the red clay 38854 ka B. P. It was suggested that the yellow- browm- colored earth was formed inthe Late Pleistocene and was probably the aeolian deposit of the Last Glacial, which corresponded with theMalan loess in the Loess Plateau of the northwestern part of China; while the underlying red clay was formedin the Middle Pleistocene.A 'yellow cap' on Quaternary red clay in Jiujiang implied a great climatic and environmental varistionin the beginning of the Late Pleistocene in the southern pot of China, especially in the middle and lowerreaches of the Yangtze River. The eveal not only halted the rubification, once dominating the region, butalso produced a widespread covering of aeolian deposit, as only occurred in the cold and dry environment.HU XUEFENG GONG ZITONG(1State Key Laboratory of Loess and Quaternary Geology, the Chinese Academy of Sciences, P. O. Box: 17,xi’an 710054 (China))(2Institute of Soil Science, the Chinese Acodemy of Sciences, P. O. Box 821, Nanjing 210008 (China)) 1999Pedosphere1999,9,4:9
12KAI1/CD82 suppresses hepatocyte growth factorinduced migration of hepatoma cells via upregulationof Sprouty2显示文摘We conducted a study concerning the suppressive mechanism of KAI1/CD82 on hepatoma cell metastasis.Hepatocyte growth factor(HGF)induces the migration of hepatoma cells through activation of cellular sphingosine kinase 1(SphK1).Adenovirus-mediated gene transfer of KAI1(Ad-KAI1)downregulates the SphK1 expression and suppresses the HGF-induced migration of SMMC-7721 human hepatocellcular carcinoma cells.Overexpression of KAI1/CD82 significantly elevates Sprouty2 at the protein level.Ablation of Sprouty2 with RNA interference can block the KAI1/CD82-induced suppression of hepatoma cell migration and downregulation of SphK1 expression.It is demonstrated that KAI1/CD82 suppresses HGF-induced migration of hepatoma cells via upregulation of Sprouty2.MU ZhenBin1 ,3,WANG Hua 2,ZHANG Jing 2,LI QingFang 2,WANG LiSheng 2&GUO XiaoZhong 3 1State Key Laboratory of Cancer Biology and Institute of Digestive Diseases,Xijing Hospital,Fourth Military Medical University,Xi’an 710032,China 2Department of Experimental Hematology,Beijing Institute of Radiation Medicine,Beijing 100850,China 3Department of Gastroenterology,Shenyang General Hospital of PLA,Shenyang 110016,China 2008Science China(Life Sciences)2008,51,7:7
13Sediment delivery ratio and its uncertainties on flood event scale:Quantification for the Lower Yellow River显示文摘Sediment delivery ratio(SDR)for fluvial rivers was formulated with sediment rating curve.The observed data of SDR on flood event scale of the Lower Yellow River(LYR)were adopted to examine the formulation and to calibrate the model parameters.A regression formula of SDR was then established and its 95%prediction interval was accordingly quantified to represent its overall uncertainties.Three types of factors including diversity of the incoming flow conditions,river self-regulation processes,and human activities were ascribed to the uncertainties.The following were shown:(1)With the incoming sediment coefficient(ISC)being a variable,it was not necessary to adopt the incoming flow discharge as the second variable in the formulation of SDR;and(2)ISC=0.003 and therefore SDR=2 might be a threshold for distinguishing the characteristics of sediment transport within the LYR.These findings would highlight sediment transport characteristics on the scale of flood event and contribute to uncertainty based analysis of water volume required for sediment transport and channel maintenance of the LYR.FU XuDong 1,JIANG LiWei 1,WU BaoSheng 1,HU ChunHong 2,WANG GuangQian 1 &FEI XiangJun 1 1State Key Laboratory of Hydroscience and Engineering,Tsinghua University,Beijing 100084,China 2China Institute of Hydropower and Water Resources Research,Beijing 100044,China 2010Science China(Technological Sciences)2010,53,3:7
14A property-based attestation protocol for TCM显示文摘This paper presents a property attestation protocol for the security chip TCM (trusted cryptographic module) via analyzing the problems of the current property attestation, which is built on the property attestation model with the online trust third party. In the protocol the prover utilizes the zero-knowledge proof by the attribute certificates, configuration commitment and TCM signature, and attests its configuration and status which are compliant with the declarative security property. The protocol is characterized by shorter signature length and lower computations. The security of the protocol is proved at the random oracle model. The protocol can help extend application and improve standard for security chip TCM, and it also has practical value and immediate significance.FENG DengGuo1,2 & QIN Yu1,2 1State Key Laboratory of Information Security, Institute of Software, Chinese Academy of Science, Beijing 100190, China 2National Engineering Research Center of Information Security, Beijing 100190, China 2010Science China(Information Sciences)2010,53,3:7
15Urban expressway traffic state forecasting based on multimode maximum entropy model显示文摘The accurate and timely traffic state prediction has become increasingly important for the traffic participants,especially for the traffic managements. In this paper,the traffic state is described by Micro-LOS,and a direct prediction method is introduced. The development of the proposed method is based on Maximum Entropy (ME) models trained for multiple modes. In the Multimode Maximum Entropy (MME) framework,the different features like temporal and spatial features of traffic systems,regional traffic state are integrated simultaneously,and the different state behaviors based on 14 traffic modes defined by average speed according to the date-time division are also dealt with. The experiments based on the real data in Beijing expressway prove that the MME models outperforms the already existing model in both effectiveness and robustness.SUN XiaoLiang1,2, JIA LiMin1, DONG HongHui1, QIN Yong1 & GUO Min3 1State Key Laboratory of Rail Traffic Control and Safety, Beijing Jiaotong University, Beijing 100044, China 2School of Traffic and Transportation, Beijing Jiaotong University, Beijing 100044, China 3Beijing Traffic Management Bureau, Beijing 100044, China 2010Science China(Technological Sciences)2010,53,10:6
16Cloning,Sequencing and Expression Analysis of the First Cellulase Gene Encoding Cellobiohydrolase 1 from a Cold-adaptive Penicillium chrysogenum FS010显示文摘cellobiohydrolase 1 基因(cbh1 ) 从毛丛 chrysogenumFS010 被克隆由一修改了 cbhl 有开的读的 .DNAsequencing 表演 1590 bp 装裱的热不对称的交叉聚合酶链反应(TAIL-PCR ) ,编码 529amino 酸残余的通常认为的蛋白质。推出的氨基酸顺序表明 CBHI 与 56 kDa 的一个预言的分子的团有模块化的结构并且由 threonine 与催化的域分开的一个真菌的类型糖类绑定模块组成富有的连接器区域。通常认为的基因产品对在家庭 7 glycosyl hydrolases.A 小说 cbh1 倡导者( 1.3 kb )的真菌的 cellobiohydrolases 相应也被克隆并且定序,它为各种各样的碳来源的碳新陈代谢作用之副产物抑压者 CRE1.Effect 包含七个通常认为的结合部位(5'-SYGGRG-3')到 P.chrysogenum 的 cbh1 抄写被北分析检验,建议 cbh1 的表达式在 transcriptional 被调整水平。在寒冷适应的真菌 P.chysogenum 的 cbh1 基因 accumulatedintracellularly 在 Saccharomyces cerevisiae H158.The recombinant CBHI 被表示为活跃的酶并且不能被分泌进媒介。Yunhua HOU~(1,2) Tianhong WANG~1 Hao LONG~1 and Huiynan ZHU~(1,2) ~1State Key Laboratory of Microbial Technology,Shandong University,Jinan 250100,China ~2Department of Food and Biologic Engineering,Shandong Institute of Light Industry,Jinan 250323,China 2007Acta Biochimica et Biophysica Sinica2007,39,2:6
17Hybrid method of limit equilibrium and finite element internal force for analysis of arch dam stability against sliding显示文摘A hybrid method of limit equilibrium and finite element internal force for analysis of arch dam stability against sliding is presented.The finite element internal force method(FEIFM) is used to provide more accurate thrust forces acting on the faces of a slip body,and the limit equilibrium method(LEM) is employed to evaluate the factor of safety of the slip body.The method presented can deal with a slip body with large amount of geometrically complex slip faces.In addition,compared with the traditional LEM,it can meet the balance condition of the forces in the slip faces.An example shows that the factor of safety obtained by the method presented agrees well with the theoretical solution.A practical example is also presented to demonstrate the application of the method in the stability analysis of an arch dam project.The results from the examples show that the method is promising in analysis of arch dam stability against sliding.BAO TengFei1,2,3,XU BaoSong1,2,3 & ZHENG XueQing1,2,3 1State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering,Hohai University,Nanjing 210098,China 2National Engineering Research Center of Water Resources Efficient Utilization and Engineering Safety,Nanjing 210098,China 3College of Water Conservancy and Hydropower Engineering,Hohai University,Nanjing 210098,China 2011Science China(Technological Sciences)2011,54,4:6
18Spatial prediction and analysis of Himalayan marmot plague natural epidemic foci in China based on HJ-1 satellite data显示文摘Plague,caused by the gram-negative bacterium Yersinia pestis,is a serious and rapidly progressing illness in humans that can be fatal if not treated effectively.The Qinghai-Tibet Plateau is the largest area of natural Himalayan marmot(Marmota himalayana) plague foci in China and covers more than 630000 km2.Akesai County in Gansu Province is a part of this natural focus of plague and was chosen as a study area.Our study used an ecological niche modeling(ENM) approach to predict the potential distribution of the Himalayan marmot.Environment and Disaster Monitor Satellite(HJ-1) data was used to investigate environment factors that affect plague host animal activity.Host animal point data from active surveillance was combined with environmental variables from the HJ-1 satellite and other databases,and the models of the potential distribution of Himalayan marmot were produced with the Genetic Algorithm for Rule-Set Production(GARP).The probability of marmot presence was divided into 0-5%,5%-20%,20%-40%,40%-80%,and 80%-100% subgroups.Areas with 80%-100% probability exhibited the greatest potential for the presence of Himalayan marmot.According to the predicted potential distribution of Himalayan marmot in the study area,active surveillance of plague hosts and plague control and prevention could be more efficient.GAO MengXu1,4,LI XiaoWen1,2,CAO ChunXiang1,ZHANG Hao1,LI Qun3,ZHOU Hang3 HE QiSheng1,4,XU Min1,4,ZHAO Jian1,4,ZHENG Sheng1,4 & CHEN Wei1,4 1State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University,Beijing 100101,China 2School of Geography,Beijing Normal University,Beijing 100875,China 3Office for Disease Control and Emergency Response,Chinese Center for Disease Control and Prevention,Beijing 102206,China 4Graduate University of Chinese Academy of Sciences,Beijing 100049,China 2010Science China Earth Sciences2010,53,S1:5
19Selected issues at the interface between nuclear physics and astrophysics as well as the standard model显示文摘The density functional theory (DFT) with a minimal number of parameters allows a very successful phenomenological description of ground state properties of nuclei all over the periodic table. The recent developments on the application of the covariant density functional theory as well as its extensions by the group in Beijing for a series of interests and hot topics in nuclear astrophysics and nuclear structure are reviewed, including the rapid neutron-capture process, Th/U chronometer, and isospin corrections for superallowed β transitions.MENG Jie1,2,3, NIU ZhongMing1, LIANG HaoZhao1 & SUN BaoHua2,4 1State Key Laboratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871, China 2School of Physics and Nuclear Energy Engineering, Beihang University, Beijing 100191, China 3Department of Physics, University of Stellenbosch, Stellenbosch, South Africa 4Justus-Liebig-Universita¨t Giessen, Heinrich-Buff-Ring 14, Giessen 35392, Germany 2011Science China(Physics,Mechanics & Astronomy)2011,54,S1:5
20Remote sensing based shrub above-ground biomass and carbon storage mapping in Mu Us desert,China显示文摘The estimation of above-ground biomass(AGB) and carbon storage is very important for arid and semi-arid ecosystems.HJ-1A/B satellite data combined with field measurement data was used for the estimation of shrub AGB and carbon storage in the Mu Us desert,China.The correlations of shrub AGB and spectral reflectance of four bands as well as their combined vegetation indexes were respectively analyzed and stepwise regression analysis was employed to establish AGB prediction equation.The prediction equation based on ratio vegetation index(RVI)was proved to be more suitable for shrub AGB estimation in the Mu Us desert than others.Shrub AGB and carbon storage were mapped using the RVI based prediction model in final.The statistics showed the western Mu Us desert has relatively high AGB and carbon storage,and that the gross shrub carton storage in Mu Us desert reaches 16 799 200 t,which has greatly contributed to the carbon fixation in northern China.XU Min 1,2,CAO ChunXiang 1,TONG QingXi 1,LI ZengYuan 3,ZHANG Hao 1,HE QiSheng 1,2,GAO MengXu 1,2,ZHAO Jian 1,2,ZHENG Sheng 1,2,CHEN Wei 1,2 & ZHENG LanFen 1 1State Key Laboratory of Remote Sensing Science,Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University,Beijing 100101,China 2 Graduate School of the Chinese Academy of Sciences,Beijing 100049,China 3 Research Institute of Forest Resources and Information Techniques,Chinese Academy of Forestry,Beijing 10009,China 2010Science China(Technological Sciences)2010,53,S1:5
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