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Karen D. Arnold 《About Campus》2007,12(5):2-9
Rather than dwelling on why too many men don't succeed in college, trekker Karen Arnold examines the features of an experience in which many men do excel: the long hike from Georgia to Maine. Educators can learn why accomplishing this feat may be more rewarding than college. 相似文献
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The University of North Texas (UNT) Libraries are funded almost entirely by undergraduate student use fees. As the undergraduate enrollment has plateaued in recent years, the libraries have not been able to keep up with rising costs, resulting in a series of cuts to the materials budget totaling around $3.25 million. While some of these cuts took the form of reductions in firm orders and dissolution of approval plans, for the past three years the bulk has come from cancellations of serials and electronic resources. With each year’s cuts, the UNT Collection Development department has been forced to modify and refine their deselection process. This article will show the development of UNT’s strategy for determining cancellations using a variety of methods (overlap analysis, usage statistics, faculty input) and tools (EBSCO Usage Consolidation, Serials Solutions 360). 相似文献
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Biomimetic scaffolds approaching physiological scale, whose size and large cellular load far exceed the limits of diffusion, require incorporation of a fluidic means to achieve adequate nutrient/metabolite exchange. This need has driven the extension of microfluidic technologies into the area of biomaterials. While construction of perfusable scaffolds is essentially a problem of microfluidic device fabrication, functional implementation of free-standing, thick-tissue constructs depends upon successful integration of external pumping mechanisms through optimized connective assemblies. However, a critical analysis to identify optimal materials/assembly components for hydrogel substrates has received little focus to date. This investigation addresses this issue directly by evaluating the efficacy of a range of adhesive and mechanical fluidic connection methods to gelatin hydrogel constructs based upon both mechanical property analysis and cell compatibility. Results identify a novel bioadhesive, comprised of two enzymatically modified gelatin compounds, for connecting tubing to hydrogel constructs that is both structurally robust and non-cytotoxic. Furthermore, outcomes from this study provide clear evidence that fluidic interconnect success varies with substrate composition (specifically hydrogel versus polydimethylsiloxane), highlighting not only the importance of selecting the appropriately tailored components for fluidic hydrogel systems but also that of encouraging ongoing, targeted exploration of this issue. The optimization of such interconnect systems will ultimately promote exciting scientific and therapeutic developments provided by microfluidic, cell-laden scaffolds. 相似文献
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