Sweat lactate response during cycling at 30°C and 18°C WBGT

Sweat lactate reflects eccrine gland metabolism. However, the metabolic tendencies of eccrine glands in a hot versus thermoneutral environment are not well understood. Sixteen male volunteers completed a maximal cycling trial and two 60-min cycling trials [30°C?=?30±1°C and 18°C?=?18±1°C wet bulb globe temperature (WBGT)]. The participants were requested to maintain a cadence of 60 rev?·?min^?1 with the intensity individualized at ～ 90% of the ventilatory threshold. Sweat samples at 10, 20, 30, 40, 50 and 60?min were analysed for lactate concentration. Sweat rate at 30°C (1380±325?ml?·?h^?1) was significantly greater (P<0.05) than at 18°C (632±311?ml?·?h^?1). Sweat lactate concentration was significantly greater (P<0.05) at each time point during the 18°C trial, with values between trials tending to converge across time. During the 30°C trial, both heart rate (20, 30, 40, 50 and 60?min) and rectal temperature (30, 40, 50 and 60?min) were significantly higher than in the 18°C trial. Higher sweat lactate concentrations coupled with lower sweat rates may indicate a greater relative contribution of oxygen-independent metabolism within eccrine glands during exercise at 18°C. Decreases in sweat lactate concentration across time suggest either greater dilution due to greater sweat volume or increased reliance on aerobic metabolism within eccrine glands. The convergence of lactate concentrations between trials may indicate that time-dependent modifications in sweat gland metabolism occur at different rates contingent partially on environmental conditions.     

Relationship between accuracy and complexity when learning underarm precision throwing

Learning precision ball throwing was mostly studied to explore the early rapid improvement of accuracy, with poor attention on possible adaptive processes occurring later when the rate of improvement is reduced. Here, we tried to demonstrate that the strategy to select angle, speed and height at ball release can be managed during the learning periods following the performance stabilization. To this aim, we used a multivariate linear model with angle, speed and height as predictors of changes in accuracy. Participants performed underarm throws of a tennis ball to hit a target on the floor, 3.42 m away. Two training sessions (S1, S2) and one retention test were executed. Performance accuracy increased over the S1 and stabilized during the S2, with a rate of changes along the throwing axis slower than along the orthogonal axis. However, both the axes contributed to the performance changes over the learning and consolidation time. A stable relationship between the accuracy and the release parameters was observed only during S2, with a good fraction of the performance variance explained by the combination of speed and height. All the variations were maintained during the retention test. Overall, accuracy improvements and reduction in throwing complexity at the ball release followed separate timing over the course of learning and consolidation.     

Inter-letter spacing,inter-word spacing,and font with dyslexia-friendly features: testing text readability in people with and without dyslexia

Over the last years, several studies have suggested a possible link between dyslexia and deficits in low-level visual processing (e.g., excessive crowding). At the same time, specially designed “dyslexia-friendly” fonts appeared on the market. This class of fonts presents two main features: the particular graphic characteristics of the letterform designed to avoid confusion between similarly shaped letters, and wider inter-letter and inter-word spacing to limit crowding. The literature testing the efficacy of “dyslexia-friendly” fonts in improving reading accuracy and increasing reading speed is controversial. We evaluated the impact of letterform (with vs. without dyslexia-friendly graphic features), inter-letter spacing (standard vs. increased), and inter-word spacing (standard vs. increased) on reading accuracy and speed. Two groups of 64 children each, with and without dyslexia, read aloud 8 equivalent texts. The data collected failed to show any effect from the letterform. As regards spacing, the data showed that reading speed is impaired by an increase in inter-letter spacing not combined with an adequate increase in inter-word spacing.     

Three-feature model to reproduce the topology of citation networks and the effects from authors’ visibility on their h-index

Various factors are believed to govern the selection of references in citation networks, but a precise, quantitative determination of their importance has remained elusive. In this paper, we show that three factors can account for the referencing pattern of citation networks for two topics, namely “graphenes” and “complex networks”, thus allowing one to reproduce the topological features of the networks built with papers being the nodes and the edges established by citations. The most relevant factor was content similarity, while the other two – in-degree (i.e. citation counts) and age of publication – had varying importance depending on the topic studied. This dependence indicates that additional factors could play a role. Indeed, by intuition one should expect the reputation (or visibility) of authors and/or institutions to affect the referencing pattern, and this is only indirectly considered via the in-degree that should correlate with such reputation. Because information on reputation is not readily available, we simulated its effect on artificial citation networks considering two communities with distinct fitness (visibility) parameters. One community was assumed to have twice the fitness value of the other, which amounts to a double probability for a paper being cited. While the h-index for authors in the community with larger fitness evolved with time with slightly higher values than for the control network (no fitness considered), a drastic effect was noted for the community with smaller fitness.     

Book reviews

Mobile technologies are becoming ubiquitous in education, yet the wider implications of this phenomenon are not well understood. The paper discusses how mobile lifelong learning (mLLL) may be defined, and the challenges of forging a suitable definition in an ever-shifting technological and socio-economic landscape. mLLL appears as a ubiquitous concept that puts together mobile learning, essentially an ensemble of didactic practices based on the use of mobile technologies, and lifelong learning, a general vision of education in the knowledge society. Starting from the results of an EU-funded project, MOTILL, the paper situates mLLL within the more complex framework of the network society. This illuminates the difficulties in formulating a comprehensive definition, but also the relevance of this concept in the future of learning. We conclude that the future of mLLL can be understood only as a 360 degree vision that is able to take into account a range of pedagogical, managerial, political and ethical issues.     

Children’s and adolescents’ moral emotion attributions and judgements about exclusion of peers with hearing impairments

Children and adolescents with hearing impairments are at risk of being excluded from activities with hearing peers. Moral emotion attributions may represent important indicators for children’s identification with the moral norm not to exclude peers based on disability. Against this background, we investigated how 10-, 12- and 15-year-olds (N?=?215) feel and judge about social exclusion of peers with hearing impairments. Emotion attributions and moral judgements were assessed using four different hypothetical scenarios about the exclusion of peers with hearing impairments (school vs. leisure time, group vs. dyad). Moreover, children’s and adolescents’ inclusive behaviour was assessed by a peer nomination procedure. Results revealed that moral emotion attributions differed as a function of exclusion context and grade. Moreover, participants with inclusive behaviour attributed moral emotions more often than participants with less inclusive behaviour. Implications of the results for moral education are discussed.