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Cu(Ⅱ) Potentiation of Alzheimer Aβ1-40 Cytotoxicity and Transition on its Secondary Structure

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Acta Biochimica et Biophysica Sinica 2006年第11期38卷 765-772页

作者： Xue-Ling DAI~1 Ya-Xuan SUN~2.Zhao-Feng JIANG~2. 1 college of Life science,Capital Normal {2.,beijing 100037,China 2.college of Applied sciences and Humanities,beijing union university,beijing 100083,China college of Life science Capital Normal UniversityBeijing 100037 China college of Applied sciences and Humanities Beijing Union UniversityBeijing 100083 China

Mounting evidence has shown that dyshomeostasis of the redox-active biometals such as Cuand Fe can lead to oxidative stress,which plays a key role in the neuropathology of Alzheimer's disease（AD）.Here we demonstrate that with the formation of Cu（Ⅱ）·Aβ1-40 complexes,copper markedly potentiatesthe neurotoxicity exhibited by β-amyloid peptide （Aβ）.A greater amount of hydrogen peroxide was releasedwhen Cu（Ⅱ）·Aβ1-40 complexes was added to the xanthine oxidase/xanthine system detected by potassiumiodide *** bound to Aβ1-40 was observed by electron paramagnetic resonance（EPR） *** dichroism （CD） studies indicated that copper chelation could cause a structuraltransition of Aβ.The addition of copper to Aβ introduced an increase on β-sheet as well as α-helix,whichmay be responsible for the aggregation of Aβ.We hypothesized that Aβ aggregation induced by copper maybe responsible for local injury in *** interaction between Cu2.and Aβ also provides a possible mechanismfor the enrichment of metal ions in amyloid plaques in the AD brain.

关键词： Alzheimer’s disease Cu(Ⅱ)·Aβ1-40 complex neuron injury Aβ secondary structure

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 2.1018, 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 10002., 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

Pattern phenomena in an rf discharge dusty plasma system

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science China(Physics,Mechanics & Astronomy) 2006年第5期49卷 588-596页

作者： HUANG Feng1,2. YE Maofu2.& WANG Long2.1. college of science, China Agricultural {2., beijing 100083, China 2. Institute of Physics, Chinese Academy of sciences, beijing 100080, China 1. college of science China Agricultural University Beijing 100083 China 2. Institute of Physics Chinese Academy of Sciences Beijing 100080 China

Various dust patterns are observed in an rf discharge dusty plasma system. According to the dust growth process from small to large in size, the formation of different dust patterns can be divided into two stages: the small-particle stage (or dust cloud stage), and the large-particle stage (or dust crystal stage). The evolution relations between different dust patterns with gas pressure changing are investigated. Dust voids, dust acoustic waves and strong turbulence modes are presented at the small-particle stage. The self-organized dust lattices and dust clusters are investigated at the large-particle stage. The static structure of a dust lattice is characterized by means of the pair correlation function. Dust clusters formed by particles with different numbers and the regular evolution of the clusters with gas pressure are also investigated. The packing sequences of dust clusters are verified through two-dimensional confined molecular dynamics simulations.

关键词： dusty plasma dust patterns

Synchronization of Digital Chaos in Secure Communication Systems

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Journal of university of science and Technology {2. 2001年第4期8卷 299-305页

作者： Geng Zhao, Deling Zheng, ShaojunHuang 1)college of Electric science and Technology {2.. {2. 100070, China 2.Information Engineering School, university of science and Technology {2.. beijing 100083, China Coll Elect Sci & Technol beijing Beijing 100070 Peoples R China Univ Sci & Technol beijing Informat Engn Sch Beijing 100083 Peoples R China

The theories of synchronization based on secure communications using digital chaos are presented. A new synchronous method-cycles-interval Pulse drive is developed and realized. Experimental results show it is available, and in order to reduce synchronous noise, a method using model references solves the ratio of signal power to noise power, so the secure communication system can be realized.

关键词： digital chaotic synchronization cycles-interval pulses drive synchronous noise model reference

The refined theory of deep rectangular beams based on general solutions of elasticity

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science China(Physics,Mechanics & Astronomy) 2006年第3期49卷 291-303页

作者： GAO Yang1 & WANG Minzhong2.1. college of science, China Agricultural {2., beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engi- neering science, Peking {2., beijing 100871, China college of science China Agricultural University Beijing 100083 China State Key Laboratory for Turbulence Complex Systems Department of Mechanics Engineering science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional the- ory for a homogeneous isotropic beam is investigated. Based on elasticity theory, the re- fined theory of rectangular beams is derived by using Papkovich-Neuber solution and Lur’e method without ad hoc assumptions. It is shown that the displacements and stresses of the beam can be represented by the angle of rotation and the deflection of the neutral surface. Based on the refined beam theory, the exact equations for the beam without transverse surface loadings are derived and consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beam under transverse loadings are derived directly from the refined beam theory and are almost the same as the governing equations of Timoshenko beam theory. In two ex- amples, it is shown that the new theory provides better results than Levinson’s beam the- ory when compared with those obtained from the linear theory of elasticity.

关键词： deep rectangular beams,the refined theory,Papkovich-Neuber solution,Lur'e method,governing equation

CONTROLLED RELEASE FROM PDMAEMA GELS PREPARED BY GAMMA RADIATION

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Chinese Journal of Polymer science 2002年第5期20卷 409-412页

作者： Ning Liu Min Yi Shuang-ji Chen Hong-fei Ha college of Chemistry and Molecular Engineering Peking university {2. 100871, China Department of Biochemistry college of Applied arts and science, beijing union university beijing 100083. China Peking Univ Coll Chem & Mol Engn Beijing 100871 Peoples R China beijing union Univ Coll Appl Arts & Sci Dept Biochem Beijing 100083 Peoples R China

Poly(N,N-dimethylaminoethyl methacrylate) (polyDMAEMA) hydrogels prepared by gamma-irradiation showed obvious temperature-sensitivity in a temperature range of 38-40degreesC and pH-sensitivity at pH=2.5. They also showed electric response behavior although it was not typical. The hydrogels were used in controlled release at different pH, temperature, and electric voltage. The release rates of methylene blue (MB) from the gels at 52.egreesC and pH=1.2. were faster than those at 2.degreesC and pH=10.56, respectively. In addition, the release rate at a field voltage of 5.0 was also faster than that without electric field.

关键词： poly(N,N-dimethylaminoethyl methacrylate) environmental sensitivity hydrogel controlled release

The refined theory of transversely isotropic piezoelectric rectangular beams

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science China(Physics,Mechanics & Astronomy) 2006年第4期49卷 473-486页

作者： GAO Yang1 & WANG Minzhong2.1. college of science, China Agricultural {2., beijing 100083, China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engi- neering science, Peking {2., beijing 100871, China 1. college of science China Agricultural University Beijing 100083 China 2. State Key Laboratory for Turbulence and Complex Systems and Department of Mechanics and Engineering science Peking University Beijing 100871 China

The problem of deducing one-dimensional theory from two-dimensional theory for a transversely isotropic piezoelectric rectangular beam is investigated. Based on the piezoelasticity theory, the refined theory of piezoelectric beams is derived by using the general solution of transversely isotropic piezoelasticity and Lur'e method without ad hoc assumptions. Based on the refined theory of piezoelectric beams, the exact equations for the beams without transverse surface loadings are derived, which consist of two governing differential equations: the fourth-order equation and the transcendental equation. The approximate equations for the beams under transverse loadings are derived directly from the refined beam theory. As a special case, the governing differential equations for transversely isotropic elastic beams are obtained from the corresponding equations of piezoelectric beams. To illustrate the application of the beam theory developed, a uniformly loaded and simply supported piezoelectric beam is examined.

关键词： rectangular beams, the refined theory, piezoelectric, transversely isotropic.

Synthesis and thermodynamic analysis of nano-La2.3

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Progress in Natural science:Materials International 2007年第7期17卷 838-844页

作者： Liu Lili~(1,2. Tang Jie~2.Li Yuxiang~1 Zhang Mei~(1**) Wang Xidong~(1,3) (1.Department of Physical Chemistry,university of science and Technology {2.,beijing 100083,China 2.National Institute for Materials science,Segen 1-2.1,Tsukuba 305-0047,Japan 3.college of Engineering,{2. university,{2. 100871,China) [a]Department of Physical Chemistry University of Science and Technology Beijing Beijing China [b]National Institute Materials science Tsukuba Jpan [c]college of Engineering Beijing University Beijing China

The thermodynamic parameters of La（NO3）3and La（OH）3are evaluated and the thermodynamics of nano-La2.3syn- thetic process is *** the base of thermodynamic analysis,La2.3nano-powders are prepared by the sol-gel method and the experi- ment scheme is designed by an orthogonal *** dry-gelatin is analyzed with differential thermal analysis/thermo-gravimetric analy- sis（TGA-DTA）and X-ray diffraction *** microstructure of nano-La2.3powders is observed by transmission dectron micro- *** synthetic parameters affecting the average grain size and dispersivity of nano-La2.3particles are experimentally examined and *** the results indicate that nano-La2.3particles well-dispersed are obtained and the average grain size is in the range of 2.—50 nm.

关键词： nano-La2.3 sol-gel thermodynamic analysis

Development and application of ergodicity model with FRCM and FLAR for hydrological process

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science China(Technological sciences) 2009年第2期52卷 379-386页

作者： WANG HongRui1, FENG QiLei2. LIN Xin3 & ZENG WenYi4 1 college of Water science, Key Laboratory for Water and Sediment sciences of the Ministry of Education, beijing Normal university, beijing 100875, China 2.School of science, beijing Institute of Education, beijing 100011, China 3 School of Mathematical sciences, beijing Normal university, beijing 100875, China 4 college of Information science and Technology, beijing Normal university, beijing 100875, China 1. college of Water science Key Laboratory for Water and Sediment Sciences of the Ministry of Education Beijing Normal University Beijing 100875 China 2. School of science Beijing Institute of Education Beijing 100011 China 3. School of Mathematical sciences Beijing Normal University Beijing 100875 China 4. college of Information science and Technology Beijing Normal University Beijing 100875 China

In this paper, a new ergodic property analysis model of hydrological process is proposed based on fuzzy-rough c-means clustering (FRCM), autocorrelogram, and fuzzy least absolute regression (FLAR). A precipitation time series (1951―2.04) from Shanghai Hydrology Station is then analyzed with the model. The results show that the precipitation time series of April, May, June, and September has er-godic property. We conclude that in the long run, the precipitation of April, May, June, and September will not keep decreasing; it will converge to its mean value in some period.

关键词： hydrological process ergodic autocorrelogram fuzzy-rough c-means clustering fuzzy least absolute regression