The influence of ventilatory control on heart rate variability in children

The aim of this study was to determine the influence of breathing frequency and tidal volume on resting heart rate variability in children aged 9 years ( n = 29) and 16 years ( n = 19). Heart rate variability was measured in four conditions: (1) without the control of ventilation followed at random by (2) a fixed breathing frequency of 12 breaths· min -1 , (3) a breathing frequency of 12 breaths· min -1 but with a fixed tidal volume of 30% vital capacity and (4) a fixed breathing frequency of 6 breaths·min -1 and a tidal volume of 30% vital capacity. A total of 128 RR intervals (the time between two spikes in the heart rate) were detected and absolute high- and low-frequency spectral components were calculated using autoregressive modelling. The younger children were unable to control ventilation to achieve conditions 3 and 4; therefore, a 2 2 2 (group 2 condition) analysis of variance was used to analyse conditions 1 and 2. There were significant interactions between group and heart rate variability conditions for the low-frequency component and the ratio of low to high frequencies ( P ? 0.001). The main effect for condition showed that at 12 breaths· min -1 with no fixed tidal volume there was a significantly higher standard deviation of the RR interval, total power and high-frequency ( P ? 0.01) and lowfrequency spectral components ( P ? 0.05) than in the condition with no ventilatory control. Across the four breathing conditions for the older participants, the high-frequency spectral component was significantly higher in the condition at 6 breaths· min -1 with a fixed tidal volume than in that with no ventilatory control ( P ? 0.005); the ratio of high to low frequencies was significantly lower for the spontaneous condition than those performed at 12 breaths· min -1 ( P ? 0.001). The results provide evidence of the need for ventilatory control when assessing short-term resting heart rate variability in children.     

Sequence-dependent rotation axis changes in tennis

The purpose of this study was to evaluate the role of rotation axes during a tennis serve. A motion capture system was used to evaluate the contribution of the potential axes of rotation (minimum inertia axis, shoulder-centre of mass axis and the shoulder-elbow axis) during the four discrete tennis serve phases (loading, cocking, acceleration and follow through). Ten ranked athletes (International Tennis Number 1–3) repeatedly performed a flat service aiming at a target on the other side of the net. The four serve phases are distinct and thus, each movement phase seems to be organised around specific rotation axes. The results showed that the limbs’ rotational axis does not necessarily coincide with the minimum inertia axis across the cocking phase of the tennis serve. Even though individual serving strategies were exposed, all participants showed an effect due to the cocking phase and changed the rotation axis during the task. Taken together, the results showed that despite inter-individual differences, nine out of 10 participants changed the rotation axis towards the minimum inertia and/or the mass axis in an endeavour to maximise external rotation of the shoulder to optimally prepare for the acceleration phase.     

Cognitive design for instructional design

There is strong interest in the field of instructional design in building expert systems that can provide advice to inexperienced instructional designers. This paper questions whether the expert systems model to advice-giving is in fact appropriate for a design process such as instructional design. An alternate approach based on case-based reasoning and the critic approach to advice-giving is considered to be better adapted to the cognitive needs of this task. The cognitive constraints of the task are used to orient the design of an instructional design workbench. The concept of an ID workbench illustrates the direct application of cognitive science to a complex practical task in the area of design.     

Neutrality and impartiality in public education: the French investment in philosophy,teaching about religions,and moral and civic education

In France, there is no religious education in state schools. ‘Convictional education’ appeared by drawing its perimeter around three educational subjects: philosophy, teaching about religions, and moral and civic education. Today, the French school is facing new challenges in a highly secularised society on which religion is laying new claims. As an institution, it is not neutral insofar as it proceeds from a political philosophy that evolved from the French Revolution. It is within the operative framework of this philosophy and with specific teaching practices that it intends to combine unity and plurality within itself.     

Analysis of the trajectories of Science graduates: applying Bourdieu and Sen

Abstract

We bring together the theories of Bourdieu and Sen in order to understand the processes that influence the study paths chosen by young people with a general degree from a science university in France. The weighting of economic and cultural capital within study options taken in secondary education and during the premier cycle (the first three years of tertiary education) helps characterise elements of students’ trajectories which either stymie or reinforce a nonetheless dominant reproduction.     

Who's in the mirror? Self-other discrimination in specular images by four- and nine-month-old infants

This research investigated the early determinants of self-other discrimination in infancy. Ninety-six 4- and 9-month-old infants were placed facing a live image either of themselves or of another person (experimenter) mimicking them. The specular image was either contingent (on-line), or contingent with a 2-s delay. After a first 1-min presentation, the video image of either the self or the other was suddenly frozen for 1 min (still-face episode). This was followed by a last minute of live presentation. From 4 months of age, infants appeared to perceive and act differentially when facing the specular image of themselves or the mimicking other. In general, infants tended to smile more, look more, and have more protracted first-look duration toward the mimicking other compared with the self. Developmentally, 9-month-olds showed markedly more social initiatives toward the mimicking other compared with the self during the still-face episode. In all, these results indicate that infants develop self-other discrimination in specular images long before mirror self-recognition, which is typically reported by the second year. Discrimination of the self from other is interpreted as a precursory ability and a perceptual foundation of later conceptual self development.     

New Insights on Picasso’s Blue Period Painting La famille Soler

The study of La Famille Soler using non-invasive imaging, molecular, structural, and elemental analysis allowed the re-examination of changes of the work. Considered as the earliest of Picasso’s versions of Le déjeuner sur l’herbe by E. Manet, evidence suggests that an underlying landscape painted by Vidal in 1903 also referred to Manet’s masterpiece. On the other hand, new results suggest that the cubist sketch undertaken by Picasso in 1912, prior to the current blue background, could be an uncompleted transformation of Vidal’s landscape into synthetic cubism. Through study the main pigments used in the underlying compositions were successfully identified.