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Research was conducted that culminated in the merging of the objectives of two tools: predetermined motion time systems and posture recording. This dissertation reports the development and testing of a computerized tool-the Work and Posture Analysis Sequence Technique (WAPAST)-used to collect methods, postural, and work measurement data. From the data collected, one can determine the method used to complete an activity by task identification, the time it takes to complete each task, as well as the time to complete an entire activity, and the postural considerations for each task and for the overall activity. The tool is based on the Maynard Operations Sequence Technique (MOST) with some characteristics of the Ovako Working Posture Analysis System (OWAS). Criteria established were speed of completion, accuracy, and reliability. A validation study was conducted to assess the data collected with WAPAST against data collected with known, validated tools. The study was an experiment that had several subjects use WAPAST to analyze videotaped work activities while several other subjects used MOST or OW AS to analyze the same videotaped activities. The data collected with WAPAST were compared with the data collected with MOST and OWAS. The work measurement data collected with WAPAST were found to be both accurate and reliable, but the postural data were not. Times to cornplete applications were extensive. Recommendations are given for improving the tool, which include a different way of recording postural data and expanding the limitations of the tool. / Ph. D.

Workers are challenged by the increasingly complex multitasking environments they experience. To interact effectively with these environments, they must avoid overload. When workers get overloaded (when their mental demands exceed the resource capacity) quality drops, performance degrades, and safety suffers. What is largely unknown, however, is whether these results translate to postural tasks. Postural stability exhibits an entirely different set of challenges: injury, the danger of slips and falls, and risks associated with aging workers or those who have mental or physical challenges. An assembly line worker, for example, must assume different postures, interact with the product in some way, and react to visual and auditory alarms. Mistakes could be dangerous. It is clearly important, then, to understand the interactive effects of mental and postural workload. The goal of this research was to quantify the effects of mental and postural demands on overall workload. To accomplish this, we implemented three studies that were designed to capture the synergistic effects of different task types on overall workload and compare different types of workload measures against each other to help further design research in the area. We designed a dual-task mental/postural protocol to test the differential effects of a series of cognitive demands found in dual-task postural studied. The results of the first study depict a clear picture: the addition of an auditory task to unstable seating decreases postural sway. Based solely on this result, it might be concluded that workload did not increase. Using the same protocol while measuring mental workload however, we found that workload did in fact increase both subjectively and objectively, even when similar postural benefit was found. Even as performance seemed to improve, the participant moved nearer to possible overload and performance decrement (a condition we did not induce in this research). Based on the differences found between the different measures, we believe the importance of measuring overall workload as well as individual task performance in cognitive/postural dual-task research is very high. / Ph. D.

A diagrammatic method of recording static human postures was developed. Criteria established for the recording method were speed of completion, accuracy, reliability, ease of use, and universal applicability. Design of the recording method was based on cognitive, perceptual, and anthropometric considerations related to these criteria, and a review of existing posture recording methods. A validation study was carried out to assess the recording method against the established criteria. The study entailed having several subjects use the recording method to record various postures and a comparison of their results. The recording method proved to be moderately accurate for the postures studied. The recording method should prove useful in providing a record of the general posture being recorded. However, time required to complete the posture recordings was extensive. Recommendations are given for improving the posture recording method. Among these is a recommendation for more extensive training and practice than was afforded the subjects in this study. Other recommendations have been incorporated into a modified set of recording diagrams. Whether these modifications will improve the recording method remains to be determined. / Master of Science

The human form becomes the bearer of my inspiration, revealing a cosmology within itself, appealing to the idea of understanding the body and implementing its essence into architecture. The lessons found in the tectonic of one's body will assist in discovering an integral logic that may translate in the design of the building. Living organisms inspire architectural posture that generate my architectural ideas. Architecture considered, in a very natural way reflects humans. I try to find a methodology inspired by natural organisms, finding the human body the most beautiful and functional of all natural objects. The structure begins to illustrate the innovation of the materials being employed to a different type of solution to a structural problem. The truth of materials, and honesty in the expression of structure reflect the movement of the object. / Master of Architecture

The visual display terminal (VDT) is an integral part of the modern office. An issue of concern associated with the use of the VDT is maintaining privacy of on-screen materials. Privacy filters are products designed to restrict the viewing angle to documents displayed on a VDT, so that the on-screen material is not visible to persons other than the VDT operator. Privacy filters restrict the viewing angle either by diffraction or diffusion of the light emitted from the VDT. Constrained posture is a human factors engineering problem that has been associated with VDT use. The purpose of this research was to evaluate whether the use of privacy filters affected: 1) the restriction of postures associated with VDT use, 2) operator performance, and 3) subjective ratings of display issues, posture, and performance. Nine participants performed three types of tasks: word processing, data entry, and Web browsing. Each task was performed under three filter conditions: no filter, diffraction filter, and diffusion filter. Participants were videotaped during the tasks using a camera mounted above the VDT workstation. The videotape was analyzed and horizontal head deviation was measured at 50 randomly selected points during each task. Horizontal head deviation was measured as the angle between an absolute reference line, which bisects the center of the VDT screen, and a reference point located at the center of the participant's head. Standard deviation of head deviation were evaluated across filter type and task type. Accuracy- and/or time-based measures were used to evaluate performance within each task. Participants used a seven-point scale to rate the following: readability, image quality, brightness, glare, posture restriction, performance, and discomfort. The results indicated that the interaction between task and filter type affected the standard deviation of horizontal head deviation (a measure of the average range of horizontal deviation). The standard deviation of horizontal deviation was significantly larger within the Web browsing task under the no filter and diffusion filter conditions as compared to the diffraction filter condition. Filter type affected subjective ratings of the following: readability, image quality, brightness, posture restriction, and discomfort. The diffraction filter resulted in lower readability, image quality, and brightness ratings than the diffusion and no filter conditions. Participants reported that the ability to change postures was significantly decreased by the use of the diffraction filter as compared to the no filter and diffraction filter conditions. The diffraction filter resulted in an increase in reported discomfort as compared to the no filter condition. The interaction between filter and task type affected subjective ratings of performance. Participants reported a decrease in the rating of perceived performance under the diffraction filter / Web browsing condition as compared to the no filter / word processing, diffusion filter / Web browsing, and diffusion filter / data entry conditions. A decrease in the rating of perceived performance was reported in the diffraction filter / data entry condition as compared to the no filter / word processing and diffusion filter / Web browsing conditions. Neither diffraction nor diffusion filter affected performance within any of the tasks, based on the objective performance measures used in the experiment. / Master of Science

Objectifs : Comparer l’efficacité et l'aspect sécuritaire de la rivastigmine sous forme orale et transdermique destinée au traitement des symptômes liés aux instabilités posturales de patients atteints de la démence de la maladie de Parkinson (PDD) et qui sont des candidats pour un inhibiteur de l’acétylcholinestérase. La principale variable de l'étude était le changement de vitesse moyenne du centre de pression (CoP) en position debout après 6 mois de traitement. Les variables secondaires étaient les paramètres structuraux de posturographie dynamique, des échelles d’évaluation cliniques et les effets secondaires nécessitant une réduction de la dose. Méthodes: Des patients avec PDD ont été randomisé dans un ratio de 1 :1 impliquant une prise de rivastigmine orale ou transdermique avec des doses cibles de 6 mg deux fois par jour et 9,5 mg/10 cm2 par jour, respectivement. Les variables dépendantes ont été comparées au départ de l’étude et après 6 mois (comparaisons intra-groupes), de même qu'entre les groupes. Résultats: Dix-neuf patients ont complété l’étude (n=8 orale; n=11 transdermique). Des doses quotidiennes moyennes de 9,4 mg (± 1,5 mg) et 16,4 mg (± 3,6 mg) ont été administrées aux groupes oral et transdermique, respectivement. Le groupe transdermique a démontré une réduction significative de la vitesse moyenne du CoP de 15.8% (timbre: p=0,02; orale: réduction de 10,0%, p=0,16) lors de la condition d'équilibre la plus difficile (yeux fermés en maintenant l'équilibre sur une plateforme mobile synchronisée avec les déplacements du corps). Aucune différence n’a été trouvée entre les groupes (p=0,27). Concernant les paramètres structuraux, des améliorations significatives ont été observées au niveau de la durée moyenne des pics de stabilité de l'équilibre (timbre) et de la distance entre les pics de stabilité (orale) dans la condition d'équilibre la plus difficile. Aucun changement n’a été observé par rapport aux échelles cliniques. Six patients ont eu des effets secondaires mineurs nécessitant une réduction de dose (n=5 orale; n=1 transdermique). Conclusions: La rivastigmine pourrait améliorer certains éléments du contrôle postural de patients atteints de PDD, notamment la vitesse moyenne du CoP en position debout. Les bienfaits sont plus évidents sous les conditions qui challengent davantage l'équilibre. / Objectives: To compare the efficacy and safety of oral and transdermal rivastigmine for postural instability in patients with Parkinson’s disease dementia (PDD) who were candidates for a cholinesterase inhibitor. The primary outcome was the change in mean velocity of the centre of pressure (CoP) after 6 months. Secondary outcomes included structural parameters of dynamic posturography, clinical rating scales and adverse events requiring dose reduction. Methods: Patients with PDD were randomized in a 1:1 ratio to oral or transdermal rivastigmine with target doses of 6 mg twice daily and 9.5 mg/10 cm2 daily, respectively. Outcomes were assessed at baseline and 6 months. Results were compared within and between groups. Results: Nineteen patients completed the study (n=8 oral, n=11 transdermal). Mean daily doses of 9.4 mg (± 1.5 mg) and 16.4 mg (± 3.6 mg) were achieved in the oral and transdermal groups, respectively. The transdermal group demonstrated a significant 15.8% decrease in mean velocity of CoP (patch: p <0.05; oral: 10.0% decrease, p=0.16) in the most difficult scenario (eyes closed with sway-referenced support). There was no difference between groups (p=0.27). For structural parameters, significant improvements were seen in the mean duration of peaks (patch) and inter-peak distance (oral) in the most difficult condition. No changes were observed in clinical rating scales. Six patients experienced non-serious adverse events requiring dose reduction (n= 5 oral; n=1 transdermal). Conclusions: Rivastigmine may improve certain elements of postural control, notably the mean velocity of CoP. Benefits appear to be more obvious under more taxing sensory conditions.

Submitted in partial compliance with the requirements for the Masters’ Degree in Technology: Chiropractic, Department of Chiropractic, Durban University of Technology, Durban, South Africa, 2015. / Research has shown that more than 90% of the scholars, use backpacks, worldwide. The backpack has the ability to transport books, sports equipment and clothing between school and home, climaxing in a capacity that may affect posture. Therefore, it is noted that a backpack, which is not carried correctly, fitted improperly and/or over packed may pose a threat to the scholar’s posture Aim: To determine the effect between a novel and school-issued backpack in terms of postural symmetry measurements (photographic measurements), when compared to no backpack, on high school adolescent standing posture. Method: This research was a quantitative descriptive cross sectional experimental design. Each participating scholar underwent a BMI, height and weight screening, prior to inclusion into the data collection process. One hundred asymptomatic scholars, aged between 12 to 14 years, were recruited using convenience sampling. Thereafter, digital photographic images of each scholar was taken in 3 groups, i.e. no Backpack, with a school-issued backpack (Backpack A) and a novel backpack (Backpack B). These digital photographic images were then uploaded, by the researcher, onto the Posturepro 8 Computer Postural Software System. The objective measurement tool (Posturepro 8 Computer Postural Software System) calculated, in degrees, the postural measurements of the scholars’ neck, shoulder and pelvis, by manually constructing lines (horizontal and vertical) between the anatomical landmarks (bilaterally). IBM SPSS version 21 was used to analyse the data. A two-tailed p value of <0.05 was considered as statistically significant. Parametric summary statistics such as mean and standard deviations were used to describe the outcomes in each group. Postural measurements were compared between the pairs (i.e. no Backpack versus Backpack A, no Backpack versus Backpack B and Backpack A versus Backpack B) using paired sample t-tests. A one sample t-test was used to compare the symmetry measurements to a null hypothesis value of 0. Results: The mean age of the one hundred scholars was 13.5 (± 0.6 SD) years. The age of the scholars ranged between 12 and 14 years. This research was performed to determine which backpack (A or B) performed better in maintaining the scholar’s posture (with no backpack). A direct comparison was performed with no Backpack to that of Backpack A and Backpack B. The comparison for each of the differences closest to zero (‘0’) in the no Backpack, Backpack A and Backpack B groups was performed using a one sample t-test. The values closer to zero (‘0’) indicated a normal postural symmetry. None of the postural symmetry measurements were significantly different from zero in all 3 groups as the mean differences were very close to zero. Therefore, when comparing Backpack A to Backpack B, this research showed that there was no significant differences between the two backpacks when looking at postural symmetry (p=0.05). Conclusion: The trends observed in this study partly supported the claims by the company (‘Improved Postural Alignment for You’) of the novel backpack. The novel backpack (Backpack B) showed significant differences in some instances when assessing other outcome measurements, but showed no significant difference when comparing postural symmetry between the two backpacks. Further studies need to be done incorporating all aspects of postural analysis, and not just postural symmetry measurements.

Mémoire numérisé par la Division de la gestion de documents et des archives de l'Université de Montréal.

Quel rôle joue la gravité dans les représentations internes de l'action ? Au-delà des contraintes d'équilibre, le vecteur gravitaire influence-t-il l'action de façon globale, jusqu'à la perception des mouvements de nos semblables ? Ces questions ont été celles qui ont guidé mes travaux de thèse. L'originalité de notre approche a été de placer l'exécution et la perception de l'action dans un « continuum fonctionnel » s'articulant autour des représentations internes de l'action. Pour ce faire, l'outil de choix qui est commun aux trois expériences de cette thèse est la microgravité (0G). Les expériences de cette thèse ont montré que les représentations internes de l'action se nourrissaient des informations graviceptives pour se construire et s'adapter constamment. Cependant, dans certaines conditions telle que la 0G à court terme, apparaît un ordre de priorité. En effet, le SNC est capable de mettre en place des solutions immédiates et efficaces pour l'exécution, comme en témoigne la repondération sensorielle rapide qui s'opère en 0G dans une tâche d'orientation posturale. Cependant, un temps de latence est observé dans la recalibration des modèles internes sur la base des afférences sensorielles fortement perturbées. C'est ce que nous avons montré grâce à un protocole d'imagerie motrice, mettant en évidence une perte de l'isochronie entre les mouvements exécutés et imaginés en 0G. Enfin, nous avons mis en évidence, chez des sujets sans expérience aucune de microgravité, que la perception du mouvement humain est efficace même lorsque ce dernier est exécuté en apesanteur, bien que des réseaux cérébraux différents soient mis en jeux. / What is the role of gravity in the internal representations of action? Beyond the constraints of balance, does the gravity vector influence the action globally, up to the perception of our peers' movement? These issues have guided my thesis work. The originality of our approach was to place the execution and the perception of action in a "functional continuum" built around the internal representations of the action. To do this, the tool of choice, that is common to all three experiments presented here, is microgravity (0G). The experiments of this thesis showed that the internal representations of action are fed with graviceptive information to build and adapt constantly. However, under certain conditions such as short-term 0G, an order of priority appears. Indeed, the CNS is able to implement immediate and effective solutions, as we demonstrate it with the fast sensorial reweighting observed during a postural orientation task. However, a lag is observed in the recalibration of internal models based on sensory inputs severely disrupted. This is what we have shown through a protocol of motor imagery, showing a loss of isochrony between executed and imagined movements under 0G. Finally, we have demonstrated in subjects without any experience of microgravity, that the perception of human movement is effective even when it is performed in weightlessness, although different cerebral networks are involved.