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Relationships between bacterial-algal proliferating and mass extinction in the Late Devonian Frasnian-Famennian transition:Enlightening from carbon isotopes and molecular fossils

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science china Earth sciences 2005年第10期48卷 1656-1665页

作者： GONG Yiming1,2, XU Ran1, TANG Zhongdao1, SI Yuanlan3.& LI Baohua4.1. Faculty of Earth science and State Key Laboratory of Geological Processes and Mineral Resources, china university of Geosciences, Wuhan 4.0}074. china 2. Institute of Resources & Environments, Henan Polytechnic university, Jiaozuo 4.4.03. china 3. department of computer science, south-central university for nationalities, Wuhan 4.0}074. china 4. Laboratory of Marine Geology, Tongji university, Shanghai 200092, china Faculty of Earth science and State Key Laboratory of Geological Processes and Mineral Resources china university of Geosciences Wuhan china Institute of Resources & Environments Henan Polytechnic university Jiaozuo china department of computer science{3. Wuhan{4. Laboratory of Marine Geology Tongji university Shanghai china

Studies show positive shifts of inorganic and organic carbon isotope values (δ 13.carb and δ 13.kerogen) from +0.4.0}(‰ V-PDB) to +3.54.(‰ V-PDB) and from ?29.3. (‰ V-PDB) to ?24.14.(‰ V-PDB), respectively, B* (Ba* = Ba/ (Al2O3.X 15%)) values from 0.015 to 0.14., TOC values from 0.02% to 0.21%, V/Cr values from 0.3.to 2.0, Sr/Ba values from 3.20 to 4..50 in the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone of the Yangdi sec-tion deposited in carbonate slope facies of Guilin, Guangxi, south china, which indicates that biomass, productivity, organic carbon burial and salinity increase and that oxygenation near the boundary between sediments and waters decreases from the Late Devonian Frasnian Upper rhenana zone to the top linguiformis zone. Abundance of molecular fossils increases and normal alkanes, isoprenoid hydrocarbon, terpanes and steranes are dominated from the Late Devonian Frasnian to the bottom of Famennian, which shows that the predecessors of molecular fossils of the Frasnian-Famennian (F-F) transition are dominated by marine phytoplankton, zooplankton and benthic bacteria with no photosynthesis. Therefore, it is considered that the F-F transitional mass extinction with a multistage, selection and global synchronizing was caused by bacte-rial-algal proliferating, continuing deterioration of the shallow marine ecoenvironment of the mid-dle-lower latitudes. A simple cause and effect chain can be expressed as: appearance of seed plants and multi-storied forests → enhanced chemical and biochemical weathering and pe-dogenesis → wide development of soils → increasing riverine nutrient fluxes in epicontinental sea → from superoligotrophic to eutrophic in epicontinental sea → proliferating of marine phyto-plankton and zooplankton → frequent red tide and anoxia → mass extinction of shallow marine organisms in the middle-lower latitudes. It is worth notice that the factor drawdown of atmos-pheric Pco2, climatic cooling and sea level falling c

关键词： mass extinction, bacteria-algae, carbon isotopes, molecular fossils, biodiversity, Late Devonian, Guangxi, south china.

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A Feedback-Based Web Search Engine

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Wuhan university Journal of Natural sciences 2004年第5期9卷 561-568页

作者： ZHANG Wei-feng 1,2,3., XU Bao-wen 2,3.4., ZHOU Xiao-yu 2,3.4.1. department of {4. science and Engineering, Nanjing {3. of Posts and Telecommunications, Nanjing 210003. Jiangsu,{4. 2. department of {4. science and Engineering, southeast {3., Nanjing 210096, Jiangsu,{4. 3. Jiangsu Institute of Software Quality, Nanjing 210096 Jiangsu,{4. 4. The State Key Laboratory of Software Engineering, Wuhan {3., Wuhan 4.0}072, Hubei,{4. department of computer science and Engineering Nanjing University of Posts and Telecommunications . Nanjing 210003 Jiangsu China

Web search engines are very useful information service tools in the Internet. The current web search engines produce search results relating to the search terms and the actual information collected by them. Since the selections of the search results cannot affect the future ones, they may not cover most people’s interests. In this paper, feedback information produced by the user’s accessing lists will be represented by the rough set and can reconstruct the query string and influence the search results. And thus the search engines can provide self-adaptability. Key words WWW - search engine - query reconstruction - feedback CLC number TP 3.1. 13..4.Foundation item: Supported by the National Natural science Fundation of china (603.3.66). National Grand Fundamental Research 973.Program of china (2002CB3.200). Opening Foundation of State Key Laboratory of Software Engineering in Wuhan {3., Opening Foundation of Jiangsu Key Laboratory of {4. Information Processing Technology in Soochow {3.Biography: ZHANG Wei-feng (1975-), male, Ph.D. research direction: artificial intelligence, search engine, data mining, network language.

关键词： WWW search engine query reconstruction feedback

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The construction of infinite families of any k-tight optimal and singular k-tight optimal directed double loop networks

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science china Mathematics 2007年第7期50卷 1055-1064页

作者： Bao-xing CHEN~(1+) Xie-bin CHEN~2 Ji-xiang MENG~3.Wen-jun XIAO~4.1 department of computer science,Zhangzhou Teachers College,Zhangzhou 3.3.00,{3. 2 department of Mathematics and Information science,Zhangzhou Teachers College,Zhangzhou 3.3.00,{3. 3.College of Mathematics & System science,Xinjiang {14.,Urumqi 83.04.,{3. 4.department of computer science,{13. china {14. of Technology,Guangzhou 51064.,{3. 1. department of computer science Zhangzhou Teachers College Zhangzhou 363000 China 2. department of Mathematics and Information science Zhangzhou Teachers College Zhangzhou 363000 China 3. College of Mathematics & System science Xinjiang University Urumqi 830046 China 4. department of computer science South China University of Technology Guangzhou 510641 China

The double loop network(DLN)is a circulant digraph with n nodes and outdegree *** is an important topological structure of computer interconnection networks and has been widely used in the designing of local area networks and distributed *** the number n of nodes,how to construct a DLN which has minimum diameter?This problem has attracted great attention.A related and longtime unsolved problem is:for any given non-negative integer k,is there an infinite family of k-tight optimal DLN?In this paper,two main results are obtained:(1)for any k≥0,the infinite families of k-tight optimal DLN can be constructed,where the number n(k,e,c)of their nodes is a polynomial of degree 2 in e with integral coefficients containing a parameter c.(2)for any k≥0, an infinite family of singular k-tight optimal DLN can be constructed.

关键词： double loop network diameter k-tight optimal singular k-tight optimal 05C12 05C20 05C85

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Material basis for inhibition of Dragon's Blood on evoked discharges of wide dynamic range neurons in spinal dorsal horn of rats

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science china(Life sciences) 2008年第11期51卷 1025-1038页

作者： GUO Min, CHEN Su & LIU XiangMing department of Biological & Medical Engineering, south-central university for nationalities, Wuhan 4.2}074. china 1. department of Biological & Medical Engineering South-Central University for Nationalities Wuhan 430074 China

In vivo experiments were designed to verify the analgesic effect of Dragon’s Blood and the material basis for this effect. Extracellular microelectrode recordings were used to observe the effects of Dragon’s Blood and various combinations of the three components (cochinchinenin A, cochinchinenin B, and loureirin B) extracted from Dragon’s Blood on the discharge activities of wide dynamic range (WDR) neurons in spinal dorsal horn (SDH) of intact male Wistar rats evoked by electric stimulation at sciatic nerve. When the Hill's coefficients describing the dose-response relations of drugs were dif-ferent, based on the concept of dose equivalence, the equations of additivity surfaces which can be applied to assess the interaction between three drugs were derived. Adopting the equations and Tal-larida's isobole equations used to assess the interaction between two drugs with dissimilar dose-response relations, the effects produced by various combinations of the three components in modulating the evoked discharge activities of WDR neurons were evaluated. Results showed that Dragon’s Blood and its three components could inhibit the evoked discharge frequencies of WDR neurons in a concentration-dependent way. The Hill's coefficients describing dose-response relations of three components were different. Only the combined effect of cochinchinenin A, cochinchinenin B and loureirin B was similar to that of Dragons Blood. Furthermore, the combined effect was synergistic. This investigation demonstrated that through the synergistic interaction of the three components Dragon’s Blood could interfere with the transmission and processing of pain signals in spinal dorsal horn. All these further proved that the combination of cochinchinenin A, cochinchinenin B, and loureirin B was the material basis for the analgesic effect of Dragon’s Blood.

关键词： Dragon’s Blood material basis for the efficacy extracellular microelectrode recordings wide dynamic range neurons interaction between drugs

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Mining and Integrating Reliable Decision Rules for Imbalanced Cancer Gene Expression Data Sets

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Tsinghua science and Technology 2012年第6期17卷 666-673页

作者： Hualong Yu 1 , Jun Ni 2 , Yuanyuan Dan 3., Sen Xu 4.1. School of computer science and Engineering, Jiangsu university of science and Technology, Zhenjiang 212003.{4. 2. department of Radiology, Carver College of Medicine, The university of Iowa, Iowa City, IA 5224., USA 3. School of Biology and Chemical Engineering, Jiangsu university of science and Technology, Zhenjiang 212003.{4. 4. School of Information Engineering, Yancheng Institute of Technology, Yancheng 224.51,{4. School of computer science and Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China|c|

There have been many skewed cancer gene expression datasets in the post-genomic era. Extraction of differential expression genes or construction of decision rules using these skewed datasets by traditional algorithms will seriously underestimate the performance of the minority class, leading to inaccurate diagnosis in clinical trails. This paper presents a skewed gene selection algorithm that introduces a weighted metric into the gene selection procedure. The extracted genes are paired as decision rules to distinguish both classes, with these decision rules then integrated into an ensemble learning framework by majority voting to recognize test examples; thus avoiding tedious data normalization and classifier construction. The mining and integrating of a few reliable decision rules gave higher or at least comparable classification performance than many traditional class imbalance learning algorithms on four benchmark imbalanced cancer gene expression datasets.

关键词： cancer gene expression data class imbalance paired differential expression genes decision ruleensemble learning majority voting

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Kernel model-based diagnosis

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Progress in Natural science:Materials International 2002年第2期12卷 63-67页

作者： OUYANG Dantong(department of computer science, Jilin {3., Changchun 13.012,{4.) Jilin Univ Dept Comp Sci Changchun 130012 Peoples R China

The methods for computing the kernel consistency-based diagnoses and the kernel abductive diagnoses are only suited for the situation where part of the fault behavioral modes of the components are known. The characterization of the kernel model-based diagnosis based on the general causal theory is proposed, which can break through the limitation of the above methods when all behavioral modes of each component are known. Using this method, when observation subsets deduced logically are respectively assigned to the empty or the whole observation set, the kernel consistency-based diagnoses and the kernel abductive diagnoses can deal with all situations. The direct relationship between this diagnostic procedure and the prime implicants/implicates is proved, thus linking theoretical result with implementation.

关键词： model-based diagnosis general causal theory prime implicant/implicate diagnostic space.

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ENTITY-ROLES MODEL AND OBJECT-ORIENTED KNOWLEDGE/DATA BASES

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Journal of central south university 1994年第1期6卷 74-77页

作者： Pan Jiuhui Liu Zhimin Wang Yunyi(department of computer science, {3. {4. university of Technology, Changsha, 4.0083. china) 1. department of computer science Central South University of Technology 410083 Changsha China

A Model, called 'Entity-Roles' is proposed in this paper in which the world of Interest is viewed as some mathematical structure. With respect to this structure, a First order (three-valued) Logic Language is *** world to be modelled can be logically specified in this Language. The integrity constraints on the database and the deducing rules within the Database world are derived from the proper axioms of the world being modelled.

关键词： expert systems data model object-orientation database logic deductive query

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Up-conversion emissions of Er^(3.)-Yb^(3.) codoped Al_2O_3.nanoparticles by the arc discharge synthesis method

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science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 1043-1046页

作者： DONG Bin1, CAO BaoSheng1, FENG ZhiQing1, WANG XingJun2, LI ChengRen3.& HUA RuiNian4.1 School of science, Dalian nationalities university, Dalian 116600,{3. 2 School of Electronics Engineering and {4. science, Peking university, Beijing 100871,{3. 3.College of Physics and Electronic Technology, Liaoning Normal university, Dalian 116029,{3. 4.College of Life science, Dalian nationalities university, Dalian 116600,{3. 1. School of science Dalian Nationalities University Dalian 116600 China 2. School of Electronics Engineering and computer science Peking University Beijing 100871 China 3. College of Physics and Electronic Technology Liaoning Normal University Dalian 116029 China 4. College of Life science Dalian Nationalities University Dalian 116600 China

The Er3.-Yb3. codoped Al2O3.nanoparticles with an average particle size of about 50 nm have been synthesized by an arc discharge synthesis method. The green and red up-conversion emissions centered at about 526, 54. and 677 nm, corresponding respectively to the 2H11/2→4.15/2, 4.3.2→4.15/2 and 4.F9/2→4.15/2 transitions of Er3., were detected by a 978-nm semiconductor laser diode excitation. The Annealing has evident effect on the up-conversion emissions of the samples: The red up-conversion emission is noticeable before annealing; however, the green up-conversion emission becomes predominant after annealing. The mixture of (Er,Yb)3.l5O12 and α-(Al,Er,Yb)2O3.phases is more favorable for green up-conversion emissions due to an enhancement of the ESA (I) of 4.11/2+a photon→4.7/2 and ET (III) of 2F5/2(Yb3.)+4.11/2(Er3.)→2F7/2(Yb3.)+4.7/2(Er3.) processes. The two-photon absorption up-conversion process is involved in the green and red up-conversion emissions. The results have proved that arc discharge synthesis is a new promising preparation technology for optical materials.

关键词： up-conversion Er3.-Yb3. codoped Al2O3 arc discharge synthesis

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Singular Integral Equations with Cosecant Kernel in Solutions with Singularities of High Order

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Wuhan university Journal of Natural sciences 2005年第2期10卷 339-343页

作者： HAN Hui-li 1,2 ,DU Jin-yuan 1,3.1. School of Mathematics and Statistics, Wuhan university, Wuhan 4.0}072, Hubei, china 2. School of Mathematics and {4., Ningxia university, Yinchuan 750021, Ningxia, china 3. department of Mathematics, Hubei Institute for nationalities, Enshi 4.5000, Hubei, china Wuhan university School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Ningxia university School of Mathematics and Computer Yinchuan Ningxia China (GRID:grid.260987.2) (ISNI:***) Wuhan university School of Mathematics and Statistics Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***) Hubei Institute for nationalities Department of Mathematies Enshi Hubei China (GRID:grid.34418.3a) (ISNI:***)

We have discussed and solved the boundary value problem with period 2aπ and the singular integral equation with kernel csc t-tv/a in solution having singularities of high order, where the smooth contour of integratio... 详细信息

关键词： boundary value problem singular integral equation the singularities of high order

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Nontrivial homoclinic orbits for second-order singular and periodic Hamiltonian systems

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Chinese science Bulletin 1999年第2期44卷 123-129页

作者： LI Chengyue , FAN Tianyou TONG MingshengResearch Center of Materials science, Beijing Institute of Technology, Beijing 100081, china department of Mathematics, {3. {4. for nationalities, Beijing 100081, china computer Center, Beijing Institute of Technology, Beijing 100081, china Research Center of Materials science Beijing Institute of Technology Beijing China department of Mathematics Central University for Nationalities Beijing China computer Center Beijing Institute of Technology Beijing China

The existence of nontrivial homoclinic orbits of periodic Hamiltonian systems: is proved, where q=（q1,q2,’',qn）, n>2; V（t, q）:R1×Rn\{e}→R1 is a potential With a singularity, i.e. -V（t, q）→+∞, as q→e. The m... 详细信息

关键词： Hamiltonian systems strong force condition homoclinic orbit.

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