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Pitfalls in the analysis of ancient human mtDNA

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Chinese Science Bulletin 2003年第8期48卷 826-830页

作者： YAO Yonggang1,3.& ZHANG Yaping1,2.1. Laboratory of Molecular Evolution and Genome Diversity, Kunming institute of Zoology, Chinese {2. of {2., Kunming 6502.3. China 2. Laboratory for Conservation and Utilization of Bio-{3., Yunnan University, Kunming 650091, China 3. Graduate School of the Chinese {2. of {2., beijing 10003., China Correspondence should be addressed to Zhang Yaping (e-mail: zhang- yp1@***) Laboratory of Molecular Evolution and Genome Diversity Kunning Institute of Zoology Chinese Academy of Sciences China Graduate School of the Chinese academy of sciences China Laboratory for Conservation and Utilization of Bio-resource Yunnan University China

The retrieval of DNA from ancient human specimens is not always successful owing to DNA deteriora-tion and contamination although it is vital to provide new insights into the genetic structure of ancient people and to reconstruct the past history. Normally, only short DNA fragments can be retrieved from the ancient specimens. How to identify the authenticity of DNA obtained and to uncover the information it contained are difficult. We employed the ancient mtDNAs reported from Central Asia (including Xin-jiang, China) as an example to discern potentially extraneous DNA contamination based on the updated mtDNA phylog-eny derived from mtDNA control region, coding region, as well as complete sequence information. Our results demon-strated that many mtDNAs reported are more or less prob-lematic. Starting from a reliable mtDNA phylogeney and combining the available modern data into analysis, one can ascertain the authenticity of the ancient DNA, distinguish the potential errors in a data set, and efficiently decipher the meager information it harbored. The reappraisal of the mtDNAs with the age of more than 2.00 years from Central Asia gave support to the suggestion of extensively (pre)historical gene admixture in this region.

关键词：古代人类遗传构造 DNA 脱氧核糖核酸

Underplating in the middle-lower Yangtze Valley and model of geodynamic evolution:Constraints from geophysical data

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Science China Earth sciences 2005年第7期48卷 985-999页

作者： Lü Qingtian, HOU Zengqian, YANG Zhusen & SHI Danian institute of mineral {2.s,Chinese {3. of Geological {4.,beijing 10003.,China institute of mineral {2.s Chinese Academy of Geoloqical Sciences Beijina 100037 China

The lower crust and Moho are the most active boundary layers in the process of continental evolution, in which marks left by tectonic and magmatic activities during the process are preserved. The evolutionary process of the continental lithosphere may be reconstructed by exploring the structures of the lower crust and Moho. According to a study of the deep seismic reflection data obtained from the middle-lower Yangtze Valley, the authors find bright layered reflections ubiquitous in the lower crust and think that the bright reflections are caused by un-derplating of basic or ultrabasic magmas, which might be related to delamination of the lithosphere. On the basis of an integrated analysis of the geophysical and geological data of the region, the authors propose a model for geodynamic evolution of the middle-lower Yangtze Valley. This model suggests that the middle-lower Yangtze Valley had undergone such geodynamic processes as collision-compression, delamination-extension and underplating-melting since the end of the Permian, finally forming the gigantic middle-lower Yangtze Valley metallogenic belt.

关键词： lower crust deep seismic reflection underplating tectonic evolution.

Seasonal patterns of spatial differentiation of landcover change in China

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Chinese Science Bulletin 1999年第4期44卷 362-364页

作者： CHEN YufengState Key Laboratory of resource and Environment Information System , institute of Geography, Chinese {2. of {3., {4. 100101, China State Key Laboratory of resource and Environment Information System Institute of Geography Chinese Academy of Sciences Beijing China

Using the 1°×1° NOAA AVHRR NDVI data set in China, an index on the spatial different gradient of landcover is created. Then based on the index and supported by the geographical information system, it is revealed through principal component and factor analyses methods that there exist four types of seasonal patterns of spatial differentiation of landcover change in China, i.e. November to next March type, June to September type, May or October type and April type.

关键词： landcover spatial differentiation seasonal pattern.

Quartz-Ferberite Oxygen Isotope Geothermometer and Its Geological Applications

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Acta Geologica Sinica(English Edition) 1992年第3期66卷 271-281页

作者： Ding Tiping Liu Yushan Wan Defang Liu Zhijian Li Jincheng Zhang Guilan institute of mineral Deposits, Chinese {2. of Geological {3., {4. institute of mineral Deposits Chinese Academy of Geological Sciences Beijing

Experiments for oxygen isotope exchange between ferberite and water were carried out and the followingequation on oxygen isotope fractionation between ferberite and water against temperature was obtained:Combining this equation with the equation of Clayton et al. (1972. on oxygen isotope fractionation be-tween quartz and water, an equation on oxygen isotope fractionation between quartz and ferberite was ob-tained:The Bigeleison-Mayer function method was used to calculate the oxygen isotope fractionation betweenquartz and ferberite. The theoretical curve obtained agrees with the experimental calibration results quite wellin the temperature range of *** above calibrated equation has been used in 5 world famous tungsten deposits to determine their tem-peratures of formation. The results show that the temperature range for an idividual deposit determined by thisgeothermometer agrees with those obtained from fluid inclusion determination and other isotopegeothermometers.

关键词： geothermometer oxygen isotope quartz--ferberite

A preliminary knowledge-driven prediction model of snail distribution in the Poyang Lake region

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Chinese Science Bulletin 2008年第1期53卷 115-123页

作者： ZHAO An1,2.3.& BAO ShuMing1 1 The Key Lab of Poyang Lake Ecological Environment and resource Development, Jiangxi Normal University, Nanchang 3.002., China 2.institute of Geographic {4. and resources Research, Chinese academy of {4., beijing 100101, China 3.School of Geography and Environmental {4., Jiangxi Normal University, Nanchang 3.002., China The Key Lab of Poyang Lake Ecological Environment and resource Development Jiangxi Normal University Nanchang China institute of Geographic sciences and {2.s Research Chinese Academy of Sciences Beijing China School of Geography and Environmental sciences Jiangxi Normal University Nanchang China

Present monitoring and prediction of schistosomiasis’s intermediate parasite, snail, are based on re-mote sensing image’s spectral signatures, and the calculation result is in fact an incom-plete-constraints solution. TM image of the Poyang Lake region on October 3., 2.05 was combined with GIS thematic data (DEM, boundary of the Poyang Lake, vegetation, soil and land use) to make a prediction on snail spatial distribution in the region by remote sensing, geo-informatics and knowl-edge-driven modeling according to mechanism of snail occurrence. Result shows that with change of overall fuzzy membership of snail occurrence from high to low, snail occurrence of the snail samples of validation group goes up to 81% within 10% high fuzzy membership range, denoting high efficiency of the model in predicting snail occurrence.

关键词：鄱阳湖区域蜗牛分布模糊分类血吸虫病

PGE patterns of ores of Dajing Cu-polymetallic deposit in Linxi County, Inner Mongolia:Indicator to source of metallogenic elements

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Chinese Science Bulletin 2002年第13期47卷 1119-1124页

作者： CHU Xuelei, SUN Min & ZHOU Meifuinstitute of Geology and Geophysics, Chinese academy of {2., {3. 10002., China Key Laboratory of {4. resources, institute of Geology and Geophysics, Chinese academy of {2., {3. 100101, China Department institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Key Laboratory of mineral resources Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Department of Earth sciences The University of Hong Kong Hong Kong China

By comparing PGE patterns of sulfide ores with that of basic-ultrabasic dikes occurring in the Dajing Cu-polymetallic deposit, we discover that there are similar positive slopes between the basic-ultrabasic dikes and the black ores composed mainly of sphalerite and galena, reflecting affinity of their source. The PGE patterns of the yellow ores composed basically of chalcopyrite, arsenopyrite and pyrite are actually different. One is close to the pattern of the mantle 1herzolite, and others resemble the pattern of the basic rocks. However, the concentrations of Ru are higher in the yellow ores, reflecting that sulfur attains or approaches saturation in their parent magma. The PGE characteristics of ores and dikes show that the magmas derived from the deep of crust and the metallogenic elements were supplied mainly by growth material of the crust. In addition, the mantle-derived magma also offered some elements.

关键词： Da Hinggan area polymetallic deposit PGE pattern hypomagma.

^(4.)Ar-^(3.)Ar thermochronology of two ductile shear zones from Yiwulüshan,West Liaoning Region: Age constraints on the Mesozoic tectonic events

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Chinese Science Bulletin 2002年第13期47卷 1113-1118页

作者： ZHANG Xiaohui, LI Tiesheng & PU ZhipingResearch Center of mineral resources Exploration, {2. of Geology and Geophysics, Chinese {3. of {4., beijing 100101, China Guangzhou {2. of Geochemistry, Chinese {3. of {4., Guangzhou 51 Research Center of mineral resources Exploration Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Two ductile shear zones trending EW and NNE respectively not only controlled the tectonic framework of the northern North China, but also constrained the geody-namic background for gold mineralization in this region. Field observations and microstructural analyses reveal that the EW trending ductile shear zones are mainly contributed to dextral compressional deformation resulting from top-to-the-southeast oblique thrust shearing, whereas the NNE trending ones are genetically related to sinistral strike-slip and extensional faulting. One sample from the former yielded an 4.Ar-{2.Ar plateau age of (2.9±4. Ma (Bi) and two samples from the latter gave 4.Ar-{2.Ar plateau ages of (116± 2. Ma (Bi) and (12.±{2. Ma (Bi). These ages provide constraints on the top-to-the-southeast oblique thrusting event occurring in Late Triassic and the sinistral extensional and strike-slip faulting event which occurred in Early Cretaceous.

关键词： 4.Ar-3.Ar age biotite ductile shear zone West Liaoning Region.

Electron Microscopic Study of Manganese minerals in the Polymetallic Nodules from the Central Pacific Ocean

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Acta Geologica Sinica(English Edition) 1993年第1期67卷 33-41,123-124页

作者： Xiao Xuqi institute of mineral Deposits, Chinese {2. of Geological {3., {4. Guo Shiqin China Ocean mineral Researches and Development Association (COMRA), {4. Jiang Minxi institute of mineral Deposits Chinese Academy of Geological Sciences Beijing China

Manganese minerals in the polymetallic nodules from the Central Pacific Ocean were studied using electron microscopy. The principal Mn minerals, being vernadite and todorokite, exhibit different electron diffraction patterns and morphological features. According to its morphological feature, todorokite shows three phases: fibrous, lamellar and lath-shaped. Both vernadite and todorokite are authigenic minerals. While vernadite was mainly precipitated directly from the relevant solution by microbiological oxidation, todorokite was separated from the solution chemically without the help of microbe. Hence, these two minerals show a close genetic relation.

关键词： electron microscope polymetallic nodules vernadite todorokite

Application of the phylogenetic analysis in mitochondrial disease study

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Chinese Science Bulletin 2008年第18期53卷 2733-2738页

作者： WANG ChengYe1,2.3. KONG QingPeng1,2.& ZHANG YaPing1,2. 1 State Key Laboratory of Genetic resources and Evolution, Kunming {2. of Zoology, Chinese {2. of {3., Kunming 6502.3. China 2.Laboratory for Conservation and Utilization of Bio-resource, Yunnan University, Kunming 650091, China 3.Graduate University of Chinese {2. of {3., beijing 10004., China Chinese Acad Sci Kunming Inst Zool State Key Lab Genet Resources and Evolut Kunming 650223 Peoples R China.

Mitochondrial disease currently received an increasing concern. However, the case-control design commonly adopted in this field is vulnerable to genetic background, population stratification and poor data quality. Although the phylogenetic analysis could help solve part of these problems, it has not received adequate attention. This paper is a review of this method as well as its application in mito- chondrial disease study.

关键词：线粒体疾病分析单元型种群分布