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GIS-based analysis of forest degradations in Baihe Forestry Bureau,northeast China

Science China(Technological sciences) 2006年第Z1期49卷 167-176页

作者： ZHoU Li, DAI Limin , Guofan Shao, XU Dong, wang Hui & BAI Jianwei Institute of Applied Ecology, chinese academy of sciences, Shenyang 110016, China graduate university of chinese academy of sciences, Beijing 100101, China Department of Forestry and Natural Resources, purdue university, West Lafayette, IN 47907, USA Department of City Development, Jinan university, Jinan 250002, China academy of Forest Inventory and planning, State Forestry Administration, Beijing 100714, China Institute of Applied Ecology Chinese Academy of Sciences Shenyang China graduate university of chinese academy of sciences Beijing China Department of Forestry and Natural Resources Purdue University West Lafayette USA Department of City Development Jinan University Jinan China academy of Forest Inventory and planning State Forestry Administration Beijing China

Forests in the Changbai Mountains are important timber sources for economic development of the society and p.o.ide ecological services in northeast China. In order to strengthen forest resource management, this paper analyzed management-induced changes in forest structure, tree species composition and forest landscape pattern from 1987 to 2000 for Baihe Forestry Bureau in Jilin p.o.ince based on digitized forest parcel maps and forest survey data. The results suggested that the area of Mature, High-Stocking, and Close-Canopy Forests decreased by 31.4%, 55.9% and 10.7% respectively; volume of Mixed Forest, the native forest vegetation type, decreased by 17.8%;the number of patches increased tremendously but the mean patch density decreased sharply for Mature, High-Stocking, Close-Canopy, and Mixed Forests. All the changes in forest structure, species composition, and landscape pattern indicated severe degradations going on with the forests in Baihe Forestry Bureau. Because of the effect of degradation to forest services, restoring forest resources and p.o.ecting biodiversity has become urgently important. The strategies of sustainable forest management need to be worked out and implemented.

关键词： geographic information system, forest management, Changbai Mountains, forest change, forest decline.

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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 p.o.lems of packet loss in *** encoder generates several different descriptions of the source and the decoder can p.o.uce 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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Kumada chain-growth polycondensation as a universal method for synthesis of well-defined conjugated polymers

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Science China Chemistry 2010年第8期53卷 1620-1633页

作者： GENG YanHou1,HUANG Li1,2,WU Shupeng1,2 & wang FoSong1 1State Key Laboratory of polymer physics and Chemistry Changchun Institute of Applied Chemistry,chinese academy of sciences,Changchun 130022,China 2graduate university of chinese academy of sciences,Beijing 100049,China State Key Laboratory of polymer physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun China graduate university of chinese academy of sciences Beijing China

Kumada chain-growth polycondensation (KCGp) is a novel method for the synthesis of well-defined conjugated *** the Ni-catalyst can transfer in an intramolecular p.o.ess to the p.o.agating chain end,the polymerization follows chain-growth *** this newly developed method,various conjugated polymers,such as polythiophenes,poly(p-phenylene) (ppp),polypyrrole (ppy),and polyfluorene with controlled molecular weights and relatively narrow polydispersities (pDIs),have been ***,the polymerizations for poly(3-alkylthiophene)s (p3ATs),ppp,and ppy exhibited quasi-living characteristics,which allows preparing polymer brushes,fully-conjugated block copolymers,and macroinitiators and macro-reactants for the synthesis of rod-coil block *** the current review,the p.o.ress in this new area is summarized.

关键词： chain growth polycondensation conjugated polymers Kumada reaction block copolymers polymer brush

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Transient species and its p.o.erties of melatonin

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Science China Chemistry 2006年第4期49卷 308-314页

作者： ZHU Hongping1,2, ZHANG Zhaoxia1,2, ZHAo Hongwei1, wang Wenfeng1 & YAo Side1 1. Shanghai Institute of Applied physics, chinese academy of sciences, Shanghai 201800, China 2. graduate university of the chinese academy of sciences, Beijing 100049, China Shanghai Institute of Applied physics Chinese Academy of Sciences Shanghai China graduate university of the chinese academy of sciences Beijing China

The p.o.o-physical and p.o.o-chemical p.o.erties of melatonin (ML) werestudied by 266 nm laser flash p.o.olysis (LFp). ML undergoes p.o.o-ionization to p.o.uce radicalcation of ML (ML^(·+))and hydrated electrons (e_(aq)^-), while excited triplet state ~3ML~* is alsoformed during p.o.olysis. The oxidation via one electron transfer from ML to So_4^(·+) and thetriplet state of riboflavin (~3RF~*) has been also investigated and the rate constants for thep.o.ess have been determined to be 8.0x10^9 and 1.4x10^9 L·mol^(-1)·s^(-1) respectively. Theradical cation of 2,2''-azinobis(3-ethylbenzothiazoline-6-sulfonic acid)(ABTS^(·+)) scavengingcapacities of melatonin and other antioxidants are compared in this paper.

关键词： melatonin, laser flash p.o.olysis, p.o.oionization, triplet state.

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Modern microbialites and their environmental signifi-cance,Meiji reef atoll,Nansha (Spratly) Islands,South China Sea

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Science China Earth sciences 2008年第4期51卷 608-617页

作者： SHEN JianWei1 & wang Yue1,2 1 Department of Marine Geology, South China Sea Institute of oceanology Key Laboratory of Marginal Sea Geology, South China Sea Institute of oceanology and Guangzhou Institute of Geochemistry, chinese academy of sciences, Guangzhou 510301, China 2 graduate university of the chinese academy of sciences, Beijing 100049, China Department of Marine Geology South China Sea Institute of Oceanology Guangzhou China Key Laboratory of Marginal Sea Geology South China Sea Institute of Oceanology and Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate university of the chinese academy of sciences Beijing China

Meiji (Mischief) coral atoll, in Nansha (Spratly) Islands, South China Sea, consists of an annular reef rim surrounding a central lagoon. on the atoll rim there are either p.o.uberant 'motu' (small coral patch reefs on the rim of atoll) islets or lower sandy cays that contain modern microbialite deposits on the corals in pinnacles and surrounding bottoms of the atoll. Microbialites, including villiform, hairy, and thin spine growth forms, as well as gelatinous masses, mats and encrustation, developed on coral colonies and atoll rim sediments between 0 and 15 m deep-water settings. The microbialites were p.o.uced by natural populations of filamentous cyanobacteria and grew on (1) bulbous corals together with Acropora sp., (2) on massive colonies of Galaxea fascicularis, (3) on dead Montipora digitata, and (4) on dead Acropora teres, some hairy microbialite growing around broken coral branches. This study demonstrates that microbial carbonates are developed in coral reefs of South China Sea and indicates that microbial p.o.esses may be important in the construction of modern reef systems. The results have significance in the determination of nature and composition in microorganisms implied in the formation ancient microbialites, and permit evaluation of the importance of microbial deposits in mo-dern coral reefs and of 'microbialites' in biogeochemical cycles of modern coral reef systems. The re-sults also p.o.ide evidence of modern analogues for ancient microbialites in shallow-water settings, and combine with sedimentological studies of ancient microbialites to understand their controls.

关键词： Microbialite Meiji reef Nansha Island South China Sea

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Effect of rock mass structure and block size on the slope stability——physical modeling and discrete element simulation

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Science China(Technological sciences) 2005年第Z1期48卷 1-17页

作者： LI Shihai1, LIAN Zhenzhong1,2 & J. G. wang3 1. Institute of Mechanics, chinese academy of sciences, Beijing 100080, China 2. graduate School, chinese academy of sciences, Beijing 100060, China 3. Tropical Marine Science Institute, National university of Singapore, Singapore 119260 Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China graduate School Chinese Academy of Sciences Beijing 100060 China Tropical Marine Science Institute National University of Singapore Singapore 119260 Singapore

This paper studies the stability of jointed rock slopes by using our imp.o.ed three-dimensional discrete element methods (DEM) and physical modeling. Results show that the DEM can simulate all failure modes of rock slopes with different joint configurations. The stress in each rock block is not homogeneous and blocks rotate in failure development. Failure modes depend on the configuration of joints. Toppling failure is observed for the slope with straight joints and sliding failure is observed for the slope with staged joints. The DEM results are also compared with those of limit equilibrium method (LEM). Without considering the joints in rock masses, the LEM predicts much higher factor of safety than physical modeling and DEM. The failure mode and factor of safety predicted by the DEM are in good agreement with laboratory tests for any jointed rock slope.

关键词： rock masses, slope stability, DEM simulation, block size effect, joints configuration effect, limit equilibrium method.

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Antitumor Effect of a Novel Adeno-associated Virus Vector Targeting to Telomerase Activity in Tumor Cells

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Acta Biochimica et Biophysica Sinica 2004年第7期36卷 492-500页

作者： Yi-Gang wang1,2#, Jin-Hui wang1#, Yan-Hong ZHANG1, Qing GU2*, and Xin-Yuan LIU1* 1Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological sciences, chinese academy of sciences, graduate School of the chinese academy of sciences, Shanghai 200031, China School of Life Science, Nanchang university, Nanchang 330047, China Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China School of Life Science Nanchang UniversityNanchang 330047 China

Telomerase activity is a wide tumor marker. Human telomerase reverse transcriptase (hTERT), the catalytic subunit of the telomerase, is transcriptionally upregulated exclusively in about 90% of cancer cells. In this study, we constructed a novel adeno-associated virus (AAV) vector containing the human interferon-β (hIFN-β) gene under the control of hTERT p.o.oter (AAV-hTERT-hIFN-β) and investigated its antitumor effect against various human cancer cells in vitro. AAV-hTERT-hIFN-β displayed cancer-specific hIFN-β expression and cytotoxicity. The cytotoxic ratio was positively correlated with the time length of infection. AAV-hTERT-hIFN-β-mediated apop.o.ic morp.o.ogy was observed by transmission electron microscopy. Flow cytometry assay also revealed that the cytotoxicity of AAV-hTERT-hIFN-β was mainly an apop.o.ic p.o.ess. These data indicate that AAV in combination with hTERT-mediated therapeutic gene expression may open new possibilities for long-lasting and targeting gene therapy of varieties of cancers.

关键词： adeno-associated virus (AAV) telomerase hTERT p.o.oter human interferon-β cancer

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A unified dynamic model for locomotion and manipulation of a snake-like robot based on differential geometry

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Science China(Information sciences) 2011年第2期54卷 318-333页

作者： wang ZhiFeng1,3, MA ShuGen1,2, LI Bin1 & wang YueChao1 1State Key Laboratory of Robotics, Shenyang Institute of Automation, chinese academy of sciences, Shenyang 110016, China 2Department of Robotics, Ritsumeikan university, Shiga-ken 525-8577, Japan 3graduate university of chinese academy of sciences, Beijing 100039, China State Key Laboratory of Robotics Shenyang Institute of Automation Chinese Academy of Sciences Shenyang China graduate university of chinese academy of sciences Beijing China Department of Robotics Ritsumeikan University Shiga-ken Japan

A snake-like robot, whose body is a seried-wound articulated mechanism, can move in various environments. In addition, when one end is fixed on a base, the robot can manipulate objects. A method of dynamic modeling for locomotion and manipulation of the snake-like robot is developed in order to unify the dynamic equations of two states. The transformation from locomotion to manipulation is a mechanism reconfiguration, that is, the robot in locomotion has not a fixed base, but it in manipulation has one. First, a virtual structure method unifies the two states in mechanism (e.g., an embedding in the configuration space); second, the p.o.uct-of-exponentials formula describes the kinematics; third, the dynamics of locomotion and manipulation are established in a Riemannian manifold; finally, based on the analysis of the dynamic model, the dynamics of manipulation can be directly degenerated from those of locomotion, and this degeneration relation is p.o.ed through using the Gauss equations. In the differential geometry formulation, this method realizes the unification of the dynamics of locomotion and manipulation. According to a geometrical point of view, the unified dynamic model for locomotion and manipulation is considered as a submanifold p.o.lem endowed with geometric meaning. In addition, the unified model offers an insight into the dynamics of the snake-like robot beyond the dynamic model separately established for locomotion or manipulation.

关键词： snake-like robot dynamics unified model differential geometry locomotion manipulation

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Confirmation of a natural hybrid species in petrocosmea(Gesneriaceae) based on molecular and morp.o.ogical evidence

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Journal of Systematics and Evolution 2011年第5期49卷 449-463页

作者： 1,3~Zhi-Jing QIU 2~Zu-Li YUAN 1~Zhen-Yu LI 1~Yin-Zheng wang 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of sciences,Beijing 100093,China) 2(Henan Agricultural university,Zhengzhou 45002,China) 3(graduate School of the chinese academy of sciences,Beijing 100049,China) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate School of the chinese academy of sciences Beijing 100049 China) (Henan Agricultural university Zhengzhou 45002 China)

A natural hybrid species in petrocosmea named Longianthera in Yanshan County,Yunnan p.o.ince is confirmed for the first time based on molecular and morp.o.ogical *** character count p.o.edure of the variable characters show that Longianthera populations are characteristic of the intermediate morp.o.ogical traits between its putative parents Yanshan and petrocosmea *** nuclear ribosomal internal transcribed spacer region and three chloroplast regions of matK,trnL-F,and trnT-L are sequenced in the putative hybrid and the related *** alignment of DNA sequences and the phylogenetic trees could exclude all the other species in petrocosmea as the parental species except for Yanshan and *** hap.o.ypes in the 31 internal transcribed spacer sequences and six hap.o.ypes in 42 cpDNA sequences were found from 14 individuals of Longianthera *** analyses of DNA sequences,hap.o.ypes,and phylogenetic trees indicate that Longianthera is likely a hybrid species between its putative parents Yanshan and ***,in which Yanshan might be the most possible maternal *** factors may contribute to the natural hybridization between these two parental species in petrocosmea,such as the overlapped geographic distribution,habitats,flowering periods,and shared ***,the new species of Yanshan and the natural hybrid species of Longianthera are described.

关键词： chloroplast DNA Gesneriaceae ITS morp.o.ogy natural hybridization petrocosmea.

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GIS-Based Assessment of Land Suitability for optimal Allocation in the Qinling Mountains, China

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pedosphere 2006年第5期16卷 579-586页

作者： LIU Yan-Sui wang Jie-Yong GUo Li-Ying Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 （China） graduate School of chinese academy of sciences Beijing 100039 （China） College of Tourism and Environmental sciences Shaanxi Normal University Xi＇an 710062 （China）

A GIS-based method was used to assess land suitability in the Qinling Mountains, Shaanxi p.o.ince of China through simultaneous consideration of physical features and current land use. Through interpretation of Landsat TM images and extensive field visits the area was modeled into 40 land types in five altitudinal zones (valleys and gullies, hillsides and terraces, foothills, mid-mountain, and sub-alpine mountain). Then, a suitability score was assigned to five physical factors (climate, hydrology, topography, soil, and vegetation). Next, their integrated overall suitability value scores were compared with the observed land cover to determine whether it should be reallocated a new use. Results showed that the five suitability classes of agriculture, forest, grassland, farmland-woodland, and scrub-pasture had altitudinal stratification and a total of 1151 km2 (8.89%) of lands on the northern slopes of the Qinling Mountains had to be reallocated. To achieve this reallocation, 657 km2 of arable land should be reduced, and forest, grassland and scrub-pasture increased by 615 km2, 131 km2 and 405 km2, respectively. Implementation of these recommended land reallocations should help achieve suitable use of land resources and prevent land degradation.

关键词： GIS landforms optimal allocation Qinling Mountains suitability evaluation

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