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science china(Technological sciences) 2009年第3期52卷 584-589页

作者： XU YePeng1 & ZHOU Ding2.1 School of science, Nanjing university of science and technology, Nanjing 2.0094, china 2.college of Civil Engineering, Nanjing university of technology, Nanjing 2.0009, china 1. School of science Nanjing University of Science and Technology Nanjing 210094 China 2. college of Civil Engineering Nanjing University of Technology Nanjing 210009 China

This paper studies the bending of simple-supported rectangular plate on point supports, line supports and elastic foundation. On the basis of three-dimensional elasticity theory, the exact expressions of the displacement functions, which satisfy the governing differential equations and the simply supported boundary conditions at four edges of the plate, are analytically derived. The reaction forces of the in- termediate supports are regarded as the unknown external forces acting on the lower surface of the plate. The unknown coefficients are then determined by the boundary conditions on the upper and lower surfaces of the plate. Comparing the numerical results obtained from the proposed method to those obtained from Kirchhoff plate theory, Mindlin plate theory and those obtained from the commer- cial finite element software ANSYS, the high accuracy of the present method has been demonstrated.

关键词： rectangular plate point support line support elastic foundation displacement stress three-dimensional elasticity solution

Protein phosphorylation is involved in the water stress-induced ABA accumulation in the roots of Malus hupehensis Rehd

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Chinese science Bulletin 2001年第10期46卷 855-858页

作者： ZHANG Dapeng, YANG Hongqiang, JIA Wensuo & HUANG Conglin1. Laboratory of Molecular Developmental Biology of Fruit Trees, china agricultural university, Beijing 100094,{2. 2. The Key Laboratory of Plant Physiology and Biochemistry of agricultural Ministry, china agricultural university, Beijing 100094,{2. Laboratory of Molecular Developmental Biology of Fruit Trees China Agricultural University Beijing China The Key Laboratory of Plant Physiology and Biochemistry of agricultural Ministry China Agricultural University Beijing China

Water stress-induced ABA accumulation plays a key role in the root to shoot communication and/or the cell to cell signaling under the soil stresses. The signaling of the water stress itself that leads to the accumulation, however, is less known. In this study, we subjected the roots of Malus hupehensis seedlings to water stress treatment and investigated the ABA accumulation in relation to protein phos-phorylation. Our results showed that ABA accumulation could be substantially triggered in 40 min and reached 4 folds in 100 min after treatment with 30% PEG 6000 (polyethylene glycol). The water stress treatment also led to a substantial enhancement of total kinase activity, assessed with histone-111 as substrate, in 15 min and a maximum enhancement in 30 min before it declined to initial level. The Ca2.-dependent kinase activity showed a similar, if not more sensitive, trend. When the roots were fed with labeled 32.-ATP, water stress enhanced the labeling of proteins, which showed a maximum labeling at

关键词： ABA (abscisic acid) water stress protein kinases Malus hupehensis Rehd.

Mine laneway 3D reconstruction based on photogrammetry

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中国有色金属学会会刊：英文版 2011年第S3期21卷 686-691页

作者： ZHANG Chun-sen college of Geomatics, Xi’an university of {2. and technology, Xi’an 710054, china college of Geomatics Xi'an University of Science and Technology Xi'an 710054 China

Aiming at the problem of 3D reconstruction for mine laneway, the technique route and step were given based on digital close range photogrammetry and traverse surveying. 3D coordinates of laneway traverse point, photogrammetric station, control strip points were obtained by electronic total station based on mine coordinate system. The feature points were extracted from the scene images. The camera was calibrated by direct linear transformation (DLT). 3D relative coordinates of the arbitrary feature points in mine laneway were calculated after feature points being matched, in which the origin of coordinate system is photogrammetric station. The 3D absolute coordinates of the feature points in mine laneway can be obtained by the combined adjustment of photogrammetry and non-photogrammetric observations and coordinate conversion. The measurable 3D model of the underground laneway terrain surface was constructed with the 3D coordinates of feature points on the image pairs obtained. The measurable 3D model of a corridor was reconstructed by the mentioned method and the experiment precision with an average standard deviation of 0.013 6 m between the 3D model and practical measure was obtained by electronic total station. The experimental resulted show the validity of the proposed approach.

关键词： digital mine mine laneway photogrammetry 3D reconstruction direct linear transformation (DLT)

Effect and mechanism of stresses on rock permeability at different scales

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science china Earth sciences 2006年第7期49卷 714-723页

作者： YIN Shangxian1 & WANG Shangxu2.1. Safety Engineering college, North china Institute of {2. and technology, Yanjiao, Beijing 101601, china 2. Key Laboratory of Geophysics Exploration, china university of Petroleum, Beijing 100083, china 1. Safety Engineering college North China Institute of Science and Technology Yanjiao Beijing 101601 China 2. Key Laboratory of Geophysics Exploration China University of Petroleum Beijing 100083 China

The effect of geo-stress fields on macroscopic hydro-geological conditions or micro-cosmic permeability of water-bearing media should follow some laws or principles. Cases study and tests show that: (1) At macro-geologic large scale, deformed and crashed rocks which were induced by geo-stress fields changing provided space for groundwater storage and flow. Groundwater adjusts water-bearing space and dilatants fractures by flowing and press transferring. Coupling of liquid and solid can be implemented for rocks and groundwater. Although tectonic fields witness several times of change and build-up in geological time, stress fields forming regional tectonic framework are coherent with seepage fields, orientation of the maximum horizontal stress demonstrates main seepage direc-tions. (2. At macro-geologic middle scale, zones of stresses changing sharply, quite low stresses, stress or shear concentration can be used to show locations and types of main fractures, zones of geo-stresses changing equably can be acted as normal base media zones of tri-porosity media. (3) At micro-geologic small scale, tri-porosity media include fractured rocks, porous rocks and capillary rocks. Investigations indicate that porosity or permeability is functions of effective stresses, and po-rosity or permeability changing rules of porous rocks with variation of effective stresses can be de-scribed as the index model, the model of power exponent functions is suitable for those of fractured rocks, the model of the second power parabola for capillary rocks. The porosity and permeability loss in fractured rocks, which are greater than that in porous rocks, are shown by calculation of effective compressive coefficient and closing pressure in cracks. The calculations can also explain the mecha-nism why porosity changes are always larger than permeability changes. It is proved by the thick wall cylinder theory that the second power parabola relation between porosity or permeability loss and effective

关键词： geo-stress fields, seepage fields, tri-porosity media, effective stresses, permeability, porosity,scale.

The Effect of Bovine IFN-α on the Immune Response in Guinea Pigs Vaccinated with DNA Vaccine of Foot-and-Mouth Disease Virus

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Acta Biochimica et Biophysica Sinica 2004年第10期36卷 701-706页

作者： Hui-Chen GUO, Zai-Xin LIU*, Shi-Qi SUN, Qing-Wen LENG1, Dong LI, Xiang-Tao LIU, and Qing-Ge XIE* Key Laboratory of animal Virology of Ministry of Agriculture, Lanzhou Veterinary Research Institute, Chinese Academy of agricultural {2.s, Lanzhou 730046, china college of animal {2. and technology, Shihezi university, Shihezi 832.03, china 1 Key Laboratory of animal Virology of Ministry of Agriculture Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Sciences college of animal {2. and technology Shihezi University

In this study, we constructed recombinant plasmid pcDNA3.1/P12.3C3D including P1, 2., 3C, 3D and part of 2. gene of FMDV and pcDNA3.1/IFN containing the gene encoding bovine IFN-α. We inoculated the DNA vaccine pcDNA3.1/P12.3C3D with or without pcDNA3.1/IFN to evaluate the effi- ciency of this DNA vaccine and the immunogenicity of DNA vaccine enhanced by the co-delivery with pcDNA3.1/IFN. After two times of vaccination with DNA vaccine, all of guinea pigs were challenged with 103 ID50 FMDV type O. Anti-FMDV antibody levels were detected by ELISA and T lymphocyte proliferation response was tested by MTT assay. The result shows that guinea pigs inoculated by pcDNA3.1/P12.3C3D alone or with pcDNA3.1/IFN generated specific antibodies and induced an FMDV-specific T lymphocyte proliferation response. FMDV challenge tests showed that one in four guinea pigs immunized by pcDNA3.1/ P12.3C3D with pcDNA3.1/IFN was protected from the FMDV serotype O infection. This result indicated that the efficiency of the DNA vaccine was enhanced by co-delivery with pcDNA3.1/IFN. However, the protection rate was considerably lower than that immunized with conventional FMD vaccine.

关键词： foot-and-mouth disease virus (FMDV) DNA vaccine IFN-α gene vaccination

A New Clustering Algorithm for Categorical Attributes

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International Journal of Minerals,Metallurgy and Materials 2000年第4期14卷 318-322页

作者： Songfeng Lu, Zhengding Lu (college of Computer science and {2., Huazhong university of science and {2., Wuhan 430074, china) college of Computer science and {2. Huazhong University of Science and Technology Wuhan 430074 China

In traditional data clustering, similarity of a cluster of objects is measured by distance between objects. Such measures are not appropriate for categorical data. A new clustering criterion to determine the similarity between points with categorical attributes is pre- sented. Furthermore, a new clustering algorithm for categorical attributes is addressed. A single scan of the dataset yields a good clus- tering, and more additional passes can be used to improve the quality further.

关键词： data mining clustering similarity Information

Migration and population genetics of the grain aphid Macrosiphum miscanti (Takahashi) in relation to the geographic distance and gene flow

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Progress in Natural science:Materials International 2005年第11期15卷 1000-1004页

作者： GUO Wei, SHEN Zuorui, LI Zhihong and GAO Lingwang (college of Agronomy and Biotechnology,{2., Beijing 100094, china) college of Agronomy and Biotechnology China Agricultural University Beijing 100094 China

The population genetics of the grain aphid Macrosiphum miscanti (Takahashi) is analyzed by microsatellite markers. Samples collected from 15 locations in china have been examined at 5 polymorphic microsatellite loci. Overall, genetic diversity displays a relation between the migration and gene flow in the grain aphid; a free and frequent gene flow is found in the eastern populations, and gene isolation occurs in the two western populations, especially Datong population and Guiyang population. The natural barriers may present an insurmountable obstacle preventing gene flow and aphid migration. However, a spatial genetic differentiation between populations is correlated with their geographical separation, indicating the geographic differentiation may play an important role in shaping the genetic structure of M. miscanti populations. In addition, most populations of grain aphids are out of Hardy-Weinberg equilibrium and there is het-erozygote deficit. Based on F statistics, the average genetic differentiation among different geographical populations is relatively low. It seems that the long distance migration of the grain aphid may enhance gene flow and decrease genetic differentiation among different populations .

关键词： Macrosiphum miscanti microsatellite gene flow migration.

Aberrant DNA methylation patterns in cultured mouse embryos

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Progress in Natural science:Materials International 2005年第12期15卷 1079-1083页

作者： HOU Jian,CUI Xiuhong,LEI Tinghua,LIU Lei,AN Xiaorong and CHEN Yongfu State Key Laboratory for Agrobiotechnology and Department of animal Physiology,{2. of Biological science,china agricultural university,Beijing 100094,china State Key Laboratory for Agrobiotechnology and Department of animal Physiology College of Biological Science China Agricultural University Beijing 100094 China

Mouse early embryos undergo genome-wide demethylation and remethylation events during pre-implantation *** methylation reprogramming is thought to be associated with development *** immunofluorescence staining with an antibody against 5-methylcytosine (MeC),we examined the genome methylation patterns of mouse embryos cultured in *** results did not show the difference in staining patterns between development-blocked two-cell embryos that cultured in vitro and the two-cell embryos that were freshly collected from the donor *** in vitro-arrested morulae displayed a strong positive staining when compared to the morulae freshly collected from the donor *** the blastocyst stage,although most embryos showed the expected methylation patterns,with highly stained inner cell mass (ICM) and weekly stained trophectoderm (TE),a proportion of embryos were dimly stained in both ICM and *** results indicated that the methylation profile of the embryos could be changed by culturing in vitro when the embryos were in the transition from morulae to blastocyst.

关键词： methylation mouse embryo 5-methylcytosine antibody

Fuzzy tolerance quotient spaces and fuzzy subsets

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science china(Information sciences) 2010年第4期53卷 704-714页

作者： ZHANG Ling1 & ZHANG Bo2.3,4* 1Computer science & technology {2., Anhui university, Anhui 2.0039, china 2.tate Key Laboratory of Intelligent technology and Systems, Beijing 100084, china 3Tsinghua National Laboratory of Information science & technology, Beijing 100084, china 4Information science & technology {2., Computer science & technology Department, Tsinghua university, Beijing 100084, china 1. Computer science & technology {2. Anhui University Anhui 230039 China2. State Key Laboratory of Intelligent Technology and Systems Beijing 100084 China3. Tsinghua National Laboratory of Information Science & Technology Beijing 100084 China4. Information Science & Technology College Computer Science & Technology Department Tsinghua University Beijing 100084 China

The structure and characteristic of fuzzy subsets are discussed by using the concepts of granulation and hierarchy in quotient space theory. First, the equivalence relation based quotient space theory is extended to the fuzzy tolerance relation. Second, the isomorphism and its discriminant of fuzzy tolerance relations are discussed. Finally, by using the fuzzy tolerance relation to define the fuzzy subset, its properties are addressed. The main results are given below: (1) several equivalent statements of fuzzy tolerance relations; (2. the definition of isomorphism of fuzzy tolerance relations; (3) the isomorphic discriminant of fuzzy tolerance relations; (4) the definition and properties of fuzzy subsets based on the fuzzy tolerance relations; and (5) the necessary and sufficient condition of the isomorphism of fuzzy subsets. These results will help us further comprehend the concepts of fuzzy tolerance relations and fuzzy subsets.

关键词： Fuzzy tolerance relation quotient space isomorphism fuzzy subset

Maschke-type theorem and Morita context over weak Hopf algebras

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science china Mathematics 2006年第5期49卷 587-598页

作者： ZHANG Liangyun college of science, Nanjing {2. university, Nanjing 2.0095, china Department of Mathematics, Nanjing university, Nanjing 2.0008, china 1. college of science Nanjing Agricultural University Nanjing 210095 China 2. Department of Mathematics Nanjing University Nanjing 210008 China

This paper gives a Maschke-type theorem over semisimple weak Hopf algebras,extends the well-known Maschke-type theorem given by Cohen and Fishman and constructs a Morita context over weak Hopf algebras.

关键词： weak Hopf algebra, smash product, Maschke-type theorem, Morita context.