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Tested the hypothesis that students' metacognition would be enhanced on content that aroused situational interest or that was related to students' topic interests. A metacognitive evaluation procedure was used in which students estimated their word knowledge, which was then determined objectively by a multiple-choice vocabulary test. Students could then update their vocabulary knowledge by reading a passage dealing with heart disease in which all of the previously encountered words were defined explicitly or implicitly. With differences in prior knowledge controlled, nursing students, for whom the content was related to topic interests, made more accurate metacognitive judgments than did freshmen. None of the other main effects or interactions was significant. The implications of the findings for research on interest, its relationship to prior knowledge, and the assessment of metacognition are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Tobias Buehler 《电子产品世界》2005,(1):113-115
10多年前,当第一代蜂窝电话出现时,采用了许多分立功率器件.第一代手机显得很笨重,高功耗使得待机时间和通话时间都很短.为了响应客户对外形更小,性能更高的无线电子设备不断增长的需求,工程师发展了许多先进的设计技术.这些技术既可缩小印刷电路板(PCB)尺寸,又可以提供更快更高效的性能. 相似文献
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Tobias Gawron-Deutsch Friederich Kupzog Alfred Einfalt 《e & i Elektrotechnik und Informationstechnik》2014,131(3):91-98
The growing share of volatile distributed generation in the electric power grids results in increased local network utilisation and challenges the conventional strategies for maintaining the system balance. While grid extensions and smart grid solutions are considered for network utilisation issues, new market mechanisms are in focus for the balancing challenge. It can be expected that distributed generators on one hand will be able to supply only part of their available power to the grid in peak times, and on the other hand will have (potentially changing) contracts with different trans-regional virtual power plants. Against this background it will be necessary to define rules dealing with expected network access conflicts. One strategy also followed in this work is to find market mechanisms that support economically efficient network extension. Such mechanisms will have to include local flexibility markets that allow for compensating network bottlenecks. This work proposes strategies and technical interfaces for coordinating market and grid operation by means of a “Flexibility Operator”. Its integration into a holistic smart grid concept is discussed. 相似文献
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Andrea Nolte Susanne Hossfeld Marcell Post Jan Niederlaender Tobias Walker Christian Schlensak Hans Peter Wendel 《Journal of materials science. Materials in medicine》2014,25(9):2121-2130
Chitosan is used in several pharmaceutical and medical applications, owing to its good cytocompatibility and hemocompatibility. However, there are conflicting reports regarding the biological activities of chitosan with some studies reporting anti-inflammatory properties while others report pro-inflammatory properties. In this regards we analyzed the endotoxin content in five different chitosans and examined these chitosans with their different deacetylation degrees for their hemocompatibility and cytocompatibility. Therefore, we incubated primary human endothelial cells or whole blood with different chitosan concentrations and studied the protein and mRNA expression of different inflammatory markers or cytokines. Our data indicate a correlation of the endotoxin content and cytokine up-regulation in whole blood for Poly-Morpho-Nuclear (PMN)-Elastase, soluble terminal complement complex SC5b-9, complement component C5/C5a, granulocyte colony-stimulating factor, Interleukin-8 (IL), IL-10, IL-13, IL-17E, Il-32α and monocyte chemotactic protein-1. In contrast, the incubation of low endotoxin containing chitosans with primary endothelial cells resulted in increased expression of E-selectin, intercellular adhesion molecule-1, vascular cell adhesion protein-1, IL-1β, IL-6 and IL-8 in endothelial cells. We suggest that the endotoxin content in chitosan plays a major role in the biological activity of chitosan. Therefore, we strongly recommend analysis of the endotoxin concentration in chitosan, before further determining if it has pro- or anti-inflammatory properties or if it is applicable for pharmaceutical and medical fields. 相似文献
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