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Some geometric properties of successive difference substitutions

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science china(Information sciences) 2011年第4期54卷 778-786页

作者： HOU XiaoRong 1,XU Song 1,2 & SHAO JunWei 1 1 School of Automation Engineering,university of Electronic science and technology of china,Chengdu 611731,china 2 faculty of science,Ningbo university,Ningbo 315211,china 1. School of Automation Engineering University of Electronic Science and Technology of China Chengdu 611731 China2. Faculty of Science Ningbo University Ningbo 315211 China

This paper provides a new,geometric perspective to study successive difference substitutions,and proves that the sequence of the successive difference substitution sets is not *** interesting result that a given k-dimensional rational hyperplane can be transformed to a k-dimensional coordinate hyperplane of new variables by finite steps of successive difference substitutions is ***,a sufficient condition for the sequence of the successive difference substitution sets of a form being not terminating is *** is,a class of polynomials which cannot be proved to be positive semi-definite by the successive difference substitution method are obtained.

关键词： successive difference substitutions nonnegativity decision of forms Barycentric subdivision

Production of porcine cloned transgenic embryos expressing green fluorescent protein by somatic cell nuclear transfer

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science china(Life sciences) 2006年第2期49卷 164-171页

作者： ZHANG Yunhai1, PAN Dengke1,2, SUN Xiuzhu1, SUN Guojie1, WANG Xiaobo1, LIU Xiaohui1, LI Yan1, DAI Yunping1 & LI Ning1 1. State Key Laboratory for Agrobiotechnology, china agricultural university, Beijing 100094, china 2. College of animal science and technology, china agricultural university, Beijing 100094, china State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China College of animal science technology China Agricultural University Beijing 100094 China

In the present study, nuclear transferred embryos (NTEs) were reconstructed by using pig fetal fibroblasts as donors; in vitro matured oocytes as recipients. The effects of G418 selection on donor cells, duration of IVM of prepubertal gilt oocytes; oxygen tension in IVM of oocytes were investigated. The results were as follows: (i) When G418 selected cells expressing GFP were used as donors, the cleavage rate of NTEs decreased drastically in comparison to NTEs derived from donors without antibiotic selection (47.5% vs. 71.6%, p>0.05). For the blastocyst rate, no significant difference was observed between two groups (10% vs. 10.4%, p2 h (83.6% vs. 96.7%, p>0.05). However, no statistical difference was observed between NTEs derived from oocytes of 36 h IVM group; NTEs from oocytes of 42 h IVM group in the rates of cleavage (59.3% vs. 73.6%, p2%, p2) tension; NTEs derived from oocytes matured under higher oxygen tension (20% O2) in cleavage rate (70.6% vs. 67.1%, p2.3%, p2 h, while no significant differences were observed for developmental potential of transgenic embryos. Thus IVM 42 h is the better choice in order to obtain maximum number of MII oocytes as recipients. (iii) Lower oxygen tension; higher oxygen tension in IVM have no significant effect on development of cloned embryos.

关键词： transgenic cloning, GFP, Pig, early development.

A mathematical model for concept granular computing systems

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science china(Information sciences) 2010年第7期53卷 1397-1408页

作者： QIU GuoFang1, MA JianMin2, YANG HongZhi3 & ZHANG WenXiu3 1School of Management, Xi’an university of Architecture & technology, Xi’an 710055, china 2faculty of science, Chang’an university, Xi’an 710064, china 3faculty of science, Xi’an Jiaotong university, Xi’an 710049, china 1. School of Management Xi’an University of Architecture & Technology Xi’an 710055 China2. Faculty of Science Chang’an University Xi’an 710064 China3. Faculty of Science Xi’an Jiaotong University Xi’an 710049 China

Extent-intent and intent-extent operators are introduced between two complete lattices in this paper and a mathematical model for concept granular computing system is established. We proved that the set of all concepts in this system is a lattice with the greatest element and the least element. This framework includes formal concept lattices from formal contexts, L fuzzy concept lattices from L fuzzy formal contexts and three kinds of variable threshold concept lattices, i.e. the extension and the intension of a concept are a crisp set and a crisp set, a crisp set and a fuzzy set, a fuzzy set and a crisp set, respectively. Finally, some iterative algorithms for constructing concepts are proposed and they are proved to be optimal concepts under some conditions in this system.

关键词： granular computing formal concept analysis concept lattice mathematical model

The Information Integration of CAPP in CIMS

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厦门大学学报（自然科学版） 2002年第S1期41卷 182-183页

作者： ZHANG Yu 1, XIONG Man-chen 2 (CIMS Application and Research Center, faculty of Mechanical and Electr onic Engineering, kunming university of science and technology, kunming 65009 3, china)

This paper analyzes the flow of the process design an d the fountain of the technique data in a manufacturing enterprise, and discusse s the information flows between CAPP and other systems in CIMS, such as CAD syst em and Enterprise Resource Planning (ERP) system. And then, it discusses the pla ns of information integration between CAPP and CAD, as well as between CAPP and ERP. To design the processes of a product requires the manufacture information, such as blank material and machine tool, which is saved in a database in ERP. General ly, a traditional CAPP system considers the information of the manufacturing res ources, such as machine tool, as changeless. However, it is real changing, becau se the resources may be occupied or the machine tool may be under repair. Theref ore, in order to design the processes more reasonably, we must consider the real change of resources in a workshop. Creating a public resource database to suppo rt the real change of resources is put forward in this paper. With the public re source database, the resource integration between CAPP system and ERP is realize d; and by information collections in CAPP system, such as BOM, the material cons umption and man-hour consumption and their output to ERP, the information integ ration between CAPP system and ERP is realized.

关键词： CIMS CAPP ERP information integration techniq ue data

Phototoxic effect of UVR on wild type, ebony and yellow mutants of Drosophila melanogaster: Life Span, fertility, courtship and biochemical aspects

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science china(Life sciences) 2008年第10期51卷 885-893页

作者： WANG ZhePeng1,2, LIU RuiFang2, WANG AnRu3, DU LiLi1 & DENG XueMei1 1 College of animal science and technology, china agricultural university, Beijing 100094, china 2 Vocational and Technologic College, Inner Mongolia Agriculture university, Baotou 014109, china 3 College of Veterinary Medicine, china agricultural university, Beijing 100094, china 1. College of animal science and technology China Agricultural University Beijing 100094 China 2. Vocational and Technologic College Inner Mongolia Agriculture University Baotou 014109 China 3. College of Veterinary Medicine China Agricultural University Beijing 100094 China

Melanin plays an important role in protecting organisms from ultraviolet radiation (UVR). Therefore, it is possible that differently colored strains can show different sensitivities to UVR. In the present work, life span, fertility and courtship behavior of wild type (w), ebony (e) and yellow (y) strains of Drosophila melanogaster were studied to evaluate their sensitivity to ultraviolet (UV). Because a range of photo- toxic effects of UVR are mediated through generation of free radicals, levels of free radicals, lipid per- oxide (malondialdehyde, MDA) and superoxide dismutase (SOD) activity of three strains were examined to indicate their antioxidant defending ability and oxidative status. It was shown that w always had the highest lifespan and fertility not only in the control but also in UV-exposed groups. Moreover, lifespan and fertility of e were significantly higher (P2) effect on the SOD activities. After pooling data from the control and UV-exposed groups, we found that w had a significantly (P0.05). MDA levels were increased in the UV dose-dependent manner (P=0.0495). In con- clusion, our results suggested that UVR can decrease life span and fertility of flies and do harm to courtship, which may be due to oxidative damage to flies tissues (e.g. central nervous system) induced by free radicals. w had the highest tolerance to UVR, which may be ascribed to its advantage of survival under the natural condition and at high level of SOD activity. Then differences of pigment between e and y in absorbing UV, shielding agai

关键词： ultraviolet radiation Drosophila melanogaste free radicals pigment

Electronic structure of O-doped SiGe calculated by DFT+U method

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Chinese Physics B 2016年第12期25卷 377-389页

作者：赵宗彦杨雯杨培志 faculty of Materials science and Engineering Kunming University of Science and Technology yunnan Key Laboratory of Micro/Nano Materials & technology School of Materials Science and EngineeringYunnan University Key Laboratory of Advanced Technique & Preparation for Renewable Energy Materials (Ministry of Education) Yunnan Normal University

To more in depth understand the doping effects of oxygen on SiGe alloys, both the micro-structure and properties of O-doped SiGe （including： bulk, （001） surface, and （110） surface） are calculated by DPT ＋ U method in the present work. The calculated results are as follows. （i） The （110） surface is the main exposing surface of SiGe, in which O impurity prefers to occupy the surface vacancy sites. （ii） For O interstitial doping on SiGe （110） surface, the existences of energy states caused by 0 doping in the band gap not only enhance the infrared light absorption, but also improve the behaviors of photo-generated carriers. （iii） The finding about decreased surface work function of O-doped SiGe （110） surface can confirm previous experimental observations. （iv） In all cases, O doing mainly induces the electronic structures near the band gap to vary, but is not directly involved in these variations. Therefore, these findings in the present work not only can provide further explanation and analysis for the corresponding underlying mechanism for some of the experimental findings reported in the literature, but also conduce to the development of μc-SiGe-based solar ceils in the future.

关键词： SiGe alloys 0 doping electronic structure density functional theory (DFT) calculations

Analysis of the Resistance Gene Analogue for Rice Cultivars in yunnan Province

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agricultural sciences in china 2002年第5期1卷 549-554页

作者： SUN Yan, WANG Yun-yue, HE Yue-qiu, FAN Jing-hua, CHEN Jian-bin and ZHU You-yong( Key Laboratory for Plant Pathology of yunnan Province ,yunnan agricultural university, kunming 650201 ,P.R. china College of Agronomy and Biotechnology , yunnan agricultural university , kunming 650201 , P. R . china ) Key Laboratory for Plant Pathology of yunnan Province Yunnan Agricultural University Kunming 650201 P. R. China College of Agronomy and Biotechnology Yunnan Agricultural University Kunming 650201 P. R. China Key Laboratory for Plant Pathology of yunnan Province Yunnan Agricultural University Kunming 650201 P. R. China

Genetic diversity of commercial and local rice cultivars in yunnan Province was studied using the resistance gene analogue (RGA) based on resistance gene conserved sequences. The RGA analysis of 137 cultivars was conducted by PCR amplification using three primers, i.e. S1/AS3, XLRR for/XLRR rev, and Pto-kinl/Pto-kin2, respectively. The results showed that both Indica and Japonica cultivars were genetically highly diverse. All cultivars were divided into 3 lineages according to the DNA band data at 96% dissimilarity, and into 20 lineages at 60% dissimilarity. The lineages were related to their genetic background and blast disease resistance with only a few exceptions. The RGA data can be useful in rice production by mixed-planting of different cultivars in the field and breeding of resistance cultivars by selecting different parental cultivars with great genetic diversity.

关键词： Rice Resistance gene analogue Blast disease resistance

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 sciences, Lanzhou 730046, china College of animal science and technology, Shihezi university, Shihezi 832003, china 1 Key Laboratory of animal Virology of Ministry of Agriculture Lanzhou Veterinary Research Institute Chinese Academy of Agricultural Sciences College of animal science and technology Shihezi University

In this study, we constructed recombinant plasmid pcDNA3.1/P12X3C3D including P1, 2A, 3C, 3D and part of 2B gene of FMDV and pcDNA3.1/IFN containing the gene encoding bovine IFN-α. We inoculated the DNA vaccine pcDNA3.1/P12X3C3D 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/P12X3C3D 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/ P12X3C3D 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

INFLUENCE OF SURFACE HARDENING ON CONTACT FATIGUE LIFE OF NODULAR CAST IRON

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Acta Metallurgica Sinica(English Letters) 1990年第3期3卷 188-193页

作者： TAO Zengyi LUO Jiaming Huazhong university of science and technology,Wuhan,china TAO Zengyi,faculty of Metallic Materials,Dept.of Mechanical Engineering No.2,Huazhong university of science and technology,Wuhan 430074,china

The influence of laser surface melting and induction hardening on the surface structure,con- tact fatigue life and failure behaviour of the nodular cast iron has been *** con- tact fatigue life can be improved by both laser treatment and induction hardening,but the fail- ure process and type are different from each *** former is due to lumpy and deep spal- ling caused by crack propagation between the quenching zone and the substrate,and the latter is due to nubby and surface flaking caused by the oil wedged action into surface cracks.

关键词： surface hardening contact fatigue life laser melting induction hardening