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Ecosystem service delivery in Karst landscapes： anthropogenic perturbation and recovery

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Acta Geochimica 2017年第3期36卷 416-420页

作者： Timothy Quine Dali Guo Sophie m.green Chenglong Tu Iain Hartley Xinyu Zhang Jennifer Dungait Xuefa Wen Zhaoliang Song Hongyan Liu Heather Buss Timothy Barrows richard Evershed Penny Johnes Jeroen meersmans Geography College of Life and Environmental SciencesUniversity of Exeter Rennes Drive Exeter EX4 4RJ UK Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 People's Republic of China State Key Laboratory of Environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 550081 Guizhou Province People's Republic of China Rothamsted Research - North Wyke Okehampton Devon EX20 2SB UK Institute of the Surface-Earth System Science Research Tianjin University Tianjin 300072 People's Republic of China College of Urban and Environmental Sciences Peking University Beijing 100871 People's Republic of China School of Earth Sciences Wills Memorial Building Queens Road Clifton BS8 1RJ UK School of Chemistry University of Bristol Cantock's Close Clifton Bristol BS8 1TS UK School of Geographical Sciences University of BristolUniversity Road Clifton Bristol BS8 1SS UK Cranfield Soil and Agrifood Institute Cranfield UniversityCranfield Bedfordshire MK43 0AL UK

Covering extensive parts of China, Karst landscapes are exceptional because rapid and intensive land use change has caused severe ecosystem degradation within only the last 50 years. The twentieth century intensification in food production through agriculture has led to a rapid deterioration of soil quality, evidenced in reduced crop production and rapid loss of soil. In many areas, a tipping point appears to have been passed as basement rock is exposed and 'rocky desertification' dominates. Through the establishment of the "Soil processes and ecological services in the karst critical zone of SW China"(SPECTRA)Critical Zone Observatory(CZO) we will endevaour to understand the fundmental processes involved in soil production and erosion, and investigate the integrated geophysical-geochemical-ecological responses of the CZ to perturbations. The CZ spans a gradient from undisturbed natural vegetation through human perturbed *** seek to understand the importance of heterogeneity insurface and below-ground morphology and flow pathways in determining the spatial distribution of key stocks(soil,C, vegetation, etc.) and their control on ecosystem service delivery. We will assess the extent to which the highly heterogeneous critical zone resources can be restored to enable sustainable delivery of ecosystem services. This paper presents the CZO design and initial assessment of soil and soil organic carbon stocks and evidence for their stability based on caesium-137(^(137) Cs) data.

关键词： Soil degradation Ecosystem services Caesium-137 Karst,China

Recurrent gastrointestinal bleeding and hepatic infarction after liver biopsy

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World Journal of Gastroenterology 2014年第7期20卷 1878-1881页

作者： Faraz Bishehsari Peng-Sheng Ting richard m.green Division of Gastroenterology and Hepatology Feinberg School of MedicineRobert H.Lurie Comprehensive Cancer CenterNorthwestern University Department of medicine National Taiwan University College of Medicine

Hepatic artery pseudoaneurysms(HAP)are rare events,particularly after liver biopsy,but can be associated with serious *** a high suspicion is necessary for timely diagnosis and appropriate *** report on a case of HAP that potentially formed after a liver biopsy in a patient with *** HAP in our case was virtually undetectable initially by angiography but resulted in several complications including recurrent gastrointestinal bleeding,hemorrhagic cholecystitis and finally hepatic infarction with abscess formation until it became detectable at a size of *** patient remains asymptomatic over a year after endovascular embolization of the *** this report,we demonstrate that a small HAP can avoid detection by angiography at an early stage while being symptomatic for a prolonged course.A high clinical suspicion with a close clinical/radiological follow-up is needed in symptomatic patients with history of liver biopsy despite initial negative work *** diagnosed,HAP can be safely and effectively treated by endovascular embolization.

关键词： Gastrointestinal bleed Abnormal liver enzymes Hepatic artery pseudoaneurysms Liver biopsy Angiography

International financial markets : : prices and policies / richard m. Levich. 2nd ed.

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Understanding Science Through the Computational Lens

2001年

作者： Levich richard m.

来源：畅想之星图书光盘版（南... 评论

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Journal of Computer Science & Technology 2011年第4期26卷 569-577页

作者： richard m.Karp Department of Electrical Engineering and Computer Sciences University of California

This article explores the changing nature of the interaction between computer science and the natural and social sciences. After briefly tracing the history of scientific computation, the article presents the concept of computational lens, a metaphor for a new relationship that is emerging between the world of computation and the world of the sciences. Our main thesis is that, in many scientific fields, the processes being studied can be viewed as computational in nature, in the sense that the processes perform dynamic transformations on information represented as digital data. Viewing natural or engineered systems through the lens of their computational requirements or capabilities provides new insights and ways of thinking. A number of examples are discussed in support of this thesis. The examples are from various fields, including quantum computing, statistical physics, the World Wide Web and the Internet, mathematics, and computational molecular biology.

关键词： computational process computer science and other sciences computational lens

metamorphic consequences of secular changes in oceanic crust composition and implications for uniformitarianism in the geological record

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Geoscience Frontiers 2018年第4期9卷 1009-1019页

作者： richard m.Palin Brendan Dyck Department of Geology and Geological Engineering Colorado School of Mines Department of Earth Sciences Simon Fraser University

Cooling of the Earth＇s mantle since the meso-Archean is predicted by thermal and petrological models to have induced a secular change in the composition of primary mantle-derived magmas-and thus bulk oceanic crust; in particular, suggesting a decrease in maficity over time. This hypothesis underpins several recent studies that have addressed key geological questions concerning evolving plate tectonic styles, the rates and timing of continental crust formation, comparative planetology, and the emergence of complex life on Earth. major, minor, and trace element geochemical analyses of（meta）mafic rocks preserved in the geological record allows exploration of this theory, although no consensus currently exists about the magnitude of this change and what compositions-if anything-constitute representative examples of Paleo-, meso-, or Neo-Archean primitive oceanic crust. In this work, we review the current state of understanding of this issue, and use phase equilibria to examine the different mineral assemblages and rock types that would form during metamorphism of basalt of varying maficity in subduction zone environments. The presence（or absence） of such metamorphic products in the geological record is often used as evidence for（or against） the operation of modern-day subductiondriven plate tectonics on Earth at particular time periods; however, the control that secular changes in composition have on the stability of mineral assemblages diagnostic of subduction-zone metamorphism weakens such uniformitarianistic approaches. Geodynamic interpretations of the Archean metamorphic rock record must therefore employ a different set of petrological criteria for determining tectonothermal histories than those applied to Proterozoic or Phanerozoic equivalents.

关键词： Archean mantle cooling Oceanic crust Basalt metamorphism Uniformitarianism

What we have learned from randomized trials of prostate cancer screening

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Asian Journal of Andrology 2011年第3期13卷 369-373,510页

作者： richard m Hoffman Anthony Y Smith medicine Service New Mexico VA Health Care System Albuquerque NM 87108 USA Department of medicine University of New Mexico School of Medicine Albuquerque NM 87108 USA Department of Surgery University of New Mexico School of Medicine Albuquerque NM 87108 USA

The introduction of prostate-specific antigen （PSA） for prostate cancer screening in the late 1980s led to an epidemic of prostate cancer, particularly in developed countries. However, the first valid reports from randomized controlled trials on the efficacy of screening were not published until 2009. men in the screening group in the European Randomized Study of Screening for Prostate Cancer were 20% less likely than those in the control group to die from prostate cancer. The absolute difference was only 0.7/1000, implying that over 1400 men needed to be screened to prevent one prostate cancer death. Screening was also associated with a 70% increased risk for being diagnosed with prostate cancer. The American Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial found no survival benefit for screening. Results were not conclusive because a substantial proportion of study subjects had previously undergone PSA testing, over half of the control group had PSA testing, follow-up was relatively short, and fewer than 100 subjects died from prostate cancer. Balancing the potential survival benefit from screening is the risk of overdiagnosis--finding cancers that would not otherwise cause clinical problems^and the risk of treatment complications, including urinary, sexual and bowel dysfunction. Prostate cancer screening efforts would benefit from improved biomarkers, which more readily identify clinically important cancers. Cancer control efforts might also need to include chemoprevention, though currently available agents are controversial. In the meantime, oatients need to be supoorted in achievine informed decisions on whether to be screened for orostate cancer.

关键词： cancer screening prostate-specific antigen prostatic neoplasms randomized controlled trials as topic

Seismic performance of steel mRF building with nonlinear viscous dampers

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Frontiers of Structural and Civil Engineering 2016年第3期10卷 254-271页

作者： Baiping DONG James m. RICLES richard SAUSE ATLSS Engineering Research Center Department of Civil and Environmental Engineering Lehigh University Bethlehem PA 18015 USA

This paper presents an experimental study of the seismic response of a 0.6-scale three-story seismicresistant building structure consisting of a moment resisting frame （mRF） with reduced beam sections （RBS）, and a frame with nonlinear viscous dampers and associated bracing （called the DBF）. The emphasis is on assessing the seismic performance for the design basis earthquake （DBE） and maximum considered earthquake （mCE）. Three mRF designs were studied, with the mRF designed for 100%, 75%, and 60%, respectively, of the required base shear design strength determined according to ASCE 7-10. The DBF with nonlinear viscous dampers was designed to control the lateral drift demands. Earthquake simulations using ensembles of DBE and mCE ground motions were conducted using the real-time hybrid simulation method. The results show the drift demand and damage that occurs in the mRF under seismic loading. Overall, the results show that a high level of seismic performance can be achieved under DBE and mCE ground motions, even for a building structure designed for as little as 60% of the base shear design strength required by ASCE 7-10 for a structure without dampers.

关键词： seismic response steel mRF nonlinear viscous damper design basis earthquake real-time hybrid simulation

The dilemma of the Jiaodong gold deposits: Are they unique?

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Geoscience Frontiers 2014年第2期5卷 139-153页

作者： richard J.Goldfarb m.Santosh U.S.Geological Survey Box 25046 MS 973 Denver Federal Center State Key Laboratory of Geological Processes and mineral Resources School of Earth Sciences and Resources China University of Geosciences Centre for Exploration Targeting School of Earth and Geographical Sciences University of Western Australia Crawley

The ca. 126e120 ma Au deposits of the Jiaodong Peninsula, eastern China, define the country＇s largest gold province with an overall endowment estimated as＆gt;3000 t Au. The vein and disseminated ores are hosted by NE-to NNE-trending brittle normal faults that parallel the margins of ca. 165e150 ma, deeply emplaced, lower crustal melt granites. The deposits are sited along the faults for many tens of kilometers and the larger orebodies are associated with dilatational jogs. Country rocks to the granites are Pre-cambrian high-grade metamorphic rocks located on both sides of a Triassic suture between the North and South China blocks. During early mesozoic convergent deformation, the ore-hosting structures developed as ductile thrust faults that were subsequently reactivated during Early Cretaceous ＂Yan-shanian＂intracontinental extensional deformation and associated gold formation. 〈br〉 Classification of the gold deposits remains problematic. many features resemble those typical of orogenic Au including the linear structural distribution of the deposits, mineralization style, ore and alteration assemblages, and ore fluid chemistry. However, Phanerozoic orogenic Au deposits are formed by prograde metamorphism of accreted oceanic rocks in Cordilleran-style orogens. The Jiaodong de-posits, in contrast, formed within two Precambrian blocks approximately 2 billion years after devolati-lization of the country rocks, and thus require a model that involves alternative fluid and metal sources for the ores. A widespread suite of ca. 130e123 ma granodiorites overlaps temporally with the ores, but shows a poor spatial association with the deposits. Furthermore, the deposit distribution and mineral-ization style is atypical of ores formed from nearby magmas. The ore concentration requires fluid focusing during some type of sub-crustal thermal event, which could be broadly related to a combination of coeval lithospheric thinning, asthenospheric upwelling, paleo-Pacific plate subducti

关键词： Gold Jiaodong North China block Tectonics mineral deposit mode

Storylines of family medicine Ⅰ:framing family medicine–history,values and perspectives

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Family medicine and Community Health 2024年第S03期12卷 2-11页

作者： William B Ventres Leslie A Stone Kathleen T Rowland richard H Streiffer michael D macechko Julia A Roulier Jeffrey m Borkan Larry A green Family and Preventive medicine University of Arkansas for Medical Sciences College of MedicineLittle RockArkansasUSA Family and Preventive medicine Rush Medical College of Rush UniversityChicagoIllinoisUSA College of Community Health Sciences University of AlabamaTuscaloosaAlabamaUSA UAmS Northwest Regional Campus Family medicine Residency Program FayettevilleArkansasUSA UAmS North Central Regional Campus Family medicine Residency Program BatesvilleArkansasUSA Family medicine Brown University Warren Alpert Medical SchoolProvidenceRhode IslandUSA University of Colorado School of medicine AuroraColoradoUSA

Storylines of Family medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine,as interpreted by individual family physicians and medical educators in the USA and elsewhere around the ***‘Ⅰ:framing family medicine—history,values,and perspectives’,the authors address the following themes:‘Notes on Storylines of Family medicine’,‘Family medicine—the generalist specialty’,‘Family medicine’s achievements—a glass half full assessment’,‘Family medicine’s next 50 years—toward filling our glasses’,‘Four enduring truths of family medicine’,‘Names matter’,‘Family medicine at its core’and‘The ecology of medical care.’may readers find much food for thought in these essays.

关键词： glasses illustration Notes