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The giant Jiaodong gold province： The key to a unified model for orogenic gold deposits？

Geoscience Frontiers 2016年第3期7卷 409-417页

作者： david I.Groves m.Santosh Centre for Exploration Targeting UWA Cmwley 6009 WA Australia Centre for Tectonics Resources and Exploration Department of Earth Sciences University of Adelaicle SA 5005 Australia State Key Laboratory of Geological Processes and mineral Resources China University of Geosciences Beijing 100083 China Division of Interdisciplinary Science Faculty of Science Kochi University Kochi 780-8520 Japan

Although the term orogenic gold deposit has been widely accepted for all gold-only lode-gold deposits,with the exception of Carlin-type deposits and rare intrusion-related gold systems,there has been continuing debate on their *** syngenetic models and hydrothermal models dominated by meteoric fluids are now clearly ***-hydrothermal models fail to explain the genesis of orogenic gold deposits because of the lack of consistent spatially- associated granitic intrusions and inconsistent temporal *** most plausible,and widely accepted,models involve metamorphic fluids,but the source of these fluids is hotly *** within deeper segments of the supracrustal successions hosting the deposits,the underlying continental crust,and subducted oceanic lithosphere and its overlying sediment wedge all have their *** orogenic gold deposits of the giant Jiaodong gold province of China,in the delaminated North China Craton,contain ca.120 ma gold deposits in Precambrian crust that was metamorphosed over 2000 million years prior to gold *** only realistic source of fluid and gold is a subducted oceanic slab with its overlying sulfide-rich sedimentary package,or the associated mantle *** could be viewed as an exception to a general metamorphic model where orogenic gold has been derived during greenschist- to amphibolite-facies metamorphism of supracrustal rocks：basaltic rocks in the Precambrian and sedimentary rocks in the ***,if a holistic view is taken,Jiaodong can be considered the key orogenic gold province for a unified model in which gold is derived from late-orogenic metamorphic devolatilization of stalled subduction slabs and oceanic sediments throughout Earth *** latter model satisfies all geological,geochronological,isotopic and geochemical constraints but the precise mechanisms of auriferous fluid release,like many other subduction-related processes,are model-driv

关键词： Jiaodong province Orogenic gold metamorphic fluids Subduction zones Tectonics

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Dendroclimatic response of Abies spectabilis at treeline ecotone of Barun Valley, eastern Nepal Himalaya

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Journal of Forestry Research 2016年第5期27卷 1163-1170页

作者： Parveen Kumar Chhetri david m.Cairns Department of Geography Texas A&M UniversityCollege StationTX 77843-3147USA

A dendroclimatic study was conducted in the treeline ecotone of Barun Valley, eastern Nepal, to determine the tree-ring climate response and ring width trend of Abies spectabilis. A 160-year-old chronology, from 1850 to 2010, was developed from 38 tree-ring samples. No higher growth in recent decades was observed in tree-ring width in this area. The mean temperature of the current year in February and in the combined winter months of December, January, and February showed significant positive correlation with tree-ring width, although no significant correlation was found between tree-ring width and the precipitation pattern of the region. This tree-ring climate response result is different from that in other studies in Nepal, which could be attributed to location and elevation.

关键词： spectabilis Dendroclimatology Treeline ecotone Abies Climate response Tree-ring width

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Dynamic Bubble Behaviour during microscale Subcooled Boiling

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Chinese Physics Letters 2005年第11期22卷 2881-2884页

作者：王昊彭晓峰 david m. Christopher Laboratory of Phase-Change and Interracial Transport Phenomena Department of Thermal Engineering Tsinghua University Beijing 100084

Bubble cycles, including initiation, growth and departure, are the physical basis of nucleate boiling. The present investigation, however, reveals unusual bubble motions during subcooled nucleate boiling on microwires 25 or 100μm in diameter. Two types of bubble motions, bubble sweeping and bubble return, are observed in the experiments. Bubble sweeping describes a bubble moving back and forth along the wire, which is motion parallel to the wire. Bubble return is the bubble moving back to the wire after it has detached or leaping above the wire. Theoretical analyses and numerical simulations are conducted to investigate the driving mechanisms for both bubble sweeping and return. marangoni flow from warm to cool regions along the bubble interface is found to produce the shear stresses needed to drive these unusual bubble movements.

关键词： subcooled boiling ELECTRIC WIRE driving mechanism bubbles Nucleate boiling Shear stress

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Communication,Computation,and Governance:A multiscalar Vantage on the Prehispanic mesoamerican World

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Journal of Social Computing 2022年第1期3卷 91-118页

作者： Gary m.Feinman david m.Carballo the Negaunee Integrative Research Center Field Museum of Natural HistoryChicagoIL 60605USA Anthropology Archaeologyand Latin American StudiesBoston UniversityBostonMA 02215USA

Writing has often been put forth as one indicator of *** correspondence dovetails with the even broader cross-species expectation that the degrees of social complexity and levels of computational communication should closely *** in a general sense across human cooperative arrangements,a basic relationship between these variables undoubtedly exists,more detailed and fine-grained analyses indicate important axes of ***,our focus is on prehispanic mesoamerica and the means of computation and communication employed over more than three millennia(ca.1500 BCE-1520 CE).We take a multiscalar and diachronic analytical frame,in which we look at 30 central places,six macroregions,and mesoamerica as *** unraveling elements of“social complexity”,and decoupling computation from communication,we illustrate that institutional differences in governance had a marked effect on the specific modes and technologies through which prehispanic mesoamerican peoples communicated across time and *** and spatial scale,though relevant,do not alone determine time/space diversity in media of computational *** article is part of the theme issue“Evolution of Collective Computational Abilities of(Pre)Historic Societies”.

关键词： mesoamerica archaeology communication computation writing polity scale calendrics maya Aztec

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Stricter national standards are required for credentialing of endoscopic-retrograde-cholangiopan-creatography in the United States

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World Journal of Gastroenterology 2019年第27期25卷 3468-3483页

作者： mitchell S Cappell david m Friedel Division of Gastroenterology and Hepatology William Beaumont HospitalRoyal OakMI 48073United States Oakland University William Beaumont School of medicine William Beaumont HospitalMI 48073United States Division of Gastroenterology New York University Winthrop Medical CenterMineolaNY 11501United States

Endoscopic-retrograde-cholangiopancreatography(ERCP) is now a vital modality with primarily therapeutic and occasionally solely diagnostic utility for numerous biliary/pancreatic disorders. It has a significantly steeper learning curve than that for other standard gastrointestinal(GI) endoscopies, such as esophagogastroduodenoscopy or colonoscopy, due to greater technical difficulty and higher risk of complications. Yet, GI fellows have limited exposure to ERCP during standard-three-year-GI-fellowships because ERCP is much less frequently performed than esophagogastroduodenoscopy/colonoscopy. This led to adding an optional year of training in therapeutic endoscopy. Yet many graduates from standard three-year-fellowships without advanced training intensely pursue independent/unsupervised ERCP privileges despite inadequate numbers of performed ERCPs and unacceptably low rates of successful selective cannulation of desired(biliary or pancreatic) duct. Hospital credentialing committees have traditionally performed ERCP credentialing, but this practice has led to widespread flouting of recommended guidelines(e.g., planned privileging of applicant with 20% successful cannulation rate, or after performing only 7 ERCPs);and intense politicking of committee members by applicants, their practice groups, and potential competitors. Consequently, some gastroenterologists upon completing standard fellowships train and learn ERCP 'on the job' during independent/unsupervised practice, which can result in bad outcomes: high rates of failed bile duct cannulation. This severe clinical problem is indicated by publication of ≥ 12 ERCP competency studies/guidelines during last 5 years. However, lack of mandatory, quantitative, ERCP credentialing criteria has permitted neglect of recommended guidelines. This work comprehensively reviews literature on ERCP credentialing;reviews rationales for proposed guidelines;reports problems with current system;and proposes novel criteria for competenc

关键词： Endoscopic retrograde cholangiopancreatography Privileges Credentialing Gastroenterology fellowship training Advanced gastrointestinal endoscopy training Certification Standards

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Determinants of male health： the interaction of biological and social factors

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Asian Journal of Andrology 2010年第3期12卷 291-297,I0007页

作者： david m. de Kretser（澳大利亚） monash University Clayton Victoria 3168 Australia

This review discusses the social and biological factors that may influence male development from conception to adulthood and also underlie the development of health disorders. It will provide assistance to those who may be considering the formulation of a male health policy. It aims to emphasize that social determinants function on a bio- logical background that is profoundly influenced by a male＇s genome, inherited from his parents. The importance of the male-specific reproductive disorders is emphasized, but these also affect somatic structures through the secretion of androgens secreted from the testes. In turn, the function of the cardiovascular and nervous systems can signifi- cantly influence reproductive processes such as erectile dysfunction.

关键词： infertility genetics impotence health policy

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THE DEmOCRATIC CONTROL OF PUBLIC SPENDING IN CLASSICAL ATHENS

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Journal of Ancient Civilizations 2019年第2期34卷 229-243,329页

作者： david m Pritchard L’Universitéde Lyon/The University of Queensland

This article challenges the famous argument of Lisa Kallet that the Athenian people did not understand public *** argues that the dēmos(“people”)had the necessary general knowledge and the necessary understanding of the state’s budget to make independent financial *** democratic council and politicians kept them well informed on the overall fiscal position of *** adjudicating public debates about the state’s budget they learnt a great deal about public *** time the votes that they cast in such debates came to reflect their own priorities for their *** the sums that Athenian democracy spent on different activities reflected the preferences of,not politicians,as Kallet argued,but the dēmos themselves.

关键词： CLASS argument reflected

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Field Phenomics:Will It Enable Crop Improvement?

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Plant Phenomics 2021年第1期3卷 310-325页

作者： david m.Deery Hamlyn G.Jones CSIRO Agriculture and Food CanberraACTAustralia Division of Plant Sciences University of DundeeUK School of Agriculture and Environment University of Western AustraliaAustralia

Field phenomics has been identified as a promising enabling technology to assist plant breeders with the development of improved cultivars for ***,despite much investment,there are few examples demonstrating the application of phenomics within a plant breeding *** review recent progress in field phenomics and highlight the importance of targeting breeders’needs,rather than perceived technology needs,through developing and enhancing partnerships between phenomics researchers and plant breeders.

关键词： breeding cultivar Crop

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Influence of humidity on conduction processes in gas-insulated devices

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High Voltage 2020年第2期5卷 143-150页

作者： malte Tschentscher david Graber Christian m.Franck High Voltage Laboratory ETH Zurich8092 ZurichSwitzerland

Humidity has been considered as one of the main influencing factors that determine the conduction processes and electric strength of gas-insulated *** in the past,various studies focused on the change in the partial discharge inception voltages,breakdown strength of homogeneous and inhomogeneous field arrangements,and insulator flashover voltage,recent studies have investigated the changes in ion currents measured through different gas *** the framework of this contribution,a highly precise humidity control circuit has been developed to analyse the significance of humidity in the range from−25 to−5°C frost-point,which is fully applicable to operating gas-insulated *** sulphur hexafluoride(SF6)as the insulation gas at 0.45 mPa,Al2O3-filled epoxy resin insulators,and technically rough electrodes,the humidity was found to significantly influence the intensity of microdischarges at *** generation from microdischarges at the interfaces substantially increased with increasing *** an electric field of 5 kV/mm that were applicable to the dimensioning of gas-insulated devices,humidity strongly influences the charge provision from technically rough interfaces and potentially contributes to the surface-charge accumulation at insulator *** the other hand,for low-field conduction phenomena,no increase in the ion currents from natural ionisation or electrophoretic conduction was *** the investigated range of parameters,humidity is expected to be highly relevant for the design of gas-insulated devices.

关键词： conduction humidity sulphur

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Cost-Effectiveness of Interventions for Alternate Food to Address Agricultural Catastrophes Globally

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International Journal of Disaster Risk Science 2016年第3期7卷 205-215页

作者： david C.Denkenberger Joshua m.Pearce Global Catastrophic Risk Institute Department of Civil and Architectural Engineering Tennessee State University Department of materials Science and Engineering Michigan Technological University Department of Electrical and Computer Engineering Michigan Technological University

The literature suggests there is about a 1 % risk per year of a 10 % global agricultural shortfall due to catastrophes such as a large volcanic eruption, a medium asteroid or comet impact, regional nuclear war, abrupt climate change, and extreme weather causing multiple breadbasket failures. This shortfall has an expected mortality of about 500 million people. To prevent such mass starvation, alternate foods can be deployed that utilize stored biomass. This study developed a model with literature values for variables and, where no values existed,used large error bounds to recognize uncertainty. Then monte Carlo analysis was performed on three interventions: planning, research, and development. The results show that even the upper bound of USD 400 per life saved by these interventions is far lower than what is typically paid to save a life in a less-developed country. Furthermore, every day of delay on the implementation of these interventions costs 100–40,000 expected lives(number of lives saved multiplied by the probability that alternate foods would be required). These interventions plus training would save 1–300 million expected lives. In general, these solutions would reduce the possibility of civilization collapse, could assist in providing food outside of catastrophic situations, and would result in billions of dollars per year of return.

关键词： Agricultural catastrophe Alternate food Global catastrophic risk Intervention cost-effectiveness

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