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Progress and review of the studies on the end-Triassic mass extinction event

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Science china Earth Sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1,2, LU Yuanzheng1,2,3 & XU Daoyi4.1. Research Institute of Petroleum Exploration and Development, beijing 100083, china 2. Key Laboratory of Oil and Gas Reservoir of Petrochina, beijing 100083, china 3. china university of Geosciences, beijing 100083, china 4. Institute of Geology, china Earthquake Administration, beijing 100029, china Research Institute of Petroleum Exploration and Development Beijing China Key Laboratory of Oil and Gas Reservoir of Petrochina Beijing China china university of Geosciences Beijing China Institute of Geology China Earthquake Administration Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. china has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

Quantum threshold group signature

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Science china(Physics,Mechanics & Astronomy) 2008年第10期51卷 1505-1514页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4.1 College of Computer Science and Technology, beijing university of Technology, beijing 100124. china 2 State Key Laboratory of Integrated Services Network, Xidian university, Xi’an 710071, china 3 State Key Laboratory of Information Security (graduate university of Chinese Academy of Sciences), beijing 10004., china 4.State Key Laboratory of Networking and Switching Technology, beijing university of Posts and Tele-communications, beijing 100876, china College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China

In most situations, the signer is generally a single person. However, when the message is written on behalf of an organization, a valid message may require the approval or consent of several persons. Threshold signature is a solution to this problem. Generally speaking, as an authority which can be trusted by all members does not exist, a threshold signature scheme without a trusted party appears more attractive. Following some ideas of the classical Shamir’s threshold signature scheme, a quantum threshold group signature one is proposed. In the proposed scheme, only t or more of n persons in the group can generate the group signature and any t-1 or fewer ones cannot do that. In the verification phase, any t or more of n signature receivers can verify the message and any t-1 or fewer receivers cannot verify the validity of the signature.

关键词： threshold quantum signature trusted party quantum cryptography

Cloning,expression and characterization of a nucleoside diphosphate kinase (NDPK) gene from tobacco

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Progress in Natural Science:Materials International 2007年第8期17卷 906-912页

作者： Zhou Qiyun~(1,2**) Xie Zongming~(1**) Zhang Zhigang~1 Cao Yangrong~1 Zhang jinsong~(1***) Chen Shouyi~(1***) (1.National Key Laboratory of Plant Genomics,Institute of Genetics and Developmental Biology,Chinese Academy of Sciences,beijing100101,china 2.graduate university of Chinese Academy of Sciences,beijing 100039,china) National Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Acad. of Sci. Beijing 100101 China graduate university Chinese Acad. of Sci. Beijing 100039 China

Nucleoside diphosphate kinase (NDPK) is a housekeeping enzyme that maintains the intracellular levels of all (d)NTPs used in biosynthesis except *** we report that a full-length cDNA encoding nucleoside diphosphate kinase (NDPK) was cloned us- ing yeast two-hybrid approach.A tobacco NDPK gene was obtained and designated as ***1 is 704.bp in length and en- codes a putative 16.2 kD protein of 14. amino *** analysis showed that NtNDPK1 is highly homologous to other plant NDPK genes and identified as type I (NDPK1).RNA-gel blot analysis showed that there was no significant difference of NtNDPK1 ex- pression in roots,stems,leaves and *** expression of NtNDPK1 was induced by ABA and PEG and repressed by NaCl,but not significantly affected by Paraquat,wounding and low temperature (4.) treatments,indicating that NtNDPK1 may play a certain role in response to abiotic *** vitro phosphorylation assay demonstrated that NtNDPK1 had autophosphoryLation activity.

关键词： abiotic stress autophosphorylation activity NtNDPK1 tobacco yeast two-hybrid

Community Structure and Seasonal Variation of Soil Arthropods in the Forest-Steppe Ecotone of the Mountainous Region in Northern Hebei,china

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Journal of Mountain Science 2010年第2期7卷 187-196页

作者： ZHU Xinyu GAO Baojia YUAN Shengliang HU Yunchuan Institute of Mountain Hazards and Environment CAS Chengdu 610041 China graduate university of the Chinese Academy of Sciences Beijing 100039 China Hebei North university Zhangjiakou 075000 China Agricultural university ofHebei Baoding 071000 China

Soil fauna have been receiving more and more attention because they play an important role in nutrient ***,there is a lack of information on soil arthropods in the forest-steppe ecotone in the mountainous region of northern Hebei,which makes it difficult to meet the need of protecting biodiversity in this *** arthropod communities were investigated in the forest-steppe ecotone in northern Hebei province to provide basic information on changes in mountain soil fertility,which could promote the development of soil arthropod communities in mountain *** the preliminary identification,a total of 7994.individual soil arthropods were collected,which belonged to 25 groups,6 classes and 24.***,Hymenoptera and Collembola were the dominant groups in the *** number of Acarina was higher than Collembola,and this phenomenon was obviously different from other areas in the same climate *** increased abundance of rare groups in the Forest zone with the richer vegetation,higher arthropod abundance and more substantial litter depth,could be interpreted as a reaction to the suitable soil environment and food *** these rare groups were sensitive to environmental changes,which could be regarded as biotic indicators for evaluating soil *** analysis of community diversity showed that the abundance index (d),the Shannon-Wiener index (H'),the evenness index (J) and the density-group index (DG) were significantly higher in the forest zone,lower in the forest-steppe zone,and lowest in the meadow-steppe *** variations in community composition correlated with changes in average air temperature and precipitation in this *** and individuals of soil arthropod communities in the three zones were present in greater numbers in the middle of the rainy season than in the early or late periods of the rainy season as a *** the same time,seasonal changes in soil arthropod communities from different plots were also

关键词： Soil arthropods Diversity Composition Ecotone Seasonal change

Threshold proxy quantum signature scheme with threshold shared verification

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Science china(Physics,Mechanics & Astronomy) 2008年第8期51卷 1079-1088页

作者： YANG YuGuang1,3,4.& WEN QiaoYan2 1 College of Computer Science and Technology,beijing university of Technology,beijing 100124.china 2 State Key Laboratory of Networking and Switching Technology,beijing university of Posts and Tele-communications,beijing 100876,china 3 State Key Laboratory of Integrated Services Network,Xidian university,Xi’an 710071,china 4.State Key Laboratory of Information Security(graduate university of Chinese Academy of Sciences) ,beijing 10004.,china College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of Information Security (graduate university of Chinese Academy of Sciences) Beijing China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China

A threshold proxy quantum signature scheme with threshold shared verification is proposed. An original signer could authorize a group as its proxy signers. Then only t or more of n persons in the proxy group can generate the proxy signature on behalf of the original signer and any t-1 or fewer ones cannot do that. When the proxy signature needs to be verified,any t or more of n persons belonging to the verification group can verify the message and any t-1 or fewer ones cannot verify the validity of the proxy signature.

关键词： quantum signature threshold proxy quantum group signature threshold shared verification

Threshold quantum secret sharing between multi-party and multi-party

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Science china(Physics,Mechanics & Astronomy) 2008年第9期51卷 1308-1315页

作者： YANG YuGuang1,2,3 & WEN QiaoYan4.1 College of Computer Science and Technology,beijing university of Technology,beijing 100124.china 2 State Key Laboratory of Integrated Services Network,Xidian university,Xi’an 710071,china 3 State Key Laboratory of Information Security (graduate university of Chinese Academy of Sciences),beijing 10004.,china 4.State Key Laboratory of Networking and Switching Technology,beijing university of Posts and Tele-communications,beijing 100876,china College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Integrated Services Network Xidian University Xi’an China State Key Laboratory of Information Security (graduate university of Chinese Academy of Sciences) Beijing China State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing China

A threshold quantum secret sharing (TQSS) scheme between multi-party and multi-party was proposed using a sequence of single photons,which is useful and efficient when the parties of communication are not all present. We described the process of this TQSS scheme and discussed its security. It was shown that entan-glement is not necessary for quantum secret sharing. Moreover,the theoretic effi-ciency was improved to approach 100% as almost all the instances can be used for generating the private key,and each photon can carry one bit of information. This protocol is feasible with the present-day technique.

关键词： threshold quantum secret sharing quantum cryptography single photon multi-party and multi-party

Multiparty simultaneous quantum identity authentication with secret sharing

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Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3 & ZHANG Xing4.5 1 College of Computer Science and Technology,beijing university of Technology,beijing 100022,china 2 State Key Laboratory of Information Security ({4. university of the Chinese Academy of Sciences),beijing 10004.,china 3 School of Science,beijing university of Posts and Telecommunications,beijing 100876,china 4.Institute of Electronic Technology,Information Engineering university,Zhengzhou 4.0004.china 5 Trusted Computing Laboratory,beijing university of Technology,beijing 100022,china College of Computer Science and Technology Beijing University of Technology Beijing China State Key Laboratory of Information Security (graduate university of the Chinese Academy of Sciences) Beijing China School of Science Beijing University of Posts and Telecommunications Beijing China Institute of Electronic Technology Information Engineering University Zhengzhou China Trusted Computing Laboratory Beijing University of Technology Beijing China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

DECISION TREE COMPLEXITY OF GRAPH PROPERTIES

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中国科学院大学学报 1999年第2期 95-99页

作者： Gao Suixiang (Mathematics Department,graduate School university of Science & Technology of china,beijing {4.)

Decision tree complexity is an important measure of computational complexity.A graph property is a set of graphs such that if some graph G is in the set then each isomorphic graph to G is also in the *** P be a graph property on n vertices,if every decision tree algorithm recognizing P must examine at least k pairs of vertices in the worst case,then it is said that the decision tree complexity of P is k .If every decision tree algorithm recognizing P must examine all n(n -1)/2 pairs of vertices in the worst case,then P is said to be elusive .Karp conjectured that every nontrivial monotone graph property is *** this paper,we present some positive results for this *** research the decision tree complexity of graph property in view of algebraic topology and show that if the abstract simplicial complex of a nontrivial monotone graph property P on n vertices has dimension at most n -1( n -2,in another case),then P is elusive

关键词： Computation complexity graph property decision tree algorithm elusive

THE　4.Σ-　STATES　OF　THE　FO　RADICAL

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Chinese Chemical Letters 1996年第5期7卷 475-478页

作者： Ming Bao HUANG (Department of Chemistry, graduate School, Academia Sinica, beijing 100039) Department of Chemistry Graduate School Academia Sinica Beijing 100039

Abstract: For investigating the 4.- 4.- transition in the FO radical to which an observed 268 nm ASE line has been attributed. the potential energy energy of the four lowest-lying 4.2 states of FO have been calculated using the NIRSDCI method. The results indicate that the first 4.- (14.2) and the upper 4.- (4.A2) States are weakly bound and bound states respectively, and the 24.2 and 34.2 States are both repulsive States which are not relevant to the emission. The predicted Te value for the 4.-→4.- transition is 4.62 eV, which is in excellent agreement with the photon energy value (4.63 eV) of the ASE line. The procedure of our MRSDCI calculations for excited states is described in detail, and the previous calculation results for these States are discussed.

关键词： ENERGY EXTRAPOLATION CI CALCULATIONS