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Science China(life sciences) 2010年第4期53卷 462-470页

作者： LI WenSheng & LIN HaoRan state key {2. of {2., Institute of Aquatic Economic Animals and the Guangdong Provincial key {2. for Aquatic Economic Animals, school of life sciences, sun yat-sen university, guangzhou 5102.5, China 1. state key {2. of {2. Institute of Aquatic Economic Animals and the Guangdong Provincial Key Laboratory for Aquatic Economic Animals School of Life Sciences Sun Yat-sen University Guangzhou 510275 China

In teleosts, growth hormone (GH) production is governed by multiple neuroendocrine factors from the hypothalamus and other regulators from the pituitary and peripheral organs. Exploring the principles followed by pituitary somatotropes when differentiating and integrating the signals from these regulators at the cellular and intracellular level is essential for understanding the endocrine regulation network of growth hormone synthesis and secretion in fish. This paper discusses recent advances in the action mechanisms of GH regulation factors, including the neuroendocrine regulators, pituitary level factors and peripheral factors, primarily involved in their receptor systems as well as in post-receptor signal transduction pathways.

关键词： fish growth hormone receptor signal transduction

A provable secure fuzzy identity based signature scheme

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Science China(Information sciences) 2012年第9期55卷 2139-2148页

作者： WANG ChangJi 1,2.1 school of Information Science and Technology,sun {2.-sen university,{2. 5102.5,China 2.Guangdong Province Information Security key laboratory,sun {2.-sen university,{2. 5102.5,China 1. school of Information Science and Technology Sun Yat-sen University Guangzhou 510275 China2. Guangdong Province Information Security Key Laboratory Sun Yat-sen University Guangzhou 510275 China

To use biometrics identities in an identity based encryption system,Sahai and Waters first introduced the notion of fuzzy identity based encryption(FIBE) in *** et *** it to digital signature and introduced the concept of fuzzy identity based signature(FIBS) in 2.08,and constructed an FIBS scheme based on Sahai and Waters's FIBE *** this paper,we further formalize the notion and security model of FIBS scheme and propose a new construction of FIBS scheme based on bilinear *** proposed scheme not only provides shorter public parameters,private key and signature,but also have useful structures which result in more efficient verification than that of Yang et al.'s FIBS *** proposed FIBS scheme is proved to be existentially unforgeable under a chosen message attack and selective fuzzy identity attack in the random oracle model under the discrete logarithm assumption.

关键词： identity based cryptosystem fuzzy identity based encryption fuzzy identity based signature

Computational RNomics:Structure identification and functional prediction of non-coding RNAs in silico

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Science China(life sciences) 2010年第5期53卷 548-562页

作者： ZHENG LingLing & QU LiangHu key laboratory of Gene Engineering of the Ministry of Education,{2. key laboratory for biocontrol,sun yat-sen university,guangzhou 5102.5,China 1. key laboratory of Gene Engineering of the Ministry of Education State Key Laboratory for Biocontrol Sun Yat-sen University Guangzhou 510275 China

The eukaryotic genome contains varying numbers of non-coding RNA(ncRNA) genes."Computational RNomics" takes a multidisciplinary approach,like information science,to resolve the structure and function of ***,we review the main issues in "Computational RNomics" of data storage and management,ncRNA gene identification and characterization,ncRNA target identification and functional prediction,and we summarize the main methods and current content of "computational RNomics".

关键词： non-coding RNA eukaryote computational RNomics

The three-dimensional structure of Infectious flacherie virus capsid determined by cryo-electron microscopy

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Science China(life sciences) 2009年第12期52卷 1186-1191页

作者： XIE Li1,4, ZHANG QinFen2., LU XingMeng3, DAI XinHong2. LI KunPeng2. HONG Jian1,4· & ZHOU XuePing11 Institute of Biotechnology, Zhejiang university, Hangzhou 31002., China 2.state key laboratory of biocontrol,{2., sun yat-sen university, guangzhou 5102.5, China 3 College of Animal sciences, Zhejiang university, Hangzhou 31002., China 4 Center of Analysis and Measurement, Zhejiang university, Hangzhou 31002., China Institute of Biotechnology Zhejiang University Hangzhou 310029 China state key {2. of {2. School of Life Sciences Sun Yat-Sen University Guangzhou 510275 China College of Animal sciences Zhejiang University Hangzhou 310029 China Center of Analysis and Measurement Zhejiang University Hangzhou 310029 China

Cryo-electron microscopy and image reconstruction were used to determine the three-dimensional structure of Infectious flacherie virus (IFV). 5047 particles were selected for the final reconstruction. The FSC curve showed that the resolution of this capsid structure was 18 ·. The structure is a psuedo T=3 (P=3) icosahedral capsid with a diameter of 302.4 · and a single shell thickness of 15 ·. The density map showed that IFV has a smooth surface without any prominent protrude or depression. Comparison of the IFV structure with those of the insect picorna-like virus-Cricket paralysis virus (CrPV)and human picornavirus-Human rhinovirus 14 (HRV 14) revealed that the IFV structure resembles the CrPV structure. The "Rossmann canyon" is absent in both IFV and CrPV particles. The polypeptide topology of IFV VP2. IFV VP3 was predicted and the subunit location at the capsid surface was further analyzed.

关键词： Infectious flacherie virus cryo-electron microscopy three-dimensional structure polypeptide folding

Twisted Ate pairing on hyperelliptic curves and applications

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Science China(Information sciences) 2010年第8期53卷 1528-1538页

作者： ZHANG FangGuo 1,2.1 school of Information Science and Technology, sun yat-sen university,{2., China 2.Guangdong key laboratory of Information Security Technology,{2., China 1. school of Information Science and Technology Sun Yat-Sen University Guangzhou 510275 China2. Guangdong Key Laboratory of Information Security Technology Guangzhou 510275 China

In this paper we show that the twisted Ate pairing on elliptic curves can be generalized to hyperelliptic curves, and give a series of variations of the hyperelliptic Ate and twisted Ate pairings. Using the hyperelliptic Ate pairing and twisted Ate pairing, we propose a new approach to speeding up the Weil pairing computation. For some hyperelliptic curves with high degree twist, computing Weil pairing by our approach may be faster than Tate pairing, Ate pairing, and all other known pairings.

关键词： Ate pairing Weil pairing hyperelliptic curves pairing-based cryptosystems twisted curves

Steganalysis of stochastic modulation steganography

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Science in China(Series F) 2006年第3期49卷 273-285页

作者： HE Junhui1,2.& HUANG Jiwu1,2.1. school of Information Science and Technology, sun yat-sen university,{2., China 2. Guangdong Province key laboratory of Information Security,{2., China 1. school of Information Science and Technology Sun Yat-sen University Guangzhou 510275 China 2. Guangdong Province key laboratory of Information Security Guangzhou 510275 China

Stochastic modulation steganography embeds secret message within the cover image by adding stego-noise with a specific probabilistic distribution. No method is known to be applicable to the estimation of stochastic modulation steganography. By analyzing the distributions of the horizontal pixel difference of images before and after stochastic modulation embedding, we present a new steganalytic approach to accurately estimate the length of secret message in stochastic modulation steganography. The pro- posed method first establishes a model describing the statistical relationship among the differences of the cover image, stego-image and stego-noise. In the case of stegoimage-only steganalysis, rough estimate of the distributional parameters of the cover image＇s pixel difference is obtained with the use of the provided stego-image. And grid search and Chi-square goodness of fit test are exploited to estimate the length of the secret message embedded with stochastic modulation steganography. The experimental results demonstrate that our new approach is effective for steganalyzing stochastic modulation steganography and accurately estimating the length of the secret message.

关键词： information hiding steganography steganalysis stochastic modulation statistical distribution models of difference.

Growth phase-dependent expression of proteins with decreased plant-specific N-glycans and immunogenicity in tobacco BY2.cells

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Science China(life sciences) 2009年第8期52卷 739-746页

作者： YIN BoJiao1,2.ZHENG NuoYan1,2.LI Yin1,TANG SanYuan2.LIANG LiMing1 & XIE Qi1,2.1 state key {2. of {2.,school of life sciences,sun yat-sen(Zhongshan) university,guangzhou {12.,China 2.state key {2. of Plant Genomics,National Centre for Plant Gene Research,Institute of Genetics and Developmental Biology,Chinese Academy of sciences,Beijing 100101,China state key {2. of {2. School of Life Sciences Sun Yat-sen (Zhongshan) University Guangzhou 510275 China state key {2. of Plant Genomics National Centre for Plant Gene Research Institute of Genetics and Developmental Biology Chinese Academy of Sciences Beijing 100101 China

Plants possess some desirable characteristics to synthesize recombinant glycoproteins for pharma-ceutical ***,the mammalian glycoproteins produced in plants are somewhat different from their natural counterparts in terms of *** immunogenicity of plant-specific glyco-epitopes is the major concern in human ***,the distribution of N-glycans in different growth phases of tobacco BY2.cells and their immunogenicity in mice were *** was ob-served that the percentage of β1,2.xylose and α1,3-fucose in proteins of growing cells increased and the corresponding protein extracts caused accelerated immune response in *** on this observation,the recombinant erythropoietin in BY2.cells was expressed and characterized,and Western blot analysis showed that the recombinant erythropoietin contained a relatively small amount of plant-specific glyco-epitopes in the early phase of culture *** study may provide a simple but effective strategy for the production of therapeutic glycoproteins with human-like N-glycan structures in plant hosts to avoid a great allergenic risk.

关键词： BY2 cell,N-glycans,protein expression immunogenicity

High norbornene incorporation in ethylene-norbornene copolymerization with a bis(α-alkyloxoimine) titanium-MAO catalyst

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Science China Chemistry 2010年第8期53卷 1634-1640页

作者： GAO HaiYang1,2.HU Hao1 & WU Qing1,2.1Institute of Polymer Science,school of Chemistry and Chemical Engineering,sun {2.-sen (Zhongshan) university,{2. 5102.5,China 2.7} laboratory for Polymeric Composite and Functional Materials of Ministry of Education sun {2.-sen (Zhongshan) university,{2. 5102.5,China 1. Institute of Polymer Science School of Chemistry and Chemical Engineering Sun Yat-Sen (Zhongshan) University Guangzhou 510275 China2. Key Laboratory for Polymeric Composite and Functional Materials of Ministry of Education Sun Yat-Sen (Zhongshan) University Guangzhou 510275 China

A novel bis(α-alkyloxoimine) titanium(IV) complex was synthesized and used as a catalyst precursor to catalyze homo-and copolymerization of ethylene and *** titanium complex activated with methylalumoxane exhibits good activities for the homopolymerizations of ethylene and norbornene under high temperature to produce high-molecular-weight linear polyethylene and vinyl-type polynorbornene,***-norbornene copolymers with high molecular weight can also be produced by this *** incorporation of norbornene from 0 to 76 mol% in the copolymers can be controlled by varying the charged norbornene.13C NMR analyses show that the microstructures of the ethylene-norbornene copolymers with low norbornene incorporation are predominantly alternated and isolated norbornene units,while those with high norbornene incorporation are random polymers containing long norbornene sequences.

关键词： catalyst ethylene norbornene polymerization copolymerization

Calibration based universal JPEG steganalysis

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Science in China(Series F) 2009年第2期52卷 260-268页

作者： HUANG FangJun1,2.& HUANG JiWu1,2.1 school of Information Science and Technology,sun {2.-sen university,{2. 5102.5,China 2.Guangdong key Lab. of Information Security Technology,sun {2.-sen university,{2. 5102.5,China school of Information Science and Technology Sun Yat-Sen University Guangzhou 510275 China Guangdong key Lab. of Information Security Technology Sun Yat-Sen University Guangzhou 510275 China

For steganalysis of JPEG images, features derived in the embedding domain appear to achieve a preferable performance. However, with the existing JPEG steganography, the minor changes due to the hidden secret data are not easy to be explored directly from the quantized block DCT （BDCT） coefficients in that the energy of the carrier image is much larger than that of the hidden signal. In this paper, we present an improved calibration-based universal JPEG steganalysis, where the microscopic and macroscopic calibrations are combined to calibrate the local and global distribution of the quantized BDCT coefficients of the test image. All features in our method are generated from the difference signal be- tween the quantized BDCT coefficients of the test image and its corresponding microscopic calibrated image, or calculated as the difference between the signal extracted from test image and its corresponding macroscopic calibrated image. The extracted features will be more effective for our classification. Moreover, through using the Markov empirical transition matrices, both magnitude and sign dependencies along row scanning and column scanning patterns existed in intra-block and inter-block quantized BDCT coefficients are employed in our method. Experimental results demonstrate that our proposed scheme outperforms the best effective JPEG steganalyzers having been presented.

关键词： JPEG steganography steganalysis microscopic calibration macroscopic calibration

Non-coding RNAs and the acquisition of genomic imprinting in mammals

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Science China(life sciences) 2009年第3期52卷 195-204页

作者： ZHANG YiJun & QU LiangHu key laboratory of Gene Engineering of the Ministry of Education,{2. key laboratory for biocontrol,sun Yan-sen university,guangzhou 5102.5,China key laboratory of Gene Engineering of the Ministry of Education State Key Laboratory for Biocontrol Sun Yan-Sen University Guangzhou 510275 China

Genomic imprinting,representing parent-specific expression of alleles at a locus,is mainly evident in flowering plants and placental *** imprinted genes,including numerous non-coding RNAs,are located in clusters regulated by imprinting control regions(ICRs).The acquisition and evolution of genomic imprinting is among the most fundamental genetic *** about the transition of mammalian imprinted gene domains from their non-imprinted ancestors,especially recent studies undertaken on the most ancient mammalian clades-the marsupials and monotremes from which model species genomes have recently been sequenced,are of high *** reviewing and analyzing these studies,a close connection between non-coding RNAs and the acquisition of genomic imprinting in mammals is *** evidence comes from two observations accompanied with the acquisition of the imprinting:(i) many novel non-coding RNA genes emerged in imprinted regions;(ii) the expressions of some conserved non-coding RNAs have changed ***,a systematical analysis of imprinted snoRNA(small nucleolar RNA) genes from 15 vertebrates suggests that the origination of imprinted snoRNAs occurred after the divergence between eutherians and marsupials,followed by a rapid expansion leading to the fixation of major gene families in the eutherian ancestor prior to the radiation of modern placental *** in the regulation of imprinted silencing and mediating the chromatins epigenetic modification may be the major roles that non-coding RNAs play during the acquisition of genomic imprinting in mammals.

关键词： genomic imprinting mammals non-coding RNAs