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The lepton flavor violating signal of the extra gauge boson Z′in photon-photon collision at the ILC

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Science china(physics,Mechanics & Astronomy) 2010年第11期53卷 1992-1997页

作者： LIU GuoLi 1,2.1 physics Department,Zhengzhou University,Zhengzhou 450001,china 2.Kavli {2. for Theoretical physics china,chinese academy of Sciences,beijing 100190,china 1. physics Department Zhengzhou University Zhengzhou 450001 China2. Kavli Institute for Theoretical Physics China Chinese Academy of Sciences Beijing 100190 China

The hitherto unconstrained lepton flavor mixings,induced by the new gauge boson Z ,which are the prediction of many new physics models,such as topcolor-assisted technicolor (TC2. models and flavor-universal TC2.models,may lead to the lepton flavor violating productions of τμˉ,τeˉ and μeˉ in photon-photon collision at the proposed International Linear Collider (ILC).Through a comparative analysis of these processes,we find that the better channel to probe the new physics models is the production of τμˉ or τeˉ which occurs at a much higher rate than μeˉ production due to the large mixing angle and the large flavor changing coupling,and may reach the detectable level of the ILC for a large part of the parameter *** the rates predicted by the Standard Model are far below the detectable level,these processes may serve as a sensitive probe for such new physics models.

关键词： new gauge boson Z lepton flavor violating processes photon-photon

Cloning and characterization of interferon stimulated genes Viperin and ISG15,and their promoters from snakehead Channa argus

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Progress in Natural Science:Materials International 2007年第12期17卷 1425-1435页

作者： Jia Weizhang1,2. Zhou Xiuxia1,2. Huang Rong1,2.and Guo Qionglin1(1. institute of Hydrobiololgy, chinese {2. of Sciences, Wuhan 430072. china 2. Graduate University of chinese {2. of Sciences, beijing 100039, china) institute of Hydrobiololgy Chinese Academy of Sciences Wuhan 430072 China Graduate University of chinese academy of Sciences Beijing 100039 China

By suppression subtractive hybridization, rapid amplification of cDNA ends and gene walking methods, interferon stimulated genes (ISGs), Viperin and ISG15, and their promoters have been cloned and characterized from snakehead Channa argus. The Viperin cDNA was found to be 1474 nt and contain an open reading frame (ORF) of 1059 nt that translates into a putative peptide of 352.amino acid (aa). The putative peptide of Viperin shows high identity to that in teleosts and mammals except for the N-terminal 70 aa. The ISG15 cDNA was found to be 758 nt and contain an ORF of 468 nt that translates into a putative peptide of 155 aa. The putative peptide of ISG15 is composed of two tandem repeats of ubiquitin-like (UBL) domains, and a canonical conjugation motif (LRGG) at C-terminal. Viperin and ISG15 promoter regions were characterized by the presence of interferon stimulating response elements (ISRE) and γ-IFN activation sites (GAS). ISRE is a feature of IFN-induced gene promoter and partially overlaps interferon regulatory factor (IRF) 1 and IRF2.recognition sites. GAS is responsible for the γ-IFN mediated transcription. One conserved site for NF-κB was found in the promoter region of Viperin. This is the first report of conservative binding motif for NF-κB in accordance with the consensus sequence (GGGRNNYYCC) among teleost ISG promoters. Moreover, there were also TATA, CAAT and Sp1 transcription factor sites in Viperin and ISG15 promoters. In 5′ untranslated region (UTR), snakehead ISG15 gene contains a single intron, which differs from Viperin gene. The transcripts of Vipeirn and ISG15 mRNA were mainly expressed in head kidney, posterior kidney, spleen and gill. The expression levels in liver were found to increase obviously in response to induction by IFN-inducer poly I∶C.

关键词： interferon interferon stimulated gene (ISG) Viperin ISG15 snakehead (Channa argus).

A new DNA algorithm to solve graph coloring problem

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Progress in Natural Science:Materials International 2007年第6期17卷 733-738页

作者： Jiang Xingpeng1, Li Yin2. Meng Ya3 and Meng Dazhi2.1. National Laboratory of Pattern Recognition,institute of Automation, chinese {2. of Sciences, beijing 100080, china 2. College of Applied Sciences, beijing University of Technology, beijing 10002., china 3. School of Science, beijing institute of Technology, beijing 100081, china) National Laboratory of Pattern Recognition Institute of Automation Chinese Academy of Sciences Beijing 100080 China College of Applied Sciences Beijing University of Technology Beijing 100022 China School of Science Beijing Institute of Technology Beijing 100081 China

Using a small quantity of DNA molecules and little experimental time to solve complex problems successfully is a goal of DNA computing. Some NP-hard problems have been solved by DNA computing with lower time complexity than conventional computing. However, this advantage often brings higher space complexity and needs a large number of DNA encoding molecules. One example is graph coloring problem. Current DNA algorithms need exponentially increasing DNA encoding strands with the growing of problem size. Here we propose a new DNA algorithm of graph coloring problem based on the proof of four-color theorem. This algorithm has good properties of needing a relatively small number of operations in polynomial time and needing a small number of DNA encoding molecules (we need only 6R DNA encoding molecules if the number of regions in a graph is R).

关键词： DNA computing NP-hard problem graph coloring problem.

The deep thermal characteristic of continental margin of the northern South china Sea

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chinese Science Bulletin 2000年第18期45卷 1717-1722页

作者： ZHANG Jian & WANG Jiyang1. Graduate School, University of Science and Technology of china, chinese {2. of Sciences, beijing 100039, china 2. institute of Geology, chinese {2. of Sciences, beijing 10002., china Graduate School University of Science and Technology of China Chinese Academy of Sciences Beijing China institute of Geology Chinese Academy of Sciences Beijing China

Heat flow plays an important role in the study ot thermal structure and thermal evolutionof continental margin of the northern South china Sea. The analysis of heat flow value shows that margin heat flow in the northern South china Sea is relatively high setting, but the percentage of crustal heat flow is lower than 35% in terrestrial heat flow. The terrestrial heat flow exhibited a current of rise from the Northern Continental Margin to the Southern Central Basin. However, the proportion of crustal heat flow in terrestrial heat flow slowly dropped down in the same direction. It is suggested that the main factor causing high heat flow setting is the moving up of hot material from asthenosphere.

关键词： margin of northern South china Sea terrestrial heat flow thermal structures.

Simulating Hydrologic Changes with Climate Change Scenarios in the Haihe River Basin

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Pedosphere 2005年第5期15卷 53-58页

作者： YUAN Fei 1,2. XIE Zheng-Hui1,* 2. LIU Qian1 and XIA Jun 3 1lasg, institute of atmospheric physics, {2. academy of Sciences, beijing 10002. (china). 2.College of Water Resources and Environment, Hohai University, Nanjing 2.0098 (china)3 institute of Geographical Science & Natural Resources, {2. academy of Sciences, beijing 100101 (china) institute of atmospheric {2. chinese academy of Sciences beijing 10002. （china）. 2.College of Water Resources and Environment Hohai University Nanjing 2.0098 （china）3 institute of Geographical Science & Natural Resources beijing 100101 （china）

Climate change scenarios, predicted using the regional climate modeling system of PRECIS (providing regional cli-mates for impacts studies), were used to derive three-layer variable infiltration capacity (VIC-3L) land surface model forthe simulation of hydrologic processes at a spatial resolution of 0.2.° × 0.2.° in the Haihe River Basin. Three climatescenarios were considered in this study: recent climate (1961-1990), future climate A2.(1991-2.00) and future climateB2.(1991-2.00) with A2.and B2.being two storylines of future emissions developed with the Intergovernmental Panel onClimate Change (IPCC) special report on emissions scenarios. Overall, under future climate scenarios A2.and B2. theHaihe River Basin would experience warmer climate with increased precipitation, evaporation and runoff production ascompared with recent climate, but would be still likely prone to water shortages in the period of 2.31-2.70. In addition,under future climate A2.and B2. an increase in runoff during the wet season was noticed, indicating a future rise in theflood occurrence possibility in the Haihe River Basin.

关键词： climate change regional climate modeling system runoff VIC-3L model

SYNTHESIS AND CHARACTERIZATION OF NEW STABILIZERS WITH OPTIMAL MOLECULAR WEIGHT

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chinese Journal of Polymer Science 2001年第4期19卷 341-350页

作者： Jiang-qing Pan institute of Chemistry chinese {2. of Sciences, beijing 100080 china chinese Acad Sci Inst Chem Beijing 100080 Peoples R China

Over 2.x 10(8) tons of polymers are produced every year, and a large portion of polymers faces the degradation problem. There are many effective methods to protect polymers against degradation and the addition of stabilizers to polymer remains the most convenient and effective way of enhancing polymer life and performance. In this article, a series of effective stabilizers with optimal molecular weight (MW), including common, monomeric and polymeric stabilizers (antioxidant and light stabilizer) were synthesized using isocyanation, controlled isocyanation, hydrosilylation, epoxide addition, macroreaction of stabilizing functional compounds and polymerization of monomeric stabilizers. The structure and performance of these new stabilizers were characterized by using IR, NMR, MS, UV-spectra, XPS and elemental analysis. The current development of stabilizer synthesis was also reviewed.

关键词： preparation of stabilizer antioxidant hindered amine light stabilizer isocyanation hydrosilylation

Molecular cloning of growth hormone receptor (GHR) from common carp(Cyprinus carpio L.)and identification of its two forms of mRNA transcripts

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Progress in Natural Science:Materials International 2006年第11期16卷 1156-1163页

作者： SUN Xiaofeng~ 1,2., GUO Qionglin~1**, HU Wei~1, WANG Yaping~1 and ZHU Zuoyan~1(1. State Key Laboratory of Freshwater Ecology and Biotechnology, institute of Hydrobiology, chinese {2. of Sciences, Wuhan 430072. china 2. Graduate School of chinese {2. of Sciences, beijing 100039, china) [a]State key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan China China [b]Graduate School of chinese academy of sciences Beijing China

The cDNA of growth hormone receptor (GHR) was cloned from the liver of 2.year common carp (Cyprinus carpio L.) by reverse transcription-polymerase chain reaction (RT-PCR) and rapid amplification of cDNA end (RACE). Its open reading frame (ORF) of 1806 nucleotides is translated into a putative peptide of 602.amino acids, including an extracellular ligand-binding domain of 2.4 amino acids (aa), a single transmembrane domain of 2. aa and an intracellular signal-transduction domain of 334 aa. Sequence analysis indicated that common carp GHR is highly homologous to goldfish (Carassius auratus) GHR at both gene and protein levels. Using a pair of gene-specific primers, a GHR fragment was amplified from the cDNA of 2.year common carp, a 2.4 bp product was identified in liver and a 32. bp product in other tissues. The sequencing of the products and the partial genomic DNA indicated that the difference in product size was the result of a 97 bp intron that alternatively spliced. In addition, the 32. bp fragment could be amplified from all the tissues of 4-month common carp including liver, demonstrating the occurrence of the alternative splicing of this intron during the development of common carp. Moreover, a semi-quantitative RT-PCR was performed to analyze the expression level of GHR in tissues of 2.year common carp and 4-month common carp. The result revealed that in the tissues of gill, thymus and brain, the expression level of GHR in 2.year common carp was significantly lower than that of 4-month common carp.

关键词： growth hormone receptor (GHR) molecular cloning transcript expression analysis common carp.

Physical aging in Zr_(46.75)Ti_(8.2.)Cu_(7.5)Ni_(10)Be_(2..5) typical bulk metallic glass manifested as enthalpy relaxation

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Science china(physics,Mechanics & Astronomy) 2008年第4期51卷 356-364页

作者： WEN Ping,ZHAO ZuoFeng & WANG WeiHua institute of physics,{2. academy of Sciences,beijing 100080,china 1. institute of physics Chinese Academy of Sciences Beijing 100080 China

Enthalpy recovery is not only an important characteristic of physical aging of glass,but also a good tool to investigate the physical aging. Using differential scanning calorimeter (DSC),the enthalpy recovery of Zr46.75Ti8.2.Cu7.5Ni10Be2..5 bulk metallic glass (BMG) was studied. The typical characteristics of enthalpy recovery of glass including the sub-Tg peak and ‘overshot’ were found in BMG. The evolution of the sub-Tg peak and ‘overshot’ were described by the free volume theory and Hodge’s model,respectively. It was found that the former failed to describe the enthalpy recovery in the BMG,while the latter could give a qualitative explanation. In com-bination with the dynamics in the BMG,the origin of the enthalpy recovery in the BMG was discussed. The results show that BMGs are an ideal material to investi-gate the physical aging. The further understanding of physical aging of BMGs is useful to clarify the nature of glass and improve the application and device of new types of BMGs.

关键词： bulk metallic glass enthalpy recovery physical aging

Simulating the impacts of climate variation and land-cover changes on basin hydrology: A case study of the Suomo basin

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Science china Earth Sciences 2005年第9期48卷 1501-1509页

作者： CHEN Junfeng1,2. LI Xiubin2.& ZHANG Ming2.1. institute of Remote Sensing & GIS, Peking University, beijing 100871,{2. 2. institute of Geographical Sciences and Natural Resources Research, chinese academy of Sciences, beijing 100101,{2. 1. institute of Remote Sensing & GIS Peking University 100871 Beijing China 2. institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing Chin

Impacts of land cover changes on watershed hydrology have been a long-term academic concern with acute dispute. But little attention has been paid to such effects on mesoscale river basins, where the society has a closer link to river hydrology. The present study focuses on a mesoscale river basin, the Suomo Basin that is located on the upper reaches of the Yangtze River. Land covers in the basin in the years 1970, 1986 and 1999 were mapped. A lumped hydrologic model, CHARM, and a distributed hydrologic model, SWAT, were used to model the impacts of both land-cover change and climate variation on river runoff during the past four decades. The results show that the contribution of climate variation to the change of runoff regime makes up 60%―80%, while that of land cover changes only 2.%.

关键词： climate variation, land-cover changes, Suomo Basin, CHARM model, SWAT model.