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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, guangzhou 510275, china 2. Guangdong Province Key laboratory of Information Security, guangzhou 510275, 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.

Biorthogonal multiple wavelets generated by vector refinement equation

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Science china Mathematics 2007年第7期50卷 1015-1025页

作者： Song LI~(1+) Jun XIAN~2 1 Department of Mathematics,Zhejiang university,Hangzhou 310027,china 2 Department of Mathematics,sun yat-sen university,guangzhou 510275,china 1. Department of Mathematics Zhejiang University Hangzhou 310027 China 2. Department of Mathematics Sun Yat-Sen University Guangzhou 510275 China

Biorthogonal multiple wavelets are generated from refinable function vectors by using the multiresolution analysis. In this paper we provide a general method for the construction of compactly supported biorthogonal multiple wavelets by refinable function vectors which are the solutions of vector refinement equations of the form $$\varphi (x) = \sum\limits_{\alpha \in \mathbb{Z}^s } {a(\alpha )\varphi (Mx - \alpha ), x \in \mathbb{R}^s } ,$$ where the vector of functions ? = (? 1, …, ? r)T is in $(L_2 (\mathbb{R}^s ))^r ,a = :(a(\alpha ))_{\alpha \in \mathbb{Z}^s } $ is a finitely supported sequence of r × r matrices called the refinement mask, and M is an s × s integer matrix such that lim n→∞ M ?n = 0. Our characterizations are in the general setting and the main results of this paper are the real extensions of some known results.

关键词： refinement equation biorthogonal multiple wavelets refinable function vector 42C40 41A10 41A15 41A25

Secure multi-party computation protocol for sequencing problem

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Science china(Information sciences) 2011年第8期54卷 1654-1662页

作者： TANG ChunMing 1,2,SHI GuiHua 1 & YAO ZhengAn 3 1 School of Mathematics and Information Science,guangzhou university,guangzhou 51.006, china 2State Key laboratory of Information Security, Institute of Software Science,Chinese Academy of sciences,Beijing 100080,china 3 School of Mathematics and Computational Science,sun yat-sen university,guangzhou 510275,china 1. School of Mathematics and Information Science Guangzhou University Guangzhou 510006 China2. State Key Laboratory of Information Security Institute of Software Science Chinese Academy of Sciences Beijing 100080 China3. School of Mathematics and Computational Science Sun Yat-Sen University Guangzhou 510275 China

In the field of multi-party computation,an important problem is how to construct an efficient and secure multi-party computation protocol for certain specific *** the present study,we make use of a secret sharing scheme to construct an efficient and secure multi-party computation protocol for sequencing *** protocols are perfectly secure against both a passive adversary that can corrupt at most t (n-1)/2 participants, and an active adversary that can corrupt at most t < n/3 *** simplest sequencing problem is the Millionaires' problem.

关键词： secure multi-party computation sequencing problem secret sharing

Linearly time-varying channel estimation and training power allocation for OFDM/MIMO systems using superimposed training

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Science china(Information sciences) 2011年第7期54卷 1456-1470页

作者： ZHANG Han 1,DAI XianHua 2 & Pan DaRu 1 1 School of Physics and Telecommunication Engineering,South china Normal university,guangzhou 51.006,china 2 Department of Information Science and Technology,sun yat-sen university,guangzhou 510026,china 1. School of Physics and Telecommunication Engineering South China Normal University Guangzhou 510006 China2. Department of Information Science and Technology SUN Yat-sen University Guangzhou 510026 China

We address the problem of estimating the linearly time-varying (LTV) channel of orthogonal frequency division multiplexing (OFDM)/multiple-input multiple-output (MIMO) systems using superimposed training (ST).The LTV channel is modeled by truncated discrete Fourier *** on this model,a two-step approach is adopted to estimate the LTV channel over multiple OFDM *** also present performance analysis of the channel estimation and derive a closed-form expression for the channel estimation *** is shown that the estimation variances,unlike that of the conventional ST-based schemes,approach to a fixed lower-bound as the training length increases,which is directly proportional to information-pilot power *** wireless communication systems with a limited transmission power,we optimize the ST power allocation by maximizing the lower bound of the average channel *** results show that the proposed approach outperforms the frequency-division multiplexed training schemes.

关键词： OFDM/MIMO systems linearly time-varying channel estimation superimposed training training power allocation

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 laboratory of Biocontrol,School of life sciences,sun yat-sen(Zhongshan) university,guangzhou 510275,china 2 State Key laboratory of Plant Genomics,National Centre for Plant Gene Research,Institute of Genetics and Developmental biology,Chinese Academy of sciences,Beijing 100101,china State Key laboratory of Biocontrol School of Life Sciences Sun Yat-sen (Zhongshan) University Guangzhou 510275 China State Key laboratory 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

Molecular characterization and expression analysis of caveolin-1 in pig tissues

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Science china(life sciences) 2008年第7期51卷 655-661页

作者： WANG Chong1,MEI YingJie 1,LI Li 1,MO DeLin 2,LI JiaQi 1,ZHANG Hao 1,TIAN XingGuo 1 &CHEN YaoSheng2 1college of Animal Science,South china Agricultural university,guangzhou 510642,china 2School of life Science,sun yat-sen university,guangzhou 51.006,china 1. college of Animal Science South China Agricultural University Guangzhou 510642 China 2. School of life Science Sun Yat-Sen University Guangzhou 510006 China

Members of the caveolin family played important roles during fundamental cellular processes,such as regulation of cell morphology,migration,and gene expression in muscle *** this study,caveolin-1 (Cav-1),one of the caveolins,was identified from longissimus dorsi muscle of Large Yorkshire pig and Chinese indigenous Lantang pig based on the results of mRNA differential display *** deduced amino acids sequence of the porcine Cav-1 contained a caveolin domain,and was very conservative among different *** Cav-1 mRNA was widely expressed in the eight tissues in this study,including heart,liver,kidney,encephalon,spleen,lung,longissimus dorsi muscle,and back fat, and the highest expression quantity was found in back fat of the two pig *** expression quantity of porcine Cav-1 in back fat and longissimus dorsi muscle of Lantang pig was significantly higher than that of Large Yorkshire(P<0.01,and P<0.05,respectively).These results suggested that the Cav-1 might be a candidate gene for carcass traits,and might provide valuable information for understanding the mechanism of caveolae signaling in fat deposition by using the animal model of pig.

关键词： caveolin family clone expression analysis real-time quantify PCR

Comparative analysis of astaxanthin and its esters in the mutant E1 of Haematococcus pluvialis and other green algae by HPLC with a C30 column

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Science china(life sciences) 2008年第12期51卷 1108-1115页

作者： PENG Juan1, XIANG WenZhou2,1, TANG QuanMing1, sun Ni1, CHEN Feng1,3 & YUAN JianPing 4 1 South china Sea Institute of Oceanology, Chinese Academy of sciences, guangzhou 510301, china 2 Institute of Oceanology, Chinese Academy of sciences, Qingdao 266071, china 3 School of Biological sciences, The university of Hong Kong, Hong Kong, china 4 Institute of Oceanology & college of life sciences, sun yat-sen university, guangzhou 510301, china South china Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510301 China Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 China School of Biological sciences The University of Hong Kong Hong Kong China Institute of Oceanology & college of life sciences Sun Yat-Sen University Guangzhou 510301 China

A gradient reversed-phase high-performance liquid chromatography (HPLC) method using a C30 col-umn was developed for the simultaneous determination of astaxanthin, astaxanthin monoesters and astaxanthin diesters in the green algae Chlorococcum sp., Chlorella zofingiensis, Haematococcus plu-vialis and the mutant E1, which was obtained from the mutagenesis of H. pluvialis by exposure to UV-irradiation and ethyl methanesulphonate (EMS) with subsequent screening using nicotine. The re-sults showed that the contents of total astaxanthins including free astaxanthin and astaxanthin esters ranged from 1.4 to 30.9 mg/g dry biomass in these green algae. The lower total astaxanthin levels (2 mg/g dry biomass) were detected in the green algae Chlorococcum sp. and C. zofingiensis. The higher total astaxanthin levels (>16 mg/g dry biomass) were found in the green alga H. pluvialis and its mutant E1. It is notable that the mutant E1 is found to have considerably higher amounts of total astaxanthin (30.9 mg/g) as compared to the wild strain of H. pluvialis (16.1 mg/g). This indicates that UV-irradiation and EMS compound mutagenesis with subsequent screening using nicotine is an effective method for breeding of a high-producing astaxanthin strain of H. pluvialis. In addition, the green alga C. zofingien-sis had a remarkably higher percentage of astaxanthin diesters (76.3% of total astaxanthins) and a re-markably lower percentage of astaxanthin monoesters (18.0% of total astaxanthins) in comparison with H. pluvialis (35.5% for diesters and 60.9% for monoesters), the mutant E1 (49.1% and 48.1%) and Chlorococcum sp. (18.0% and 58.6%).

关键词： green algae Haematococcus pluvialis mutant astaxanthin HPLC C30 column

Spatio-temporate Expression of P53, Bcl-2 and Fas in the Retina of RD, Rds and C3H Mice

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眼科学报 2000年第3期16卷 158-162页

作者： Ying Chen, Qingjiong ZhangOcular Genetic & Molecular biology, Zhongshan Ophthalmic Center, sun yat-sen university of Medical sciences guangzhou 510060, china Ocular Genetic & Molecular Biology Zhongshan Ophthalmic Center Sun Yat-sen University of Medical Sciences Guangzhou 510060 China

PURPOSE: To investigate the expression status of p53, Fas and bcl-2 in the development of retinal degeneration in C3H, rd and rds mice. METHODS: Expression of p53, Fas and bcl-2 in the retina of rd, rds and C3H mice as well as in normal C3B mice in different periods was examined by immunohistochemical technique. RESULTS: The expression of Fas and p53 was not detected in normal C3B mice. Fas and p53 were expressed in the ganglionic layer in the early stage and then in the inner nuclear layer, while the scale and intense increased in the ganglionic layer. There is no difference of bcl-2 expression between the normal mice and mice with retinal degeneration. CONCLUSION: Fas and p53 may be involved in the retinal cell death in rd, rds, and C3B, but bcl-2 may not. It is unknown why p53 and Fas appeared first in ganglion layer but not in the outer nuclear layer where retinal cells death was noticed in early stage.

关键词：视膜 P53 Bcl Fas 表达视网膜光

Research on Public Participation and Information Publicity in Strategic Environmental Assessment

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 40-46页

作者： Gao Changbo 1,2, Mo Chuangrong 1, Chen Xingeng 1, Zhang Shixi 1 & sun Yanjun 1 1.School of Environmental sciences and Engineering, sun yat-sen university, guangzhou 510275, china 2.Guangdong Industry Technical college, guangzhou 510300, china School of Environmental sciences and Engineering Sun Yat-sen University Guangzhou 510275 China Guangdong Industry Technical college Guangzhou 510300 China

It has been generally recognized that strategic environmental assessment integrates environment and development into decision-making and becomes an important decision-making tool for implementing sustainable development. This paper firstly introduces the relationships of SEA, public participation(PP)and information publicity(IP),then discusses the key parts in enforcing the effective process of PP: They are the methods for how to make sufficient information open (What), when to implement PP (When), who will determinate the public (Who), and how to make the models of PP (How). Six cases are compared and analyzed. At last, ways to improve the effectiveness of PP in china is also presented.

关键词： strategic environmental assessment (SEA) public participation (PP) information publicity (IP) effectiveness