Gender differences among sagittal plane knee kinematic and ground reaction force characteristics during a rapid sprint and cut maneuver

Women are more prone to anterior cruciate ligament (ACL) injury during cutting sports than men. The purpose of this study was to examine knee kinematic and ground reaction forces (GRF) differences between genders during cutting. Male and female athletes performed cutting trials while force platform and video data were recorded (180 Hz). Differences (p < . 05) were observed between groups for knee flexion at contact and GRF at maximum knee flexion. Women averaged 5.8 degrees less flexion at contact and 1.0 N. (kg x m x s(-1))(-1) greater GRF at maximum flexion. Knee range of motion and peak GRF variables were not significantly different, but women had greater values. Women exhibited technique characteristics believed to increase ACL injury risk, but men exhibiting similar characteristics were also observed and could also be at risk.     

Analysis of postural stability in collegiate soccer players before and after an acute bout of heading multiple soccer balls

The aim of our study was to determine if any immediate changes in balance were discernable in college soccer players after a specially designed heading session. Eight male and two female skilled collegiate soccer players had a baseline balance pre-test using the Balance Master, followed by heading 20 balls kicked consecutively by a teammate from the touchline to a point near the goal, which was followed by a post-test using the same testing technique. Paired t-tests were used to compare balance ability between pre- and post-test conditions. There was no difference in balance pre- to post-test (85.3% and 86.2% respectively). No significant difference was noted from pre- to post-test in the mean equilibrium scores for conditions three through six on the Sensory Organization Test, with the exception of condition four, which revealed a significant increase from pre- to post-test. We concluded that an acute session of heading soccer balls may not result in balance changes in collegiate soccer players.     

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��[Purpose/significance] Under the background of open innovation, the market competition of platform enterprises is becoming more and more fierce, the platform homogeneity is serious, the user flow is drying up day by day, and the growth is difficult. The lack of innovation resources and capability in the platform enterprises can't effectively support the business model innovation of enterprises. In this context, boundary-spanning search and big data capability construction provide a strong support for business model innovation of platform enterprises.[Method/process] Through literature related to boundary-spanning search, big data capability and business model innovation was review.Based on the elements of business model of platform enterprises, a synergistic model of boundary-spanning search and big data capability was constructed.[Result/conclusion] Boundary-spanning search is helpful to innovative knowledge flow and obtain innovative resources. Big data capability can complete resource integration and analysis in-depth. The synergistic effect of the two can promote the discovery of new knowledge in the market and facilitate the innovation of business model of platform enterprises.     

Teaching general science through film production

Conclusion Differences in achievement under the two methods in the acquisition of information and in the ability to apply information to novel situations were in favor of the film-presentation method, and were large enough to be significant at the 2 and 5 percent levels of confidence respectively. Therefore, under the conditions of this experiment, joint pupil-teacher film production was not as effective in producing achievement in the learning outcomes measured as the film-presentation method. As regards retention of learning, the experimenter concluded that neither method was superior. It was also found that the film-production method was more costly, and that most pupils preferred it even though they did not always feel that they learned the most science by that method. How effective is the use of student film production for the teaching of content in a subject matter area? This study shows the superiority of conventional film presentation techniques over such joint pupil-teacher film production. Carlton W. H. Erickson is director of the audio-visual center and associate professor of education at the University of Connecticut. The article is based on a doctoral dissertation at the Boston University School of Education, entitled, “The Effectiveness of Joint Pupil-Teacher Motion Picture Production as a Method of Teaching General Science.”