Accelerometers were used to measure evoked peak limb acceleration (EPLA) for the fourth (index) finger. EPLAs were used to investigate force properties of motor units (MUs) and estimate their numbers in the first dorsal interosseous (FDI) through clustering in the force versus stimulus amplitude relationship. This system was semi-automated using a personal computer with A/D and D/A facilities. Upon repeated excitation, some MUs would potentiate and increase their force contribution by 3 to 4 times. It was found that MU number estimation procedures based on force that do not consider twitch potentiation may be underestimating MU numbers. A disadvantage of using EPLA for MU estimation is that sensitivity may vary between subjects due to finger weight and joint dynamics. / Thesis / Master of Engineering (MEngr)

Abstract Aim The aim of the study was to examine the capability of accelerometers to estimate energy expenditure during high-intensity complex physical activity patterns. Also, to investigate whether placing the monitor on the hip or wrist influenced its prediction ability. Furthermore, the purpose was also to evaluate if there was a significant difference in the aforementioned estimations using data from one axis compared to all three axis combined.     Method A total of 14 subjects, eight men and six women, mean (SD) age of 26, 4 (5,5) years were recruited for the study. The participants performed standardised aerobic exercise while accelerometer data and oxygen uptake was measured simultaneously. Two triaxial accelerometers (Actigraph GT3X) were worn on the hip and wrist during the experiment. Indirect calorimetry, using Oxycon mobile, was chosen as the criterion measure. Validity was determined by comparing accelerometer counts with estimated energy expenditure (EE) in kcal/min, derived from measured oxygen consumption, using bivariate Pearson correlation, linear regression and stepwise regression analyses. Equations were calculated using each participant’s individual regression analyses.   Results The experiment reveals that GT3x presents a moderate correlation (r= 0, 47) for estimating EE from aerobics when worn on the hip and a weak correlation (r = 0.34) when worn on the wrist. However, when combined with the body mass variable, a strong correlation was found between accelerometer data for the hip and EE (r= 0.73). At both positions the vector magnitude (r = 0.47 for the hip and r = 0.34 for the wrist) yielded stronger correlations compared to just using the Y-axis (r = 0.15 for the hip and r= 0.08 for the wrist).     Conclusions In conclusion, this study found that GT3x was not particularly valid for assessing energy expenditure in high intensity complex activities. Wearing the accelerometer on the hip yielded higher correlations compared to wearing it on the wrist. When using the accelerometer for estimations of EE the Vector magnitude is to prefer before the Y-axis solely.

Swallowing dysfunction, or dysphagia, can result from any structural or neurological impairment that affects the swallowing mechanism. Accelerometry is a non-invasive technique that may be used to measure the epidermal vibration signals on a patient’s throat during swallowing. The purpose of this study was to map out the trajectories of the hyoid bone and arytenoids during swallowing to determine if a relationship exists between their trajectories and the signals obtained from an accelerometer placed on a participant’s neck during a scheduled videofluoroscopic swallowing study. Participants included 43 adult patients with neurogenic dysphagia. A software program was created to track the desired anatomy on the videofluoroscopic videos frame-by-frame. The data from the software was then compared to the integrated acceleration data multiple linear regression. The results show that the hyoid and larynx are not always correlated during swallowing and further suggest hyolaryngeal excursion as the primary physiological source of accelerometry.

Swallowing dysfunction, or dysphagia, can result from any structural or neurological impairment that affects the swallowing mechanism. Accelerometry is a non-invasive technique that may be used to measure the epidermal vibration signals on a patient’s throat during swallowing. The purpose of this study was to map out the trajectories of the hyoid bone and arytenoids during swallowing to determine if a relationship exists between their trajectories and the signals obtained from an accelerometer placed on a participant’s neck during a scheduled videofluoroscopic swallowing study. Participants included 43 adult patients with neurogenic dysphagia. A software program was created to track the desired anatomy on the videofluoroscopic videos frame-by-frame. The data from the software was then compared to the integrated acceleration data multiple linear regression. The results show that the hyoid and larynx are not always correlated during swallowing and further suggest hyolaryngeal excursion as the primary physiological source of accelerometry.

The purpose of this study was to assess the effectiveness and user-acceptability of three Mark 3 water pump carriage systems for the Aviation and Forest Fire Management division of the Ontario Ministry of Natural Resources (OMNR). Twenty Ontario Fire Rangers were recruited to wear three different designs of the Mark 3 carriage system (Original, Modified, and OMNR Prototype) through a circuit of tasks that simulated a Fire Ranger’s working environment. Subjective ratings were determined for difficulty of loading/unloading, discomfort, system stability and overall performance after each pump condition with a final ranking questionnaire on the same variables after circuit completion. Two tri-axial accelerometers mounted on each pump and the sternum of each participant provided data for calculation of relative pump-carrier accelerations. Measures were determined for the mean relative accelerations, 50th and 90th percentile acceleration amplitude distributions, and median acceleration frequencies. One-way repeated measures ANOVA with post-hoc comparisons were conducted on the objective and subjective rating data followed by ranking each score to attain a total score. Overall, the OMNR Prototype was ranked as the best system. It received a first place ranking for all subjective variables and a first place ranking in 10/18 objective variables with a second place ranking on 6/18 scores. It was concluded that the OMNR Prototype will be recommended for implementation as the OMNR fire suppression system. However, prior to full implementation, additional in-field evaluations should be conducted. / Thesis (Master, Kinesiology & Health Studies) -- Queen's University, 2010-05-21 15:44:33.548

Orientador: Juliana Regina Peiró / Coorientador: Lina Maria Wehle Gomide / Flávia de Almeida Lucas / José Coprrêa de Lacerda Neto / Resumo: Nosso estudo avaliou as características biomecânicas (comprimento e frequência da passada, deslocamento dorsoventral, potência dorsoventral, propulsão, potência médio lateral e potência total) de potros da raça Mangalarga Marchador, comparando com os melhores animais adultos da propriedade com o objetivo de identificar precocemente características desejáveis da marcha. Foram avaliados doze potros nos primeiros quinze dias de vida e dez adultos, em uma mesma propriedade. A obtenção das variáveis cinemáticas e cinéticas foi realizada com o equipamento de análise de andamento Equimetrix (Centaure Métrix, Fontainebleau, France) e a velocidade acompanhada com uso de GPS preso no braço do treinador. Foi realizada a comparação dos dois grupos, ao passo e à marcha. Nossos resultados demonstraram que ao passo podem ser observadas precocemente nesta raça a frequência e a simetria desde o nascimento e a regularidade a partir do décimo primeiro dia de vida. Em relação à marcha, a regularidade foi o único parâmetro consistente desde o nascimento / Abstract: The aim of this study was to compare the biomechanical characteristics of gait (length and frequency of the gait, dorsoventral displacement, dorsoventral power, propulsion, lateral power mean and total power) of foals and adult animals from Mangalarga Marchador breed to identify early characteristics of gait. Twelve foals were evaluated during the first 15 days of life and the results were compared to the mean values recorded from 10 adult horses. Kinematic and kinetic variables were obtained with Equimetrix (Centaure Métrix, Fontainebleau, France), and speed was monitored using a GPS attached to the trainer's arm. Step and marcha gait analyses were compared between groups. At walk, our results demonstrated that frequency and symmetry are similar to adults and can be observed early in foals since the day of birth whereas regularity is characteristic for this breed from the 11th day of life on. Regarding gait, regularity was the only consistent parameter since birth / Mestre

Psychological well-being occurs when there is an absence of mental disorders and presence of positive states. Given the increasing prevalence of mental disorders, which are thought to have their roots in childhood, improving psychological well-being in children is currently an important area of research. Physical activity has been proposed as a method by which negative states can be reduced and positive states increased, thereby increasing children’s overall psychological well-being and in turn helping to protect against a decline into clinical disorders. Research focusing on physical activity and psychological well-being has mainly used self- reported measurements to assess physical activity, a method which leads to considerable non-differential misclassification that in turn will attenuate associations between physical activity and psychological wellbeing. Few studies have employed more precise, objective measures such as accelerometry. Despite providing a more precise measure of physical activity, a number of limitations are present with the use of accelerometry, specifically concerning the data reduction processes. Various decisions made when handling accelerometer data can result in misclassification of time spent in different intensities of physical activity and can introduce selection bias. The present thesis aims to address how the decisions made during data reduction can affect estimates of physical activity prevalence and alter the observed relationships between physical activity and psychological well-being in children. The first study of this thesis assessed the misclassification of activity intensities occurring as a result of the use of various accelerometer cut-points and the resulting variation in relationships between physical activity and psychological well-being that occurs. Results showed that the use of different cut-points to determine physical activity intensity alters the magnitude of the relationship between physical activity and psychological well-being; relationships were attenuated, with some becoming non-significant. The second study addressed the issue of children’s compliance with wear time requirements over multiple time points; compliance with wear time decreased over time, whilst inclusion and exclusion rules based on minimum wear times introduced selection bias. The use of more lenient wear time criteria, to reduce selection bias, introduced misclassification of physical activity intensities. Further, longitudinal relationships between physical activity and psychological well-being differed depending upon the wear time criteria employed. The third study aimed to address whether compliance, and in turn selection bias would systematically differ between groups of a trial of a physical activity intervention, and whether this would alter the results of the intervention itself. Results showed that compliance varied across trial condition, that selection bias with groups was different for each condition and that non-compliance hindered the exploration of the mediating effect of physical activity on psychological well-being. Study four involved the validation and calibration of a new wrist worn, waterproof physical activity monitor more compatible with 24 hour wear, thus potentially overcoming the compliance problems noted in the earlier studies. Results showed good concurrent and criterion validity, with high classification accuracy for the cut-points created. The final study assessed the acceptability and compliance with 24 hour wear in children and allowed a detailed examination of the underestimation of time spent in PA intensities that occurs from capturing shorter and different periods of the day. Results showed large misclassification with 10 hour capture periods relative to complete observation, with time in activity intensities varying across different periods of the day. The results of this thesis demonstrate that substantial selection bias and misclassification of time in activity intensities can be introduced through the decisions made during the processing of raw accelerometry data. Furthermore, this error alters the relationships between physical activity and psychological well-being. The results indicate that the true relationship between physical activity and psychological well-being in children may still be unknown, with researchers reporting relationships and effects only relevant to the measurement methods and data reduction processes they have employed. A method of overcoming selection bias and reducing misclassification is through 24 hour wear, which through the design of new accelerometers is now possible. Future studies should use monitors compatible with and acceptable for complete observation. This would result in more precise estimates of time spent in physical activity intensities and less selection bias. Both of these improvements would greatly increase our understanding of the relationship between physical activity and psychological well-being in children.

Walking is an essential task important to recovery after stroke. However, there is a limited understanding regarding the characteristics of walking in in-patients with stroke. The objectives of this thesis were to: 1) develop an instrument capable of acquiring temporal characteristics of everyday walking; 2) investigate the quantity and control of everyday walking; and 3) profile the task-specific link between walking and cardiorespiratory response. In study 1 we developed and validated a wireless monitoring system (ABLE system). Study 2 revealed low quantities of everyday walking (4816 steps; SD 3247) characterized by short bout durations (59.8s; SD 23.4) and asymmetric walking. In study 3 we observed a modest task-related response in HR(19.4% HRR); however, the intensity and duration of everyday walking did not approach the guidelines for aerobic benefit. Monitoring in-patient walking can help guide clinical decision making in developing methods to maximize recovery after stroke.

Walking is an essential task important to recovery after stroke. However, there is a limited understanding regarding the characteristics of walking in in-patients with stroke. The objectives of this thesis were to: 1) develop an instrument capable of acquiring temporal characteristics of everyday walking; 2) investigate the quantity and control of everyday walking; and 3) profile the task-specific link between walking and cardiorespiratory response. In study 1 we developed and validated a wireless monitoring system (ABLE system). Study 2 revealed low quantities of everyday walking (4816 steps; SD 3247) characterized by short bout durations (59.8s; SD 23.4) and asymmetric walking. In study 3 we observed a modest task-related response in HR(19.4% HRR); however, the intensity and duration of everyday walking did not approach the guidelines for aerobic benefit. Monitoring in-patient walking can help guide clinical decision making in developing methods to maximize recovery after stroke.

Submitted by Lilian Utraga dos Santos null (lilianutraga@hotmail.com) on 2018-01-18T19:40:00Z No. of bitstreams: 1 Dissertação de Mestrado enviar 18 jan 18.pdf: 1158643 bytes, checksum: 2b9d0ef4e468d0806d38ac2d5213a3e5 (MD5) / Approved for entry into archive by Isabel Pereira de Matos null (isabel@fmva.unesp.br) on 2018-01-18T20:02:45Z (GMT) No. of bitstreams: 1 santos_lu_me_araca_int.pdf: 1158643 bytes, checksum: 2b9d0ef4e468d0806d38ac2d5213a3e5 (MD5) / Made available in DSpace on 2018-01-18T20:02:45Z (GMT). No. of bitstreams: 1 santos_lu_me_araca_int.pdf: 1158643 bytes, checksum: 2b9d0ef4e468d0806d38ac2d5213a3e5 (MD5) Previous issue date: 2018-01-15 / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Nosso estudo avaliou as características biomecânicas (comprimento e frequência da passada, deslocamento dorsoventral, potência dorsoventral, propulsão, potência médio lateral e potência total) de potros da raça Mangalarga Marchador, comparando com os melhores animais adultos da propriedade com o objetivo de identificar precocemente características desejáveis da marcha. Foram avaliados doze potros nos primeiros quinze dias de vida e dez adultos, em uma mesma propriedade. A obtenção das variáveis cinemáticas e cinéticas foi realizada com o equipamento de análise de andamento Equimetrix (Centaure Métrix, Fontainebleau, France) e a velocidade acompanhada com uso de GPS preso no braço do treinador. Foi realizada a comparação dos dois grupos, ao passo e à marcha. Nossos resultados demonstraram que ao passo podem ser observadas precocemente nesta raça a frequência e a simetria desde o nascimento e a regularidade a partir do décimo primeiro dia de vida. Em relação à marcha, a regularidade foi o único parâmetro consistente desde o nascimento / The aim of this study was to compare the biomechanical characteristics of gait (length and frequency of the gait, dorsoventral displacement, dorsoventral power, propulsion, lateral power mean and total power) of foals and adult animals from Mangalarga Marchador breed to identify early characteristics of gait. Twelve foals were evaluated during the first 15 days of life and the results were compared to the mean values recorded from 10 adult horses. Kinematic and kinetic variables were obtained with Equimetrix (Centaure Métrix, Fontainebleau, France), and speed was monitored using a GPS attached to the trainer's arm. Step and marcha gait analyses were compared between groups. At walk, our results demonstrated that frequency and symmetry are similar to adults and can be observed early in foals since the day of birth whereas regularity is characteristic for this breed from the 11th day of life on. Regarding gait, regularity was the only consistent parameter since birth / FAPESP: 14/18232-8