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^(40)Ar/^(39)Ar chronology and geochemistry of high-K volcanic rocks in the Mangkang basin, Tibet

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Science china Earth sciences 2005年第1期48卷 1-12页

作者： ZHANG Huihua, HE Huaiyu, WANG Jianghai & XIE Guanghong guangzhou Institute of Geochemistry, Chinese Academy of sciences, guangzhou 510640, china Institute of Geology and Geophysics, Chinese Academy of sciences, Beijing 100029, china college of life sciences, sun yat-sen univer.ity, guangzhou 510275, china Chinese Academy of sciences Guangzhou Institute of Geochemistry Guangzhou China Chinese Academy of sciences Institute of Geology and Geophysics Beijing China college of life sciences Sun Yat-Sen University Guangzhou China

Our two newly obtained high-quality 40Ar/39Ar ages suggest that the high-K volcanic rocks of the Lawuxiang Formation in the Mangkang basin, Tibet were formed at 33.5 ( 0.2 Ma. The tracing of elemental and Pb-Sr-Nd isotopic geochemistry indicates that they were derived from an EM2 enriched mantle in continental subduction caused by transpression. Their evidently negative anomalies in HFSEs such as Nb and Ta make clear that there is an input of continental material into the mantle source. The high-K rocks at 33.5 ( 0.2 Ma in the Mangkang basin may temporally, spatially and compositionally compare with the early one of two-pulse high-K rocks in eastern Tibet distinguished by Wang J. H. Et al., implying that they were formed in the same tectonic setting.

关键词： Cenozoic high-K volcanic rocks, 40Ar/39Ar chronology, Mangkang basin, Tibet.

Bacterial Phosphoproteomic Analysis Reveals the Correlation Between Protein Phosphorylation and Bacterial Pathogenicity

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Genomics,Proteomics & Bioinformatics 2011年第Z2期 119-127页

作者： Ruiguang Ge and Weiran Shan laboratory of integr.tive Biosciences, college of life sciences, sun yat-sen univer.ity, guangzhou 510275, china

Increasing evidence shows that protein phosphorylation on serine, threonine and tyrosine residues is a major regulatory post-translational modification in the bacteria. This review focuses on the implications of bacterial phosphoproteome in bacterial pathogenicity and highlights recent development of methods in phosphoproteomics and the connectivity of the phosphorylation networks. Recent technical developments in the high accuracy mass spectrometry have dramatically transformed proteomics and made it possible the characterization of a few exhaus- tive site-specific bacterial phosphoproteomes. The high abundance of tyrosine phosphorylations in a few bacterial phosphoproteomes suggests their roles in the pathogenicity, especially in the case of pathogen-host interactions; the high abundance of multi-phosphorylation sites in bacterial phosphoprotein is a compensation of the relatively small phosphorylation size and an indicator of the delicate regulation of protein functions.

关键词： protein phosphorylation bacterium pathogenicity phosphoproteomics

Phylogenetic placement of Cynomorium in Rosales inferred from sequences of the inverted repeat region of the chloroplast genome

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Journal of Systematics and Evolution 2009年第4期47卷 297-304页

作者： ~(1,2)Zhi-Hong ZHANG ~3Chun-Qi LI ~2Jianhua LI~* 1(School of life sciences,sun yat-sen univer.ity,guangzhou 510275,china) 2(Arnold Arboretum of Harvard univer.ity,Cambridge,MA 02138,USA) 3(college of life sciences,Henan Agricultural univer.ity,Zhengzhou 450002,china) (School of life sciences Sun Yat-sen University Guangzhou 510275 China) (Arnold Arboretum of Harvard univer.ity Cambridge MA 02138 USA) (college of life sciences Henan Agricultural University Zhengzhou 450002 China)

Cynomorium is a herbaceous holoparasite that has been placed in Santalales,Saxifragales,Myrtales, or *** inverted repeat(IR)region of the chloroplast genome region is slow evolving and,unlike mitochondrial genes,the chloroplast genome experiences few horizontal gene transfers between the host and parasite. Thus,in the present study,we used sequences of the IR region to test the phylogenetic placements of Cynomorium. Phylogenetic analyses of the chloroplast IR sequences generated largely congruent ordinal relationships with those from previous studies of angiosperm phylogeny based on single or multiple *** was closely related to Caryophyllales and *** formed a clade where Peridiscus was sister to the remainder of the order, whereas Paeonia was sister to the woody clade of *** is not closely related to Santalales, Saxifragales,Myrtales,or Sapindales;instead,it is included in Rosales and sister to *** various placements of the holoparasite on the basis of different regions of the mitochondrial genome may indicate the heterogeneous nature of the genome in the ***,it is unlikely that the placement of Cynomorium in Rosales is the result of chloroplast gene transfer because Cynomorium does not parasitize on rosaceous plants and there is no chloroplast gene transfer between Cynomorium and Nitraria,a confirmed host of Cynomorium and a member of Sapindales.

关键词： Bayesian analyses chloroplast inverted repeat Cynomorium holoparasite maximum likelihood parsimony Rosales.

A provable secure fuzzy identity based signature scheme

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Science china(Information sciences) 2012年第9期55卷 2139-2148页

作者： WANG ChangJi 1,2 1 School of Information Science and Technology,sun yat-sen univer.ity,guangzhou 510275,china 2 Guangdong Province Information Security Key laboratory,sun yat-sen univer.ity,guangzhou 510275,china School of Information Science and Technology Sun Yat-sen University Guangzhou China Guangdong Province Information Security Key laboratory Sun Yat-sen University Guangzhou China

To use biometrics identities in an identity based encryption system,Sahai and Waters first introduced the notion of fuzzy identity based encryption(FIBE) in *** et *** it to digital signature and introduced the concept of fuzzy identity based signature(FIBS) in 2008,and constructed an FIBS scheme based on Sahai and Waters's FIBE *** this paper,we further formalize the notion and security model of FIBS scheme and propose a new construction of FIBS scheme based on bilinear *** proposed scheme not only provides shorter public parameters,private key and signature,but also have useful structures which result in more efficient verification than that of Yang et al.'s FIBS *** proposed FIBS scheme is proved to be existentially unforgeable under a chosen message attack and selective fuzzy identity attack in the random oracle model under the discrete logarithm assumption.

关键词： identity based cryptosystem fuzzy identity based encryption fuzzy identity based signature

Plastid genome sequencing,comparative genomics,and phylogenomics:Current status and prospects

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Journal of Systematics and Evolution 2010年第2期48卷 77-93页

作者： 1Lei GAO 2Ying-Juan SU 1Ting WANG 1(Key laboratory of Plant Germplasm Enhancement and Speciality Agriculture,Wuhan Botanical Garden,Chinese Academy of sciences,Wuhan 430074,china) 2(State Key laboratory of Biocontrol,School of life sciences,sun yat-sen univer.ity,guangzhou 510275,china) (Key laboratory of Plant Germplasm Enhancement and Speciality Agriculture Wuhan Botanical Garden Chinese Academy of Sciences Wuhan 430074 China) (State Key laboratory of Biocontrol School of Life Sciences Sun Yat-sen University Guangzhou 510275 China)

More than 190 plastid genomes have been completely sequenced during the past two decades due to advances in DNA sequencing *** on this unprecedented abundance of data,extensive genomic changes have been revealed in the plastid *** is the most common mechanism that leads to gene order *** inversion events have been recognized as informative phylogenetic markers,such as a 30-kb inversion found in all living vascular plants minus lycopsids and two short inversions putatively shared by all *** loss is a common event throughout plastid genome *** genes were independently lost or transferred to the nuclear genome in multiple plant *** trnR-CCG gene was lost in some clades of lycophytes,ferns,and seed plants,and all the ndh genes were absent in parasitic plants,gnetophytes,Pinaceae,and the Taiwan moth *** parasitic plants have,in particular,lost plastid genes related to photosynthesis because of the relaxation of functional *** dramatic growth of plastid genome sequences has also promoted the use of whole plastid sequences and genomic features to solve phylogenetic *** phylogenomics has provided additional evidence for deep-level phylogenetic relationships as well as increased phylogenetic resolutions at low taxonomic ***,chloroplast phylogenomics is still in its infant stage and rigorous analysis methodology has yet to be developed.

关键词： chloroplast phylogenomics comparative genomics gene loss genome rearrangement plastid genome sequencing

A comparative molecular field analysis of cytotoxic beta-carboline analogs

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Acta Pharmacologica Sinica 2004年第7期25卷 113-119页

作者： Xue-rui HOU, Qi CHEN, Ri-hui CAO, Wen-lie PENG, An-long XU1 Department of Biochemistry and Center for Biopharmaceutical Research, college of life sciences, sun yat-sen univer.ity, guangzhou 510275, china Department of Biochemistry and Center for Biopharmaceutical Research College of Life Sciences Sun Yatsen University Guangzhou 510275

AIM: To derive a model that could be used in drug design. METHODS: Beta-carbolines are reported to have antitumor activities on cultured cancer cell lines. A comparative molecular field analysis (CoMFA) was undertaken to elucidate the correlation of cytotoxities and structural parameters of 16 beta-carboline analogs (1-16). The compound 12 was finally used as a template for the other compounds in the dataset because of its highest biological activity. RESULTS: The CoMFA applied to the final alignment resulted in a qcv of 0.656 and it showed that the 2 steric fields contributed 43.3 % of the model information while the electrostatic fields represented the other 56.7 %. CONCLUSION: Three designed compounds, which were predicted to have high, moderate and low activities respectively, were synthesized. The IC50 values of these compounds indicated the significance of the analysis in this study. The model derived from the current study could be further used in design for more active compounds.

关键词： beta-carbolines quantitative structure-activity relationship alkaloids

Sequences of 72 plastid genes support the early divergence of Cornales in the asterids

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Journal of Systematics and Evolution 2010年第6期48卷 426-434页

作者： 1,2Jianhua LI 3Zhi-Hong ZHANG 1(biology Department,Hope college,Holland,MI 49423,USA) 2(Arnold Arboretum,Harvard univer.ity,Jamaica Plain,MA 02130,USA) 3(School of life sciences,sun yat-sen univer.ity,guangzhou 510275,china) (biology Department Hope College Holland MI 49423 USA) (Arnold Arboretum Harvard University Jamaica Plain MA 02130 USA) (School of life sciences Sun Yat-sen University Guangzhou 510275 China)

Recent phylogenetic analyses of molecular data have supported different hypotheses of relationships among Cornales,Ericales,and core *** hypotheses have implications for the evolution of important morphological and embryological features of *** this study we generated plastid genome-scale data of Davidia(Cornales) and Franklinia(Ericales) and combined them with published sequence data of *** maximum parsimony,maximum likelihood,and Bayesian analyses generated strongly supported and congruent phylogenetic relationships among the three major lineages of the *** diverges first in asterids;Ericales is sister to the core *** two more taxa helps mitigate long branch attraction in parsimony *** 26-28 plastid protein-coding genes may provide satisfactory resolution and support for relationships of eudicots including basal lineages of asterids.

关键词： asterids Cornales Ericales plastid genome scale data.

Studies on rickettsia-like organism (RLO) disease of tropical marine pearl oyster-Epidemiological investigation of RLO disease in juvenile populations of maricultured Pinctada maxima

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Acta Oceanologica Sinica 2003年第3期22卷 421-435页

作者： Xinzhong Wu , Dengfeng Li, Jinpei Pan, Jingbo Jiang college of Animal sciences,Zhejiang univer.ity,Hangzhou 310029,china. Email: wuxz@zju.edu.cnSouth china Sea Institute of Oceanology, Chinese Academy of sciences,guangzhou 510301,chinaSchool of life sciences,sun yat-sen univer.ity,guangzhou 510275,china college of Animal sciences Zhejiang University Hangzhou 310029 China South china Sea Inst. of Oceanology Chinese Academy of Sciences Guangzhou 510301 China School of life sciences SUN YAT-SEN University Guangzhou 510275 China

The death which occurred in juvenile population was a severe problem in the course ofPinctada maxima artificial culture. With the methods of field investigation, histological study and statistic analyses, the epidemiological study was carried out on the disease and death in juvenile populations of Pinctada maxima in the Xinying Pearl Oyster Mariculture Farm of Lingao County (for the A, B and C batches of cultured juveniles hanged in the sea) and the Xincun Pearl Oyster Mariculture Farm of Lingshui County (for the D batch of cultured juvenile hanged in the pond), Hainan Province from November 1993 to April *** results show that the deaths which occurred in juvenile populations of Pinctada maxima presented an outbreak pattern. The peak of mortality rates, in general, occurred in 4-to 6-month old pearl oyster juveniles, and the mortality rates gradully declined with the extention of pearl oyster age after cul-turing 8 months. The correlation between the mortality rates of juvenile populations and mean body lengths of juvenile populations show that the mortality rate become higher under 4 cm of mean body lengths of juvenile population and become obvious declined over 5 cm of mean body lengths. The peak of mortality rate occurred in 1-3 cm of mean body lengths. The results of histological observation showed that rickettsia-like organism inclusions were common, histological widespread infective agent among every batches (A, B, C and D) of cultured juvenile populations. The mean severity indices (SI) of rickettsia-like organism (RLO) infection were positively correlated with mortality rates of juvenile populations. After or within every peaks of RLO infection were all accompanied with the peaks of mortality rates of host populations and the mortality rates declined with decreased RLO infection. So the evidences of histological observation and epidemiology in this study indicated that rickettsia-like organism (RLO) may be as an important pathogenic organism of disease

关键词： Pinctada maxima rickettsia-like organism epidemiology juvenile population

The three-dimensional structure of Infectious flacherie virus capsid determined by cryo-electron microscopy

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Science china(life sciences) 2009年第12期52卷 1186-1191页

作者： XIE Li1,4, ZHANG QinFen2·, LU XingMeng3, DAI XinHong2, LI KunPeng2, HONG Jian1,4· & ZHOU XuePing11 Institute of Biotechnology, Zhejiang univer.ity, Hangzhou 310029, china 2 State Key laboratory of Biocontrol, School of life sciences, sun yat-sen univer.ity, guangzhou 510275, china 3 college of Animal sciences, Zhejiang univer.ity, Hangzhou 310029, china 4 Center of Analysis and Measurement, Zhejiang univer.ity, Hangzhou 310029, china Institute of Biotechnology Zhejiang University Hangzhou China Center of Analysis and Measurement Zhejiang University Hangzhou China State Key laboratory of Biocontrol School of Life Sciences Sun Yat-Sen University Guangzhou China college of Animal sciences Zhejiang University Hangzhou China

Cryo-electron microscopy and image reconstruction were used to determine the three-dimensional structure of Infectious flacherie virus (IFV). 5047 particles were selected for the final reconstruction. The FSC curve showed that the resolution of this capsid structure was 18 ·. The structure is a psuedo T=3 (P=3) icosahedral capsid with a diameter of 302.4 · and a single shell thickness of 15 ·. The density map showed that IFV has a smooth surface without any prominent protrude or depression. Comparison of the IFV structure with those of the insect picorna-like virus-Cricket paralysis virus (CrPV)and human picornavirus-Human rhinovirus 14 (HRV 14) revealed that the IFV structure resembles the CrPV structure. The "Rossmann canyon" is absent in both IFV and CrPV particles. The polypeptide topology of IFV VP2, IFV VP3 was predicted and the subunit location at the capsid surface was further analyzed.

关键词： Infectious flacherie virus cryo-electron microscopy three-dimensional structure polypeptide folding