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Molecular identification of species in Prunus sect. Persica (Rosaceae), with emphasis on evaluation of candidate barcodes for plants

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Journal of Systematics and Evolution 2011年第2期49卷 138-145页

作者： 1,2.Xu QUAN 1 Shi-Liang ZHOU 1 (State Key Laboratory of Systematic and Evolutionary Botany, institute of Botany, chinese academy of sciences, {2. 10009{3.{{3.) 2.(graduate school of the chinese academy of sciences, beijing 100049,{{3.) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate school of the{2. Beijing 100049 China)

Species of Prunus L. sect. Persica are not only important fruit trees, but also popular ornamental and medicinal plants. Correct identification of seedlings, barks, or fruit kernels is sometimes required, but no reliable morphological characters are available. Nowadays, the technique of DNA barcoding has the potential to meet such requirements. In this study, we evaluated the suitability of 11 DNA loci (atpB-rbcL, trnH-psbA, trnL-F, trnS-G, atpF-H, rbcL, matK, rpoB, rpoC1, nad1, and internal transcribed spacer [ITS]) as candidate DNA barcodes for peaches, using samples from 3. populations, covering all the species in sect. Persica. On the whole, the primers worked well in this group and sequencing difficulties were met only in the case of ITS locus. Five loci (rbcL, matK, rpoB, rpoC, and nad1) have very low variation rates, whereas atpB-rbcL, atpF-H, trnH-psbA, trnL-F and trnS-G show more variability. The most variable loci, atpB-rbcL and trnH-psbA, can distinguish three of the five species. Two two-locus combinations, atpB-rbcL+trnL-F and atpB-rbcL+atpF-H, can resolve all five species. We also find that identification powers of the loci are method-dependent. The NeighborNet method shows higher species identification power than maximum parsimony, neighbor joining, and unweighted pair group method with arithmetic mean methods.

关键词： atpB-rbcL DNA barcode Prunus sect. Persica trnL-F.

Formal analysis and design of multi-party fair exchange protocols

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Science in china(Series F) 2006年第2期49卷 155-174页

作者： QING Sihan1,2.3.& LI Gaicheng1,3.1. Engineering Research Center for Information Security Technology, {2. of Software,{3., {2. 100080,{3. 2. {2. Zhongke Ansheng Corporation of Information Technology, {2. 100080,{3. 3. graduate school of the{3., {2. 10003.,{3. Engineering Research Center for Information Security Technology Institute of Software Chinese Academy of Sciences Beijing China beijing Zhongke Ansheng Corporation of Information Technology Beijing China graduate school of the{2. Beijing China

Based on the origin of message items and channel combination between transacting parties, and events and relations among events, this paper presents a concise, precise, and hierarchical model for general fair exchange protocols, formally specifies various security requirements which are able to reflect inherent requirements for fair exchange protocols more rigorously, and partition these security requirements with fine granularity. This work helps analyze, debug, and design multi-party fair exchange protocols more effectively and elaborately,

关键词： fair exchange logical protocol formal model security requirement.

Pretreatment with insulin enhances anticancer functions of 5-fluorou racil in human esophageal and colonic cancer cells

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Acta Pharmacologica Sinica 2007年第5期28卷 721-730页

作者： Ke ZOU~(1,2.,Ji-hang JU~(1,2.,Hong XIE~(1,3.~1 institute of Biochemistry and Cell Biology,Shanghai institutes for Biological {3.,{3. academy of {3.,Shanghai 2.003.,china ~2.graduate school of the chinese academy of sciences,{12.,{13.,china institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai China graduate school of the{2. Beijing China

Aim:To investigate the effects of insulin on enhancing 5-fluorouracil (5-FU) anti-cancer functions and its mechanisms in the human esophageal cancer cell line(Eca 109) and human colonic cancer cell line (Ls-174-t).Methods:The effect ofinsulin/5-FU combination treatment on the growth of Eca 109 and Ls-174-t cellswas evaluated by 3.(4,5-dimethylthiazol-2.yl)-2.5-diphenyl-tetrazolium bromide(MTT) *** insulin treatment or insulin/5-FU treatment,cell cycle distri-bution of both cell lines was analyzed by flow *** blot assay wasused to assess the expression of caspase-3.and thymidylate synthase (TS).Apoptosis was detected by flow cytometry,DNA fragmentation assay,and termi-nal transferase dUTP nick end labeling assay (TUNEL).Moreover,the changes of5-FU uptake after insulin pretreatment were detected by HPLC assay and Westernblot ***:We found that insulin enhanced the inhibitory effect of 5-FU on cell proliferation when Eca 109 cells and Ls-174-t cells were pretreated withinsulin for the appropriate *** increased the cell number of the S phaseand the uptake of ***/5-FU treatment enhanced apoptosis of tumor cellsand upregulated the expression of cleaved caspase-3.compared with 5-FU ***,insulin/5-FU treatment induced the changes of free TS and the TSternary complex level compared with 5-FU treatment in Eca 109 and Ls-174-t ***:These data suggest that insulin enhances anticancer functions of 5-FU when it is treated before 5-FU for the appropriate time in human esophagealand colonic cancer cell lines.

关键词： apoptosis cell cycle 5-fluorouracil insulin

Recent advances in the data analysis method of functional magnetic resonance imaging and its applications in neuroimaging

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Progress in Natural Science:Materials International 2006年第8期16卷 785-795页

作者： TIAN Jie, YANG Lei and HU Jin (institute of Automation, chinese academy of sciences, {2. 100080,{{3. graduate school of chinese academy of sciences, {2. 1000{3.,{{3.) institute of Automation Chinese Academy of Sciences Beijing 100080 China graduate school of{2. Beijing 100039 China

Functional magnetic resonance imaging (fMRI) has opened a new area to explore the human brain. The fMRI can reveal the deep insights of spatial and temporal changes underlying a broad range of brain function, such as motor, vision, memory and emotion, all of which are helpful in the clinical investigation. In this paper, we introduce some recent-developed algorithms for fMRI signal detection such as model-driven method (general linear model, deconvolution model, non-linear model, etc. ) and data-driven method (principle component analysis, independent component analysis, self-organization mapping, clustered constrained non-negative matrix factorization, etc. ). We also propose several important applications of neuroimaging and point out their shortcomings and future perspectives.

关键词： fMR1 data analysis neuroimaging.

Structure of augmentation quotients of finite homocyclic abelian groups

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Science china Mathematics 2007年第9期50卷 1280-1288页

作者： Guo-ping TANG school of Mathematical sciences,{2. University of{{3.,beijing 100049,china school of Mathematical sciences Graduate University of Chinese Academy of Sciences Beijing China

Let G be a finite abelian group and its Sylow p-subgroup a direct product of copies of a cyclic group of order p r , i.e., a finite homocyclic abelian group. Let Δ n (G) denote the n-th power of the augmentation ideal Δ(G) of the integral group ring ?G. The paper gives an explicit structure of the consecutive quotient group Q n (G) = Δ n (G)/Δ n+1(G) for any natural number n and as a consequence settles a problem of Karpilovsky for this particular class of finite abelian groups.

关键词： integral group ring augmentation ideal consecutive quotient of augmentation ideal 16S3. 2.C05

The biomarkers of 2.6,10,15, 19-pentamethylicosenes and their carbon isotopic composition in the sediments from the Gulf of Mexico

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chinese Science Bulletin 2006年第14期51卷 1736-1740页

作者： SONG Zhiguang1,2.& WANG Cuiping1,3.. State Key Laboratory of Organic Geochemistry, Guangzhou institute of Geochemistry,{2., Guangzhou 510640,{3. 2. Guangzhou Research Center of Gas Hydrate,{2., Guangzhou 510640,{3. 3. graduate school of{2., beijing 10003.,{3. State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China Guangzhou Research Center of Gas Hydrate Chinese Academy of Sciences Guangzhou China graduate school of{2. Beijing China

A group of 2.6,10,15,19-pentamethyli- cosenes (PMIΔ) containing 1―5 unsaturated double bonds has been identified in the sea floor sediments from the Gulf of Mexico at the Green Canyon 2.0} *** PMIΔ compounds are distributed between nC2. and nC2. on the mass chromatogram of aliphatic fraction. Their δ 13. values are very much depleted in 13. and in the range of ?86.7‰ to ?115.5‰, whereas the δ 13. values of companion n-alkanes range from ?2..4‰ to ?3..6‰. These unsaturated PMIΔ com-pounds are typical biomarkers derived from the an-aerobic oxidation of methane mediated by meth-ane-oxidizing archaeal bacteria and indicative of the gas seeps or even the occurrence of gas hydrates in the deep sea sediments.

关键词：生物标志墨西哥湾沉积物 PMIA 天然气水化物

Mechanism and Defense on Malicious Code

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Wuhan University Journal of Natural sciences 2005年第1期10卷 83-88页

作者： WEN Wei-ping 1,2.3. QING Si-han 1,2.3.1. {2. of Software, the{3., {2. 100080,{3. 2.Engineering Research Center for Information Security Technology, the{3., {2. 100080,{3. 3.graduate school of the{3., {2. 100080,{3. institute of Software the Chinese Academy of Sciences Beijing China Engineering Research Center for Information Security Technology the Chinese Academy of Sciences Beijing China graduate school of the{2. Beijing China

With the explosive growth of network applications, the threat of the malicious code against network security becomes increasingly serious. In this paper we explore the mechanism of the malicious code by giving an attack model of the malicious code, and discuss the critical techniques of implementation and prevention against the malicious code. The remaining problems and emerging trends in this area are also addressed in the paper.

关键词： malicious code attacking model mechanism defense system security network security

The relation between black hole masses and Lorentz factors of the jet components in blazars

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Research in Astronomy and Astrophysics 2009年第3期9卷 293-301页

作者： Ming Zhou1,2.3.and Xin-Wu Cao1,2.1 Shanghai Astronomical Observatory, chinese academy of sciences, Shanghai 2.003.,{3. 2.Joint {2. for Galaxy and Cosmology (JOINGC) of SHAO and USMC, Shanghai 2.003.,{3. 3.graduate school of the chinese academy of sciences, beijing 100049,{3. Shanghai Astronomical Observatory Chinese Academy of Sciences Shanghai 200030 China Joint institute for Galaxy and Cosmology (JOINGC) of SHAO and USMC Shanghai 200030 China graduate school of the{2. Beijing 100049 China

We explore the relationship between black hole mass (MBH) and the motion of the jet components for a sample of blazars. The Very Long Baseline Array (VLBA) 2.cm Survey and its continuation: Monitoring of Jets in active galactic nuclei (AGNs) with VLBA Experiments (MOJAVE) have observed 2.8 radio-loud AGNs, of which 146 blazars have reliable measurements of their apparent velocities of the jet components. We calculate the minimal Lorentz factors for these sources from their measured apparent velocities, and their black hole masses are estimated with their broad-line widths. A sig- nificant intrinsic correlation is found between black hole masses and the minimal Lorentz factors of the jet components. The Eddington ratio is only weakly correlated with the min- imal Lorentz factor, which may imply that the Blandford-Znajek (BZ) mechanism may dominate over the Blandford-Payne (BP) mechanism for the jet acceleration (at least) in blazars.

关键词： black hole physics — galaxies: active — galaxies: jets — galaxies: nuclei

Characteristics and geological significance of olivine xenocrysts in Cenozoic volcanic rocks from western Qinling

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Progress in Natural Science:Materials International 2006年第12期16卷 1300-1306页

作者： SU Benxun~ 1,2.**, ZHANG Hongfu~1, XIAO Yan~ 1,2.and ZHAO Xinmiao~ 1,2.(1. State Key Laboratory of Lithospheric Evolution, institute of Geology and geophysics,{2., {{3. 10002., china 2. graduate school of{2., {{3. 1000{3., china) State Key Laboratory of Lithospheric Evolution Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China graduate school of{2. Beijing 100039 China

Cenozoic volcanic rocks from the Haoti, Dangchang County of the western Qinling Mountains, contain a few clearly-zoned olivines. These olivines are relatively big in grain sizes and usually have cracks or broken features. Their cores have similar compositions （Mg#=90.4-91.0） to those for the peridotitic xenoliths entrained in host volcanic rocks and their rims are close to the compositions of olivine phenocrysts （Mg#=85.5-81.9）. The CaO contents in these zoned olivines are lower than 0.1%. These features demonstrate that the clearly-zoned olivines are xenocrysts and disaggregated from mantle peridotites. The zoned texture was the result of the interaction between the olivine and host magma. Available data show that the volcanic rocks would have been derived from the mantle source metasomatized by subducted hydrathermally-altered oceanic crust. The formation of these Cenozoic volcanic rocks was perhaps related to the rapid uplift of the Tibetan Plateau.

关键词： Western Qinling Dangchang Haoti Cenozoic volcanic rocks olivine xenocrysts zoned texture.