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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 China College of Animal Science and technology China Agricultural University Beijing 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%, pnuclear maturation of oocytes increased significantly when IVM duration time was extended from 36 to 42.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 (2.% O2. in cleavage rate (70.6% vs. 67.1%, p2.3%, pnuclear maturation is greatly improved by prolonging IVM duration from 36 to 42.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.

气动磁镜实验装置ALIANCE-T ICRH天线的初步设计

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核聚变与等离子体物理 2024年

作者：张克卿曾秋孙郁杰 1.中国科学院合肥物质科学研究院 2.中国科学技术大学

介绍了气动磁镜实验装置(ALIANCE-T)的离子回旋共振加热(ICRH)系统天线的初步设计方案。目的是进一步提高等离子体参数和约束；采用了有限元分析软件COMSOL计算磁场分布，并据此确定ICRH慢波加热天线的共振频率和发射位置；通过HFSS天... 详细信息

介绍了气动磁镜实验装置(ALIANCE-T)的离子回旋共振加热(ICRH)系统天线的初步设计方案。目的是进一步提高等离子体参数和约束；采用了有限元分析软件COMSOL计算磁场分布，并据此确定ICRH慢波加热天线的共振频率和发射位置；通过HFSS天线仿真得到天线本身的阻抗，并结合数值计算得到等离子体的阻抗，从而设计相应的匹配电路。ICRH天线初步设计将为ALIANCE-T辅助加热提供合理的方案建议。

关键词：离子回旋共振加热气动磁镜天线仿真等效阻抗计算

Improved nuclear mass formula with an additional term from the Fermi gas model

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nuclear Science and Techniques 2024年第5期35卷 131-138页

作者： xiao-Yu Xu Li Deng Ai-xi Chen Hang Yang Amir Jalili Han-Kui Wang School of Science Zhejiang Sci-Tech UniversityHangzhou 310018China

nuclear mass is a fundamental property of nuclear physics and a necessary input in nuclear *** to the complexity of atomic nuclei and nonperturbative strong interactions,conventional physical models cannot completely describe nuclear binding *** this study,the mass formula was improved by considering an additional term from the Fermi gas *** nuclear masses in the Atomic Mass Evaluation Database were reproduced with a root-mean-square deviation(RMSD)of -1.86 MeV(1.92.MeV).The new mass formula exhibits good performance in the neutron-rich nuclear *** RMSD decreases to 0.393 MeV when the ratio of the neutron number to the proton number is≥1.6.

关键词： nuclear mass formula Neutron-rich nuclei Fermi-gas model

Design and construction of charged-particle telescope array for study of exotic nuclear clustering structure

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nuclear Science and Techniques 2024年第8期35卷 114-123页

作者： Zheng‑Li Liao xi‑Guang Cao Yu‑Xuan Yang Chang‑Bo Fu xian‑Gai Deng Shanghai Institute of Applied Physics Chinese Academy of SciencesShanghai 201800China University of Chinese Academy of Sciences Beijing 100049China Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China Zhengzhou University Zhengzhou 450001China Key Laboratory of nuclear Physics and Ion‑beam Application(MOE) Institute of Modern PhysicsFudan UniversityShanghai 200433China Shanghai Research Center for Theoretical nuclear Physics NSFC and Fudan University Shanghai 200438China

The exploration of exotic shapes and properties of atomic nuclei,e.g.,αcluster and toroidal shape,is a fascinating field in nuclear *** study the decay of these nuclei,a novel detector aimed at detecting multipleα-particle events was designed and *** detector comprises two layers of double-sided silicon strip detectors(DSSD)and a cesium iodide scintillator array coupled with silicon photomultipliers array as light sensors,which has the advantages of their small size,fast response,and large dynamic *** coupled with cesium iodide crystal arrays are used to distinguish multipleα*** detector array has a compact and integrated design that can be adapted to different experimental *** detector array was simulated using Geant4,and the excitation energy spectra of someα-clustering nuclei were reconstructed to demonstrate the *** simulation results show that the detector array has excellent angular and energy resolutions,enabling effective reconstruction of the nuclear excited state by multipleαparticle *** detector offers a new and powerful tool for nuclear physics experiments and has the potential to discover interesting physical phenomena related to exotic nuclear structures and their decay mechanisms.

关键词： Cluster decay Toroidal structure Telescope array SiPM Energy resolution

Molecular structure and biological function of proliferating cell nuclear antigen

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Progress in Natural Science:Materials International 2007年第10期17卷 1127-1135页

作者： Song Nanmeng1, Sang Jianli1 and Xu Heng2.1. Institute of Cell Biology, College of Life Science, Beijing Normal University, Beijing 100875, china 2. Emory University School of Medicine, GA 30332. USA) Institute of Cell Biology College of Life Science Beijing Normal University Beijing 100875 China Emory University School of Medicine GA 30332 USA

Proliferating cell nuclear antigen (PCNA) is the core component of replication complex in eukaryote. As a processive factor of DNA polymerase delta, PCNA coordinates the replication process by interacting with various replication proteins. PCNA appears to play an essential role in many cell events, such as DNA damage repair, cell cycle regulation, and apoptosis, through the coordination or organization of different partners. PCNA is an essential factor in cell proliferation, and has clinical significance in tumor research. In this article we review the functional structure of PCNA, which acts as a function switch in different cell events.

关键词： PCNA Function Switch PCNA Binding Motif Cell Cycle DNA Replication DNA Repair.

A 12.bit multichannel ADC for pixel detectors in particle physics and nuclear imaging

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Science china(Technological Sciences) 2010年第5期53卷 1208-1214页

作者： WEI Wei1,2.3,WANG Zheng1,3 & ZHAO JingWei1,3 1 Institute of High Energy Physics,Chinese Academy of Sciences,Beijing 100049,china 2.Graduate University of Chinese Academy of Sciences,Beijing 100049,china 3 Key Lab of {2. Detection technology and {2. Electronics of Chinese Academy of Sciences,Beijing 100049,china Institute of High Energy Physics Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Key Lab of nuclear Detection technology and nuclear Electronics of Chinese Academy of Sciences

Modern pixel detectors in nuclear and particle physics experiments and also in nuclear imaging,starve for highly integrated application specified integrated circuit(ASIC),whereas in{2. the study of ASIC still stays far away from practical *** lack of ASIC strictly limits the research and development of domestic high energy physics field.A 12.bit multichannel ADC designed for high density readout is introduced as a major candidate for solution.A precise model is discussed and the simulation fully agrees with the model,which indicates a key principle of *** is performed according to the given rule,and novel layout techniques are carried *** results in all aspects are also obtained,showing an excellent real performance,which satisfies the practical requirement.

关键词： application specified integrated circuit high density readout Wilkinson ADC multi-channel ADC

Parameter estimation for whole-body kinetic model of FDG metabolism

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Progress in Natural Science:Materials International 2006年第11期16卷 1164-1170页

作者： CUI Yunfeng~1, BAI Jing~1**, CHEN Yingmao~2.and TIAN Jiahe~2.1. Department of Biomedical Engineering, Tsinghua University, Beijing 100084, china 2. Department of nuclear Medicine, General Hospital of PLA, Beijing 100853, china) Department of Biomedical Engineering Tsinghua University Beijing 100084 China

Based on the radioactive tracer [ ~ 18 F]2.fluoro-2.deoxy-D-glucose （FDG）, positron emission tomography （PET）, and compartment model, the tracer kinetic study has become an important method to investigate the glucose metabolic kinetics in human body. In this work, the kinetic parameters of three-compartment and four-parameter model for the FDG metabolism in the tissues of myocardium, lung, liver, stomach, spleen, pancreas, and marrow were estimated through some dynamic FDG-PET experiments. Together with published brain and skeletal muscle parameters, a relatively complete whole-body model was presented. In the liver model, the dual blood supply from the hepatic artery and the portal vein to the liver was considered for parameter estimation, and the more accurate results were obtained using the dual-input rather than the single arterial-input. The established whole-body model provides the functional information of FDG metabolism in human body. It can be used to further investigate the glucose metabolism, and also be used for the simulation and visualization of FDG metabolic process in human body.

关键词： compartment model FDG PET parameter estimation.

A phenomenological equation of state for isospin asymmetric nuclear matter

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1494-1505页

作者： CHEN LieWen1,2.1 Department of Physics,Shanghai Jiao Tong University,Shanghai 2.02.0,china 2.Center of Theoretical nuclear Physics,National Laboratory of Heavy Ion Accelerator,Lanzhou 730000,china Department of Physics Shanghai Jiao Tong University Shanghai China Center of Theoretical nuclear Physics National Laboratory of Heavy Ion Accelerator Lanzhou China

A phenomenological momentum-independent(MID) model is constructed to describe the equation of state(EOS) for isospin asymmetric nuclear matter,especially the density dependence of the nuclear symmetry energy Esym(ρ).This model can reasonably describe the general properties of the EOS for symmetric nuclear matter and the symmetry energy predicted by both the sophisticated isospin and momentum dependent MDI model and the Skyrme-Hartree-Fock *** find that there exists a nicely linear correlation between Ksym and L as well as between J0/K0 and K0,where L and Ksym represent,respectively,the slope and curvature parameters of the symmetry energy at the normal nuclear density ρ0,while K0 and J0 are,respectively,the incompressibility and the third-order derivative parameter of symmetric nuclear matter at ρ*** correlations together with the empirical constraints on K0,L and Esym(ρ0) lead to an estimation of -477 MeV Ksat,2.-2.1 MeV for the second-order isospin asymmetry expansion coefficient for the incompressibility of asymmetric nuclear matter at the saturation point.

关键词： equation of state of nuclear matter isospin the symmetry energy

Progress of Lyman-alpha-based beam emission spectroscopy(Ly BES)diagnostic on the HL-2. tokamak

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Plasma Science and technology 2024年第3期26卷 118-125页

作者：周艺轩余羿许敏柯锐聂林徐皓赵光义刘灏袁子豪肖晨雨李继全肖池阶 the HL-2. Team Southwestern Institute of Physics Chengdu 610041People's Republic of China Sino-French Institute of nuclear Engineering and technology Sun Yat-sen UniversityZhuhai 519082People's Republic of China State Key Laboratory of nuclear Physics and technology School of PhysicsPeking UniversityBeijing 100871People's Republic of China

An edge Lyman-alpha-based beam emission spectroscopy(LyBES)diagnostic,using a heating NBI(neutral beam injection)system,is currently under development on the HL-2. *** 2.-channel edge LyBES,which is intended to measure the density fluctuation in plasma edge(from R=1960 mm to R=2.2. mm)with an improved spatial resolution of 3.3 mm,is a complement to the existing conventional beam emission spectroscopy(BES)*** this article,we introduce the progress of LyBES diagnostic,including the collection optics,the monochromator,and the detector *** reflectance of the collection mirrors is measured to be~82.at 12. nm,and the aberration geometrical radius of the collection optics is tested to be~150μm in the aimed *** linear dispersion of the LyBES monochromator is designed to be~0.09 nm mm^(-1).The bandwidth of the detector system with the 5×10^(7)V A^(-1)preamplifier gain is measured to be~2.0 kHz,and the peak-to-peak noise of the detector system is tested to be~16 *** finalized design,components development and testing of the LyBES diagnostic have been completed at present,and an overall performance of the LyBES diagnostic is to be confirmed in the next HL-2. campaign.

关键词： density fluctuation Ly BES BES vacuum ultraviolet