Knee joint position sense of roller hockey players: a comparative study

This study aimed to compare knee joint position sense of roller hockey players with an age-matched group of non-athletes. Forty-three male participants voluntarily participated in this cross-sectional study: 21 roller hockey players (mean age: 23.2 ± 4.2 years old, mean weight: 81.8 ± 9.8 kg, mean height: 180.5 ± 4.1 cm) and 22 age-matched non-athletes (mean age: 23.7 ± 3.9 years old, mean weight: 85.0 ± 6.2 kg, mean height: 181.5 ± 5.0 cm). Knee joint position sense of the dominant limb was evaluated using a technique of open-kinetic chain and active knee positioning. Joint position sense was reported using absolute, relative and variable angular errors. The main results indicated that the group of roller hockey players showed significantly lower absolute (2.4 ± 1.2º vs. 6.5 ± 3.2º, p ≤ 0.001) and relative (1.7 ± 2.1º vs. 5.8 ± 4.4º, p ≤ 0.001) angular errors in comparison with the non-athletes group. In conclusion, the results from this present study suggest that proprioceptive acuity, assessed by measuring joint position sense, is increased in roller hockey players. The enhanced proprioception of the roller hockey players could contribute to injury prevention and improved performance during sporting activities.     

The effect of different foot and hand set-up positions on backstroke start performance

Foot and hand set-up position effects were analysed on backstroke start performance. Ten swimmers randomly completed 27 starts grouped in trials (n = 3) of each variation, changing foot (totally immersed, partially and totally emerged) and hand (lowest, highest horizontal and vertical) positioning. Fifteen cameras recorded kinematics, and four force plates collected hands and feet kinetics. Standardised mean difference and 95% confidence intervals were used. Variations with feet immersed have shown lower vertical centre of mass (CM) set-up position (0.16 m), vertical impulse exerted at the hands, horizontal and vertical impulse exerted at the feet (0.28, 0.41, 0.16 N/BW.s, respectively) than feet emerged with hands horizontal and vertically positioned. Most variations with feet partially emerged exhibited higher and lesser vertical impulse exerted at hands than feet immersed and emerged (e.g. vertical handgrip, 0.13, 0.15 N/BW.s, respectively). Variation with feet emerged and hands on the lowest horizontal handgrip depicted shorter horizontal (0.23, 0.26 m) and vertical CM positioning at flight (0.16, 0.15 m) than the highest horizontal and vertical handgrip, respectively. Start variations have not affected 15-m time. Variations with feet partially or totally emerged depicted advantages, but focusing on the entry and underwater biomechanics is relevant for a shorter start time.     

Interdisciplinary therapy changes superoxide dismutase activity and adiponectin in obese adolescents: a randomised controlled trial

The objective of this study is to evaluate the effect of interdisciplinary therapy in the parameters of the oxidative stress and the anti-inflammatory responses of obese adolescents. We selected 57 participants, who were randomly divided into 2 groups: interdisciplinary therapy group and a control group. After 6 months of intervention, 17 participants of the interdisciplinary therapy group and 8 of the control group returned for re-evaluation. The interdisciplinary therapy group participated in a treatment with 4 weekly sessions of exercise, a weekly group therapy session and a weekly nutritional education session. Blood parameters of oxidative stress and anti-inflammatory response were evaluated. The results demonstrated that there were significant increases in the interdisciplinary therapy group for superoxide dismutase activity (6.56 ± 3.22 to 11.40 ± 7.49) and ferric-reducing antioxidant potential concentration (532.91 ± 106.48 to 573.25 ± 112.57), although adiponectin levels did not reduce (40.9 ± 29.34 to 49.05 ± 41.22). A significant decrease in nitrite levels was also found (14.23 ± 8.48 to 11.45 ± 6.05). In the control group, significant reduction was found in adiponectin (31.56 ± 18.88 to 18.01 ± 11.66). This study suggests that interdisciplinary therapy for 6 months was effective in improving the anti-inflammatory responses and the antioxidant defences in obese adolescents.     

Are the new starting block facilities beneficial for backstroke start performance?

We aimed to analyse the handgrip positioning and the wedge effects on the backstroke start performance and technique. Ten swimmers completed randomly eight 15 m backstroke starts (four with hands on highest horizontal and four on vertical handgrip) performed with and without wedge. One surface and one underwater camera recorded kinematic data. Standardised mean difference (SMD) and 95% confidence intervals (CI) were used. Handgrip positioning did not affect kinematics with and without wedge use. Handgrips horizontally positioned and feet over wedge displayed greater knee angular velocity than without it (SMD = ?0.82; 95% CI: ?1.56, ?0.08). Hands vertically positioned and feet over wedge presented greater take-off angle (SMD = ?0.81; 95% CI: ?1.55, ?0.07), centre of mass (CM) vertical positioning at first water contact (SMD = ?0.97; 95% CI: ?1.87, ?0.07) and CM vertical velocity at CM immersion (SMD = 1.03; 95% CI: 0.08, 1.98) when comparing without wedge use. Swimmers extended the hip previous to the knee and ankle joints, except for the variant with hands vertically positioned without wedge (SMD = 0.75; 95% CI: ?0.03, 1.53). Swimmers should preserve biomechanical advantages achieved during flight with variant with hands vertically positioned and wedge throughout entry and underwater phase.     

Unveiling the Colours of Cellulose Nitrate Black and White Film-based Negatives in Colonial Photography

ABSTRACT

Aiming at contributing to the preservation of black and white (B&W) film-based negatives held by Portuguese archives, four photographic collections from the first half of the twentieth century were selected for study. During the macro assessment of the collections the preservation condition and hues found in photographic negatives from the Elmano Cunha e Costa (ECC) were noticed, distinguishing this collection from the remaining ones. Additional attention was given considering that the ECC collection was formed in a colonial context in the 1930s, while the others were formed on the Portugal mainland. The ECC collection results from an ethnographic survey of Angolan tribes recorded with B&W film-based negatives. In this collection, sets of negatives with pink, lemon yellow, greenish, orange brownish, and red brownish hues were found. To identify the origin of such hues, the image layer was analysed by microscale energy-dispersive X-ray fluorescence (μ EDXRF) and scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX). Additionally, to assess the base decay and its effect on the formation of hues, the plastic supports were characterized by Fourier transform infrared microscopy (μ FTIR). To complement the assessment of the film-base decay, pH was measured by using combined microelectrodes. The identification of mercury, iodine, chromium, and iron by μ EDXRF allowed correlation of the hues found in the negatives with chemical corrective treatments performed to improve the image quality. SEM-EDX confirmed those results and proved that the elements found were in the photographic emulsion layer. The results obtained are relevant since the hues identified may now be used as markers to indicate the technical work performed on colonial photography. Additionally, the visual and molecular assessment of the negatives’ supports (good to fair condition) allow proposing that the original storage conditions may have had a beneficial contribution to their present condition.     

Socio‐scientific controversies and students' conceptions about scientists

This article discusses the results of a mainly qualitative study into possible impacts of recent controversial socio‐scientific issues on a group of Portuguese secondary school students regarding their conceptions about scientists. The 86 participants: (1) answered a questionnaire with open‐ended questions; and (2) wrote a science fiction story involving a group of scientists working on a particular situation of her/his choice. Next, semi‐structured interviews were carried out to clarify and discuss the ideas embodied in the stories and mentioned in the questionnaire. All data underwent a process of content analysis. The socio‐scientific controversies recently discussed, and the way science and scientists are depicted in the media, seem to have produced some impact on students' conceptions about scientists. Based on the results obtained, some remarks and educational implications are discussed.     

Does moderate-intensity continuous training result in greater total energy expenditure compared to high-intensity interval training?

Recently in the Journal of Sports Sciences, Schaun et al. published a study on the comparison of energy expenditure between high-intensity interval training and moderate continuous training performed in water. With this Letter to the Editor, we would like to comment on the methodological aspects that should be considered to analyze the results presented, as well as the conclusions.

Abbreviations: CONT, moderate-intensity continuous training; EPOC, excess post-exercise oxygen consumption; HIIT, high-intensity interval training; VO2max, maximal oxygen consumption.     

Invest for the Long Term or Attend to Immediate Needs? Schools and the Employment of Less Educated Youths and Adults

For the past 20 years, researchers worldwide have shared a consensus that tracking leads to failure in school. But educational systems continue to use this practice for many reasons. One argument used to support the practice is that students who enter the vocational track early in their careers tend to enter the labour market more quickly. Data show, however, that when these people are in their 40s, they become the most vulnerable to poverty, especially during periods of economic recession. In addition to moving towards more comprehensive educational systems as the best long-term way to improve the chances of all future adults, our research demonstrates that schools can play a key role in preventing and reversing the risk of unemployment and poverty of low educated youth. The INCLUD-ED project has analysed effective actions in eight European countries (Slovenia, United Kingdom, Italy, Austria, Romania, Belgium, Finland, and Spain) that respond to the educational needs of those who have experienced tracking. These effective alternatives are vocational programmes that include an academic-type of curriculum and allow students to move to higher education, as well as adult education programmes in schools which meet families' training needs, improving their opportunities in the labour market.     

PUKHA: a new pedagogical experience

Society needs responsible leaders and entrepreneurs. CDIO (conceive, design, implement and operate) is a framework for engineering education based on outcomes, more than on contents, that has been adopted by a growing number of engineering educational institutions for producing the next generation of engineering leaders. In order to support engineering students to become entrepreneurs and to bear other concerns than merely technical on today's rapid changing world, the authors believe the CDIO syllabus needs to be improved, and therefore propose a pre requisite to a useful CDIO perspective: IdEF, standing for Identify, Evaluate and Formulate real problems and needs. Based on this concept, this paper describes a new pedagogical project framework (PUKHA - to project, to undertake, to know how to achieve). Within PUKHA projects, more than 300 students have trained and checked their will, risk, responsibility, communication, leadership and entrepreneurship over the last three years.     

Congenital learning,organisational performance and work-life balance culture

A possible explanation for the numerous failures in the implementation and use of work-life balance (WLB) practices may relate to the fact that the majority of companies have introduced them without exploring the nature and extent of their founders’ or owners’ prior knowledge of WLB and WLB practices. This paper analyses the relationships between congenital learning and WLB culture and tries to identify whether WLB culture impacts on business performance through an empirical study of 229 small and medium-sized enterprises (SMEs) in the Spanish metal industry. Our findings show that in order to create positive attitudes toward WLB, managers need to create and support a learning process. These findings provide interesting insights into the drivers of organisational performance for SMEs that develop and support a WLB-supporting culture.