Background: Obesity is a chronic disease characterized by a body mass index (BM1) of ≥ 30 kg/m2 which negatively impacts the musculoskeletal system and has been found to be a major contributing factor to obesity-induced biomechanical alterations during activities of daily living (ADLs). A certain level of mobility is required for all populations to maintain independence and a good quality of life becomes more difficult with excess weight. Using a reduced weight-bearing activity, such as the Alter Gravity treadmill, would be beneficial in an obese population to reduce the load on the joints and potentially decrease the risk of weight bearing injury while maintaining normal gait mechanics. The purpose of this dissertation was to determine the biomechanical effects of excess weight and weight distribution on ADLs. To address this, two different weight gain models were created to simulate central (CL) and peripheral (PL) weight gain compared to an obese group (OW), and normal weight group (UL) during different activities of daily living (ADLs). The purpose of the third study was to compare lower extremity joint kinematics and muscle activation patterns between obese and normal individuals at different levels of body support (100, 75, and 50%) while walking in the AlterG treadmill. Methods: 14 normal weight (BMI: 22.4 ± 1.8 kg/m2, age: 23.4 ± 3.6 yrs) and 17 obese (BMI: 33.2 ± 2.3 kg/m2, age: 31.6 ± 8.0 years) adults participated in different ADLs (gait and descending a set of stairs). Normal weight participants were loaded with two different external loads sufficient to increase their BMI by 5 kg/m2 (~22.6% body mass). Kinematic and kinetic data were collected with 3D motion analysis. Frontal plane hip and knee angles and moments were calculated. Results: During gait, the obese group walked at a significantly slower velocity compared to UL. Step length was 8.7% longer in UL and 7.4% longer in the CL compared to the OW. PL more closely mirrored the OW group in step length, flexion moment and extension moment and the CL more closely mirrored the obese group in sagittal plane knee and hip excursion, and peak hip flexion moment and extension moment during gait During the transition from descending stair walking to level gait, it was found that the PL, but not CL, decreased step length, increased step width, and increased proportion of the gait cycle spent in stance. During the transition from walking down the stairs to level gait it was found that CL and PL affect temporal spatial variables differently. PL also reduced peak hip adduction angle, increased peak hip flexion moment, decreased peak hip extension, decreased sagittal plane hip excursion, and decreased frontal plane hip excursion. Conversely, CL reduced peak hip flexion moment and trended to reduce peak hip extension moment. To determine the effects of reduced body mass per se on improved biomechanics, we needed a model that would prevent associated changes in segmental volume. Therefore, using an AlterG treadmill facilitated this method. At 100 % BW support, mean ST and VM EMG activity were significantly higher in the obese compared to the normal weight groups. There were also differences found at 75 % BW support in ST in the obese being greater than the normal. Conclusions: Combined, the overall results of this dissertation suggest that weight gain is able to be modeled but is variable and task specific. The CL has proven to be the weight gain model that which elicits a better biomechanical obese response when normal weight individuals are loaded. Further work is needed to understand how to truly mimic obesity with an external load.

This project is the biography of a symbol: that of the holy woman motif in William Butler Yeats’s oeuvre. For most of Yeats’s writing life, beautiful women have a place of spurious privilege in his spiritual imagination because they have an intrinsic connection with the divine otherworld. In chapters on Yeats’s beauty-worship in his long fin de siecle, Olivia Shakespear’s critique of that beauty-worship in her fiction, and the role of A Vision in The Winding Stair and Other Poems, I argue that Yeats revised the holy woman motif from a limited and limiting goddess or helpmeet role in his youthful work to a full-fledged religious meaning-maker--a Creatrix--in the last decade of his career. I include a study of Olivia Shakespear’s fiction in this project because each of her seven fictional works critiques what she saw as the male tendency from which Yeats’s symbology sprang: the tendency to feign worship of a beautiful woman while simultaneously limiting her ability to be a Creatrix. However, the transformation that Yeats’s system underwent between the 1925 and 1937 versions of A Vision enabled the poet to create a model of religious identity that does not require the erasure of the self and its human desires and therefore makes space in his pantheon for the Creatrix.

This thesis presents a prototype of Unmanned Cooperative Fire-Seeking and -Fighting Robots (UCSFRs) which have a new way to climb up the stairs or traverse over obstacles with a ball screw. There are three unmanned vehicles (one Mother Vehicle (MV) and two Daughter Vehicles (DVs)) presented in this research. The MV can carry two DVs to climb stairs. They can communicate with each other using Bluetooth communication modules. The core system of the UCSFRs is a PIC 16F877 microcontroller on a 2840 development board. The software is written in C language and the interface is established through Hyper Terminal built in Windows XP. UCSFRs are low cost unmanned vehicles compared with other commercial ones. The double-deck structure is applied on the DVs. The body of the MV can be extended for special purposes. In this research, there are three tests used to verify the functionality of the UCSFRs: (1) MV?s finding and stopping fire, (2) Communication between the MV and the DVs, and (3) the MV?s climbing stairs. In the second test, the DVs run in the opposite direction to assist MV detect fire. By cooperative work, they can save time finding the fire. The MV will go to the hightemperature area according to the data sent by the DVs. Because of the features mentioned above, UCSFRs can be used to perform dangerous tasks instead of fire-fighters.

A flapper valve is made from a hardened and tempered high strength strip steel which opens and shuts as it is subjected to very high cyclic loads. Steel strip of which flapper valves are made from can   encounter a surface defect which are anticipated to influence fatigue life negatively. In this study, the influence of surface scratches on fatigue life of flapper valve strip was investigated. The analysis was carried out by using thirty samples that were blanked out of eight different steel strips in the transverse direction. Of these samples, fifteen of them had scratches on the surface and fifteen did not, all these samples were fatigue tested by constant amplitude method. An S-N curve was plotted based upon the values and results from the fatigue test, considering the curve as the nerve center in relation with fractrographic studies using the Scanning electron microscope. Therefore this master thesis work aims to explain the influence of scratches on fatigue life of flapper valve strip and suggest future improvements based on the findings.

This thesis examines the sources and method used by Sir James Dalrymple, 1st Viscount Stair, when writing and revising his seminal work, the Institutions of the Law of Scotland (1681). In doing so, it focuses particularly on Stair’s titles on the law of obligations. The thesis shows how Stair used learned authority and continental legal treatises. It demonstrates that Stair relied particularly upon Hugo Grotius’ De jure belli ac pacis (1625), Petrus Gudelinus’ De jure novissimo (1620), and Arnoldus Vinnius’ Commentarius academicus et forensis (1642), and, to a lesser extent, Vinnius’ Jurisprudentia contracta (1624-1631) and Arnoldus Corvinus’ Digesta per aphorismos (1642). It establishes when, in the process of writing and later revising the Institutions, Stair first used and when he returned to these continental legal treatises. It explains Stair’s pattern of borrowing from these treatises, and shows how his method and pattern of borrowing changed as he revised the Institutions. It establishes Stair’s purpose in consulting each of these works and how he was influenced by them. Overall, the thesis explains Stair’s method of writing and his use of sources and authorities, places his work in the context of continental jurisprudence, and thus significantly enhances current understanding of Stair’s Institutions.

Subir e descer escadas são atividades funcionais habituais e muito relatadas como queixa principal por pacientes com alterações ortopédicas como a síndrome dolorosa femoropatelar - por ser um movimento que acarreta descarga de peso unilateral e assim causa um aumento da dor - e por pacientes com afecções neurológicas - devido à dificuldade na execução deste gesto. Além disso, a subida e descida de escadas é habitualmente utilizada como técnica terapêutica na reabilitação destes pacientes; porém poucos estudos foram realizados com o intuito de caracterizar este gesto e, estes estudos, concluem que a alta variabilidade dos dados não permite confirmar os resultados. Estudos com pacientes com dor femoropatelar usualmente avaliam estes sujeitos com eletromiografia de superfície e sugerem que exista um déficit de equilíbrio na musculatura estabilizadora da patela e que esta é a causa da dor nestes pacientes; porém, também há uma grande variabilidade nos resultados encontrados, não sendo possível confirmar esta hipótese. Neste contexto, este estudo teve o objetivo de verificar quais parâmetros do sinal eletromiográfico apresentaram boa reprodutibilidade e menor variabilidade e são, portanto, mais adequados para caracterizar o gesto proposto, podendo ser utilizado para comparar grupos de indivíduos com e sem dor femoropatelar. Para isto, foi utilizada a eletromiografia para avaliar a atividade dos músculos vasto lateral e vasto medial do quadríceps durante a subida de escada em 39 indivíduos clinicamente saudáveis e 23 indivíduos com dor femoropatelar. Os resultados mostraram que os parâmetros que apresentaram boa reprodutibilidade entre os dois dias de avaliação foram: início de ativação, duração da contração muscular, tempo mediano da contração, intensidade do sinal, co-ativação muscular e frequência mediana. Dentre estes parâmetros, aqueles que permitiram diferenciar os grupos de estudo foram o tempo mediano da ativação, que ocorreu mais tardiamente nos indivíduos com dor e a co-ativação muscular, que demonstrou menor porcentagem de ativação conjunta nos indivíduos com dor. Estes dados indicam uma alteração no controle neuromotor durante a subida de escada, sugerindo que a abordagem clínica deva passar por treinos de equilíbrio, coordenação e propriocepção, para melhorar a estabilidade articular durante a realização de atividades dinâmicas. / Go up and down stairs are functional activities very habitual and reported as complaint for patients with orthopedic alterations as patellofemoral pain syndrome because it is a movement that carries unilateral weight bearing and thus cause an increase in pain and for patients with neurological disorders due to the difficulty in carrying out this gesture. Moreover, the ascent and descent of stairs is usually used as a therapeutic technique in the rehabilitation of these patients, but few studies have been conducted in order to characterize this gesture and, these studies conclude that the high variability of the data does not confirm the results. Studies on patients with patellofemoral pain usually assess these subjects with surface electromyography and suggest that there is a balance deficit in the patella stabilizer muscles and that this is the cause of pain in these patients, but there is also a great variability in the results, that does not allow to confirm this hypothesis. In this context, this study aimed to determine which parameters of electromyographic signals showed good reproducibility and low variability and are, therefore, more appropriate to characterize the proposed gesture and can be used to compare groups of individuals with and without patellofemoral pain. For this, we used electromyography to evaluate the activity of the vastus lateralis and vastus medialis of the quadriceps during stair climbing in 39 clinically healthy individuals and 23 individuals with patellofemoral pain. The results showed that the parameters with good reproducibility between the two days of evaluation were: onset, duration of muscle contraction, median time of contraction, intensity of activation, muscular co-activation and median frequency. Among these parameters, those that could differentiate the groups were the median time of activation, which occurred later in subjects with pain and muscle co-activation, which showed a lower percentage of combined activation in individuals with joint pain. These data indicate a change in neuromotor control during stair climbing, suggesting that the clinical approach should undergo training of balance, coordination and proprioception, in order to improve joint stability while performing dynamic activities.

It is often the case that emergency first responders are well equipped and trained to deal with a situation that involves evacuation of someone with a physical disability. However, emergency responders are not always the first line of defense, or they may be otherwise occupied with assisting others. This research examined the effects of instructions for emergency stair travel devices on untrained or novice users. It was hypothesized that through redesign of the evacuation instructions, untrained individuals would be able to successfully prepare an evacuation chair and secure someone with a disability more effectively and efficiently. A prepost study design was used with an instructional redesign occurring as the manipulation between phases. There was an improved subjective understanding and improved performance metrics, such as reduced time on task and a reduction of the number of instructional glances, across three evacuation chairs when using the redesigned instruction sets. The study demonstrated that visual instruction style can account for a significant portion of explained variance in the operation of emergency stair travel devices. It also showed that improvements in instruction style can reduce time on task across device type and age group. The study failed to demonstrate that there was a performance decrement for older adults in comparison to younger adults because of the cognitive slowing of older adult information processing abilities. Results from this study can be used to support future iterations of the Emergency Stair Travel Device Standard (RESNA ED-1) to ensure that instructional design is standardized and optimized for the best performance possible.

Impairment of stereoacuity is common in the elderly population and is found to be a risk factor for falls. The purpose of these experiments was to extend knowledge regarding impairment of binocular vision and adaptive gait. Firstly using a 3D motion analysis system to measure how impairment of stereopsis affected adaptive gait during a negotiation of a step, secondly by determining which clinical stereotest was the most reliable for measuring stereoacuity in elderly subjects and finally investigating how manipulating the perceived height of a step in both binocular and monocular conditions affected negotiation of a step. In conditions of impaired stereopsis induced by acutely presented monocular blur, both young and elderly subjects adopted a safety strategy of increasing toe clearance of the step edge, even at low levels of monocular blur (+0.50DS) and the effect was greater when the dominant eye was blurred. The same adaptation was not found for individuals with chronic monocular blur, where vertical toe clearance did not change but variability of toe clearance increased compared to full binocular correction. Findings indicate stereopsis is important for accurately judging the height of a step, and offers support to epidemiological findings that impaired stereoacuity is a risk for falls. Poor agreement was found between clinical stereotests. The Frisby test was found to have the best repeatability. Finally, a visual illusion that caused a step to be perceived as taller led to increased toe elevation. This demonstrates a potential way of increasing toe clearance when stepping up and hence increase safety on stairs. / The Study data files are unavailable online.

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