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1.
Working memory training improves children's cognitive performance on untrained tasks; however, little is known about the underlying neural mechanisms. This was investigated in 32 typically developing children aged 10–14 years (19 girls and 13 boys) using a randomized controlled design and multi-modal magnetic resonance imaging (Devon, UK; 2015–2016). Training improved working memory performance and increased intrinsic functional connectivity between the bilateral intraparietal sulci. Furthermore, improvements in working memory were associated with greater recruitment of the left middle frontal gyrus on a complex span task. Repeated engagement of fronto-parietal regions during training may increase their activity and functional connectivity over time, affording greater working memory performance. The plausibility of generalizable cognitive benefits from a neurobiological perspective and implications for neurodevelopmental theory are discussed.  相似文献   
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Abstract

Carnosine was originally discovered in skeletal muscle, where it exists in larger amounts than in other tissues. The majority of research into the physiological roles of carnosine have been conducted on skeletal muscle. Given this and the potential for muscle carnosine content to be increased with supplementation, there is now a large body of research examining the ergogenic effects (or otherwise) of carnosine. More recent research, however, points towards a potential for carnosine to exert a wider range of physiological effects in other tissues, including the brain, heart, pancreas, kidney and cancer cells. Taken together, this is suggestive of a potential for carnosine to have therapeutic benefits in health and disease, although this is by no means without complication. Herein, we will provide a review of the current literature relating to the potential therapeutic effects of carnosine in health and disease.  相似文献   
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ABSTRACT

This forum brings together food, (in)security, and communication. The authors participating in this forum center communication as both process and tool for understanding, mitigating, and making meaning of food (in)security. The nine authors together discuss the role of communication in food (in)security, the central challenges for scholars and practitioners working on food (in)security, and the creative possibilities and impacts influencing the future of food (in)security. The forum produces a call for applied scholars to re-imagine communication frameworks in order to make meaningful differences in their communities.  相似文献   
4.
Measuring Search Engine Quality   总被引:12,自引:3,他引:9  
The effectiveness of twenty public search engines is evaluated using TREC-inspired methods and a set of 54 queries taken from real Web search logs. The World Wide Web is taken as the test collection and a combination of crawler and text retrieval system is evaluated. The engines are compared on a range of measures derivable from binary relevance judgments of the first seven live results returned. Statistical testing reveals a significant difference between engines and high intercorrelations between measures. Surprisingly, given the dynamic nature of the Web and the time elapsed, there is also a high correlation between results of this study and a previous study by Gordon and Pathak. For nearly all engines, there is a gradual decline in precision at increasing cutoff after some initial fluctuation. Performance of the engines as a group is found to be inferior to the group of participants in the TREC-8 Large Web task, although the best engines approach the median of those systems. Shortcomings of current Web search evaluation methodology are identified and recommendations are made for future improvements. In particular, the present study and its predecessors deal with queries which are assumed to derive from a need to find a selection of documents relevant to a topic. By contrast, real Web search reflects a range of other information need types which require different judging and different measures.  相似文献   
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The purpose of this study was to describe the development of elementary students' skill in making predictions and of their understanding of what predicting means. The study involved observing and assessing the performance of 167 children on the Physical Manipulation Test (PMT), a test involving the manipulation of science materials and equipment. Children were interviewed about what they understand predicting to mean, how they use it at school and at home, and why they think it is important. For each of the seven topics tested, even the youngest children were able to offer predictions. Accuracy varied with the topic, increasing between Grades 1 and 4 and leveling off after that. The increase in skill involved children's growing ability to attend to patterns discerned through their own observations. Four levels in the development of predicting skill, as it relates to particular topics, are described. Children's understanding of predicting showed steady improvement through Grade 6. Children's awareness of their use of predicting at school and at home, and their ability to explain the importance of predicting, also increased through Grades 1 to 6, with a spurt at Grade 4. Children understood predicting to be an internal process in which one uses knowledge to anticipate a future event; they regarded predicting as an important way of being intellectually involved with the world.  相似文献   
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Although work-family benefits are increasingly important organizational policies, limited research addresses the impact of communication on benefit utilization. However, communication is significant because the perceived appropriateness of work-family benefits emerges through interaction. For example, when coworkers complain about "picking up the slack" for those using family leave, their discourse may impact future decisions of other workers regarding whether they utilize the work-family benefits available to them. We apply Giddens' (1984) Structuration Theory to examine organizational members' discursive responses to conditions (and contradictions) present in utilizing work-family benefits in a governmental organization. We argue the daily discursive practices of individuals can either reinforce or undermine formally stated work-family initiatives, and in turn discuss the implications of this "structuration" of policy.  相似文献   
10.
One of the highest priorities in today's hospitals is the provision of quality care to patients. The medical librarian has an increased responsibility to furnish quality information to the medical staff. Traditional methods of reference service continue to work well, but it is increasingly important for librarians to become more directly involved in hospital quality assurance (QA) activities. Occurrence screening is one system of QA where the librarian can make a difference.  相似文献   
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