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191.
192.
Despite more than thirty years of debate, disagreement persists among research ethicists about the most appropriate way to interpret the U.S. regulations on pediatric research, specifically the categories of “minimal risk” and a “minor increase over minimal risk.” Focusing primarily on the definition of “minimal risk,” we argue in this article that the continued debate about the pediatric risk categories is at least partly because their conceptual status is seldom considered directly. Once this is done, it becomes clear that the most popular strategy for interpreting “minimal risk”—defining it as a specific set of risks—is indefensible and, from a pragmatic perspective, unlikely to resolve disagreement. Primarily this is because judgments about minimal risk are both normative and heavily intuitive in nature and thus cannot easily be captured by reductions to a given set of risks. We suggest instead that a more defensible approach to evaluating risk should incorporate room for reflection and deliberation. This dispositional, deliberative framework can nonetheless accommodate a number of intellectual resources for reducing reliance on sheer intuition and improving the quality of risk evaluations.  相似文献   
193.
Young, gay, and bisexual men (YGBM) are at increased risk of family rejection, which is related to HIV infection. What remains unknown is how family rejection leads to HIV risk. In this exploratory study, qualitative interviews were conducted with 21 HIV-positive YGBM aged 18 to 24. Most participants reported family rejection, which decreased instrumental and emotional support and resulted in participants using riskier ways to support themselves, such as engaging in survival sex. Conceptualizing the findings using a family systems framework, we present a tentative conceptual model to describe the potential relationships between family rejection and HIV risk for YGBM.  相似文献   
194.
Research suggests that high frequency gambling is a component of the “generality of deviance”, which describes the observation that various forms of risky and antisocial behavior tend to co-occur among individuals. Furthermore, risky and antisocial behaviors have been associated with such personality traits as low self-control, and impulsivity, and sensation-seeking. We conducted a replication (and extension) of two previous studies examining whether high frequency gambling is part of the generality of deviance using a large and diverse community sample (n = 328). This study was conducted as a response to calls for more replication studies in the behavioral and psychological sciences (recent systematic efforts suggest that a significant proportion of psychology studies do not replicate). The results of the present study largely replicate those previously found, and in many cases, we observed stronger associations among measures of gambling, risk-taking, and antisocial behavior in this diverse sample. Together, this study provides evidence for the generality of deviance inclusive of gambling (and, some evidence for the replicability of research relating to gambling and individual differences).  相似文献   
195.
Urbanization and other land cover changes have been particularly detrimental to wetlands throughout the planet. One wetland specialist that may be sensitive to land cover changes surrounding wetlands is the round-tailed muskrat (Neofiber alleni; hereafter RTM). The RTM is a wetland obligate rodent that appears to have declined over the last half century and is a species of concern in Florida, where it is a near endemic. To determine if urbanization or other land cover influenced the distribution of RTMs we took a multi-scaled approach to examine the occurrence of RTMs and their associated vegetation in North-Central Florida. We detected RTMs on 19 of 72 sample plots and used a Classification And Regression Tree (CART) to determine that dogfennel (Eupatorium capillifolium) was negatively associated with RTMs and maidencane (Panicum hemitomon) was positively associated with their occurrence on sampling plots. Examining the influence of landscape composition for 2 km surrounding our plots we found that RTM occurrence was negatively related to urban land cover. Further, we found that dogfennel increased and maidencane decreased as urbanization increased in the surrounding landscape. Our research suggests that conservation of RTMs and their associated vegetation should focus on limiting urban sprawl at least within 2 km of wetlands.  相似文献   
196.
The networked age promises global digital cultures with flattened power relations, given the affordances of information and communication technologies to collapse distance, enable easier cross-country collaborations and create new opportunities for knowledge production and sharing. In the academic domains, indications are that knowledge patterns continue to reflect physically based geopolitical realities – where knowledge from the South is still peripheral while knowledge from the North still dominates in terms of all the conventional metrics. This study explores the potential role of digital affordances to challenge structural Northern bias and generates questions about knowledge production and dissemination in the climate change knowledge domain. It is framed by the field of scholarly communication within an African setting and by the emergent field of climate change which is fraught with debates and contestations, particularly regarding mitigation and adaptation. It draws on Southern theory which interrogates the global dynamics of knowledge production and dissemination. It explores the intersection of the discoverability and visibility of local climate change research methodologically from the outside in, through an experiment of searches for ‘climate change/South Africa’ and from the inside out by reviewing the online presence of one climate change group in a top-ranked African university.  相似文献   
197.
ABSTRACT

Forensic evaluation of deaf individuals presents unique challenges due to many examinees’ fund of information deficits, potential for language deprivation, and examiners’ frequent lack of creativity regarding communication methods. This article describes challenges most frequently encountered in competency to stand trial and criminal responsibility evaluations and offers strategies for overcoming them. The value of employing multiple communication methods, especially the use of illustrations, is emphasized. Suggestions also are offered regarding preparing evaluation reports and effectively communicating “key deaf fundamentals” to legal personnel. Encouragement is offered for qualified, sign-fluent professionals to engage in forensic work.  相似文献   
198.
This research was motivated by our goal to design an efficient clinical trial to compare two doses of docosahexaenoic acid supplementation for reducing the rate of earliest preterm births (ePTB) and/or preterm births (PTB). Dichotomizing continuous gestational age (GA) data using a classic binomial distribution will result in a loss of information and reduced power. A distributional approach is an improved strategy to retain statistical power from the continuous distribution. However, appropriate distributions that fit the data properly, particularly in the tails, must be chosen, especially when the data are skewed. A recent study proposed a skew-normal method. We propose a three-component normal mixture model and introduce separate treatment effects at different components of GA. We evaluate operating characteristics of mixture model, beta-binomial model, and skew-normal model through simulation. We also apply these three methods to data from two completed clinical trials from the USA and Australia. Finite mixture models are shown to have favorable properties in PTB analysis but minimal benefit for ePTB analysis. Normal models on log-transformed data have the largest bias. Therefore we recommend finite mixture model for PTB study. Either finite mixture model or beta-binomial model is acceptable for ePTB study.  相似文献   
199.
200.
In this article, we investigate the potential usefulness of the three-parameter transmuted generalized exponential distribution for analyzing lifetime data. We compare it with various generalizations of the two-parameter exponential distribution using maximum likelihood estimation. Some mathematical properties of the new extended model including expressions for the quantile and moments are investigated. We propose a location-scale regression model, based on the log-transmuted generalized exponential distribution. Two applications with real data are given to illustrate the proposed family of lifetime distributions.  相似文献   
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