Development and optimization of an injury prevention intervention for physical education teachers

Background: Injury prevention is highly needed in physically active populations, such as pre-service and in-service physical education teachers (PETs). As a lack of adherence to preventive strategies is problematic in injury, it seems crucial to develop and optimize interventions that correspond to the specific needs and wishes of PETs.

Aim: The purpose of the present study was fourfold. Specifically, we aimed at (1) systematically optimizing an injury prevention intervention for PETs, based on teachers’ qualitative evaluation of the intervention, (2) quantitatively investigating whether the appreciation of the injury prevention intervention was higher after optimization, (3) examining whether participation in the intervention resulted in positive changes in teachers’ perceived utility of, and confidence to apply the proposed preventive strategies, as well as their knowledge about these strategies, and (4) describing teachers’ adherence to the proposed preventive strategies while they were engaging in the intervention.

Participants: Twenty PETs (13 men, Mage = 42.1 ± 12.17 years) from nine different secondary schools in Flanders (Belgium) voluntarily participated in this study. The intervention, based on findings from the continuing professional development (CPD) literature, and the principles of the self-determination theory, took place on two different training days (Training A and Training B) and consisted of seven intrinsic injury prevention strategies.

Data collection and analysis: Qualitative data on teachers’ appreciation of the intervention were collected by means of focus group interviews, which were used to optimize the intervention (Aim 1). Quantitative data on teachers’ appreciation were collected directly after they had engaged in the intervention and were used to compare the appreciation from the initial to more optimized versions of the trainings (Aim 2). Further, by means of repeated measures ANOVAs positive evolutions in teachers’ belief in the utility of, confidence to apply and knowledge about the provided strategies across time were examined (Aim 3). Finally, teachers’ adherence was evaluated by relying on weekly online registrations of minutes and types of preventive strategies teachers had practised during the past week (Aim 4).

Findings: Despite the relatively high initial appreciation scores (4.2 out of 5), the optimized versions of the trainings scored better on interaction, intelligibility, innovation, practical usefulness, and recommendation (Aims 1 and 2). Significant differences were found over time in terms of within-teacher changes in perceived utility of (4.05–4.73–4.48; p?p?p?Conclusions: The present study developed an intervention that optimally fulfils the wishes and needs of the target population, namely PETs, and can readily be implemented in PET education programmes or CPD programmes for in-service PETs. Results of this pilot study are promising because teachers displayed increases in several relevant outcomes. Various suggestions are formulated on how to increase PETs’ appreciation of CPD programmes.     

Retracted publications in pharmacy systematic reviews

Objective:Systematic reviews and other evidence syntheses, the pinnacle of the evidence pyramid, embody comprehensiveness and rigor; however, retracted data are being incorporated into these publications. This study examines the use of retracted publications in the field of pharmacy, describes characteristics of retracted publications cited by systematic reviews, and discusses factors associated with citation likelihood.Methods:Using data from Retraction Watch, we identified retracted publications in the pharmacy field. We identified all articles citing these retracted publications in Web of Science and Scopus and limited results to systematic reviews. We classified the retraction reason, determined whether the citation occurred before or after retraction, and analyzed factors associated with the likelihood of systematic reviews citing a retracted publication.Results:Of 1,396 retracted publications, 283 were cited 1,096 times in systematic reviews. Most (65.0%) (712/1096) citations occurred before retraction. Citations were most often to items retracted due to data falsification or manipulation (39.2%), followed by items retracted due to ethical misconduct including plagiarism (30.4%), or concerns about or errors in data or methods (26.2%). Compared to those not cited in systematic reviews, cited items were significantly more likely to be retracted due to data falsification and manipulation, were published in high impact factor journals, and had longer delays between publication and retraction.Conclusions:Further analysis of systematic reviews citing retracted publications is needed to determine the impact of flawed data. Librarians understand the nuances involved and can advocate for greater transparency around the retraction process and increase awareness of challenges posed by retractions.     

Sample preconcentration inside sessile droplets using electrowetting

Electrowetting with alternate voltage (AC) creates azimuthal flow vortices inside sessile droplets. These flow vortices can be controlled by introducing pinning sites at the contact line. When the frequency of the applied AC voltage is gradually ramped from a few hundreds of hertz to a few tens of kilohertz the azimuthal flow vortices contract and move towards the contact line near the pinning site. Dispersed particles in the liquid are collected in the center of these vortices leading to an increase in the local particle concentration by up to more than one order of magnitude. We provide a qualitative explanation for symmetry of the flow patterns within the drops and discuss possible scenarios explaining the particle collection and preconcentration.     

Joint power generation differentiates young and adult sprinters during the transition from block start into acceleration: a cross-sectional study

The aim of this study was to investigate differences in joint power generation between well-trained adult athletes and young sprinters from block clearance to initial contact of second stance. Eleven under 16 (U16) and 18 under 18 (U18) promising sprinters executed an explosive start action. Fourteen well-trained adult sprinters completed the exact same protocol. All athletes were equipped with 74 spherical reflective markers, while an opto-electronic motion analysis system consisting of 12 infrared cameras (250 Hz, MX3, Vicon, Oxford Metrics, UK) and 2 Kistler force plates (1,000 Hz) was used to collect the three-dimensional marker trajectories and ground reaction forces (Nexus, Vicon). Three-dimensional kinematics, kinetics, and power were calculated (Opensim) and time normalised from the first action after gunshot until initial contact of second stance after block clearance. This study showed that adult athletes rely on higher knee power generation during the first stance to induce longer step length and therefore higher velocity. In younger athletes, power generation of hip was more dominant.     

Teachers' use and children's preferences of rewards in elementary school

This study examined teacher reports of reward use and students' preferences for rewards across elementary school grades. Forty-eight urban elementary school teachers indicated which of four basic categories of rewards (edible, tangible, activity, and social rewards) they use in their classrooms and their evaluation of the effectiveness of these rewards for their age group of students. Ninety-eight second through fifth graders randomly selected to represent the students assigned to these teachers were individually administered a reward preference survey. Findings revealed high reward use by teachers. Children reported a wide variety of reward preferences, with no significant gender or age differences found. Additionally, there was no clear relationship between teacher use and children's preferences. Implications for intervention programming are discussed.     

精英足球运动员教育、训练与人才培养路径

儿童和青少年时期系统的足球训练,可以促进年轻足球运动员专项技能和专项体能的发展。旨在结合最新的研究成果、科学知识和应用实践,区分5岁到成年足球运动员的训练目标和方法,审视足球长期教育过程是否符合现代足球训练、运动表现和比赛的要求。强调各个年龄组足球运动员应有特定的足球教育理念、训练目标和方法,这对青春期（U15和U17）及青春期后（U19和U21）的足球运动员尤其重要,因为他们必须准备并确保顺利过渡到精英足球运动员水平。     

Changes in the perception of action possibilities while climbing to fatigue on a climbing wall

In two experiments we examined changes in the perception of action possibilities as a function of exertion. In Experiment 1, participants repeatedly climbed on a climbing wall in a series of trials that progressively increased in number to 10 trials, resulting in increased exertion. Before and during climbing, the participants judged their maximum reaching height and perceived exertion. On a separate day, participants climbed another 10 trials while performing actual maximum reaches. Higher perceived exertion was associated with decreases in perceived maximum reach while the actual reaches did not decrease. However, the perceptual changes occurred early during task execution when the participants were not yet fatigued. When exertion set in, neither perceived nor actual maximum reaching appeared to be affected. In Experiment 2, we included exhaustion trials. The findings replicated the early changes in perception observed in Experiment 1, which may be explained by hands-on experience with the task. Furthermore, while climbing to exhaustion, perceptual judgements largely changed in keeping with changes in the actual maximum reach. Thus, there appeared to be a functional relationship between participants' actual action capabilities, rather than their state of physical fatigue per se, and perceived action possibilities.