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ABSTRACT

The aims of this study were to identify profiles of sedentary behaviour (SB) patterns, based on leisure-time self-reported SB modalities (screen, educative, social, and relaxing) and to evaluate changes in these profiles over 2 years among Spanish youth aged 8–18 years. Latent profile analysis (LPA), a data-driven analytic approach, was used to identify groups of boys and girls (n = 1553; 48% girls; mean±SD age: 12.56 ± 2.49 y) with distinct SB profiles using the SB modalities (time/d) as input variables. Latent transition analysis, an extension of LPA that uses longitudinal data, was used to analyse 2-year changes in these profiles. At baseline, four and three SB profiles were found among boys (labelled: screen, educative, social, and relaxing) and girls (labelled: screen/social, educative, and relaxing), respectively. Overall, more girls (range: 48%-67%) had the same profile over time, than boys (40%-52%). Participants with a screen or relaxing SB profile at baseline were more likely to have an educative profile after 2 years. Youth with a social and an educative SB profile at baseline were more likely to transition to profiles characterized by higher screen and social SB, respectively. Using a novel and person-centered approach, this study identified gender-specific SB profiles that were moderately stable over time.  相似文献   
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In order to assess the current status of MEDLINE training provided by schools of library science, a survey was conducted of those schools having an educational identification code issued by the National Library of Medicine. Information was gathered on such variables as the instructors' background and preparation, the course objectives and content, and the amount of on-line experience provided to students in each of eleven programs. An evaluation of these measures indicates that more opportunities to gain experience in using MEDLINE should be initiated by library schools and that current efforts should be continued and expanded. Specific recommendations for accomplishing these goals are outlined; they are addressed to health sciences librarians, library school educators, the Medical Library Association, and the National Library of Medicine.  相似文献   
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In 2008 Meier and Conkling first tested Google Scholar's coverage of the engineering literature against citations gathered from the Compendex database. Since that time, other studies have used the same methodology and found improvement in Google Scholar's coverage. This study uses engineering dissertations from Proquest Dissertations & Theses to create a data set of citations for the comparison of fee-based databases, Compendex and Scopus, against Google Scholar. From 1950 to 2017 Google Scholar outperformed both Compendex and Scopus in discoverability of citations in nine engineering subjects. These results have implications for collection management and information literacy program planning for librarians.  相似文献   
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Polyvocal approaches allow researchers and informants to interact on a more equal footing and informants’ voices to be heard in the final text. But research methods intended to empower informants also can be a source of unanticipated authorial power ‐ the power to confront informants with unsolicited self‐reflections and to textualize people's lives and words. The authors reflect on those ethical dilemmas in this article.  相似文献   
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Increasingly, career centers on university and college campuses are making use of the World Wide Web to help their users with a myriad of career related needs. This technological service delivery mode has many advantages that will be briefly reviewed in this article. As well, a computer emphasis has the potential for drastically changing career centers as we know them: their traffic patterns, staffing needs, resource procurement, and perhaps most importantly, their outcomes in the lives of the students who make use of them. This article discusses these changes and through a review of seven critical issues, challenges the reader to closely examine the implications for technology within their own career centers.  相似文献   
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