Effects of Heartwood Inhabiting Fungi on Thujaplicin Content and Decay Resistance of Western Redcedar (Thuja Plicata Donn.)

Western redcedar (Thuja plicata Donn.) outer heartwood blocks from a mature and an immature tree, inoculated with fungi commonly isolated from stained heartwood, had a thujaplicin content of less than 6% and a hot water solubility of about one-half that of controls after 10 weeks of exposure. Decay resistance of blocks from the mature tree was greatly reduced following exposure to the staining fungi. Naturally stained heartwood also had low thujaplicin content, but its decay resistance remained high in the same test

Attentional processes of high-skilled soccer players with congenital hemiparesis: Differences related to the side of the hemispheric lesion

Contains fulltext : 72909.pdf (publisher's version ) (Closed access)We investigated attentional processes that support the performance of high-skilled soccer players with hemiparetic cerebral palsy. Participants (N = 10) dribbled a slalom course as quickly and accurately as possible under two attentional-focus manipulation conditions. In the task-relevant focus condition, they attended to the foot that was in contact with the ball, whereas in the task-irrelevant focus condition, they monitored a series of words played on a tape. The time taken to complete the slalom course was registered. Performances of individuals with left and right hemiparesis were compared to explore differential effects of hemispheric lesion. The high-skilled players with congenital hemiparesis showed similar attentional-focus effects as those previously reported in the literature for high-skilled players without neurological disorders (Beilock et al., 2002; Ford et al., 2005). Task-relevant focus increased dribbling time, whereas a task-irrelevant focus did not result in a significant change in dribbling time. These findings generalized to each of the five participants with left hemiparesis (i.e., damage to the right hemisphere). By contrast, the effects of a task-relevant focus were less consistent for participants with right hemiparesis (i.e., left-hemisphere damage). This corroborates suggestions that the reinvestment of procedural knowledge is a left-lateralized function. The implications for the training of individuals with congenital brain damage are discussed

The staircase method: integrals for periodic reductions of integrable lattice equations

We show, in full generality, that the staircase method provides integrals for mappings, and correspondences, obtained as traveling wave reductions of (systems of) integrable partial difference equations. We apply the staircase method to a variety of equations, including the Korteweg-De Vries equation, the five-point Bruschi-Calogero-Droghei equation, the QD-algorithm, and the Boussinesq system. We show that, in all these cases, if the staircase method provides r integrals for an n-dimensional mapping, with 2r<n, then one can introduce q<= 2r variables, which reduce the dimension of the mapping from n to q. These dimension-reducing variables are obtained as joint invariants of k-symmetries of the mappings. Our results support the idea that often the staircase method provides sufficiently many integrals for the periodic reductions of integrable lattice equations to be completely integrable. We also study reductions on other quad-graphs than the regular 2D lattice, and we prove linear growth of the multi-valuedness of iterates of high-dimensional correspondences obtained as reductions of the QD-algorithm.Comment: 40 pages, 23 Figure

Involutivity of integrals for sine-Gordon, modified KdV and potential KdV maps

Closed form expressions in terms of multi-sums of products have been given in \cite{Tranclosedform, KRQ} of integrals of sine-Gordon, modified Korteweg-de Vries and potential Korteweg-de Vries maps obtained as so-called $(p,-1)$-traveling wave reductions of the corresponding partial difference equations. We prove the involutivity of these integrals with respect to recently found symplectic structures for those maps. The proof is based on explicit formulae for the Poisson brackets between multi-sums of products.Comment: 24 page

Motor skill learning in groups: Some proposals for applying implicit learning and self-controlled feedback

Contrary to researchers' current focus on individual motor skill learning, in institutional settings such as physical education and sports motor skill learning is often taught in groups. In these settings, there is not only the interaction between teacher and learner (analogous to research), but also the many interactions between the learners in the group. In this paper, we discuss the pitfalls of applying research findings without taking into account the different dynamics that the interactions between group members bring about. To this end, we especially discuss implicit motor learning and self-controlled feedback, as these have recently been hailed as being particularly effective for increasing motor skill and self-efficacy. Proposals are provided to adopt these methods for motor skill learning in groups. This is not only relevant for practitioners in physical education and sports, but also establishes an agenda for research

Exploring the thresholds of vision for perception and action

Based upon evidence that vision for action has quicker access to visual information than vision for perception, we hypothesized that the two systems may have differentiated visual thresholds. There is also evidence that, unlike vision for perception, vision for action is insensitive to cognitive dual-task interference. Using visual masking, we determined the visual thresholds of 15 participants in a perception task, an action task and an action plus concurrent cognitive secondary task. There was no difference in threshold between the perception task and the action task, but the action plus concurrent secondary task was accompanied by a greater visual threshold than both the perception task and the action task alone, indicating dual-task interference. The action task was thus most likely informed by vision for perception. The implications of these results are reviewed in the context of recent discussions of the two visual systems model. © 2012 Human Kinetics, Inc.published_or_final_versio

The effect of goalkeepers adopting Muller-Lyer postures

Poster 5 - Motor Control: Neural Correlates/Sensorimotor/Motor Practice and Observation: no. 57The posture that a goalkeeper assumes can influence perceptions of his or her size and the motor behavior of an opponent. Van der Kamp & Masters (2008) showed that postures that mimicked an amputated Muller-Lyer illusion in a wings-out/arms-up configuration resulted in larger estimates of goalkeeper height than a wings-in/arms-down configuration. Furthermore, when participants threw to score in a handball goal, the shots were placed further from the arms-up goalkeeper, presumably because he was thought capable of covering a greater area of the goal. We aimed to verify that throwing behaviour was related to (mis-)perceptions of goalkeeper height and, by association, goalkeeper reach. A 1.9 m animated representation of a goalkeeper was projected onto a blank screen. The goalkeeper was shown in an arms-up (45 degrees above horizontal), arms-out (horizontal), or arms-down (45 degrees below horizontal) posture. The 3 postures were each shown 10 times in a random order. For each presentation 34 participants made two estimates of the goalkeeper’s maximum static reach, which was defined as the position of middle finger of the goalkeeper in the arms-out posture. Estimates were made by aiming a laser pointer and throwing a ball. The horizontal displacements of the aiming and throwing estimates from the actual position of middle finger (75 cm from the midline of the body) were measured. For the horizontal displacement measure, there was no significant difference between aiming and throwing estimates (p > .05), but a significant effect of posture, F(2, 66) = 10.1, p <.01. Participants perceived the hand closer to the midline of the body in the arms-down posture (67.4 cm) than the arms-up posture (75.2 cm). The findings corroborate previous work in suggesting that the goalkeeper can influence perceptions of his maximum reach and the motor behaviour of an opponent by adopting illusory postures. Further investigations need to address whether the effects are also mediated by hand position or perceptions of arm length rather than body height.published_or_final_versionThe 2010 Conference of the North American Society for the Psychology of Sport and Physical Activity (NASPSPA 2010), Tucson, AZ., 10-12 June 2010. In Journal of Sport and Exercise Psychology, 2010, v. 32 suppl., p. S12