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Analysis of Gene Expression Profile Induced by Water Stress in Upland Rice(Oryza sativa ***109)Seedlings using Subtractive Expressed Sequence Tags Library

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Journal of Integrative Plant Biology 2007年第10期49卷 1455-1463页

作者： Haiguang Wang Hongliang Zhang Zichao Li key laboratory of Crop Genomics and Genetic Improvement of Ministry of Agriculture key laboratory of Crop Heterosis and Utilizition of Ministry of Education and Beijing key lab of Crop Genetic Improvement China Agricultural University Beijing China100094

To identify the water stress induced genes of upland rice cultivar IRAT109, which is resistant to drought, a subtractive cDNA library was developed from polyethylene glycol- （PEG） treated and non-treated seedlings by suppression subtractive hybridization, from which 2112 recombinant colonies were obtained, Eight hundred clones were selected randomly for sequencing analysis, and 384 unique expressed sequence tags （ESTs） were obtained, They were found to be involved in diverse biological processes, such as metabolism, transcription, signal transduction, protein synthesis and others, Notably a number of known functional genes in drought tolerance, including genes related to biosynthesis of osmoprotectants, defense against active oxygen, removal of toxic compounds, recovery of proteins and reinforcement of cell wall were also found in the study, Several genes related to deleterious responses were upregulated by PEG stress, The differential expression patterns of 11 SSH-derived ESTs were confirmed by real-time polymerase chain reaction.

关键词： expressed sequence tag subtracted library suppression subtractive hybridization upland rice water stress.

A Distributed Monthly Water Balance Model for Analyzing Impacts of Land Cover Change on Flow Regimes

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Pedosphere 2005年第6期15卷 761-767页

作者： XIA Jun WANG Gang-Sheng YE Ai-Zhong NIU Cun-Wen key lab. of Water Cycle ＆ Related Land Surface Processes Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China）. State key lab. of Water Resources ＆ Hydropower Engineering Sciences Wuhan University Wuhan 430072 （China）

The Miyun Reservoir is the most important water source for Beijing Municipality, the capital of China with a population of more than 12 million. In recent decades, the inflow to the reservoir has shown a decreasing trend, which has seriously threatened water use in Beijing. In order to analyze the influents of land use and cover change (LUCC) upon inflow to Miyun Reservoir, terrain and land use information from remote sensing were utilized with a revised evapotranspiration estimation formula; a water loss model under conditions of human impacts was introduced; and a distributed monthly water balance model was established and applied to the Chaobai River Basin controlled by the Miyun Reservoir. The model simulation suggested that not only the impact of land cover change on evapotranspiration, but also the extra water loss caused by human activities, such as the water and soil conservation development projects should be considered. Although these development projects were of great benefit to human and ecological protection, they could reallocate water resources in time and space, and in a sense thereby influence the stream flow.

关键词： distributed monthly water balance model land use and cover change (LUCC) remote sensing scenario analysis

Quantitative geochemical reconstruction of Eocene paleoenvironment in Fushun Basin,northeast China

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Acta Geochimica 2024年第3期43卷 571-587页

作者： Yuanji Li Pingchang Sun Qiang Zhang Junxian Wang Department of Safety Engineering Heilongjiang University of Science and TechnologyHarbin 150022China National Professional Center lab of Safety Basic Research for Hydrocarbon Gas Pipeline Transportation Network Harbin 150022China College of Earth Sciences Jilin UniversityChangchun 130061JilinChina Beijing Research Institute of Uranium Geology Beijing 100029China

The quantitative estimation of key parameters of paleotemperature and paleoprecipitation is crucial for paleoclimate *** data from mod-ern sediments are highly consistent with climate data,and their relationship can provide an important reference for the quantitative reconstruction of the *** this study,detailed inorganic geochemical analysis was carried out using high-precision sampling of the Paleogene(LFD-1 well)Guchengzi,Jijuntun and Xiloutian Formations in the Fushun Basin located in the mid-latitudes of the Northern *** Eocene Guchengzi Formation(54.51–47.8 Ma)and Jijuntun Formation(47.8–41.2 Ma)in the Fushun Basin were found to have been deposited under a humid *** lower(41.2–40.1 Ma)and upper(40.1–37.8 Ma)parts of the Xiloutian Formation were character-ized by semiarid and semihumid–semiarid climates,respec-tively,which is very similar to the paleoclimatic information reflected by organic carbon *** Eocene Thermal Maximum 2(ETM2,~53.7 Ma),Early Eocene Climatic Optimum(EECO,~53.1–46.5 Ma),Eocene Thermal Maxi-mum 3(ETM 3,~52.8 Ma),and Middle Eocene Climatic Optimum(MECO,~40.7–40.1 Ma)events significantly enhanced chemical weathering during these *** rapid increase in pCO_(2)concentration leads to an increase in temperature,precipitation,and surface runoff,exhibiting strong chemical *** mean annual temperature(MATa)and mean annual precipitation(MAPa,MAPb,and MAPc)were estimated using parameters,such as the corrosion index without potassium(CIA-K),CaO/Al_(2)O_(3),and(Na_(2)O+K_(2)O)/Al_(2)O_(3).Comparing MAPa,MAPb,and MAPc with the MAP estimated using pollen data,MAPa and MAPb were found to be more sensitive to the climate during high precipitation periods(precipitation>1000 mm,Guchengzi Formation),and the recovered average precipi-tation was similar to *** contrast,MAPc was more sensitive to the climate during low precipitation periods(precipitation<1000 mm,Jijuntun,and Xilouti

关键词： Eocene Fushun Basin Major element Paleoclimate Geochemical reconstruction

2000-2020年中国建设用地扩张侵占耕地的时空特征及其与粮食产量的空间关系

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Journal of Geographical Sciences 2024年第5期34卷 855-870页

作者：李资华丁明军谢坤李静茹陈利文 Territorial Spatial Survey and Planning Institute Department of Natural Resources of Jiangxi ProvinceNanchang 330025China Engineering Technology Innovation Center for Ecological Protection and Restoration of Land Space in the Great Lakes Basin Ministry of Natural ResourcesNanchang 330025China School of Geography and Environment Jiangxi Normal UniversityNanchang 330028China key lab of Poyang Lake Wetland and Watershed Research of Ministry of Education and School of Geography and Environment Jiangxi Normal UniversityNanchang 330028China Yuzhang Normal University Nanchang 330103China Nanjing Engineering Vocational College of Jiangsu Province Nanjing 211135China

Construction land expansion is a key driver of urbanization and industrialization,yet it poses the risk of losing farmland and cascading impacts on food *** spatial char-acteristics of farmland occupied by construction land and its association with grain yield in China were *** analyzed the characteristics of farmland converted into construction land,and its relationship with grain yield in China for *** land increased in area in central and western regions of China,and farmland decreased in area in south-eastern *** expansion of construction land in the North China Plain,Northeast China Plain,and the Loess Plateau,occurred at the expense of *** the southeast coast of China,grain yield increase was only weakly dependent on farmland *** in which farmland was converted into construction land and grain-yield change were highly coupled in southeastern coastal China,Sichuan Basin,Shandong Peninsula,and the Hu Huanyong *** should be noted that expansion in construction land area does have some influence on grain production;ultimately it is greatly affected by yield per unitarea.

关键词： construction land expansion change in farmland grain yield temporal and spatial variation Chinese counties

Synthesis and characterization of bifunctional terbium complex-based nanoparticles

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Chinese Science Bulletin 2012年第7期57卷 750-755页

作者： RuiHua Lu Jiang He LiZhen Huang Xia Ge XiaoYan Du Jie Zhu Lanzhou Univ State Key Lab Appl Organ Chem Lanzhou 730000 Peoples R China

Novel bifunctional terbium complex-based nanoparticles were developed using a modified Stber method and a layer-by-layer assembly process. A magnetic core of Fe3O4 nanoparticles was coated with a silica shell to form the first layer. Then a ternary Tb3+ complex (TESPPA-Tb), which acted as a luminescent marker, was covalently bound to the silica surface by stable Si-O-Si bonds. The TESPPA monomer was synthesized by binding pyridine 2,6-dicarboxylic acid to 3-aminopropyltriethoxysilane, which was used as a ligand for coordination with the Tb3+ ions. An outer shell of silica was applied to the nanoparticles to allow for versatility with surface functionalization. The nanoparticles were characterized by X-ray powder diffraction, transmission electron microscopy, Fourier transform infrared spectroscopy, ultravioletvisible spectroscopy, vibration sample magnetometer, and photoluminescence spectroscopy. The bifunctional nanoparticles exhibited favorable superparamagnetic behavior and photoluminescence properties of Tb3+. These nanoparticles have potential applications in biolabeling, bioseparation, immunoassays, and pathogenic diagnosis.

关键词：纳米粒子铽离子双功能傅立叶变换红外光谱表征合成 X-射线粉末衍射透射电子显微镜

Image segmentation based on differential immune clone clustering algorithm

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International Journal of Intelligent Computing and Cybernetics 2013年第1期6卷 83-102页

作者： Wenping Ma Feifei Ti Congling Li Licheng Jiao key lab of Intelligent Perception and Image Understanding of Ministry of Education of China Xidian UniversityXi’anChina

Purpose–The purpose of this paper is to present a Differential Immune Clone Clustering Algorithm(DICCA)to solve image ***/methodology/approach–DICCA combines immune clone selection and differential evolution,and two populations are used in the evolutionary *** reproduction and selection,differential mutation,crossover and selection are adopted to evolve two populations,which can increase population diversity and avoid local *** extracting the texture features of an image and encoding them with real numbers,DICCA is used to partition these features,and the final segmentation result is ***–This approach is applied to segment all sorts of images into homogeneous regions,including artificial synthetic texture images,natural images and remote sensing images,and the experimental results show the effectiveness of the proposed ***/value–The method presented in this paper represents a new approach to solving clustering *** novel method applies the idea two populations are used in the evolutionary *** proposed clustering algorithm is shown to be effective in solving image segmentation.

关键词： Differential evolution Clone selection Clustering Image segmentation Image processing Cluster analysis

Current status of bacteriological parameters and DOC/POC in Xiamen coastal waters

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Acta Oceanologica Sinica 2003年第3期22卷 443-451页

作者： Khalid Maskaoui, Tianling Zheng , Huasheng Hong Zhiming Yu, Zhong Hu, Yun Tian, Lizhe Cai School of Life Sciences, Xiamen University, Xiamen 361005, Chinakey laboratory of Marine Environmental Science of SED, Xiamen 361005, Chinakey laboratory of Marine Ecology & Environmental Science, Chinese Academy of Sciences, Qingdao 266071, China + Corresponding author:86-592-2183217,Fax:86-592-2181510. E-mail: wshwzh @ jingxian. xmu. edu. cn Xiamen Univ Sch Life Sci Xiamen 361005 Peoples R China SED Key Lab Martine Environm Sci Xiamen 361005 Peoples R China Chinese Acad Sci Key Lab Marine Ecol & Environm Sci Qingdao 266071 Peoples R China

The surface and bottom waters samples were collected from six locations in Xiamen western sea. The quantified estimation of bacterial production (H-3-thymidine method) and observation of bacterial heterotrophic activity (C-14-glucose method) have been made in order to have a better understanding of the role of marine bacteria and their activities. The results showed that the mean value of bacterial heterotrophic activity was 9 X 10(8) cells/(L. h) in the surface waters and 2.6 X 10(8) cells/(L. h) in the bottom waters. The mean value of bacterial production was 38 X 108 cells/( L. h) in the surface waters and 7.1 X 10(8) cells/(L. h) in the bottom waters. The relationship between bacterial production, heterotrophic activity, PCC and DOC measured during this survey were discussed. The good understanding of the relationship between bacteria activity and total coliform was addressed.

关键词： bacteriological parameters POC DOC Xiamen western sea

key Management Using Certificate-Based Cryptosystem in Ad Hoc Networks

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Journal of Shanghai Jiaotong university(Science) 2006年第2期11卷 152-157页

作者：李发根高军涛刘双根胡予濮 key lab. of Computer Networks and Information Security Xidian Univ. Xi'an 710071 China

This paper proposed a distributed key management approach by using the recently developed concepts of certificate-based cryptosystem and threshold secret sharing schemes. Without any assumption of prefixed trust relationship between nodes, the ad hoc network works in a self-organizing way to provide the key generation and key management services using threshold secret sharing schemes, which effectively solves the problem of single point of failure. The proposed approach combines the best aspects of identity-based key management approaches (implicit certification) and traditional public key infrastructure approaches (no key escrow).

关键词： ad hoc network network security key management certificate-based cryptosystem

Active probing based Internet service fault management in uncertain and noisy environment

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Science in China(Series F) 2008年第11期51卷 1857-1870页

作者： CHU LingWei ZOU ShiHong CHENG ShiDuan WANG WenDong State key lab of Networking and Switching Beijing University of Posts and Telecommunications Beijing100876 China

In Internet service fault management based on active probing, uncertainty and noises will affect service fault management. In order to reduce the impact, challenges of Internet service fault management are analyzed in this paper. Bipartite Bayesian network is chosen to model the dependency relationship between faults and probes, binary symmetric channel is chosen to model noises, and a service fault management approach using active probing is proposed for such an environment. This approach is composed of two phases： fault detection and fault diagnosis. In first phase, we propose a greedy approximation probe selection algorithm （GAPSA）, which selects a minimal set of probes while remaining a high probability of fault detection. In second phase, we propose a fault diagnosis probe selection algorithm （FDPSA）, which selects probes to obtain more system information based on the symptoms observed in previous phase. To deal with dynamic fault set caused by fault recovery mechanism, we propose a hypothesis inference algorithm based on fault persistent time statistic （FPTS）. Simulation results prove the validity and efficiency of our approach.

关键词： service management fault management active probing bipartite Bayesian network binary symmetricchannel