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This study explores science communication on Twitter by investigating a sample of tweets referring to academic papers in five different scientific fields. The specifications of science communicators on Twitter, the characteristics of those who initiate actions (by tweeting), the extent and quality of reactions (retweeting), individual and group interactions, and the distribution of tweets across types of engagement in the process of science communication (i.e., dissemination, consultation, and evaluation) were explored. A broad array of actors is involved in the communication of science on Twitter, with individual citizens and individual researchers playing an important role. In principle, this is promising for creating direct interaction, which can be difficult through more traditional mass media. The vast majority of communication activities regarding academic papers is undigested dissemination with almost no sign of debate, contestation, or collective reflection. Another general finding of this study is that bot accounts play a major role in the science communication landscape on Twitter.  相似文献   
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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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In collaborative problem solving, children produce and evaluate arguments for proposals. We investigated whether 3- and 5-year-olds (N = 192) can produce and evaluate arguments against those arguments (i.e., counter-arguments). In Study 1, each child within a peer dyad was privately given a reason to prefer one over another solution to a task. One child, however, was given further information that would refute the reasoning of their partner. Five-year-olds, but not 3-year-olds, identified and produced valid and relevant counter-arguments. In Study 2, 3-year-olds were given discourse training (discourse that contrasted valid and invalid counter-arguments) and then given the same problem-solving tasks. After training, 3-year-olds could also identify and produce valid and relevant counter-arguments. Thus, participating in discourse about reasons facilitates children’s counter-argumentation.  相似文献   
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