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Neighborhood violence is a persistent source of danger, stress, and other adverse outcomes for urban youth. We examined how 140 African American and Latino adolescents coped with neighborhood danger in low, medium, and high crime neighborhoods throughout Chicago. Participants reported using a range of coping strategies (measured via a modified version of the Ways of Coping Scale; R. S. Lazarus & S. Folkman, 1984). In low and medium crime rate areas, using confrontive strategies was significantly correlated with increased exposure to violence, and no strategies were associated with perceptions of safety. Coping strategies were associated with perceived safety to a substantial degree only in high crime neighborhoods, and none were associated with exposure to violence. A k means cluster analysis identified groups that differed in coping profiles and varied in rates of exposure to violence. Moderating effects of gender, ethnicity, and neighborhood were found for both person level and variable level analyses.  相似文献   
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Use of the mathematical principle of inversion in young children   总被引:2,自引:0,他引:2  
An important issue in the development of mathematical cognition is the extent to which children use and understand fundamental mathematical concepts. We examined whether young children successfully use the principle of inversion and, if so, whether they do so based on qualitative identity, length, or quantity. Twenty-four preschool children and 24 children in Grade 1 were presented with three-term inversion problems (e.g., 3+2-2) and standard problems of similar magnitude (e.g., 2+4-3). Problems were presented in three conditions to determine whether children used inversion at all and, if so, whether their decisions were based on quantitative or nonquantitative features of the problems. Both preschool and Grade 1 children showed evidence of using inversion in a fully quantitative manner, indicating that this principle is available in some form prior to extensive formal instruction in arithmetic.  相似文献   
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The Office of Research Integrity found in 2011 that Vipul Bhrigu, a postdoctoral researcher who sabotaged a colleague’s research materials, was guilty of misconduct. However, I argue that this judgment is ill-considered and sets a problematic precedent for future cases. I first discuss the current federal definition of research misconduct and representative cases of research misconduct. Then, because this case recalls a debate from the 1990s over what the definition of “research misconduct” ought to be, I briefly recapitulate that history and reconsider the Bhrigu case in light of that history and in comparison to other cases involving tampering. Finally, I consider what the aim of a definition of research misconduct ought to be, and argue that the precedent set by the reasoning in this case is problematic.  相似文献   
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The field of nanotechnology and nanoscience is growing rapidly in many areas of research, from electronics to biomedicine to material science. Carbon nanotubes are receiving a lot of attention in the research due to their unique properties and many possible applications. This new material is a good example of how nanotechnology provides us with new opportunities, but at the same time leaves us a lot of unknowns to deal with. In order to deal with the unknowns we need to consider both the science and the ethics of the different applications of this novel material. Nanoethics is the study of the ethical issues in nanotechnology. It is a relatively new field of study and a lot of different methods have been suggested in this area. In this article a method is suggested combining an existing ethical theory with a practical approach in order to do a case study of the ethical considerations of using carbon nanotubes in biomedicine. For the case study to be of practical significance the scientific characteristics and properties of carbon nanotubes are reviewed to give the reader an overview of the research field.  相似文献   
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Adolescents increasingly rely on media for socialization and identity development, and marketing plays a prominent role in this dynamic. Film trailers are one form of advertising that children actively seek out and attend to in their exploration of media. However, little attention has been paid to these advertisements’ gendered narratives and parents’ responses to them. The present study examines parents’ mediation responses to film trailers that promote themes of gender development and are aimed at adolescents. Respondents viewed a trailer that featured either a cisgender or transgender coming-of-age story and responded to cognitive, emotional, and attitudinal survey measures. Results identified both parent and child factors that influence parents’ mediation intentions and support for censorship. Practical implications in parenting, gender development, and marketing are further discussed.  相似文献   
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