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This article describes the ongoing efforts at University of Nevada, Las Vegas (UNLV) Libraries to evolve the role of the institutional repository (IR) and to effectively position it within the context of the Libraries’ collections, research support, and scholarly communication services. A major component of this process is re-examining the fundamental aims of the IR and aligning it to the Libraries and the campus strategic goals. The authors situate UNLV Libraries’ experience within the context of the current literature to provide background and reasoning for our decision to pursue two, at times conflicting, aims for the IR: one for scholarly communication and another for research administration. 相似文献
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Daniel Maier A. Waldherr P. Miltner G. Wiedemann A. Niekler A. Keinert 《Communication methods and measures》2018,12(2-3):93-118
ABSTRACTLatent Dirichlet allocation (LDA) topic models are increasingly being used in communication research. Yet, questions regarding reliability and validity of the approach have received little attention thus far. In applying LDA to textual data, researchers need to tackle at least four major challenges that affect these criteria: (a) appropriate pre-processing of the text collection; (b) adequate selection of model parameters, including the number of topics to be generated; (c) evaluation of the model’s reliability; and (d) the process of validly interpreting the resulting topics. We review the research literature dealing with these questions and propose a methodology that approaches these challenges. Our overall goal is to make LDA topic modeling more accessible to communication researchers and to ensure compliance with disciplinary standards. Consequently, we develop a brief hands-on user guide for applying LDA topic modeling. We demonstrate the value of our approach with empirical data from an ongoing research project. 相似文献
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Danny Bavli Elishai Ezra Daniel Kitsberg Margarita Vosk-Artzi Shashi K. Murthy Yaakov Nahmias 《Biomicrofluidics》2016,10(2)
Cell-cell interactions play a key role in regeneration, differentiation, and basic tissue function taking place under physiological shear forces. However, current solutions to mimic such interactions by micro-patterning cells within microfluidic devices have low resolution, high fabrication complexity, and are limited to one or two cell types. Here, we present a microfluidic platform capable of laminar patterning of any biotin-labeled peptide using streptavidin-based surface chemistry. The design permits the generation of arbitrary cell patterns from heterogeneous mixtures in microfluidic devices. We demonstrate the robust co-patterning of α-CD24, α-ASGPR-1, and α-Tie2 antibodies for rapid isolation and co-patterning of mixtures of hepatocytes and endothelial cells. In addition to one-step isolation and patterning, our design permits step-wise patterning of multiple cell types and empty spaces to create complex cellular geometries in vitro. In conclusion, we developed a microfluidic device that permits the generation of perfusable tissue-like patterns in microfluidic devices by directly injecting complex cell mixtures such as differentiated stem cells or tissue digests with minimal sample preparation. 相似文献
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ABSTRACTDue to budget constraints, schools in the United States have increasingly turned to community arts organizations for support. School-community arts partnership stakeholders collaborate because of shared missions to provide students with valuable arts learning experiences. Investigations of these initiatives indicate that these partnerships improve arts learning opportunities and increase public support and resources for arts education. However, not much is known about the experiences and perspectives of the arts organizations that participate in these partnerships. Coordinating collective efforts with a multitude of institutions and interests poses challenges. In this study, we examine survey data collected from arts organization administrators who participated in a large-scale school-community arts partnership initiative. We find that these organizations are generally positive about their impacts on students’ educational outcomes, but there is substantial variation in these views. We also find that organizations differ in their levels of support for these collective efforts. Sources of this variation appear to be attributable to organizations’ preexisting resources and extent to which they are established. While this difference in levels of support is potentially inevitable, we find evidence that the operations handled by the “backbone” organization, i.e. the initiative’s facilitators and overseers, can significantly influence organizations’ levels of support for these efforts. Organizations are more likely to support these collaborative efforts when they believe the backbone organization ensures transparency with initiative operations, provides regular, effective communication, and effectively resolves competing priorities. 相似文献
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José Roberto Andrade do Nascimento-Junior Leonardo de Sousa Fortes Gabriel Lucas Morais Freire Daniel Vicentini de Oliveira Lenamar Fiorese Lorcan Donal Cronin 《Measurement in physical education and exercise science》2020,24(1):11-24
ABSTRACTThis research adapted the Life Skills Scale for Sport (LSSS) into Portuguese and provided evidence for its construct validity. Study 1 included four translators and five academics who developed a Portuguese version of the LSSS (P-LSSS). During this study, evidence for the content and substantive aspects of construct validity was provided using an expert panel and 25 sports participants. Study 2 included 413 participants that completed the P-LSSS. Within this study, evidence for the structural aspect of construct validity was provided via factor analyses. Study 3 included 134 participants who completed the P-LSSS and a measure of motivation. This study provided evidence for the external aspect of construct validity, with results showing more self-determined motivation had positive relationships with participant’s life skills development. Overall, our findings provided evidence for the construct validity of P-LSSS scores. Researchers and practitioners can use the P-LSSS to assess life skills development within sports participants. 相似文献