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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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ABSTRACT

Due 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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Revolutions     
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On the fiftieth anniversary of the first publication of English in Education, this article reviews the journal's contribution to research and practice in the teaching of English. A thematic analysis based on close study of a sample of volumes is arranged chronologically (to show the development of ideas and practices) and thematically in terms of language mode (speaking; writing; reading, including new technologies). The article argues that the journal archive can shed light on the educational past in ways that can effectively inform the educational present and help to set agenda for the future.  相似文献   
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