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Zinc up-regulated the expression of the rice metallonthionein gene family and enhanced the zinc tolerance of yeast cells

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Progress in Natural Science:Materials International 2007年第10期17卷 1166-1171页

作者： Xu Yufeng, Zhou Gongke, Li Yiqin and Liu Jinyuan(laboratory of Molecular Biology and Protein Science laboratory of the ministry of education, Department of Biological Sciences and Biotechnology, Tsinghua University, Beijing 100084. {4.) laboratory of Molecular Biology and Protein Science laboratory of the ministry of education Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China

Northern blot and functional complementation assay were employed to analyze the effects of zinc on expression of ten rice metallothionein genes (OsMT-Is) in rice seedlings and the growth of yeast cells transformed with OsMT-Is. Northern blot revealed that in shoots of the rice seedlings treated with different Zn2+concentrations, expression of most members of OsMT-I family was increased, except the type 4.OsMT-Is (OsMT-I-4., 4. and 4.). In roots, Zn2+significantly increased the transcription of OsMT-I-1b and OsMT-I-2c, but reduced the trascription of OsMT-I-1a and OsMT-I-3a. When these ten cDNAs were heterologously expressed in zinc sensitive yeast mutant, all transgenic yeasts showed increased tolerance to Zn2+, and zinc accumulation in these yeast cells also increased. These indicated that OsMT-I family members might respond to extra Zn2+, and they could enhance Zn2+ tolerance of cells by direct binding Zn2+.

关键词： rice metallothionein induced expression Zn2+ tolerance.

Preparation of graphene and TiO2 layer by layer composite with highly photocatalytic efficiency

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Progress in Natural Science:Materials International 2011年第6期21卷 467-471页

作者： Yu-peng ZHANG~1,Jun-jie XU~1,Zhi-hua SUN~1,Chen-zhe LI~1,Chun-xu PAN~(1,2) 1.Key laboratory of Artificial Micro- and Nano-structures of ministry of education, School of Physics and Technology,wuhan University,wuhan 4.0072,china 2.Center for Electron Microscopy,wuhan University,wuhan 4.0072,china [a] Key laboratory of Artificial Micro- and Nano-structures of ministry of education School of Physics and Technology Wuhan University Wuhan 430072 China [b] Center for Electron Microscopy Wuhan University Wuhan 430072 China

A process for fabricating graphene and TiO2layer by layer composite was introduced to improve the photocatalytic activity by controlling the layers,thickness and the mass ratio between graphene and *** graphene oxide（GO） was synthesized from natural graphite powder by the modified Hummers ***-area uniform GO and TiO2thin films were made by a spin-coating process in *** exposure of the TiO2/GO multilayer film to UV light irradiation which allows the reduction of GO to graphene,a novel photocatalytic structure as graphene and TiO2layer by layer composite was *** cross-sectional SEM image showed that a clear layer by layer microstructure with a single layer thickness of graphene or TiO2was in the range of about 50 *** total thickness of the film was around 5μm which was varied according to the layer number of spin coating *** spectra revealed that significant structural changes occurred through UV light *** for methylene blue（MB） exhibited that the layer by layer composite is of higher photocatalytic activity than the pure TiO2layer.

关键词： graphene TiO2 photocatalysis layer by layer composite

Ln_2MO_4.cathode materials for solid oxide fuel cells

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Science china Chemistry 2011年第6期54卷 898-910页

作者： ZHAO Hui, LI Qiang & SUN LiPing Key laboratory of Functional Inorganic Material Chemistry, ministry of education School of Chemistry and Materials Science, Heilongjiang University, Harbin 150080, china 1. Key laboratory of Functional Inorganic Material Chemistry Ministry of Education School of Chemistry and Materials Science Heilongjiang University Harbin 150080 China

One of the major challenges to develop "intermediate temperature" solid oxide fuel cells is finding a novel cathode material, which can meet the following requirements: (1) high electronic conductivity; (2) chemical compatibility with the electrolyte; (3) a matched thermal expansion coefficient (TEC); (4. stability in a wide range of oxygen partial pressure; and (5) high catalytic activity for the oxygen reduction reaction (ORR). In this short review, a survey of these requirements for K2NiF4.type material with the formula Ln2MO4. Ln = La, Pr, Nd, Sm; M = Ni, Cu, Fe, Co, Mn, is presented. The composition-dependent TEC, electrical conductivity and oxygen transport property are considered. The Ln2MO4.materials exhibit improved chemical stability and compatibility with most of the traditional electrolytes. The complete fuel cells integrated with Ln2MO4.materials as cathodes show promising results. Furthermore, these materials are considered as cathodes of protonic ceramic fuel cell (PCFC), and/or anodes of high temperature steam electrolysis (HTSE). First results show excellent performances. The versatility of these Ln2MO4.materials is explained on the basis of structural features and the ability to accommodate oxygen non-stoichiometry.

关键词： intermediate temperature solid oxide fuel cells (ITSOFCs) cathode K2NiF4.type structure oxygen non-stoichiometry

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 100124 China State Key laboratory of Integrated Services Network Xidian University Xi’an 710071 China State Key laboratory of Information Security Graduate University of Chinese Academy of Sciences Beijing 100049 China State Key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 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

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 1. College of Computer Science and Technology Beijing University of Technology Beijing 100124 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 100049 China 2. State Key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 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

Influence of nickel and copper on liquid structure of CuAlNi shape memory alloys

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Chinese Science Bulletin 2002年第1期47卷 85-88页

作者： PAN Xuemin & BIAN XiufangKey laboratory of Liquid Structure and Heredity of Materials, education ministry, Shandong University, Ji’nan 250061, china Key laboratory of Liquid Structure Education Ministry Shandong University Ji'nan 250061 China

Liquid structure of molten pure Cu, Cu-12Al, Cu-12Al-4.i (mass fraction, %) alloys has been investigated using the X-ray diffraction method. It is found that the main peak of the structure factor of pure Cu is symmetrical. In the front of main peak, the curve takes on a shape of parabola, whereas a distinct pre-peak has been found around a scattering vector magnitude of 18.5 nm-1 in the structure factor of the liquid Cu-12Al alloy. This pre-peak increases its inten-sity with the addition of Ni in the liquid Cu-12Al-4.i alloy. The appearance of a pre-peak is a mark of the mediate-range order. Based on Daken-Gurry theory and according to mu-tual interaction between unlike atoms, the analysis of corre-lation between different composition and liquid structure was done: the strong interaction exists between Cu and Ni, so Cu-Al can form strong chemical bond which causes compound-forming behavior. Therefore, the medium-range size clusters can form in melt. The presence of the pre-peak corresponds to these

关键词： Cu-12Al-4.i alloy liquid structure shape memory alloy X-ray diffraction.

Effect of angiotensin II receptor 1 antisense oligodoexynucleotides on physiological and pathophysiological growth of cardiomyocytes

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Acta Pharmacologica Sinica 2004年第5期25卷 19-27页

作者： Ying WANG2, Jin-ming WANG2, Shu-xun Yan3, Ming-jiang LI2,4. Jian-jun LI22Department of Cardiology, Renmin Hospital, wuhan University, wuhan 4.0060, china 3Hubei College of Traditional Chinese Medicine, wuhan 4.0061,china Department of Cardiology Renmin Hospital Wuhan University China Hubei College of Traditional Chinese Medicine China

AIM: To evaluate the role of angiotensin II receptor 1 antisense oligodexynucleotides (AT1R-AS-ODNs) on physi-ological and pathophysiological growth of cardiomyocytes from normotensive rats. METHODS: Cardiomyocyteswere transfected with AT1R-AS-ODNs (200 nmol/L) followed by treatment with or without angiotensin II (1 mol/L).In situ hybridization and Western blot were used for AT1R mRNA and protein detection, respectively. c-Jun N-terminal protein kinase (JNK) activity was characterized by immune complex kinase assay. c-Jun protein expres-sion was examined by immunocytochemistry. DNA content was detected by flow cytometric assay. Atrial natri-uretic factor (ANF) expression was identified by radioimmunoassay. RESULTS: Treatment with AT1R-AS-ODNsfor 24.h resulted in 51.2 % decrease in AT1R mRNA and 60.7 % in protein (P4.JNK and p54.NK wererobustly activated. By 2 h, c-Jun protein expression was increased. By 24.h, angiotensin II caused a markedincrease both in G0/G1 and G2/M DNA content, and increased ANF expression by 1.8-fold. All these were inhibitedby AT1R-AS-ODNs pretreatment. In contrast, sense sequence was ineffective. CONCLUSION: Decrease ofAT1R expression by AS-ODNs did not interfere with normal growth, but protected cardiomyocytes from angio-tensin II-dependent pathophysiological growth.

关键词： antisense oligodeoxynucleotides angiotensin receptors angiotensin II myocardium hypertrophy mitogen-activated protein kinases

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 100124 China State Key laboratory of Integrated Services Network Xidian University Xi’an 710071 China State Key laboratory of Information Security (Graduate University of Chinese Academy of Sciences) Beijing 100049 China State Key laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Beijing 100876 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

Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2)molecule

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2, SUN Weiguo1, HOU Shilin3 & FENG Hao4.1. Institute of Physics, College of Chemical Engineering, Sichuan University, Chengdu 610065, china 2. Institute of Theoretical Physics, Xihua Normal University, Nanchong 637002, china 3. Department of Physics, china Oceanography University, Qingdao 266003, china 4. College of Physics, Sichuan University, Chengdu 610065, china 1. Institute of Physics College of Chemical Engineering Sichuan University 610065 Chengdu China 2. Institute of Theoretical Physics Xihua Normal University 637002 Nanchong China 3. Department of Physics China Oceanography University 266003 Qingdao China 4. College of Physics Sichuan University 610065 Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2 molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.