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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   
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The first objective of this paper investigates the influence of the previous strain history on ratcheting. New tests were performed where different strain-controlled histories have been applied prior to ratcheting tests. It is demonstrated that under the same conditions, one can observe ratcheting, plastic shakedown or elasticity according to the prior strain-controlled history. The second objective points out the correlation between the experimental data base devoted to the identification of the material parameters and the quality of the predictions in cyclic plasticity. The results suggest that the choice of the tests should be closely linked to the capabilities of the model. In particular, the presence of non proportional strain-controlled tests in the data base may be not a good choice if the model itself is not able to represent explicitly such a character. All tests considered here were performed on 304L SS at room temperature.  相似文献   
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Although the round goby, Neogobius melanostomus, is widespread in the Great Lakes and has an extended breeding season with a high reproductive rate; its spawning behaviour remains elusive. We present the first reported accounts of spawning by the round goby in the laboratory. By simulating winter conditions and restoring spring conditions, we induced round gobies to spawn in October 2007, March 2008, May 2008, and January 2009. In one case, fanning by the nest-holding male began 10 days before egg deposition and, during this period, the male rubbed secretions along the ceiling of the nest. Males were choosy about which gravid females entered the nest and prevented entry by some females. Spawning involved repeated inversions by females and males releasing gametes on the ceiling of the nest. Males guarded the nest by blocking the entrance, producing agonistic vocalizations and chasing intruders. Inside the nest, eggs were regularly inspected by the males and constantly ventilated using pectoral and caudal fins. Up to three gravid females spawned sequentially in a nest. Peak ventilation occurred after egg deposition and declined with time until the parental male ate the eggs. The decline of parental care and egg cannibalism was likely an artifact of laboratory conditions and small brood size. Our findings offer new information on the reproductive habits of the invasive round goby. Because the reproductive sequence in the laboratory seems easy to disrupt, the procedures may lead to a management tool to control the spread of the species into new areas.  相似文献   
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Melt‐state and solid state mechanical properties and thermal stability of polylactide layered silicate nanocomposites elaborated by melt intercalation were studied as a function of clay content. Wide angle X‐ray scattering results, transmission electron microscopy observations, and rheological measurements indicated that the clay was finely distributed in the polylactide matrix. Contrary to nonlinear mechanical properties, thermal and linear mechanical properties were shown to increase with increasing clay fraction. The nanoindentation measurements confirm the significant increase of linear mechanical properties previously observed by tensile tests. The good correlation of linear mechanical properties at the macrometric and nanometric scales is explained by the high dispersion degree of the nanofiller in the biodegradable polymer matrix. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   
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Evaluated the effectiveness of human immunodeficiency virus (HIV) testing and counseling among homosexual and bisexual men participating in the San Francisco City Clinic Cohort (Centers for Disease Control, 1987). Behavioral data from 181 men who learned their HIV antibody status between 1985 and 1987 were compared with data from 128 men who were tested but declined to receive their results. Significant declines in risk indices for unprotected receptive and insertive anal intercourse occurred between 1983–1984 and 1986–1987, but these declines were independent of both knowledge of HIV status and actual serostatus. Ss who chose to learn their HIV status were no more likely to report depression or anxiety subsequent to testing. Frequent access to and discussion of risk-reduction information may be important motivators of behavioral change. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Burrowing mayfly species of the genus Hexagenia are well known indicators of environmental health in lakes and rivers. Two species, H. limbata and H. rigida, are indistinguishable as nymphs and as adult females. Our objectives were to develop a genetic technique to distinguish between the two species and identify morphological features that separate cryptic nymphs and adult females. Fifty nymphs were collected before emergence from 10 sites throughout the western basin of Lake Erie in 2004 and 2005. Using known specimens of adult aerial male H. limbata and H. rigida, we used the mitochondrial cytochrome c oxidase subunit 1 (COI) gene to identify a 16 base pair (bp) difference between species. DNA sequencing confirmed correct species identification based on differences in abdominal pigmentation patterns on adult female imagos in 19 of 20 cases; the lone exception was a female with very faint pigmentation. Pigmentation patterns between species were consistent on nymphs, subimagos and imagos of both sexes. Populations of both species are panmictic across the western basin of Lake Erie, but H. limbata is the numerically dominant species, representing 70 to 100% of nymphs at sites in both years. A separate lineage of H limbata was discovered in the samples. The ability to distinguish nymphs of the two species will aid in developing more sensitive ecosystem indicators.  相似文献   
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A review of articles in Psychological Assessment reveals that many researchers develop instruments without the benefit of consultation with members of the target population. To the extent that researchers do consult the target population, most fail to bring consultation in early enough to inform the identification and specification of key constructs. Moreover, this consultation typically takes the form of one-to-one interviews. The authors' goal in this article was to elaborate on the importance of population consultation as part of content validation and to critically evaluate the potential of one method of consultation, focus groups, to inform multiple stages of instrument development. The authors suggest that this method holds promise for enhancing the content validity of instruments and, ultimately, the validity of research findings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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