Sodium bicarbonate ingestion does not alter the slow component of oxygen uptake kinetics in professional cyclists

We examined the effects of pre-exercise sodium bicarbonate (NaHCO3) ingestion on the slow component of oxygen uptake (VO2) kinetics in seven professional road cyclists during intense exercise. One hour after ingesting either a placebo or NaHCO3 (0.3 g x kg body mass(-1)), each cyclist (age, 25 +/- 2 years; VO2max, 74.7 +/- 5.9 ml x kg(-1) x min(-1); mean +/- s) performed two bouts of 6 min duration at an intensity of 90% VO2max interspersed by 8 min of active recovery. Gas exchange and blood data (pH, blood lactate concentration and [HCO3-]) were collected during the tests. In both bouts, the slow component of VO2 was defined as the difference between end-exercise VO2 and the VO2 at the end of the third minute. No significant difference was found in the slow component of VO2 between conditions in the first (NaHCO3, 210 +/- 69 ml; placebo, 239 +/- 105 ml) or second trial (NaHCO3, 123 +/- 88 ml; placebo, 197 +/- 101 ml). In conclusion, pre-exercise NaHCO3 ingestion did not significantly attenuate the VO2 slow component of professional road cyclists during high-intensity exercise.     

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.     

Transactional Links Between Teacher–Child Relationship Quality and Perceived Versus Sociometric Popularity: A Three‐Wave Longitudinal Study

This study examined how peer relationships (i.e., sociometric and perceived popularity) and teacher–child relationships (i.e., support and conflict) impact one another throughout late childhood. The sample included 586 children (46% boys), followed annually from Grades 4 to 6 (M_age.wave1 = 9.26 years). Autoregressive cross‐lagged modeling was applied. Results stress the importance of peer relationships in shaping teacher–child relationships and vice versa. Higher sociometric popularity predicted more teacher–child support, which in turn predicted higher sociometric popularity, beyond changes in children's prosocial behavior. Higher perceived popularity predicted more teacher–child conflict (driven by children's aggressive behavior), which, in turn and in itself, predicted higher perceived popularity. The influence of the “invisible hand” of both teachers and peers in classrooms has been made visible.     

Worldwide variation in the performance of children and adolescents: An analysis of 109 studies of the 20-m shuttle run test in 37 countries

Abstract

This study is a meta-analysis of 109 reports of the performance of children and adolescents on the 20-m shuttle run test (20-mSRT). The studies were performed in 37 countries and included data on 418,026 children, tested between 1981 and 2003. Results were expressed as running speed (km · h^?1) at the final completed stage of the 20-mSRT. Raw data were combined with pseudodata using Monte Carlo simulation. The 20-mSRT performances were expressed as z-scores relative to all children of the same age and sex from all countries. An overall “performance index” was derived for each country as the average of the age- and sex-specific z-scores for all children from that country. Factorial analysis of variance was used to compare scores among countries and regions, and between boys and girls of the same age. There was wide and significant (P < 0.0001) global variability in the performance of children. The best performing children were from the Northern European countries Estonia, Iceland, Lithuania, and Finland (0.6 – 0.9 standard deviations above the global average). The worst performing children were from Singapore, Brazil, USA, Italy, Portugal, and Greece (0.4 – 0.9 standard deviations below the global average). There is evidence that performance was negatively related to being overweight, as well as to a country's average temperature.     

Exploring the short-term and maintained effects of strategic instruction on the writing of 4th grade students: should strategies be focused on the process?

Reading and Writing - The principal aim of strategy-focused instruction is to teach students strategies to control their writing processes and achieve quality writing. For this purpose, nine 4th...     

Self-regulated learning and the role of ePortfolios in business studies

Students’ work in ePortfolios was assessed through a case study supported by observation techniques and eQuestionnaires to gather data from a sample of eighty students over a period of 4 years (20 students per academic year). The main purpose of the study was to explore whether ePortfolios can be used efficiently to support the learning process of postgraduate business students taking a course where finance modules were a major component. The use, role and learning value of integrating ePortfolios into the learning process in a higher education institution was analysed over the period of study. The empirical findings suggest that ePortfolios could be used to facilitate and enhance students’ self-regulated learning. Additionally, the role of the instructor was found to be fundamental during early stages of the learning process to guide and coach students on how to use the tool. This role diminished as students became familiar with the course requirements. Overall, students judged the ePortfolio as being positive to their education, noting a significant improvement in their learning experience when compared to a traditional learning approach. The evidence suggests that ePortfolios could be used to support technical and complex modules in a controlled environment. At the same time, ePortfolios were found to be flexible enough to give students creative space by helping them to integrate their own ideas and views through their learning process. Students were also able to offer their instructors feedback on their learning achievements.     

Role Distance in Question: When it is No Longer Participating But Winning Which is Important

The purpose of this study, which follows on from previous work, is to show in what ways sport has surreptitiously changed and become more complex, to the extent that its functioning only imperfectly responds to one of the basics of sport as envisaged by Elias: role distance. That is the propensity of the participants to avoid being caught in the game, which is only a game, defining in this way the social distance which classes sports performers and the relationship of their practice to the contingencies and material necessities of life. The choice of this focal point is another attempt to understand what happens when sport, by transforming itself, becomes more than sport or even another type of sport. In other words, here we wish to discover what makes Elias' model incomplete. Although sport is supposed to contribute to the pacification of social relations, there are still a large number of elements, which in sporting practice, and in its most recent developments, cannot be explained by the theory of the ‘civilising process’.     

The possibilities of exploring nontraditional datasets with young children

Today's world is characterized by the extensive production of data in different scenarios that everyday citizens need to understand for their informed participation in society. With the increase in the availability of data in a society defined by the industrious production of data, the educational system needs to think of possibilities to bring young children closer to the world of data science. This paper presents a nontraditional data exploration experience with an 8-year-old participant helped by a data visualization tool. A task-based interview was conducted while the participant explored a carbon dioxide emission dataset. This paper studied how the participant interrogates the data, draws inferences and exhibits dispositions. At the end, some reflections are presented when introducing the exploration of nontraditional data in teaching.     

A Textbook Analysis to Uncover the Hidden Contributors of Science and Mathematics

Science & Education - Science and mathematics are universal endeavors. However, the historical perspective of science and mathematics has been westernized across the curriculum in the USA....