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21.
What determines knowledge sourcing from host locations of overseas R&D operations? We investigate factors that influence the extent to which overseas R&D laboratories source knowledge from host locations. Drawing on both the capabilities perspective and the embeddedness perspective, we have developed a conceptual model and then examined it empirically focusing on overseas R&D labs of Japanese multinationals. Statistical findings from negative binomial regressions show that both technological capabilities of the lab and external embeddedness in the local scientific and engineering communities matter.  相似文献   
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A word problem that requires addition of fractions with different denominators was presented to 11 classes of 4th- or 5th-graders, 10 years of age. It had three answer alternatives: adding the denominators and numerators separately, transforming fractions into decimals before adding them, and the standard, most appropriate solution. Students in each class were required to choose an alternative themselves, state their reason for the choice, and discuss which alternative would be right. After whole-class discussion, they were asked to choose an alternative again and nominate the student who had offered the most plausible idea. Then students in six classes were informed which alternative was the most appropriate, whereas those in five classes were not. Finally, the students, irrespective of the presence/absence of feedback, were required to solve the initial problem without the alternatives as the post-test, and two new problems as the transfer test.The results showed that (a) the students could offer more or less plausible arguments for or against each alternative, which in most classes included the correct explanation; (b) both vocal and silent students could write a mathematical expression for the post-test problem and manipulated it correctly, incorporating other students' ideas presented during the discussion, with or without the teacher's feedback, though their generalization was rather limited; and (c) the students could recognize and memorize reasonable explanations offered by other students in the discussion.  相似文献   
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We propose an on-demand multiparth routing algorithm in a mobile ad hoc network for video transmission and evaluate its real world performance in video streaming application. There have been a number of multipath routing protocols extended from AODV which is a well-known single path routing protocol. Multipath routing protocols indicate good performance in the reduction of route discovery latency and unnecessary routing packets in simulations. We show that the route establishment using source route lists provided by us (Hu and Johnson, 2002) can reduce the route discovery latency, select stable routes automatically, and work well for live video streaming without limitation of the hop count based approaches. We evaluate this proposed method compared with the original AODV by using eight laptop PCs and demonstrate live streaming experiments.  相似文献   
25.
To clarify the physical and mental fatigue caused by intense exercise and the relationship between the two types of fatigue, we examined changes in anthropometric and biochemical variables, neutrophil function, and the Profile of Mood States (POMS) questionnaire in 13 female university judoists attending a one-week training camp. Blood glucose, total cholesterol, haemoglobin, leukocyte count, IgG, and phagocytic activity all decreased after the training camp compared with baseline (P < or = 0.046). Aspartate aminotransferase, lactate dehydrogenase, creatine kinase, and neutrophil oxidative burst activity increased after the training camp (P < or = 0.007). Of the POMS scores, that for Fatigue increased after the training camp (P = 0.041) and that for Vigour decreased (P = 0.042). The changes in several POMS scores correlated with the changes in blood biochemical variables. In particular, the change in Total mood disturbance was negatively associated with changes in myogenic enzymes (P < or = 0.032). Our results suggest that intense exercise during training camps for female judoists leads to the appearance and accumulation of mental and physical fatigue, which are related to each other.  相似文献   
26.
Abstract

The purpose of this study was to investigate Japanese elementary teachers’ professional development experiences in physical education in Japan. Participants were nine teachers from four public elementary schools. Data sources included semi-structured face-to-face interviews and annual physical education professional development portfolios. Three themes emerged from the data analyses: (a) the importance of mentoring for teachers’ growth, (b) annual in-house physical education portfolios as a professional development tool, and (c) the dilemma of being an independent learner in collective culture. The findings suggest that having access to past portfolios developed by previous teachers helped the Japanese elementary teachers to conceptualize the contents of professional learning that facilitated their transitions when they changed their teaching settings. To continuously grow as a teacher, they need to become independent learners who can make decisions about their instruction, identify the weaknesses of their instruction, and understand the impact of their pedagogy on their students’ learning.  相似文献   
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Gene ontology (GO) consists of three structured controlled vocabularies, i.e., GO domains, developed for describing attributes of gene products, and its annotation is crucial to provide a common gateway to access different model organism databases. This paper explores an effective application of text categorization methods to this highly practical problem in biology. As a first step, we attempt to tackle the automatic GO annotation task posed in the Text Retrieval Conference (TREC) 2004 Genomics Track. Given a pair of genes and an article reference where the genes appear, the task simulates assigning GO domain codes. We approach the problem with careful consideration of the specialized terminology and pay special attention to various forms of gene synonyms, so as to exhaustively locate the occurrences of the target gene. We extract the words around the spotted gene occurrences and used them to represent the gene for GO domain code annotation. We regard the task as a text categorization problem and adopt a variant of kNN with supervised term weighting schemes, making our method among the top-performing systems in the TREC official evaluation. Furthermore, we investigate different feature selection policies in conjunction with the treatment of terms associated with negative instances. Our experiments reveal that round-robin feature space allocation with eliminating negative terms substantially improves performance as GO terms become specific.  相似文献   
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This study examined ageing and free-living daily physical activity effects on salivary human beta-defensin 2 (hBD2). A total of 168 healthy elderly and 26 healthy young volunteers underwent saliva sampling. Free-living step count, energy expenditure and activity durations at specific intensity levels (inactive, light, moderate and vigorous) were evaluated. The results show significantly lower salivary hBD2 secretion rates for elderly than for young participants (P < 0.05). Data from elderly participants were stratified by steps per day using quartiles (Q1–Q4) for distribution. Elderly in quartiles respectively showed step counts of 3145 ± 129 in Q1, 5294 ± 83 in Q2, 7001 ± 86 in Q3 and 10,236 ± 416 steps · day?1 in Q4. In elderly participants, significant differences were found in the mean step count, energy expenditure and activity duration with increasing pedometer-determined activity quartiles. hBD2 secretion rates were significantly higher for Q2, Q3 and Q4 than for Q1 (P < 0.05). Elderly participants in Q3 had the highest hBD2 secretion. In conclusion, these results suggest that moderate physical activity in daily living improves age-related impairment of oral immune function mediated by hBD2. For oral immune function enhancement and for prevention of upper respiratory tract infections in elderly people, we recommend accumulation of more than 7000 steps · day?1.  相似文献   
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