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Preliminary Mo isotope data of Phanerozoic clastic sediments from the northern margin of the Yangtze block and its implication for paleoenvironmental conditions

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Chinese Science Bulletin 2009年第5期54卷 822-829页

作者： ZHOU Lian GAO Shan CHRIS Hawkesworth corey archer XIE ShuCheng State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Wuhan 430074 China Department of Earth Sciences University of Bristol Bristol BS8 1R J U.K.

Mo isotopes along with Nd isotopes and other geochemical characteristics of the Phanerozoic clastic sediments from the northern margin of the Yangtze block were analyzed by MC-ICP-MS and some other techniques, spanning the period from Cambrian to Jurassic. The δ 98Mo values and εNd(t ) in these sedimets were observed to exhibit a large range of variation (?0.65‰―+1.87‰, ?1.46―?10.90, respec-tively). Specifically, the sample from Late Permian Maokou Formation has relatively positive values in both δ 98Mo and εNd(t ) (+0.97‰, ?1.46, respectively). These elevated values are proposed to relate to the input of a large quantity of H2S and HS- into the contemporaneous seawater by the volcanic eruption of the Emeishan mantle plume. Introduction of these sulfide gases would cause MoO42? to be transferred into MoS24?, favoring the preferential deposition of the heavy Mo isotope as MoS24? and thus leaving a positive Mo isotope value. The sample from Late Permian Changxing Formation has a significantly elevated δ 98Mo value of +1.87‰, in association with the relatively negative εNd(t ) (?10.90) and remain the relatively higher content of both TOC and total sulfur (TS) (1.52%, 2.02%, respectively). This infers the presence of the enhanced primary productivity and high organic burial during the Changxing pe-riod. The production of a huge quantity of HS? and H2S by the sulfate-reducing reaction led to the ex-istence of the elevated seawater δ 98Mo values during the Changxing period. The preliminary Phanero-zoic data reported here allow us to propose that the Mo isotope signature preserved in reductive sediments is related to the regional tectonic settings and the associated environmental conditions, and thus the measurement of δ 98Mo promotes our understanding on the evolution of the paleoenviron-mental event in the Earth history.

关键词：钼同位素古环境显生宙长江

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The oceanic cycles of the transition metals and their isotopes

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Acta Geochimica 2017年第3期36卷 359-362页

作者： Derek Vance corey archer Susan H.Little Michael Kobberich Gregory F.de Souza Department of Earth Sciences Institute of Geochemistry and Petrology ETH Zürich Clansiusstrasse 25 8092 Zürich Switzerland Department of Earth Science and Engineering Imperial College London South Kensington Campus Exhibition Road London SW7 2AZ UK

The stable isotope systems of the transition metals potentially provide constraints on the current and past operation of the biological pump,and on the state of ocean redox in Earth *** we focus on two exemplar metals,nickel(Ni)and zinc(Zn).The oceanic dissolved pool of both elements is isotopically heavier than the known inputs,implying an output with light isotope *** modern oceanic cycle of both these elements is dominated by biological uptake into photosynthesised organic matter and output to *** is increasingly clear,however,that such uptake is associated with only very minor isotope *** suggest that the isotopic balance is instead closed by the sequestration of light isotopes to sulphide in anoxic and organic-rich sediments,so that it is ocean chemistry that controls these isotope systems,and suggesting a different but equally interesting array of questions in Earth history that can be addressed with these systems.

关键词： Ocean biogeochemistry Metal micronutrients Stable isotopes

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扬子克拉通古大陆边缘Mo同位素特征及对有机埋藏量的指示意义

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地球科学（中国地质大学学报） 2007年第6期32卷 759-766页

作者：周炼周红兵李茉王峰 corey archer 中国地质大学地质过程与矿产资源国家重点实验室湖北武汉430074 华中师范大学化学学院湖北武汉430079 Department of Earth Sciences University of Bristol

通过对扬子克拉通古大陆边缘不同时期沉积岩的Mo同位素进行测定,结合Mo微量元素组成,对古大陆边缘Mo的自生作用规律进行了研究,并根据Mo丰度对原始有机碳堆积速率进行了计算.结果表明,其原始有机碳堆积速率在0.17～0.67mmol/m2/day之间... 详细信息

通过对扬子克拉通古大陆边缘不同时期沉积岩的Mo同位素进行测定,结合Mo微量元素组成,对古大陆边缘Mo的自生作用规律进行了研究,并根据Mo丰度对原始有机碳堆积速率进行了计算.结果表明,其原始有机碳堆积速率在0.17～0.67mmol/m2/day之间.利用已建立的现代大陆边缘δ98Mo与有机碳埋藏速率模型,对该区不同时期沉积岩的有机碳埋藏速率进行恢复.结果表明,扬子克拉通显生宙不同时期沉积岩的有机碳埋藏速率有较大的变化范围(0.43～2.87mmol/m2/day),并与原始有机碳堆积速率具有明显的相关性,因此,δ98Mo有可能成为评价有效烃源岩的潜在指标.

关键词： Mo同位素有机碳埋藏速率古大陆边缘

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扬子克拉通北缘显生宙碎屑沉积岩Mo同位素初步研究及其地质意义

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科学通报 2008年第21期53卷 2630-2637页

作者：周炼高山 Chris Hawkesworth corey archer 谢树成中国地质大学地质过程与矿产资源国家重点实验室武汉430074 Department of Earth Sciences University of Bristol Bristol B58 1RJ UK

通过对扬子克拉通北缘西乡-碑坝小区寒武纪-侏罗纪碎屑沉积岩的Mo、Nd同位素进行测定,结合微量元素数据分析,结果表明,该区寒武纪-侏罗纪碎屑沉积岩的δ98Mo变化范围在?0.65‰^+1.87‰之间,εNd(t)变化范围在?1.46~?10.90之间.茅口组晚... 详细信息

通过对扬子克拉通北缘西乡-碑坝小区寒武纪-侏罗纪碎屑沉积岩的Mo、Nd同位素进行测定,结合微量元素数据分析,结果表明,该区寒武纪-侏罗纪碎屑沉积岩的δ98Mo变化范围在?0.65‰^+1.87‰之间,εNd(t)变化范围在?1.46~?10.90之间.茅口组晚期一个样品(4820)具有相对偏正的δ98Mo和εNd(t)(0.97‰,?1.46),有可能与二叠纪晚期峨眉山地幔柱的喷发过程中,扬子克拉通北缘古海水中富集的大量硫化氢有关,此时海水中的MoO42?转变为MoS42?,并具有偏正的Mo同位素组成.晚二叠世长兴期样品(4814)也具有明显偏正的δ98Mo(1.87‰),但εNd(t)相对偏负(?10.90),并具有相对较高的总有机碳(TOC)含量和总硫含量(TS)(分别为1.52%,2.02%),暗示该时期具有较高的初级生产力和有机碳埋藏量,似乎表明脱硫酸还原作用产生的大量HS?,H2S与同期海相沉积岩明显偏正的δ98Mo有一定的耦合性.研究显示,古大陆边缘碎屑沉积岩的Mo同位素变化,与区域构造活动及产生的环境效应存在一定的相关性,可以作为指示区域古环境演化的有效示踪剂.

关键词： Mo同位素碎屑沉积岩古环境事件

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A Review of Hepatitis B Virus and Hepatitis C Virus Immunopathogenesis

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Journal of Clinical and Translational Hepatology 2021年第3期9卷 409-418页

作者： corey Saraceni John Birk University of Connecticut School of Medicine Department of MedicineDivision of Gastroenterology and HepatologyFarmingtonCTUSA

Despite the advances in therapy,hepatitis B virus(HBV)and hepatitis C virus(HCV)still represent a significant global health burden,both as major causes of cirrhosis,hepatocellular carcinoma,and death *** is capable of incorporating its covalently closed circular DNA into the host cell’s hepatocyte genome,making it rather difficult to eradicate its chronic *** viral clearance depends on the complex interactions between the virus and host’s innate and adaptive immune *** encouraging fact on hepatitis B is the development and effective distribution of the HBV *** has significantly reduced the spread of this *** is a RNA virus with high mutagenic capacity,thus enabling it to evade the immune system and have a high rate of chronic *** levels of HCV heterogeneity and its mutagenic capacity have made it difficult to create an effective *** recent advent of direct acting antivirals has ushered in a new era in hepatitis C *** virologic response is achieved with DAAs in 85–99%of ***,this still leads to a large population of treatment failures,so further advances in therapy are still *** article reviews the immunopathogenesis of HBV and HCV,their properties contributing to host immune system avoidance,chronic disease progression,vaccine efficacy and limitations,as well as treatment options and common pitfalls of said therapy.

关键词： Hepatitis B immunopathogenesis Hepatitis C immunopathogenesis

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Little left to lose: deforestation and forest degradation in Australia since European colonization

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Journal of Plant Ecology 2012年第1期5卷 109-120页

作者： corey J.A.Bradshaw The Environment Institute and School of Earth and Environmental Sciences The University of AdelaideAdelaideSouth Australia 5005Australia South Australian Research and Development Institute PO Box 120Henley BeachSouth Australia 5022Australia

Aims Australia is among one of the world’s wealthiest nations;yet,its relatively small human population(22.5 million)has been responsible for extensive deforestation and forest degradation since European settlement in the late 18th *** most(;75%)of Australia’s 7.6 million-km2 area being covered in inhospitable deserts or arid lands generally unsuitable to forest growth,the coastal periphery has witnessed a rapid decline in forest cover and quality,especially over the last 60 *** I document the rates of forest loss and degradation in Australia based on a thorough review of existing literature and unpublished *** Findings Overall,Australia has lost nearly 40%of its forests,but much of the remaining native vegetation is highly *** European colonists expanded in the late 18th and the early 19th centuries,deforestation occurred mainly on the most fertile soils nearest to the *** the 1950s,southwesternWestern Australia was largely cleared for wheat production,subsequently leading to its designation as a Global Biodiversity Hotspot given its high number of endemic plant species and rapid clearing *** the 1970s,the greatest rates of forest clearance have been in southeastern Queensland and northern New SouthWales,although Victoria is the most cleared ***,degradation is occurring in the largely forested tropical north due to rapidly expanding invasive weed species and altered fire *** clear policies to regenerate degraded forests and protect existing tracts at a massive scale,Australia stands to lose a large proportion of its remaining endemic *** most important implications of the degree to which Australian forests have disappeared or been degraded are that management must emphasize the maintenance of existing primary forest patches,as well as focus on the regeneration of matrix areas between fragments to increase native habitat area,connectivity and ecosystem functions.

关键词： biodiversity climate change fragmentation land use restoration

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Cancer cell migration： when red light switched to green

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Asian Journal of Andrology 2011年第2期13卷 177-178页

作者： Seth J corey Jindan Yu Robert H. Lurie Comprehensive Cancer Center Northwestern University Gaiter Pavilion Chicago IL 60611 USA Department of Pediatrics and Department of Cell and Molecular Biology Children＇s Memorial Hospital Northwestern University Medical School Chicago IL 60611 USA Division of Hematology/Oncology Department of Medicine Northwestern University Feinberg School of Medicine Chicago IL 60611 USA

The doctrine of＇the golden mean＇ of the Confucian certainly applies at the molecular level to cell growth and migration. It is critically important for tissue architecture and homeostasis that cells stop prolifera- tion when reaching appropriate density and halt migration in a direction to avoid collision with others. This ＇red light＇ to hinder cell movement is essential for maintaining contact inhibition of locomotion （CIL）--a phe- nomenon that a cell ceases to continue moving in the same direction when it comes into contact with another cell. The concept of CIL emerged initially from the early work of Abercrombie and Heaysman in the 1950s.

关键词： Cells Lymphocytes Lighting Light Migration Cancer (genus) Neoplasms

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Thickness-Dependent Piezoelectric Property from Quasi-Two-Dimensional Zinc Oxide Nanosheets with Unit Cell Resolution

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Research 2021年第1期2021卷 1-7页

作者： corey Carlos Yizhan Wang Jingyu Wang Jun Li Xudong Wang Department of Materials Science and Engineering University of Wisconsin–MadisonMadisonWisconsin 53706USA

A quantitative understanding of the nanoscale piezoelectric property will unlock many application potentials of the electromechanical coupling phenomenon under quantum *** this work,we present an atomic force microscopy-(AFM-)based approach to the quantification of the nanometer-scale piezoelectric property from single-crystalline zinc oxide nanosheets(NSs)with thicknesses ranging from 1 to 4 *** identifying the appropriate driving potential,we minimized the influences from electrostatic interactions and tip-sample coupling,and extrapolated the thickness-dependent piezoelectric coefficient(d_(33)).By averaging the measured d_(33) from NSs with the same number of unit cells in thickness,an intriguing tri-unit-cell relationship was *** NSs with 3n unit cell thickness(n=1,2,3),a bulk-like d_(33) at a value of~9 pm/V was obtained,whereas NSs with other thickness showed a~30%higher d_(33) of~12 pm/*** of d_(33) as a function of ZnO unit cell numbers offers a new experimental discovery toward nanoscale piezoelectricity from nonlayered materials that are piezoelectric in bulk.

关键词： piezoelectric coupling driving

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Environmental impact improvements due to introducing automation into underground copper mines

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International Journal of Mining Science and Technology 2021年第6期31卷 1159-1167页

作者： Kyle Moreau corey Laamanen Ron Bose Helen Shang John Ashley Scott School of Engineering Laurentian UniversitySudburyON P3E 2C6Canada XPS–Glencore Greater SudburyON P0M 1S0Canada

A life-cycle assessment(LCA) model was developed to comparatively analyze the use of manual and automated mining equipment in underground copper mine *** and key variables that were determined to contribute to the environmental impact of operations were identified for six mine sites in a range of geographical locations around the *** model successfully calculated carbon dioxide(CO_(2) eq.) emissions to within 4.9% of the reported annual emissions from the site's respective *** implementation of automation was found to decrease global warming potential by a range of 11.4%-18.0% or 3.9-17.9 kg CO_(2) eq./t *** model was also used to estimate the average reductions across several impact potentials including,acidification(11.9%-17.8%),eutrophication(7.6%-13.7%),and human toxicity(16.0%-20.0%).World-wide the mining industry is moving toward introducing significantly more automation to enhance productivity and *** novel work demonstrates an important third dimension that can support this move,reduced environmental impact.

关键词： Automation Underground copper mines Environmental improvements Life cycle assessment Modelling

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Messages on the Path

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疯狂英语（初中天地） 2008年第10期 66-67页

作者： corey Amaro

There is a message in each step on the path. Gathered in the bold stones and softened by the moss, Rising to meet you in the leaf that sprouts from the crack,

关键词： Messages on the Path

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