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51.
The Brisbane Media Map is both an online resource and a tertiary-level authentic learning project. The Brisbane Media Map is an online database which provides a detailed overview of about 600 media industry organizations in Brisbane, Australia. In addition to providing contact details and synopses for each organization’s profile, the Brisbane Media Map also includes supplementary information on current issues, trends, and individuals in the media and communication industry sectors. This resource is produced and updated annually by final-year undergraduate Media and Communication students. This article introduces the Brisbane Media Map, its functionality and systems design approach, as well as its alignment with key learning infrastructures. It examines authentic learning as the pedagogical framework underpinning the ongoing development work of the resource and highlights some synergies of this framework with participatory design principles. The Brisbane Media Map is a useful example of an authentic learning approach that successfully engages students of non-traditional and non-design areas of study in human–computer interaction, usability, and participatory design activities.  相似文献   
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Purpose: To evaluate the influence of physical maturity on the changes in ventricular morphology and function with sport training in female youth athletes.

Methods: Thirty-two female athletes (age 13–18 years) underwent height and weight measurement and 2-D echocardiographic evaluation immediately prior to, and following, a 20-week soccer season. Pre- and post-season left ventricular end-diastolic diameter (LVEDD), end-diastolic volume (LVEDV), ejection fraction (LVEF), stroke volume (LVSV), mass (LVM), and posterior wall thickness (LVPWT), right ventricular end-diastolic diameter (RVEDD), end-diastolic area (RVEDA), and fractional area change (RVFAC), and interventricular septal thickness (IVST) were compared. In-season change in each variable was compared across pre-season hours of vigorous physical activity (0–1, 2–3, >3 hours).

Results: Significant increases were identified in LVEDV (51.3?±?10.4?v 56.4?±?9.6?ml/m2, p?=?0.001) and RVEDA (10.5?±?1.9?v 11.3?±?2.5?cm2/m2, p?=?0.040), but not LVEDD, LVM, LVPWT, LVSV, RVEDD, RVEDA, RVFAC, or IVST (p?>?0.05 for all). In-season changes in echocardiographic variables did not differ across hours of pre-season vigorous physical activity (p?>?0.05 for all).

Conclusion: Among female adolescent soccer players, in-season training elicits changes in resting ventricular volume, but not wall thickness or systolic function. These adaptations do not appear to be influenced by pre-season physical activity level.  相似文献   
54.
Laceration injuries account for up to 23% of injuries in rugby union. They are frequently caused by studded footwear as a result of a player stamping onto another player during the ruck. Little is known about the kinetics and kinematics of rugby stamping impacts; current test methods assessing laceration injury risk of stud designs therefore lack informed test parameters. In this study, twelve participants stamped on an anthropomorphic test device in a one-on-one simulated ruck setting. Velocity and inclination angle of the foot prior to impact was determined from high-speed video footage. Total stamping force and individual stud force were measured using pressure sensors. Mean foot inbound velocity was 4.3 m ? s?1 (range 2.1–6.3 m ? s?1). Mean peak total force was 1246 N and mean peak stud force was 214 N. The total mean effective mass during stamping was 6.6 kg (range: 1.6–13.5 kg) and stud effective mass was 1.2 kg (range: 0.5–2.9 kg). These results provide representative test parameters for mechanical test devices designed to assess laceration injury risk of studded footwear for rugby union.  相似文献   
55.
Abstract

Though clinical observations and laboratory data provide some support for the neuromuscular imbalance theory of the genesis of exercise-associated muscle cramps, no direct evidence has been published. The purpose of this study was to determine the effect of local muscle fatigue on the threshold frequency of an electrically induced muscle cramp. To determine baseline threshold frequency, a cramp was electrically induced in the flexor hallucis brevis of 16 apparently healthy participants (7 males, 9 females; age 25.1 ± 4.8 years). The testing order of control and fatigue conditions was counterbalanced. In the control condition, participants rested in a supine position for 30 min followed by another cramp induction to determine post-threshold frequency. In the fatigue condition, participants performed five bouts of great toe curls at 60% one-repetition maximum to failure with 1 min rest between bouts followed immediately by a post-threshold frequency measurement. Repeated-measures analysis of variance and simple main effects testing showed post-fatigue threshold frequency (32.9 ± 11.7 Hz) was greater (P < 0.001) than pre-fatigue threshold frequency (20.0 ± 7.7 Hz). An increase in threshold frequency seems to demonstrate a decrease in one's propensity to cramp following the fatigue exercise regimen used. These results contradict the proposed theory that suggests cramp propensity should increase following fatigue. However, differences in laboratory versus clinical fatiguing exercise and contributions from other sources, as well as the notion of a graded response to fatiguing exercise, on exercise-associated muscle cramp and electrically induced muscle cramp should be considered.  相似文献   
56.
Abstract

The purpose of this investigation was to examine the effects of cluster set configurations on power clean technique. Ten male, recreational weightlifters performed three sets of six repetitions at 80% of one repetition max with 0 (P0), 20 (P20) or 40 seconds (P40) inter-repetition rest. During the first and second set of P0, the catch and first pull were in a more forward position during repetition 6 as compared to repetition 1, respectively. During the second set of P40, differences in horizontal displacement were found between repetitions 1 and 6 for the second pull and the loop. During the third set of P40, differences in horizontal displacement were found between repetitions 1 and 6 for the first pull, transition, and beginning of the second pull. No differences in horizontal displacement were found between repetitions 1 and 6 during P20. During each set of P0, vertical displacement decreased between repetitions 1 and 6 (1.02 ± 0.07 m vs. 0.94 ± 0.06 m; Mean ± s). Cluster set configurations led to the maintenance of vertical displacement throughout all sets. The results demonstrate cluster set configurations with greater than 20 seconds inter-repetition rest maintain weightlifting technique to a greater extent than a traditional set configuration.  相似文献   
57.
Despite the significant role of radical innovation as a driver of firm growth and performance, the consequences of resource constraints for radical innovation outcomes remain unknown. Our paper addresses this gap. We combine arguments from entrepreneurship theory and the theory of recombinative innovation to construct an overarching theoretical framework that argues why resource constraints can promote, rather than impede, radical innovation. We then build hypotheses on two specific resource constraints, knowledge and financial, and test these by a lagged-variable random-effects Tobit model with longitudinal data from an exceptionally large and detailed innovation survey. Controlling for absorptive capacity, firm age, and firm growth, we find full support for the hypothesis that knowledge constraints spur radical innovation and partial support for the hypothesis that financial constraints spur radical innovation. We discuss the theoretical significance of these findings and point to managerial implications and paths for future research.  相似文献   
58.
This paper describes the use of learning-hierarchy analysis in studies of expertise. A hierarchical analysis was carried out on expertise in language-arts teacher planning for a short story. The resulting hierarchy depicted a complex pattern of prerequisite intellectual skills integrating knowledge of students, reading difficulty, strategies/activities, and the author (Stephen Crane). Of particular interest was that each branch of the hierarchy included “fuzzy sets,” that is, complex conceptual knowledge that experts were usually unable to explain. All elements in the hierarchy were capabilities learned from experience as opposed to direct instruction. It was recommended that advice-strategies developed from hierarchical analysis could be used to facilitate the development of expertise. These strategies do not teach expertise directly but encourage the learner to glean the most from task-relevant experience.  相似文献   
59.
A major concern about the effects of day care has been the safety of the children who participate. Although studies are limited, a body of research literature is beginning to emerge that provides some important information about the magnitude of accidental injuries in day care centers.Charles W. Snow is Professor and Jane King Teleki is Associate Professor, Department of Child Development and Family Relations; David M. Cline is Assistant Professor, Department of Emergency Medicine; and Kathleen Dunn is Clinical Instructor, Department of Preventive Medicine and Public Health Policy, East Carolina University, Greenville, NC.  相似文献   
60.
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