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排序方式: 共有762条查询结果,搜索用时 15 毫秒
41.
Taylor M. Weiskittel Nirusha Lachman Anjali Bhagra Kylie Andersen Jeff St. Jeor Wojciech Pawlina 《Anatomical sciences education》2021,14(3):377-384
The clinical use of ultrasound has dramatically increased, necessitating early ultrasound education and the development of new tools in ultrasound training and assessment. The goal of this study was to devise a novel low-resource examination that tested the anatomical knowledge and technical skill of early undergraduate medical students in a gross anatomy course. The team-based ultrasound objective structured practice examination (OSPE) was created as a method for assessing practical ultrasound competencies, anatomical knowledge, and non-technical skills such as teamwork and professionalism. The examination utilized a rotation of students through four team roles as they scanned different areas of the body. This station-based examination required four models and four instructors, and tested ultrasound skills in the heart, abdominal vessels, abdominal organs, and neck regions. A Likert scale survey assessed student attitudes toward the examination. Survey data from participants (n = 46) were examined along with OSPE examination grades (n = 52). Mean and standard deviations were calculated for examination items and survey responses. Student grades were high in both technical (96.5%). and professional (96.5%) competencies with structure identification scoring the lowest (93.8%). There were no statistical differences between performances in each of the body regions being scanned. The survey showed that students deemed the examination to be fair and effective. In addition, students agreed that the examination motivated them to practice ultrasound. The team-based OSPE was found to be an efficient and student-favored method for evaluating integrated ultrasound competencies, anatomical knowledge, team-work, and professional attributes. 相似文献
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AbstractA key element contributing to deteriorating exercise capacity during physically demanding sport appears to be reduced carbohydrate availability coupled with an inability to effectively utilize alternative lipid fuel sources. Paradoxically, cognitive and physical decline associated with glycogen depletion occurs in the presence of an over-abundance of fuel stored as body fat that the athlete is apparently unable to access effectively. Current fuelling tactics that emphasize high-carbohydrate intakes before and during exercise inhibit fat utilization. The most efficient approach to accelerate the body’s ability to oxidize fat is to lower dietary carbohydrate intake to a level that results in nutritional ketosis (i.e., circulating ketone levels >0.5 mmol/L) while increasing fat intake for a period of several weeks. The coordinated set of metabolic adaptations that ensures proper interorgan fuel supply in the face of low-carbohydrate availability is referred to as keto-adaptation. Beyond simply providing a stable source of fuel for the brain, the major circulating ketone body, beta-hydroxybutyrate, has recently been shown to act as a signalling molecule capable of altering gene expression, eliciting complementary effects of keto-adaptation that could extend human physical and mental performance beyond current expectation. In this paper, we review these new findings and propose that the shift to fatty acids and ketones as primary fuels when dietary carbohydrate is restricted could be of benefit for some athletes. 相似文献
44.
The University of North Texas (UNT) Libraries are funded almost entirely by undergraduate student use fees. As the undergraduate enrollment has plateaued in recent years, the libraries have not been able to keep up with rising costs, resulting in a series of cuts to the materials budget totaling around $3.25 million. While some of these cuts took the form of reductions in firm orders and dissolution of approval plans, for the past three years the bulk has come from cancellations of serials and electronic resources. With each year’s cuts, the UNT Collection Development department has been forced to modify and refine their deselection process. This article will show the development of UNT’s strategy for determining cancellations using a variety of methods (overlap analysis, usage statistics, faculty input) and tools (EBSCO Usage Consolidation, Serials Solutions 360). 相似文献
45.
Todd Colin Pataky 《Journal of sports sciences》2015,33(2):192-197
Disagreements exist in the literature regarding the manner in which weight should be dynamically shared during the golf swing, both within-feet and between the back- and target-foot, to generate maximal clubhead speed. The purpose of this study was to determine whether preferential foot-loading locations underlie weight sharing by examining the correlation between clubhead speed and maximum plantar pressure (PP) distributions. Thirty-two amateur golfers with handicap indexes ranging from 2.7 to 25 performed 10 driver swings on artificial turf following a warm-up. PP distributions were recorded at 100 Hz, and clubhead speed was recorded using a ball-tracking Doppler radar system. Maximum PPs were extracted from a 2-s window approximately centred on ball contact and were regressed against clubhead speed. Significance was assessed over the entire foot surface using statistical parametric mapping (SPM), a spatially continuous technique. SPM revealed, at relatively high anatomical resolution, significant positive correlations between clubhead speed and PPs in the lateral target-foot (P < 0.05). This suggests that not only weight transfer but also weight-transfer location may be an important determinant of clubhead speed in amateur golfers. 相似文献
46.
As the number of reference questions continues to decline across academic libraries, innovative models have been developed to highlight collections and reach underserved communities. This article describes four outreach models at the University of New Mexico University Libraries, including satellite outreach services, pop-up book trucks and events, and relationship building at various locations on and off campus. The authors describe innovative approaches including curated browsing experiences and relationship marketing to underserved communities. Lessons learned, future approaches, and the benefits of each model will also be explored. 相似文献
47.
Many formal policies have suggested that officers need a college degree; however, policies forced little change in practices of American police organizations. Six hundred-fifty patrol officers employed in 12 medium-sized police departments in three Midwestern states were surveyed as to their current educational attainment and job performance. The purpose of this study was to determine the relationship between educational level and police performance. 相似文献
48.
Campbell Todd Longhurst Max L. Wang Shiang-Kwei Hsu Hui-Yin Coster Dan C. 《Journal of Science Education and Technology》2015,24(5):562-579
Journal of Science Education and Technology - While access to computers, other technologies, and cyber-enabled resources that could be leveraged for enhancing student learning in science is... 相似文献
49.
Field and laboratory measurements of softball player swing speed and bat performance 总被引:1,自引:1,他引:0
The swing speed of the bat is one of the most important factors affecting the hit-ball speed. Most field studies tend to focus on measuring ball speed, which is easier to measure and quantify than bat speed. For this reason, relatively little data exist describing bat motion in field conditions. The following describes a relatively large swing speed field study involving bats of the same model with nearly constant weight and varying inertia. The study was conducted using right-handed batters on a regulation outdoor field with a live pitcher. Swing speed was measured by tracking markers on the bat with two high-speed video cameras so that the bat markers could be traced in three-dimensional space. The ball motion was tracked using the same high-speed video cameras and a three-dimensional Doppler radar system. Bat swing speed was observed to be proportional to the batter skill level and the normalised swing speed increased with decreasing bat inertia. The bat centre of rotation during impact was close to the knob of the bat. The bats were tested under controlled laboratory conditions using a standardised performance test. The field and laboratory results showed good agreement including the hit-ball speed and the subtle effect of bat inertia on the maximum performance location. The vibrational response of the bats was considered using modal analysis. The maximum performance location was correlated with the node of the first vibrational mode. 相似文献
50.