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131.
Kevin King N. C. Perkins Hugh Churchill Ryan McGinnis Ryan Doss Ron Hickland 《Sports Engineering》2011,13(2):95-104
This paper presents a novel sensor technology to deduce the dynamics of a bowling ball. The sensor, a miniature wireless inertial
measurement unit (IMU), incorporates MEMS accelerometers and angular rate gyros, a microcontroller, a low power RF transceiver,
and a rechargeable battery. When embedded in a bowling ball, the IMU transmits the acceleration and angular velocity data
that define the dynamics of the ball starting with the bowler’s delivery and its motion in the lane. Example results from
professional bowlers illustrate how this technology can be used to assess bowler skill and ball performance. For instance,
the IMU accurately measures the spin dynamics of the ball which are crucial to develop the ball “hook.” An analysis of ball
dynamics in the lane is distilled to a measurable “hook potential” metric for further assessing bowler skill. Finally, the
sensor presented herein is believed to be the world’s smallest, wireless IMU. This highly miniaturized and wireless design
will enable parallel training systems for many sports, including basketball, baseball, crew, cricket, golf, fly fishing, soccer,
softball, tennis, rowing, among others. 相似文献
132.
The successful encapsulation of human hepatocellular carcinoma (HepG2) cells would greatly assist a broad range of applications in tissue engineering. Due to the harsh conditions during standard chitosan fiber fabrication processes, encapsulation of HepG2 cells in chitosan fibers has been challenging. Here, we describe the successful wet-spinning of chitosan-alginate fibers using a coaxial flow microfluidic chip. We determined the optimal mixing conditions for generating chitosan-alginate fibers, including a 1:5 ratio of 2% (w∕w) water-soluble chitosan (WSC) solution to 2% (w∕w) alginate solution. Ratio including higher than 2% (w∕w) WSC solution increased aggregation throughout the mixture. By suspending cells in the WSC-alginate solution, we successfully fabricated HepG2 cell-laden fibers. The encapsulated HepG2 cells in the chitosan-alginate fibers were more viable than cells encapsulated in pure alginate fibers, suggesting that cross-linked chitosan provides a better environment for HepG2 cells than alginate alone. In addition, we found that the adhesion of HepG2 cells on the chitosan-alginate fiber is much better than that on the alginate fibers. 相似文献
133.
In this article, the authors present the fabrication of an enzyme-entrapped alginate hollow fiber using a microfluidic device. Further use of enzyme-entrapped alginate hollow fibers as a biocatalytic microchemical reactor for chemical synthesis is also deliberated in this article. To ensure that there is no enzyme leaching from the fiber, fiber surfaces were coated with chitosan. To confine the mobility of reactants and products within the porous hollow fibers the entire fibers were embedded into a transparent polydimethylsiloxane (PDMS) matrix which also works as a support matrix. A vanadium-containing bromoperoxidase enzyme isolated from Corallina confusa was used as a model enzyme to demonstrate the use of these alginate hollow-fiber reactors in bromo-oxidation of phenol red to bromophenol blue at different dye flow rates. Stability of the entrapped enzyme at different temperatures and the effect of the chitosan coating on the reaction conversion were also studied. It was observed that molecules as big as 27 kDa can be retained in the matrix after coating with chitosan while molecules with molecular-weight of around 378 Da can still diffuse in and out of the matrix. The kinetic conversion rate in this microfluidic bioreactor was more than 41-fold faster when compared with the standard test-tube procedure. 相似文献
134.
When using a driver, the centre of pressure of a golfer shows a pattern that is characteristic of one of two distinct swing styles: the "front foot" style or the "reverse" style. The aim of this study was to establish whether these two swing styles are also evident when using other clubs, and if so, to determine whether golfers use the same swing style when using different clubs. Forty-six professional, amateur, and recreational golfers performed swings to hit a ball into a net placed 3 m away. Ten swings were performed for each of the driver, 3-iron, and 7-iron while standing on two force plates. The position of the golfer's centre of pressure parallel with the line of shot and relative to the feet was quantified at eight swing events that were identified from 200-Hz video. Cluster analysis confirmed that the front foot and reverse styles were evident in all three clubs, and most of the golfers (96%) used the same swing style for all three clubs. Golfers that used the reverse swing positioned their centre of pressure nearer to their toes at ball contact compared with golfers that used the front foot swing. 相似文献
135.
Ford P De Ste Croix M Lloyd R Meyers R Moosavi M Oliver J Till K Williams C 《Journal of sports sciences》2011,29(4):389-402
Within the UK, the "Long Term Athlete Development" (LTAD) model has been proposed by a variety of national governing bodies to offer a first step to considering the approach to talent development. The model, which is primarily a physiological perspective, presents an advancement of understanding of developing athletic potential alongside biological growth. It focuses on training to optimize performance longitudinally, and considers sensitive developmental periods known as "windows of opportunity". However, it appears that there are a number of problems with this theoretical model that are not necessarily transparent to coaches. Principally, the model is only one-dimensional, there is a lack of empirical evidence upon which the model is based, and interpretations of the model are restricted because the data on which it is based rely on questionable assumptions and erroneous methodologies. Fundamentally, this is a generic model rather than an individualized plan for athletes. It is crucial that the LTAD model is seen as a "work in progress" and the challenge, particularly for paediatric exercise scientists, is to question, test, and revise the model. It is unlikely that this can be accomplished using classical experimental research methodology but this should not deter practitioners from acquiring valid and reliable evidence. 相似文献
136.
Sarı Uğur Pektaş Hüseyin Miraç Şen Ömer Faruk Çelik Harun 《Education and Information Technologies》2022,27(5):6669-6689
Education and Information Technologies - The need to benefit from information technologies in the twenty-first century digital age is increasing in all economies to overcome problems and... 相似文献
137.
Juanita Gamez Vargas Rick Roach Kevin M. David 《Community College Journal of Research & Practice》2014,38(2-3):166-173
The article presents the implementation and findings of a successful collaborative effort with the Oklahoma State Regents for Higher Education (OSRHE), Tulsa Community College (TCC), and two local public school districts, Tulsa Public Schools (TPS) and Union Public Schools (UPS). Known as EXCELerate, it's a five-semester dual enrollment pilot program that received state policy exceptions for juniors and seniors to enroll in dual enrollment courses and supportive resources from the participating agencies. Whereas the traditional dual enrollment student is White and college-going, the program's intent was to increase the number of high school students who may be first-generation, lower-socioeconomic, ethnic or non-ethnic. The article identifies three major barriers to successful dual enrollment and completion: state policy, financial issues, and transportation. It also examines how these barriers were eliminated through a collaborative effort. The results demonstrate that over 87% of the juniors and seniors persisted over the semesters, and enrollment tripled among African American and Latino students. The article is constructed to benefit further research and practical application for urban and rural community colleges. 相似文献
138.
Donna Farland-Smith Kevin Finson William J. Boone Melissa Yale 《Journal of Science Teacher Education》2014,25(3):355-366
Even long before children are able to verbalize which careers may be interesting to them, they collect and store ideas about scientists. For these reasons, asking children to Draw-A-Scientist has become an accepted method to provide a glimpse into how children represent and identify with those in the science fields. Years later these representations may translate into student’s career choice. Since 1995, children’s illustrations of scientists have been assessed by the Draw-A-Scientist Checklist (DAST-C). The checklist was created from the common aspects or features found in illustrations from previous studies and were based initially on the scientists, broken down into “stereotypical” and “alternative” images shown in the drawings. The purpose of this paper is to describe the development, field test and reliability of the modified Draw-A-Scientist Test (DAST) and The Draw-A-Scientist Rubric designed as an improvement of the DAST-C to provide a more appropriate method of assessing students’ drawings of scientists. The combination of the modified DAST and the DAST Rubric brings more refinement as it enables clarities to emerge and subsequently increased detail to what one could ascertain from students about their mental images of scientists. 相似文献
139.
140.
Michelle D. Lazarus Gordon L. Kauffman Jr. Milind J. Kothari Timothy J. Mosher Matthew L. Silvis John R. Wawrzyniak Daniel T. Anderson Kevin P. Black 《Anatomical sciences education》2014,7(5):379-388
Current undergraduate medical school curricular trends focus on both vertical integration of clinical knowledge into the traditionally basic science‐dedicated curricula and increasing basic science education in the clinical years. This latter type of integration is more difficult and less reported on than the former. Here, we present an outline of a course wherein the primary learning and teaching objective is to integrate basic science anatomy knowledge with clinical education. The course was developed through collaboration by a multi‐specialist course development team (composed of both basic scientists and physicians) and was founded in current adult learning theories. The course was designed to be widely applicable to multiple future specialties, using current published reports regarding the topics and clinical care areas relying heavily on anatomical knowledge regardless of specialist focus. To this end, the course focuses on the role of anatomy in the diagnosis and treatment of frequently encountered musculoskeletal conditions. Our iterative implementation and action research approach to this course development has yielded a curricular template for anatomy integration into clinical years. Key components for successful implementation of these types of courses, including content topic sequence, the faculty development team, learning approaches, and hidden curricula, were developed. We also report preliminary feedback from course stakeholders and lessons learned through the process. The purpose of this report is to enhance the current literature regarding basic science integration in the clinical years of medical school. Anat Sci Educ 7: 379–388. © 2014 American Association of Anatomists. 相似文献