A Current Snapshot of Institutional Repositories: Growth Rate, Disciplinary Content and Faculty Contributions

INTRODUCTION The purpose of this study was to examine current institutional repository (IR) content in order to assess the growth and breadth of content as it reflects faculty participation, and to identify successful strategies for increasing that participation. Previous studies have shown that faculty-initiated submissions to IRs, no matter the platform, are uncommon. Repository managers employ a variety of methods to solicit and facilitate faculty participation, including a variety of print marketing tools, presentations, and one-on-one consultations. METHODS This mixed method study examined faculty content in IRs through both a quantitative analysis of repository content and growth rate and a qualitative survey of repository administrators. Repositories using the Digital Commons repository platform, hosted by Berkeley Electronic Press, were examined in the fall and winter of 2013-2014 to assess the disciplinary scope of faculty content (n=107) and to measure the growth rate of IR content (n=203). Repository administrators at 205 institutions were surveyed to investigate what methods they used to facilitate faculty participation and their perceptions about the effectiveness of these methods. RESULTS Mean and median growth rates of IRs have increased since measured in 2007, with variance depending upon size and type of academic institution and age of the IR. Disciplinary content in IRs is unevenly distributed, with the Sciences predominantly represented. IR administrators remain actively involved in the submission process and in the promotion of their IRs. Personal contact with individuals or groups of faculty is the most used and successful interaction method. CONCLUSION Though IR growth rate has increased, the growth is not consistent across all IRs and does not yet pose a challenge to traditional models of scholarly publication. The rising amount of faculty content in IRs indicates faculty are increasingly willing to participate in the IR movement. However, faculty involvement may be more passive than active

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Determination of cloud microphysical properties by laser backscattering and extinction measurements

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Mitochondria were simultaneously isolated from striatum and cortex of adult rats and compared in functional assays for their sensitivity to calcium activation of the permeability transition. Striatal mitochondria showed an increased dose-dependent sensitivity to Ca2+compared with cortical mitochondria, as measured by mitochondrial depolarization, swelling, Ca2+uptake, reactive oxygen species production, and respiration. Ratios of ATP to ADP were lower in striatal mitochondria exposed to calcium despite equal amounts of ADP and ATP under respiring and nonrespiring conditions. The Ca2+-induced changes were inhibited by cyclosporin A or ADP. These responses are consistent with Ca2+activation of both low and high permeability pathways constituting the mitochondrial permeability transition. In addition to the striatal supersensitivity to induction of the permeability transition, cyclosporin A inhibition was less potent in striatal mitochondria. Immunoblots indicated that striatal mitochondria contained more cyclophilin D than cortical mitochondria. Thus striatal mitochondria may be selectively vulnerable to the permeability transition. Subsequent mitochondrial dysfunction could contribute to the initial toxicity of striatal neurons in Huntington's disease.</jats:p