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301.
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   
302.
Mean residual life is a useful dynamic characteristic to study reliability of a system. It has been widely considered in the literature not only for single unit systems but also for coherent systems. This article is concerned with the study of mean residual life for a coherent system that consists of multiple types of dependent components. In particular, the survival signature based generalized mixture representation is obtained for the survival function of a coherent system and it is used to evaluate the mean residual life function. Furthermore, two mean residual life functions under different conditional events on components’ lifetimes are also defined and studied.  相似文献   
303.
We study new decision and optimization problems of finding a simple path between two given vertices in an arc weighted directed multigraph such that the path length is equal to a given number or it does not fall into the given forbidden intervals (gaps). A fairly complete computational complexity classification is provided and exact and approximation algorithms are suggested.  相似文献   
304.
It is well‐known that the efficient set of a multiobjective linear programming (MOLP) problem can be represented as a union of the maximal efficient faces of the feasible region. In this paper, we propose a method for finding all maximal efficient faces for an MOLP. The new method is based on a condition that all efficient vertices (short for the efficient extreme points and rays) for the MOLP have been found and it relies on the adjacency, affine independence and convexity results of efficient sets. The method uses a local top‐down search strategy to determine maximal efficient faces incident to every efficient vertex for finding maximal efficient faces of an MOLP problem. To our knowledge, the proposed method is the first top‐down search method that uses the adjacency property of the efficient set to find all maximal efficient faces. We discuss this and other advantages and disadvantages of the algorithm. We also discuss some computational experience we have had with our computer code for implementing the algorithm. This computational experience involved solving several MOLP problems with the code.  相似文献   
305.
ABSTRACT

From 1944 to 1973 Australia attempted to acquire atomic weaponry. This ambition was driven by the desire to contribute to defending British interests in Asia, fears of invasion by China, Indonesia, and Japan, great-power war, and the belief that nuclear weapons were merely bigger and better conventional weapons, that they would proliferate, and that US security assurances lacked credibility. Although the pursuit of the bomb was eventually abandoned, this was not the result of US assurances. Rather, geopolitical changes in Australia’s environment meant that a major attack on the continent was unlikely to occur outside the context of a confrontation between the US, China, and the Soviet Union. This article argues that Australia may soon have to rethink its policies towards US extended deterrence and instead focus on developing its own deterrent.  相似文献   
306.
The role of norms and military utility in the use of weapons is disputed by constructivist and realist scholars. Through an examination of US decision-making regarding anti-plant and irritant agents in the Vietnam War, I advance this debate in three key ways. First, I develop structural realism’s expectations regarding the role of military utility. Second, I demonstrate that social and material factors are at play in our understandings of both ‘norms’ and ‘military utility’, and that both played a role in US decisions. Third, I find that the dominant role – as structural realism expects – was played by military utility.  相似文献   
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309.
Particularly in African operations, United Nations (UN) peacekeeping forces have faced significant problems in restoring stability. In at least a few situations, unilateral national military interventions have been launched in the same countries. In the cases of Sierra Leone and Côte d’Ivoire, the British and French interventions respectively played a significant role in re-establishing stability. Lessons from these operations suggest that if effective coordination and liaison channels are established, such hybrid unilateral-UN missions can in fact be more successful than “pure” peace operations.  相似文献   
310.
In recent years, there has been a sharp growth in political and sociological interest in the British military. Set against the backdrop of the armed forces’ increasing presence in everyday life, alongside the organizations’ ongoing restructuring, the current paper focuses on the MoD’s problematic attempts to recruit 30,000 reservists by 2020; what has become known as the Future Reserves 2020 programme (FR2020). We argue that these changes are driven in part by the need to cut costs in defence. However, we also suggest that they are a reflection of the changing nature of modern military organisation, and the manner in which armed forces engage with the societies of which they are a part, and with the citizens that make up that society. We locate FR2020 programme in the context of a wider narrative about the changing nature of military organisation in contemporary western democracies, identifying structural, circumstantial and normative reasons for change. We also examine the specific challenges of implementing FR2020 in practice, including issues of recruitment and retention, integration and support, and relations with families and employers, drawing on the experience of comparator countries to do so. We conclude by considering the implications of these changes, both for the future of UK armed forces, and for the evolving nature of military-society relations in Britain.  相似文献   
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