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Bulk chemical composition of lherzolitic shergottite Grove Mountains 99027—Constraints on the mantle of Mars

International Conference on Continental Volcanism

作者： Bin He Yi-Gang xu Xiao-Long Huang Zhen-Yu Luo Yu-Ruo Shi Qi-Jun Yang Song-Yue Yu Key Laboratory of Isotope Geochronology and geochemistry guangzhou institute of geochemistry chinese academy of Science guangzhou 510640 china institute of Geology chinese academy of Geological sciences Beijing 100037 china

＜正＞Clastic rocks of the lowermost xuanwei Formation （Group 1）, which directly overlie the Emeishan large igneous province （LIP）, have a geochemical affinity to the Emeishan felsic volcanic rocks, whereas the overlying sediments （Group 2） are compositionally more akin to mafic components of the Emeishan traps. This is the reverse of volcanic sequence of the Emeishan LIP where the felsic extrusives sit above predominantly mafic rocks. It is likely that

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Bulk chemical composition of lherzolitic shergottite Grove M...

Parameter identification theory of a complex model based on global optimization method

中国科学院地质与地球物理研究所2008学术年会

作者： Yangtmg LIN~(1*),Liang QI~2,Guiqm WANG~3,and Lin xu~4 1 Key Laboratory of the Earth’s Deep Interior,institute of Geology and Geophysics,chinese academy of sciences,Beijing 100029,china 2 State Key Lab of Ore Deposit geochemistry,institute of geochemistry,chinese academy of sciences,Guiyang 550002,china 3 guangzhou institute of geochemistry,chinese academy of sciences,guangzhou,china 4 National Astronomic Observatory,chinese academy of sciences,Beijing,china

We report the concentration of 50 elements,including rare earth elements(REEs) and platinum group elements(PGEs) in bulk samples of the Grove Mountains(GRV) 99027 lherzolitic *** abundances of REEs are distinctly lower than those of Allan Hills(ALH) A77005 and other lherzolitic shergottites,indicating that GRV 99027 is not paired with *** may,nevertheless, sample the same igneous unit as the others(Lin et al.2005b;Wang and Chen 2006).The CI-normalized elemental pattern of GRV 99027 reveals low(0.004-0.008×CI) and unfractionated PGEs (except for Pd of 0.018×CI) without depletion of W or Ga relative to lithophile element trends. Fractionation between siderophile and lithophile elements become less pronounced with increase of volatility,except for high abundances of Ni and *** characteristics are probably representative of the mantle of Mars,which is consistent with previous work that the Martian mantle formed in a deep magma ocean followed by a later accretion of chondritic materials.

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Science china(Physics,Mechanics & Astronomy) 2008年第11期51卷 1722-1732页

作者： QU Jie1, JIN QuanLin2 & xu BingYe3 1 College of Automotive Engineering, South china University of Technology, guangzhou 510640, china 2 Beijing Research institute of Mechanical and Electrical Technology, Beijing 100083, china 3 Department of Engineering Mechanics, Tsinghua University, Beijing 100084, china College of Automotive Engineering South China University of Technology Guangzhou China Beijing Research institute of Mechanical and Electrical Technology Beijing China Department of Engineering Mechanics Tsinghua University Beijing China

With the development of computer technology and numerical simulation technology, computer aided engineering (CAE) technology has been widely applied to many fields. One of the main obstacles, which hinder the further application of CAE technology, is how to successfully identify the parameters of the selected model. An elementary framework for parameter identification of a complex model is provided in this paper. The framework includes the construction of objective function, the design of the optimization method and the evaluation of the identified results, etc. The parameter identification process is described in this framework, taking the parameter identification of the superplastic constitutive model considering grain growth for Ti-6Al-4V at 927°C as an example. The objective function is the weighted quadratic sums of the difference between the experimental and computational data for the stress-strain relationship and the grain growth relationship; the designed optimization method is a hybrid global optimization method, which is based on the feature of the objective function and incorporates the strengths of genetic algorithm (GA), the Levenberg-Marquardt algorithm and the augmented Gauss-Newton algorithm. The reliability evaluation of parameter identification result is made through the comparison between the calculated and experimental results and between the theoretical values of the parameters and the identified ones.

关键词： constitutive model parameter identification theory inverse analysis global optimization

维普期刊数据库

Cloning and Identification of Two Novel Splice Variants of Human PD-L2

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 284-289页

作者： Xian-Hui HE#*,Yi LIU&#,Li-Hui xu1, and Yao-Ying ZENG* Key Laboratory of Tissue Transplantation and Immunology, Ji’nan University, Ministry of Education, 601 Huangpu Road West, guangzhou 510632, china 1institute of Bioengineering, Ji’nan University, 601 Huangpu Road West, guangzhou 510632, china Key Laboratory of Tissue Transplantation and Immunology Ji'nan University Ministry of Education601 Huangpu Road West Guangzhou 510632 China institute of Bioengineering Ji'nan University601 Huangpu Road West Guangzhou 510632 China

PD-L2, a newly identified member of B7 family, plays a role in down-regulating T cell responses. The common PD-L2 mRNA (type I) is the splicing product containing all 6 exons. We report here the identification of two human PD-L2 splice variants in activated leukocytes. One splice variant (type II) is generated through splicing out exon 3 encoding Igconstant-like domain; it retains all other regions without a frame shift. The other variant (type III) is created by splicing out exon 3 to an alternative acceptor site 5 bp downstream of the canonical acceptor site, leading to a frame shift. Consequently, the translated protein should be a soluble form. Furthermore, type I isoform is expressed on the plasma surface whereas type II isoform showed a pattern of intracellular membrane distribution in the transiently transfected K562 cells. In addition, the expression patterns of PD-L2 splice variants are variable in different individuals and distinct cellular status. These results suggest that PD-L2 expression may be controlled by posttranscriptional regula- tion through alternative splicing, and modulation of PD-L2 isoform expression may influence the outcome of immune response.

关键词： costimulatory molecules PD-L2 splice variant leukocytes

Comparison of methods for identification of cold tolerance of rice

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chinese Rice Research Newsletter 1991年第3期 3-4页

作者： LIU Yanzhuo CHEN Zhaoming ZHANG xu LIN Daoxuan KONG Qingui Rice Research institute,Guangdong academy of Agricultural sciences,guangzhou 510640,china

Under low temperature stress,theplasmamembrane and chloroplast of plant cellsare impaired,resulting in electrolyte leakage and al-teration of chlorophyll fluorescence which can bemeasured with conductometer and *** cold tolerance of excised leaves of several ricevarieties were determined with these two instru-ments at seedling and heading stages to compare

关键词： Comparison of methods for identification of cold tolerance of rice

Comparison of methods for identification of cold tolerance of rice

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Rice Science 1991年第4期 3-4页

作者： LIU Yanzhuo CHEN Zhaoming ZHANG xu LIN Daoxuan KONG Qingui Rice Research institute,Guangdong academy of Agricultural sciences,guangzhou 510640,china

关键词： Comparison of methods for identification of cold tolerance of rice

Influences of the NAO on the North Atlantic CO2 Fluxes in Winter and Summer on the Interannual Scale

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Advances in Atmospheric sciences 2019年第11期36卷 1288-1298页

作者： Yujie JING Yangchun LI Yongfu xu guangzhou FAN State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China School of Atmospheric sciences Chengdu University of Information Technology Chengdu 610225 China Laboratory for Regional Oceanography and Numerical Modeling Qingdao National Laboratory for Marine Science and Technology Qingdao 266237 China Department of Atmospheric Chemistry and Environmental sciences College of Earth Science University of Chinese Academy of Sciences Beijing 100049 China

The differences in the influences of the North Atlantic Oscillation (NAO) on the air–sea CO2 fluxes (fCO2) in the North Atlantic (NA) between different seasons and between different regions are rarely fully investigated. We used observation-based data of fCO2, surface-ocean CO2 partial pressure (pCO2sea), wind speed and sea surface temperature (SST) to analyze the relationship between the NAO and fCO2 of the subtropical and subpolar NA in winter and summer on the interannual time scale. Based on power spectrum estimation, there are significant interannual signs with a 2–6 year cycle in the NAO indexes and area-averaged fCO2 anomalies in winter and summer from 1980 to 2015. Regression analysis with the 2–6 year filtered data shows that on the interannual scale the response of the fCO2 anomalies to the NAO has an obvious meridional wave-train-like pattern in winter, but a zonal distribution in summer. This seasonal difference is because in winter the fCO2 anomalies are mainly controlled by the NAO-driven wind speed anomalies, which have a meridional distribution pattern, while in summer they are dominated by the NAO-driven SST anomalies, which show distinct zonal difference in the subtropical NA. In addition, in the same season, there are different factors controlling the variation of pCO2sea in different regions. In summer, SST is important to the interannual variation of pCO2sea in the subtropical NA, while some biogeochemical variables probably control the pCO2sea variation in the subpolar NA.

关键词： air-sea CO2 flux North Atlantic Oscillation interannual time scale wind speed surface-ocean CO2 partial pressure

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MIANLUE TECTONIC BELT IN THE SOUTH QINLING MOUNTAINS-REMAINDERS OF AN ANCIENT OCEANIC BASIN

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Scientia Geologica Sinica 1999年第3期 341-347页

作者： Sheng Jihu(Chengdu University of Technoology, Chengdu 610059)Du Yuansheng(china University of Geosciences, Wuhan 430074)xu Jifeng(institute of geochemistry, chinese academy of sciences, guangzhou)Liu Benpei(china University of Geoscioences, Wuhan 430074)

The Mianlue tectonic belt in southem Qinling Moutains is remainders of an anceint oceanic basin. Thisoceanic basin was at least 1000 km wide. It was widely opening during Late Devonian-EarlyCarboniferous. In thia pape... 详细信息

关键词： Zhang MIANLUE TECTONIC BELT IN THE SOUTH QINLING MOUNTAINS-REMAINDERS OF AN ANCIENT OCEANIC BASIN

Volatiles in the mantle transition zone and their effects on big mantle wedge systems

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National Science Review 2024年第6期11卷 15-18页

作者： Yu Wang Yi-Gang xu State Key Laboratory of Isotope geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Southern Marine Science and Engineering Guangdong Laboratory (guangzhou)

The mantle transition zone (MTZ), located between the upper and lower mantle, is characterized by sudden seismicvelocity discontinuities at depths of 410 and 660 km where significant change in mineralogical composition occurs. As a link between the upper and lower mantle,the MTZ is a layer of special significance in Earth’s deep structure, and a critical interface in geodynamics and material circulation.

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Anticancer activity of sodium caffeate and its mechanism

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Acta Pharmacologica Sinica 2005年第10期26卷 1248-1252页

作者： Feng xu~(2,3,4), Sheng-hua ZHANG~3, Rong-guang SHAO~3, Yong-su ZHEN~3 ~2 Department of Pharmacology Zhujiang Hospital, Southern Medical University guangzhou 510280 ~3 Department of Ontology Medicinal Biotechnology, chinese academy of Medical sciences and Peking Union Medical College, Beijing 100050, china Department of Pharmacology Zhujiang Hospital Southern Medical University Guangzhou China Department of Oncology Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences and Peking Union Medical College Beijing China

Aim: To study the anticancer activity of sodium caffeate （SC）. Methods: A nucleoside transport assay was used to analyze the inhibitory effects of SC on nucleoside rescue. The MTT assay was used to measure cell proliferation. Flow cytometrywas used to measure the apoptosis of BEC-7402 induced by SC and the cell cycledistribution change. Western blotting analysis was employed to investigate Bcl2, caspase and Bax expression. Intracellular Ca2+and mitochondrial membranepotential were determined by flow cytometry. In vivo anti-tumor activity wasmeasured using a tumor transplantation model in mice. Results: SC inhibited thenucleoside transport of BEL-7402 cells with an IC50of 1.02 mg/mL. SC inhibitedtumor cell proliferation with an IC50between 100 μg/mL and 200μg/mL. SC induced BEL-7402 cell apoptosis in a time-and dose-dependent manner, which wasinduced by arresting cells in S phase. The in vivo study showed that tumorgrowth was inhibited in a dose-dependent manner. Activated caspase-3 and Baxexpression were up-regulated after treatment with SC, while Bcl-2 expression wasdown-regulated. Intracellular Ca2+was increased while mitochondrial membranepotential was decreased by SC. Conclusion: SC is a new anticancer agent withpromising potential.

关键词： caffeic acid anticancer activity cell division cell apoptosis cell cycle phytogenic antineoplastic agent flow cytometry Western blotting