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Summary.  To help to design vaccines for acquired immune deficiency syndrome that protect broadly against many genetic variants of the human immunodeficiency virus, the mutation rates at 118 positions in HIV amino-acid sequences of subtype C versus those of subtype B were compared. The false discovery rate (FDR) multiple-comparisons procedure can be used to determine statistical significance. When the test statistics have discrete distributions, the FDR procedure can be made more powerful by a simple modification. The paper develops a modified FDR procedure for discrete data and applies it to the human immunodeficiency virus data. The new procedure detects 15 positions with significantly different mutation rates compared with 11 that are detected by the original FDR method. Simulations delineate conditions under which the modified FDR procedure confers large gains in power over the original technique. In general FDR adjustment methods can be improved for discrete data by incorporating the modification proposed.  相似文献   
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Composition-consistent tournament solutions and social choice functions   总被引:1,自引:1,他引:0  
This paper introduces a new axiom for choice in preference profiles and tournaments, called composition-consistency. A social choice function is composition-consistent if it is non-sensitive to the cloning of one or several outcomes. The key feature of the composition consistency property is an operation concept called multiple composition product of profiles. The paper provides a brief overview of some social choice functions studied in the literature. Concerning the tournament solutions, it is proved that the Top Cycle, the Slater and the Copeland solutions are not composition-consistent, whereas the Banks, Uncovered Set, TEQ, Minimal Covering Set are composition-consistent. Moreover, we define the composition-consistent hull of a solution as the smallest composition-consistent solution containing . The composition-consistent hulls of the Top cycle and Copeland solutions are specified, and we give some hints about the location of the hull of the Slater set. Concerning social choice functions, it is shown that Kemeny, Borda and Minimax social choice functions are not composition-consistent, whereas the Paretian one is composition-consistent. Moreover, we prove that the latter is the composition-consistent hull of the Borda and Minimax functions.  相似文献   
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A meningococcal serogroup B (MenB) outbreak at a large public university prompted an emergency response to immunize undergraduates. Objective: To report on a successful meningococcal serogroup B (MenB) vaccine clinic response at a large public university. Methods: We assembled the team leaders to write this case report. Results: Activation of the emergency plan and points of dispensing required cooperation of many units on campus under the leadership of university health officials with support from Centers for Disease Control and Prevention, state division of public health and the city-county health department. Significant efforts to provide consistent messages to students and parents regarding the outbreak and the availability of the MenB vaccines were made. Volunteers were recruited to staff the clinics alongside university healthcare providers. Over 22,000 doses of vaccine were administered. Conclusion: We report our experience and lessons learned which may be helpful to universities in preventing and responding to disease outbreaks.  相似文献   
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VOLUNTAS: International Journal of Voluntary and Nonprofit Organizations - A social business responds to social problems usually ignored by institutions, mobilizing resources and generating...  相似文献   
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This article makes an initial analysis of the implications of income diversification for technical change and agricultural research policy in Africa, leading to two insights. First, that the dilution effect of income diversification means that, as the proportion of non‐farm income increases, so must the expected gains from adopting a new agricultural technology. Second, that diversified producers will face disproportionately large transactions costs associated with information acquisition to inform technology choice decisions. Two hypotheses about how diversified producers are likely to react are then explored. Both point to the conclusion that income diversification among the poor is likely to constrain significantly the direct poverty impacts of agricultural research. The policy implications of these findings are then considered.  相似文献   
8.
For many older adults having access to affordable health care is a major concern. The present study's goal was to examine what factors were related to individuals' knowledge of late-life health insurance. A total of 131 women and 116 men (all aged 55-71) answered questions about private, Medicare, Medigap, and long-term care insurances. In addition, they answered demographic, personality, and health status questions. Results revealed that different factors are related to men's and women's knowledge of late-life health insurance options implying genderspecific educational interventions would be more effective than current educational interventions.  相似文献   
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The 1994–2000 waves of the European Community Household Panel are used to study the earnings of immigrants as compared to native workers in 15 European countries. At the time of arrival, there is a significant negative partial effect of foreign birth on individual earnings compared to the native born in the destination of around 40%. These differences vary across origins and destinations and by gender. Immigrant earnings catch-up to those of the native born after around 18 years in the destination. Schooling matters more for earnings for women, whereas, language skills are relatively more important for men.
Barry R. ChiswickEmail:
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10.
Objective: This study examines the health insurance literacy, or the ability to use health insurance effectively, of college students. Participants: A total of 455 students from a large, public university completed an online questionnaire in November 2016. Methods: A questionnaire examined students’ knowledge of commonly encountered health insurance terms and ability to apply that knowledge to determine cost-sharing in a clinical setting. Results: The majority of students were able to correctly identify the most commonly encountered terms, but could not identify terms related to plan types and options. Eighty-eight percent of students could not determine their cost-sharing for two presented scenarios. Approximately half of the students indicated they had been confused about their health insurance plan, with one-quarter of students stopping or delaying medical care due to confusion. Conclusions: Outreach and education for students should target specific deficits in knowledge such as those identified in this study.  相似文献   
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