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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 0.05), and only one gene had higher expression level in clones (p < 0.05). Furthermore, FGFR, GHR, HGFR and IGF1 genes showed lowered levels of both histone H4 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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Optimal controlled teleportation via several kinds of three-qubit states

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science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1529-1556页

作者： GAO Ting1,2, YAN FengLi2,3 & LI YouCheng3 1 college of Mathematics and Information science, hebei Normal university, Shijiazhuang 050016, china 2 Max-Planck-Institut für Quantenoptik, Hans-Kopfermann-Str. 1, D-85748 Garching, Germany 3 college of Physics and Information Engineering, hebei Normal university, Shijiazhuang 050016, china college of Mathematics and Information science Hebei Normal University Shijiazhuang 050016 China Max-Planck-Institut für Quantenoptik Hans-Kopfermann-Str. 1 D-85748 Garching Germany college of Physics and Information Engineering Hebei Normal University Shijiazhuang 050016 China

The probability of successful controlled teleportation of an unknown qubit using a general three-particle state is investigated. The analytic expressions of maximal probabilities via several kinds of tripartite states... 详细信息

关键词： controlled teleportation three-qubit state maximal probability

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Interactive group decision making procedure based on uncertain multiplicative linguistic preference relations

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Journal of Systems Engineering and Electronics 2010年第3期21卷 408-415页

作者： Zeshui Xu1,2,1.college of Economics and Management,Southeast university,Nanjing 210096,P.R.china 2.Institute of sciences,university of science and Technology of the PLA,Nanjing 210007,P.R.china college of Economics and Management Southeast UniversityNanjing 210096P.R.China Institute of sciences University of Science and Technology of the PLANanjing 210007P.R.China

Group decision making problems are investigated with uncertain multiplicative linguistic preference *** unbalanced multiplicative linguistic label set is introduced,which can be used by the experts to express their linguistic preference information over *** uncertain linguistic weighted geometric mean operator is utilized to aggregate all the individual uncertain multiplicative linguistic preference relations into a collective one,and then a simple approach is developed to determine the experts＇ weights by utilizing the consensus degrees among the individual uncertain multiplicative linguistic preference relations and the collective uncertain multiplicative linguistic preference ***,a practical interactive procedure for group decision making is proposed based on uncertain multiplicative linguistic preference relations,in which a possibility degree formula and a complementary matrix are used to rank the given ***,the proposed procedure is applied to solve the group decision making problem of a manufacturing company searching the best global supplier for one of its most critical parts used in assembling process.

关键词： group decision making uncertain multiplicative linguistic preference relations unbalanced multiplicative linguistic label set consensus degree interaction.

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Resource Allocation of agricultural science and Technology R&D

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Asian agricultural Research 2011年第3期3卷 61-64,69页

作者： BAI Li,ZHANG Li-ming,LI Xian-song college of Economics and Trade,agricultural university of hebei,baoding 071001,china School of Economics and Trade Agricultural University of Hebei

The status quo of resource allocation of agricultural science and technology R&D(research and development)both at home and abroad,including the amount and function of agricultural science and technology research funds,human resources in the resources of agricultural science and technology R&D,the efficiency of resource allocation of agricultural science and technology R&D,the management system of agricultural scientific innovation and the operation status of scientific funds,is *** problems in the current resource allocation of agricultural science and technology R&D are put forward,including unreasonable resource allocation;low efficiency,and low efficiency of the transformation of agricultural scientific *** highly effective resource allocation of agricultural science and technology R&D is analyzed from the aspects of resource allocation structure,environment,channel,spatial layout and industrial chain.

关键词： Resource of agricultural science and technology R&

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K_0-group and approximate similarity invariants of strongly irreducible operators

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science china Mathematics 2008年第12期51卷 2231-2252页

作者： HE Hua1, SHI Rui1,2 & MA XiuJuan1 1 School of science, hebei university of Technology, Tianjin 300130, china 2 School of Mathematics and Information science, hebei Normal university, Shijiazhuang 050016, china 1. School of science Hebei University of Technology Tianjin 300130 China 2. School of Mathematics and Information science Hebei Normal University Shijiazhuang 050016 China

Let H olenote a complex separable Hilbert space and L(H) denote the collection of bounded linear operators on H. An operator T ∈ L(H) is said to be strongly irreducible if T does not commute with any nontrivial idempotent. Herrero and Jiang showed that the norm-closure of the class of all strongly irreducible operators is the class of all operators with connected spectrum. This result can be considered as an "approximate inverse" of the Riesz decomposition theorem. In the paper, we give a more precise characterization of approximate invariants of strongly irreducible operators. The main result is: For any T ∈ L(H) with connected spectrum and ε > 0, there exists a strongly irreducible operator A, such that A - T < ε, V (A (A)) =～ N, K0(A (A)) ～= Z, and A (A)/rad A (A) is commutative, where A (A) denotes the commutant of A and rad A (A) denotes the Jacobson radical of A (A). The research is inspired by the recent similarity classification technique of Cowen-Douglas operators of Jiang Chunlan.

关键词： strongly irreducible operators Cowen-Douglas operators K0-group similarity orbit

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Sensitization and Intra-molecular Energy Transfer of Eu^(3+) by Tb^(3+) in Eu-Tb Binuclear Complexes/PMMA

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Journal of Wuhan university of Technology(Materials science) 2011年第3期26卷 398-402页

作者：韩晶 college of Mechatronic Engineering North University of China

A series of Eu0.5Tb0.5（TTA）3Phen/PMMA （TTA=thenoyltrifluoroacetone,Phen=phenanthroline） and Eu0.5Tb0.5（TTA）3Dipy/PMMA （Dipy=2,2’-dipyridyl） were prepared by in-situ *** structures of the composites were characterized by IR spectra and electron *** properties were investigated by UV-Vis spectra and fluorescence ***,the energy transfer models were set *** results indicated that polymer parts were attached with the rare-earth molecular parts in the composite luminescent ***0.5Tb0.5（TTA）3Phen/PMMA and Eu0.5Tb0.5（TTA）3Dipy/PMMA emitted mostly characteristic fluorescence of europium ion and intense red fluorescence with peak wavelength at 611.8 nm and bandwidth of 10.4 nm under UV excitation at 365 *** intensity of Eu0.5Tb0.5（TTA）3Phen/PMMA was found to be influenced with the content of *** fluorescence emission of europium ions was greatly sensitized by terbium ions and the enhancement of red emission was most likely due to the energy transfer enhancement from Tb3＋ to Eu3＋.

关键词： sensitization energy transfer rare-earth polymer in-situ polymerization

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Analysis of IGF2 mRNA expression and its methylation status between cattle yaks and their parents

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Progress in Natural science:Materials International 2009年第9期19卷 1063-1069页

作者： Zhenshan Liu a,b,1, Qifa Li a,1, Qingbo Zhang a, Xuguang Qu a, Liyan Dong a, Chamba Yang-zom c, Zhuang Xie a,*, Honglin Liu a a Laboratory of animal Reproductive Genetics and Molecular Evolution, college of animal science and Technology, Nanjing agricultural university, Nanjing 210095, china b Institute of animal Husbandry and Veterinary Medicine, Shandong Academy of agricultural sciences, Jinan 250100, china c college of Agriculture and animal Husbandry, Tibet university, Linzhi 860000, china [a]Laboratory of animal Reproductive Genetics and Molecular Evolution College of Animal Science and Technology Nanjing Agricultural University Nanjing 210095 China [b]Institute of Animal Husbandry and Veterinary Medicine Shandong Academy of Agricultural Sciences Jinan 250100 China [c]College of Agriculture and Animal Husbandry Tibet University Linzhi 860000 China

Cattle yaks are an F1 hybrid between cattle and yaks and exhibit significant hybrid vigor. However, cattle yaks are sterile males. To study the epigenetic aspects of this reproductive isolation, IGF2 mRNA expression in cattle yaks and their parents and the patterns of the IGF2 differentially methylated regions (DMR) were examined in blood and testes. The results showed that IGF2 expression in cattle yaks’ testes was lower than in their parents (P 2 DMR was highly methylated (above 90%) in blood and testes of cattle yaks, yaks and cattle, with the highest level in cattle yaks (P > 0.05). Our study showed that IGF2 plays an important role in bovine spermato-genesis and might be involved in cattle-yak male sterility. The methylation level of the IGF2 DMR was irrelevant to the lower expression of IGF2 in cattle yaks; other factors perhaps play roles in its expression.

关键词： Cattle yak Male sterility IGF2 gene mRNA expression DNA methylation

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Application of Improved PSO Algorithm in Hydraulic Pressing System Identification

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Journal of Iron and Steel Research International 2012年第9期19卷 29-35页

作者： YU Yu-zhen 1 , 2 , REN Xin-yi 2 , DU Feng-shan 2 , SHI Jun-jie 2 ( 1.Institute of Mechanical Engineering , hebei United university , Tangshan 063009 , hebei , china 2.Institute of Mechanical Engineering , Yanshan university , Qinhuangdao 066004 , hebei , china ) [a] Institute of Mechanical Engineering Hebei United University Tangshan 063009 Hebei China [b] Institute of Mechanical Engineering Yanshan University Qinhuangdao 066004 Hebei China

In view of characteristics of particle swarm optimization ( PSO ) algorithm of fast convergence but easily falling into local optimum value , a novel improved particle swarm optimization algorithm is put forward , and it is applicable to identify parameters of hydraulic pressure system model in strip rolling *** order to maintain population diversity and enhance global optimization capability , the algorithm is firstly improved by means of decreasing its inertia weight linearly from the maximum to the minimum and then combined with chaotic characteristics of ergodicity , randomness and sensitivity to initial *** the improved algorithm is used to identify parameters of hydraulic pressure system , the comparison of simulation curves and measured curves indicates that the identification results are reliable and close to actual situation.A new method was provided for hydraulic AGC system model identification.

关键词： hydraulic pressing system PSO algorithm chaos self-adaptive parameter identification

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Resolution method for overlapping peaks based on the fractional-order differential

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science china Chemistry 2007年第6期50卷 797-805页

作者： LI YuanLu1, YU ShengLin2 & ZHENG Gang2 1 college of Information & Control, Nanjing university of Information science & Technology, Nanjing 210044, china 2 college of Automation Engineering, Nanjing university of Aeronautics and Astronautics, Nanjing 210016, china 1. college of Information & Control Nanjing University of Information Science & Technology Nanjing 210044 China 2. college of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 China

Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals.

关键词： fractional-order differentiation filter, fractional-order differential, overlapping peaks, voltammetric peak

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Research on the Monitoring System of CNC Grinding Process Based on Acoustic Emission

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武汉理工大学学报 2006年第S1期28卷 310-313页

作者： HU Zhongxiang1,TENG Jiaxu1,YANG Junwei1,HUO Xiaojing2,SHI Xiaojun1 (1.National Key Laboratory for Remanufacturing,Beijing 100072,china 2.M&E Engineering college of hebei agricultural university,baoding 071001,china) National Key Laboratory for Remanufacturing Beijing 100072China M&EEngineering college of hebei agricultural university Baoding 071001China

Using on-line monitoring during the CNC grinding process,the hazard case such as the crushing of grinding wheel and various safety accidents could be avoided,and the optimum time for dressing and replacing grinding wheel could also be determined,and hence,the service life of the grinding wheel could be prolonged and grinding quality could be improved. To overcome the limitation of some traditional techniques in which some parameters including the grinding power and force,torque and so on were monitored,the acoustic emission (AE) technique,which provides high sensitivity and responding speed,were developed in the present paper. The mechanism of AE during grinding was reviewed. Moreover,a virtual AE monitoring system,which could monitor the grinding state under different working conditions during the grinding,has been developed based on the Virtual Instruments technique. Some experiments were also performed on the internal grinder. The results showed that the AE signals became stronger with increasing the main shaft speed and grinding depth or decreasing the distance between the AE sensor and grinding area.

关键词： on-line monitoring virtual instruments CNC grinding acoustic emission

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