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Expression pattern and core region analysis of AtMPK3 promoter in response to environmental stresses

Science china(life sciences) 2010年第11期53卷 1315-1321页

作者： GAO Fei1,2, SU Qi1, FAN YunLiu1& WANG Lei1 1Biotechnology Research Institute/National Key Facility for Crop Gene Resources and Genetic Improvement, Chinese Academy of Agricultural Science, beijing 100081, china 2college of life and Environmental sciences, Minzu university of china, beijing 100081, china Biotechnology Research Institute/National Key Facility for Crop Gene Resources and Genetic Improvement Chinese Academy of Agricultural Science Beijing China college of life and Environmental sciences Minzu University of China Beijing China

The protein kinase AtMPK3,a component of the MAP kinase cascade,plays an important role in stress signal transduction in plant cells. To clarify how AtMPK3 is regulated at the transcriptional level in response to various environmental factors, the 1016-bp promoter sequence upstream of the transcription start site of the AtMPK3 gene was isolated. Analyses of the promoter sequence using plant promoter databases revealed that the AtMPK3 promoter contains many potential cis-acting elements involved in environmental stress responses. We constructed four deletion mutants of the AtMPK3 promoter, and introduced the intact and truncated promoter sequences fused to the β-glucuronidase (GUS) gene into Arabidopsis. GUS histochemical staining and quantitative fluorometric GUS assays were performed to visualize and compare the expression patterns in response to different environmental stimuli. The region between-188 and-62 upstream of the transcription start site was identified as the essential DNA sequence of the AtMPK3 promoter for responses to drought, high salinity, low temperature, and wounding. These results advance our understanding of the molecular mechanisms controlling AtMPK3 expression in response to different environmental stimuli.

关键词： Arabidopsis thaliana AtMPK3 promoter stress

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Dynamic mechanisms of the post-seismic deformation following large events:Case study of the 1999 Chi-Chi earthquake in Taiwan of china

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Science china Earth sciences 2009年第11期52卷 1813-1824页

作者： ZHU ShouBiao1,2 & CAI YongEn2 1 Institute of Crustal Dynamics, china Earthquake Administration, beijing 100085, china 2 Department of Geophysics, peking university, beijing 100871, china Institute of Crustal Dynamics China Earthquake Administration Beijing China Department of Geophysics Peking University Beijing China

The mechanism of postseismic deformation related to strong earthquakes is important in geodynamics, and presumably afterslip or viscoelastic relaxation is responsible for the postsesimic deformation. The 1999 Chi-Chi, Taiwan of china, earthquake occurred in the region where GPS observation station is most densely deployed in the world. The unprecedented GPS data provides a unique opportunity to study the physical processes of postseismic deformation. Here we assume that the interactions of viscoelastic relaxation, afterslip, fault zone collapse, poroelastic rebound, flow of underground fluids, and all these combined contribute to the surface displacements following the main shock. In order to know the essence of the postseismic deformation after the strong event, fault zone collapse, poroelastic rebound, flow of underground fluids, and so on, are represented equivalently by the variations of the focal medium properties. Therefore, the viscoelastic relaxation, afterslip, and the variations of the equivalent focal medium properties are inverted by applying the GPS temporal series measurement data with viscoelastic finite element method. Both the afterslip rate distribution along the fault and the afterslip evolution with time are obtained by means of inversion. Also, the preliminary result suggests that viscosities of the lower crust and the upper mantle in Taiwan region is 2.7×1018 and 4.2×1020 Pa·s, respectively. Moreover, the inversion results indicate that the afterslip contributing to postseismic deformation of 44.6% in 450 days after the Chi-Chi earthquake, with 34.7% caused by the viscous relaxation and 20.7% by other factors such as fault zone collapse, poroelastic rebound, and the flow of liquids.

关键词： mechanism of postseismic deformation viscoelastic finite element method GPS temporal series data Chi-Chi earthquake

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Palynological characters of Glycyrrhiza,Glycyrrhizopsis,and Meristotropis(Leguminosae),with special reference to their taxonomic significance

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Journal of Systematics and Evolution 2010年第6期48卷 455-463页

作者： 1,2Lei MENG 2Xiang-Yun ZHU 1(college of Biological sciences,china Agricultural university,beijing 100094,china) 2(Institute of Botany,Chinese Academy of sciences,beijing 100093,china) (college of Biological sciences China Agricultural University Beijing 100094 China) (Institute of Botany Chinese Academy of Sciences Beijing 100093 China)

The pollen morphology of 11 species of the genus Glycyrrhiza *** one from each of the genera Glycyrrhizopsis Boiss.& *** Meristotropis Fisch.& *** investigated by scanning electron *** pollen morphology,the main differences between Glycyrrhizopsis and Glycyrrhiza are:Glycyrrhizopsis-pollen grains 36.63 × 40.42 μm in size,oblate spheroidal in shape;and Glycyrrhiza-pollen grains 24.47-33.18 × 23.82-31.83 μm in size,prolate spheroidal in *** and Glycyrrhiza should be recognized as two distinct genera based on palynological and morphological *** and Glycyrrhiza are similar in many important palynological and morphological characters,suggesting that the two should be *** Glycyrrhiza,two types of pollen grains,3-lobed-circular or subtriangular in polar view,are found in different species,in accordance with morphological differences in the two groups,shedding light on the classification and evolution of the genus.

关键词： exine sculpture morphological character pollen morphology taxonomic revision.

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Water demand for ecosystem protection in rivers with hyper-concentrated sediment-laden flow

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Science china(Technological sciences) 2004年第Z1期47卷 186-198页

作者： LUO Huaming, LI Tianhong, NI Jinren & WANG Yudong Department of Environmental Engineering, peking university, beijing 100871, china The Key Laboratory of Water and Sediment sciences, Ministry of Education, beijing 100871, china Department of Environmental Engineering Peking University Beijing China The Key Laboratory of Water and Sediment sciences Ministry of Education Beijing China

Sediment transport is one of the main concerns in a river system with hyper-concentrated flows. Therefore, the water use for sediment transport must be considered in study on the water demand for river ecosystem. The conventional methods for calculating the Minimum Water Demand for River Ecosystem (MWDRE) are not appropriate for rivers with high sediment concentration. This paper studied the MWDRE in wet season, dry season and the whole year under different water-and-sediment conditions in the Lower Yellow River, which is regarded as a typical river with sediment-laden flows. The characteristics of MWDRE in the river are analyzed. Firstly, the water demand for sediment transport (WDST) is much larger than the demands for other riverine functions, the WDST accounts for the absolute majority of the MWDRE. Secondly, in wet season when the WDST is satisfied, not only most of the annual incoming sediment can be transported downstream, but also the water demands for other river functions can be satisfied automatically, so that the MWDRE in wet season is identical to the WDST. Thirdly, in dry season, when the WDST is satisfied, the water demands for other river functions can also be satisfied, but the low sediment transport efficiency results in significant waste of water resources. According to these characteristics and aiming at decreasing sediment deposition in the riverbed and improving the utilization efficiency of water resources, hydrological engineering works can be used to regulate or control flow and sediment so that the sediment incoming in dry season can be accumulated and be transported downstream intensively and thus efficiently in wet season.

关键词： sediment-laden flow, the Lower Yellow River, water demand for river ecosystem, water demand for sediment transport

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Mapping the Antigenic Peptides of Sm26/2 in Glutathione S-Transferases of Schistosoma Mansoni

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Chinese Chemical Letters 1998年第4期9卷 377-379页

作者： Jia Xi XU Meng Shen CAI(college of Chemistry and Molecular Engineering, peking university, beijing 100871 (School of Pharmaceutical sciences, beijing Medical university, beijing 100083) Coll. of Chem./Molec. Engineering Peking University Beijing 100871 China School of Pharmaceutical sciences Beijing Medical University Beijing 100083 China

Six antigenic peptides of Sm26/2 glutathione S-transferase of schistosoma mansoni have been predicted according to their hydrophilicity, flexibility, accessibility, charge distribution and beta-turn in the secondary structure by the determination of its primary structure, and synthesized by solid phase method. Two of them showed good antigenicity by Dot-ELISA. They would be candidate peptides of synthetic anti-schistosomal vaccine.

关键词： schistosoma mansoni glutathione S-transferase antigenic peptide peptide vaccine

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An efficient algorithm for finding the largest chain graph according to a given chain graph

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Science china Mathematics 2005年第11期48卷 1517-1530页

作者： LIU Baijun,ZHENG Zhongguo & ZHAO Hui School of Mathematical sciences, peking university, beijing 100871, china Department of Statistics, Central china Normal university, Wuhan 430079, china School of Mathematical sciences Peking University Beijing China Department of Statistics Central China Normal University Wuhan China

Chain graph (CG) is a general model of graphical Markov models. Some different chain graphs may describe the same conditional independence structure, then we say that these CGs are Markov equivalent. In 1990 Frydenberg showed that every class of Markov equivalent CGs has a CG which is called the largest chain graph with the greatest number of lines. This paper presents an efficient algorithm for finding the largest chain graph of the corresponding Markov equivalent class of a given CG. The computational complexity of the algorithm is O(n3). It is more efficient than the complexity O(n!) of the present algorithms. Also a more intuitive graphical characterization of the largest chain graph is provided based on the algorithm in this paper.

关键词： graphical Markov model,chain graph,largest chain graph,protected arrows,efficient algorithm

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Status of study on biological and toxicological effects of nanoscale materials

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Science china Chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2 & JIA Guang3 1. Laboratory for Bio-Environmental Health sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of sciences, beijing 100049, china 2. college of Chemistry and Molecular Engineering, peking university, beijing 100871, china 3. Department of Occupational and Environmental Health sciences, School of Public Health, peking university, beijing 100083, china Laboratory for Bio-Environmental Health sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences Beijing China college of Chemistry and Molecular Engineering Peking University Beijing China Department of Occupational and Environmental Health sciences School of Public Health Peking University Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

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Probabilistic composition of cone-based cardinal direction relations

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Science china(Technological sciences) 2008年第S1期51卷 81-90页

作者： LIU Yu1,TIAN Yuan1 & WENG JingNong2 1 Institute of Remote Sensing and Geographical Information Systems,peking university,beijing 100871,china 2 college of Software,Beihang university,beijing 100083,china Institute of Remote Sensing and Geographical Information Systems Peking University Beijing China college of Software Beihang University Beijing China

Composition tables play a significant role in qualitative spatial reasoning (QSR). At present,a couple of composition tables focusing on various spatial relations have been developed in a qualitative approach. However,the spatial reasoning proc-esses are usually not purely qualitative in everyday life,where probability is one important issue that should be considered. In this paper,the probabilistic compo-sitions of cone-based cardinal direction relations (CDR) are discussed and esti-mated by making some assumptions. Consequently,the form of composition result turns to be {(R1,P1),(R2,P2),…,(Rn,Pn)},where Pi is the probability associated with relation Ri. Employing the area integral method,the probabilities in each composi-tion case can be computed with the assumption that the target object is uniformly distributed in the corresponding cone regions.

关键词： spatial reasoning cardinal direction relations probabilistic composition

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Abrupt climate change and collapse of ancient civilizations at 2200BC-2000BC

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Progress in Natural Science:Materials International 2005年第10期15卷 46-52页

作者： WANG Shaowu (Department of Atmospheric Science, School of Physics, peking university, beijing 100871, china) Department of Atmospheric Science School of Physics Peking University Beijing 100871 China

Plentiful evidence of historical, archaeological and palaeoclimatic studies proved that an abrupt change from wetter to drier climate occurred over the Nile Valley,the Mesopotamia, the Indus Valley and Huanghe River Valley at 2200BC-2000BC. The abrupt change was developed based on the general lowering of temperature in the middle latitudes, and was a strong cold event since the beginning of the Megathermal (8.5-3.0 kaBP). Collapse of Nile civilization appeared at the First Intermediate Period (2181BC-2040BC). Civilization of Mesopotamia began collapse following the disintegration of Akkadian Empire. This process lasted to the foundation of Babylon Kingdom from 2200BC to 1900BC. Indus civilization abruptly fell off at 1800BC. A widespread alternation of archaeological cultures happened in china at ca. 2000BC except only in its central part. Longsheng culture was replaced by the Erlitou culture, which is now acknowledged in china as Xia Culture. Foundation of Xia Dynasty at 2070BC opened a new chapter in the development of Chinese civilization. Studies indicated that abrupt climate change may be caused by the weakening of the Thermohaline Circulation (THC).

关键词： 2200BC-2000BC abrupt climate change collapse of ancient civilization.

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Balanced multiple description subband coding based on multifilter banks

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Science china(Information sciences) 2011年第11期54卷 2359-2372页

作者： WANG Ning 1,LI BaoBin 2 & PENG LiZhong 1 1 LMAM,School of Mathematical sciences,peking university,beijing 100871,china 2 School of Information Science and Engineering,Graduate university of Chinese Academy of sciences,beijing 100190,china LMAM School of Mathematical Sciences Peking University Beijing China School of Information Science and Engineering Graduate University of Chinese Academy of Sciences Beijing China

Multiple description coding is one of the source coding techniques to alleviate the problems of packet loss in *** encoder generates several different descriptions of the source and the decoder can produce a useful reconstruction with any received subset of these *** of the earlier works concentrated on redundancy and the average distortion of the single-description reconstructions,which is insufficient to describe the *** this paper,a metric of the coding system,balance eccentric modulus,is defined to evaluate the difference in quality between the individual *** the discrete wavelet transform becomes trivial polyphase transform when setting the balance eccentric modulus at zero,we introduce a multiwavelet based scheme ***,a sufficient condition for balanced multiwavelet based multiple description coding is presented.

关键词： multiple description coding rate-distortion theory balance eccentric modulus balanced multiwavelet multifilter bank

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