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A characterization of solvability for a class of networks

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Science china(Information sciences) 2012年第4期55卷 747-754页

作者： YUAN Chen & KAN HaiBin shanghai Key Lab of Intelligent Information Processing,school of Computer Science,fudan university,shanghai 2.04.3,china 1. shanghai Key Lab of Intelligent Information Processing School of Computer Science Fudan University Shanghai 200433 China

In this paper,we find that Property P can be generalized to characterize the solvability of a kind of networks with any number of sources,thus partially answering the open problem as to whether there are properties similar to Property P to characterize the solvability of some *** an application,for a given integer n,we construct such a solvable network that has no solvable solution if its alphabet size is less than n.

关键词： capacity coding capacity network coding solvability

On the inner radius of univalency by pre-Schwarzian derivative

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Science china Mathematics 2007年第7期50卷 987-996页

作者： Tao CHENG~(1,2+) Ji-xiu CHEN~1 1 school of Mathematical sciences,fudan university,shanghai 2.04.3,china 2 Department of Mathematics,Jiangxi Normal university,Nanchang 330022,china 1. school of Mathematical sciences Fudan University Shanghai 200433 China 2. Department of Mathematics Jiangxi Normal University Nanchang 330022 China

In this paper,the inner radius of univalency of hyperbolic domains by pre-Schwarzian derivative is studied,and some general formulas for the lower bound of the inner radius are established. As their applications,the l... 详细信息

关键词： pre-Schwarzian derivative inner radius of univalency universal Teichmuller space 30C62 30F60

A New Measurement Method for Unbalanced Moments in a Two-axis Gimbaled Seeker

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Chinese Journal of Aeronautics 2010年第1期23卷 117-122页

作者： Yu Shuang,Zhao Yanzheng school of Mechanical Engineering,shanghai Jiaotong university,shanghai 200240,china [a] school of Mechanical Engineering Shanghai Jiaotong University Shanghai 200240 China

This article presents a novel method to measure unbalanced moments in a two-axis gimbaled seeker commonly believed to seviously influence the tracking accuracy and stabilizing capability. This method enables individual measurement of unbalanced moments, and judgment of the seeker＇ s status-balanced or not. Furthermore, an instrument is designed based on this method and calibrated. The effectiveness of the proposed method is validated through a simulation. The experimental results show a satisfied level of accuracy the measurements have. This work forms a basis for the further development of a more stabilized gimbaled seeker with less induced vibration and consumed power.

关键词： gimbaled seeker weight sensors measurement unbalanced

Preparation and characterization of some surface negatively charged residue mutants of cytochrome b_5

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Chinese Science Bulletin 2001年第7期46卷 555-559页

作者： WANG Yunhua, WANG Wenhu, LU Junxia, REN Yi, GU Shaohua, XIE Yi & HUANG Zhongxian1. Chemical Biology Lab, Department of Chemistry, fudan university, shanghai 2.04.3, china 2. Genetic Institute, school of life, fudan university, shanghai 2.04.3, china Chemical Biology Lab Department of Chemistry Fudan University Shanghai China Genetic Institute School of Life Fudan University Shanghai China

Site-directed mutagenesis was used to obtain seven variants of tryptic fragment of bovine liver cytochrome bs (cyt bs), in which the negatively charged residues around the heme exposed edge of cyt bs were replaced by hydropho-bic amino acid alanine. Double-site mutants, triple-site mutants and even quadruple-site mutants were obtained. DNA sequencing and molecular weight measurements of the mutant proteins both confirmed that these site-directed muta-genesises were successfully performed. Spectroelectrochem-istry of these mutant proteins revealed that the apparent redox potentials of these mutant proteins caused a positive shift of 2-10 mV. The global structure of these mutant proteins did not show much difference from that of the wild type cyt bs, providing a solid base for the further study on the roles of the proteins’ surface charges.

关键词： cytochrome bs site-directed mutagenesis negative charge on the protein surface redox potential.

Effects of Citral on Aspergillus flavus Spores by Quasi-elastic Light Scattering and Multiplex Microanalysis Techniques

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 277-283页

作者： Man LUO1,2, Li-Ke JIANG2, Yao-Xiong HUANG3, Ming XIAO4, Bo LI4, and Guo-Lin ZOU1* 1College of life sciences, Wuhan university, Wuhan 430072, china 2College of life sciences, Anhui Agricultural university, Hefei 230036, china 3 Institute of Biomedical Engineering, Ji’nan university, Guangzhou 510632, china 4Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering, the Institute of Biodiversity Science, fudan university, shanghai 2.04.3, china College of life sciences Wuhan UniversityWuhan 430072 China College of life sciences Anhui Agricultural UniversityHefei 230036 China Institute of Biomedical Engineering Ji'nan UniversityGuangzhou 510632 China Ministry of Education Key Laboratory for Biodiversity Science and Ecological Engineering the Institute of Biodiversity Science Fudan UniversityShanghai 200433 China

Citral refined from Litsea cubeba oil has been found to have a strong influence on fungi, especially Aspergillus flavus. Multiplex microanalysis and quasi-elastic light scattering techniques were applied to study the effects of citral on Aspergillus flavus spores from the levels of membrane, organelle and intracellular macromolecule. It was found that citral injured the wall and the membrane of A. flavus spore, resulting in decrease of its elasticity. After entering the cell, citral not only influenced the genetic expression of mitochondrion reduplication and its morphology, but also changed the aggregation of protein-like macromolecules. As a result, cells, organelles and macromolecules lost their normal structures and functions, eventually leading to the loss of germination ability of A. flavus spores. Since Litsea cubeba oil as food additive and antifungal agent is safe and less poisonous, it is important to elucidate the inhibitory mechanisms of Litsea cubeba oil on the germination ability of A. flavus spore.

关键词： citral Aspergillus flavus spore multiplex microanalysis techniques quasi-elastic light scattering technique

Enhancement of naked FIX minigene expression by chloroquine in mice

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Acta Pharmacologica Sinica 2004年第5期25卷 28-33页

作者： Hong-yan CHEN, Huan-zhang ZHU, Bin LU, Xuan XU, Ji-hua YAO, Qi SHEN, Jing-lun XUE1State Key Laboratory of Genetic Engineering, Institute of Genetics,school of life sciences, fudan university, shanghai 2.04.3, china State Key Laboratory of Genetic Engineering Institute of Genetics School of Life Sciences Fudan University Shanghai 200433 China

AIM: To study the effect of chloroquine on the expression of human clotting factor IX (hFIX) in mice. METHODS:Hydrodynamics-based naked DNA plasmid administration was performed by tail vein injection of 10 g of pCMV-hFIX and chloroquine (0, 100, 200, and 500 mol/L) in 2.2 mL of Ringer solution within 6-7 s, the level andstability of hFIX expression, liver damage and toxicity were then examined. RESULTS: The maximum expression ofhFIX level was 4.41.8 mg/L at 8 h after injection, 9.71.6 mg/L at 24 h only existed in 200 mol/L chloroquine-treated animals, which is 3-4 fold higher than that of control (P3 d later. Transaminase level and liver histological study showed the damage of liverwas not related to chloroquine (P>0.05). CONCLUSION: Chloroquine can enhance and sustain exogenous geneexpression in vivo without side effect under our experimental conditions.

关键词： chloroquine factor IX naked plasmids

Optical and acoustic phonon modes confined in gallium phosphide nanoparticles

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Rare Metals 2010年第6期29卷 561-566页

作者： ZHANG Zhaochun and ZHANG Neng school of Material Science and Engineering,shanghai university,shanghai 200072,china school of Material Science and Engineering Shanghai University Shanghai China

The main aim of this paper is to discuss the confinement effects on the optical and acoustic phonon vibrational modes in gallium phosphide（GaP） nanoparticles（cylindric grain）.The Raman scattering from the GaP nanoparticles was *** was found that the red-shifts of the longitudinal optical（LO） mode and transverse optical（TO） mode were 15 cm？1 and 13.8 cm？1,*** is generally accepted that the red-shifts of the optical phonon modes are due to the presence of smaller nanosized particles（～1.2 nm） acting as the nanoclustered building blocks of the GaP *** the low frequency Raman spectrum,a set of Stokes lines with almost the same spacing was clearly *** scattering feature originates from the discrete phonon density of states of the nanoclustered building *** to Lamb＇s vibrational theory,the Raman shift wavenumbers of the spheroidal mode and torsional mode of the lowest energy surface modes for the nanoclustered building blocks were *** agreement can be achieved between the calculated results and the observed scattering *** results indicate that the corresponding Raman peaks are due to scattering from the localized acoustic phonons in the nanoclustered building blocks in the GaP nanoparticles.

关键词： spectroscopy phonon mode Raman scattering gallium phosphide nanoparticles confinement effects

FATOU　PROPERTY　ON　HARMONIC　MAPS　FROM　COMPLETE　MANIFOLDS　WITH　NONNEGATIVE　CURVATURE　AT　INFINITY　INTO　CONVEX　BALLS

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Chinese Annals of Mathematics,Series B 1995年第3期16卷 341-350页

作者： YANG YIHU(Department of Mathematics,fudan university,shanghai 2.04.3, china.) fudan UNIV DEPT MATHSHANGHAI 200433PEOPLES R CHINA

The author considers harmonic maps on complete noncompact manifolds, solves the Dirichlet problem in manifolds with nonnegative sectional curvature out of a compact set, and proves the Fatou theorem for harmonic maps ... 详细信息

关键词： Complete manifold Harmonic map Convex ball Fatou property.

CDS Simulation and Pattern Formation of Phase Separation

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Communications in Nonlinear Science and Numerical Simulation 1998年第4期3卷 233-236页

作者： Zhanaji LIU Men CHENG Jiong RUAN and Shouji CHENG (Department of Mechanics and Engineering Science, fudan university, shanghai 2.04.3,china)(Department of Mathematics, fudan university, shanghai 2.04.3, china) Dept. of Mechanics and Eng. Science Fudan University Shanghai 200433 China Department of Mathematics Fudan University Shanghai 200433 China

Several properties of the generation and evolution of phase separating patterns for binary material studied by CDS model are proposed. The main conclusions are (1) for alloys spinodal decomposition, the conceptions of "macro-pattern" and "micropattern" are posed by "black-and- white graph" and "gray-scale graph" *** find that though the four forms of map f that represent the self-evolution of order parameter in a cell(lattice) are similar to each other in "macro-pattern" , there are evident differences in their micro-pattern, e.g., some different fine netted structures in the blackdomain and the white domain are found by the micro-pattern, so that distinct mechanical and physical behaviors shall be obtained. (2) If the two constitutions of block copolymers are not symmetric (i.e. r ≠ 0.5), a pattern called "grain-strip cross pattern"is discovered,in the 0.43 < r < 0.45.

关键词： lattice gas automata CDS phase separation Pattern formation