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With the rise of microfluidics for the past decade, there has come an ever more pressing need for a low-cost and rapid prototyping technology, especially for research and education purposes. In this article, we report a rapid prototyping process of chromed masks for various microfluidic applications. The process takes place out of a clean room, uses a commercially available video-projector, and can be completed in less than half an hour. We quantify the ranges of fields of view and of resolutions accessible through this video-projection system and report the fabrication of critical microfluidic components (junctions, straight channels, and curved channels). To exemplify the process, three common devices are produced using this method: a droplet generation device, a gradient generation device, and a neuro-engineering oriented device. The neuro-engineering oriented device is a compartmentalized microfluidic chip, and therefore, required the production and the precise alignment of two different masks.  相似文献   
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The purpose of this investigation was to examine the efficacy of a new preschool oral language and early literacy curriculum package (Teaching Early Literacy and Language [TELL]) for children with developmental speech and/or language impairment (DSLI) either as a primary (e.g., specific to speech and/or language) or secondary impairment (e.g., developmental delay that includes DSLI). Participants included 118 children (30 females, 88 males, M age = 53.58 months) with DLSI and their 29 preschool teachers. The design was a randomized controlled trial (RCT) with assignment to experimental versus contrast conditions at the classroom level. Teachers in TELL classes received formal training, in-class support, and mentoring to implement the curriculum. Dependent measures for the children included scores on the Clinical Evaluation of Language Fundamentals-Preschool 2nd edition (CELF-P2), the Phonological Awareness Literacy Screening for Preschool (PALS-PreK), the Renfrew Bus Story (BUS), and a receptive and expressive vocabulary measure developed for this investigation (VOCAB). Results indicated that when compared to the contrast group, children in the TELL condition demonstrated greater gains on the phonological awareness subtest of the CELF-P2, the sentence length score of the BUS, the letter sounds, beginning sound awareness, and rhyme awareness subtests of the PALS-PreK, and VOCAB. Results suggest that the TELL curriculum package has promise for promoting gains in early literacy and oral language skills in preschool children with DLSI.  相似文献   
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In this article, the author attempts to oppose the traditional school pedagogy, which he labels conceptual, with non-classical padagogy of metaphors. According to the author, this type of pedagogy is a better fit for the human mind.  相似文献   
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In the article we solve path planning task for an agent being multirotor unmanned aerial vehicle (multicopter). We propose an approach of estimating path geometry constraints based on UAV flight dynamics model and control constraints. Than we introduce a new path finding method which takes into consideration those geometry constraints and study this method both theoretically and empirically.  相似文献   
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