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Brian R. Belland 《Educational Psychology Review》2011,23(4):577-600
Problem solving is an important skill in the knowledge economy. Research indicates that the development of problem solving
skills works better in the context of instructional approaches centered on real-world problems. But students need scaffolding
to be successful in such instruction. In this paper I present a conceptual framework for understanding the effects of scaffolding.
First, I discuss the ultimate goal of scaffolding—the transfer of responsibility—and one way that scholars have conceptualized
promoting this outcome (fading). Next, I describe an alternative way to conceptualize transfer of responsibility through the
lens of distributed cognition and discuss how this lens informs how to promote transfer of responsibility. Then I propose
guidelines for the creation of problem solving scaffolds to support transfer of responsibility and discuss them in light of
the literature. 相似文献
955.
Justin X. Nicoll Andrew J. Galpin Donald B. Thomason Christopher A. Moore 《European Journal of Sport Science》2017,17(9):1194-1202
Purpose: There is a paucity of research investigating the expression of mitogen-activated protein kinases (MAPK) in chronically trained (CT) athletes. Thus, it is unclear how MAPK may contribute to performance and muscle adaptation in CT subjects. The purpose of this study was to determine MAPK total protein, and phosphorylated expression of extracellular signal-regulated kinases 1 and 2 (ERK1/2), c-Jun N-terminal kinase (JNK), and p38-MAPK (p38) between untrained, and chronically trained runners. Methods: Tissue samples were analysed from sedentary (SED; n?=?5) controls and chronically trained runners (CT; n?=?5). Resting muscle biopsy samples were analysed for total-MAPK – and ratio of phosphorylated/total (p-MAPK) – ERK1/2, JNK, and p38-MAPK via western blotting. Mann–Whitney U tests and effect sizes were utilized to determine differences in total MAPK protein content and phosphorylation status between SED and CT subjects. Results: There was no difference in total-MAPK expression between SED and CT (p?>?.05). p-p38-MAPK tended to be greater for CT compared to SED (p?=?.07). There were moderate effect sizes of decreased pERK/total-ERK (d?=??0.69) and increased pJNK/total-JNK (d?=?0.54) in CT compared to SED. There was a positive correlation between p-p38-MAPK/total-MAPK and the percentage of type I fibres (r?=?0.73, p?=?.016). Conclusion: Contrary to previous studies, chronic endurance training does not greatly influence total MAPK protein expression in chronically trained runners. However, resting phosphorylation of p38-MAPK may contribute to enhanced oxidative metabolism at chronically trained levels. These alterations are likely involved in the different physiological adaptations that occur following long-term training or at highly competitive levels. 相似文献
956.
Peter B. Smith Cláudio V. TorresAlena Chudzikova Serdar DegirmenciogluFrancisco Donoso-Maluf Nancy Chen Yi FengCharles Harb Brad JacksonSigmar Malvezzi Andrew MogajiJuan Carlos Pastor Lorena Perez-FlorianoB.N. Srivastava Günter StahlStephanie Thomason Vladimir Yanchuk 《Int J Intercult Relat》2011,35(4):440-451
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Olivier Chapelle Shihao Ji Ciya Liao Emre Velipasaoglu Larry Lai Su-Lin Wu 《Information Retrieval》2011,14(6):572-592
We study the problem of web search result diversification in the case where intent based relevance scores are available. A
diversified search result will hopefully satisfy the information need of user-L.s who may have different intents. In this
context, we first analyze the properties of an intent-based metric, ERR-IA, to measure relevance and diversity altogether.
We argue that this is a better metric than some previously proposed intent aware metrics and show that it has a better correlation
with abandonment rate. We then propose an algorithm to rerank web search results based on optimizing an objective function
corresponding to this metric and evaluate it on shopping related queries. 相似文献
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Erica Rosenfeld Halverson Damiana Gibbons Shelby Copeland Alon Andrews Belen Hernando Llorens Michelle B. Bass 《Learning, Media and Technology》2014,39(3):386-403
In this article, we explore how youth audiences evaluate the quality of youth-produced films. Our interest stems from a dearth of ways to measure the quality of what youth produce in artistic production processes. As a result, making art in formal learning settings devolves into either romanticized creativity or instrumental work to improve skills in core content areas. We conducted focus groups with 38 youth participants where they viewed four different films produced by the same youth media arts organization that works with young people to produce short-form, autobiographical documentaries. We found that youth focused their evaluations on identifying the films' genre and content and on assessing how well the filmmakers' creative decisions fit with identifications of genre and content. Evaluations were mediated by audiences' expectations and seemed to inform judgments of quality and creativity. We hope that our work can inform the design of formal learning spaces where young people are producing narrative art. 相似文献
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