The Role of Heads of Department in the Professional Development of Educators: A Distributed Leadership Perspective

The qualitative study reported on was, undertaken from a distributed leadership perspective, and was an attempt to provide understanding of how heads of department (HoDs) develop educators within the organisational context of different schools and subject departments. The findings are related to the current policy framework for professional development in South African schools. Two fee-paying and two non-fee-paying schools were selected and interviews were conducted with HoDs from single subject (unitary) and multi-subject (federal or confederate) departments in each school. The data was transcribed, coded, analysed and related to the research question. The findings confirmed that HoDs are a key link between principals and the educators in their classrooms. This supports the view that HoDs have formal responsibilities and accountabilities and they wield a horizontal and a vertical influence. Recommendations are made to improve professional development practice by HoDs in particular and in the education system in general.     

Widely linear estimation for multisensor quaternion systems with mixed uncertainties in the observations

The optimal widely linear state estimation problem for quaternion systems with multiple sensors and mixed uncertainties in the observations is solved in a unified framework. For that, we devise a unified model to describe the mixed uncertainties of sensor delays, packet dropouts and uncertain observations by using three Bernoulli distributed quaternion random processes. The proposed model is valid for linear discrete-time quaternion stochastic systems measured by multiple sensors and it allows us to provide filtering, prediction and smoothing algorithms for estimating the quaternion state through a widely linear processing. Simulation results are employed to show the superior performance of such algorithms in comparison to standard widely linear methods when mixed uncertainties are present in the observations.     

Assessing a Remedial Intervention Programme in Developing the Planning Skills of Grade 4 and 5 Learners

The search for assessment procedures that are more fair and useful have led to the investigation of alternatives to traditional forms of intellectual assessment. This study explored an alternative which combined a dynamic assessment approach with the Planning, Attention, Simultaneous and Successive Processing (PASS) model of cognitive processing. The aim was to investigate the effectiveness of a planning intervention programme based on Feuerstein’s criteria for Mediated Learning Experience (MLE) with a group of Grade 4 and 5 remedial school learners who presented with a range of barriers to learning. Twenty six learners were assigned to the experimental group and 25 to the control group. The results showed that there was a significant improvement in the experimental group’s Planning Scale score on the Cognitive Assessment System, following the intervention. These results imply that children often have far greater potential than is realised and that intentional mediation can help to enhance cognitive functioning and assist in further developing children’s learning potential.     

Using a digital game as an advance organizer

The use of digital games as an instructional tool has garnered increasing attention in the education community. Empirical work supported by theory on the learning affordances of digital games allowed the game-based learning community to arrive at the consensus that digital games provide an excellent medium for the acquisition of skills and the exploration of concepts. The field, however, lacks research on how best to teach with games. For example, an unanswered question is whether gameplay should take place before instruction, after instruction, or integrated throughout in order to maximize the effectiveness of the game. To answer this question, a study was conducted with 103 middle school students who either played a digital game designed to teach algebraic concepts before receiving formal instruction, received formal instruction before playing the game, or received formal instruction intermittently during their gameplay session. The results indicate while on average all participants showed improvement in terms of learning, those who played the game before receiving instruction showed significant improvement. These results provide evidence supporting the theory that games are effective when used as an advanced organization tool.     

Activity of periscapular muscles and its correlation with external oblique during push-up: Does scapular dyskinesis change the electromyographic response?

Scapular dyskinesis is the term used to describe changes in the positioning or movement of the scapula. Such dysfunction is associated with changes in the activation of the scapular muscles. However, the influence of the axial muscles on the scapular muscles activity of subjects with scapular dyskinesis is unknown. This study aimed to compare the electromyography (EMG) activity of periscapular muscles and its correlation with the external oblique muscle during the execution of push-up performed in different surfaces, in volunteers with and without scapular dyskinesis. Thirty-six men, divided in two groups (control and dyskinesis), performed push-up on stable and unstable surface. The EMG activity of serratus anterior (SA_5th and SA_7th fibers), upper (UT) and lower (LT) trapezius, external oblique (EO) was recorded during execution of each task condition. Statistical analyzes were performed using two way ANOVA repeated measures and Pearson correlation. It was observed effect of interaction between factors, being evidenced increased activity of UT, SA_7th and OE for the control group and decreased activity of SA_5th, SA_7th and EO for dyskinesis group during execution of push-up on unstable surface. In both groups positive correlations (r > 0.47) were observed between EMG activity of SA and EO. In the exercises tested, there seems to be an anatomical and functional relationship between the SA and EO muscles. The use of the unstable surface promotes increased neuromuscular demand, but the neuromuscular strategies appear to differ between groups.     

Perceived neighborhood environmental characteristics and different types of physical activity among Brazilian adolescents

Little is known about the association between environmental characteristics and types of physical activity in adolescents in a Latin American context. The aim of this study was to examine the association between perceived neighborhood environmental characteristics and different types of physical activity in 2,874 adolescents from Joao Pessoa, Paraiba State, Northeastern Brazil. The types of activity measured by questionnaire (≥10 min/day) included sports, physical exercises, active commuting and recreational activities. Neighborhood characteristics were measured by a 15-item scale. Multilevel analyses showed that adolescents who reported “having places they liked to go to” (OR = 1.41; 95%CI: 1.10–1.79) and “places with opportunities to practice” (OR = 1.29; 95%CI: 1.01–1.65) were more likely to play sports. “Seeing interesting things while walking” (OR = 1.24; 95%CI: 1.01–1.53) and “Seeing other adolescents engaged in physical activity” (OR = 1.47; 95%CI: 1,05–2,06) were associated with exercises. “Seeing other adolescents engaged in physical activity” (OR = 1.47; 95%CI: 1.18–1.82), “the neighborhood is not violent” (OR = 1.29; 95%CI: 1.04–1.60) and “having places they like to go to” (OR = 1.59; 95%CI: 1.13–2.25) were positively associated and “places with opportunities to practice” (OR = 0.79; 95%CI: 0.63–0.98) inversely related to active commuting. “Seeing other adolescents engaged in physical activities” (OR = 1.31; 95%CI: 1.05–1.63) and “seeing interesting things while walking” (OR = 1.26; 95%CI: 1.02–1.56) were associated with recreational activities. Neighborhood environmental characteristics associated with the physical activity vary with the type of practices adopted by adolescents.     

Baseline Intraocular Pressure Is Associated With Subjective Sensitivity to Physical Exertion in Young Males

Purpose: The purposes of this study were to (a) investigate the effect of physical effort (cycling for 60 min at 60 ± 5% of individually computed reserve heart-rate capacity), combined with 2 different levels of cognitive demand (2-back, oddball), on intraocular pressure (IOP) and subjective judgments of perceived exertion (ratings of perceived exertion [RPE]), affect (Affective Valence subscale of the Self-Assessment Manikin [SAM]), and mental workload (National Aeronautics and Space Administration Task Load Index [NASA-TLX]); and (b) ascertain whether baseline IOP, measured before exercise, is associated with individual differences in subjective assessments of effort and affective response during exercise. Method: Seventeen participants (M_age = 23.28 ± 2.37 years) performed 2 physical/cognitive dual tasks, matched in physical demand but with different mental requirements (2-back, oddball). We assessed IOP before exercise, after 2 min of active recovery, and after 15 min of passive recovery, and we also collected RPE and SAM measures during the sessions (28 measurement points). We used NASA-TLX and cognitive performance as checks of the mental manipulation. Results: (a) Intraocular pressure increased after concomitant physical/mental effort, with the effect reaching statistical significance after the 2-back task (p = .002, d = 0.35) but not after the oddball condition (p = .092, d = 0.29). (b) Baseline IOP was associated with subjective sensitivity to effort and showed statistical significance for the oddball condition (p = .03, ?_p² = .622) but not for the 2-back task (F < 1). Conclusions: Results suggest a relationship between IOP and physical/cognitive effort, which could have implications for the management of glaucoma. Additionally, a rapid measure of IOP could be used as a marker of individual effort sensitivity in applied settings.     

The influence of body discourses on adolescents’ (non)participation in physical activity

Drawing on semi-structured interviews with older adolescents, this article examines how healthism, ideal body discourses and performative body discourses influence their (non)participation in physical activity (PA) and their identity construction concerning exercise, sport and physical education. We illustrate that body transformation through PA, and related slim body desire and the fear of masculinised female bodies, affect adolescents’ decisions to engage in or drop out of sport. Also, a non-hegemonic body shape combined with a display of low physical competence triggers classmate and teachers’ rejection and marginalisation, affecting adolescents’ construction of embodied identities and preventing them from being active. Finally, adolescents who are competent in sport are less influenced by ideal body discourses than by performative body discourses. We highlight the health promotion effects of these hegemonic discourses and suggest strategies to challenge them.     

Accuracy,intra- and inter-unit reliability,and comparison between GPS and UWB-based position-tracking systems used for time–motion analyses in soccer

There is interest in the accuracy and inter-unit reliability of position-tracking systems to monitor players. Research into this technology, although relatively recent, has grown exponentially in the last years, and it is difficult to find professional team sport that does not use Global Positioning System (GPS) technology at least. The aim of this study is to know the accuracy of both GPS-based and Ultra Wide Band (UWB)-based systems on a soccer field and their inter- and intra-unit reliability. A secondary aim is to compare them for practical applications in sport science. Following institutional ethical approval and familiarization, 10 healthy and well-trained former soccer players (20?±?1.6 years, 1.76?±?0.08?cm, and 69.5?±?9.8?kg) performed three course tests: (i) linear course, (ii) circular course, and (iii) a zig–zag course, all using UWB and GPS technologies. The average speed and distance covered were compared with timing gates and the real distance as references. The UWB technology showed better accuracy (bias: 0.57–5.85%), test–retest reliability (%TEM: 1.19), and inter-unit reliability (bias: 0.18) in determining distance covered than the GPS technology (bias: 0.69–6.05%; %TEM: 1.47; bias: 0.25) overall. Also, UWB showed better results (bias: 0.09; ICC: 0.979; bias: 0.01) for mean velocity measurement than GPS (bias: 0.18; ICC: 0.951; bias: 0.03).