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

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 {2. 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 2.6} of {2. {3. {2. and Key Laboratory of Nuclear Analysis Techniques, chinese academy of Sciences, P.O. Box 918, {12. 10003., China 3.uhan institute of {2. and Mathematics, State Key Laboratory of Magnetic Resonance and Atomic and Molecular {2., 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 {2. {3. 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

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De-interlacing technique based on total variation with spatial-temporal smoothness constraint

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Science in China(Series F) 2007年第4期50卷 561-575页

作者： YIN XueMin1,2.3, YUAN JianHua1,2. LU XiaoPeng1,2.& zou MouYan1,2.1 {2. of Electronics, {3. {2. of Sciences, beijing 100080, China 2.Graduate School, {3. {2. of Sciences, beijing 10003., China 3.Jiuquan Satellite Launch Center, Lanzhou 73.750, China institute of Electronics Chinese Academy of Sciences Beijing China Graduate School Chinese Academy of Sciences Beijing China Jiuquan Satellite Launch Center Lanzhou China

This paper introduces a new method of converting interlaced video to a progressively scanned video and image, The new method is derived from Bayesian framework with the spatial-temporal smoothness constraint and the MAP is done by minimizing the energy functional, The half-quadratic regularization method is used to solve the corresponding partial differential equations （PDEs）, This approach gives the improved results over the conventional de-interlacing methods, Two criteria are proposed in the paper, and they can be used to evaluate the performance of the de-interlacing algorithms,

关键词： video processing de-interlacing total variation spatio-temporai smoothness constraint PDEs half-quadratic regularization

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Exploration of combined adjustment laws about IGV,stator and rotational speed in off-design conditions in an axial compressor

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中国科学：技术科学英文版 2010年第4期53卷 969-975页

作者： HU YanMing1,2.& NIE ChaoQun1 1 Key Laboratory of Advanced energy and Power Technology,institute of Engineeting Thermo{2.,{3. academy of Science,beijing 100190,China 2.Graduate School of {3. academy of Sciences,beijing 100190,China Key Laboratory of Advanced energy and Power Technology Institute of Engineeting Thermophysics Chinese Academy of Science Beijing China Graduate School of chinese academy of Sciences Beijing China

Experimental investigations are performed in a three-stage low-speed axial compressor with variable inlet guide vanes(IGV) and adjustable *** characteristics of the compressor,especially the efficiency and stall margin,are analyzed in design and off-design operation conditions by adjusting stagger angles of IGV and stators as well as changing the rotational *** experimental results show that the off-design performance of the multistage axial compressor is improved by restaggering of IGV and stators related to rotational *** the background of engineering applications,digital signal processing(DSP) technique is used to realize online adjustment of stagger angles according to the corresponding relations between incidence angles of rotor and rotational speed.

关键词： axial compressor IGV surge DSP techniques off-design

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Ordovician-Silurian Boundary Extinction and Its Relationship to Iridium and carbon Isotope Anomalies

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Acta Geologica Sinica(English Edition) 1990年第1期64卷 81-92页

作者： Wang Xiaofeng Chai Zhifang Yichang institute of Geology and Minieral Resources, chinese {2. of Geological Sciences, Yichang. Hubei institute of high energy, Academia Sinica, beijing Liu Linqun Yichang institute of Geology and Mineral Resources Chinese Academy of Geological Sciences Yichang Hubei China

The abundance distributions of more than 40 elements in the No. 502.Ordovician-Silurian (O/S) bounda-ry section at Fenxiang, Yichang have been studied by RNAA and INAA. The results show that in the bounda-ry bed, there is a distinctive Ir anomaly because the Ir concentration abruptly increases to 0.64 ppb.Furthermore, the Ir is positively correlated in abundance variation with some siderophile and sulphophile ele-ments. In the same bed of the O/S boundary section at Huanghuachang, Yichang, there is also a δ^(13.C excur-sion. These geochemical signs support the hypothesis that the terminal Ordovician mass extinction was proba-bly related to extraterrestrial event, and provide new evidence for defining the O/S boundary between theHirnantia-Kinnella and G. persculptus Zones.

关键词： Ordovician-Silurian Boundary Extinction and Its Relationship to Iridium and carbon Isotope Anomalies Chen Wang

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Experimental investigation on a parabolic trough solar collector for thermal power generation

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Science China(Technological Sciences) 2010年第1期53卷 52-56页

作者： LIU QiBin1,WANG YaLong1,2.GAO ZhiChao1,2.SUI Jun1,JIN HongGuang1 & LI HePing3.1 institute of Engineering Thermo{2.,{2. {3. of Sciences,beijing 100190,China 2.Graduate University of {2. {3. of Sciences,beijing 100049,China 3.China Huadian Engineering Co.,Ltd,beijing 100044,China institute of Engineering Thermophysics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of Sciences Beijing China China Huadian Engineering Co. Ltd Beijing China

Developing solar thermal power technology in an effective manner is a great challenge in *** this paper an experiment platform of a parabolic trough solar collector system(PTCS) was developed for thermal power generation,and the performance of the PTCS was experimentally investigated with synthetic oil as the circulate heat transfer fluid(HTF).The solar collector's efficiency with the variation of the solar flux and the flow rate of the HTF was *** collector efficiency of the PTCS can be in the range of 40%-60%.It was also found that there existed a specified delay for the temperature of the HTF to response to the solar flux,which played a significant role in designing the *** heat loss effect on collector efficiency was also studied,which was about 2.0 W/m for the receiver with a 180°C temperature difference between the collector temperature and the ambient temperature,amounting to about 10% of the total solar energy incident on the *** encouraging results can provide fundamental data for developing the parabolic trough solar thermal power plant in China.

关键词： solar energy parabolic trough solar collector collector efficiency lag behind heat loss

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REE Geochemistry of VMS and SEDEX Ores in China

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Acta Geologica Sinica(English Edition) 1997年第3期71卷 263-272页

作者： Song Xuexin Xu Qingsheng Guo Yuemin Mao Xueying and Ouyang Hong institute of Mineral Deposits, chinese {2. of Geological Sciences, {3. institute of high energy physics, chinese {2. of Sinices, {3. institute of Mineral Deposits Chinese Academy of Geological Sciences Beijing institute of high {2. {3. Chinese Academy of Sinices Beijing [?]Song Xuexin Born in 193. and graduated from the Department of Geology and Geography Peking University in 1963 and from the Graduate School Chinese Academy of Geological Sciences in 1966. He has been doing research work mainly on economic geology ore genesis and geochemistry in the Institute of Mineral Deposits Chinese Academy of Geological Sciences and now is Research Professor at the Institute of Mineral Deposits Chinese Academy of Geological Sciences. He was a Research Fellow of Alexander von Humboldt-Foundation FRG from 1983 to 1985 and in 1991 1993 and 1995.

REE ratios and patterns for massive pyrite ore and massive cuprous pyrite ore ofthe Baiyinchang orefield are quite similar to those for quartz keratophyritic tuff and quartzalbitophyre of the same orefield. However, massive cuprous pyrite ore of the Ashele Cu-Zn de-posit is similar to basalt-diabase of the same district in REE geochemistry. Comparison of thechinese VMS ores with those from Rio Tinto, Spain and Que River, Australia, in REEgeochemistry has been made. REE ratios and patterns of bedded-massive and massive ores ofthe Changba-Lijiagou Zn-Pb deposit, the second largest SEDEX deposit in China are similarto those of their host rocks, the Qinling shales of Devonian age and the Changba *** three types of ore and their host rocks of the Dongshengmiao pyrite (pyrrhotite)-Zn-Pbdeposit have parallel REE ratios and patterns.

关键词： VMS ore SEDEX ore REE geochemistry REE pattern REE parameter

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Electronic structure and magnetism of Fe-doped SiC nanotubes

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Science China(physics,Mechanics & Astronomy) 2010年第9期53卷 1582-1589页

作者： ZHANG WeiHu1,2.3,ZHANG FuChun3.ZHANG ZhiYong4,LU ShuYuan5 & YANG YanNing3.1 Xi’an institute of Optics and Precision Mechanics,chinese {3. of Sciences,Xi’an 710068,China 2.Graduate University of chinese {3. of Sciences,beijing 100049,China 3.College of physics and Electronic Information,Yan’an University,Yan’an 716000,China 4 Information Science and Technology Institution,Northwest University,Xi’an 71012.,China 5 Department of Telecommunications,Xi’an institute of Posts and Telecommunications,Xi’an 71012.,China Xi’an institute of Optics and Precision Mechanics Chinese Academy of Sciences Xi’an China Graduate University of chinese academy of Sciences Beijing China College of physics and Electronic Information Yan’an University Yan’an China Information Science and Technology Institution Northwest University Xi’an China Department of Telecommunications Xi’an Institute of Posts and Telecommunications Xi’an China

The electronic structure and magnetic properties of Fe-doped SiC nanotubes are investigated by using the first-principles method based on density functional theory(DFT) in the local spin density approximation(LSDA).The calculation results indicate that the SiC nanotube of Fe substitution for C exhibits antiferromagnetism while ferromagnetism features prominently when Fe substitutes *** is a kind of half-metal magnetic *** formation energy calculation results show that the formation energy of ferromagnetic structure is {2.2.eV lower than that of antiferromagnetic *** atoms are more likely to replace Si ***-orbit coupling induces electron spin polarization in the ground ***,the doping Fe atoms make relaxation towards the outside of the tube to some extent and larger geometric distortion occurs when Fe substitutes C,but the whole geometric structure of SiC nanotubes is not damaged due to the *** is revealed in the calculation of energy band structure and density of states that more dispersed distribution of energy levels is produced near the Fermi *** Fe substitution for Si,obviously there are spin-split and intense p-d hybrid effects by Si {2. electron spins and Fe {2. electron spins localized at the exchanging interactions between magnetic transitional metal(TM) *** electronic density results indicate that system magnetic moments are mainly generated by the unpaired {2. electrons of Fe *** these results show that the transition metal doping SiC nanotube could be a potential route to fabricating the promising magnetic materials.

关键词： SiC nanotube the first-principles doped magnetic properties

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Optimization and comparison of accelerating cavities for the SSRF

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Nuclear Science and Techniques 1997年第3期 51-54页

作者： Chen Ming 1, Guo Yi Gang 1, Qin Jiu 2. Wang Guang Wei 3. ( 1 Shanghai institute of Nuclear Research, the {2. {2. of Sciences, Shanghai 2.1800 2. institute of high energy physics, the {2. {2. of Sciences, beijing 10003.

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关键词： RF cavity high order modes(HOM) SSRF Feasibility studies

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Nearly degenerate ground states of a checkerboard antiferromagnet and their bosonic interpretation

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Science China(physics,Mechanics & Astronomy) 2024年第1期67卷 84-89页

作者： Haiyuan zou Fan Yang Wei Ku Key Laboratory of Polar Materials and Devices(MOE) School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China Department of physics Beijing Institute of TechnologyBeijing 100081China Tsung-Dao Lee institute Shanghai 200240China Key Laboratory of Artificial Structures and Quantum Control(Ministry of Education) Shanghai 200240China Shanghai Branch Hefei National LaboratoryShanghai 201315China

The spin-1/2.model system with antiferromagnetic(AF) couplings on a J1-J2.heckerboard lattice, known as the planar pyrochlore model, is strongly frustrated and associated with a two-to-one dimensional crossover. Using the Projected Entangled Simplex States tensor network ansatz, we identify a large number of nearly degenerate states in the frustrated region(J_(1)2.).Specifically, we find the long-sought crossed-dimer valence bond solid(VBS) state to be the ground state at J_(1)≤J_(2., while various 1D AF correlated states take over the rest. We verify the stability of the VBS state against nematic perturbation. The corresponding bosonic picture provides an intuitive understanding of the low-energy physics. Particularly, it predicts weaker VBS states in the easy-plane limit, which we confirm numerically. Our results clarify the most essential ground state properties of this interesting system and demonstrate the usefulness of bosonic picture in dealing with frustrated magnetism.

关键词： tensor networks frustrated magnetism dimensional crossover degenerate states

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Some characteristics of the atmosphere during an adiabatic process

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Progress in Natural Science:Materials International 2006年第6期16卷 644-648页

作者： GAO Li, LI Jianping and REN Hongli (LASG, institute of Atmospheric physics, {2. {3. of Sciences, beijing 10002., China Graduate School of {2. {3. of Sciences, beijing 100049, China National Climate Center, Laboratory of Climate Studies, China Meteorological Administration, beijing 100081, China) LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate School of chinese academy of Sciences Beijing 100049 China National Climate Center Laboratory of Climatic Studies China Meterological Administration Beijing 100081 China

Some important characteristics of the atmosphere during an adiabatic process are investigated, which include the invariability of atmospheric entropy range and local surface potential temperature, the conservation of the atmospheric mass intervened between any isentropic surface and the ground, and the isentropic surface intersecting with the ground. The analysis shows that the atmospheric reference state (ARS) for investigation on available potential energy (APE) should be defined objectively as the state which could be approached from the existing atmosphere by adiabatic adjustment, and be related to initial atmospheric state before adjustment. For the initial atmosphere state at any time, its corresponding ARS is different from the one at another time. Based on the above-mentioned conclusions, the reference state proposed by Lorenz cannot be obtained physically, so a new conception, the conditional minimum total potential energy, is put forward in order to objectively investigate atmospheric APE.

关键词： available potential energy adiabatic isentropic surface atmospheric reference state conditional minimum total potential energy.

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