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Age of Yingfeng rapakivi granite pluton on the north flank of Qaidam and its geological significance

Science China Earth Sciences 2004年第4期47卷 357-365页

作者： XIAO Qinghui1,2, LU Xinxiang1,3. WANG Fei4. SUN Yangui5, WEI Xiangdong3.& XING Zuoyun6 1. Division of Granite Geology, China Geological Survey, Yichang 4.3.03. China 2. Information Center of Ministry of Land and Resources, {4. 100812, China 3. Geological Survey of Henan Province and Institute of Geological Research of Henan Province, Zhengzhou 4.0053. China 4. Geological Institute, China Seismological Bureau, {4. 100029, China 5. Geological Survey Institute of Qinghai Province, Xining 81003., China 6. China university of {3., Wuhan 4.0}074. China Division of Granite Geology China Geological Survey Yichang China Information Center of Ministry of Land and Resources Beijing China Geological Survey of Henan Province and Institute of Geological Research of Henan Province Zhengzhou China Geological Institute China Seismological Bureau Beijing China Geological Survey Institute of Qinghai Province Xining China China university of geosciences Wuhan China

The Yingfeng rapakivi granite on the north flank of Qaidam is a newly discovered Proterozoic rapakivi pluton in China, which was found after the discovery of Shachang rapakivi in Miyun County, beijing and Kuandian rapakivi in Jilin Province. Yingfeng rapakivi pluton is ex-posed on the north side of the suture belt between Qinling-Kunlun orogenic belt and North China plate. U-Pb zircon isotopic dating and Ar-Ar isotopic dating of both hornblende and K-feldspar from the Yingfeng rapakivi granite have been conducted. The results show that the age of (1776±3.)Ma at the upper intercept in Concorde diagram represents the age of formation of the plu-ton, whereas the age of (526 281) Ma at the lower intercept and Ar-Ar mineral dating of horn-blende and K-feldspar correspond to the age of a later event affecting the pluton, suggesting that Yingfeng pluton has ever been affected by strong regional Caledonian-Hercynian tectonic movement after its formation. The discovery of middle Proterozoic Yingfeng rapakivi granite pro-vides a petrologic evidence for the timing of cratonization of both the continental crust basement in western China and the basement of the North China plate and for a rifting event taking place in the mid-Proterozoic, suggesting that an amalgamation of ancient China continents had ever happened during the L liang Movement?between the early Proterozoic and the mid-Proterozoic.

关键词： rapakivi, U-Pb dating, Ar-Ar dating, Kunlun-Qinling orogenic belt.

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In situ reproductive organs of Early Cretaceous ferns from Northeast China

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Chinese Science Bulletin 1997年第23期42卷 1977-1980,2026页

作者： DENG Shenghui and CHEN Fen1. Research Institute of Petroleum and Development, beijing 100083.2. China university of {3., beijing 100083. China Research Institute of Petroleum and Development Beijing China university of geosciences Beijing China

FILICOPSIDA is a predominant group of the Early Cretaceous floras of Northeast China, whichapproximates 100 species and accounts for more than one third of the floras. The majority ofthis group are of great importance and significance in stratigraphy. The previous studies ofthese ferns are mainly morphological, with only a few concerning the in situ spores andsporangia. In recent years. the authors have carried out a research project on the in situreproductive organs of the Early Cretaceous ferns from/ basins of Inner Mongolia, Liaoning,Jilin and Heilongjiang of Northeast China. The study focuses on 3. species of 17 genera be-longing to 10 families. The present note briefly introduces the results of this study by listingsome representative species.

关键词： Northeast China Early Cretaceous Filicopsida in situ reproductive organs.

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Re-Os age for molybdenite from the Gangdese porphyry copper belt on Tibetan plateau: Implication for geody- namic setting and duration of the Cu mineralization

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Science China Earth Sciences 2004年第3期47卷 221-231页

作者： HOU Zengqian1, QU Xiaoming1, WANG Shuxian2, DU Andao2, GAO Yongfeng3.& HUANG Wei4.1. Institute of Mineral Resources, Chinese Academy of Geological Sciences, beijing 10003., China 2. National Center of Geoanalysis, Chinese Academy of Geological Sciences, beijing 10003., China 3. Shijiazhuang College of Economy, Shijiazhuang 056000, China 4. Xizang Bureau of Geology and Mineral Resources, Lhasa 850000, China Institute of Mineral Resources Chinese Academy of Geological Sci. Beijing 100037 China National Center of Geoanalysis Chinese Academy of Geological Sci. Beijing 100037 China Shijiazhuang College of Economy Shijiazhuang 056000 China Xizang Bureau of Geol./Mineral Rsrc. Lhasa 850000 China

The Gangdese porphyry copper belt consists of one large and five middle-small deposits in addition to dozens of ore-bearing porphyry bodies. The belt trends 3.0 km long along the EW-striking Gangdese batholith, and locally occurs as a string of beads extending about 50 km within the SN-trending rifting zones (grabens) on the Tibetan plateau. Monzonitic granite- porphyry and quartz monzonitic porphyry, as dominant host rocks, are shoshonitic and potassic calc-alkaline. Available dating data indicate that the ages of the shallow-level emplacement for these porphyries vary from 10 Ma to 18 Ma, which are identical to that of associated potassic calc-alkaline volcanic rocks (10—15 Ma) and mafic dykes (13.18 Ma). The timing and duration of Cu mineralization events are constrained by Re-Os ages for molybdenites from three porphyry copper deposits in the Gangdese porphyry copper belt. Five molybdenite samples from the Nanmu deposit yielded an 187Re-187Os isochron with a highly pre-cise age of (14.76?.22) Ma; six molybdenites from the Chongjiang deposit gave an isochron age of (14.04..16) Ma. Re-Os model ages for two molybdenite samples from Lakang抏 deposit vary from 13.5 Ma to 13.6 Ma, which are basically identical to isochron ages mentioned above. All the thirteen samples from these three deposits yielded a linear array in the isochron diagram with a higher correlation coefficient of 0.99719 and an isochron age of (14.3.?.22) Ma (1s error), suggesting an coeval event of the Cu mineralization and a shared source of ore materials for the Gangdese porphyry copper belt. Compared with the longer-lived felsic magmatic-hydrothermal system, the Cu mineralization is a relatively short event with duration of about 0.5 Ma, and usu-ally occurs in the later-stage of the complicate magmatic system. The emplacement age of the Gangdese porphyries indicates that they intruded after the rapid rising of the Gangdese Mountains at 21—23.Ma, and formed in a post-collision crustal ex-tension env

关键词： porphyry copper deposit, Re-Os age, Gangdese, Tibetan plateau.

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South China's Gondwana connection in the Paleozoic:Paleomagnetic evidence

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Progress in Natural Science:Materials International 2004年第1期14卷 86-91页

作者： ZHANG Shihong*(School of Earth Sciences and Resources, China university of geosciences, beijing {3. China) China Univ Geosci Sch Earth Sci & Resources Beijing 100083 Peoples R China

The reconstruction in which the South China Block (SCB) lies along the Great India Australia region of Gondwana margin is tested by using existing Paleozoic paleomagnetic data. Under the proposed reconstruction, all six high quality paleopoles from the SCB between the Early Cambrian and late Early Devonian (～4.0 Ma) are in good agreement with coeval paleopoles from Gondwana. Thereafter, the apparent polar wander paths for the SCB and Gondwana diverge markedly. This indicates that the SCB had been part of Gondwana and the connection was intact from at least Early Cambrian until late Early Devonian, but they began to separate by late Middle Devonian (～3.5 Ma).

关键词： South China block Gondwana paleomagnetism reconstruction

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Paleotemperature changes over the past 3.00 years in eastern beijing, China: A reconstraction based on Mg/Sr records in a stalagmite

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Chinese Science Bulletin 2003年第4期48卷 395-400页

作者： MA Zhibang1, LI Hongchun2, XIA Ming1, KU Tehlung2, PENG Zicheng3. CHEN Yushu4.& ZHANG Zhaofeng3.1. Institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029, China 2. Department of Earth Sciences, university of Southern California, Los Angeles, CA90089-074., USA 3. Department of Earth and Space Science, university of Science and Technology of China, Hefei 23.026, China 4. beijing Foshan Tourist Service Centre, beijing 101201, China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing 100029 China Department of Earth Sciences University of Southern California Los Angeles CA 90089-0740 United States Department of Earth and Space Science University of Science and Technology of China Hefei 230026 China beijing Foshan Tourist Service Centre Beijing 101201 China

The Mg/Sr ratio in a stalagmite, which is di-rectly proportional to DMg/Ca, the solid-liquid distribution coefficient of Mg, is proposed as a geochemical thermometer to estimate paleotemperature changes. The paleotempera-ture change in eastern beijing over the past 3.00 years has been reconstructed by using this thermometer in the stalag-mite ZFFS-1 from Jingdong Cave. The records can be di-vided into two periods: 3.00—2000 aBP, cool and wet, the air temperature averaging 9.8℃; and 2000 aBP—present, hot and dry, the air temperature being 1℃ higher than the mean value (11.7℃) of the past 3.00 years. During 500—200 aBP, the air temperature was about 1.2℃ lower than that of the present, corresponding to the Little Ice Age in Europe. Like d 18O and d 13., Mg/Sr (or DMg/Ca) reflects an obviously warming trend of the past 200 years. These results are sup-ported by historic records.

关键词：北京京东溶洞石笋 Mg/Sr记录古气温测年 3.00年

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Isotopic feature and uranium dating of the volcanic rocks in the Okinawa Trough

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中国科学：地球科学英文版 2006年第4期49卷 375-383页

Volcanic rocks from the northern and middle Okinawa Trough were dated by ura- nium-series dating method. Differential fractions using magnetic procedure were designed to separate samples. New report on the ages and isotopic data of rocks in the northern trough (especially black pumice) was discussed. Based on the uranium dates and Sr-Nd isotopic ratio, magmatic evolution process of the Okinawa Trough was noted. Firstly, there have been wide silicic volcanic activities in the Okinawa Trough from late Pleistocene to present, and the volcanic rocks can be divided into three subgroups. Secondly, magma generally came from PREMA source area under the Okinawa Trough. Magmatic evolution in the northern trough was similar to the middle, but different to the south. Finally, volcanic activities indicated that opening of the southern Okinawa Trough did not happen due to the collision between Luson Arc and Eurasian Plate until the early Pleistocene.

关键词： Okinawa Trough, black pumice, uranium-series dating, Sr-Nd isotopic ratio, magmatic evolution.

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Mining and Integrating Reliable Decision Rules for Imbalanced Cancer Gene Expression Data Sets

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Tsinghua Science and Technology 2012年第6期17卷 666-673页

作者： Hualong Yu 1 , Jun Ni 2 , Yuanyuan Dan 3., Sen Xu 4.1. School of Computer Science and Engineering, Jiangsu university of Science and Technology, Zhenjiang 212003. China 2. Department of Radiology, Carver College of Medicine, The university of Iowa, Iowa City, IA 5224., USA 3. School of Biology and Chemical Engineering, Jiangsu university of Science and Technology, Zhenjiang 212003. China 4. School of Information Engineering, Yancheng Institute of Technology, Yancheng 224.51, China School of Computer Science and Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China Department of Radiology Carver College of Medicine The University of Iowa Iowa City IA 52242 USA School of Biology and Chemical Engineering Jiangsu University of Science and Technology Zhenjiang 212003 China School of Information Engineering Yancheng Institute of Technology Yancheng 224051 China

There have been many skewed cancer gene expression datasets in the post-genomic era. Extraction of differential expression genes or construction of decision rules using these skewed datasets by traditional algorithms will seriously underestimate the performance of the minority class, leading to inaccurate diagnosis in clinical trails. This paper presents a skewed gene selection algorithm that introduces a weighted metric into the gene selection procedure. The extracted genes are paired as decision rules to distinguish both classes, with these decision rules then integrated into an ensemble learning framework by majority voting to recognize test examples; thus avoiding tedious data normalization and classifier construction. The mining and integrating of a few reliable decision rules gave higher or at least comparable classification performance than many traditional class imbalance learning algorithms on four benchmark imbalanced cancer gene expression datasets.

关键词： cancer gene expression data class imbalance paired differential expression genes decision ruleensemble learning majority voting

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Sodium hydrosulfide alleviated pulmonary vascular structural remodeling induced by high pulmonary blood flow in rats

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Acta Pharmacologica Sinica 2006年第8期27卷 971-980页

作者： Xiao-hui LI~2 Jun-bao DU~(2,6) Ding-fang BU~3.Xiu-ying TANG~4.Chao-shu TANG~5 ~1Department of Pediatrics,Peking university First Hospital,Key Laboratory of Molecular Cardiovascular Diseases,Ministry of Education ~3.Laboratory Center ~4.aboratory of Electron Microscopy,Peking university First Hospital,{4. 10003.,China ~5Department of Physiology,Peking university Health Science Center,{4. 100083.China Department of Pediatrics Peking University First Hospital Key Laboratory of Molecular Cardiovascular Diseases Ministry of Education Beijing China Laboratory Center Peking University First Hospital Beijing China Laboratory of Electron Microscopy Peking University First Hospital Beijing China Department of Physiology Peking University Health Science Center Beijing China

Aim:To explore the possible role of endogenous hydrogen sulfide （H2S）,a novelgasotransmitter,in the pathogenesis of pulmonary vascular structural remodeling（PVSR） induced by high pulmonary blood ***:Thirty-two Sprague-Dawley male rats were randomly divided into sham,shunt,sham+NaHS （a H2Sdonor） and shunt+NaHS *** in shunt and shunt+NaHS groups under-went an abdominal aorta-inferior vena cava shunt,and rats in shunt+NaHS andsham+NaHS groups were intraperitoneally injected with *** was inves-tigated using optical microscope and transmission electron *** H2S was evaluated by sulfide-sensitive *** oxide synthase（NOS）,heme oxygenase （HO-1）,proliferative cell nuclear antigen （PCNA） andextracellular signal-regulated kinase （ERK） activation were analyzed by ***:After 11 weeks of shunting,PVSR developed with a decrease inlung tissue H2S production and an increase in nitric oxide （NO）.However,lungtissue carbon monoxide （CO） did not *** the treatment with NaHS for11 weeks,H2S donor ameliorated PVSR and downregulated PCNA expression andERK activation with an increase in lung tissue CO production and HO-1 proteinexpression but a decrease in NO production,NOS activity and eNOS proteinexpression in shunted ***:H2S exerted a regulatory effect on PVSRinduced by high pulmonary blood ***,H2S down-regulated theERK/MAPK signal pathway,inhibited the NO/NOS pathway and enhanced theCO/HO pathway in rats with high pulmonary blood flow.

关键词： hydrogen sulfide pulmonary hypertension structure remodeling nitric oxide/nitric oxide synthase carbon monoxide/heme oxygenase

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Alterations in DNA methylation and genome structure in two rice mutant lines induced by high pressure

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Science China(Life Sciences) 2006年第2期49卷 97-104页

作者： SHEN Sile1,3. WANG Zhenwei3. SHAN Xiaohui2, WANG Hua3. LI Ling3. LIN Xuyun2, LONG Likun2, WENG Kenan4. LIU Bao2 & ZOU Guangtian1 1. National Laboratory of Superhard Materials, Jilin {4., Changchun 13.012, China 2. Institute of Genetics and Cytology, Northeast Normal {4., Changchun 13.024. China 3. College of Life Science, Jilin {4., Changchun 13.012, China 4. Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51064., China National Laboratory of Superhard Materials Jilin University Changchun China College of Life Science Jilin University Changchun China Institute of Genetics and Cytology Northeast Normal University Changchun China Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

By using high-pressure treatment, two mutant lines were obtained from agenetically stable japonica rice cultivar Bijing3.. Genomic DNA of the mutant lines, together withthe original line (Bijing3.), was either undigested or digested by Hpa ⅡIMspⅠ, and then subjectedto molecular analysis using two markers, ISSR and RAPD. Results indicated that changes in the PCRamplification profiles of both markers are apparent in the two mutant lines compared with theoriginal rice cultivar, suggesting that there had been both sequence changes and DNA methylationmodifications in the mutant lines. Southern blot analysis using diverse sequences, including twocellular genes (S2 and S3., a set of retrotransposons (Osr7, Osr3., Tos19 and more), and a MITEtransposon family (mPing and Pong), confirmed the results, and indicated that changes in DNAmethylation pattern, genomic structure, and possible activation of some transposons indeed occurredin the mutant lines. Moreover, these changes are stably maintained through selfed generations and indifferent organs. Thus, our results indicate that it is possible to obtain stable mutants in riceby high pressure treatments, and the molecular basis of the mutants may include both genetic andepigenetic changes. Therefore, high hydrostatic pressure seems a promising approach for plantmutagenesis.

关键词： DNA methylation, genomic changes, high pressure, mutagenesis, rice.

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Structure Relaxation of Mg_(65)Cu_(25)Gd_(10) Metallic Glass and Its Effect on Strength

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Journal of Wuhan university of Technology(Materials Science) 2009年第2期24卷 210-213页

作者：李国强 School of Materials Science & Engineering Beijing University of Aeronautics and Astronautics China Perfect Machinery Industry Corp. Ltd

To identify the re-arrangement of constituent atoms of an amorphous Mg65Cu25Gd10 alloy happened with annealing, structure relaxation of the alloy was investigated as a function of an- nealing time at 3.3.K through extended X-ray absorption fine structure （EXAFS） analysis procedures. To understand the effect of structure relaxation on strength, compression tests were conducted for both the as-cast and the annealed Mg65Cu25Gd10 samples. It is found that short range order around Cu and Gd atoms exhibits different variation trends with increasing annealing time at 3.3.K, though the structure of the alloy still remains to be amorphous. Based on the fact that the strength of the alloy first exhibits a reduction and then a recovery with annealing time, it is suggested that the enhancement of short range order around Cu should be responsible for the strength reduction, while the enhancement of short range order around Gd should be responsible for the strength recovery.

关键词： Mg-based metallic glass structure relaxation strength annealing

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