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Prediction of Debris-flow Danger Area by Combining Hydrological and Inundation Simulation Methods

Journal of Mountain Science 2011年第1期8卷 1-9页

作者： CUI Peng key laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of Sciences Chengdu 610041 China institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China graduate school of{2. Beijing 100049 China

Debris flows have caused serious human casualties and economic losses in the regions strongly affected by the Ms8.0 Wenchuan earthquake of 2.o8. Debris flow mitigation and risk assessment is a key issue for reconstruction. The existing methods of inundation simulation are based on historical disasters and have no power of prediction. The rain- flood method can not yield detailed flow hydrograph and does not meet the need of inundation simulation. In this paper, the process of water flow was studied by using the Arc-SCS model combined with hydraulic method, and then the debris flow runoff process was calculated using the empirical formula combining the result from Arc-SCS. The peak discharge and runoff duration served as input of inundation simulation. Then, the dangerous area is predicted using kinematic wave method and Manning equation. Taking the debris flow in Huashiban gully in Beichuan County, Sichuan Province, china on 2. Sep. 2.o8 as example, the peak discharge of water flow and debris flow were calculated as 3..52.m3.s-1 and 2.5.66 m3.s-, with error of 4.15% compared to the measured values. The simulated area of debris-flow deposition was 161,500 m2. vs. the measured area of 14.,097 m2. in error of 81.75%. The simulated maximum depth was 12.3.m, consistent with the real maximum depth between lO and 15 m according to the field survey. The minor error is mainly due to the flow impact on buildings and variations in cross-section configuration. The present methodology can be applied to predict debrisflow magnitude and evaluate its risk in other watersheds inthe earthquake area.

关键词： Debris flow Arc-SCS model Inundation simulation Risk analysis Wenchuan earthquake

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BUD2.encoding an S-adenosylmethionine decarboxylase,is required for Arabidopsis growth and development

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Cell Research 2006年第5期16卷 446-456页

作者： Chunmin Ge~(1,2.*) Xia Cui~(1,2.*) Yonghong Wang~1 Yuxin Hu~3.Zhiming Fu~1 Dongfen Zhang~(1,2. Zhukuan Cheng~1 Jiayang Li~1 ~1State {3. laboratory of Plant Genomics and National Center for Plant Gene Research,{2. of Genetics and Developmental Biology,chinese academy of sciences,Beijing 100101,china ~2.7} school,chinese academy of sciences,Beijing 100101,china ~3.2. of Botany,chinese academy of sciences,Beijing 100093.china State key laboratory of Plant Genomics and National Center for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing China graduate school Chinese Academy of Sciences Beijing China institute of Botany Chinese Academy of Sciences Beijing China

Polyamines are implicated in regulating various developmental processes in plants,but their exact roles and how theygovern these processes still remain *** report here an Arabidopsis bushy and dwarf mutant,bud2.which resultsfrom the complete deletion of one member of the small gene family that encodes S-adenosylmethionine decarboxylases(SAMDCs) necessary for the formation of the indispensable intermediate in the polyamine biosynthetic ***2.plant has enlarged vascular systems in inflorescences,roots,and petioles,and an altered homeostasis *** double mutant of bud2.and samdcl,a knockdown mutant of another SAMDC member,is embryo lethal,demonstrat-ing that SAMDCs are essential for plant *** results suggest that polyamines are required for the normalgrowth and development of higher plants.

关键词： BUD2 polyamines embryogenesis plant architecture Arabidopsis

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Prevention of lipopolysaccharide-induced injury by 3.5-dicaffeoylquinic acid in endothelial cells

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Acta Pharmacologica Sinica 2007年第8期28卷 1143-1148页

作者： Ruo-peng ZHA~(1,2. Wei XU~(1,2. Wen-yi WANG~(1,2. Li DONG~1 Yi-ping WANG~(1,3. ~1State {3. laboratory of Drug Research,Shanghai {2. of Materia Medica,Shanghai {2.s for Biological sciences,chinese academy of Seiences,Shanghai 2.12.3.{14. ~2.8} school of the chinese academy of sciences,Shanghai 2.12.3.{14. State key laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China graduate school of the{2. Shanghai China

Aim:To investigate the effect of 3.5-dicaffeoylquinic acid（3.5-diCQA）onlipopolysaccharide（LPS）-induced injury in human dermal microvascular endothe-lial cells（HMEC-I）.Methods:The anti-oxidant effect was detected using themalondialdehyde（MDA）assay in a rat liver microsome model of lipid *** viability was analyzed using the 3.（4.5-dimethylthiazol-2.yl）-2.5diphenyltetrazolium bromide *** lipid peroxide injury was measured bylactate dehydrogenase（LDH）*** cells were detected by flowcytometry,and confirmed by DNA fragmentation ***-3.activitywas measured using a specific assay *** level of intracellular reactive oxygenspecies（ROS）was determined by flow cytometry with a 2.7-dichlorodihydro-fluorescein diacetate fluorescence ***:The exposure of microsomesto ascorbate-Fe2.resulted in lipoperoxidation according to an increase in the levelof *** formation decreased in a dose-dependent manner on treatmentwith 5,10,or 50μmol/L 3.*** with LPS for 16 h resulted in a 60%decrease in cell viability and an increase in LDH release from 4..6% to 61.5%.DNA laddering was observed by agarose gel *** level ofapoptotic cells peaked at 2.% after treatment with LPS for 12.*** treat-ment with LPS for 12.h,intracellular ROS and caspase-3.activity ***-treatment with 3.5-diCQA at 5,10,or 50μmol/L for 1 h attenuated LPS-mediatedendothelial cell *** anti-apoptotic action of 3.5-diCQA was partiallydependent on its capacity for anti-oxidation and the suppression of ***:3.5-diCQA displays anti-oxidative and anti-apoptotic activ-ity in HMEC-1 due to scavenging of intracellular ROS induced by LPS,and thesuppression of caspase-3.activity.

关键词： 3 5-dicaffeoylquinic acid lipopolysaccharide human dermal microvascular endo-thelial cells reactive oxygen species apoptosis caspase-3

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A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

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Science china Earth sciences 2011年第2期54卷 223-227页

作者： WANG Li1,2.& LENG Qin1,3.1 State key laboratory of Palaeobiology and Stratigraphy,Nanjing {2. of Geology and Palaeontology,chinese academy of sciences,Nanjing 2.0008,china 2.graduate school of chinese academy of sciences,Beijing {13.,china 3.Department of Science and Technology,Bryant University,Smithfield RI 02.17,USA State key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing China graduate school of{2. Beijing China Department of Science and Technology Bryant University Smithfield USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon- struction. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2.concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeo- climatological research. Here, we describe a new method using clear nail polish as a medium to ＂strengthen＂ the originally thin and fragile cuticles prior to maceration procedures. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living repre- sentative, 114. glyptostroboides, as a comparative reference, bas been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词： fossil leaf cuticle Metasequoia new method thin and fragile cuticle SEM observation stomatal frequency CO2

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Synthesis of well-defined functional PE graft copoly-mers via ATRP process

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Science Bulletin 2005年第10期50卷 1048-1051页

作者： CAO Chengang1, 2. DONG Jinyong1 & HU Youliang1 1. CAS key laboratory of Engineering Plastics, Joint laboratory of Polymer Science and Materials, {4. of Chemistry, chinese academy of sciences, Beijing 100080, china 2. graduate school, chinese academy of sciences, Beijing 10003., china CAS key laboratory of Engineering Plastics Joint Laboratory of Polymer Science and Materials Institute of Chemistry Chinese Academy of Sciences Beijing China graduate school Chinese Academy of Sciences Beijing China

In summary, we have demonstrated a convenient yet highly efficient method for the preparation of PE-based graft copolymers via ATRP. By introducing a small amount of styrene groups into PE chains via the selective copolymerization of ethylene with 1,4.divinylbenzene catalyzed by Et(Ind)2.rCl2.MAO, the multifunctional ATRP initiator of 1-chloroethylbenzene-containing PE was readily achieved by a quantitative hydrochlorination reaction and was shown to be very effective for the initiation of graft polymerization of MMA and styrene to prepare structurally well-defined PE-based graft copolymers.

关键词： ATRP Synthesis of well-defined functional PE graft copoly-mers via ATRP process PE well

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Progress in the detection of human genome structural variations

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Science china(Life sciences) 2009年第6期52卷 560-567页

作者： WU XueMei1,3.& XIAO HuaSheng1,2.1 Center of Functional Genomics,key laboratory of System Biology,Shanghai {2.s for Biological sciences,chinese academy of sciences,Shanghai 2.003.,china 2.National Engineering Center for Biochip at Shanghai,Shanghai 2.12.3.china 3.graduate school of the chinese academy of sciences,Shanghai 2.003.,china Center of Functional Genomics Key Laboratory of System Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China graduate school of the{2. Shanghai China National Engineering Center for Biochip at Shanghai Shanghai China

The emerging of high-throughput and high-resolution genomic technologies led to the detection of submicroscopic variants ranging from 1 kb to 3.Mb in the human *** variants include copy number variations(CNVs),inversions,insertions,deletions and other complex rearrangements of DNA *** paper briefly reviews the commonly used technologies to discover both genomic structural variants and their potential ***,we highlight the array-based,PCR-based and sequencing-based assays,including array-based comparative genomic hybridization(aCGH),representational oligonucleotide microarray analysis(ROMA),multiplex amplifiable probe hybridization(MAPH),multiplex ligation-dependent probe amplification(MLPA),paired-end mapping(PEM),and next-generation DNA sequencing ***,we discuss the limitations and challenges of current assays and give advices on how to make the database of genomic variations more reliable.

关键词： structural variation cytogenetic microarray PCR paired end mapping(PEM) next-generation sequencing

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Convergence analysis of the adaptive finite element method with the red-green refinement

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Science china Mathematics 2010年第2期53卷 499-512页

作者： ZHAO XuYing 1, 3., HU Jun 2.? & SHI ZhongCi 1 1 State key laboratory of Scientific and Engineering Computing, {2. of Computational Mathematics and Scientific/Engineering Computing, academy of Mathematics and Systems Science, chinese academy of sciences, Beijing 100190, china 2.key laboratory of Mathematics and Applied Mathematics (Peking University), Ministry of Education and school of Mathematical sciences, Peking University, Beijing 100871, china 3.{13. University of chinese academy of sciences, Beijing 100190, china State key laboratory of Scientific and Engineering Computing Institute of Computational Mathematics and Scientific/Engineering Computing Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing China graduate University of chinese academy of sciences Beijing China key laboratory of Mathematics and Applied Mathematics (Peking University) Ministry of Education and School of Mathematical Sciences Peking University Beijing China

In this paper, we analyze the convergence of the adaptive conforming P 1 element method with the red-green refinement. Since the mesh after refining is not nested into the one before, the Galerkin-orthogonality does not hold for this case. To overcome such a difficulty, we prove some quasi-orthogonality instead under some mild condition on the initial mesh (Condition A). Consequently, we show convergence of the adaptive method by establishing the reduction of some total error. To weaken the condition on the initial mesh, we propose a modified red-green refinement and prove the convergence of the associated adaptive method under a much weaker condition on the initial mesh (Condition B).

关键词： red-green refinement adaptive finite element method convergence non-nested local refinement

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fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2.3., ZHAO Xia~4. SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. key laboratory of Nuclear Analysis Techniques, {2. of High Energy Physics, chinese academy of sciences, Beijing 10004., china 2. graduate school of chinese academy of sciences, Beijing 10004., china 3. Department of Physics, Zhoukou Normal University, Zhoukou 4.6100, china 4. Research Imaging Center, University of Texas Health Science Center, San Antonio, Texas 782.9, USA 5. National ASIC Design and Engineering Center, {2. of Automation, chinese academy of sciences, Beijing 10004., china 6. Department of Physics, Zhejiang University, Hangzhou 3.002., china) key laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China graduate school of{2. Beijing 100049 China Department of Physics Zhoukou Normal University Zhoukou 466100 China Research Imaging Center University of Texas Health Science Center San Antonio TX 78229 United States National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing 100049 China Department of Physics Zhejiang University Hangzhou 310027 China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

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Characterization of a sodium-regulated glutaminase from cyanobacterium Synechocystis sp. PCC 6803

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Science china(Life sciences) 2008年第12期51卷 1066-1075页

作者： ZHOU Jie1, ZHOU JunXia1,2. YANG HaoMeng1, YAN ChengShi1 & HUANG Fang1 1 key laboratory of Photosynthesis and Environmental Molecular Physiology, {2. of Botany,{4., Beijing 100093. china 2.graduate school of{4., Beijing 10003., china key laboratory of Photosynthesis and Environmental Molecular Physiology Institute of Botany Chinese Academy of Sciences Beijing China graduate school of{2. Beijing China

Glutaminase is widely distributed among microorganisms and mammals with important functions. Lit-tle is known regarding the biochemical properties and functions of the deamidating enzyme glutami-nase in cyanobacteria. In this study a putative glutaminase encoded by gene slr2.79 in Synechocystis sp. PCC 6803.was investigated. The slr2.79 was expressed as histidine-tagged fusion protein in Es-cherichia coli. The purified protein possessed glutaminase activity, validating the functional assign-ment of the genomic annotation. The apparent Km value of the recombinant protein for glutamine was 2..6 ± 0.9 mmol/L, which was comparable to that for some of other microbial glutaminases. Analysis of the purified protein revealed a two-fold increase in catalytic activity in the presence of 1 mol/L Na+. Moreover, the Km value was decreased to 12.2.± 1.9 mmol/L in the presence of Na+. These data demon-strate that the recombinant protein Slr2.79 is a glutaminase which is regulated by Na+ through in-creasing its affinity for substrate glutamine. The slr2.79 gene was successfully disrupted in Synecho-cystis by targeted mutagenesis and the △slr2.79 mutant strain was analyzed. No differences in cell growth and oxygen evolution rate were observed between △slr2.79 and the wild type under standard growth conditions, demonstrating slr2.79 is not essential in Synechocystis. Under high salt stress condition, however, △slr2.79 cells grew 1.2.-fold faster than wild-type cells. Moreover, the photosyn-thetic oxygen evolution rate of △slr2.79 cells was higher than that of the wild-type. To further charac-terize this phenotype, a number of salt stress-related genes were analyzed by semi-quantitative RT-PCR. Expression of gdhB and prc was enhanced and expression of desD and guaA was repressed in △slr2.79 compared to the wild type. In addition, expression of two key enzymes of ammonium assimi-lation in cyanobacteria, glutamine synthetase (GS) and glutamate synthase (GOGAT) was examined by semi-quant

关键词： cyanobacteria Synechocystis putative glutaminase enzyme activity mutagenesis salt tolerance

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Estimation of forest volumes by integrating Landsat TM imagery and forest inventory data

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Science china(Technological sciences) 2006年第Z1期49卷 54-62页

作者： GU Huiyan, DAI Limin, WU Gang, XU Dong, WANG Shunzhong &WANG Hui institute of Applied Ecology, chinese academy of sciences, Shenyang 110016,{2. {3. of Forestry, Northeast Forestry University, Harbin 15004.,{2. State key Lab of Systems Ecology, Research Center for Eco-Environmental sciences, chinese academy of sciences, Beijing 100085,{2. graduate University of chinese academy of sciences, Beijing 10003.,{2. institute of Applied Ecology Chinese Academy of Sciences Shenyang China school of Forestry Northeast Forestry University Harbin China State key Lab of Systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing China graduate University of chinese academy of sciences Beijing China

Accurate information about forest volumes is essential for forest management planning. The survey interval of the Forest Resource Inventory of china (FRIC) is too long to meet the demand for timely decision-making required for forest protection, management, and utilization. Analysis of satellite imagery provides good potential for more frequent reporting of forest parameters. In this study, we describe an application of the k-nearest neighbors (kNN) method to Landsat TM imagery for improving estimation of forest volumes. Several spectral features were tested and compared in forest volume estimations, including normalized difference vegetation index, environmental vegetation index, and the combination of the spectral features. The combined index resulted in the most accurate volume estimations. The kNN estimator and the combined index were then used in forest volume estimation. The estimation error (RMSE) of the total volume was4..2., much lower than those for Larix forest (the RMSE was 51.7%) and those for the Korean pine and broadleaved forests (the estimation errors were over 71.7% and 88.19%,respectively). This preliminary study demonstrates the potential of forest volume estimations with remote sensing data to provide useful information for forest management if only limited ground information is available.

关键词： forest inventory, landsat TM, k-nearest neighbors, spectral extraction.

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