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奥陶系上统赫南特阶全球层型剖面和点位的建立

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地层学杂志 2006年第4期30卷 289-305,T0001-T0002页

作者：陈旭戎嘉余樊隽轩詹仁斌 C.E.Mitchell d.a.t.harper M.J.Melchin 彭平安 S.C.Finney 汪啸风现代古生物学和地层学国家重点实验室中国科学院南京地质古生物研究所江苏南京210008 纽约州立大学地质系美国纽约ny142603050 哥本哈根大学地质博物馆圣弗朗西斯萨维尔大学地球科学系有机地球化学国家重点实验室中国科学院广州地球化学研究所广东广州510000 加州州立大学地球科学系美国长滩ca90840 国土资源部宜昌地质矿产研究所湖北宜昌443003

赫南特阶(上奥陶统)的全球界线层型剖面和点位确立在中国宜昌王家湾北剖面观音桥层底界之下0.39m处。该剖面位于中国湖北省宜昌市以北42km处的王家湾村,经纬度为30°58′56″N、111°25′10″E。赫南特阶底界的GSSP点位以笔石Normalogra... 详细信息

赫南特阶(上奥陶统)的全球界线层型剖面和点位确立在中国宜昌王家湾北剖面观音桥层底界之下0.39m处。该剖面位于中国湖北省宜昌市以北42km处的王家湾村,经纬度为30°58′56″N、111°25′10″E。赫南特阶底界的GSSP点位以笔石Normalograptusextraordinarius的首次出现层位(FAd)为标志。碳同位素在此层位显示的正漂移以及***的首现可作为第二标志。赫南特阶始于自diceratograptusmirus亚带开始的全球生物大灭绝事件的主幕之后。王家湾北剖面出露完整,沉积和生物序列连续,笔石和壳相动物化石丰富并保存良好,王家湾北、王家湾南和王家湾小河边剖面都发育了合适的沉积相和生物相并具有广泛对比的潜力。该地区地质构造简单,岩石未经历较强的变质作用,且交通便利。王家湾小河边剖面尤其适合进行化学地层学研究和同位素年龄的测定。建立赫南特阶底界的全球界线层型剖面和点位的提案报告于2004年10月被国际地层委员会奥陶系分会通过,经补充完善后,于2006年2月被国际地层委员会通过,同年5月被国际地科联正式批准。

关键词：奥陶系赫南特阶全球界线层型剖面和点位(GSSP)

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扬子区奥陶纪末赫南特亚阶的生物地层学研究

地层学杂志 2000年第3期24卷 169-175,200页

作者：陈旭戎嘉余樊隽轩詹仁斌张元动王志浩王宗哲李荣玉王怿米切尔(C.E.Mitchell) 哈帕尔(d.a.t.harper) 中国科学院南京地质古生物研究所江苏南京210008 美国纽约州立大学地质系布法罗ny142603050 丹麦哥本哈根大学地质博物馆

重新研究了宜昌王家湾 ,宜昌分乡 ,桐梓红花园和松桃陆地坪 4条上奥陶统上部至志留系底部的连续采集剖面。1999年 6月在捷克召开的第 8届国际奥陶系大会上提名宜昌王家湾和桐梓红花园剖面分别为赫南特亚阶的全球层型候选剖面 (GSSP)和... 详细信息

重新研究了宜昌王家湾 ,宜昌分乡 ,桐梓红花园和松桃陆地坪 4条上奥陶统上部至志留系底部的连续采集剖面。1999年 6月在捷克召开的第 8届国际奥陶系大会上提名宜昌王家湾和桐梓红花园剖面分别为赫南特亚阶的全球层型候选剖面 (GSSP)和辅助剖面。对赫南特亚阶及其上、下地层的生物带重新厘定 ,自下而上为 Foliomena-N ankinolithus/***,***带 ,***带 (包括下部亚带 ,***亚带和 diceratograp-tus mirus亚带 ) ,***- ***带 ,***带 ,***带和 ***带。

关键词：赫南特亚阶奥陶系扬子区生物地层学

Late Ordovician Mass Extinction: Earth, fire and ice

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National Science Review 2024年第1期11卷 51-65页

作者： david.a.t.harper Palaeoecosystems Group Department of Earth SciencesDurham University

the Late Ordovician Mass Extinction was the earliest of the ‘big’ five extinction events and the earliest to affect the trajectory of metazoan life. two phases have been identified near the start of the Hirnantian period and in the middle. It was a massive taxonomic extinction, a weak phylogenetic extinction and a relatively benign ecological extinction. A rapid cooling, triggering a major ice age that reduced the temperature of surface waters, prompted a drop in sea level of some 100 m and introduced toxic bottom waters onto the shelves. these symptoms of more fundamental planetary processes have been associated with a range of factors with an underlying driver identified as volcanicity. Volcanic eruptions, and other products, may have extended back in time to at least the Sandbian and early Katian, suggesting the extinctions were more protracted and influential than hitherto documented.

关键词： Ordovician LOME paleoecology palaeobiogeography biotas

the Golden Spike Still Glitters:the(Re)construction of a Global Chronostratigraphy

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同方期刊数据库

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Acta Geologica Sinica(English Edition) 2019年第S01期93卷 24-27页

作者： david.a.t.harper Palaeoecosystems Group Department of Earth SciencesDurham UniversityDurham DH13LEUK

1 Introduction Stratigraphy,placing the sequence of events in Earth history into order,is a fundamental part of the *** the starting point is a regional stratigraphy,based on lithological,mappable units,correlated by fossils with local,regional and global chronostratigraphical *** units were traditionally defined on their fossil content,as essentially unit ***,commonly there were no clear boundaries.

关键词： stratigraphy biostratigraphy GSSPs milankovitch cycles timescale

Controlling human platelet activation with calcium-binding nanoparticles

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Nano Research 2020年第10期13卷 2697-2705页

作者： david Cabrera Karen Walker Sandhya Moise Neil d.telling Alan G.S.harper School of Pharmacy and Bioengineering Keele UniversityGuy Hilton Research CenireThormburrow DriveHartshill Stoke-on Trent ST47QBUK ?Central Electron Microscope Unit School of Life SciencesKeele UniversityNewcastle-under LIymeStaffordshireST55BGUK department of Chemical Engineering University of BathBath BA27AYUK School of Medicine Keele UniversityNewcastle-under-LymeStaffordshireST55BGUK

Human platelets aggregate at sites of blood vessel damage in response to a rise in their cytosolic calcium *** these cytosolic calcium rises would provide a method to inhibit platelet activation and prevent the unwanted blood clots that causes heart attack and *** we have predicted that calcium accumulation within the lumen of an infolded portion of the platelet plasma membrane called the open canalicular system(OCS)is essential for maintaining this cytosolic calcium *** to its nanometer dimensions of the OCS,it has been difficult to measure or interfere with the predicted luminal calcium *** we utilise iron oxide magnetic nanoparticles coated with the known calcium chelator,citrate,to create calcium-binding *** were used to assess whether an OCS calcium store plays a role in controlling the dynamics of human platelet activation and *** demonstrate that citrate-coated nanoparticles are rapidly and selectively uptaken into the OCS of activated human platelets,where they act to buffer the accumulation of calcium *** with these calcium-binding nanoparticles reduced thrombin-evoked cytosolic calcium rises,and slowed platelet aggregation and clot retraction in human *** contrast,nanoparticles that cannot bind calcium have no *** study demonstrates that the OCS acts as a key source of calcium for maintaining cytosolic calcium rises and accelerating platelet aggregation,and that calcium-binding nanoparticles targeted to the OCS could provide an anti-platelet therapy to treat patients at risk of suffering heart attacks or strokes.

关键词： nanochelators human platelets open canalicular system calcium signaling nanoparticles

Recent Advances in the Science of Burst Wave Lithotripsy and Ultrasonic Propulsion

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Biomedical Engineering Frontiers 2022年第1期3卷 48-53页

作者： dima Raskolnikov Michael R.Bailey Jonathan d.harper department of Urology University of Washington School of MedicineSeattleWAUSA Center for Industrial and Medical Ultrasound Applied Physics LaboratoryUniversity of WashingtonSeattleWAUSA

Nephrolithiasis is a common,painful condition that requires surgery in many patients whose stones do not pass *** technologic advances have enabled the use of ultrasonic propulsion to reposition stones within the urinary tract,either to relieve symptoms or facilitate *** wave lithotripsy(BWL)has emerged as a noninvasive technique to fragment stones in awake patients without significant pain or renal *** review the preclinical and human studies that have explored the use of these two *** envision that BWL will fill an unmet need for the noninvasive treatment of patients with nephrolithiasis.

关键词： urinary surgery advances

Contact patterning by laser printing for flexible electronics on paper

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npj Flexible Electronics 2019年第1期3卷 94-99页

作者： Angela F.harper Peter J.diemer Oana d.Jurchescu department of Physics and Center for Functional Materials Wake Forest UniversityWinston-SalemNC 27109USA Cavendish Laboratory Department of PhysicsUniversity of CambridgeJ.J.Thomson AvenueCambridge CB30HEUK

the desire for cost-effective strategies for producing organic electronic devices has led to many new methods for the organic semiconductor layer deposition;however,manufacturing contacts remains an expensive technique due to the high cost of both the materials used and the processing necessary for their *** this work,we present a method for contact deposition and patterning,which overcomes these limitations and allows fabrication of all-printed organic thin-film transistors on *** method relies on depositing contacts using aerosol spray and patterning them with a digitally printed mask from an office laser printer,at ambient temperature and *** technique,which we have denoted aerosol spray laser lithography,is costeffective and extremely versatile in terms of material choice and electrode *** the processing temperature does not exceed 155℃,it is compatible with a variety of substrates,including plastic or *** success of this method marks an opportunity for a rapid,scalable,and low-cost alternative to current electrode-manufacturing techniques for development of flexible,large-area,electronic applications.

关键词： cost electrode printing

华东志留纪最早期的华夏正形贝动物群及其宏演化意义

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古生物学报 2008年第2期47卷 141-167页

作者：戎嘉余黄冰詹仁斌 d.a.t.harper 现代古生物学和地层学国家重点实验室中国科学院南京地质古生物研究所南京210008 Geological Museum University of Copenhagen Фster Voldgade 5-7 DK-1350 Copenhagen Denmark

志留纪最早期的腕足动物群在文献中很少记录,与标准笔石相伴者更为稀罕。江西玉山志留系底部因发现Akidograptus ascensus带的笔石而确定该处盛产志留纪初期(鲁丹早期)、多样性较高的腕足动物群。根据组成、性质与层位,它与浙江江山、... 详细信息

志留纪最早期的腕足动物群在文献中很少记录,与标准笔石相伴者更为稀罕。江西玉山志留系底部因发现Akidograptus ascensus带的笔石而确定该处盛产志留纪初期(鲁丹早期)、多样性较高的腕足动物群。根据组成、性质与层位,它与浙江江山、常山、淳安、余杭等7个地点的同期组合可统一命名为华夏正形贝动物群(Cathay-siorthis Fauna)。它包含了不同群集,都产自细碎屑岩(如泥岩)中,其分布主要受海水深度和距华夏古陆远近的控制。这个动物群生长在奥陶纪大灭绝后的残存期,文章探讨了它的残存特征。研究揭示,奥陶纪末大灭绝对腕足动物演化的一个实质性的贡献在于制约了奥陶纪占优势的A组(正形贝/扭月贝大类群:发育铰合面、窗齿型铰齿、正扭型主突起和简单腕器官)的繁盛态势,滋生了B组(五房贝/无洞贝大类群:发育后转面、弓齿型铰齿和复杂腕器官但缺失正扭型主突起)在志留纪的优势,造成腕足动物宏演化历程中的一次重大转折。文中提出"优势替代滞后型式(Pattern of lag of dominance replacement)",专指A组类群的优势被B组类群替代的时间不是紧跟在奥陶纪末大灭绝之后,而是距大灭绝结束约4Ma之后。文中描记新属华夏正形贝(Cathaysiorthis ***.)。

关键词：华夏正形贝动物群残存阶段奥陶纪大灭绝后志留纪初期中国东部

A　Possible　Origin　of　dark　Energy

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Chinese Physics Letters 2004年第6期21卷 1187-1188页

作者： t.d.Lee Physicsdepartment ColumbiaUniversityNewYorkNY10027USA

We discuss the possibility that the existence of dark energy may be due to the presence of a spin zero field φ(x), either elementary or composite. In the presence of other matter field, the transformation φ(x)→φ(x) + constant can generate a negative pressure, like the cosmological constant. In this picture, our universe can be thought as a very large bag, similar to the much smaller MIt bag model for a single nucleon.

关键词： Gravitation and cosmology Particle physics and field theory Astrophysics and astroparticles