13,229 research outputs found

    Governance of Dual-Use Technologies: Theory and Practice

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    The term dual-use characterizes technologies that can have both military and civilian applications. What is the state of current efforts to control the spread of these powerful technologies—nuclear, biological, cyber—that can simultaneously advance social and economic well-being and also be harnessed for hostile purposes? What have previous efforts to govern, for example, nuclear and biological weapons taught us about the potential for the control of these dual-use technologies? What are the implications for governance when the range of actors who could cause harm with these technologies include not just national governments but also non-state actors like terrorists? These are some of the questions addressed by Governance of Dual-Use Technologies: Theory and Practice, the new publication released today by the Global Nuclear Future Initiative of the American Academy of Arts and Sciences. The publication's editor is Elisa D. Harris, Senior Research Scholar, Center for International Security Studies, University of Maryland School of Public Affairs. Governance of Dual-Use Technologies examines the similarities and differences between the strategies used for the control of nuclear technologies and those proposed for biotechnology and information technology. The publication makes clear the challenges concomitant with dual-use governance. For example, general agreement exists internationally on the need to restrict access to technologies enabling the development of nuclear weapons. However, no similar consensus exists in the bio and information technology domains. The publication also explores the limitations of military measures like deterrence, defense, and reprisal in preventing globally available biological and information technologies from being misused. Some of the other questions explored by the publication include: What types of governance measures for these dual-use technologies have already been adopted? What objectives have those measures sought to achieve? How have the technical characteristics of the technology affected governance prospects? What have been the primary obstacles to effective governance, and what gaps exist in the current governance regime? Are further governance measures feasible? In addition to a preface from Global Nuclear Future Initiative Co-Director Robert Rosner (University of Chicago) and an introduction and conclusion from Elisa Harris, Governance of Dual-Use Technologiesincludes:On the Regulation of Dual-Use Nuclear Technology by James M. Acton (Carnegie Endowment for International Peace)Dual-Use Threats: The Case of Biotechnology by Elisa D. Harris (University of Maryland)Governance of Information Technology and Cyber Weapons by Herbert Lin (Stanford University

    Review of \u3cem\u3eThe Loyal West: Civil War and Reunion in Middle America\u3c/em\u3e by Matthew E. Stanley

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    Interest in Civil War memory and post–Civil War sectional reconciliation has expanded greatly in recent years, as two 2016 historiographical essays attest.1 Matthew E. Stanley\u27s new book, The Loyal West: Civil War and Reunion in Middle America is thus well timed to make an important contribution to our evolving understanding of the process of sectional reconciliation in the decades following the Civil War. With his focus on Kentucky\u27s northern neighbors in the lower portions of Illinois, Indiana, and Ohio, the editorial staff of the Register of the Kentucky Historical Society believe Stanley\u27s book will help historians better understand the role Kentucky played in the events of the late nineteenth and early twentieth century, which saw a white supremacist version of Civil War memory eclipse an emancipationist version nationally. We have asked four nineteenth-century historians to consider Stanley\u27s book from varying perspectives. M. Keith Harris teaches history at a private high school in Los Angeles, California. He is the author of Across the Bloody Chasm: The Culture of Commemoration among Civil War Veterans (2014) and is currently writing a book on D. W. Griffith\u27s controversial 1915 silent film, The Birth of a Nation. Anne E. Marshall is an associate professor of history at Mississippi State University and the author of Creating a Confederate Kentucky: The Lost Cause and Civil War Memory in a Border State (2012). James Marten is professor and chair of the history department at Marquette University. His most recent books are Sing Not War: The Lives of Union and Confederate Veterans in Gilded Age America (2011) and America\u27s Corporal: James Tanner in War and Peace (2014). Kristopher Maulden is a visiting assistant professor of history at Columbia College in Missouri. He is completing a book manuscript on the influence of Federalist politics and federal policy in the Ohio River Valley, and he is engaged in a study of nineteenth-century Ohio newspaper editor Charles Hammond. Finally, the author of The Loyal West, Matthew E. Stanley, assistant professor of history at Albany State University, will respond to the reviews

    Parameters affecting ion intensities in transmission-mode Direct Analysis in Real-Time mass spectrometry

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    A survey of the effect of temperature, transmission module material and analysis time on ion intensities in transmission mode direct analysis in real time mass spectrometry is presented. Ion intensity profiles obtained for two related compounds are similar when analysed separately but are very different when analysed as a mixture

    Advances in Ceramic Matrix Composite Blade Damping Characteristics for Aerospace Turbomachinery Applications

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    For advanced aerospace propulsion systems, development of ceramic matrix composite integrally-bladed turbine disk technology is attractive for a number of reasons. The high strength-to-weight ratio of ceramic composites helps to reduce engine weight and the one-piece construction of a blisk will result in fewer parts count, which should translate into reduced operational costs. One shortcoming with blisk construction, however, is that blisks may be prone to high cycle fatigue due to their structural response to high vibration environments. Use of ceramic composites is expected to provide some internal damping to reduce the vibratory stresses encountered due to unsteady flow loads through the bladed turbine regions. A goal of our research was to characterize the vibration viscous damping behavior of C/SiC composites. The vibration damping properties were measured and calculated. Damping appeared to decrease with an increase in the natural frequency. While the critical damping amount of approximately 2% is required for typical aerospace turbomachinery engines, the C/SiC damping at high frequencies was less than 0.2% from our study. The advanced high-performance aerospace propulsion systems almost certainly will require even more damping than what current vehicles require. A purpose of this paper is to review some work on C/SiC vibration damping by the authors for the NASA CMC turbine blisk development program and address an importance of the further investigation of the blade vibration damping characteristics on candidate CMC materials for the NASA s advanced aerospace turbomachinery engine systems

    Explorations in the Stone-Campbell Traditions: Essays in Honor of Herman A. Norton

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    This important collection of essays honors Herman A. Norton (1921-2002), Dean of the Disciples Divinity House at Vanderbilt University from 1951 until his retirement in 1986. Topics from all three branches of the Stone-Campbell Movement are treated including early leaders like Barton Stone and Alexander Campbell, as well as later studies after the Civil War and into the early 1940s.https://digitalcommons.acu.edu/acu_library_books/1013/thumbnail.jp

    Projected health effects of realistic dietary changes to address freshwater constraints in India : a modelling study

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    Acknowledgements This study forms part of the Sustainable and Healthy Diets in India project supported by the Wellcome Trust's Our Planet, Our Health programme (grant number 103932). LA's PhD is funded by the Leverhulme Centre for Integrative Research on Agriculture and Health. SA is supported by a Wellcome Trust Capacity Strengthening Strategic Award-Extension phase (grant number WT084754/Z/08/A). We would like to thank Zaid Chalabi (London School of Hygiene & Tropical Medicine) for providing valuable guidance on the modelling methods.Peer reviewedPublisher PD

    The impact of fire on habitat use by the short-snouted elephant shrew ('Elephantulus brachyrhynchus') in North West Province, South Africa

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    Several studies have investigated the response of small mammal populations to fire, but few have investigated behavioural responses to habitat modification. In this study we investigated the impact of fire on home range, habitat use and activity patterns of the short-snouted elephant shrew (Elephantulus brachyrhynchus) by radio-tracking individuals before and after a fire event. All animals survived the passage of fire in termite mound refugia. Before the fire, grassland was used more than thickets, but habitat utilization shifted to thickets after fire had removed the grass cover. Thickets were an important refuge both pre- and post-fire, but the proportion of thicket within the home range was greater post-fire. We conclude that fire-induced habitat modification resulted in a restriction of E. brachyrhynchus movements to patches of unburned vegetation. This may be a behavioural response to an increase in predation pressure associated with a reduction in cover, rather than a lack of food. This study highlights the importance of considering the landscape mosaic in fire management and allowing sufficient island patches to remain post-fire ensures the persistence of the small mammal fauna

    Voluntary wheel running augments aortic L-arginine transport and endothelial function in rats with chronic kidney disease

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    Reduced nitric oxide (NO) synthesis contributes to risk for cardiovascular disease in chronic kidney disease (CKD). Vascular uptake of the NO precursor L-arginine (ARG) is attenuated in rodents with CKD, resulting in reduced substrate availability for NO synthesis and impaired vascular function. We tested the effect of 4 wk of voluntary wheel running (RUN) and/or ARG supplementation on endothelium-dependent relaxation (EDR) in rats with CKD. Twelve-week-old male Sprague-Dawley rats underwent 5/6 ablation infarction surgery to induce CKD, or SHAM surgery as a control. Beginning 4 wk following surgery, CKD animals either remained sedentary (SED) or received one of the following interventions: supplemental ARG, RUN, or combined RUN + ARG. Animals were euthanized 8 wk after surgery, and EDR was assessed. EDR was significantly impaired in SED vs. SHAM animals after 8 wk, in response to ACh (10(-9)-10(-5) M) as indicated by a reduced area under the curve (AUC; 44.56 +/- 9.01 vs 100 +/- 4.58, P \u3c 0.05) and reduced maximal response (E-max; 59.9 +/- 9.67 vs. 94.31 +/- 1.27%, P \u3c 0.05). AUC was not improved by ARG treatment but was significantly improved above SED animals in both RUN and RUN + ARG-treated animals. Maximal relaxation was elevated above SED in RUN + ARG animals only. L-[H-3] arginine uptake was impaired in both SED and ARG animals and was improved in RUN and RUN + ARG animals. The results suggest that voluntary wheel running is an effective therapy to improve vascular function in CKD and may be more beneficial when combined with L-arginine

    Cryogenic mechanical loss of a single-crystalline GaP coating layer for precision measurement applications

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    The first direct observations of gravitational waves have been made by the Advanced LIGO detectors. However, the quest to improve the sensitivities of these detectors remains, and epitaxially grown single-crystal coatings show considerable promise as alternatives to the ion-beam sputtered amorphous mirror coatings typically used in these detectors and other such precision optical measurements. The mechanical loss of a 1 μm thick single-crystalline gallium phosphide (GaP) coating, incorporating a buffer layer region necessary for the growth of high quality epitaxial coatings, has been investigated over a broad range of frequencies and with fine temperature resolution. It is shown that at 20 K the mechanical loss of GaP is a factor of 40 less than an undoped tantala film heat-treated to 600 °C and is comparable to the loss of a multilayer GaP/AlGaP coating. This is shown to translate into possible reductions in coating thermal noise of a factor of 2 at 120 K and 5 at 20 K over the current best IBS coatings (alternating stacks of silica and titania-doped tantala). There is also evidence of a thermally activated dissipation process between 50 and 70 K
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