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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 100094, china b beijing Gene & Protein Biotechnology co. ltd, beijing 100094, china c college of Animal Science and technology, china Agricultural University, beijing 100094, china State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China beijing Gene & Protein Biotechnology co. ltd Beijing 100094 China college of Animal Science 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 controls and clones (p > 0.05), and only one gene had higher expression level in clones (p 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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Calculating model of mass action concentrations for Ag-Au-Cu melts

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Rare Metals 2002年第1期21卷 43-47页

作者： ZHANG Jian Metallurgy School, University of Science and technology beijing, beijing 100083, china Metallurgy School University of Science and Technology Beijing 北京 100083

Based on phase diagrams and measured activities, the calculatingmodel of mass action concentrations for het- erogeneous meltsAg-Au-Cu was formulated. Calculated results agree with the improvedresults of recent research work, Showing that the model formulatedcan reflect the structural characteristics of these melts. In thismodel, without the help Of any empirical parameters, only threeequilibrium constants are used, hence it is simple, lear, andfavorable to the sim- Plification of calculation.

关键词： activity mass action concentration eutectic Solid solution

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Analysis and control on Fracture of 20Mn2A High Tensile Steel for Round Link Chain

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Journal of Iron and Steel Research International 2011年第S1期18卷 898-902页

作者： CAO Shu-wei 1,2,KANG Yong-lin 1,3,ZHAO Xian-ping 2,YANG Chang-chun 1 (1.School of Materials Science and Engineering,University of Science and technology beijing,beijing 100083,china 2.technology Center of Anyang Iron & Steel Group co.,ltd.,Anyang 455004,Henan,china 3.State Key Laboratory for Advanced Metals and Materials,University of Science and technology beijing,beijing 100083,china) Univ Sci & Technol beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China Anyang Iron & Steel Grp co ltd Ctr Technol Anyang 455004 Henan Peoples R China Univ Sci & Technol beijing State Key Lab Adv Met & Mat Beijing 100083 Peoples R China

Based on the phenomenon of brittle fracture occurred during tensile test for 20Mn2A high strength circular chain used in coal mines,the fracture property is regarded as intercrystalline brittle one after macroscope observation and metallographic *** is analysed that the intercrystalline brittle fracture is due to high tempering temperature and limited processing site where final products are piled together after heat treatment,which lead to a lower cooling rate of internal chain,with Si,Mn and P etc elements segregating and enriching in the austenite grain boundary and forming high tempering *** these circular chains are tempered again for one hour at 670℃,and oil-cooled rapidly,due to the reversibility of high temper brittleness for structural alloy steel,the high temper brittleness can be eliminated and products are completely qualified after tensile inspection.

关键词： high strength circular chain metallographic examination brittle fracture high tempering brittleness improvement measures

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Stabilization of Chaotic Time Series by Proportional Pulse in the System Variable Based on Genetic Algorithm

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 228-229页

作者： Qing Li Deling Zheng Jianlong Zhou(Information Engineering School, University of Science and technology beijing, beijing 100083, china)(Handan iron and Steel co., Handan 056015, china) Information Engineering School University of Science and Technology Beijing Beijing 100083 China Handan Iron and Steel co. Handan 056 015 China

The PPSV (Proportional Pulse in the System Variable) algorithm is a convenient method for the stabilization of the chaotic time series. It does not require any previous knowledge of the system. The PPSV method also has a shortcoming, that is, the determination off. is a procedure by trial and error, since it lacks of optimization. In order to overcome the blindness, GA (Genetic Algorithm), a search algorithm based on the mechanics of natural selection and natural genetics, is used to optimize the λi The new method is named as GAPPSV algorithm. The simulation results show that GAPPSV algorithm is very efficient because the control process is short and the steady-state error is small.

关键词： stabilization chaotic time series genetic algorithm

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Being the Pioneer of Life Sciences in china——Introduction to beijing Genomics Institute

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Genomics, Proteomics & Bioinformatics 2004年第1期2卷 59-63页

作者： Xin Zhang beijing Genomics Institute, beijing 101300, china. beijing Genomics Institute Beijing 101300 China

The beijing Genomics Institute (BGI) of Chinese Academy of Sciences (CAS) wasofficially founded in December 2003. Its predecessor, beijing Huada Genomics Research Center, haspresented significant contributions to the development of life sciences in china by its excellentscientific innovations and achievements in the last five years. From the participation ofInternational Human Genome Project (HGP) to the independent completion of the whole-genome draft andfine maps of Chinese super hybrid rice genome, from the porcine genome research cooperated withDenmark to the international chicken genome research, and from the silkworm genome projectaccomplished together with The Southwest Agriculture University of china to the great contributionsto the national campaign against SARS, all these facts illustrate that BGI not only has afirst-class scientific research power in the world but also is full of devotion to the flourish ofscience and nation. During these years, we have upheld the strategy of ''Advance through projects,strive for innovation, grow through cooperation'', in the aim of making BGI as one of the pioneers ofCAS climbing the peak of life sciences in the world.

关键词： Chinese Academy of Sciences beijing Genomics Institute innovation life sciences

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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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Fusion tracking in color and infrared images using joint sparse representation

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Science china(Information Sciences) 2012年第3期55卷 590-599页

作者： LIU HuaPing1,2,3 & SUN FuChun1,2,3 1Department of computer Science and technology, Tsinghua University, beijing 100084, china 2State Key Laboratory of Intelligent technology and Systems, beijing 100084, china 3Tsinghua National Laboratory for Information Science and technology, beijing 100084, china 1. Department of computer Science and technology Tsinghua University Beijing 100084 China2. State Key Laboratory of Intelligent Technology and Systems Beijing 100084 China3. Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China

Currently sparse signal reconstruction gains considerable interest and is applied in many fields. In this paper, a similarity induced by joint sparse representation is designed to construct the likelihood function of particle filter tracker so that the color visual spectrum and thermal spectrum images can be fused for object tracking. The proposed fusion scheme performs joint sparse representation calculation on both modalities and the resultant tracking results are fused using min operation on the sparse representation coefficients. In addition, a co-learning approach is proposed to update the reference templates of both modality and enhance the tracking robustness. The proposed fusion scheme outperforms state-of-the-art approaches, and its effectiveness is verified using OTCBVS database.

关键词： joint sparse representation fusion tracking color image infrared image

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EFFECT OF NITROGEN ON GRAPHITE MORPHOLOGY IN GRAY CAST IRON

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Acta Metallurgica Sinica(English Letters) 1993年第8期6卷 151-155页

作者： ZHAI Qijie HU Hanqi University of Science and technology beijing,beijing,china Faculty of Foundry,University of Science and technology beijing,beijing 100083,china beijing Univ of Science and Technology Beijing China

The distribution of N and morphology of graphite in gray cast iron containing N were studicd by adopting the man-made specimens of Fe-C-Si-Mn alloys with some N added. The N adsorbed along the interfaces between graphite and matrix together with solid- solutioned in graphite is believed to be the principal cause of morpholongical variation of graphite.

关键词： gray cast iron graphite morphology N

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The mathematical model of wetting angle of heterogeneous nucleation

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Science china(Technological Sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, SONG Bo1, MAO Jinghong2 & ZHAO Pei3 1. School of Metallurgical and Ecological Engineering, University of Science and technology beijing, beijing 100083, china 2. School of Material Science, University of Science and technology beijing, beijing 100083, china 3. Central Iron and Steel Research Institute, beijing 100081, china 1. School of Metallurgical and Ecological Engineering University of Science and Technology Beijing 100083 Beijing China 2. School of Material Science University of Science and Technology Beijing 100083 Beijing China 3. Central Iron and Steel Research Institute 100081 Beijing China

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 40, and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2O3 are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.

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Theorems for Testing Local Activity of CNN and Application to Cardiac Purkinje Equations

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 139-146页

作者： Lequan Min(Applied Science School, University of Science and technology beijing, beijing 100083, china) Applied Science School University of Science and Technology Beijing Beijing 100083 China

The theorems for testing the local in one-port cellular neural/inear network (CNN) cells with four local state variables are presented. Using the theorems computes the bifurcation diagrams of the cardiac Purkinje fiber (CPE) equations Which describethe long-lasting action and pace-maker potentials of the Purkinje fiber of the heart. The computer simulation shows that periodic trajectories or convergent trajectories of the CPF Equations can be foun if the cormsponing cell Parameters are located in a positive domainbut nearby edge of chaos. In particular a heart with approximate normal frequency of heartbeat but non-normal electrocardiogram maysuddenly stop by slightly perturbing the parameters of the corresponding CPF Equations when the Paramders are located nearby the edge of chaos in the bifurcation diagrams. This research seems to interpret reasonbly the phenomena that patients with cardiac diseases might suddenly die without warning.

关键词： cellular neural network local activity cardiac Purkinje fiber heartbeat

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