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21.
Optimal cognitive ability is likely important for military working dogs (MWD) trained to detect explosives. An assessment of a dog’s ability to rapidly learn discriminations might be useful in the MWD selection process. In this study, visual discrimination and reversal tasks were used to assess cognitive performance in Labrador retrievers selected for an explosives detection program using a modified version of the Toronto General Testing Apparatus (TGTA), a system developed for assessing performance in a battery of neuropsychological tests in canines. The results of the current study revealed that, as previously found with beagles tested using the TGTA, Labrador retrievers (N = 16) readily acquired both tasks and learned the discrimination task significantly faster than the reversal task. The present study confirmed that the modified TGTA system is suitable for cognitive evaluations in Labrador retriever MWDs and can be used to further explore effects of sex, phenotype, age, and other factors in relation to canine cognition and learning, and may provide an additional screening tool for MWD selection.  相似文献   
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African American women at increased risk of HIV/sexually transmitted infection (STI) may engage in risky sex as a coping mechanism for depressed economic conditions. This study examines the association between high-risk sexual behavior and structural determinants of sexual health among a sample of young African American women. 237 young African American women (16–19 years old) from economically disadvantaged neighborhoods in North Carolina were enrolled into a randomized trial testing the efficacy of an adapted HIV/STI prevention intervention. Logistic regression analyses predicted the likelihood that young women reporting lack of food at home, homelessness and low future prospects would also report sexual risk behaviors. Young women reporting a lack of food at home (22 %), homelessness (27 %), and low perceived education/employment prospects (19 %) had between 2.2 and 4.7 times the odds as those not reporting these risk factors of reporting multiple sex partners, risky sex partners including older men and partners involved in gangs, substance use prior to sex, and exchange sex. Self-reported structural determinants of sexual health were associated with myriad sexual risk behaviors. Diminished economic conditions among these young women may lead to sexual risk due to hopelessness, the need for survival or other factors.  相似文献   
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John D. Norton 《Synthese》2014,191(4):671-690
In a formal theory of induction, inductive inferences are licensed by universal schemas. In a material theory of induction, inductive inferences are licensed by facts. With this change in the conception of the nature of induction, I argue that the celebrated “problem of induction” can no longer be set up and is thereby dissolved. Attempts to recreate the problem in the material theory of induction fail. They require relations of inductive support to conform to an unsustainable, hierarchical empiricism.  相似文献   
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The study investigated the moderating role of occupational self-efficacy and job social support on the relationship between job demands and psychological well-being among mid-career academics. Participants were 203 academics at three public Nigerian universities (female = 37.93%; mean years of service = 8.58 years, SD = 2.20). The academics completed measures of job demands, occupational self-efficacy, job social support, and psychological well-being. Moderated regression analysis of the data suggested only occupational self-efficacy to moderate the relationship between work demands and psychological well-being. Findings underpin the buffering effects of work self-efficacy in employee psychological well-being with high job demands.  相似文献   
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Research on the correlates of maternal employment has yielded inconsistent results. In this study, 79 male and 120 female undergraduates with mothers who had been employed from the students' infancy through their adolescence scored higher on the Beck Depression Inventory-II than those whose mothers had not been employed. This relationship between children's depressive symptoms and mothers' employment history was not evident among young adults whose mothers' employment was perceived to be financially unnecessary.  相似文献   
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