Does performance level affect initial ball flight kinematics in finger and wrist-spin cricket bowlers?

Spin bowling plays a fundamental role within the game of cricket yet little is known about the initial ball kinematics in elite and pathway spin bowlers or their relationship to performance. Therefore, the purpose of this study was to record three-dimensional ball kinematics in a large and truly high level cohort of elite and pathway finger-spin (FS) and wrist-spin (WS) bowlers, identifying potential performance measures that can be subsequently used in future research. A 22-camera Vicon motion analysis system captured retro-reflective markers placed on the seam (static) and ball (dynamic) to quantify ball kinematics in 36 FS (12 elite and 24 pathway) and 20 WS (eight elite and 12 pathway) bowlers. Results indicated that FS bowlers delivered the ball with an increased axis of rotation elevation, while wrist-spin bowlers placed greater amounts of revolutions on the ball. It also highlighted that ball release (BR) velocity, revolutions and velocity/revolution index scores for both groups and seam stability for FS bowlers, and seam azimuth angle and spin axis elevation angle for WS bowlers, were discriminators of playing level. As such these variables could be used as indicators of performance (i.e. performance measures) in future research.     

Digital and analog logics: An analysis of the discourse on property rights and information goods

We examine arguments both for strengthening property rights and expanding the public domain for digital information goods. Specifically, we conduct a Toulminian analysis of arguments made at a cross-disciplinary symposium at Duke Law School on information goods and the public domain. We find that there are two “logics” underlying arguments on issues related to information goods: what we describe as digital and analog logics. We also identify five argument categories—profit motive, economic efficiency, innovation, ethics and fundamental rights, and temporality—and two different time frames used for judging impacts—proximal and distal. We conclude with a number of theory-generating propositions and a provocation for our conceptions of capitalism in the digital age.     

Relationships among creativity,intelligence, and achievement measures in upward bound students

Ninety-four disadvantaged, Upward Bound students were administered a test battery of the Otis Quick-Scoring Mental Ability Test, Preliminary Scholastic Aptitude Test, Guilford's tests of Expressional Fluency, Alternate Uses, and Consequences; and the Figural Form of the Torrance Tests of Creative Thinking. Significant sex differences favoring males were obtained for Otis I J(P < −025), PSAT-Verbal (p <.01), and PSAT-Quantitative (p <.001). Females excelled males on the figural elaboration score from the TTCT (p <.001). White disadvantaged students scored significantly higher than their Indian counterparts on Otis IQ (p <.05) and higher than their black counterparts on the PSAT-Quantitative (p <.01). White students also scored significantly higher than their Indian counterparts on Guilford-Consequences — Obvious (p <.05). A varimax rotation of the correlation matrix resulted in a two-factor solution defined by intelligence-achievement scores and figural creativity. Guilford creativity tests were more closely related to the intelligence-achievement factor, while the Torrance figural creativity test remained a distinct factor. The results are discussed in relation to previous studies of the creativity-intelligence distinction.     

An incremental approach to implementing a web course

Conclusion Our premise, that involvement with Web-based instruction proceeds best incrementally, has been explored in a variety of examples. A range of options, as well as a strategy for dealing with them systematically, has been presented. Our four-step model, adapted from an earlier one by DeBloois & Alder (1973), has four levels: awareness, faculty support, faculty skills, and departmental effort. Practitioners in higher education in the 21st Century will need to capitalize on creative ways to build Web resources, used one at a time, into existing courses, leading to enhanced learning opportunities for students and faculty alike     

Muscle co-activation and its influence on running performance and risk of injury in elite Kenyan runners

The relationship between muscle co-activation and energy cost of transport and risk of injury (initial loading rate and joint stiffness) has not been jointly studied. Fourteen elite Kenyan male runners were tested at two speeds (12 and 20 km · h^?1), where oxygen consumption, kinematic, kinetic and electromyography were recorded. Electromyography of seven lower limb muscles was recorded. Pre-activation and ground contact of agonist:antagonist co-activation was determined. All muscles displayed higher activity during pre-activation except rectus femoris (RF). Conversely, no differences were found during ground contact except for higher biceps femoris (BF) at 20 km · h^?1. Knee stiffness was correlated to RF–BF co-activation during both pre-activation and ground contact at both running speeds. However, energy cost of transport was only positively correlated to the above-mentioned muscle pairs at 20 km · h^?1 (r = 0620, P = 0.032; r = 0.682, P = 0.015, respectively). These findings emphasise the influence of neuromuscular control and performance and its support to musculoskeletal system to optimise function and modulate risk of injury. Further, neuromuscular activity during terminal swing is also important and necessary to execute and maintain performance.     

Student-Created Curricular and Co-Curricular Pathways Toward Participation in a Diverse Democracy

This study explored the ways in which undergraduate students intentionally navigate complex curricular and co-curricular choices in preparation for engaging in a diverse democracy. Our study examined these choices among students at a university that lacks formal structures to facilitate these choices. Four curricular and co-curricular pathways that exemplify particular forms of the student experience across disciplines emerged and are discussed.     

Optimization of oar blade design for improved performance in rowing

The aim of the present study was to find a more optimal blade design for rowing performance than the Big Blade, which has been shown to be less than optimal for propulsion. As well as the Big Blade, a flat Big Blade, a flat rectangular blade, and a rectangular blade with the same curvature and projected area as the Big Blade were tested in a water flume to determine their fluid dynamic characteristics at the full range of angles at which the oar blade might present itself to the water. Similarities were observed between the flat Big Blade and rectangular blades. However, the curved rectangular blade generated significantly more lift in the angle range 0-90 degrees than the curved Big Blade, although it was similar between 90 and 180 degrees. This difference was attributed to the shape of the upper and lower edges of the blade and their influence on the fluid flow around the blade. Although the influence of oar blade design on boat speed was not investigated here, the significant increases in fluid force coefficients for the curved rectangular blade suggest that this new oar blade design could elicit a practically significant improvement in rowing performance.     

Using the cumulative common log-odds ratio to identify differential item functioning of rating scale items in the exercise and sport sciences

One aspect of construct validity is the extent to which the measurement properties of a rating scale are invariant across the groups being compared. An increasingly used method for assessing between-group differences in the measurement properties of items of a scale is the framework of differential item functioning (DIF). In this paper we introduce the concept of DIF as a validation tool for scales used in physical education and exercise science, and illustrate the use of the cumulative common log-odds ratio for assessing the presence of DIF with data from the Exercise Imagery Inventory (EII; Giacobbi, Hausenblas, & Penfield, 2005).