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过度诊断：什么是，什么不是

英国医学杂志中文版 2018年第10期21卷 546-548页

作者： John Brodersen Lisa M Schwartz Carl Heneghan jack william o' sullivan Jeffrey K Aronson Steven Woloshin 柳芳超(译) 刘珏(译) 刘民(校) Centre of Research & Education in General Practice Department of Public Health University of Copenhagen. Faculty of Health Sciences Copenhagen Denmark Region Zealand Primary Health Care Research Unit Center for Medicine and the Media The Dartmouth Institute for Health Policy and Clinical Practice Dartmouth Medical School Lebanon New Hampshire USA Centre for Evidence-Based Medicine Nuffield Department of Primary Care Heahh Sciences University of Oxford Oxford UK 北京大学公共卫生学院

那么，好的东西会嫌太多吗？——《皆大欢喜》（As You Likeh）莎士比亚（公元1600年）罗莎琳德在要嫁给奥兰多时提出的这个问题仅仅是一种反问——她认为不能对好东西过度享用。然而，尽管俗套，一个人有时候就是会过度享用。在医疗保... 详细信息

那么，好的东西会嫌太多吗？——《皆大欢喜》（As You Likeh）莎士比亚（公元1600年）罗莎琳德在要嫁给奥兰多时提出的这个问题仅仅是一种反问——她认为不能对好东西过度享用。然而，尽管俗套，一个人有时候就是会过度享用。在医疗保健领域更是如此，目前已被称为“过度医疗”。尽管它容易和“过度用药”相混淆，更好的说法应该是“过度医疗保健”。

关键词：过度诊断医疗卫生行业发展现状医生

Tissue engineering in mandibular reconstruction: osteogenesis-inducing scaffolds

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Plastic and Aesthetic Research 2019年第9期6卷 1-12页

作者： Laurel Nelms william jack Palmer University of California Riverside School of Medicine RiversideCA 92521USA Boston University School of Medicine BostonMA 02118USA.

Currently, the gold standard for aesthetic and functional reconstruction of critical mandibular defects is an autologous fibular flap;however, this carries risk of donor site morbidity, and is not a promising option in patients with depleted donor sites due to previous surgeries. Tissue engineering presents a potential solution in the design of a biomimetic scaffold that must be osteoconductive, osteoinductive, and support osseointegration. These osteogenesis-inducing scaffolds are most successful when they mimic and interact with the surrounding native macro- and micro-environment of the mandible. This is accomplished via the regeneration triad: (1) a biomimetic, bioactive osteointegrative scaffold, most likely a resorbable composite of collagen or a synthetic polymer with collagen-like properties combined with beta-tri calcium phosphate that is 3D printed according to defect morphology;(2) growth factor, most frequently bone morphogenic protein 2 (BMP-2);and (3) stem cells, most commonly bone marrow mesenchymal stem cells. Novel techniques for scaffold modification include the use of nano-hydroxyapatite, or combining a vector with a biomaterial to create a gene activated matrix that produces proteins of interest (typically BMP-2) to support osteogenesis. Here, we review the current literature in tissue engineering in order to discuss the success of varying use and combinations of scaffolding materials (i.e., ceramics, biological polymers, and synthetic polymers) with stem cells and growth factors, and will examine their success in vitro and in vivo to induce and guide osteogenesis in mandibular defects.

关键词： osteogenic scaffolds mandibular reconstruction tissue engineering regeneration triad bone morphogenic protein bone marrow mesenchymal stem cells beta-tri calcium phosphate gene activated matrix

Will biomass be used for bioenergy or transportation biofuels? What drivers will influence biomass allocation

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Frontiers of Agricultural Science and Engineering 2017年第4期4卷 473-481页

作者： Jinguang HU william James CADHAM Susan van DYK jack N.SADDLER Department of Wood Science Faculty of Forestry The University of British Columbia

Potential competition for biomass for current and future bioenergy/biofuel uses in Brazil, Denmark,Sweden and the USA were compared. In each of these countries, bioenergy and biofuels are already important in their energy mix. However, there is limited competition for biomass between bioenergy(heat/power/residential/industrial) and transportation biofuel applications. This situation is likely to continue until advanced biofuel technology becomes much more commercially established. In each of these countries, biomass is predominantly used to produce bioenergy, even in those regions where biofuels are significant component of their transportation sector(Brazil,Sweden and USA). The vast majority of biofuel production continues to be based on sugar, starch and oil rich feedstocks, while bioenergyis produced almost exclusively from forest biomass with agricultural biomass having a small, but increasing, secondary role. Current and proposed commercial scale biomass-to-ethanol facilities almost exclusively use agriculture derived residues(corn stover/wheat straw/sugarcane bagasse). Competition for biomass feedstocks for bioenergy/biofuel applications, is most likely to occur for agricultural biomass with coproduct lignin and other residues used to concomitantly produce heat and electricity on site at biofuel production facilities.

关键词： bioenergy biofuel biomass renewable energy policy

Effect of cylinder wall parameters on the final packing density of mono-disperse spheres subject to three-dimensional vibrations Author links open overlay panel

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Particuology 2024年第8期91卷 211-225页

作者： jack R.Grogan Andrei L.Nicuşan Christopher R.K.Windows-Yule School of Chemical Engineering The University of BirminghamEdgbastonBirminghamB152TTUK

Achieving densely packed particles is desirable within the industries of ceramics,pharmaceuticals,defence and additive *** this work,we use the discrete element method(DEM)to determine the effect of wall parameters on the final packing density of mono-disperse spheres subject to 4 varying three-dimensional vibration and fill *** focus specifically on the impact of the container wall parameters on the particles'final packing *** on from the validation of the DEM simulation the particle-wall coefficient of restitution,the particle-wall coefficient of rolling friction and the particle-wall coefficient of sliding friction were varied individually and the effect on the final packing density *** relatively low particle-particle friction glass beads,the effect of these wall properties had no discernible effect on the final packing density *** on from these findings the particle-wall properties were varied at the extreme values of particle-particle coefficient of rolling friction and particle-particle coefficient of sliding *** a particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of restitution resulted in a minor increase in the final packing density of particles though this was not statistically *** a particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of rolling friction resulted in a minor decrease in the final packing density of the particles though again not to a degree where the trend can,with complete certainty,be distinguished from the random error across the ***,when the particle-particle coefficient of sliding friction=1,increases in particle-wall coefficient of sliding friction resulted in a significant decrease in the final packing density of *** decrease was attributed to the propagation of force chains throughout the *** significant decrease in final packing density with

关键词： Vibropacking Packing Densification Vibration Discrete element method Friction Wall friction Restitution

Climate change effects on rangelands and rangeland management:affirming the need for monitoring

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Ecosystem Health and Sustainability 2017年第3期3卷 1-14页

作者： Daniel W.McCollum John A.Tanaka jack A.Morgan John E.Mitchell william E.Fox Kristie A.Maczko Lori Hidinger Clifford S.Duke Urs P.Kreuter Rocky Mountain Research Station USDAForest Service240 W.Prospect RoadFort CollinsColorado 80526 USA James C.Hageman Sustainable Agriculture Research and Extension Center University of WyomingDept 33541000 E.University AvenueLaramieWyoming 82071 USA USDA ARS Rangelands Resources Research Unit8408 Hildreth RoadCheyenneWyoming 82009 USA Texas A&M AgriLife Research Ecosystem Science&Management720 E.Blackland RoadTempleTexas 76502 USA Consortium for Science Policyand OutcomesArizona State UniversityPO Box 875603TempeArizona 85287 USA Ecological Society of America 1990 M StreetNWSuite 700WashingtonD.C.20036 USA Ecosystem Science and Management Texas A&M University2138 TAMUCollege StationTexas 77843 USA

Uncertainty as to the extent and magnitude of changes in conditions that might occur due to climate change poses a problem for land and resource managers as they seek to adapt to changes and mitigate effects of climate *** illustrate using scenarios of projected future conditions on rangelands in the Northern Great Plains and Desert Southwest of the United *** two regions are different in the ways climate change is projected to affect the *** of a longer and warmer growing season in the Northern Great Plains could lead to increased forage production and land *** uncertain effects on summer monsoons that primarily control rangeland productivity in the Desert Southwest,combined with the possibility of more intense and/or frequent drought events,could present land managers with challenges stemming from decreased forage production and land *** projections,though uncertain,provide land managers with basic insight into future conditions they might *** need more.A focus on vulnerability and resilience,with explicit recognition of interactions between ecological and socio-economic factors,coupled with systematic monitoring and assessment of observable conditions on the land to supplement information based on climate projections,will more effectively provide critical and specific information managers need to adaptively manage rangelands under uncertain climate futures.

关键词： adaptive management climate change indicators monitoring rangelands resilience uncertainty vulnerability

Aircraft Engine Design, Second Edition 2nd ed.

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The Tidal Stream Power Curve: A Case Study

丛书名： AIAA Education Series

2002年

作者： jack D. Mattingly william H. Heiser David T. Pratt

ISBN: (数字)9781600861444

ISBN: (纸本)9781563475382

Winner of the Summerfield Book Award! The text presents a complete and realistic aircraft engine design experience. From the request for proposal for a new aircraft to the final engine layout, the book provides the concepts and procedures required for the entire process. It is a significantly expanded and modernized version of the best-selling first edition that emphasizes recent developments impacting engine design such as theta break-throttle ratio, life management, controls, and stealth. The key steps of the process are detailed in 10 chapters that encompass aircraft constraint analysis, aircraft mission analysis, engine parametric (design point) analysis, engine performance (off-design) analysis, engine installation drag and sizing, and the design of inlets, fans, compressors, main combustors, turbines, afterburners, and exhaust *** AEDsys software that accompanies the text provides comprehensive computational support for every design step. The software has been carefully integrated with the text to enhance both the learning process and productivity, and allows effortless transfer between British engineering and SI units. The AEDsys software is furnished on CD-RoM and runs on the Windows operating system. A user’s manual is provided with the software, along with the complete data files used for the Air-to-Air Fighter and Global Range Airlifter design examples of the book.

关键词： Aircraft Engines Combustion Chambers Combustors Nozzles Propulsion and Power Rocket Engine Rocketry

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Energy and Power Engineering 2012年第3期4卷 132-136页

作者： jack Hardisty The Department of Geography the University of Hull University of Hull Hull UK

It is important to understand the relationship between the ambient ebb and flood currents and the electricity generated by tidal stream power generators to minimise investment risk and to optimise power generation for distribution purposes. Such analyses no longer rely on average descriptions of the flow field or on single values for the device efficiency. In the present paper, we demonstrate a new method involving the integration of synthesised long termflow vectors with logistic descriptions of the device power curves. New experiments are then described with the Neptune Proteus vertical axis tidal stream power generator involving tow tests at speeds to 1.5 ms–1 in william Wright Dock on the Humber. The results are used to derive appropriate coefficients in the logisticcurve and to estimate the device’s annual electrical output.

关键词： Tidal Stream Power Harmonic Tidal Time Series Resource Analysis

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盘县大洞古人类遗址的地层和古气候研究

人类学学报 2003年第2期22卷 131-138页

作者：王頠刘军侯亚梅 Lynne A.Shepartz Sari Miller-Antonio william jack Rink 斯信强黄慰文广西自然博物馆南宁530012 贵州省六盘水市文管所六盘水553001 中国科学院古脊椎动物与古人类研究所北京100044 DepartmentofAnthropology DepartmentofAnthropology CaliforniaStateUniversity SchoolofGeographyandGeology McMasterUniversity 贵州省六盘水市地方志编纂委员会六盘水553001

贵州盘县大洞的堆积物 ,自上而下可以分为 3层。大洞主体堆积物为角砾堆积 ,来源于洞顶灰岩的崩塌 ,另外有人类遗物以及洞外片流作用带入的泥砂。人类化石、旧石器和哺乳动物化石主要分布在第 2层角砾堆积中。堆积物在洞厅各部位均有相... 详细信息

贵州盘县大洞的堆积物 ,自上而下可以分为 3层。大洞主体堆积物为角砾堆积 ,来源于洞顶灰岩的崩塌 ,另外有人类遗物以及洞外片流作用带入的泥砂。人类化石、旧石器和哺乳动物化石主要分布在第 2层角砾堆积中。堆积物在洞厅各部位均有相应分布 ,属同一沉积序列。已知的早期人类活动时间大约从2 60ka .B .P .开始 ,到 142ka .B .P .前后结束 ,对应于深海氧同位素的第 6、7阶段。角砾层下段 ,发育一套遭强烈溶蚀和风化的堆积物 ,地球化学分析结果显示其湿热的沉积环境 ,时间大约在 2 60— 180kaB .P .期间 ,对应于深海氧同位素第 7阶段 ;大洞堆积物在气候变化周期上与黄土。

关键词：堆积物古气候环境氧同位素阶段盘县大洞人类遗址地层

Engineering circuit analysis / 6th ed.

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Engineering circuit analysis /