Facilitators and obstacles to success for students with disabilities

Titre de l'écran-titre (visionné le 22 avril 2009).Bibliogr.Résultats d'une recherche sur les obstacles et les facteurs facilitants la réussite scolaire des personnes handicapées au niveau collégial mettant en relief le profil de ces étudiants ainsi que les similarités et les différences avec les étudiants sans handicap; rappel des principes de l'accessibilité universelle en pédagogie suivi de recommandations

Facilitateurs et obstacles à la réussite des étudiants handicapés

Titre de l'écran-titre (visionné le 25 août 2008).Bibliogr

Elevated Mitochondrial Bioenergetics and Axonal Arborization Size Are Key Contributors to the Vulnerability of Dopamine Neurons

SummaryAlthough the mechanisms underlying the loss of neurons in Parkinson’s disease are not well understood, impaired mitochondrial function and pathological protein aggregation are suspected as playing a major role. Why DA (dopamine) neurons and a select small subset of brain nuclei are particularly vulnerable to such ubiquitous cellular dysfunctions is presently one of the key unanswered questions in Parkinson’s disease research. One intriguing hypothesis is that their heightened vulnerability is a consequence of their elevated bioenergetic requirements. Here, we show for the first time that vulnerable nigral DA neurons differ from less vulnerable DA neurons such as those of the VTA (ventral tegmental area) by having a higher basal rate of mitochondrial OXPHOS (oxidative phosphorylation), a smaller reserve capacity, a higher density of axonal mitochondria, an elevated level of basal oxidative stress, and a considerably more complex axonal arborization. Furthermore, we demonstrate that reducing axonal arborization by acting on axon guidance pathways with Semaphorin 7A reduces in parallel the basal rate of mitochondrial OXPHOS and the vulnerability of nigral DA neurons to the neurotoxic agents MPP+ (1-methyl-4-phenylpyridinium) and rotenone. Blocking L-type calcium channels with isradipine was protective against MPP+ but not rotenone. Our data provide the most direct demonstration to date in favor of the hypothesis that the heightened vulnerability of nigral DA neurons in Parkinson’s disease is directly due to their particular bioenergetic and morphological characteristics

Infinite families of superintegrable systems separable in subgroup coordinates

A method is presented that makes it possible to embed a subgroup separable superintegrable system into an infinite family of systems that are integrable and exactly-solvable. It is shown that in two dimensional Euclidean or pseudo-Euclidean spaces the method also preserves superintegrability. Two infinite families of classical and quantum superintegrable systems are obtained in two-dimensional pseudo-Euclidean space whose classical trajectories and quantum eigenfunctions are investigated. In particular, the wave-functions are expressed in terms of Laguerre and generalized Bessel polynomials.Comment: 19 pages, 6 figure

Creative haptics: an evaluation of a haptic tool for non-sighted and visually impaired design students, studying at a distance

Design students who are blind or sight-impaired face distinct challenges when studying a visually centric discipline such as design practice. Students who are sighted use computer-aided design (CAD) which is presented via high definition using a PC mouse. However, design students who are blind or sight-impaired are not able to use visual display technology; therefore, this creates a barrier to access for this community. The aim of this study is to present a haptic prototype trial (Haptic Application Prototype Test [HAPT]) designed to assist design students who are blind/sight-impaired to interact with prototype assembly at the Open University (OU). The study specifically assessed the user feedback and the efficacy of access to CAD interface through the affordances of the haptic interface. The experiment included two groups of participants: one group included students who were blind and sight-impaired and the second group students who were classed fully sighted. Both groups were tested in two conditions of haptic engagement – manual and virtual. The parameters examined were (a) time – set at an industry-recognized time taken to assemble a ‘sketch model’ or prototype, and (b) ncollision – the number of collisions created by a collision algorithm which calculated any random collisions with the virtual environment or objects therein. Quantitative results showed that there was little statistical difference between time and a between-group test. From this we can imply that the haptic interface had offered equal access to CAD for people in the trial who were sighted and blind/sight-impaired indiscriminate of their sight acuity. Further future work using HAPT could be developed to a wider audience and a larger more diverse range of sight-impaired users. Future work will focus on new explorations of teaching using of haptics for greater immersion for distance learners at the OU science, technology, engineering and mathematics (STEM) labs