检索结果-南通市图书馆

A Scenario on the Stepwise Evolution of the Genetic Code

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

genomics,Proteomics & Bioinformatics 2007年第Z1期 143-151页

作者： Jing-Fa Xiao and Jun Yu cas key laboratory of genome sciences and information,beijing institute of genomics,chinese academy of sciences,beijing 100029,china.

It is believed that in the RNA world the operational (ribozymes) and the infor-mational (riboscripts) RNA molecules were created with only three (adenosine,uridine,and guanosine) and two (adenosine and uridine) nucleosides,respectively,so that the genetic code started uncomplicated. Ribozymes subsequently evolved to be able to cut and paste themselves and riboscripts were acceptive to rigor-ous editing (adenosine to inosine); the intensive diversification of RNA molecules shaped novel cellular machineries that are capable of polymerizing amino acids-a new type of cellular building materials for life. Initially,the genetic code,encoding seven amino acids,was created only to distinguish purine and pyrimidine; it was later expanded in a stepwise way to encode 12,15,and 20 amino acids through the relief of guanine from its roles as operational signals and through the recruitment of cytosine. Therefore,the maturation of the genetic code also coincided with (1) the departure of aminoacyl-tRNA synthetases (AARSs) from the primordial translation machinery,(2) the replacement of informational RNA by DNA,and (3) the co-evolution of AARSs and their cognate tRNAs. This model predicts gradual replacements of RNA-made molecular mechanisms,cellular processes by proteins,and informational exploitation by DNA.

关键词： genetic code codon aminoacyl-tRNA synthase GC content

Next-generation sequencing technology:A technology review and future perspective

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china.Life sciences) 2010年第1期53卷 44-57页

作者： ZHOU XiaoGuang1,REN LuFeng1,LI YunTao2,ZHANG Meng1,YU YuDe2 & YU Jun1 1 key laboratory of genome sciences and information,beijing institute of genomics,chinese academy of sciences,beijing 100029,china.2 institute of Semiconductors,chinese academy of sciences,beijing 100083,china key laboratory of genome sciences and information Beijing Institute of Genomics Chinese Academy of Sciences Beijing China institute of Semiconductor Chinese Academy of Sciences Beijing China

As one of the most powerful tools in biomedical research,DNA sequencing not only has been improving its productivity at an exponential growth rate but has also been evolving into a new layout of technological territories toward engineering and physical disciplines over the past three *** this technical review,we look into technical characteristics of the next-generation sequencers and provide insights into their future development and *** envisage that some of the emerging platforms are capable of supporting the USD1000 genome and USD100 genome goals if given a few years for technical *** also suggest that scientists from china.should play an active role in this campaign that will have a profound impact on both scientific research and societal healthcare systems.

关键词： genomics DNA sequencing next generation sequencing technologies sequencer

维普期刊数据库

A two-round honest-verifier zero-knowledge protocol

在线全文

学校读者我要写书评

暂无评论

Science china.information sciences) 2010年第5期53卷 954-963页

作者： LIU HanWu 1,2 & LIN DongDai 1 1 The State key laboratory of information Security, institute of Software, chinese academy of sciences, beijing 100190, china.2 Graduate University of the chinese academy of sciences, beijing 100049, china The State key laboratory of information Security Institute of Software Chinese Academy of Sciences Beijing China Graduate University of the chinese academy of sciences Beijing China

Since the concept of zero-knowledge protocols was introduced, it has attracted a lot of attention and in turn showed significant effect on the development of cryptography, complexity theory and other areas. The round complexity of a zero-knowledge protocol is a very important efficiency consideration, and it is required to be as small as possible. Generally, it is desirable to have zero-knowledge protocols with constant numbers of rounds. Goldreich and Oren proved that only languages in BPP have one-round and two-round zero-knowledge protocols. Moreover, they also showed that only languages in BPP have one-round honest-verifier zero-knowledge protocols. The notion of honest-verifier zero-knowledge protocols is highly non-trivial and fascinating itself, and has many other uses. Thus, the problem as to whether there exist two-round honest-verifier zero-knowledge protocols becomes an important open problem. In this paper, we introduce a new simulation technique and present a two-round honest-verifier zero-knowledge protocol for any language in N P under a standard complexity assumption based on this technique.

关键词： proof system argument system zero-knowledge witness indistinguishability black-box one-way permutation commitment scheme zap

CMQV+:An authenticated key exchange protocol from CMQV

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china.information sciences) 2012年第7期55卷 1666-1674页

作者： LI Hui 1,2 & WU ChuanKun 1 1 State key laboratory of information Security,institute of Software,chinese academy of sciences,beijing 100190,china.2 Graduate University of chinese academy of sciences,beijing 100049,china State key laboratory of information Security Institute of Software Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Ustaoglu presents a secure and efficient key exchange protocol named CMQV,based on the design rationales of HMQV and *** with the latter two protocols,on one hand,CMQV achieves high performance of HMQV,and on the other,it is proven secure in eCK model as NAXOS ***,CMQV enjoys the security proof under gap Diffie-Hellman assumption as indicated by its *** this paper,we propose a variant of CMQV,called CMQV+,which is proven secure under a weaker assumption (*** Diffie-Hellman assumption) in eCK model with random oracles while maintaining the high-performance feature of CMQV as much as possible.

关键词： key exchange eCK model trapdoor-test technique provable security CDH assumption

Induction of chromosomal inversion by integration of T-DNA in the rice genome

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Genetics and genomics 2010年第3期37卷 189-196页

作者： Chuanfeng Zhu,Jiahe Wu,Chaozu He State key laboratory of Plant genomics,institute of Microbiology,chinese academy of sciences,beijing 100101,china State key laboratory of Plant genomics Institute of Microbiology Chinese Academy of Sciences Beijing 100101 China

Transfer DNA （T-DNA） of Agrobacterium tumefaciens integration in the plant genome may lead to rearrangements of host plant chromosomal fragments, including inversions. However, there is very little information concerning the inversion. The present study re- ports a transgenic rice line selected from a T-DNA tagged population, which displays a semi-dwarf phenotype. Molecular analysis of this mutant indicated an insertion of two tandem copies of T-DNA into a locus on the rice genome in a head to tail mode. This insertion of T-DNA resulted in the inversion of a 4.9 Mb chromosomal segment. Results of sequence analysis suggest that the chromosomal inversion resulted from the insertion of T-DNA with the help of sequence microhomology between insertion region of T-DNA and target sequence of the host plant.

关键词： Agrobacterium tumefaciens-mediated transformation (ATMT) T-DNA chromosomal inversion

维普期刊数据库

The correspondence between the concepts in description logics for contexts and formal concept analysis

在线全文

学校读者我要写书评

暂无评论

Science china.information sciences) 2012年第5期55卷 1106-1122页

作者： MA Yue 1,2,SUI YueFei 1 & CAO CunGen 1 1 key laboratory of Intelligent information Processing,institute of Computing Technology,chinese academy of sciences,beijing 100190,china.2 Graduate University of chinese academy of sciences,beijing,china key laboratory of Intelligent information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Formal concept analysis (FCA) and description logic (DL) are meant to be formalizations of concepts.A formal concept in the former consists of its intent and extent,where the intent is the set of all the attributes shared by each object in the extent of the concept,and the extent is the set of all the objects sharing each property in the intent of the concept.A concept in the latter formalization is simply a concept name,the interpretation of which is a subset of a *** consider the correspondence between concepts in both formalizations,a multi-valued formal context must be represented both as a knowledge base and as a model of the DL for contexts,where concepts are decomposed into tuple concepts C,interpreted as a set of tuples and value concepts V,interpreted as a set of attribute-value *** show that there is a difference between the interpretation of concepts R.V /R.C and the Galois connection between the extent/intent of formal concepts in *** to the Galois connection,there should be concepts of the form + R.V and + R.C inter-preted in FCA,and hence the logical language L for DL is extended to be L + together with + as a constructor so that + R.V and + R.C are well-defined ***,according to the interpretation in DL there should be pseudo concepts in FCA so that the interpretation of concepts R.V /R.C is the extent/intent of pseudo *** correspondence between formal concepts and concepts in L +,and between pseudo concepts and concepts in L are presented in this paper.

关键词： description logic formal concept analysis concept attribute/role

Dynamic tree-based authenticated group key exchange protocol

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china.information sciences) 2010年第8期53卷 1591-1602页

作者： LI Hui 1,2 , WU ChuanKun 1 & TENG JiKai 1,2 1 State key laboratory of information Security, institute of Software, chinese academy of sciences, beijing 100190, china.2 Graduate University of chinese academy of sciences, beijing 100049, china State key laboratory of information Security Institute of Software Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

Authenticated group key exchange protocols allow a group of users over a public network to establish a shared secret key for the subsequent cryptographic goals. In this paper, we extend BD-II scheme into a dynamic setting, and propose a tree-based authenticated key exchange protocol which is more suitable for dynamic groups in such as ad hoc networks. Our protocol is proven secure in random-oracle model. Additionally, we analyze the costs of our protocols in both communication and computation terms, and compare its performance with three well-known protocols.

关键词： tree-based group key exchange dynamic provable security

Improved multi-pass fast correlation attacks with applications

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china.information sciences) 2011年第8期54卷 1635-1644页

作者： ZHANG Bin & FENG DengGuo State key laboratory of information Security,institute of Software,chinese academy of sciences,beijing 100190,china State key laboratory of information Security Institute of Software Chinese Academy of Sciences Beijing China

In this paper we propose two new algorithms for multi-pass fast correlation attacks on stream *** first algorithm aims at fast symbol-wise decoding in the circumstances that the noise is not very high and we have little resource for *** second algorithm deals with the practical decoding problem in the high noise and limited keystream *** new algorithms are applicable to arbitrary form LFSR and compare favorably to the previously known algorithms in the scenarios under *** applications,we demonstrate new key recovery attacks on one-level Bluetooth E0 and LILI-128,*** 2 37 -bit keystream and 2 28-byte memory,our attack against one-level E0 needs 2 35.1 *** 2 24-bit keystream and 2 24.5 -byte memory,our attack on LILI-128 has time complexity 2 70.6 operations.

关键词： stream cipher fast correlation attacks linear feedback shift register (LFSR) Bluetooth E0 LILI-128

Security model and modular design of fair authentication key exchange protocols

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china.information sciences) 2010年第2期53卷 278-287页

作者： FENG DengGuo & CHEN WeiDong State key laboratory of information Security, institute of Software, chinese academy of sciences, beijing 100190, china State key laboratory of information Security Institute of Software Chinese Academy of Sciences Beijing China

It is traditionally assumed that the legal two parties in authentication key exchange (AKE) communications are both credible. However, in more and more network applications nowadays, it is often required that such protocols be run under the circumstances where ones do not trust in each other. Therefore, in this paper we propose the idea of fair authentication key exchange (FAKE), which has not only the basic properties of AKE protocols, but also some new properties: the "session proof" embedded in the input of protocols by the customer; and if not revealed, the protocols have the deniability, otherwise the transcript of protocol is binding for the identifications. Such a method is capable of solving the contradiction between protecting privacy and the dissension on network service. Then the security model of FAKE protocols is formulated systematically and a flaw of the security model of current signature schemes proposed by Kudla is also corrected. Finally, a kind of FAKE protocol based on current signature schemes is designed and the mBJM-AK security, conditional deniability and fairness of FAKE protocols are proved in the random oracle model.

关键词： authentication key exchange protocols deniability fairness concurrent signature provable security