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

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Acta Geologica Sinica(English Edition) 2019年第S1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

Effects of Climate Change in the Upper Ordovician of Central Sweden

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地学前缘 2009年第S1期16卷 113-113页

作者： Peter Dahlqvist david a.t.harper Linda M.Wickstrm Geobiosphere Science Centre Lund University Geological Museum University of Copenhagen Geological Survey of Sweden

Late Ordovician shelly faunas occur at several localities in the(O|¨)stersund area of J(a|¨)mtland,central Sweden,an area that today is included in the Lower Allochton of the Swedish *** Late Ordovician faunas of J(a|¨)mtland have developed against a background of intense and rapid global climate *** faunas are present approximately in the middle of the Kyrk(?)s Quartzite in the east and occur in the uppermost Kogsta Siltstone in the west. Changes in faunas and depositional environments provide regional evidence of these global cooling and regressive *** faunas occur in shale and siltstone facies and are used to effect

关键词： Hirnantia Sweden Ordovician climate change

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定量古生物学软件PASt及其常用功能

古生物学报 2013年第2期52卷 161-181页

作者：黄冰 david a.t.harper φyvind Hammer 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 Department of Earth Sciences Durham UniversityDurham DH1 3LEUK Natural History Museum University of OsloP.O.Box 1072 Blindern 0316 OsloNorway

近半个世纪以来,古生物学涉及越来越复杂的现象与过程,难以用传统的经验科学方法来解决。伴随着相关研究引入日益增多的定量分析,古生物学逐渐成为一门可定量分析的科学。作为最早的古生物学专用的免费统计软件包,PASt功能全面、易于使... 详细信息

近半个世纪以来,古生物学涉及越来越复杂的现象与过程,难以用传统的经验科学方法来解决。伴随着相关研究引入日益增多的定量分析,古生物学逐渐成为一门可定量分析的科学。作为最早的古生物学专用的免费统计软件包,PASt功能全面、易于使用,并在过去十几年中发展迅速,目前已在相关软件中占据重要地位。本文在简单介绍该软件基本操作方法的基础上,结合古生物学应用案例,解读最常用到的几类"常规统计分析"与"多元统计分析"的使用;同时,针对古生物学相关领域中的"多样性、丰度及居群结构","形态学"和"生物地层学"问题,给出具体分析实例。在相关案例的分析介绍中,详细梳理用PASt实现这些分析的具体步骤,因而具有较好的实用参考价值。受篇幅所限,文章对软件中其他不常用但相对重要的9个模块只进行简要介绍,以供读者在偶尔涉及该类分析时参考。PASt软件不仅功能强大,而且能够针对古生物学及地层学浮现出来的最新前沿问题不断进行调整、更新,值得在古生物学界推广使用。

关键词： PASt软件定量古生物学多元统计多样性丰度形态学生物地层学

the Global Boundary Stratotype Section and Point （GSSP） for the base of the Hirnantian Stage （the uppermost of the Ordovician System）

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Episodes 2006年第3期29卷 183-196页

作者： Xu Chen Jiayu Rong Junxuan Fan Renbin Zhan Charles E. Mitchell david A. t. harper Michael J. Melchin Ping＇an Peng Stan C. Finney Xiaofeng Wang State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences 39 East Beijing Road Nanjing 210008 China Department of Geology the State University of New York at Buffalo NY 14260-3050 USA. Geological Museum University of Copenhagen Фster Voldgade 5-7 DK-1350 Copenhagen Denmark Department of Earth Sciences St. Francis Xavier University Antigonish N.S. B2G 2W5 Canada State Key Laboratory of Organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Department of Geological Sciences California State University at Long Beach Long Beach CA 90840 USA. Yichang Institute of Geology and Mineral Resources 21 Gangyao Road Yichang 443003 China.

the Global boundary Stratotype Section and Point （GSSP） for the base of the Hirnantian Stage （the uppermost of the Ordovician System） is defined at a point 0.39m below the base of the Kuanyinchiao Bed in the Wangjiawan North section. the section is located near Wangjiawan village, 42 km north of Yichang city （western Hubei, China）, at 30° 58′56″N and 111° 25′10″E. the GSSP level coincides with the first appearance of the graptolite species Normalograptus extraordinarius （Sobolevskaya）. Secondary markers include the onset of a positive carbon-isotope excursion, and a slightly earlier first appearance of Normalograptus ojsuensis （ Koren and Mikhailova ）. the Wangjiawan North section possesses continuity of sedimentation and biozonation with completeness of exposures, abundant and well-preserved graptolites and shelly fossils, i. e. the Hirnantia- Dalmanitina shelly fauna which is a key element for recognition of the Hirnantian Stage. the Wangjiawan North, South and Riverside sections possess favorable facies and widespread correlation potential, are free from structure complication, metamorphism and other alteration, and have good accessibility. the Riverside section in particular possesses amenability to isotopic age determination. the beginning of the Hirnantian was followed by a global episode of a major extinction event, which happened in the Diceratograptus mirus Subzone. the proposal was voted by the International Subcommission on Ordovician Stratigraphy in October, 2004, approved by the International Commission on Stratigraphy in February, 2006, and ratified by the International Union of Geological Sciences in May, 2006.

关键词：全球界线层型剖面和节点奥陶纪 GSSP 地层学

Co-occurrence of Cell Lines, Basal Media and Supplementation in the Biomedical Research Literature

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Journal of Data and Information Science 2020年第3期5卷 161-177页

作者： Jessica Cox Darin McBeath Corey harper Ron Daniel Elsevier Labs 230 Park AvenueNew YorkNY 10169USA

Purpose: the use of in vitro cell culture and experimentation is a cornerstone of biomedical research, however, more attention has recently been given to the potential consequences of using such artificial basal medias and undefined supplements. As a first step towards better understanding and measuring the impact these systems have on experimental results, we use text mining to capture typical research practices and trends around cell ***/methodology/approach: to measure the scale of in vitro cell culture use, we have analyzed a corpus of 94,695 research articles that appear in biomedical research journals published in ScienceDirect from 2000–2018. Central to our investigation is the observation that studies using cell culture describe conditions using the typical sentence structure of cell line, basal media, and supplemented compounds. Here we tag our corpus with a curated list of basal medias and the Cellosaurus ontology using the Aho-Corasick algorithm. We also processed the corpus with Stanford CoreNLP to find nouns that follow the basal media, in an attempt to identify supplements used. Findings: Interestingly, we find that researchers frequently use DMEM even if a cell line's vendor recommends less concentrated media. We see long-tailed distributions for the usage of media and cell lines, with DMEM and RPMI dominating the media, and HEK293, HEK293 t, and HeLa dominating cell lines used. Research limitations: Our analysis was restricted to documents in ScienceDirect, and our text mining method achieved high recall but low precision and mandated manual inspection of many *** implications: Our findings document current cell culture practices in the biomedical research community, which can be used as a resource for future experimental ***/value: No other work has taken a text mining approach to surveying cell culture practices in biomedical research.

关键词： Cell culture Biomedical research text mining

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

DEXA overestimates bone mineral density in adults with knee replacements

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Sports Medicine and Health Science 2020年第4期2卷 211-215页

作者： Katharine D.harper terry A.Clyburn Stephen J.Incavo Bradley S.Lambert Department of Orthopedics&Sports Medicine Houston Methodist Hospital6445 Main StreetOutpatient CenterSuite 2500HoustonTXUnited States Department of Orthopedics Washington DC VA Medical Center50 Irving St.NWWashington D.CUnited States

We examined bone mineral density(BMD)measurements made by dual-energy-xray-absorptiometry(DEXA)taken from 100 patients(♂46/♀54,66±6yr)who previously underwent single total-knee arthroplasty(tKA)to determine if automated software-based artifact detection(ASAD)adequately removes implant artifact from the DXA image before analysis and if potential inaccuracies could be overcome through manual artifact correction(MAC).We also sought to determine if software-based inaccuracies would result in fracture risk misclassification(Low-BMD/Osteopenia=Young-Adult t-Scoret Results:When using ASAD,limbs with implants had higher BMD(+12.0±1.7%,pto control limbs resulting in a 2.5±0.2%overestimation of total-body BMD(single implant).Consequently,the prevalence of osteopenia in 95%of patients who would have been observed to have low leg BMD(18/19 patients)and 80%of those found to have low total-body BMD(4/5 patients)would have gone *** overestimation was eliminated when using *** results reveal a potential issue with ASAD for total-body DEXA scans in tKA patients and highlight the importance of careful review and MAC in those with joint replacements before making diagnostic decisions.

关键词： Dual-energy-xray-absorptiometry DXA DEXA Bone density total joint replacement Arthroplasty Osteopenia Osteoporosis

关于奥陶系最上部赫南特(Hirnantian)亚阶全球层型的建议

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地层学杂志 2000年第3期24卷 176-181页

作者：戎嘉余陈旭哈帕尔(D.a.t.harper) 米切尔(C.E.Mitchell) 中国科学院南京地质古生物研究所江苏南京210008 丹麦哥本哈根大学地质博物馆美国纽约州立大学地质系布法罗ny142603050

在对鄂西宜昌王家湾和分乡、黔北桐梓红花园、黔东北松桃陆地坪 4条剖面的相关地层和主要门类化石做了新的无间断采集和重新鉴定笔石和腕足动物这两个重要化石门类的基础上 ,发现奥陶纪最末期—志留纪最早期的完整笔石序列与腕足动物等... 详细信息

在对鄂西宜昌王家湾和分乡、黔北桐梓红花园、黔东北松桃陆地坪 4条剖面的相关地层和主要门类化石做了新的无间断采集和重新鉴定笔石和腕足动物这两个重要化石门类的基础上 ,发现奥陶纪最末期—志留纪最早期的完整笔石序列与腕足动物等新的化石材料 ,初步了解奥陶纪末集群灭绝后生物幸存的基本特征。经过选择 ,特推荐宜昌王家湾公路旁穿越奥陶 -志留纪界线地层剖面作为建立国际赫南特亚阶的首位候选 (leading candidate)层型 ,并推荐桐梓红花园相关剖面作为辅助候选 (auxiliary candidate)层型。对建立全球赫南特亚阶界线层型的基本条件和国外相关剖面的优缺点作了分析。本文所识别的赫南特亚阶相当于两个笔石带 :下部 N ormalograptus ex-traordinarius- ***带和上部 ***带。典型的 H irnantia动物群的整体地质历程为奥陶纪最末期 ,相当于 N ormalograptus extraordinarius- ***带和 ***带的一部分。

关键词：奥陶纪赫南特亚阶层型候选剖面

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