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901.
902.
Interest in understanding what constitutes effective instruction online continues to grow as more universities adopt mediated formats for teaching. However, engaging students in productive, content-related conversation in online courses remains challenging. Several variables may influence student willingness to talk in online classes – procedural justice, affect towards the instructor, and perceived cognitive learning – each with probable direct and indirect effects on student inclinations for communicating in the classroom. This study proposes a model predicting student willingness to talk in online classes. Results indicate initial support for the proposed model, and practical implications for instructors teaching online courses are suggested.  相似文献   
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904.
Running has been plagued with an alarmingly high incidence of injury, which has resulted in the exploration of interventions aimed at reducing the risk of running-related injury. One such intervention is the introduction of footwear that mimics barefoot running. These have been termed minimalist shoes.

Minimalist footwear aims to reduce the risk of injury by promoting adaptations in running biomechanics that have been linked to a reduction in both impact and joint forces. However, some studies have found that minimalist footwear may be beneficial to the runner as they promote favourable biomechanical adaptations, whilst other studies have found the opposite to be true.

Reasons for these conflicting results could be attributed to the lack of a definition for minimalist footwear. The aim of this review article is to provide a structural definition for minimalist footwear based on studies that have examined the influence of footwear on biomechanical variables during running.

Based on current literature, we define minimalist footwear as a shoe with a highly flexible sole and upper that weighs 200g or less, has a heel stack height of 20mm or less and a heel-toe differential of 7mm or less.  相似文献   

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This paper reports a survey of 16 to 17 year old students who took part in a school based project activity designed to motivate them to consider a career in engineering. The scheme can be considered a success in that an uppermost estimated figure of 19% more students were recruited to engineering undergraduate courses than might otherwise have been the case in the absence of the scheme. The price that was paid for this was that for every additional engineer recruited to an undergraduate course there were ten participants on the scheme. The way that youngsters make decisions about career choices is discussed in an attempt to throw some light on the mechanisms for uptake (and abandonment) of careers in engineering.  相似文献   
908.
The open science movement, although not new to social science broadly, has gained momentum recently within communication science. In response, journals in our field have begun encouraging open science practices, from data and materials sharing to submitting preregistered research reports. However, this momentum has also led to some confusion over what is and is not considered open science and what the value of open sciences practices is. In this editorial we lay out an “onion model” of open science that describes increasing levels of transparency and suggests how open science practices can be understood less as a revolutionary concept but more as a logical extension of some of the historical pillars of scientific norms. Through this model, we provide tangible steps for how scholars may begin thinking about how to introduce open science practices into their current and future empirical efforts.  相似文献   
909.
Following a general discussion on the philosophy and design of information systems, with particular attention to the definition, needs and psychology of the ultimate user of systems providing on-line access to biomedical information, the role of the documentalist, the differences between document retrieval and true information retrieval and the operational characteristics of on-line systems which affect their cost and hence their design and acceptability, the authors make some tentative predictions as to the future demand for such information retrieval services and their probable organizational form. A brief report is then presented on the principal findings and conclusions of a user's study of the Excerpta Medica system, the key features and history of which are briefly described. Based on the conclusions of this study, particularly as regards the complexity of the average search question, the role of the search formulators in determining the results of computer searching, the importance of secondary concepts for retrieval and the optimal level of specificity of a computer thesaurus, some of the changes in the Excerpta Medica system which are in the planning stage and will be incorporated into the system's Mark II version are outlined, as are the principal features of the two systems currently offering on-line access to the Excerpta Medica database in Western Germany and the U.S.A. Finally, attention is given to the planned partial hierarchic structuring of the Excerpta Medica thesaurus (Malimet), a project which is to be based largely on frequency counts of the existing database and the elimination of over-specific terms by posting under broader concepts. The results of some of the initial steps in this direction (i.e. frequency counts of portions of the database and the structuring of some of the terms used in the cancer field) are presented by way of illustration.  相似文献   
910.
Clusters,convergence, and economic performance   总被引:1,自引:0,他引:1  
This paper evaluates the role of regional cluster composition in regional industry performance. On the one hand, diminishing returns to specialization in a location can result in a convergence effect: the growth rate of an industry within a region may be declining in the level of economic activity of that industry. At the same time, positive spillovers across complementary economic activities can provide an impetus for agglomeration: the growth rate of an industry within a region may be increasing in the “strength” (i.e., relative presence) of related industries. Building on Porter (1998, 2003), we develop a systematic empirical framework to analyze the role of regional clusters – groups of closely related industries operating within a particular region – in the growth of regional industries. We exploit data from the US Cluster Mapping Project to examine the effects of agglomeration within regional clusters after controlling for convergence at the region-industry level. Our findings suggest that industries located in a strong cluster register higher employment and patenting growth. Regional industry growth also increases with the strength of related clusters in the region and with the strength of similar clusters in adjacent regions. We also find evidence of the complementarity between employment and innovation performance in regional clusters: both the initial employment and patenting strength of a cluster have a separate positive effect on the employment and patenting growth of the constituent industries. Finally, we find that new regional industries emerge where there is a strong cluster. These findings are consistent with multiple types of externalities arising in clusters, including knowledge, skills, and input–output linkages.  相似文献   
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