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Correlation of Behavior Changes and BOLD Signal in Alzheimer-like Rat Model

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 803-810页

作者： Zheng-Hui HU#, Xiao-Chuan WANG1#, Li-Yun LI3. Mai-Li LIU3. Rong LIU1, Zhiqun LING1, Qing TIAN1, Xiao-Wei TANG, Yi-Gen WU2., and Jian-Zhi WANG1* Department of Physics and Bio-X disciplinary Laboratory, Zhejiang University, Hangzhou 3.002.,china 1 Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, Wuhan 43.03., china 2.nstitute of High energy Physics and Key Laboratory of Nuclear Analysis Techniques, Chinese Academy of Sciences, P.O. Box 918, {3. 10003., china 3.uhan Institute of Physics and Mathematics, State Key Laboratory of Magnetic Resonance and {12. and Molecular Physics, Chinese Academy of Sciences, Wuhan 43.071, china Department of Physics and Bio-X disciplinary Laboratory Zhejiang UniversityHangzhou 310027China Department of Pathophysiology Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China Wuhan Institute of Physics and Mathematics State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Chinese Academy of SciencesWuhan 430071 China Institute of High energy Physics and Key Laboratory of Nuclear Analysis Techniques Chinese Academy of SciencesP.O. Box 918 Beijing 100039 China

To explore a potential means for the early diagnosis of Alzheimer disease, we studied the relationship of resting T2. signal and tau hyperphosphorylation/spatial memory deficit. The rat model with tau hyperphosphorylation and spatial memory deficit was established by bilateral hippocampi injection of isoproterenol (IP). Then, the correlative alteration between resting T2. signal and spatial memory retention was assessed with blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) study and Morris Water Maze test, and Western blot was employed to confirm tau hyperphosphorylation. The analysis showed following results. (1) Tau phosphorylation at Ser3.6/Ser404 and Ser199/Ser2.2.was signifi- cantly increased in IP-injected rats as detected by PHF-1 and tau-1, respectively. (2. An AD-like spatial memory retention disturbance was induced at 2. h after isoproterenol injection. (3. A sensitivity threshold of resting T2. signal intensity, which separated the IP-treated rats from vehicle control, was obtained by applying linear regression analysis, and an estimated sensitivity statistical threshold was at 3..62. These results suggest that resting T2. signal may serve as a noninvasive quantitative marker in predicting AD-like spatial memory deficits and tau hyperphosphorylation.

关键词： Alzheimer disease (AD) functional magnetic resonance imaging (fMRI) isoproterenol (IP) Morris Water Maze diagnosis

The anharmonic effect study of coupled Morse oscillators for the unimolecular reaction

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Science china Chemistry 2008年第12期51卷 1146-1152页

作者： YAO Li1,2.& LIN Sheng-Hsien2.3. Department of Physics, Dalian Maritime University, Dalian 11602., china 2.Institute of {2. and Molecular Sciences, Academia Sinica, Taipei 10764, china 3.Department of Applied Chemistry and Institute of Molecular Sciences, Chiao-Tung University, Hsinchu 3.051, Taiwan, china 1. Department of Physics Dalian Maritime University Dalian 116026 China 2. Institute of atomic and Molecular Sciences Academia Sinica Taipei 10764 China 3. Department of Applied Chemistry and Institute of Molecular Sciences Chiao-Tung University Hsinchu 30051 Taiwan China

The importance of anharmonic effect in dissociation of molecular systems especially clusters has been noted. In this paper, we shall study the effect of coupled anharmonic oscillator of the standard bilinear form (SBF) Morse oscillator (MO) potential on unimolecular reaction. We shall use the systematic theoretical approach, YL method, proposed by Yao and Lin (YAO L, et. al. J Phys Chem A, 2.07, 111(2.): 672.-672.), which can evaluate anharmonic effects on the rate constants based on the transition state theory. In treating the anharmonic effect with the Morse oscillator potential on unimolecular reactions under collision-free conditions by using the RRKM (Rice-Ramsperger-Kassel-Marcus) theory, the in-verse Laplace transformation of the partition functions was used to obtain the total amount of state and density of state by using the first-order and the second-order approximations of the saddle-point method. To demonstrate the anharmonic effect of the SBF Morse model, we choose some model systems and a real reaction as examples.

关键词： anharmonic effect standard bilinear form Morse oscillator rate constant RRKM theory

AFM study on the adsorption and aggregation behavior of dissolved humic substances on mica

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Science china Chemistry 2006年第3期49卷 256-266页

作者： GE Xiaopeng1, ZHOU Yanmei2. Lü Chunhua1 & TANG Hongxiao1 1. State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, beijing 100085, china 2. School of Civil Engineering & Architecture, beijing Jiaotong University, beijing 100044, china 1. State Key Laboratory of Environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China 2. School of Civil Engineering & Architecture Beijing Jiaotong University Beijing 100044 China

Humic substances constitute the major organic fractions of soils, sediments and natural waters, and play a dominant role in the binding, mobilization, transport and ultimate fate of organic contaminants in subsurface systems. In this paper, two humic acid samples, Guanting and Tianjin, with different origin and chemical compositions have been investigated with AFM imaging for their adsorption and aggregation behaviors on mica. While the Tianjin humic sample is found to form small spheres with 2.0 to 3.0 nm in diameter at lower concentrations, irregular loop-chain assemblies of hundreds of nanometer in diameter with the chain width of about 40 nm are dominant for the Guanting humic sample, which may attribute to the more polar aliphatic fractions in the chemical composition in the latter. The heterogeneous and polydisperse nature of humic substances with multiple structural features, such as sponge-like structures, perforated sheets, aggregate of spheres, branches and chain-like assemblies etc., is apparent at higher concentrations for both humic samples, showing morphologically new evidence for the dominant view of the humic dual-mode sorption model. With naphthalene introduced, the assemblies of Guanting humic substances clearly become more compact with significantly narrowed branches and less porous the perforated sheet-like structures. It is indica- tive of that smaller nanometer scale rings present along the perforated assemblies could potentially represent hydrophobic domains, which may facilitate the adsorption and aggregation of naphthalene onto the natural particle surfaces and therefore lead to an important role of dissolved humic sub- stances in the sorption of environmental pollutants.

关键词： atomic force microscopy (AFM) dissolved humic substances morphology aggregation adsorption

Theoretical study of ZnO adsorption and bonding on Al_2._3.0001) surface

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Science china(Physics,Mechanics & Astronomy) 2004年第6期47卷 664-675页

作者： LI Yanrong1,YANG Chun1,2.XUE Weidong1,LI Jinshan3.& LIU Yonghua3.1.Institute of Microelectronics and Solid State Electronics,University of Electronic Science and Technol- ogy of {2.,Chengdu 610054,{2. 2.Institute of Mathematics and Software Science,Sichuan Normal University,Chengdu 610068,{2. 3.Institute of Chemical Materials,{2. Academy of Engineering Physics,Mianyang 62.000,{2. Institute of Microelectronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China Institute of Mathematics and Software Science Sichuan Normal University Chengdu 610068 China Institute of Chemical Materials China Academy of Engineering Physics Mianyang 621000 China

ZnO adsorption on sapphire (0001) surface is theoretically calculated by using a plane wave ultrasoft pseudo-potential method based on ab initio molecular dynamics. The results reveal that the surface relaxation in the first layer Al-O is reduced, even eliminated after the surface adsorption of ZnO, and the chemical bonding energy is 43..3.±3..6) kJ·mol?1. The chemical bond of ZnO (0.185 ± 0.01 nm) has a 3.° angle away from the adjacent Al-O bond, and the stable chemical adsorption position of the Zn is deflected from the surface O-hexagonal symmetry with an angle of about 3.°. The analysis of the atomic populations, density of state and bonding electronic density before and after the adsorption indicates that the chemical bond formed by the O2.of the ZnO ? and the surface Al3. has a strong ionic bonding characteristic, while the chemical bond formed by the Zn2. and the surface O2.has an obvious covalent characteristic, which ? comes mainly from the hybridization of the Zn 4s and the O 2. and partially from that of the Zn 3. and the O 2..

关键词： α-Al2.3.(0001) ZnO ab initio molecular dynamics chemical adsorption density of states

Approximation analytical solutions for a unified plasma sheath model by double decomposition method

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Nuclear Science and Techniques 1998年第4期9卷 193-197页

作者： Fang Jin-Qing (china Institute of atomic {2. {3. 102.13.

A anified plasma sheath model and its potential equation are proposed. Any higher-ordor-approximation analytical solutions for the unified plasma sheath potential equa tiop are derived by double decomposition method.

关键词：等离子体屏蔽模型双分解方法近似分析

Brownian ratchets driven by flashing noise strength

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Chinese Science Bulletin 1999年第21期44卷 1956-1961页

作者： ZHAO Tongjun, ZHAN Yong, ZHUO Yizhong and WU XizhenDepartment of Applied Mathematics and Physics , Hebei University of Technology , Tianjin 3.013., {2. {2. Institute of atomic {3., beijing 102.13. {2. Institute of Theoretical Physics, Chinese Academy of Sciences , beijing 100080, {2. Corresponding author Dept. of Appl. Math. and Physics Hebei University of Technology Tianjin 300130 China china Institute of atomic {2. Beijing 102413 China Institute of Theoretical Physics Chinese Academy of Sciences Beijing 100080 China

The stochastic transport driven by flashing multi-noise sources in a ratchet is studied. The stationary current versus the noise strength and the colored noise correlated time T is obtained . At a fixed flip rate and strength of the colored noises, the novel phenomenon of the current reversal occurs as T reaches a certain value. More than one reversal point exists when

关键词： flashing force ratchet current reversal Langevian equation.

Track Fading and Its Applications in Archaeology, Tectonics and Geothermal Chronology in china

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Journal of Earth Science 2013年第4期24卷 645-651页

作者：郭士伦袁万明陈宝流黄慰文刘顺生 Department of Nuclear Physics China Institute of Atomic Energy School of Earth Sciences and Resourses China University of Geosciences Department of Radioisotopes China Institute of Atomic Energy Institute of Vertebrate Paleontology and Paleoanthropology Chinese Academy of Sciences Guangzhou Institute of Geochemistry Chinese Academy of Sciences

Track fading is a basic phenomenon in track science and has been the source of informa- tion in geosciences. This article summarizes the knowledge of track fading and gives some examples of successful applications of track fading in archaeology, tectonics and geothermal chronology in china. The applications of track fading are classified into 5 modes：（1） mode of complete fading （annealing）; （2. mode of partial fading; （3. use of the dependence of track fading on time and temperature; （4） use of the differences of track fading between coexisting minerals; and （5） use of fading-reduced track length. Track fading mechanisms hints that scientists in geothermal chronology should adopt microprobes for quantitative elemental analysis to determine the detailed chemical compositions of each mineral grain or at least of the grains from each position of geological structures in order that one becomes well aware of the relation between the track fading behavior and chemical compositions of the mineral used.

关键词： track fading archaeology tectonics geothermal chronology.

Electronic structure and magnetism of R（Fe,Si）12.（R=Y,Nd）

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Science china(Physics,Mechanics & Astronomy) 2006年第2期Mechanics & Astronomy) .卷 195-202页

作者： SUN Guang’ai1, CHEN Bo1, DU Honglin2. FAN Zhijian1, GAO Tao3.& QI Xinhua3.. Institute of Nuclear Physics and Chemistry, {2. Academy of Engineering Physics, Mianyang 62.900, {2. 2. Department of physics, Peking university, beijing 100871, {2. 3. Institute of atomic and Molecular Physics, Sichuan University, Chengdu 610065, {2.

The newly developed full-potential linearized augmented plane wave (LAPW) and local orbitals (lo) based on standard APW methods are briefly introduced, and the structure and magnetic properties of R(Fe, Si)12.compounds (R = Y, Nd) are calculated using the method. The distribution of Si at different sites is analyzed based on total energy of one crystal unit with structure having been optimized. The characters of magnetic mo-ments, total density of states (TDOS) and partial density of states (PDOS) for different crystal sites Si occupies are obtained and analyzed. The results show that the total mag-netic moments of RFe10Si2.(R = Y, Nd) are larger than those of RFe10M2.(M = Ti, V, Cr, Mn, Mo and W) and the hybridization mechanism is seen as follows. Si(8j) reduce the mag-netic moments of Fe at three sites, however, Si(8f) mainly reduce the magnetic moments of Fe(8i) and Fe(8j) atoms. The Curie temperature is markedly enhanced by the introduc-tion of Si atoms according to spin fluctuation of DOS at Fermi level.

关键词： (L)APW+lo method R(Fe Si)12.R = Y Nd) magnetic moment Density of state.

A first-principles investigation into the hydrogen bond interaction in β-HMX

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Science china(Physics,Mechanics & Astronomy) 2010年第6期53卷 1080-1085页

作者： CHEN Fang 1 ,ZHANG Hong 1,2.ZHAO Feng 3.,MENG ChuanMin 3.& CHENG XinLu 1 1 Institute of {2. and Molecular Physics,Sichuan University,Chengdu 610065,china 2.School of Physical Science and Technology,Sichuan University,Chengdu 610065,china 3.Laboratory for Shock Wave and Detonation Physics Research,Southwest Institute of Fluid Physics,china Academy of Engineering Physics,Mianyang 62.900,china 1. Institute of atomic and Molecular Physics Sichuan University Chengdu 610065 China2. School of Physical Science and Technology Sichuan University Chengdu 610065 China3. Laboratory for Shock Wave and Detonation Physics Research Southwest Institute of Fluid Physics China Academy of Engineering Physics Mianyang 621900 China

A theoretical study of structural and electronic properties of β-HMX crystal is performed using density-functional theory(DFT). The total density of states(TDOS) is presented. The atomic orbit projected density of state(PDOS) from the p-type orbit of C,N,O and the s-type orbit of H is discussed. The study by analyzing the PDOS shows that the structure of β-HMX crystal possesses C-H···O intra- and inter-molecular hydrogen-bonding. There exists a hydrogen bonding between H5 -1s and O12.-2. orbits,between H19 -1s and O2. -2. orbits of intra molecules,and between H19 -1s and O2. -2. orbits of inter molecules. The Mulliken population analysis is also made.

关键词： structural property hydrogen bond β-HMX population analysis