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741.
Abstract

Public service librarians, eager to comply with Association of College and Research Libraries guidelines, face challenges in the rush to support distance education programs in higher education. Distance education students doing serials research encounter significant problems. In this column the author identifies and discusses issues related to the instruction, reference, and access needs of such students. Serials Review 2002; 28:206–212.  相似文献   
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747.
A wellknown result of CHERNOFF on the convergence rate of the 2nd kind error in testing two simple hypotheses is generalized to the case of finite hypotheses by help of methods of linear programming and the asymptotic behaviour of the corresponding least favourable distribution is investigated.  相似文献   
748.
The purpose of this research study was to increase our understanding of how families living in poverty successfully meet life challenges. Family resiliency provided the theoretical framework for examining family coping and adaptation. This study used a purposive sample of women (N = 128) in families with children attending Head Start. All families lived below or at poverty level, most with 11th grade education or high-school/GED diploma. Content analysis methods were used for data analysis. Results of this study identify the characteristics that promote competence, including how individual, family, and environmental factors are potential stressors that also may serve to promote family resilience. The data indicate that family love and mutual support, as well as faith, help stressed families cope and maintain meaning in spite of lack of control over life circumstances resulting from economic poverty.  相似文献   
749.
In this article we examine the prevalence of and associations between sexual orientation–based verbal harassment and reported utilization of health services across levels of sexual orientation in a diverse sample of adult recipients of Los Angeles County–funded HIV-related health and social services. Thirty-two percent reported they had experienced verbal harassment, the majority (80.3%) of whom identified as lesbian, gay, or bisexual (LGB). Those who reported being verbally harassed received significantly more services overall than those who were not verbally harassed, and service utilization varied by sexual orientation. These findings inform future efforts to identify and assess social discrimination in health and social service settings.  相似文献   
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The distribution of ant colonies within a community is often well defined, yet this distribution can change due to changing environmental conditions, resource availability, and colony growth. In this study, structure infesting ant communities were sampled for one year within three Puerto Rican housing developments of different ages. These developments represented environments in different stages of recovery after a disturbance (secondary succession). Spatial mapping was used to plot the distribution and abundance of ant communities within these developments. At the beginning of the study, the youngest housing development (1 year since construction), had the fewest number of species present (ave. 1.6 per house). The second housing development (4 years old) had a greater number of species (ave. 2.6 per house), and a greater sampling frequency (the same species collected at multiple houses) than Site 1. The oldest development (8 years old) had both the greatest number of species (ave. 2.7 per house), and sampling frequency of the three sites. In all developments, the number of species, sampling frequency, and ant biomass increased throughout the year as colonies grew and foraging ranges expanded. It was observed in all developments, that species coexistence also increased throughout the year. As colony populations increased, there was a greater occurrence of multiple species being collected at the same sample house. In the youngest development, the two most dominant species increased in numbers during the year and began to be collected from the same sample houses. Spatial diagrams documented that multiple species in the older housing developments (later stages of succession), also shared a common distribution. Even the most dominant species (S. invicta) in all three sites, did not exclude additional species from foraging within its established range.  相似文献   
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