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Scenario simulation and forecast of land use/cover in northern china

Chinese science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2,3.& HE ChunYang 3.1 college of Geographical science, Chongqing Normal university, Chongqing 400047,{3. 2 college of Resources and Environmental science, Chongqing university, Chongqing 400044,{3. 3.college of Resources science & Technology, Beijing Normal university, Beijing 100875,{3. college of Geographical science Chongqing Normal University Chongqing 400047 China college of Resources and Environmental science Chongqing University Chongqing 400044 China college of Resources science & Technology Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 3. years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

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Expression and Identification of Mutated Osteoprotegerin in Culture Cells and Larvae of Silkworm

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Acta Biochimica et Biophysica Sinica 2004年第5期36卷 331-335页

作者： Hai-Long XIAO, Yong-Feng JIN, and Yao-Zhou ZHANG1* Institute of Biochemistry, college of life sciences, Zhejiang {3., Hangzhou 3.0029, china college of life sciences, Zhejiang {3. of science & Technology, Hangzhou 3.0018, china college of life sciences Zhejiang University of Science & TechnologyHangzhou 310018China Institute of Biochemistry College of Life SciencesZhejiang UniversityHangzhou 310029China

The mutated osteoprotegerin (OPG-3.2) gene was inserted into the baculovirus transfer vector pBacPAK8, and the recombinant plasmid was co-transfected with linearized Bm-BacPAK6 virus DNA into BmN cells, then homologous recombination occurred inside the cells. The recombinant virus BmNPV-OPG- 3.2 was screened and identified by Southern blotting. The recombinant human OPG-3.2 was expressed in cultured cells and the larvae of silkworm by inoculation of recombinant virus. The expression products were run on the SDS-PAGE and their immunoreactivities were determined by Western blotting. It was found that a 42 kD recombinant protein was expressed in BmN cells and a 46 kD one in larvae respectively. The bioactivi- ties of the recombinant proteins were determined by hypocalcemic effect assay in the mice. The results showed that the recombinant proteins had a significant hypocalcemic effect on mice sera.

关键词： OPG-3.2 silkworm baculovirus expression system hypocalcemic effect

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New fossil elaterid (Coleoptera: Polyphaga: Elateridae) from Yixian Formation of western Liaoning, china

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Progress in Natural science:Materials International 2007年第10期17卷 1244-1249页

作者： Chang Huali, Ren Dong and Shih Chungkun(college of life science, Capital Normal {3., Beijing 10003., china) college of life science Capital Normal University Beijing 100037 China

A new species of the elaterid genus Cryptocoelus Dolin and Nel, 2002 from the Late Jurassic to Early Cretaceous Yixian Formation in the western Liaoning, china is described. Diagnosis of the genus is revised, and the systematic position of the genus is briefly discussed. Because the elaterids originated in the Early to Mid-Jurassic, this new material from the Late Jurassic-Early Cretaceous will enhance our understanding of the transition between ancient elaterids and extant ones, bridge the gap of cryptic relationships between the Mesozoic cupedids and elaterids, and expand our knowledge of their evolutionary history.

关键词： Elateridae new species Yixian Formation china.

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Superhard nano-multilayers and nanocomposite coatings

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Progress in Natural science:Materials International 2005年第2期15卷 2-12页

作者： BAI Xiaoming, ZHENG Weitao* and AN Tao(Department of Material science and Key Laboratory of Automobile of MOE, jilin university, changchun 13.012,{3.) Department of Material science and Key Laboratory of Automobile of MOE Jilin University Changchun 130012 China

This paper reviews the recent development of nano-multilayers and nanocomposite coatings. The hardening mechanisms and design of hard coating are discussed in details. Recent research on Ti/TiN and nitride/nitride multilayer, Ti-Si-N and Ti-Al-Si-N nanocomposite coatings is described, and the perspectives of the related research are proposed.

关键词： nano-structured materials multilayer nanocomposite hardness

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Effects of Alloying Elements on Microstructure and Erosion Resistance of Fe-C-Cr Weld Surfacing Layer

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Journal of Materials science & Technology 2003年第4期19卷 351-354页

作者： Daqian SUN, Wenquan WANG, Zhaozhi XUAN, Yue XU and Zhenfeng ZHOUSchool of Materials science and Engineering, jilin university, changchun 13.025,{3. Sch. of Mat. Sci. and Eng. Jilin Univ. Changchun 130025 China

Effects of alloying elements on microstructure and erosion resistance of Fe-C-Cr weld surfacing layer have been studied. The experimental results show that increasing C and Cr content favors improving the erosion resistance of the layer, and the excessive C and Cr result in decreasing the erosion resistance at 90 deg. erosion. That Mo, Nb or Ti improves the erosion resistance of Fe-C-Cr weld surfacing layer is mainly attributed to increasing the amount of M7C3.and forming fine NbC or TiC in austenite matrix, but the excessive Mo, Nb or Ti is unfavorable. The addition of Mo, Nb and Ti in proper combination possesses stronger effect on improving the erosion resistance and the erosion resistance (εA) of Fe-C-Cr weld surfacing layer with fine NbC, TiC and M7C3.distributing uniformly in austenite matrix obviously increases to 2.81 at 15 deg. erosion and 2.88 at 90 deg. erosion when the layer composition is 3.05C, 20.58Cr, 1.88Mo, 2.00Nb and 1.05Ti (in wt pct).

关键词： Weld surfacing layer Alloying elements Erosion resistance

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Characterizing structural variants based on graph-genotyping provides insights into pig domestication and local adaption

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Journal of Genetics and Genomics 2024年第4期51卷 394-406页

作者： Xin Li Quan Liu Chong Fu Mengxun Li changchun Li Xinyun Li Shuhong Zhao Zhuqing Zheng Key Lab of Agricultural Animal Genetics Breeding and Reproduction of Ministry of Education and Key Laboratory of Swine Genetics and Breeding of Ministry of AgricultureCollege of Animal Science and TechnologyHuazhong Agricultural UniversityWuhanHubei 430070China Institute of Agricultural Biotechnology Jingchu University of TechnologyJingmenHubei 448000China The Cooperative Innovation Center for Sustainable Pig Production WuhanHubei 430070China Hubei Hongshan Laboratory WuhanHubei 430070China

Structural variants(SVs),such as deletions(DELs)and insertions(INSs),contribute substantially to pig genetic diversity and phenotypic *** a library of SVs discovered from long-read primary assemblies and short-read sequenced genomes,we map pig genomic SVs with a graph-based method for re-genotyping SVs in 402 *** results demonstrate that those SVs harboring specific trait-associated genes may greatly shape pig domestication and local *** characterization of SVs reveals that some population-stratified SVs may alter the transcription of genes by affecting regulatory *** identify that the genotypes of two DELs(296-bp DEL,chr7:52,172,101e52,172,3.7;278-bp DEL,chr18:23.840,143.e23.840,421)located in muscle-specific enhancers are associated with the expression of target genes related to meat quality(FSD2)and muscle fiber hypertrophy(LMOD2 and WASL)in *** results highlight the role of SVs in domestic porcine evolution,and the identified candidate functional genes and SVs are valuable resources for future genomic research and breeding programs in pigs.

关键词： Pigs Structural variation Selection signatures Regulatory elements

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The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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science china(Technological sciences) 2006年第2期49卷 238-247页

作者： ZHANG Hai’ou1, QIAN Yingping1,3. WANG Guilan1 & ZHENG Qiguang2 1. School of Material science and Technology, Huazhong university of science and Technology, Wuhan 43.074,{3. 2. Institute of Laser Technology and Engineering, Huazhong university of science and Technology, Wuhan 43.074,{3. 3. Mechanical Engineering college, Hubei university of Technology, Wuhan 43.068,{3. 1. School of Material science and Technology Huazhong University of Science and Technology Wuhan 430074 China 3. Mechanical Engineering college Hubei University of Technology Wuhan 430068 China 2. Institute of Laser Technology and Engineering Huazhong University of Science and Technology Wuhan 430074 China

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

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THE (ｕ＋κ)-ORBIT OF ESSENTIALLY NORMAL OPERATORS AND COMPACT PERTURBATIONS OF STRONGLY IRREDUCIBLE OPERATORS

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Chinese Annals of Mathematics,Series B 2000年第2期21卷 237-248页

作者： JIYOUQING JIANGCHUNLAN WANGZONGYAO DepartmentofMathematics JilinUniversityChangchun130023China. DepartmentofMathematics JilinUniversityChangchun130023China. DepartmentofMathematics EastChinaUniversityofScienceandTechnologyShanghai200237＂China.

Let н be a complex, separable, infinite dimensional Hilbert space, T　ε（Ｈ）. （ｕ＋Ｋ）（T） denotes the （ｕ＋ｋ）-orbit of T, i.e., （ｕ＋ｋ）（T） = {R-1TR: R is invertible and of the form unitary plus compact}. Let be an analytic and simply connected Cauchy domain in C and n ε N. A（, n） denotes the class of operators, each of which satisfies （i） T is essentially normal; （ii） σ（T） =,　ρF（T）　∩ σ（T） = ; （iii） ind （λ-T） = -n, nul （λ-T） = 0 （λ∈Ω ）. It is proved that given T1, T2 ε A（, n） and ε > 0, there exists a compact operator K with K <ε such that T1 +Kε （ｕ＋ｋ）（T2）. This result generalizes a result of P. S. Guinand and L. Marcoux [6,15]. Furthermore, the authors give a character of the norm closure of （ｕ＋Ｋ）（T）, and prove that for each T ε A（, n）, there exists a compact （SI） perturbation of T whose norm can be arbitrarily small.

关键词： Essentially normal (u+k)-orbit Compact perturbation Spectrum Strongly irreducible operator

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Regulation of eight avr genes by hrpG and hrpX in Xanthomonas campestris pv. campestris and their role in pathogenicity

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Progress in Natural science:Materials International 2006年第12期16卷 1288-1294页

作者： XU Rongqi~ 1,3., LI Xianzhen~3. WEI Hongyu~3. JIANG Bole~2, LI Kai~3. HE Yongqiang~ 2,3., FENG Jiaxun~ 1,3.and TANG Jiliang~ 1,2 **(1. Guangxi Key Laboratory of Subtropical Bioresources Conservation and Utilization 2. The Key Laboratory of Ministry of Education for Microbial and Plant Genetic Engineering 3. college of life science and Technology, Guangxi university, Nanning 53.004, china) Guangxi Key Laboratory of Subtropical Bioresources Conservation and Utilization Guangxi University Nanning 530004 China college of life science and Technology Guangxi University Nanning 530004 China The Key Laboratory of Ministry of Education for Microbial and Plant Genetic Engineering Guangxi University Nanning 530004 China

Eight putative avirulence genes in Xanthomonas campestris pv. campestris (Xcc) strain 8004 were characterized by Tn5gusA5 mutagenesis and gene expression analysis. The virulence test of mutants on Chinese radish showed that all mutants in individual avr genes except avrBs2 mutant were not significantly different from the wild type in virulence. The avrBs2 mutant showed reduced virulence and bacterial growth in planta. Gene expression analysis using β-glucuronidase as reporter indicated that avrBs1.1,avrBs1,avrXccB,avrXccC,avrXccE1 were regulated by hrpG, whereas avrXccA1, avrXccA2 and avrBs2 were not. RT-PCR analysis showed that all hrpG-regulated genes except avrBs1 were also regulated by hrpX. In addition, it was demonstrated that avrBs1 was responsible for elicitation of a type III dependent hypersensitive reaction (HR) on nonhost plant pepper ECW-10R, and wild type Xcc 8004 was unable to cause HR on pepper ECW-20R.

关键词： Xanthomonas campestris pv. campestris avirulence gene virulence expression analysis.

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Portable fluorescence instrument for detecting membrane integrity in membrane bioreactor (MBR)

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Frontiers of Environmental science & Engineering 2024年第2期18卷 121-131页

作者： Yang Yu changchun Xin Yuxiang Liu Fei Gao Lei Zhang Hui Jia Jie Wang State Key Laboratory of Separation Membranes and Membrane Processes Tiangong UniversityTianjin 300387China School of Environmental science and Engineering Tiangong UniversityTianjin 300387China School of Environmental science and Engineering Tianjin UniversityTianjin 300072China Shenyang Academy of Environmental sciences Shenyang 110167China Cangzhou Institute of Tiangong university Tiangong UniversityCangzhou 061000China

This study proposed the design, fabrication, and assembly of membrane integrity detection instruments in membrane bioreactors (MBR) based on fluorescence spectroscopy. Based on the PARAFAC model, we found that the peak at 280/3.5 nm strengthened after membrane breakage. The peak at 3.0/43. nm reflected the sludge concentration in the MBR and reduced the influence of internal filtration effects on detection. Therefore, we determined that the dual-LED light source excitation detection system can detect tryptophan-like substances at 280 nm (T-peak) and humic acid at 3.0 nm (C-peak). T-peak was identified as the core index indicating membrane integrity. Moreover, the C-peak is the reference indicator factor for a sensitive response to changes in the sludge concentration. The portable fluorescence instrument exhibited high sensitivity and good feedback accuracy compared to particle counting and turbidity detection, where the log reduction value was greater than 3.5. This overcomes the disadvantage of false alarms in particle counters and is not affected by the position of the pump system. This portable instrument provides a flexible and highly sensitive method for the assessment of industrial membrane integrity.

关键词： Membrane integrity Fluorescence spectrum Portable instrument Membrane bioreactor

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