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51.
    
Young, rural Black men are disproportionately affected by sexually transmitted infections (STIs), a consequence, in part, of multiple sexual partnerships. We conducted a prospective study that examined the influence of masculinity ideology on changes in numbers of sexual partners in this population. We focused on a set of high-risk attitudes termed reputational masculinity. Community disadvantage during young adulthood was examined as a risk factor for reputational masculinity ideology, and vocational commitment was examined as a potential protective factor. The sample included 505 African American men ages 19 to 22 from high-poverty rural communities. Men reported their numbers of sexual partners during the past three months, masculinity ideology, community disadvantage, and vocational commitment. Follow-up data were collected 18 months after baseline assessment. Negative binomial modeling was used to test study hypotheses. Results indicated that community disadvantage was associated with increases in reputational masculinity during early adulthood, which in turn were linked to increases in numbers of sexual partners. Vocational commitment interacted with reputational masculinity to forecast numbers of sexual partners, attenuating the influence of reputational masculinity. Reputational masculinity and promotion of engagement with the workplace may be important targets for interventions designed to reduce sexual risk behavior.  相似文献   
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There are over 2.5 million custodial grandparents raising 4.8 million grandchildren in the U.S. These grandparents face many major struggles, including increasing financial costs, physical disabilities, and deteriorating home environments. Our study investigates grandchild well-being, particularly the safety of custodial grandparents’ homes and its relation to injury prevention. This is crucial, as unintentional injury is the leading cause of death for children. Our model predicted child safety based on grandparent gender, depressive symptoms, and safety knowledge. Our model fit well and explained 23% of the variance in child injuries. Several gender differences were also present, for both grandparent and grandchild gender.  相似文献   
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Using data from U.S. commodity flow survey, we show that the historical Union–Confederacy border lowers contemporaneous trade between U.S. states by about 13%. The finding is robust over econometric models, survey waves, or aggregation levels. Including contemporaneous controls, such as network or institutional variables, lowers the estimate only slightly. Historical variables, such as slavery, do not explain the effect. Adding U.S. states unaffected by the Civil War, we argue that the friction is not merely reflecting unmeasured North–South differences. Finally, the border effect is larger for differentiated than for homogeneous goods, stressing the potential role for cultural factors and trust. (JEL F15, N72, N92, Z10)  相似文献   
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We explored how academic literature constructs the ‘worker with autism.’ Drawing on a systematic review of transition to work for youth with disabilities, we analyzed how 17 articles constructed ‘autism,’ ‘work,’ and the ‘worker with autism.’ We identified two argumentative approaches: the intervention story and the complex story. Intervention stories centered autism as a problem in need of treatment and work as a simple, positive endeavor. Complex stories offered various and more positive accounts of autism alongside broader notions of work. We recommend that academics experiment with writing which expands work (and career) possibilities for youth situated on the autism spectrum.  相似文献   
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Visible expenditures which convey higher socioeconomic status may help individuals differentiate themselves in the marriage market when there is competition for partners and imperfect information. We examine a unique dataset of automobile purchasers in China to investigate the extent to which skewed sex ratios influence expenditure decisions for this highly visible commodity. Using a triple difference approach, we show that unmarried male consumers who face an unfavorable sex ratio purchase more expensive, luxury vehicles than their married peers. Lower income borrowers and those residing in regions with the worst sex ratios exhibit the largest relative degree of conspicuous consumption. In addition to the direct cost of consumption signaling, we demonstrate that this behavior generates negative externalities in the form of lower average fuel economy and higher average vehicle weight. As it has worsened sex ratios, status competition and the associated negative repercussions we identify represent unintended consequences of China's one child policy. (JEL O12, E21, J12)  相似文献   
56.
This article examines the significance of field education placements within contemporary social work field education, particularly considering the increasingly complex issues of the duty of care (to student, agency and field teacher) and the duty to disclose (to student, to field teacher) which schools of social work must negotiate. The dilemmas facing schools and field educators, and the steps taken to resolve them at the University of Melbourne (Australia), are considered to highlight the ongoing liability and accountability difficulties which continue to face social work education.  相似文献   
57.
    
Sexual development entails many experiences and is a major feature of adolescence. Most relevant behavioral genetic studies, however, focus primarily on sexual behaviors associated with health risks. We took a more normative, developmental perspective by examining genetic and environmental influences on five sexual behaviors ranging from dating to pregnancy in middle (Mage = 14.90 years) and late adolescence (Mage = 17.85 years) in a sample of twins (N = 3,762). Overall, behaviors that are more common and socially sanctioned (e.g., dating) were more heritable than behaviors that are less common and socially acceptable (e.g., sexual intercourse). That the etiology of different sexual behaviors is tied to their normativeness highlights the importance of considering the broader developmental context when studying sexual development.  相似文献   
58.
Conventional optimization approaches, such as Linear Programming, Dynamic Programming and Branch-and-Bound methods are well established for solving relatively simple scheduling problems. Algorithms such as Simulated Annealing, Taboo Search and Genetic Algorithms (GA) have recently been applied to large combinatorial problems. Owing to the complex nature of these problems it is often impossible to search the whole problem space and an optimal solution cannot, therefore, be guaranteed. A BiCriteria Genetic Algorithm (BCGA) has been developed for the scheduling of complex products with multiple resource constraints and deep product structure. This GA identifies and corrects infeasible schedules and takes account of the early supply of components and assemblies, late delivery of final products and capacity utilization. The research has used manufacturing data obtained from a capital goods company. Genetic Algorithms include a number of parameters, including the probabilities of crossover and mutation, the population size and the number of generations. The BCGA scheduling tool provides 16 alternative crossover operations and eight different mutation mechanisms. The overall objective of this study was to develop an efficient design-of-experiments approach to identify genetic algorithm operators and parameters that produce solutions with minimum total cost. The case studies were based upon a complex, computationally intensive scheduling problem that was insoluble using conventional approaches. This paper describes an efficient sequential experimental strategy that enabled this work to be performed within a reasonable time. The first stage was a screening experiment, which had a fractional factorial embedded within a half Latin-square design. The second stage was a half-fraction design with a reduced number of GA operators. The results are compared with previous studies. It is demonstrated that, in this case, improved GA performance was achieved using the experimental strategy proposed. The appropriate genetic operators and parameters may be case specific, leading to the view that experimental design may be the best way to proceed when finding the 'best' combination of GA operators and parameters.  相似文献   
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