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971.
Maguen Shira; Vogt Dawne S.; King Lynda A.; King Daniel W.; Litz Brett T.; Knight Sara J.; Marmar Charles R. 《Canadian Metallurgical Quarterly》2011,3(1):21
This study examined the impact of killing on posttraumatic stress symptomatology (PTSS), depression, and alcohol use among 317 U.S. Gulf War veterans. Participants were obtained via a national registry of Gulf War veterans and were mailed a survey assessing deployment experiences and postdeployment mental health. Overall, 11% of veterans reported killing during their deployment. Those who reported killing were more likely to be younger and male than those who did not kill. After controlling for perceived danger, exposure to death and dying, and witnessing killing of fellow soldiers, killing was a significant predictor of PTSS, frequency and quantity of alcohol use, and problem alcohol use. Military personnel returning from modern deployments are at risk of adverse mental health symptoms related to killing in war. Postdeployment mental health assessment and treatment should address reactions to killing in order to optimize readjustment. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
972.
This study first compares two theoretical perspectives on the links between beneficial and detrimental posttraumatic responses. One group of studies claims that positive posttraumatic responses tend to be positively related with negative stress-related responses. Others posit that, after a severe stress, these responses are negatively correlated with each other. We argue that these contradictory results represent the different theoretical positions on the nature of favorable postwar outcomes. A second issue investigated is the associations of beneficial and detrimental postwar responses with demographic variables as well as with exposure to the stress of war. An Israeli adult sample (n = 870) was administered two different measures of negative posttraumatic outcomes (resource loss and postwar symptoms) and two different measures of positive posttraumatic outcomes (resource gains and posttraumatic recovery) one year after they were badly affected by a war. Resource gains correlated positively with resource loss, whereas PTR correlated negatively with postwar symptoms. There were also positive associations between the two measures of stress as well as the two beneficial posttraumatic outcomes. Older age, being a woman, lower economic status, and higher exposure to traumatic events tended to correlate positively with both measures of detrimental outcomes. These variables correlated negatively with PTR, and three of them (excluding economic status) were not significantly linked with resource gains. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
973.
According to the experimental data of the orifice discharge coefficient for the flow through a vertical sharp-edged orifice obtained in the previous study of this work,a theoretical criterion for flow mechanisms of small orifice(viz.thick-walled orifice and nozzle) and large orifice(viz.thin-walled orifice) was proposed based on the ratio of orifice diameter to plate thickness.It can help explain the dissipation of the mechanical energy loss in the flow process for the two flow mechanisms under different operating regimes.The main parameters such as orifice diameter,plate thickness and liquid head were correlated,and a semi-empirical model for orifice coefficient and an empirical model with high precision at the stable region were developed. 相似文献
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利用滚压法使活塞座封油槽的表面粗糙度达到Ra0.8以上,增大了封油槽铸造组织密度,提高了活塞座封油槽表面耐磨性,降低了维修成本,延长整机的使用寿命,提高了整机性能。 相似文献
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XD系列全液压动力头岩心钻机的研制和应用 总被引:6,自引:2,他引:4
王繁荣 《探矿工程(岩土钻掘工程)》2011,38(12):43-46
简要概述了全液压动力头岩心钻机目前的发展状况,分析了XD系列全液压动力头岩心钻机的特点、结构组成、性能参数以及钻机的应用情况。 相似文献
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