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61.
62.
Abstract: The current generation of students coming into food science and engineering programs is very visually oriented from their early experiences. To increase their interest in learning, new and visually appealing teaching materials need to be developed. Two diverse groups of students may be identified based on their math skills. Food science students tend to find it difficult to use mathematics as a problem‐solving tool for food engineering problems. Food engineering students, on the other hand, should be challenged to use emerging mathematical tools to develop their problem‐solving skills. Therefore, the approach of this project involved the development of a curriculum to train undergraduate food engineers in the effective use of computational fluid dynamics (CFD) software to solve food engineering problems by engaging them in the creation of food engineering teaching tools. These CFD outputs were then used as innovative teaching tools for the food science students. In this paper, this concept will be illustrated by unsteady‐state heat transfer and fluid flow problems. To evaluate the efficiency of the teaching materials developed, a student focus group was asked to answer the same quiz following a conventional and CFD output aided teaching session. The assessment result showed an improved understanding of the subject after the CFD teaching session. These visual aids were excellent tools to illustrate the validity of the formulas presented in class. In addition, the new visual materials enabled a better understanding of the relationships among different process parameters. In general, this helped the food science students better appreciate the food engineering concepts that govern food processing operations. 相似文献
63.
J. W. Whitlow 《Learning & behavior》2010,38(2):145-159
The importance of configural cues and whether a situation involves beneficent or maleficent outcomes was investigated in two experiments on human causal reasoning, based on experienced causal information. Participants learned positive and negative patterning discriminations involving either beneficent or maleficent outcomes in a health-reasoning task and in a social-reasoning task. With maleficent outcomes, positive patterning was consistently easier to learn than negative patterning, a positive patterning advantage that is predicted by current associative theories and commonly taken as evidence for configural cues. However, with beneficent outcomes, the two discrimination tasks were not significantly different in ease of learning, a result not predicted by current theories. The reliable positive patterning effect found with maleficent outcomes broadens the range of conditions in which the effect can be shown in causal reasoning. The novel effect of outcome valence poses an interesting theoretical challenge for attempts to account for the relation between learning about individual cues and combinations of those cues. 相似文献
64.
Michael Dixon Pamela Beveridge Charlotte Farrior Beth Ann Williams William Sugar Abbie Brown 《TechTrends》2012,56(6):44-48
Four graduate students were tasked with creating a real-world solution to a problem faced by the instructional technology masters program in which they were participating. While taking an online course in multimedia instructional product development, part of East Carolina University??s Masters of Science in Instructional Technology degree program, a team of students faced the challenges of being physically separated, lacking some software and hardware tools, and the relatively brief development period of a semester??s time, to produce supplemental instructional content for students new to the masters program. Working from locations scattered throughout North Carolina, the production team found the time and resources, and relied on the strengths of individual team members, to produce an online orientation for students new to the instructional technology masters program. 相似文献
65.
Collective efficacy is an important determinant of the motivation of individuals within groups, with increases in collective efficacy producing more effort in a task and greater persistence when faced with failure. To test hypotheses concerning the impact of collective efficacy on effort and persistence, participants (n = 22) were assigned to triads (consisting of the participant and two confederates) and performed three time trials on cycle ergometers. After trial 1, the participants were assigned to either a high or low collective efficacy condition, receiving appropriate bogus performance feedback. All groups received failure feedback after trial 2. Effort was assessed by performance time and maximum heart rate (HRmax) achieved during performance. A 2 (collective efficacy condition) x 3 (trials) analysis of variance with repeated measures on trials revealed significant interaction effects for both performance time and HRmax. Fisher's least significant difference post-hoc tests indicated that, following efficacy manipulation, groups low in collective efficacy significantly reduced both their performance time and HRmax, whereas groups high in collective efficacy maintained performance and HRmax. However, predictions concerning the impact of failure on persistence were not supported. Our results provide partial support for the role of collective efficacy in team sports. 相似文献
66.
Increasing sport participation has been identified as a key vehicle for achieving World Health Organisation guidelines for health-enhancing physical activity (HEPA). A policy challenge is to promote this changed behaviour. Making use of the Active People Survey, a zero-inflated ordered probit model is used to identify the covariates of sport participation for males and females with respect to the related decisions to either participate in sport or not, and to participate at either lower or higher than desired intensity. To inform current policy emphases, the Active Places Survey is also used to examine the causal impact of facility provision on these behaviours. Results indicate that females are more likely to adopt less intensive activity even with time available. Families could place most constraints on females, but also reduce the intensity of male participation. Education has a greater association with higher intensity female activity. The largest effects are identified for sport club membership and facility satisfaction. Both of these affect male intensity of activity most. The main policy challenges facing sport in contributing to HEPA are shown to involve retaining male intensity of participation when ageing and encouraging greater female intensity of participation, with more appropriate matching of facilities. 相似文献
67.
Irene R. Faber Maria W. G. Nijhuis-Van Der Sanden Marije T. Elferink-Gemser Frits G. J. Oosterveld 《Journal of sports sciences》2015,33(11):1149-1158
A motor skills assessment could be helpful in talent development by estimating essential perceptuo-motor skills of young players, which are considered requisite to develop excellent technical and tactical qualities. The Netherlands Table Tennis Association uses a motor skills assessment in their talent development programme consisting of eight items measuring perceptuo-motor skills specific to table tennis under varying conditions. This study aimed to investigate this assessment regarding its reproducibility, internal consistency, underlying dimensions and concurrent validity in 113 young table tennis players (6–10 years). Intraclass correlation coefficients of six test items met the criteria of 0.7 with coefficients of variation between 3% and 8%. Cronbach’s alpha valued 0.853 for internal consistency. The principal components analysis distinguished two conceptually meaningful factors: “ball control” and “gross motor function.” Concurrent validity analyses demonstrated moderate associations between the motor skills assessment’s results and national ranking; boys r = ?0.53 (P < 0.001) and girls r = ?0.45 (P = 0.015). In conclusion, this evaluation demonstrated six test items with acceptable reproducibility, good internal consistency and good prospects for validity. Two test items need revision to upgrade reproducibility. Since the motor skills assessment seems to be a reproducible, objective part of a talent development programme, more longitudinal studies are required to investigate its predictive validity. 相似文献
68.
Paul T. Cutrufello Stephen J. Gadomski Gerald S. Zavorsky 《Journal of sports sciences》2015,33(14):1459-1466
Citrulline has been proposed as an ergogenic aid, leading to an interest in watermelon given its high citrulline concentration. The aim of this study was to determine the effects of a single, pre-exercise dose of l-citrulline, watermelon juice, or a placebo on the total maximum number of repetitions completed over 5 sets, time to exhaustion, maximal oxygen consumption (VO2max), anaerobic threshold, and flow-mediated vasodilation. A randomised double-blind within-participants study design was used to examine these effects among 22 participants (n = 11 males). Supplementation included either a 7.5% sucrose drink containing 6 g of l-citrulline, 710 mL of watermelon juice (~1.0 g citrulline), or a 7.5% sucrose placebo drink. Supplementation was administered 1 or 2 h before exercise testing to investigate a timing effect. There was no significant effect between the three supplements for the total number of repetitions, time to exhaustion, VO2max, anaerobic threshold, or flow-mediated vasodilation. There was also no interaction observed relative to gender or supplement timing (P > 0.05). A single dose of l-citrulline or watermelon juice as a pre-exercise supplement appears to be ineffective in improving exercise performance; however, greater doses of l-citrulline have been shown to be safe and are currently left unexamined. 相似文献
69.
Thomas G. Martin Rachel W. Pata Johanna D’Addario Lauren Yuknis Rebecca Kingston Richard Feinn 《Journal of sports sciences》2015,33(19):1988-1997
This study investigated whether haematological markers differ between young and masters marathon participants, running at similar performance levels. Nine young (31.89 ± 4.96 years) and eight masters (63.13 ± 4.61 years) runners participated. At five time points (pre-race through 54 h post-race), a complete blood cell count, basic metabolic panel and creatine kinase (CK) isoenzyme panel were assessed. Race performance was standardised using the World Masters Association Age Grading Performance Tables. Total CK levels were elevated for all participants at all time points post-race (P < 0.001). The CK-isoenzyme MB% was elevated across groups at 6, 30 and 54 h post-race (P < 0.01, P < 0.01 and P < 0.05), with masters runners having a higher CK-MB% at 30 and 54 h (P < 0.05, P < 0.05). Total white blood cell and neutrophil counts were elevated through 6 h post-race (P < 0.001), with higher levels found in younger runners (P < 0.001). When considering all blood work, masters runners had a higher number of abnormal values at 6, 30 and 54 h post-race (P < 0.05, P < 0.01 and P < 0.05). In conclusion, masters runners demonstrated sustained CK-MB elevation, which may suggest greater cardiac stress. However, future studies using additional cardiac markers should be completed to confirm these findings. In addition, masters runners showed an increased number of laboratory values outside normal range, indicating the body’s reduced capacity to respond to marathon running. 相似文献
70.