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121.
In recent years, there has been a strong push to transform STEM education at K-12 and collegiate levels to help students learn to think like scientists. One aspect of this transformation involves redesigning instruction and curricula around fundamental scientific ideas that serve as conceptual scaffolds students can use to build cohesive knowledge structures. In this study, we investigated how students use mass balance reasoning as a conceptual scaffold to gain a deeper understanding of how matter moves through biological systems. Our aim was to lay the groundwork for a mass balance learning progression in physiology. We drew on a general models framework from biology and a covariational reasoning framework from math education to interpret students' mass balance ideas. We used a constant comparative method to identify students' reasoning patterns from 73 interviews conducted with undergraduate biology students. We helped validate the reasoning patterns identified with >8000 written responses collected from students at multiple institutions. From our analyses, we identified two related progress variables that describe key elements of students' performances: the first describes how students identify and use matter flows in biology phenomena; the second characterizes how students use net rate-of-change to predict how matter accumulates in, or disperses from, a compartment. We also present a case study of how we used our emerging mass balance learning progression to inform instructional practices to support students' mass balance reasoning. Our progress variables describe one way students engage in three dimensional learning by showing how student performances associated with the practice of mathematical thinking reveal their understanding of the core concept of matter flows as governed by the crosscutting concept of matter conservation. Though our work is situated in physiology, it extends previous work in climate change education and is applicable to other scientific fields, such as physics, engineering, and geochemistry.  相似文献   
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Prediction markets designed to predict terrorism through traders’ investments on the likelihood of specific terrorist attacks are, strictly speaking, enabling those traders to bet on terrorism. Betting on terrorist attacks, like some other forms of betting on death, has been accused of being repugnant. In this paper, it is argued that while government-backed effective intelligence-gathering prediction markets on terrorism (PMsoT) might elicit feelings of repugnance, those feelings are likely to be misguided. The feelings of repugnance arise because PMsoT are assumed to be associated with terrorism in encouraging and endorsing ways and with human death in a disrespectful way. However, it is argued that these feelings of repugnance are misguided in the case of government-backed effective intelligence-gathering PMsoT because the purpose and effect of such prediction markets, and (on balance) the trading they encourage, is to prevent and renounce terrorism and show respect for matters of life and death.  相似文献   
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The classical criteria for controllability and observability are given a tensorial formulation which is then extended into Boolean form directly related to a digraph interpretation of system structure. This is examined in detail with particular reference to group theoretic aspects, invariant properties under transformation, the term rank test and the existence of zero eigenvalues.Within this framework the structural design concepts of potential controllability and observability are presented in generalised terms.  相似文献   
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It's something they can relate to. You know, assimilate. They go there, talk in Spanish, not worry about it, drink, have fun, do it all in a language they're accustomed to, or at least with people they feel more comfortable with. I guess that's why a lot of them come Monday nights from these distances. That's what I was trying to explain to Chris. If you have a Latino night it's going to be successful because us as Latinos don't have a lot of options for us to go or places for us to go.  相似文献   
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There is an established, if weak, inverse relationship between levels of English language proficiency and academic performance in higher education. In response, higher education institutions (HEIs) insist upon minimum entry requirements concerning language for international applicants. Many HEIs now also offer pre‐sessional English courses to bring applicants up to the designated language requirement. This paper revisits the research into language proficiency and academic performance using data on all full‐time students (17,925) attending a major UK HEI in the academic year 2011–2012, 4,342 of whom were non‐native English speakers. The findings confirm that while higher International English Language Testing System (IELTS) marks at entry translate into higher grade point averages (GPAs), students who undertake pre‐sessional courses do notably worse in GPA terms than students who arrive with acceptable (for the course) IELTS scores. These findings suggest HEIs (and, by extension, international students) could benefit from a review regarding the appropriateness of current pre‐sessional English language proficiency programmes.  相似文献   
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