High bar swing performance in novice adults: effects of practice and talent

An individual's a priori talent can affect movement performance during learning. Also, task requirements and motor-perceptual factors are critical to the learning process. This study describes changes in high bar swing performance after a 2-month practice period. Twenty-five novice participants were divided by a priori talent level (spontaneous-talented [ST] and nonspontaneous-talented [NST]) and compared to experienced gymnasts. Additionally, we assessed their perception of their performance level before and after practice. We defined three events independently for hip (H) and shoulder (S) angle joints and for the lag between consecutive events (phases [P]): the smallest angle during downswing (P1H, P1S), the largest angle after P1 (P2H, P2S), and the smaller angle during upswing (P3H, P3S). Movement performance variables were the maximum elevation on the downswing (Pi) and the upswing (Pf), and the total path between both (swing amplitude). Data were collected during pre- and postpractice sessions by two video cameras. At the end of both sessions, participants drew a sketch to represent their perception of their performance level relative to the Pi, Pf and the hip events. Results showed a similar practice effect in the swing amplitude in both novice groups. However the ST group 's performance and perception variables on the downswing improved more than the NST group due to practice. This study suggests that (a) downswing improvements were easier than in the upswing, possibly due to familiarity of the visual reference in combination with proprioceptive feedback; and (b) being ST may involve a better orfaster gain in perception of self-action compared to NST.     

Evaluating the school assets that promote positive adolescent development from the perspective of the student / La evaluación de los activos escolares para el desarrollo positivo adolescente desde la perspectiva del alumnado

Abstract

The aim of this study was to develop a valid and reliable instrument for evaluating students’ perceptions of their school’s key strengths, or school assets, using the positive adolescent development approach. To do this, we first created a scale after carrying out a review of the instruments already in use to evaluate school climate and aspects related to the school context which have been identified as factors that promote the socio-personal development and adjustment of adolescents. Secondly, expert judgement was sought to ensure the validity of the scale’s content. And finally, in order to analyse the psychometric properties of the scale, it was given to a sample of 2,400 adolescents (1,068 boys and 1,332 girls) aged 12–17 (M = 14.73, SD = 1.25) in secondary education in state and private schools in Western Andalusia. The results obtained endorsed the scale’s psychometric properties. The external and predictive validity of the instrument remains to be tested in future studies.     

A synthesis of research on effectiveness of school-based drug prevention programmes / Claves de eficacia de los programas de prevención de consumo de sustancias en el contexto escolar: una meta-revisión

Abstract

Relevant information on effectiveness of school-based drug prevention programmes is available. Despite this, there is still contradictory evidence that makes it necessary to continue to shed light on this issue. Based on a synthesis research method, the aim of this study was to determine the relevant variables that enhance the efficacy of these programmes and to determine the weight of their empirical evidence. Furthermore, several features of the evaluation designs whose variables had been proven effective were examined. A systematic review of periodical literature was conducted, which led us to extract 1,622 papers, of which 17 studies were analysed. An in-depth analysis of these publications led us to identify 29 key variables associated with the efficacy of the programme, which were ranked according to the weight of their empirical evidence. Moreover, the characteristics of the studies included in the review highlighted the need to improve the rigorousness and quality of the evaluation designs in this field.     

The end of innocence: historiography and representation in the discursive practice of LD

In this article, I discuss two interrelated sets of challenges that the discursive practice of learning disability (LD) will need to address, namely, issues associated with the development of a historiography of special education and a more complex understanding of representation issues. I use social theory to address these challenges and raise questions the LD field will need to grapple with as we move toward the consolidation of discursive practices.     

Defending Constructivism in Science Education

After an impressive development throughout the last two decades, supported by a greatamount of research and innovation, science education seemed to be becoming a newscientific domain. This transformation of Science Education into a specific field of researchand knowledge is usually associated with the establishment of what has been called anemergent consensus about constructivist positions. However, some voices have begunto question these constructivist positions and therefore the idea of an advancementtowards a coherent body of knowledge in the field of science education. The goalof this work is to analyse some of the current criticisms of the so-called constructivistorientations and to study their implications for the development of science education asa coherent body of knowledge.     

The many faces of mobility: Using bibliometric data to measure the movement of scientists

This paper presents a methodological framework for developing scientific mobility indicators based on bibliometric data. We identify nearly 16 million individual authors from publications covered in the Web of Science for the 2008–2015 period. Based on the information provided across individuals’ publication records, we propose a general classification for analyzing scientific mobility using institutional affiliation changes. We distinguish between migrants--authors who have ruptures with their country of origin--and travelers--authors who gain additional affiliations while maintaining affiliation with their country of origin. We find that 3.7% of researchers who have published at least one paper over the period are mobile. Travelers represent 72.7% of all mobile scholars, but migrants have higher scientific impact. We apply this classification at the country level, expanding the classification to incorporate the directionality of scientists’ mobility (i.e., incoming and outgoing). We provide a brief analysis to highlight the utility of the proposed taxonomy to study scholarly mobility and discuss the implications for science policy.     

Protection against muscle damage in competitive sports players: the effect of the immunomodulator AM3

Strenuous physical exercise of the limb muscles commonly results in damage, especially when that exercise is intense, prolonged and includes eccentric contractions. Many factors contribute to exercise-induced muscle injury and the mechanism is likely to differ with the type of exercise. Competitive sports players are highly susceptible to this type of injury. AM3 is an orally administered immunomodulator that reduces the synthesis of proinflammatory cytokines and normalizes defective cellular immune fractions. The ability of AM3 to prevent chronic muscle injury following strenuous exercise characterized by eccentric muscle contraction was evaluated in a double-blind and randomized pilot study. Fourteen professional male volleyball players from the First Division of the Spanish Volleyball League volunteered to take part. The participants were randomized to receive either placebo (n?=?7) or AM3 (n?=?7). The physical characteristics (mean±s) of the placebo group were as follows: age 25.7±2.1 years, body mass 87.2±4.1?kg, height 1.89±0.07?m, maximal oxygen uptake 65.3±4.2?ml?·?kg^?1?·?min^?1. Those of the AM3 group were as follows: age 26.1±1.9 years, body mass 85.8±6.1?kg, height 1.91±0.07?m, maximal oxygen uptake 64.6±4.5?ml?·?kg^?1?·?min^?1. All participants were evaluated for biochemical indices of muscle damage, including concentrations of aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, creatine kinase (CK) and its MB fraction (CK-MB), myoglobin, lactate dehydrogenase, urea, creatinine and γ-glutamyltranspeptidase, both before and 30 days after treatment (over the peak of the competitive season). In the placebo group, competitive exercise (i.e. volleyball) was accompanied by significant increases in creatine kinase (494±51 to 560±53?IU?·?l^?1, P?<?0.05) and myoglobin (76.8±2.9 to 83.9±3.1?μg?·?l^?1, P?<?0.05); aspartate aminotransferase (30.8±3.0 to 31.1±2.9?IU?·?l^?1) and lactate dehydrogenase (380±31 to 376±29?IU?·?l^?1) were relatively unchanged after the 30 days maximum effort. AM3 not only inhibited these changes, it led to a decrease from baseline serum concentrations of creatine kinase (503±49 to 316±37?IU?·?l^?1, P?<?0.05) and myoglobin (80.1±3.2 to 44.1±2.6?IU?·?l^?1, P?<?0.05), as well as aspartate aminotransferase (31.1±3.3 to 26.1±2.7?IU?·?l^?1, P?<?0.05) and lactate dehydrogenase (368±34 to 310±3?IU?·?l^?1, P?<?0.05). The concentration of CK-MB was also significantly decreased from baseline with AM3 treatment (11.6±1.2 to 5.0±0.7?IU?·?l^?1, P?<?0.05), but not with placebo (11.4±1.1 to 10.8±1.4?IU?·?l^?1). In conclusion, the use of immunomodulators, such as AM3, by elite sportspersons during competition significantly reduces serum concentrations of proteins associated with muscle damage.     

Spatial and seasonal characterization of net primary productivity and climate variables in southeastern China using MODIS data

We developed a sophisticated method to depict the spatial and seasonal characterization of net primary productivity (NPP) and climate variables. The role of climate variability in the seasonal variation of NPP exerts delayed and continuous effects. This study expands on this by mapping the seasonal characterization of NPP and climate variables from space using geographic information system (GIS) technology at the pixel level. Our approach was developed in southeastern China using moderate-resolution imaging...