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吸入麻醉药的制动效应是否需要一种新的解释

麻醉与镇痛 2010年第3期6卷 61-78页

作者： Edmond I Eger II, MD douglas E. raines, MD Steven L. Sharer, MD Hugh C. Hemmings, Jr., MD, PhD James M. Sonner, MD 张益(译) 喻田(校) Department of Anesthesia and Perioperative Care University of California San Francisco California Department of Anesthesia and Critical Care Massachusetts General Hospital and Harvard Medical School Boston Massachusetts Department of Anesthesia Columbia University New York City New York Departments of Anesthesiology and Pharmacology Weill Cornell Medical College New York City New York 不详

吸入麻醉药使人或动物对伤害性刺激不产生体动反应的具体机制，目前的研究仍然众说纷纭。一些研究发现，如吸入麻醉药之间的相加作用，提示各种麻醉药可能通过作用于一些共同的位点产生制动作用。然而，近20年来的研究却并未真正发现一... 详细信息

吸入麻醉药使人或动物对伤害性刺激不产生体动反应的具体机制，目前的研究仍然众说纷纭。一些研究发现，如吸入麻醉药之间的相加作用，提示各种麻醉药可能通过作用于一些共同的位点产生制动作用。然而，近20年来的研究却并未真正发现一种配体或是电压门控通道能单独介导这种制动作用。很多猜测的靶点，如阿片受体、5-HT3受体、GABA。受体、谷氨酸受体，以及钾和钙通道等，有的在制动效应的机制中仅起很小的作用，有的则完全没有作用。此外，多种配体门控通道或多种电压门控通道的联合效应也达不到这样的效果。少数较可信的靶点（如钠通道）值得进一步研究，但仍存在非特异性机制的可能。

关键词：吸入麻醉药制动作用 5-HT3受体电压门控阿片受体伤害性刺激谷氨酸受体特异性机制

吸入麻醉药在大鼠最小肺泡有效浓度上无协同作用

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麻醉与镇痛 2010年第1期6卷 1-8页

作者： Edmond I Eger II Michael Tang Mark Liao Michael J. Laster Ken Solt Pamela Flood Andrew lenkins douglas raines Jan F. Hendrickx Steven L. Shafer Tanifuji Yasumasa James M. Sonner 杨静(译) 米卫东(校) Department of Anesthesia and Perioperative Care University of California San Frandsco California Deparmlent of Anesthesia and Critical Care Massachusetts General Hospital Boston Massachusetts Department of Anaesthesia Harvard Medical School Boston Massachusetts Department of Anesthesiology Columbia University New York City New York Department of Anesthesiology Emory University Manta Georgia Department of Anesthesia Stanford University Stanford California Department of Biopharrnaceutical Science UCSF San Francisco California Tokyo Japan Department of Anesthesiology Jekei University School of Medicine Tokyo Japan 不详

背景本研究假设对特定受体或通道具有不同作用强度[一种在最小肺泡麻醉药浓度（MAC）时作用弱，另一种则作用较强]的两个吸入麻醉药联合使用时可产生协同作用.这种非单纯相加的相互作用方式将支持麻醉药是通过多位点作用而产生麻醉效应... 详细信息

背景本研究假设对特定受体或通道具有不同作用强度[一种在最小肺泡麻醉药浓度（MAC）时作用弱，另一种则作用较强]的两个吸入麻醉药联合使用时可产生协同作用.这种非单纯相加的相互作用方式将支持麻醉药是通过多位点作用而产生麻醉效应的论点。方法根据药物作用强度差别（一个作用弱，一个作用强），我们研究了11组相加为1MAC的麻醉药物对某特定受体或通道的作用.此处“作用强度差别”是指两种麻醉药在体外对特定受体或通道的增强或阻断作用，按MAC计算，作用较强者至少是较弱者的两倍（或更多）。这些特定受体包括：TREK-1和TASK-3钾通道；γ-氨基丁酸A（GABAA）、甘氡酸、N-甲基-D-天门冬氡酸和乙酰胆碱受体。我们还研究了环丙烷-苯酚组合，因为N-甲基-D-天门冬氨酸受体阻滞剂MK-801对这两种药物MAC的影响明显不同。此外，纳入研究的还有4对包含氧化亚氯的组合，因为有报道氧化亚氮与异氟烷联合应用可产生亚相加作用（拮抗作用）。结果除氧化亚氮和异氟烷组合产生了拮抗作用之外，其余所有组合的作用强度均在所预计两者之和10％的范围以内．结论本研究结果支持“吸入麻醉药是作用于单一位点而抑制伤害刺激所致体动反应”的观点。

关键词：吸入麻醉药肺泡有效浓度 N-甲基-D-天门冬氨酸受体阻滞剂协同作用乙酰胆碱受体 γ-氨基丁酸天门冬氡酸大鼠

Forests,atmospheric water and an uncertain future: the new biology of the global water cycle

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Forest Ecosystems 2018年第3期5卷 236-257页

作者： douglas Sheil Faculty of Environmental Sciences and Natural Resource Management(MINA) Norwegian University of Life Sciences (NMBU)

Theory and evidence indicate that trees and other vegetation influence the atmospheric water-cycle in various *** influences are more important, more complex, and more poorly characterised than is widely *** there is little doubt that changes in tree cover will impact the water-cycle, the wider consequences remain difficult to predict as the underlying relationships and processes remain poorly characterised. Nonetheless, as forests are vulnerable to human activities, these linked aspects of the water-cycle are also at risk and the potential consequences of large scale forest loss are severe. Here, for non-specialist readers, I review our knowledge of the links between vegetation-cover and climate with a focus on forests and rain(precipitation). I highlight advances, uncertainties and research opportunities. There are significant shortcomings in our understanding of the atmospheric hydrological cycle and of its representation in climate models. A better understanding of the role of vegetation and tree-cover wil reduce some of these shortcomings. I outline and il ustrate various research themes where these advances may be *** themes include the biology of evaporation, aerosols and atmospheric motion, as well as the processes that determine monsoons and diurnal precipitation cycles. A novel theory—the ‘biotic pump’—suggests that evaporation and condensation can exert a major influence over atmospheric dynamics. This theory explains how high rainfall can be maintained within those continental land-masses that are sufficiently forested. Feedbacks within many of these processes can result in non-linear behaviours and the potential for dramatic changes as a result of forest loss(or gain): for example, switching from a wet to a dry local climate(or visa-versa). Much remains unknown and multiple research disciplines are needed to address this: forest scientists and other biologists have a major role to *** ideas, methods and data offer opportun

关键词： Biotic pump Climate Condensation Evaporation Ice-nucleation Transpiration GCM Vapour Water-cycle

Materials and technology of Chinese jades dating to the Western Zhou period (1050―771 BCE)

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Science China(Technological Sciences) 2008年第4期51卷 467-480页

作者： Janet G douglas Department of Conservation and Scientific Research Freer Gallery of Art / Arthur M. Sackler Gallery Smithsonian Institution

Excavated jades dating to the Western Zhou period (1050―771 BCE) from the Xi’an area in Shaanxi Province, China, and contemporaneous jades in the collections of the Arthur M. Sackler Gallery at the Smithsonian Institution have been studied to learn about the jade and stone materials and how they were worked during the Western Zhou period. Materials identification was carried out using a combination of techniques such as Fourier-transform infrared spectroscopy and X-ray diffraction. Tool marks were studied using stereomicroscopy and examination of mold impressions using scanning electron microscopy. All of these objects were pro- duced through simple processes involving solid drilling, riffling, and sharp point abrasion; and no evidence was found for the use of rotary tools for incising or sawing.

关键词： jade nephrite stone China Western Zhou scanning electron microscopy materials technology tool marks

Interpreting forest diversity-productivity relationships:volume values,disturbance histories and alternative inferences

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Forest Ecosystems 2020年第1期7卷 64-75页

作者： douglas Sheil Frans Bongers Faculty of Environmental Sciences and Natural Resource Management(MINA) Norwegian University of Life Sciences(NMBU)Box 50031432 AsNorway Forest Ecology and Forest Management Group Wageningen University&ResearchPO Box 476700 AA WageningenThe Netherlands

Understanding the relationship between stand-level tree diversity and productivity has the potential to inform the science and management of *** shows that plant diversity-productivity relationships are challenging to interpret—and this remains true for the study of forests using non-experimental field *** we highlight pitfalls regarding the analyses and interpretation of such *** examine three themes:1)the nature and measurement of ecological productivity and related values;2)the role of stand history and disturbance in explaining forest characteristics;and 3)the interpretation of any *** show that volume production and true productivity are distinct,and neither is a demonstrated proxy for economic *** stand characteristics,including diversity,volume growth and productivity,vary intrinsically with succession and stand *** should be characterising these relationships rather than ignoring or eliminating *** to do so may lead to misleading *** illustrate,we examine the study which prompted our concerns—Liang et al.(Science 354:aaf8957,2016)—which developed a sophisticated global analysis to infer a worldwide positive effect of biodiversity(tree species richness)on“forest productivity”(stand level wood volume production).Existing data should be able to address many of our *** evaluations will improve understanding.

关键词： Causation Correlation Diversity Inference Productivity Richness Tree-growth Wood-density

The Effect of Natural Hazard Damage on Manufacturing Value Added and the Impact of Spatiotemporal Data Variations on the Results

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International Journal of Disaster Risk Science 2022年第5期13卷 691-704页

作者： douglas Thomas Jennifer Helgeson National Institute of Standards and Technology GaithersburgMD 20899USA

This study examined the effect of natural hazards on manufacturing industry value added and the sensitivity of the results from changes to spatiotemporal resolution of the *** measured the negative effects of hazards,rather than the net *** models were developed with varying spatio temporal units for the continental United States:annual/county units;annual/state units;and quarterly/state *** simulations were run using each model to estimate the negative effect of damage from all natural hazards on value added across spatiotemporal ***,an investment analysis was conducted to examine the return from public investments in hazard *** results do not demonstrate that,locally,natural hazards reduce value ***,the evidence suggests that natural hazards in the upstream supply chain have statistically significant impact when modeled at the annual/county scale and at the quarterly/state *** local nor supply chain hazards have a statistically significant effect when modeled at the annual/state scale,suggesting that broader spatiotemporal units may obscure the true downstream effects of natural *** investment analysis,utilizing model results,suggests that an investment of USD 100 billion or less is economical if it results in a reduction in losses of 10% or more.

关键词： Manufacturing Natural hazards Spatiotemporal impacts United States Value added

Slab and Level 2 Automation Design Guidelines for Optimum Metallurgy and Productivity for Plate and Steckel Mills

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Journal of Iron and Steel Research International 2011年第S1期18卷 550-556页

作者： Stalheim douglas DGS Metallurgical Solutions Inc. 15003 NE 10th StreetVancouverWA 98684 USA

Many new steel plate processing facilities have been built in the past 10 years around the world with many more being planned for the *** is especially true in developing countries such as China,India and *** of these facilities are plate mills with either one or two stands or a Steckel mill,typically only one stand designed for the production of structural plate ***,there is a lack of understanding with both the mill builders of the world and the mill owners on the importance of properly matching up the available slab supply (either new as part of a new plate/Steckel mill complex or part of an already existing) with the desired end plate product *** mill builders and owners around the world believe that you can take any slab of any dimension and make any plate dimension you *** this is basically true with today’s Level 2 automation systems,it does not always result in optimum metallurgy/mechanical properties or *** less than optimum condition results in mechanical property failures,shape issues,productivity losses and in general a less than desirable costly processing *** is important to the overall optimization of a steel processing facility that the proper slab dimensions be used to produce the proper final plate dimensions along with achieving the required mechanical *** critical nature of this selection will be dependent on the final plate thickness and overall mechanical property *** mechanical property,shape and overall microstructure are heavily dependent on the ability to properly work the entire cross section of the slab through the rolling *** mechanical property,shape and microstructural issues are a result of improper working of the entire cross section during *** ability for a given mill to properly work the entire cross section is dependent on proper slab selection (total reduction ratio) and a proper rolling schedule either generated manual

关键词： slab dimensions optimization grain size rolling schedule automation Level 2

Metallurgical Optimization of Microalloyed Steels for Oil and Gas Transmission Pipelines

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Journal of Iron and Steel Research International 2011年第S1期18卷 669-674页

作者： Stalheim douglas DGS Metallurgical Solutions Inc. 15003 NE 10th StreetVancouverWA98684 USA

The production of microalloyed steels for oil and gas transmission pipelines has increased significantly over the past *** more and more countries developing their own capabilities to produce pipeline steels to support their own internal pipeline infrastructure development,there has been an increase of steel producers working to develop their own capabilities to produce microalloyed steels for this ***,to achieve the desired mechanical property attributes for transmission pipeline applications utilizing a cost effective approach requires metallurgical optimization of the microalloyed *** achieve metallurgical optimization a basic understanding is required in the design of a cost effective alloy and then the proper processing of that alloy design to achieve the optimum microstructure/mechanical *** this sense,many producers in the world,especially those who have only recently,in the past 10 years,developed their capability to produce microalloyed transmission pipeline steels still do not achieve metallurgical optimization of their alloy and *** results in yield losses due to failures,inefficient processing causing productivity losses and additional expensive additions of alloys to compensate for failures and process *** the supplier of plate/coil has the largest percentage effect on the final cost of the pipe,the steel producer must understand proper alloy,microstructure,and process design to produce a uniform and stable plate/coil to be used in pipe *** means that strength,toughness and microstructure must be uniform down the length,across the width and through the cross *** optimization is achieved when this uniformity is achieved with a cost effective *** to that,non-uniformity results in pipe forming,welding,expansion,mechanical property and production issues resulting in downgraded pipe and cost overruns in *** paper will describe targets for p

关键词： microalloy niobium pipeline solubility grain size rolling schedule

50 years change in urban land use and ecological planning globally in the era of design with nature

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Ecosystem Health and Sustainability 2019年第1期5卷 185-198,I0001页

作者： Ian douglas School of Environment Education and DevelopmentUniversity of ManchesterManchesterUK

Ian McHarg’s 1969 book,Design with Nature,was grounded in earlier good practice,especially the European vision of fitting cities into the regional landscape and carrying thorough surveys before planning *** book emerged in the wake of publications that worried about the ability of the earth to support expanding populations and their growing impact on the *** argued that ecological design should follow planning based on detailed site *** McHarg advised many urban authorities in the USA and other countries,especially in Africa,Asia and Europe,and his ideas had influenced some British new towns,they had little attention in the planning of Milton Keynes,England’s largest new urban settlement,where the initial geological surveys were inadequate,but a successful large tree-planting programhas created a“city in the forest.”McHarg was however closely involved in planning the Nigerian Capital city,Abuja,but his sound master plan was ill-equipped to provide for a nation undergoing post-conflict rebuilding and a local population more concerned with access to land than ecological ***,McHarg helped us to promote,protect,and preserve urban green *** teams from different disciplines now work well together,the integrated thinking advocated by McHarg remains sometimes in short supply in local practice.

关键词： Planning design urban nature garden city site investigation