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Protective Effects of Vitamin E against Oxidative Damage Induced by Aβ(1-40)Cu(Ⅱ)Complexes

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Acta Biochimica et Biophysica Sinica 2007年第2期39卷 123-130页

作者： Xueling DAI~1 Yaxuan SUN~2 and Zhaofeng JIANG~2 ~1college of Life science,Capital Normal University,Bejing 100037,China ~2college of Applied sciences Humanities of Beijing Union University,Beijing 100083,China college of Life science Capital Normal UniversityBeijing 100037 China college of Applied sciences and Humanities of Beijing Union UniversityBeijing 100083 China

β-amyloid peptide （Aβ） is considered to be responsible for the formation of senile plaques,which is the hallmark of Alzheimer's disease （AD）.Oxidative stress,manifested by protein oxidation andlipid peroxidation,among other alterations,is a characteristic of AD brain.A growing body of evidence hasbeen presented in support of Aβ1-40forming an oligomeric complex that binds copper at a CuZn superoxidedismutase-like binding site. Aβ1-40Cu（Ⅱ） complexes generate neurotoxic hydrogen peroxide （H2O2） from O2via Cue+ reduction,though the precise reaction mechanism is *** toxicity of Aβ1-40or the Aβ1-40Cu（Ⅱ）complexes to cultured primary cortical neurons was partially attenuated when （+）-α-tocopherol （vitamin E）as free radical antioxidant was added at a concentration of 100 μ*** data derived from lactate dehydro-genase （LDH） release and the formation of H2O2confirmed the results from the MTT *** findingsindicate that copper binding to Aβ1-40can give rise to greater production of H2O2, which leads to a break-down in the integrity of the plasma membrane and subsequent neuronal *** treated with vitaminE exhibited much slighter damage,suggesting that vitamin E plays a key role in protecting neuronal cellsfrom dysfunction or death.

关键词： Aβ1-40Cu(II)complex vitamin E neuronal oxidative damage H2O2 generation lactate dehydrogenase(LDH)release

Preparation, characterization, viscosity and thermal conductivity of CaCO_3 aqueous nanofluids

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science China(Technological sciences) 2010年第2期53卷 360-368页

作者： ZHU HaiTao1, LI ChangJiang2, WU DaXiong1, ZHANG CanYing1 & YIN YanSheng2 1 college of Materials science and Engineering, Qingdao University of science and Technology, Qingdao 266042, China 2 Department of Materials, Ocean University of China, Qingdao 266003, China college of Materials science and Engineering Qingdao University of Science and Technology Qingdao China Department of Materials Ocean University of China Qingdao China

CaCO3 aqueous nanofluids were prepared by dispensing aqueous CaCO3 paste into distilled water under ultrasonic vibration. The actual microstructures of the CaCO3 nanofluids with different particle volume fractions were characterized by freeze etching replication transmission electron microscopy (FERTEM). Thermal conductivity and rheological behavior of the nanofluids were measured by standard analyzers. The results show that CaCO3 paste as raw material for nanofluids is advantageous to reducing aggregation of primary nanoparticles. The effective viscosities and effective thermal conductivities of the CaCO3 nanofluids are related to the aggregates of nanoparticles and can be well predicted by the modified Krieger & Dougherty formula and the modified Hamilton & Crosser model, respectively.

关键词： CaCO3 nanofluid thermal conductivity viscosity microstructure

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Relationship between surface subsidence factor and mining depth of strip pillar mining

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中国有色金属学会会刊：英文版 2011年第S3期21卷 594-598页

作者： GUO Wen-bing1, 2, HOU Quan-lin 1, ZOU You-feng2 1. college of Earth science, Graduate University of Chinese Academy of sciences, Beijing 100049, China 2. School of Energy science and Engineering, Henan Polytechnic University, Jiaozuo 454000, China college of Earth science Graduate University of Chinese Academy of Sciences Beijing 100049 China School of Energy science and Engineering Henan Polytechnic University Jiaozuo 454000 China

Strip pillar mining is one of the most important technical measures to control mining subsidence in China. Mining depth is one of the most important factors that can affect the mining subsidence in strip pillar mining. Six numerical simulation models were set up to simulate the surface subsidence of strip pillar mining in different mining depths. The mining depth in these six models ranges from 300 to 800 m. The simulated results were compared and analyzed. The formula was established based on the simulated results. It demonstrated that the subsidence of strip pillar mining method is related to mining depth. While the other conditions are the same, the subsidence of strip pillar mining increases with the increase of mining depth by logarithmic relationship.

关键词： subsidence factor strip pillar mining mining depth numerical simulation

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Investigation of thermoluminescence in Li_2B_4O_7 phosphors doped with Cu, Ag and Mg

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science China(Physics,Mechanics & Astronomy) 2007年第3期50卷 311-320页

作者： XIONG ZhengYe1,2, TANG Qiang2 & ZHANG ChunXiang2 1 college of science, Guangdong Ocean University, Zhanjiang 524088, China 2 School of Physics science and Engineering, Sun Yat-sen University, Guangzhou 510275, China college of science Guangdong Ocean University Zhanjiang China School of Physics science and Engineering Sun Yat-sen University Guangzhou China

Li2B4O7 （LBO）:Cu,Ag,Mg phosphors have been prepared by the sintering technique. The roles of the Ag and Mg dopants in the phosphors have been studied using the methods of thermoluminescence （TL） glow curves and TL 3D spectra. The results indicated that proper concentrations of Ag and Mg can enhance the TL of LBO:Cu. It was also indicated that the intensity of TL peak at 130℃ is reduced with the in- creasing Ag concentration, and enhanced with the increasing Mg concentration. From the TL 3D spectra, three emission bands （λ1 = 421 nm, λ2 = 380 nm, λ3 = 350 nm） were observed: the intensity of low energy emission band is reduced and that of the high energy is enhanced with the increasing dopant Ag; on the contrary, the intensity of low energy emission band is enhanced and that of the high energy one is reduced with the increasing dopant Mg.

关键词： thermoluminescence spectra borate lithium

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Internal relative humidity and creep of concrete with modified admixtures

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Progress in Natural science:Materials International 2011年第5期21卷 426-432页

作者： Zhi-hai HE~(1,2),Chun-xiang QIAN~(1,2) 1.college of Materials science and Engineering,Southeast University,Nanjing 211189,China 2.Jiangsu Key Lab of Construction Materials,Nanjing 211189,China college of Materials science and Engineering Southeast University Nanjing 211189 China Jiangsu Key Lab of Construction Materials Nanjing 211189 China

The creep characteristics and internal relative humidity(IRH) of concrete with shrinkage reducing admixtures(SRA),poly vinyl alcohol fiber(PVAF) and a mixture of fly ash and slag(MFS) were investigated by the self-made loading *** pore structure was tested,and the relationship of creep and IRH of concrete was *** results indicate that MFS and SRA reduce the total creep and delay the change of ***,the effect of PVAF is contrary,relative to MFS and *** total creep depends largely on drying *** basic creep of concrete is similar,which is significantly influenced by volume fraction of pores whose diameter is between 3.5 nm and 50 nm to the total pore(VP),and IRH of concrete is connected with *** is easy to obtain a good linear relationship predicting the creep of concrete according to the change of IRH.

关键词： modified admixture internal relative humidity total creep drying creep basic creep porosity

Theory and techniques of data mining in CGF behavior modeling

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science China(Information sciences) 2011年第4期54卷 717-731页

作者： YIN YunFei 1,2,GONG GuangHong 2 & HAN Liang 2 1 college of Computer science,Chongqing University,Chongqing 400044,China 2 School of Automation science and Electrical Engineering,Beijing University of Aeronautics and Astronautics,Beijing 100083,China college of Computer science Chongqing University Chongqing China School of Automation science and Electrical Engineering Beijing University of Aeronautics and Astronautics Beijing China

For the large quantity of data,rules and models generated in the course of computer generated forces (CGFs) behavior modeling,the common analytical methods are statistical methods based on the tactical rules,tactical doctrine and empirical ***,from the viewpoint of data mining,we can find many of these analytical methods are also each-and-every different data mining *** this paper,we survey the data mining theory and techniques that have appeared in the course of CGF behavior modeling from the viewpoint of data ***,we redefine and reclassify these theories and techniques according to the research requirements of data mining (the knowledge structure of data mining).We aim to help the CGF investigators to learn the key points and the research methods of the data intelligent processing in the CGF behavior modeling,and thus we can provide the references for the colleagues who are engaged in the research and practice of the CGF behavior modeling by this *** also introduce our ongoing work on the CGF behavior modeling based on data mining.

关键词： CGF CGF behavior modeling data mining theory and techniques

Nuclear Magnetic Resonance Studies on Huwentoxin-Ⅺ from the Chinese Bird Spider Ornithoctonus huwena:15N Labeling and Sequence-specific 1H,15N Nuclear Magnetic Resonance Assignments

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Acta Biochimica et Biophysica Sinica 2006年第7期 457-466页

作者： Kuan PENG~1 Ying LIN~1 Song-Ping LIANG~(1,2*) 1 college of Life science,Peking University,Beijing 100871,China 2 college of Life science,Hunan Normal University,Changsha 410081,China

Huwentoxin-XI purified from the Chinese bird spider Ornithoctonus huwena is a toxin withboth antiprotease activity and potassium channel blocking *** determine its solution structure,huwentoxin-Ⅺ was expressed in a yeast eukaryotic expression system and studied by ***15N labelingstrategy was used to facilitate the process of resonance *** nearly complete sequence-specificassignments of proton and nitrogen resonances were obtained by analyzing a series of two-dimensional（2D）and three-dimensional（3D）spectra,including DQF-COSY,TOCSY,NOESY,15N-1H HSQC,15N-1H HNHA,15N-1H HNHB,15N-1H TOCSY-HSQC and15N-1H NOESY-HSQC *** structure analysis ofhuwentoxin-Ⅺ showed that it mainly contains an N-terminal 310-helix from Thr3 to Arg5 and a C-terminalα-helix from Gln45 to Cys52,plus a triple-stranded antiparallel β-sheet of Glul 8-Asn23,Thr26-Ile31 *** studies provide a solid basis for the final structure determination of huwentoxin-Ⅺ.

关键词： huwentoxin-XI toxin nuclear magnetic resonance 15N labeling sequence-specific assignment

Synergy between Cucumber Mosaic Virus and Zucchini Yellow Mosaic Virus on Cucurbitaceae Hosts Tested by Real-time Reverse Transcription-Polymerase Chain Reaction

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Acta Biochimica et Biophysica Sinica 2007年第6期39卷 431-437页

作者： Rong ZENG~(1,2#), Qiansheng LIAO~(2#), Junli FENG~2, Dingjun LI~1, and Jishuang CHEN~(2*) 1 college of Bio-Safety science Technology, Hunan Agricultural University, Changsha 410128, China, 2 Institute of Bioengineering, Zhejiang Sci-Teeh University, Hangzhou 310018, China college of Bio-Safety science Technology Human Agricultural UniversityChangsha 410128 China Institute of Bioengineering Zhejiang Sci-Tech UniversityHangzhou 310018 China

Cucumber mosaic virus (CMV) and zucchini yellow mosaic virus (ZYMV) are two principal viruses infecting cucurbitaceous crops, and their synergy has been repeatedly observed. In our present work, a real-time reverse transcription-polymerase chain reaction procedure was established to study the accumulation kinetics of these two viruses in single and combined infections at the molecular level. The accumulations of open reading frames (ORFs) for 1a, 2a, 3a and coat protein (CP) of CMV and CP of ZYMV were tested. In the single infection, CMV-Fny ORFs accumulated to their maxima in cucumber or bottle gourd at 14 d post-inoculation (dpi), and gradually declined thereafter. ZYMV-SD CP ORF reached maximal accumulation at 14 and 28 dpi on cucumber and bottle gourd, respectively. However, when coinfected with CMV-Fny and ZYMV-SD, the maximal accumulation levels of all viral ORFs were delayed. CMV-Fny ORFs reached their maxima at 21 dpi on both hosts, and ZYMV-SD CP ORF reached maximal accumulation at 21 and 28 dpi on cucumber and bottle gourd, respectively. Generally, the accumulation levels of CMV-Fny ORFs in the co-infection were higher than those in the single infection, whereas the accumulation of ZYMV-SD CP ORF showed a reverse result.

关键词： cucumber mosaic virus genornic RNA real-time RT-PCR relative quantification synergy zucchini yellow mosaic virus

Near lossless compression of hyperspectral images based on distributed source coding

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science China(Information sciences) 2012年第11期55卷 2646-2655页

作者： NIAN YongJian1,WAN JianWei1,TANG Yi1 & CHEN Bo2 1college of Electronic science and Engineering,National University of Defense Technology,Changsha,410073,China 2college of science,National University of Defense Technology,Changsha,410073,China college of Electronic science and Engineering National University of Defense Technology Changsha China college of science National University of Defense Technology Changsha China

Effective compression technique of on-board hyperspectral images has been an active topic in the field of hyperspectral remote *** order to solve the effective compression of on-board hyperspectral images,a new distributed near lossless compression algorithm based on multilevel coset codes is *** to the diverse importance of each band,a new adaptive rate allocation algorithm is proposed,which allocates rational rate for each band according to the size of weight factor defined for hyperspectral images subject to the target rate *** prediction is introduced for Slepian-Wolf lossless coding and an optimal quantization algorithm is presented under the correct reconstruction of Slepian-Wolf decoder,which minimizes the distortion of reconstructed hyperspectral images under the target *** Slepian-Wolf encoder exploits the correlation of the quantized values to generate the final bit *** results show that the proposed algorithm has both higher compression efficiency and lower encoder complexity than several existing classical algorithms.

关键词： hyperspectral images near lossless compression Slepian-Wolf coding distributed source coding