17 research outputs found

    citizen of Germany accepted on the recommendation of

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    ii Ubiquitous computing has the goal of enhancing computer use by making many computers available throughout the physical environment, and thus providing the technical and conceptual means for enabling anytime, anywhere, anyhow computing. The technical realization of this vision has become feasible owing to recent advances in miniaturization and embedded computing technologies, which enable the integration of diverse computing capabilities into manifold everyday objects and devices. The multitude and diversity of computerized entities that are part of ubiquitous computing systems imply a number of technical challenges. On one side, the differences in form factors, functionality, and technical capabilities result in a great level of diversity of hardware and software, and a distinct heterogeneity in capabilities. Further, ubiquitous computing systems in general are often highly decentralized, featuring an exceptionally high volatility of cooperative relationships and topologie

    Longitudinal tracking of academic progress during teacher preparation

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    Background. Given that the ultimate academic goal of many education systems in the developed world is for students to graduate from college, grades have a considerable bearing on how effective colleges are in meeting their primary objective. Prior academic performance informs predominantly the selection and retention of teacher candidates. However, there remains a dearth of evidence linking academic performance with outcomes in teacher preparation or the workplace. Aim. This study examined pre-service teachers’ trajectories of academic growth during teacher preparation. Sample. The sample comprised 398 pre-service teachers – 282 (70.8%) males and 116 (29.1%) females. Method. Academic growth was measured across eight time points over the course of 4 years. Pre-service teachers’ academic growth was analysed using linear and nonlinear latent growth models. Results. Results indicate that academic growth was quadratic and, over time, decelerated, with no evidence of the Matthew effect or the compensatory effect. There was evidence of a connection between prior academic attainment and current grades. Conclusion. Greater attention to academic growth during the college years, and particularly among pre-service teachers, may enable greater achievement support for student

    Effect of performance level on pacing strategy during a 10-km running race

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    The aim of this study was to examine the influence of the performance level of athletes on pacing strategy during a simulated 10-km running race, and the relationship between physiological variables and pacing strategy. Twenty-four male runners performed an incremental exercise test on a treadmill, three 6-min bouts of running at 9, 12 and 15 km h−1, and a self-paced, 10-km running performance trial; at least 48 h separated each test. Based on 10-km running performance, subjects were divided into terziles, with the lower terzile designated the low-performing (LP) and the upper terzile designated the high-performing (HP) group. For the HP group, the velocity peaked at 18.8 ± 1.4 km h−1 in the first 400 m and was higher than the average race velocity (P 0.05) and this initial velocity was not different from LP average racing velocity (14.5 ± 0.7 km h−1). The velocity then decreased non-significantly until 9,600 m (P > 0.05), followed by an increase at the end (P < 0.05). The peak treadmill running velocity (PV), running economy (RE), lactate threshold (LT) and net blood lactate accumulation at 15 km h−1 were significantly correlated with the start, middle, last and average velocities during the 10-km race. These results demonstrate that high and low performance runners adopt different pacing strategies during a 10-km race. Furthermore, it appears that important determinants of the chosen pacing strategy include PV, LT and RE

    Neurophysiological Determinants of Theoretical Concepts and Mechanisms Involved in Pacing

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    <p>Fatigue during prolonged exercise is often described as an acute impairment of exercise performance that leads to an inability to produce or maintain a desired power output. In the past few decades, interest in how athletes experience fatigue during competition has grown enormously. Research has evolved from a dominant focus on peripheral causes of fatigue towards a complex interplay between peripheral and central limitations of performance. Apparently, both feedforward and feedback mechanisms, based on the principle of teleoanticipation, regulate power output (e. g. speed) during a performance. This concept is called 'pacing' and represents the use of energetic resources during exercise, in a way such that all energy stores are used before finishing a race, but not so far from the end of a race that a meaningful slowdown can occur.</p><p>It is believed that the pacing selected by athletes is largely dependent on the anticipated exercise duration and on the presence of an experientially developed performance template. Most studies investigating pacing during prolonged exercise in ambient temperatures, have observed a fast start, followed by an even pace strategy in the middle of the event with an end sprint in the final minutes of the race. A reduction in pace observed at commencement of the event is often more evident during exercise in hot environmental conditions. Further, reductions in power output and muscle activation occur before critical core temperatures are reached, indicating that subjects can anticipate the exercise intensity and heat stress they will be exposed to, resulting in a tactical adjustment of the power output. Recent research has shown that not only climatic stress but also pharmacological manipulation of the central nervous system has the ability to cause changes in endurance performance. Subjects seem to adapt their strategy specifically in the early phases of an exercise task. In high-ambient temperatures, dopaminergic manipulations clearly improve performance. The distribution of the power output reveals that after dopamine reuptake inhibition, subjects are able to maintain a higher power output compared with placebo. Manipulations of serotonin and, especially, noradrenaline, have the opposite effect and force subjects to decrease power output early in the time trial. Interestingly, after manipulation of brain serotonin, subjects are often unable to perform an end sprint, indicating an absence of a reserve capacity or motivation to increase power output. Taken together, it appears that many factors, such as ambient conditions and manipulation of brain neurotransmitters, have the potential to influence power output during exercise, and might thus be involved as regulatory mechanisms in the complex skill of pacing.</p>

    Phylogeny as a Proxy for Ecology in Seagrass Amphipods: Which Traits Are Most Conserved?

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    Increasingly, studies of community assembly and ecosystem function combine trait data and phylogenetic relationships to gain novel insight into the ecological and evolutionary constraints on community dynamics. However, the key to interpreting these two types of information is an understanding of the extent to which traits are phylogenetically conserved. In this study, we develop the necessary framework for community phylogenetics approaches in a system of marine crustacean herbivores that play an important role in the ecosystem functioning of seagrass systems worldwide. For 16 species of amphipods and isopods, we (1) reconstructed phylogenetic relationships using COI, 16S, and 18S sequences and Bayesian analyses, (2) measured traits that are potentially important for assembling species between and within habitats, and (3) compared the degree to which each of these traits are evolutionarily conserved. Despite poor phylogenetic resolution for the order Amphipoda as a whole, we resolved almost all of the topology for the species in our system, and used a sampling of ultrametric trees from the posterior distribution to account for remaining uncertainty in topology and branch lengths. We found that traits varied widely in their degree of phylogenetic signal. Body mass, fecundity, and tube building showed very strong phylogenetic signal, and temperature tolerance and feeding traits showed much less. As such, the degree of signal was not predictable based on whether the trait is related to environmental filtering or to resource partitioning. Further, we found that even with strong phylogenetic signal in body size, (which may have large impacts on ecosystem function), the predictive relationship between phylogenetic diversity and ecosystem function is not straightforward. We show that patterns of phylogenetic diversity in communities of seagrass mesograzers could lead to a variety of interpretations and predictions, and that detailed study of trait similarities and differences will be necessary to interpret these patterns
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