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Droplet microfluidics enables powerful analytic capabilities but often requires workflows involving macro- and microfluidic processing steps that are cumbersome to perform manually. Here, we demonstrate the automation of droplet microfluidics with commercial fluid-handling robotics. The workflows incorporate common microfluidic devices including droplet generators, mergers, and sorters and utilize the robot''s native capabilities for thermal control, incubation, and plate scanning. The ability to automate microfluidic devices using commercial fluid handling will speed up the integration of these methods into biological workflows. 相似文献
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Recent research related to the design of science instruction is often based on conceptual change theory and requires assessments of what knowledge students bring to instruction. The premise of this study was that it is also important to understand when and how students apply their knowledge. Fourteen elementary and middle school teachers in an in-service physics course were asked to solve qualitatively a variety of series and parallel circuit problems and explicate their reasoning. These teachers were found to share a common core of strongly held propositions that formed a coherent, but incorrect and contradictory model of sequential current flow. Yet their predictions about the circuits were highly variable. The variability in predictions resulted from differences and contradictions in additional “protective belts” of propositions, and differences in the ways in which the teachers changed and selectively applied those propositions to different problems. Understanding the variations in not only what teachers knew, but also the differences in when and how they applied their knowledge complicated the task of designing instruction. However, it also made possible the design of more precise instruction in which the teachers were required to recognize, confront, and reconcile specific inconsistencies in their beliefs. 相似文献
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Diane M. Gayeski 《Performance Improvement Quarterly》1991,4(4):21-36
In response to the perceived need of many organizations to increase the quantity, quality, and timeliness of training, their shortage of experienced instructional developers, and constrained training budgets, software systems are being created to assist both novice and expert instructional technologists. The underlying philosophies and goals of such “ID automation” tools and their potential effects upon the organizations who adopt them as well as upon the human performance technology profession must be examined so that they will help to empower rather than hinder their users. 相似文献
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