442 research outputs found
DĂ©veloppement d'un protocole dâĂ©valuation et dâun programme dâentraĂźnement de la capacitĂ© cardiorespiratoire chez des usagers dâun fauteuil roulant manuel
Les usagers dâun fauteuil roulant (FR) manuel ont une capacitĂ© cardiorespiratoire habituellement fortement diminuĂ©e suite Ă aux dĂ©ficiences physiques ayant menĂ© Ă lâincapacitĂ© Ă la marche et Ă leur mode de vie souvent sĂ©dentaire. Cependant, peu d'outils sont disponibles pour l'Ă©valuation et l'entraĂźnement de la capacitĂ© cardiorespiratoire spĂ©cifique Ă la propulsion dâun FR manuel. Les objectifs principaux de cette thĂšse Ă©taient 1) de proposer et d'Ă©valuer un protocole dâĂ©preuve dâeffort en FR manuel sur un tapis roulant motorisĂ© et 2) dâĂ©tudier la faisabilitĂ©, la sĂ©curitĂ© et les effets dâun entraĂźnement cardiorespiratoire par intervalles Ă haute intensitĂ© en FR manuel effectuĂ© dans la communautĂ©. Trois projets distincts font partie de cette thĂšse. Projet #1 - Exigences cardiorespiratoires lors de la propulsion d'un FR manuel sur un tapis roulant motorisĂ©: 17 usagers d'un FR manuel ont effectuĂ© 12 essais randomisĂ©s de propulsion composĂ©s d'une combinaison d'une pente (0°, 2,7°, 3,6° et 4,8°) et d'une vitesse (0,6, 0,8 et 1,0 m/s) sur un tapis roulant motorisĂ©. Les rĂ©ponses cardiorespiratoires ont Ă©tĂ© mesurĂ©es et l'effet de la pente et de la vitesse sur celles-ci fut calculĂ©. Un nouveau protocole dâĂ©preuve dâeffort fut proposĂ© en se basant sur l'effet de la pente et de la vitesse sur la consommation d'oxygĂšne (VO2). Projet #2 - QualitĂ©s psychomĂ©triques de lâĂ©preuve dâeffort : Au total 28 usagers d'un FR manuel ont participĂ© Ă ce projet. La fidĂ©litĂ© test-retest et le changement minimal dĂ©tectable ont Ă©tĂ© quantifiĂ©s en comparant les rĂ©ponses cardiorespiratoires maximales mesurĂ©es lors de deux Ă©preuves dâeffort sur tapis roulant effectuĂ©es lors dâoccasions diffĂ©rentes. La validitĂ© concomitante des rĂ©ponses cardiorespiratoires maximales mesurĂ©es lors de lâĂ©preuve sur tapis roulant a Ă©tĂ© vĂ©rifiĂ©e en les comparant avec celles obtenues lors dâune Ă©preuve dâeffort sur un ergocycle pour les membres supĂ©rieurs. Projet #3- Programme d'entraĂźnement: Onze usagers d'un FR manuel ont Ă©tĂ© rĂ©partis alĂ©atoirement entre un groupe effectuant un programme d'entraĂźnement cardiorespiratoire par intervalles Ă haute intensitĂ© (HIIT) (N=6) et un groupe effectuant un programme d'entraĂźnement cardiorespiratoire continu Ă intensitĂ© modĂ©rĂ©e (N=5). Ces programmes de 40 minutes/sĂ©ance Ă raison de trois sĂ©ances/semaine pendant six semaines Ă©taient effectuĂ©s en FR manuel dans la communautĂ© sous la supervision indirecte d'un physiothĂ©rapeute. La faisabilitĂ©, la sĂ©curitĂ© et l'efficacitĂ© sur l'amĂ©lioration de la capacitĂ© cardiorespiratoire et de la force des membres supĂ©rieurs ont Ă©tĂ© mesurĂ©es et comparĂ©es entre les deux programmes. Les rĂ©sultats du projet #1 ont dĂ©montrĂ© que les rĂ©ponses cardiorespiratoires augmentaient avec lâaugmentation de la pente ou de la vitesse du tapis roulant pour presque toutes les conditions. LâĂ©quation de prĂ©diction de la VO2 a permis de dĂ©velopper un protocole dâĂ©preuve dâeffort en propulsion dâun FR sur un tapis roulant motorisĂ© fidĂšle et valide pour Ă©valuer la capacitĂ© cardiorespiratoire des usagers dâun FR manuel. Aussi, le programme dâentraĂźnement HIIT sâest avĂ©rĂ© sĂ©curitaire lorsquâeffectuĂ© dans la communautĂ© bien que des prĂ©cautions doivent ĂȘtre prises lorsque les individus prĂ©sentent de la douleur aux membres supĂ©rieurs. De plus, les routes bien entretenues et les endroits peu achalandĂ©s sont des endroits sĂ©curitaires et apprĂ©ciĂ©s pour lâentraĂźnement en FR manuel. Finalement, lâefficacitĂ© du programme dâentraĂźnement HIIT nâa pas Ă©tĂ© dĂ©montrĂ©e aprĂšs six semaines dâentraĂźnement, mais les amĂ©liorations subjectives rapportĂ©es par les participants appuient sa pertinence.Manual wheelchair (MWC) users usually have a strongly reduced cardiorespiratory capacity due to both the physical disabilities which brought the need for a wheelchair and to their often sedentary lifestyle. However, very few tools are available for the evaluation and the training of the cardiorespiratory fitness aimed specifically at MWC users. The main goals of this thesis were to 1) propose and evaluate a MWC stress test protocol on a motorized treadmill and 2) to study the feasibility, the safety and the impacts of a community-based high-intensity interval MWC cardiorespiratory training. This thesis is composed of three distinct projects. Project #1 â Cardiorespiratory requirements during MWC propulsion on a motorized treadmill: 17 MWC users completed 12 randomized trials composed of a combination of a slope (0°, 2.7°, 3.6° and 4.8°) and a speed (0.6, 0.8 and 1.0 m/s) on a motorized treadmill. The cardiorespiratory responses have been measured and the effects of changes of slope and speed on them have been calculated. A new stress test protocol was then proposed according to the effects of the slope and the speed on oxygen consumption (VO2). Project #2 â Psychometric properties of the stress test: A total of 28 MWC users took part to this project. The test-retest reliability and the minimal detectable change (MDC) were quantified by comparing the maximal cardiorespiratory responses measured during two stress tests completed on two separate occasions. The verification of the concurrent validity was done by comparing the maximal cardiorespiratory responses measured during the treadmill stress tests with those measured during a stress test on an arm crank ergometer. Project #3: Training program: 11 MWC users were randomly assigned to either a group doing a high-intensity interval training (HIIT) (N=6) or a group doing a continuous, moderate-intensity cardiorespiratory training (N=5). These programs lasted 40 minutes/session, 3 days/weeks for a duration of 6 weeks and were executed in a MWC in a community setting under the indirect supervision of a physiotherapist. The feasibility, safety and effectiveness regarding an increase in cardiorespiratory capacity and upper extremity strength were measured and compared between programs. The results of project #1 did show higher cardiorespiratory responses with an increase in the treadmill slope or speed for almost all conditions. The prediction equation for the VO2 allowed for a stress test protocol to be developed and which can be used as a reliable and valid test of the cardiorespiratory capacity on a motorized treadmill for MWC users. Furthermore, the HIIT program was deemed safe while executed in a community setting, while precautions should be taken when individuals have upper extremity pain. Also, well-maintained roads and less crowded areas are popular and safe MWC training places. Finally, the effectiveness of the 6 weeks HIIT training program has not been confirmed, but the subjective improvements reported by the patients support the relevance of the program
La nutrition parentérale modifie le statut et le potentiel redox du glutathion hépatique chez le modÚle néonatal du cochon d'Inde
Mémoire numérisé par la Direction des bibliothÚques de l'Université de Montréal
Role of evaporation rate on the particle organization and crack patterns obtained by drying a colloidal layer
International audienceâ A scientific hurdle in manufacturing solid films by drying colloidal layers is preventing them from fracturing. This paper examines how the drying rate of colloidal liquids influences the particle packing at the nanoscale in correlation with the crack patterns observed at the macroscale. Increasing the drying rate results in more ordered, denser solid structures, and the dried samples have more cracks.Yet, introducing a holding period (at a prescribed point) during the drying protocol results in a more disordered solid structure with significantly less cracks. To interpret these observations, this paper conjectures that a longer drying protocol favors the formation of aggregates. It is further argued that the number and size of the aggregates increase as the drying rate decreases. This results in the formation of a more disordered, porous film from the viewpoint of the particle packing, and a more resistant film, i.e. less cracks, from the macroscale viewpoint
La perception des diplĂŽmĂ©s dâune Ă©cole des sciences de lâactivitĂ© physique du dĂ©veloppement de leurs compĂ©tences professionnelles en physiothĂ©rapie : une Ă©tude de cas
Which trunk inclination directions best predict multidirectional-seated limits of stability among individuals with spinal cord injury?
Objective: To determine which trunk inclination directions most accurately predict multidirectional-seated limits of stability among individuals with spinal cord injury (SCI). Design: Predictive study using cross-sectional data. Setting: Pathokinesiology Laboratory. Participants: Twenty-one individuals with complete or incomplete sensorimotor SCI affecting various vertebral levels participated in this study. Interventions: Participants were instructed to lean their trunk as far as possible in eight directions, separated by 45°intervals, while seated on an instrumented chair with their feet positioned on force plates. Outcomes measures: Eight direction-specific stability indices (DSIs) were used to define an overall stability index (OSI) (limits of stability). Results: All DSIs significantly correlated with the OSI (r = 0.816-0.925). A protocol that only tests the anterior, left postero-lateral, and right lateral trunk inclinations accurately predicts multidirectional-seated postural stability (R 2 = 0.98; P < 0.001). Conclusion: Multidirectional-seated postural stability can be predicted almost perfectly by evaluating trunk inclinations performed toward the anterior, left postero-lateral, and right lateral directions
La méthode PadovanŸ de réorganisation neurofonctionnelle auprÚs des enfants présentant un trouble de l'acquisition de la coordination : une étude exploratoire mixte
Introduction. Le trouble de lâacquisition de la coordination (TAC) touche environ 6% des enfants. La cause exacte du TAC demeure mĂ©connue, mais les donnĂ©es probantes actuelles issues de la recherche dĂ©montrent la prĂ©sence dâun dysfonctionnement neurologique. La mĂ©thode PadovanÂź de rĂ©organisation neurofonctionnelle est une intervention qui cible ce type de dysfonctionnement et qui est utilisĂ©e cliniquement par des thĂ©rapeutes, dont des ergothĂ©rapeutes, dans divers pays. Ă ce jour, aucune Ă©tude nâa documentĂ© les types de changements possible de cette intervention chez les enfants prĂ©sentant un TAC.
Objectif. Cette Ă©tude vise Ă explorer les types de changement de la mĂ©thode PadovanÂź chez des enfants dâĂąge scolaire ayant un TAC, en vue de proposer un premier modĂšle de changement.
MĂ©thode. Une Ă©tude de cas multiples utilisant une mĂ©thode mixte a Ă©tĂ© rĂ©alisĂ©e afin d'obtenir des information quant aux capacitĂ©s des enfants et leur participation dans diverses habitudes de vie. Pour chaque cas (n = 5), les donnĂ©es ont Ă©tĂ© recueillies Ă partir dâentrevues semi-dirigĂ©es auprĂšs des parents (donnĂ©es qualitatives) et dâanalyses documentaires de dossiers ergothĂ©rapiques (donnĂ©es qualitatives et quantitatives).
RĂ©sultats. Les rĂ©sultats suggĂšrent des amĂ©liorations concernant plusieurs capacitĂ©s, incluant les activitĂ©s motrices, lâĂ©criture manuelle et lâestime de soi, ainsi que dans la participation dans les soins personnels, lâĂ©ducation et les loisirs.
Conclusion. ConsidĂ©rant ces rĂ©sultats, des Ă©tudes expĂ©rimentales devraient ĂȘtre menĂ©es pour Ă©valuer lâefficacitĂ© de la mĂ©thode PadovanÂź chez les enfants ayant un TAC
Cerebrospinal fluid p-tau231 as an early indicator of emerging pathology in Alzheimer's disease
Background: Phosphorylated tau (p-tau) epitopes in cerebrospinal fluid (CSF) are accurate biomarkers for a pathological and clinical diagnosis of Alzheimer's disease (AD) and are seen to be increased in preclinical stage of the disease. However, it is unknown if these increases transpire earlier, prior to amyloid-beta (AÎČ) positivity as determined by position emission tomography (PET), and if an ordinal sequence of p-tau epitopes occurs at this incipient phase. Methods: We measured CSF concentrations of p-tau181, p-tau217 and p-tau231 in 171 participants across the AD continuum who had undergone AÎČ ([18F]AZD4694) and tau ([18F]MK6240) position emission tomography (PET) and clinical assessment. Findings: All CSF p-tau biomarkers were accurate predictors of cognitive impairment but CSF p-tau217 demonstrated the largest fold-changes in AD patients in comparison to non-AD dementias and cognitively unimpaired individuals. CSF p-tau231 and p-tau217 predicted AÎČ and tau to a similar degree but p-tau231 attained abnormal levels first. P-tau231 was sensitive to the earliest changes of AÎČ in the medial orbitofrontal, precuneus and posterior cingulate before global AÎČ PET positivity was reached. Interpretation: We demonstrate that CSF p-tau231 increases early in development of AD pathology and is a principal candidate for detecting incipient AÎČ pathology for therapeutic trial application
Holistic Processing of Words Modulated by Reading Experience
Perceptual expertise has been studied intensively with faces and object categories involving detailed individuation. A common finding is that experience in fulfilling the task demand of fine, subordinate-level discrimination between highly similar instances is associated with the development of holistic processing. This study examines whether holistic processing is also engaged by expert word recognition, which is thought to involve coarser, basic-level processing that is more part-based. We adopted a paradigm widely used for faces â the composite task, and found clear evidence of holistic processing for English words. A second experiment further showed that holistic processing for words was sensitive to the amount of experience with the language concerned (native vs. second-language readers) and with the specific stimuli (words vs. pseudowords). The adoption of a paradigm from the face perception literature to the study of expert word perception is important for further comparison between perceptual expertise with words and face-like expertise
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