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81.
Since the post-World War II genesis of nuclear deterrence, two presidential initiatives have been presented to deliver humanity from the threat of its failure. The first was the Strategic Defense Initiative (SDI), a constellation of space- and ground-based systems that President Ronald Reagan envisioned would render nuclear weapons “impotent and obsolete.” The second is President Barack Obama's roadmap to “a world without nuclear weapons,” commonly referred to as “Global Zero.” While these proposals appear to have little in common, deeper investigation reveals a number of provocative similarities in motivation and presentation. Moreover, both generated fierce debate, often with ideological overtones, about their strategic desirability and technical feasibility. We use these parallels, as well as prominent dissimilarities, to draw lessons from the SDI experience that can be applied to the debate over Global Zero.  相似文献   
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Private military and security companies (PMSCs) play an increasingly important role in the provision of security-related services. In their attempts to win new clients and find suitable personnel, they take on different identities by presenting themselves as conventional businesses, military actors, and humanitarians. In this article, we examine how PMSCs deploy these identities when they recruit new personnel through social media. Our computer-assisted content analysis of Twitter messages posted by two major United States-based companies—CACI and DynCorp International—shows that while both PMSCs amplify their business and military identities to attract the most talented personnel, they construct and communicate these identities in different ways with CACI branding itself as a sophisticated, modern, and patriotic business and DynCorp as a home-grown, traditional military provider. In addition, our analysis lends force to scholars suggesting that state militaries and the private security sector compete increasingly for prospective employees using similar strategies.  相似文献   
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Abstract

Insomnia is prevalent among Veterans with post-traumatic stress disorder (PTSD), it exacerbates PTSD symptoms, and it contributes to impaired functioning and quality of life. To improve treatment outcomes, it is important to identify risk factors for insomnia and sedative-hypnotic use. Classification and regression trees and logistic regression models were used to identify variables associated with insomnia or sedative-hypnotic use. Key findings include low insomnia diagnosis rates (3.5–5.6%) and high rates of sedative-hypnotics (44.2–49.0%). Younger Veterans and those without a breathing-related sleep disorder (BRSD) were more likely to receive an insomnia diagnosis. Veterans with greater service connection and those with an alcohol/substance use disorder were more likely to be prescribed sedative-hypnotics. Interaction terms may have identified potential groups at risk of being under-diagnosed with insomnia (i.e. non-black Veterans with psychiatric co-morbidity, black Veterans without psychiatric co-morbidity) as well as groups at risk for sedative-hypnotic use (i.e. younger Veterans without BRSD). In sum, Veterans with PTSD have high rates of sedative-hypnotic use despite minimal evidence they are effective. This is counter to recommendations indicating behavioral interventions are the first-line treatment. Policy changes are needed to reduce use of sedative-hypnotics and increase access to behavioral insomnia interventions.  相似文献   
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This article provides formulas for estimating the parameters to be used in the basic EOQ lot-size model. The analysis assumes that the true values of these parameters are unknown over known ranges and perhaps nonstationary over time. Two measures of estimator “goodness” are derived from EOQ sensitivity analysis. Formulas are given for computing the minimax choice and the minimum expected value choice for the parameter estimates using both measures of estimator “goodness”. A numerical example is included.  相似文献   
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