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Seasonal influence on the development of parthenotes and cloned embryos in pigs

Progress in Natural science:Materials International 2007年第10期17卷 1172-1176页

作者： Zhang Kun1, Zhang Yunhai3,4, Pan Dengke5. Ma Yufang1, Wei Hengxi1, Zhang Jian6, Li Xuyang7, Wang Shaohua1, Li yan2, Dai Yunping1,2 and Li Ning1(1. State Key Laboratory for Agrobiotechnology, College of Biological science, China agricultural university, Beijing 100094, China 2. JiPulin Biotech Ltd., Beijing 100094, China 3. Danish Institute of agricultural sciences, 8830 Tjele, Denmark 4. College of Animal science and Technology, Anhui agricultural university, Hefei 230036, China 5. Institute of Animal sciences, Chinese Academy of agricultural sciences, Beijing 100094, China 6. Animal Clinical Hospital, China agricultural university, Beijing 100094, China 7. Hebei Minghui Group of Pigs Breeding, Sanhe 065.00, China) State Key Laboratory for Agrobiotechnology College of Biological Science China Agricultural University Beijing 100094 China JiPulin Biotech Ltd. Beijing 100094 China Danish Institute of agricultural sciences 8830 Tjele Denmark College of Animal science and Technology Anhui Agricultural University Hefei 230036 China Institute of Animal sciences Chinese Academy of Agricultural Sciences Beijing 100094 China Animal Clinical Hospital China Agricultural University Beijing 100094 China 7. Hebei Minghui Group of Pigs Breeding Sanhe 065200 China

Seasonal influence on the developmental ability of porcine embryos was studied by comparisons of the number of cumulus-oocytes-complexes (COCs) per ovary pair and meiotic maturation ability of oocytes in different seasons; and by the observations on developmental competence of the parthenogenetic oocytes and cloned embryos collected from different seasons. We found that the number of COCs per ovary pairs was significantly higher in spring compared to the other seasons (P5.. However, no significant difference was found in the rate of oocytes progressing to MⅡ in four seasons (P5.. In addition, the rate of blastocyst formation of parthenogenetic embryos in summer was obviously declined compared to the other seasons (P5., and an increased blastocyst rate of cloned porcine embryos was found in spring compared to autumn and winter (P5.. The results suggest that there should be a seasonal influence on the developmental competence of porcine embryos.

关键词： pig cloned parthenogenetic season

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Isolation and Analysis of α-Gliadin Gene Coding Sequences from Triticum durum

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Journal of Integrative Agriculture 2007年第1期6卷 25-32页

作者： WANG Han-yan1, WEI Yu-ming1, 2, ZE Hong-yan1, 2 and ZHENG You-liang1, 21 Triticeae Research Institute, sichuan agricultural university, ya’an 625.14, P.R.China2 Key Laboratory of Crop Genetic Resources and Improvement in Southwest China, Ministry of Education/sichuan agricultural university,ya’an 625.14, P.R.China [a]Triticeae Research Institute Sichuan Agricultural University Ya'an 625014 P.R. China[b]Key Laboratory of Crop Genetic Resources and Improvement in Southwest China Ministry of Education/Sichuan Agricultural University Ya'an 625014 P.R. China

Three coding sequences of gliadins genes, designed as Gli2_Du1, Gli2_Du2 and Gli2_Du3, were isolated from thegenomic DNA of Triticum durum accessions CItr5.83. Gli2_Du1 and Gli2_Du2 contain 945.and 864 bp, encoding themature proteins with 314 and 287 amino acid residues, respectively. Gli2_Du3 is recognized as a pseudogene due to thestop codon occurring in the coding region. The pseudogenes, commonly occurring in gliadins family, are attributed to thesingle base change C → T. The amino acid sequences deduced from these gene sequences were characterized with thetypical structure of α-gliadin proteins, including the toxic sequences (PSQQQP). The peptide fraction PF(Y)PP(Q) isthought to be an extra unit of repetitive domain, slightly diverging from the previous report. Six cysteine residues wereobserved within two unique domains. Phylogenetic analysis showed Gli2_Du2 and Gli2_Du3 were closely related to thegenes on chromosome 6A, whereas Gli2_Du1 seems to be more homologous with the genes on chromosome 6B.

关键词： durum wheat α-gliadin gene clone sequence analysis

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Responses of ground-dwelling spiders to four hedgerow species on sloped agricultural fields in Southwest China

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Progress in Natural science:Materials International 2009年第3期19卷 337-346页

作者： Yuhong Wu a, Qingnian Cai b, Chaowen Lin c, Yibing Chenc, Yuying Lid, Xu Cheng b,* a College of Resources and Environmental sciences, China agricultural university, Beijing 100193, China b College of Agriculture and Biotechnology, China agricultural university, Beijing 100193, China c Institute of Soils and Fertilizers, {5. Academy of agricultural sciences, Chengdu 610066, China d College of life science and Technology, Nanyang Normal university, Nanyang 473061, China [a]College of Resources and Environmental sciences China Agricultural University Beijing 100193 China [b]College of Agriculture and Biotechnology China Agricultural University Beijing 100193 China [c]Institute of Soils and Fertilizers Sichuan Academy of Agricultural Sciences Chengdu 610066 China [d]College of Life Science and Technology Nanyang Normal University Nanyang 473061 China

Spiders are important predators in agroecosystems and contribute to the control of agricultural pest populations. Habitat manage- ment such as the creation of new semi-natural habitats around or within fields enhances spider abundance and species diversity. Using pitfall traps, we investigated the effects of four hedgerow plant species, which serve as undisturbed and permanent semi-natural habitats, on ground-dwelling spider activity density (a parameter of population density and relative activity) and species richness. Samples were collected over two winter wheat and two summer maize growing seasons during 2005.2007 in trial field 1 (slope gradient of 20%) and field 2 (slope gradient of 12%) at the Ziyang Experimental Site in sichuan Province, China. The hedgerow species evaluated were Amorpha fruticosa (field 1), Vetiveria zizanioides (field 1), Eulaliopsis binata (field 2), and Medicago sativa (field 2). Compared to control plots, hedgerow plots had significantly higher activity density and species richness of ground-dwelling spiders within strips in both fields 1 and 2 during the wheat growing season. The presence of hedgerow strips did not augment the activity density and species richness of ground-dwelling spiders within the crop fields during the wheat or maize growing seasons. The ground-dwelling spider activity density within hedgerow strips was significantly higher in the Vetiveria than in the Amorpha plots and in the Medicago than in the Eulaliopsis plots, and the species richness was significantly higher in the Vetiveria than in the Amorpha plots during the wheat season. Our results suggest that hedgerows may serve as important overwintering sites for ground-dwelling spiders during the wheat growing season. In addition, the diversification of agroecosystems by using hedgerow strips may be a viable strategy for maintaining ground-dwelling spider populations in agricultural areas. However, ground-dwelling spiders did not move into adjacent crop fields; the

关键词： Activity density Araneae Ground-dwelling Hedgerow Pitfall trapping Species richness

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Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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science China(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2, LIU GuoQuan2, LI ZhiLin3, FENG ChengMing1 1 Mechanical and Electronic Engineering College, Shandong agricultural university, Tai’an 271018, China 2 College of Materials science and Engineering, university of science and Technology, Beijing 100083, China 3 College of Material science and Engineering, Beijing university of Chemical Technology, Beijing 100029, China Mechanical Electronic Engineering College Shandong Agricultural University Tai’an 271018 China College of Materials science Engineering University of Science Technology Beijing 100083 China College of Material science Engineering Beijing University of Chemical Technology Beijing 100029 China

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements

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The refined theory of deep rectangular beams based on general solutions of elasticity

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science China(Physics,Mechanics & Astronomy) 2006年第3期49卷 291-303页

作者： GAO yang1 & WANG Minzhong2 1. College of science, China agricultural university, Beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engi- neering science, Peking university, Beijing 100871, China College of science China Agricultural University Beijing 100083 China State Key Laboratory for Turbulence Complex Systems Department of Mechanics Engineering science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional the- ory for a homogeneous isotropic beam is investigated. Based on elasticity theory, the re- fined theory of rectangular beams is derived by using Papkovich-Neuber solution and Lur’e method without ad hoc assumptions. It is shown that the displacements and stresses of the beam can be represented by the angle of rotation and the deflection of the neutral surface. Based on the refined beam theory, the exact equations for the beam without transverse surface loadings are derived and consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beam under transverse loadings are derived directly from the refined beam theory and are almost the same as the governing equations of Timoshenko beam theory. In two ex- amples, it is shown that the new theory provides better results than Levinson’s beam the- ory when compared with those obtained from the linear theory of elasticity.

关键词： deep rectangular beams,the refined theory,Papkovich-Neuber solution,Lur'e method,governing equation

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Lie comodules and the constructions of Lie bialgebras

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science China Mathematics 2008年第6期51卷 1017-1026页

作者： ZHANG LiangYun College of science,Nanjing agricultural university,Nanjing 210095.China College of science Nanjing Agricultural University Nanjing 210095 China

In this paper,we first give a direct sum decomposition of Lie comodules,and then accord- ing to the Lie comodule theory,construct some(triangular)Lie bialgebras through Lie coalgebras.

关键词： Lie coalgebras Lie comodules Lie bialgebras triangular Lie bialgebras 16W30

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Boundary conditions for the bending of a piezoelectric beam

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science China(Physics,Mechanics & Astronomy) 2008年第7期51卷 847-856页

作者： GAO yang1, XU SiPeng2 & ZHAO BaoSheng3 1 College of science, China agricultural university, Beijing 100083, China 2 College of Engineering, Ocean university of China, Qingdao 266071, China 3 School of Mechanical Engineering, university of science and Technology Liaoning, Anshan 114044, China 1. College of science China Agricultural University Beijing 100083 China 2. College of Engineering Ocean University of China Qingdao 266071 China 3. School of Mechanical Engineering University of Science and Technology Liaoning Anshan 114044 China

For beam bending in transversely isotropic piezoelectric media, the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate stress and mixed boundary conditions accurate to all orders for the beam of general edge geometry and loadings. By generalizing the method developed by Gregory and Wan, a set of necessary conditions on the edge-data for the existence of a rapidly decaying solution is established. The prescribed edge-data of the beam must satisfy these conditions in order that they could generate a decaying state within the beam. When stress and mixed conditions are imposed on the beam edge, these decaying state conditions for the case of bending deformation of piezoelectric beam are derived explicitly. They are then used for the correct formulation of boundary conditions for the beam theory solution (or the interior solution). Besides, an analytical solution of elastic beam is formulated to verify validity of our boundary conditions. For the stress data, our boundary conditions coincide with those obtained in conventional forms of beam theories. More importantly, the appropriate boundary conditions with two sets of mixed edge-data are obtained for the first time.

关键词： boundary conditions beam bending piezoelectric media decaying states regular states

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Investigation of changes in properties of water under the action of a magnetic field

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science China(Physics,Mechanics & Astronomy) 2008年第11期51卷 1621-1632页

作者： PANG XiaoFeng1,2 & DENG Bo1 1 Institute of life science and Technology, university of Electronic science and Technology of China, Chengdu 61005., China 2 International Centre for Materials Physics, Chinese Academy of sciences, Shenyang 110015. China 1. Institute of life science and Technology University of Electronic Science and Technology of China Chengdu 610054 China 2. International Centre for Materials Physics Chinese Academy of Sciences Shenyang 110015 China

The properties of water and their changes under the action of a magnetic field were gathered by the spectrum techniques of infrared, Raman, visible, ultraviolet and X-ray lights, which may give an insight into molecular and atomic structures of water. It was found that some properties of water were changed, and a lot of new and strange phenomena were discovered after magnetization. Magnetized water really has magnetism, which has been verified by a peak shift of X-ray diffraction of magnetized water + Fe3O4 hybrid relative to that of pure water + Fe3O4 hybrid, that is a saturation and memory effect. The properties of infrared and ultraviolet absorptions, Raman scattering and X-ray diffraction of magnetized water were greatly changed relative to those of pure water; their strengths of peaks were all increased, the frequencies of some peaks did also shift, and some new peaks, for example, at 5.98, 805. and 9340 cm?1, occurred at 25.C after water was magnetized. In the meanwhile, the magnetized effects of water are related to the magnetized time, the intensity of an externally applied magnetic field, and the temperature of water, but they are not a linear relationship. The study also showed a lot of new and unusual properties of magnetized water, for example, the six peaks in 3000–3800 cm?1 in infrared absorption, the exponential increase of ultraviolet absorption of wave with the decreasing wavelength of light of 200–300 nm, the frequency-shifts of peaks, a strange irreversible effect in the increasing and decreasing processes, as well as a stronger peak of absorption occurring at 5.°C, 70°C and 80°C, the existence of many models of motion from 85.C to 95.C in 8000–10000 cm?1, and so on. These results show that the molecular structure of water is very complicated, which needs further study. Furthermore, the macroscopic feature of mechanics, for instance, surface tension force of magnetized water, was also measured. Experiments discovered that the size in contact angle

关键词： pure water magnetized water magnetic-field physical property spectrum saturation and memory effect mechanical feature surface tension force polarization angles of contact

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The refined theory of transversely isotropic piezoelectric rectangular beams

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science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 473-486页

作者： GAO yang1 & WANG Minzhong2 1. College of science, China agricultural university, Beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engi- neering science, Peking university, Beijing 100871, China 1. College of science China Agricultural University Beijing 100083 China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engineering science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional theory for a transversely isotropic piezoelectric rectangular beam is investigated. Based on the piezoelasticity theory, the refined theory of piezoelectric beams is derived by using the general solution of transversely isotropic piezoelasticity and Lur'e method without ad hoc assumptions. Based on the refined theory of piezoelectric beams, the exact equations for the beams without transverse surface loadings are derived, which consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beams under transverse loadings are derived directly from the refined beam theory. As a special case, the governing differential equations for transversely isotropic elastic beams are obtained from the corresponding equations of piezoelectric beams. To illustrate the application of the beam theory developed, a uniformly loaded and simply supported piezoelectric beam is examined.

关键词： rectangular beams, the refined theory, piezoelectric, transversely isotropic.

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Study of immunological activity of coarse polysaccharide of Agaricus blazei murrill

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西南师范大学学报(自然科学版) 1999年第5期24卷 594-600页

作者： Tang Wei 1,Wang Qijun 2 1 College of physical Education,Southwest China Normal university,Chongqing 400715.2 Southwest agricultural university,Chongqing 400716 西南师范大学体育学院重庆西南农业大学重庆

The coarse polysaccharide extracted from the mycelium of Agaricus blazei Murrill was served as our experimental materials. The results exhibited that it can significantly increase spleen index and phagocytic rate of macrophage and strengthen non specific immunological level of organism. It can obviously raise rosette formation percentage of active T lymphocytes(Ea%) to promote the cellular immunological level of organism. Besides, it can noticeably increase the content of haemolysin that is a circulating antibody to enhance the immunological level of body fluid. Therefore, coarse polysaccharide of A. blazei Murrill has wide applications in health care and medicine and it is a good immune strengthening agent.

关键词： Agaricus blazei Murrill polysaccharide immunological activity \

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