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521.
Abstract

The purpose of this study was to analyze the racial and athletic identities of African American male college athletes to determine how the identities might impact the athletic and educational potential and performance of this specific group of college athletes. The study revealed that participants who responded negatively to a poor athletic performance were more likely to have lower levels of academic self-concept. In contrast, college athletes who highly identified with their racial group were more likely to have higher levels of academic self-concept. Overall, the findings reveal the intricacies and complexities of being an African American college student and athlete at predominantly white institutions (PWIs) in the US. As such, the article details the implications of the findings as they relate to African American culture, American sports culture, and higher education realities.  相似文献   
522.
523.
Smart manufacturing systems (SMSs) are envisioned to contain highly automated and IT-driven production systems. To address the complexity that arises in such systems, a standard and holistic model for describing its activities and their interrelationships is needed. This paper introduces a factory design and improvement (FDI) activity model and illustrates a case study of FDI in an electromechanical component factory. In essence, FDI is a reference activity model that encompasses a range of manufacturing system activities for designing and improving a factory during its initial development and also its operational phases. The FDI model shows not only the dependency between activities and manufacturing control levels but also the pieces of information and software functions each activity relies on. We envision that the availability of these pieces of information in digital form to integrate across the software functions will increase the agility of factory design and improvement projects. Therefore, our future work lies in contributing to standards for exchanging such information.  相似文献   
524.
While public libraries are often used by people experiencing homelessness, the value of libraries for homeless children and families has been understudied. This brief explores how public libraries can support families experiencing homelessness and how they can engage with other service providers and agencies as part of a collective impact model to support a wide array of families’ needs. Since homelessness is the result of many interconnected social and economic conditions, this paper also examines how awareness and a lack of knowledge of these factors can impact service delivery and expectations. Finally, a case study of how the Queens Library in New York City engages with family shelters to support children’s learning and exploration is included to provide best practice examples.  相似文献   
525.
The transition to motherhood starts early in pregnancy and is completed when the mother feels competent in caring for the infant. Becoming the mother of a child with disabilities is demanding as their needs are complex. The aim of the review was to appraise completed qualitative and quantitative reports on the challenges of mothers of children with disabilities regarding their own transition to motherhood. A review of the literature was carried out through, first, a computerized search strategy to identify relevant studies from selected databases and, second, quality appraisal and thematic analysis of selected studies. The transition to motherhood of children with disabilities takes place in the inside world at home, the outside world external to home and the ‘going-between’ world of travelling between the two worlds. The mothers are challenged at home to integrate basic infant care with technical care of their children. In the outside world they often struggled to ensure that their children got the necessary professional care. Travelling between their homes and healthcare services posed many problems.  相似文献   
526.
The geographies of the current generation of young people are markedly distinct from previous generations by virtue of their access to a virtual playground. The vast majority of young people now engage in video gaming as a leisure activity. Drawing on findings from the 2009/2010 WHO Health Behaviour in School-aged Children study this paper set out to investigate the factors that might be associated with higher levels of video gaming. Information was collected from 4404 school students aged 11, 13 and 15 years, using anonymised self-completed questionnaires. Higher usage was defined as game play exceeding two hours a day. Separate analyses were conducted for boys and girls. For both genders higher levels of game playing was associated with early adolescence, opposite sex friends and minimal parental mediation. Bullying and going to bed hungry were associated with higher usage for boys only, while life satisfaction and family activities were linked to girls’ game playing only. Parents were identified as effective mediators of young people’s video game usage. The study identified gendered motivations for higher levels of game play, suggesting different interventions for boys and girls may be required in order for young people to create a balanced approach to video gaming.  相似文献   
527.
528.
Species that successfully inhabit urban ecosystems are rare, and urbanisation often drives localised extinctions of native species. Nonetheless, some species take advantage of the novel conditions available in cities and increase in abundance. Trends in the abundance and distribution of species in urban areas have received much attention, but the precise elements of urban ecosystems that affect the survival of urban-dwelling species are largely unknown. Animals that successfully exploit urban environments may do so because of increases in the availability of resources or habitats. Here we assess the effects of anthropogenic landscapes and prey abundance on the persistence of an orb-weaving spider, Nephila plumipes. We assessed spider persistence for six months in situ along an urban gradient in Sydney. We then transplanted spiders from a common garden into sites along the gradient, monitored their persistence in the new environment and measured a suite of environmental variables at local and landscape scales. The abundance of prey was closely linked with spider persistence, in both the survey and the transplant experiment, and was positively associated with anthropogenic habitats. The surveyed spiders survived longer when located closer to the coast and transplanted spiders persisted longer in smaller sites with more impervious surfaces and reduced vegetation cover. Our study shows that urbanisation has a strong effect on potential prey abundance and can lead to increased persistence of N. plumipes, demonstrating the broad impacts that habitat disturbance can have on the life history and trophic interactions of city-dwelling animals.  相似文献   
529.
Both passive and active social influences may affect adolescents' dangerous driving. In this study, we used an experimental paradigm to delineate these two influences with actual peers. Adolescents completed a simulated driving task, and we measured risk preferences of each member of the peer group. We used hierarchical linear modeling to partition variance in risky decisions. Adolescents experienced many more crashes when they had “passengers” present who reported a strong preference for risk taking and who actively provided decision‐making guidance. Although youth in the passive peer condition were also influenced by the riskiness of their peers, this relation was less strong relative to the active condition. We discuss the need for interventions focussing on active and passive peer influence.  相似文献   
530.
Most previous studies of income inequality have either ignored capital gains or have used taxable realized capital gains to estimate top incomes. Neither of these approaches is fully satisfactory. We apply for the first time a new methodology that allows us to account for fundamental accrued capital gains as part of the top incomes in a theoretically consistent manner. We estimate the shares of the super-rich in Chile showing that accrued capital gains have a large impact on these estimates. Also, the top income shares estimated using fundamental capital gains appear to exhibit a more stable and presumably more plausible time profile than estimates based on capital gains derived from asset market variations.  相似文献   
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