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Aberrant histone H4 acetylation in dead somatic cell-cloned calves

Progress in Natural science:Materials International 2008年第7期18卷 813-818页

作者： Lei Zhang a,b,*, Shaohua Wang a, Qiang Li a, Xiangdong Ding c, Yunping Dai a, Ning Li a,* a State Key Laboratory for Agrobiotechnology, china agricultural university, Beijing {2., china b Beijing Gene & Protein Biotechnology Co. LTD, Beijing {2., china c college of animal science and technology, china agricultural university, Beijing {2., china State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China Beijing Gene & Protein Biotechnology Co. LTD Beijing 100094 China college of animal {2. and technology China Agricultural University Beijing 100094 China

In somatic cell-cloned animals, inefficient epigenetic reprogramming can result in an inappropriate gene expression and histone H4 acetylation is one of the key epigenetic modifications regulating gene expression. In this study, we investigated the levels of histone H4 acetylation of 11 development-related genes and expression levels of 19 genes in lungs of three normal control calves and nine aber- rant somatic cell-cloned calves. The results showed that nine studied genes had decreased acetylation levels in aberrant clones (p 0.05). Whereas 13 genes had significantly decreased expression (p 0.05), and only one gene had higher expression level in clones (p 4 acetylation and expression in aberrant clones than in controls, and the level of histone H4 acetylation was even more lowered in aberrant clones than those in controls. It was suggested that the lower levels of histone H4 acetylation in aberrant clones caused by the previous memory of cell differentiation might not support enough chromatin reprogramming, thus affecting appropriate gene expressions, and growth and development of the cloned calves. To our knowledge, this is the first study on how histone H4 acetylation affects gene expression in organs of somatic cell-cloned calves.

关键词： Somatic cell-cloned calves Histone H4 acetylation Gene expression Lungs

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Genetic polymorphisms of milk epithelial mucin of yaks

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Progress in Natural science:Materials International 2006年第11期16卷 1222-1226页

作者： ZHENG Yucai~1, ZHAO Xingbo~2.*, JIN Suyu~1, PENG Xianwen~1 and BAI Wenlin~1 (1. college of Life science and {2., Southwest university for Nationalities, Chengdu 610041, china 2. State Key Laboratory for Agrobio{2. and Ministry of Agriculture Key Laboratory of animal Genetics, Breeding and Reproduction, china agricultural university, Beijing 100094, china) [a]college of Life science and {2. Southwest University for Nationalities Chengdu China [b]State Key Laboratory for Agrobiotechnology and Ministry of Agriculture Key Laboratory of animal Genetics Breeding and Reproduction China Agricultural University Beijing China

Milk epithelial mucin (MUC1) of yaks was separated by SDS-polyacrylamide gel electrophoresis. A total of nine types of MUC1 were revealed in 42. yaks from five yak breeds including Maiwa yak, Jiulong yak, Tianzhu white yak, Qinghai yak and Tibetan yak. The molecular weights of MUC1 are from 163 kD to 2.8 kD, most of which are larger than those of bovine. Population genetic analysis shows that the gene frequency and genotype frequency of yak MUC1 differ among breeds, with relatively high gene heterozygosity. The five yak breeds studied fall into two groups according to their milk MUC1 gene frequency, suggesting that milk MUC1 exhibits specificities for local yak groups.

关键词： yak milk genetic polymorphism MUC1.

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Optimization of thermomechanical processes in Cu-Cr-Zr lead frame alloy using neural networks and genetic algorithms

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science china(Technological sciences) 2005年第5期48卷 510-520页

作者： SU Juanhua1,2. LIU Ping2. DONG Qiming2.& LI Hejun1 1. college of Materials science and Engineering, Northwestern Polytechnical {2., Xi’an 710072. china 2. college of Materials science and Engineering, Henan {2. of science and technology, Luoyang 471003, china 1. college of Materials science and Engineering Northwestern Polytechnical University 710072 Xi’an China 2. college of Materials science and Engineering Henan University of Science and Technology 471003 Luoyang China

The thermomechanical treatment process is effective in enhancing the properties of the lead frame copper alloy. In this study, an optimal pattern of the thermomechanical processes for Cu-Cr-Zr was investegated using an intelligent control technique consisting of neural networks and genetic algorithms. The input parameters of the artificial neural network (ANN) are the reduction ratio of cold rolling, aging temperature and aging time. The outputs of the ANN model are the two most important properties of hardness and conductivity. Based on the successfully trained ANN model, genetic algorithms (GA) are used to optimize the input parameters of the model and select perfect combinations of thermomechanical processing parameters and properties. The good generalization performance and optimized results of the integrated model are achieved.

关键词： Cu-Cr-Zr alloy, thermomechanical processing optimization, artificial neural network, genetic algorithms.

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Effect of physiological heterogeneity of E. coli population on antibiotic susceptivity test

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science china(Life sciences) 2007年第6期50卷 808-813页

作者： LIU YuQing1,3, ZHANG HuaiQiang2. SHEN JianZhong3 & GAO PeiJi2.1 Institute of animal science and Veterinary Medicine, Shandong Academy of {2. science, Jinan 2.0100, china 2.State Key Laboratory of Microbial technology, Shandong university, Jinan 2.0100, china 3 college of Veterinary Medicine, china agricultural university, Beijing 100094, china 1. Institute of animal science and Veterinary Medicine Shandong Academy of Agricultural Science Jinan 250100 China 3. college of Veterinary Medicine China Agricultural University Beijing 100094 China 2. State Key Laboratory of Microbial technology Shandong University Jinan 250100 China

According to the instantaneous growth rate (dN/dt) of E. coli CVCC2.9 growing in batch culture, the entire growth progress was distinguished into four phases: accelerating growth phase, constant growth phase, decelerating growth phase; declining phase, in each of which obvious variation in physiological; biochemical properties was detected, including total DNA, total protein,; MTT-dehydrogenase activity, etc., that led to difference in their antibiotic susceptivity. Antibiotic susceptivity of the population sampled from each phase was tested by Concentration-killing Curve (CKC) approach following the formula N=N 0/{1+exp[r·(x-BC 50)]}, showing as normal distribution at the individual cell level for an internal population, in which the median bactericidal concentration BC 50 represents the mean level of susceptivity, while the bactericidal span BC 199=(2.nN 0)/r indicates the variation degree of the antibiotic susceptivity. Furthermore, tested by CKC approach, the antibiotic susceptivity of E. coli CVCC2.9 population in each physiological phase to gentamicin or enoxacin was various: susceptivity of the population in the constant growth phase; declining phase all increased compared with that in the accelerating growth phase for gentamicin but declined for enoxacin. The primary investigations revealed that the physiological phase should be taken into account in the context of antibiotic susceptivity; research into antimicrobial mechanism. However there are few reports concerned with this study. Further research using different kinds of antibiotics with synchronized continuous culture of different bacterial strains is required.

关键词： instantaneous growth rate, batch culture, physiological heterogeneity, concentration-killing curve, antibiotic susceptivity test

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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 {2., Tai’an 2.1018, china 2.college of Materials science and Engineering, {2. of science and technology, Beijing 100083, china 3 college of Material science and Engineering, Beijing {2. of Chemical technology, Beijing 10002., 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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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,{2., Beijing 100083, china 2.college of Engineering, Ocean university of china, Qingdao 2.6071, 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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Mixed boundary conditions for piezoelectric plates

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science china(Physics,Mechanics & Astronomy) 2009年第5期52卷 755-761页

作者： GAO Yang 1 ,XU SiPeng 2.&ZHAO BaoSheng 3 1college of science,{2. agricultural university,Beijing 100083,{2. 2.0} of Engineering,Ocean university of china,Qingdao 2.6071,{2. 3 School of Mechanical Engineering,university of science and {12. of Liaoning,Anshan 114044,{2. college of science China Agricultural University Beijing 100083 China college of Engineering Ocean University of China Qingdao 266071 China School of Mechanical Engineering University of Science and Technology of Liaoning Anshan 114044 China

For plate bending and stretching problems in piezoelectric materials,the reciprocal theorem and the general solution of piezoelasticity are applied in a novel way to obtain the appropriate mixed boundary conditions accurate to all order.A decay analysis technique is used to establish necessary conditions that the prescribed data on the edge of the plate must satisfy in order that it should generate a decaying state within the *** the case of axisymmetric bending and stretching of a circular plate,these decaying state conditions are obtained explicitly for the first time when the mixed conditions are imposed on the plate *** are then used for the correct formulation of boundary conditions for the interior solution.

关键词： boundary conditions piezoelectric plates mixed data bending problems stretching problems

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Expression of the Tribolium castaneum (Coleoptera: Tenebrionidae) hsp83 gene and its relation to oogenesis during ovarian maturation

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Journal of Genetics and Genomics 2010年第8期37卷 513-522页

作者： Jingjing Xu 1, Juan Shu 1, Qin Zhang Key Laboratory of animal Genetics and Breeding of the Ministry of Agriculture, college of animal science and technology, china agricultural university, Beijing 100193, china [a] Key Laboratory of animal Genetics and Breeding of the Ministry of Agriculture College of Animal Science and Technology China Agricultural University Beijing 100193 China

Heat shock proteins （HSP） can protect organisms and cells from thermal damage. In this study, we cloned the full length cDNA encoding the HSP83 protein （the homologue of HSP90） of Tribolium castaneum（red flour beetle）. The isolated cDNA contains the full coding sequence, a partial 5＇ untranslated region of 55 bp and the complete 3＇ untranslated region. We found the hsp83 gene is located on chromosome 5 of the T. castaneum genome. The predicted HSP83 protein sequence has a high similarity （on average 86.77%） with that of other insect species. The expression of the hsp83 gene in the whole body and in the ovary could be induced with heat stress （40℃ for 1 h） in newly hatched （within 3 h post emergence） and mature （10 days post emergence） beetles. Under normal conditions, the hsp83 expression in the ovary is about 3-fold higher than in the whole body at both stages. No significant difference in hsp83 expression was observed between the two ovarian developmental stages regardless if the beetles were treated with heat shock or not. The expression of the HSP83 protein in the whole body could also be induced with heat stress in newly hatched and mature beetles. However, in the ovary, HSP83 was only expressed in the follicle cells of mature beetles and not in newly hatched beetles, regardless if the beetles were treated with heat shock or not. Furthermore, the females were not able to produce mature oocytes after knock-down of the hsp83 expression by injecting dsRNA. These results suggest that the HSP83 protein is involved in protection against heat stress and could be involved in oogenesis during ovarian maturation of T. castaneum.

关键词： hsp83 cDNA cloning Tribolium castaneum expression heat shock

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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 {2. of science and technology, Wuhan 430074, china 2. Institute of Laser technology and Engineering, Huazhong {2. of science and technology, Wuhan 430074, china 3. Mechanical Engineering college, Hubei {2. of technology, Wuhan 430068, china 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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Pattern phenomena in an rf discharge dusty plasma system

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science china(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2. YE Maofu2.& WANG Long2.1. college of science,{2., Beijing 100083, china 2. Institute of Physics, Chinese Academy of sciences, Beijing 100080, china 1. college of science China Agricultural University Beijing 100083 China 2. Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

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