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Continuous wavelet transform and discrete multi-resolution analysis of surface fluxes and atmospheric stability

Progress in Natural Science:Materials International 2006年第4期16卷 403-409页

作者： JIANG Zhaoyang, YU Qiang, WANG Tianduo, SUN Xiaomin and ZHANG Renhua shanghai institute of Plant Physiology and Ecology, chinese academy of sciences, shanghai 200032, china institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, china [a]shanghai institute of Plant Physiology and Ecology Chinese Academy of Sciences Shanghai China [b]institute of Geograhpic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China

Variations of land surface fluxes of sensible heat (H), latent heat (LE), and CO2(F-CO2) obtained from the eddy-co-variance measurements above a winter wheat field from March 30 to April 24, 2001 have been studied at scales ranging from 10 minutes to days. Wavelet transform is used in the analysis of land surface fluxes and atmospheric stability (ξ) calculated from the measurements to reveal the changes in land surface fluxes in hours to days scales. The main results are: (1) Concise and compact information about the fluxes, net radiation (Rn), temperature ( T) and ξ in the scale-time domain are extracted from the data by continuous wavelet analysis, and 1 day, 0.5 day and short-period (shorter than 0.5 day) components are revealed. Continuous wavelet coefficients can be used to characterize periodic components of changes in fluxes and ξ. (2) Discrete-time multi-resolution analysis can be used to concentrate total energy variance of time series of the measurements to a small number of coefficients, plotting the relative energy distribution to get several meaningful characteristics of the data. (3) Under neutral atmospheric conditions, the relative energy distributions of the Haar multi-resolution analysis of the three non-dimensional coefficients ( T/T* , q/q * and c/c * ) display clear similarities.

关键词： atmospheric stability flux continuous wavelet transform multi-resolution wavelet analysis.

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Synthesis of Peptoid Nucleic Acid with Thymine as Nucleic Base

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chinese Chemical Letters 2000年第9期11卷 771-774页

作者： Yun WU Jie Cheng XU shanghai institute of Organic Chemistry, chinese academy of sciences, shanghai 200032 chinese Acad Sci Shanghai Inst Organ Chem Shanghai 200032 Peoples R China

The synthesis of peptoid nucleic acid bearing thymine as nucleobase has been achieved. This modified oligonucleotide showed good hybridization with DNA.

关键词： peptoid peptide nucleic acid solid phase synthesis thymine

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Rational redesign of inhibitors of furin/kexin processing proteases by electrostatic mutations

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Acta Pharmacologica Sinica 2004年第12期25卷 146-152页

作者： Xiao-hui CAI, Qing ZHANG, Da-fu DING2 Key Laboratory of Proteomics, institute of Biochemistry and Cell Biology, shanghai institutes for Biological sciences, chinese academy of sciences, Graduate School of the chinese academy of sciences, shanghai 200031, china Key Laboratory of Proteomics Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of Sciences Shanghai 200031 China

AIM: To model the three-dimensional structure and investigatethe interaction mechanism ofthe proprotein convertase furin/kexin and their inhibitors (eglin c mutants). METHODS: The three-dimensional complex structures of furin/ kexin with its inhibitors, eglin c mutants, were generated by modeller program using the newly published X-ray crystallographical structures of mouse furin and yeast kexin as templates. The electrostatic interaction energy of each complex was calculated and the results were compared with the experimentally determined inhibition con- stants to find the correlation between them. RESULTS: High quality models of furin/kexin-eglin c mutants were obtained and used for calculation of the electrostatic interaction energies between the proteases and their inhibitors. The calculated electrostaticenergies of interaction showeda linear correlation to the experimental inhibition constants. CONCLUSION: The modeled structures give good explanations of the specificity of eglin c mutants to furin/ kexin. The electrostatic interactions play important roles in inhibitory activity of eglin c mutants to furin/kexin. The results presented here provided quantitative structural and functional information concerning the role of the charge- charge interactions in the binding of furin/kexin and their inhibitors.

关键词： furin kexin eglin c drug design electrostatic mutation

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Simulations for optimization of SSRF BPM

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Nuclear Science and Techniques 2003年第4期14卷 222-225页

作者： YANG Nuo, LIU Gui-Min (shanghai institute of Applied Physics, the chinese academy of sciences, shanghai 201800) shanghai institute of Applied Physics the Chinese Academy of Sciences 上海 201800

The wake field, impedance and output signal for SSRF BPM have been calculated and analyzed by us-ing the numerical simulation code of MAFIA. The narrow-band impedance of BPM arising from formation of reso-nance in its cavity like structure either is harmful to beam or limits the performance of BPM itself, and should be re-duced to tolerable levels. The calculated results show that there are three main peaks in the impedance spectrum ofthe SSRF BPM prototype, and two of which are above the limit. After lots of simulations for different shapes of theBPM button, a new structure of SSRF BPM have been found, and there is only one main peak, which is under thelimit, in the impedance spectrum. Its output signal also meets the requirement.

关键词：数值模拟耦合阻抗 BPM 上海同步加速器辐射装置 SSRF 束定位监视器 MAFIA模型

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Directional migration of leukocytes: their pathological roles in inflammation and strategies for development of anti-inflammatory therapies

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Cell Research 2001年第2期11卷 85-88页

作者： GENG JIAN Guo institute of Biochemistry and Cell Biology, shanghai institutes for Biological sciences, chinese academy of sciences, 320 Yue Yang Road, shanghai 200031, china institute of Biochemistry and Cell Biology Chinese Academy of Sciences Shanghai. jggeng@***

Directional migration of leukocytes is indispensable to innate immunity for host defense. However, recruitment of leukocytes to a site of tissue injury the constitutes a leading cause for inflammatory responses. Mechanistically, it involves a cascade of cellular events precisely regulated by temporal and spatial present tation of a repertoire of molecules in the migrating leukocytes and their surroundings (microenvironments). Here I will summarize the emerging evidence that has shed lights on the underlying molecular mechanism for directional migration of leukocytes, which has guided the therapeutical development for innovative anti-inflammatory medicines.

关键词： Directional cell migration leukocytes inflammation therapy.

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Synthesis of O-(2-[^(18)F]fluoroethyl)-L-tyrosine and its biological evaluation in B16 melanoma-bearing mice as PET tracer for tumor imaging

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Science china Chemistry 2007年第2期50卷 276-283页

作者： WANG MingWei,YIN DuanZhi,LI ShiQiang & WANG YongXian Radiopharmaceutical Centre,shanghai institute of Applied Physics,chinese academy of sciences,shanghai 201800,china 1. Radiopharmaceutical Centre Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China

O-(2-[18F]fluoroethyl) -L-tyrosine([18F]FET) ,a fluorine-18 labeled analogue of tyrosine,has been syn-thesized and biologically evaluated in tumor-bearing mice. The whole synthesis procedure is com-pleted within 50 min. The radiochemical yield is about 40%(no decay corrected) and radiochemical purity more than 97% after simplified solid phase extraction. [18F]FET shows rapid,high uptake and long retention in the tumor as well as low uptake in the brain. The ratios of tumor-to-muscle(T/M) and tumor-to-blood(T/B) of [18F]FET are similar to those of [18F]FDG,but the ratios of tumor-to-brain(T/Br) are 2-3 times higher than that of [18F]FDG. Autoradiography of [18F]FET demonstrates a remarkable accumulation in melanoma with high contrast. It appears to be a probable competitive candidate for melanoma imaging with PET.

关键词： [18F]FET [18F]FDG PET imaging melanoma autoradiography

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On the Formability of Some Metastable Alloy Phases

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Journal of Materials Science & Technology 1994年第1期10卷 23-26页

作者： Bo TANG Deshan KANG Pei QING Weiming ZHANG and Nianyi CHEN(shanghai institute of Metallurgy, chinese academy of sciences, shanghai, 2.0050, china) shanghai Inst of Metallurgy Shanghai China

Pattern recognition and neural network methods have been used to investigate the formability of metastable alloy phases, It has been found that some chemi cal bond parameters Such as valence electron number, electronegativity and metallic radii of cor-nponent elements are the dominating fac tors affecting metastable alloy phase formation. Some semi-empirical rules found in this way may be useful for the construction of expert system for materials design.

关键词： Figure Cd Ni On the Formability of Some Metastable Alloy Phases Chen Pb Sn Ta

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Synthesis and Characteristics of an Aspartame Analogue,L-Asparaginyl L-3-Phenyllactic Acid Methyl Ester

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Acta Biochimica et Biophysica Sinica 2004年第6期36卷 385-389页

作者： Hu TAO1, Da-Fu CUI1, and You-Shang ZHANG1,2* 1institute of Biochemistry and Cell Biology, shanghai institutes for Biological sciences, chinese academy of sciences, Graduate School of the chinese academy of sciences, shanghai 200031, china institute of Protein Research, Tongji University, shanghai 200031, china institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Graduate School of the Chinese Academy of SciencesShanghai 200031 China institute of Protein Research Tongji UniversityShanghai 200031 China

An aspartame analogue, L-asparaginyl L-3-phenyllactic acid methyl ester was synthesized with aspartic acid replaced by asparagine and peptide bond replaced by ester bond. The aspartic acid of aspartame could be replaced by asparagine as reported in the literature. In this analogue, the hydrogen of amide group could still form a hydrogen bond with the oxygen of ester bond and the ester bond was isosteric with peptide bond. However, the product was not sweet, showing that the peptide bond could not be replaced by ester bond. The peptide C-N bond behaves as a double bond that is not free to rotate and the C, O, N and H atoms are in the same plane. The replacement of peptide bond by ester bond destroyed the unique conformation of peptide bond, resulting in the loss of sweet taste.

关键词： artificial sweetener aspartame derivative peptide bond

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Cytotoxicity of carbon nanotubes

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Science china Chemistry 2008年第11期51卷 1021-1029页

作者： ZHU Ying1,2 & LI WenXin1 1 Laboratory of Nano-biology and Medicine, shanghai institute of Applied Physics, chinese academy of sciences, shanghai 201800, china 2 Graduate School of chinese academy of sciences, Beijing 100049, china 1. Laboratory of Nano-biology and Medicine Shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China 2. Graduate School of chinese academy of sciences Beijing 100049 China

With large-scale production and application at large scale, carbon nanotubes (CNTs) may cause ad-verse response to the environment and human health. Thus, study on bio-effects and safety of CNTs has attracted great attention from scientists and governments worldwide. This report briefly summa-rizes the main results from the in vitro toxicity study of CNTs. The emphasis is placed on the descrip-tion of a variety of factors affecting CNTs cytotoxicity, including species of CNTs, impurities contained, lengths of CNTs, aspect ratios, chemical modification, and assaying methods of cytotoxicity. However, experimental information obtained thus far on CNTs' cytotoxicity is lacking in comparability, and some-times there is controversy about it. In order to assess more accurately the potential risks of CNTs to human health, we suggest that care should be taken for issues such as chemical modification and quantitative characterization of CNTs in cytotoxicity assessment. More importantly, studies on physical and chemical mechanisms of CNTs' cytotoxicity should be strengthened; assaying methods and evaluating criteria characterized by nanotoxicology should be gradually established.

关键词： carbon nanotubes (CNTs) cell bio-security

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TeO_(x) Thin Films for Write-Once Optical Recording Media

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Journal of Materials Science & Technology 2004年第6期20卷 678-680页

作者： Qinghui LI, Donghong GU and Fuxi GANResearch Laboratory for High Density Optical Storage, shanghai institute of Optics and Fine Mechanics, chinese academy of sciences, shanghai 201800, china Lab. of High Density Optical Storage Inst. of Optics and Fine Mech. Chinese Acad. of Sci. Shanghai 201800 China

TeO_x thin films were prepared by vacuum evaporation of TeO_2 powder. Structural characteristic and surface mor-phology of the as-deposited films was analyzed by using X-ray photoelectron spectroscopy, transmission electron microscopy, X-ray diffractometer and atomic force microscopy. It was found that the films represented a two component system comprising Te particies dispersed in an amorphous TeO2 matrix. The dispersed Te particies were in a crystalline state. The TeOx films showed a finely granular structure and a rough surface. Results of the statie recording test showed that the TeO_x films had good writing sensitivity for short-wavelength laser beam (514.5 nm). Primary results of the dynamic test at 514.5 nm were also reported. The TeO_x films were suitable for using as a blue-green wavelength high density optical storage medium.

关键词： TeO_x thin film Statie recording test Dynamic test High density optical storage

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