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The librarians at four hospital libraries describe the electronic reference service, "Ask A Librarian," offered at their institutions. The hospitals are vastly different in size and in number of library staff, and offer the "Ask A Librarian" service to different clientele. The article illustrates that both large hospitals with a large library staff and small hospitals with a solo librarian and some volunteers can offer this type of service.  相似文献   
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Florida-James G  Donaldson K  Stone V 《Journal of sports sciences》2004,22(10):967-80; discussion 980
Athens sits in a basin approximately 450 km2 in area, surrounded by mountains and open sea. Anthropogenic emissions in conjunction with the topographical and meteorological conditions can result in high air pollution within the city. The pollutants of concern for athletes competing in Athens 2004 appear to be nitrogen dioxide (NO2), ozone and particulate (PM10) pollution. Exposure to elevated ozone concentrations has been reported to give rise to symptoms that include cough, chest pain, difficulty in breathing, headache, eye irritation and a decrease in forced expiratory volume in one second. All of these effects are likely to impact upon performance, and several studies of cyclists suggest this to be the case. In contrast, the impact of ambient concentrations of NO2 appears to be negligible on normal activities, but at high exercise intensities the impact remains unclear. The use of currently available information and models to predict the effect of ozone and other pollutants on elite athletes is problematical, since such models are based upon significantly lower ventilation rates than those achieved by some elite athletes. In addition, it is already known that the response to ozone can vary somewhat between individuals. Since the individuals who will be competing in Athens are physiologically very different to the participants in most published studies, it is difficult to predict individual responses. There is some evidence to indicate that adaptation to the adverse health and performance effects of ozone can occur, so that performance is partially recovered on re-exposure. The adaptation is not seen in all studies and appears to be dependent on several factors, including the initial sensitivity of the individual to ozone. Antioxidant supplementation has also been shown in some studies to partially ameliorate the adverse effects of ozone by counteracting the oxidative stress mechanism associated with this pollutant. Whether this transfers to performance enhancement per se remains unclear at present. Additional research is required to gain a sound understanding of the effects of a complex mixed air pollution exposure on the pulmonary function and performance of athletes exercising at high work intensities.  相似文献   
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This study examined the effects of social influences in the lives of an ethnically diverse sample of fifth through eighth grade students with and without learning disabilities (LD) using survey data and academic achievement scores collected in 19 Chicago public schools from 1993–1997. Similarities and differences in student perceptions of school, family, and peer group contexts were examined. In addition, longitudinal data were analyzed using hierarchical linear modeling (HLM) to identify contextual influences on changes in student reading achievement over time. Comparisons of student responses confirm and extend existing findings in the literature concerning the perceptions of students with LD of their social environments. In particular, having a learning disability was associated with consistent, mostly negative, effects on social relations across the contexts of students’ lives, regardless of gender, race, grade, and socioeconomic status. In addition, student perceptions of their friendship groups were found to have small, but significant, effects on their growth in reading achievement over the course of middle school. While students with and without LD had somewhat different views of their social contexts, the processes working within these environments appeared to affect their reading achievement in similar ways. The results suggest that careful attention should be paid to the social contexts of students’ lives when planning academic interventions.  相似文献   
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How do public libraries develop their collections of high-demand materials for the “I want it now” generation? Ten public libraries’ holdings of fiction and nonfiction bestseller titles were observed over a four-week period. The number of copies rose fairly consistently, with the five fiction titles having roughly about twice the number of copies as the five nonfiction titles. The ratio of holds to copies averaged 2.7:1 and ranged from 0.8:1 to 6.5:1. Demand for e-books was consistently higher than the number of copies available, averaging more than 4:1 across all libraries.  相似文献   
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