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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
161

Lombalgies, âge et expositions professionnelles / Low back pain, age and occupational exposure

Plouvier, Sandrine 11 May 2011 (has links)
Les effets à court ou moyen terme de certaines expositions professionnelles biomécaniques sur lerisque de lombalgie sont reconnus. Les effets à long terme sont moins connus. Ces expositionscontribuent aux inégalités sociales de lombalgies,mais ceci est peu documenté une fois la carrièreterminée.Dans un contexte de débat sur l’âge de la retraite et la prise en compte de la pénibilité au travail,l'objectif de cette thèse était d'apporter des éléments de connaissances sur les liens entreexposition aux risques professionnels physiques et lombalgies autour de l’âge de la retraite, ainsique sur la présence d'inégalités sociale de lombalgies parmi des actifs vieillissants et des retraitéset la contribution de ces expositions à ces inégalités.Les lombalgies ayant duré plus de 30 jours au cours des 12 mois précédents ont été étudiéesdans la cohorte Gazel et l'Enquête Décennale Santé 2002 (EDS).Des arguments en faveur de la persistance des effets d'expositions physiques professionnelles audelà de la période d'activité ont été trouvés. Les données de l’EDS suggèrent que ces effetss’estomperaient au-delà d’un certain âge.Les expositions professionnelles, en particulier biomécaniques, jouent un rôle majeur dans lesinégalités sociales de lombalgies chez les hommes de la cohorte Gazel, actifs vieillissants etjeunes retraités. Par contre, de telles inégalités ne sont pas observées chez les retraités de 60 à74 ans de l'EDS.Ce travail montre l'importance en matière de lombalgies persistantes/récidivantes d'expositionsprofessionnelles a priori accessibles à une démarche de prévention, et l'intérêt de considérer leparcours professionnel dans les politiques de retraite / Some biomechanical exposures at work are recognized short term risk factors for low back pain(LBP). However, long term effects, are not well known. In addition, occupational exposures seemto contribute to social inequalities in low back pain, but this contribution is less documented forolder subjects.In many developed countries, governments are now reconsidering retirement policies. In thiscontext, the objective of this work was firstly to provide additional knowledge about the linksbetween physical exposure and LBP among aging workers and retirees, and secondly to assesssocial inequalities in LBP in this age group and the contribution of occupational factors to suchinequalities.Two populations were studied : volunteers from the Gazel cohort and participants to a Frenchnational survey on health (EDS 2002). The same definition for LBP could be used in bothpopulations : LBP which lasted more than 30 days in the previous 12 months.LBP was associated with physical occupational exposures among aging workers and youngretirees in both populations. Results were consistent with the hypothesis of a persistence of effectsonce occupational exposure has ceased, except among the oldest retirees in the EDS 2002.Biomechanical exposures played a major role in social inequalities for LBP among aging workersand young retirees in the GAZEL cohort. Such inequalities were not observed among the retireesaged 60 to 74 years (men and women) from the EDS 2002.The results highlight the importance of past occupational exposures at retirement age.
162

Occupational Exposures as Social Determinants of Aging / Expositions de Travail : Déterminants Sociaux de la Vieillissement

Sabbath, Erika 16 April 2012 (has links)
Cette thèse s’intéresse à la contribution des expositions professionnelles —chimiques, biomécaniques, et psychosociaux—tout au long de la vie dans les inégalités sociales de santé liés au vieillissement. Les trois papiers de la thèse essaient de combler les lacunes dans les connaissances sur les effets à long terme des expositions professionnelles et la contribution des expositions individuelles et conjointes dans ces inégalités. Le premier papier cherche à savoir si le niveau d’éducation atteint dans l’enfance modifie l’effet de l’exposition professionnelle aux solvants au cours de la carrière sur la fonction cognitive après 55 ans.. Nous avons trouvé que l’effet de l’exposition aux solvants sur la fonction cognitive était différent selon le niveau d’éducation.. Le deuxième papier discute les effets combinés des expositions biomécaniques et psychosociaux au cours de la vie professionnelle sur la santé physique et fonctionnelle après la retraite. Nous avons trouvé qu’une forte exposition à la fois aux risques physiques et psychosociaux au cours de la vie active est associée à une capacité fonctionnelle bien plus faible après la retraite que l’exposition à un seul type de risques. Aussi, l’effet était différent chez les hommes et chez les femmes. Le troisième papier est un papier méthodologique qui discute des alternatives aux formes longues des échelles généralement utilisées pour évaluer les expositions biomécaniques au travail. Nous avons cherché à vérifier si la question « Trouvez-vous votre travail fatiguant physiquement?» pourrait être une mesure de substitution acceptable pour évaluer des expositions détaillées.. Nous avons comparé la mesure à un item à une mesure plus complète de 38 expositions spécifiques dans huit domaines. Nous avons trouvé que la mesure à un item était plus valide chez les participants fortement exposés à des contraintes biomécaniques de travail. En somme, cette thèse a montré que les expositions professionnelles peuvent à la fois exacerber les disparités existantes en matière de santé et les perpétuer au delà de la retraite. / This dissertation focuses on how occupational exposures throughout the lifecourse—chemical, physical, and psychosocial—contribute to social patterns in aging outcomes, addressing the gap in knowledge about lasting effects of occupational exposures and the contribution of individual and combined exposures to social patterns in aging. The first paper explores whether childhood educational attainment modifies effects of occupational solvent exposure during the career on cognitive function after age 55. We found differential effects of solvent exposure on cognition by educational attainment. The second paper looks at combined physical and psychosocial exposures during working life and effects on physical health and functioning after retirement. This paper finds that high exposure to both physical and psychosocial hazards at work is associated with worse functional capacity in retirement than exposure to either one separately; the pattern of this relationship differs for men and women. The third paper is a methodology paper exploring alternatives to extensive testing batteries often used to evaluate physical workplace exposures. We tested whether the question “Do you find your work physically strenuous?” was an acceptable proxy measure for more detailed exposure assessments by comparing the measure to a comprehensive self-report measure of 38 specific biomechanical strains across eight domains. We found that the measure was most valid in the populations that were most highly exposed to physical strains at work. In general, this dissertation found that occupational exposures can exacerbate existing disparities in health and perpetuate disparities into and beyond retirement.
163

Estudo da correlação instrumental e sensorial de uma composição aromática aplicada na pele em função do ciclo menstrual / Study of instrumental and sensory correlation of a aromatic composition on the skin in function of mentrual cycle.

Costa, Claudia Silva Cortez Pereira da 19 December 2013 (has links)
A área de perfumaria no mundo vem se desenvolvendo a cada dia buscando maior conhecimento das matérias-primas aromáticas, desde suas reações, estabilidade até suas interações com o substrato onde é aplicado, sempre em busca do conhecimento de todas as variáveis que possam influenciar a relação perfume-substrato e a aceitação dos consumidores, medida por meio da avaliação sensorial. Apesar de muitos estudos sobre a relação perfume-pele, poucos envolveram a relação com ciclo menstrual. Neste estudo o objetivo foi correlacionar às análises sensorial e instrumental (medidas biomecânicas e cromatográficas), estudar as matérias-primas aromáticas em função do ciclo menstrual. O estudo envolveu indivíduos com idade entre 18-40 anos: 29 mulheres e 3 homens, estes usados como grupo controle. Cada voluntária teve 40 &#181;l da composição aromática Ciclo 1910 aplicado no antebraço, onde foram feitas as medidas biomecânicas (corneometria, sebumetria e TEWL) nos tempos inicial e 6h. Nos tempos inicial, 1.5h, 3h, 4,5h e 6h se auto-avaliaram sensorialmente a intensidade de perfume por meio de escala sensorial de magnitude rotulada (LMS) e foram coletados os compostos aromáticos liberados pela técnica de headspace e analisados por espectrometria com cromatografia a gás e detetor de massa (CGMS). Realizou-se também medidas biomecânicas de corneometria, sebumetria e TEWL interescapulares em 5 voluntárias nos tempos inicial e 6h para comparação. Os resultados obtidos foram que as fases do ciclo não interferiram nas variáveis biomecânicas (p>0,05) quando analisadas isoladamente. Para as medidas realizadas no antebraço, os índices de Corneometria (p<0,001) e TEWL (p: 0,011) na região tratada apresentou média maior que a do controle. A média dos índices de Corneometria e Sebumetria da região do antebraço tratada foi menor (p<0,001) que da região interescapular. Na análise cromatográfica não houve um padrão de resposta em diferentes fases do ciclo. As correlações entre a avaliação sensorial e instrumental (cromatografia e propriedades biomecânicas) não observaram nenhum nível de correlação (p>0,05). A Cromatografia (dados cromatográficos) foi maior na fase Folicular que nas fases Menstrual e Ovulatória (p=0,003), ao considerar como variável resposta em função do ciclo menstrual e da avaliação sensorial. Houve uma forte correlação positiva entre a análise sensorial e a avaliação na pele do homem (p<0,001). No entanto, o fator intrínseco do indivíduo Mulher influenciou na resposta, ocasionando grande variabilidade, porém percebeu-se claramente que os hormônios sexuais interferiram na resposta sensorial, cromatográfica e biomecânica da pele. / The perfumery in the world has been developed everyday bringing more knowledge about aromatic raw-materials, as from chemistry reactions, stability until their interactions with substrate where is applied, always looking for variables could influence in the relation perfume-substrate and consumer acceptability, measured by sensory evaluation. Despite a lot of studies were done on this subject, few involved effects as function of menstrual cycle. The aim of this study was to correlate sensory and instrumental analysis (biomechanical and chromatographic measurements), to study the olfactory profile of raw materials in function of menstrual cycle. The study involved people with 18-40 years old: 29 volunteers, three men, who were used as control group. Each volunteer had 40 &#181;l of perfume applied on forearm, where were done Biomechanical measurements (Corneometer, Sebumeter and TEWL) at initial and 6h, At time initial, 1.5h, 3h, 4.5h and 6h; they did self-sensory assessment in perfume intensity in own forearm using labeled magnitude scale (LMS) and also where aromatic compounds released were collected by headspace technique spectrometry and gas chromatography with mass detector (CGMS). In addition, it was done biomechanical measurements (Corneometer, Sebumeter and TEWL) on interscapular region at initial and 6h for comparing. Resulting that the phases of the cycle did not affect the biomechanical variables (p > 0.05) when analyzed individually. For measurements in the forearm, Corneometry index (p < 0.001) and TEWL (p=0.011) in the treated area were higher than the control. The average of the Sebumetry, Corneometry indexes of the forearm treated was lower (p <0.001) than the interscapular region. In the analysis of chromatographic, there was a standard response at different stages of the menstrual cycle, however the analysis by individual had no a pattern response to the release of aromatic compounds. The correlations between sensory and instrumental (chromatography and biomechanical properties) did not observe any correlation (p> 0.05). But when considering chromatography as the response variable as a function of the menstrual cycle and the sensory evaluation, the follicular phase was higher than the Menstrual and Ovulatory phase (p=0.003). There was a strong positive correlation between sensory analysis and evaluation on men skin (p<0.001). However, the intrinsic factor of the individual woman influenced the response, leading to large response variability; however, see clearly that sex hormones interfere in the sensory response, chromatographic and biomechanics of the skin.
164

In-vivo Tracing of Vagal Projections in the Brain with Manganese Enhanced Magnetic Resonance Imaging

Steven T. Oleson (5930780) 17 January 2019 (has links)
<p>Current challenges in neuronal tract tracing include sacrificing the animal, detailed sectioning of the brain, and cumbersome reconstruction of slices to gather information, which are very tedious, time consuming, and have low-throughput. In this regard, Manganese-enhanced Magnetic Resonance Imaging (MEMRI) has been an emerging methodology for fiber tract tracing <i>in vivo</i>. <i></i>The manganese ion (Mn<sup>2+</sup>) is paramagnetic and is analogous to calcium ions (Ca<sup>2+</sup>), which allows it to enter excitable cells through voltage-gated calcium channels, thereby reporting cellular activity in T<sub>1</sub>-weighted MR images<i>. </i>Moreover, once the Mn<sup>2+</sup>enters the cell, it will move along the axon by microtubules, release at the synapse, and then uptake by post-synaptic neurons, hence revealing the pathway of Mn<sup>2+ </sup>transportation. While most MEMRI neuronal tracing studies have focused on mapping circuitries within the brain, MEMRI has rarely been applied to trace peripheral nerve projections into the brain. </p><p>In this thesis, I will propose the use of MEMRI to trace vagal nerve projections into the central nervous system by showing enhancement of neuronal pathways with an optimized protocol. This protocol demonstrates <i>in vivo </i>monitoring of manganese transport into the brain from the nodose ganglion and shows how the enhancement in MR images can be promoted with vagus nerve stimulation (VNS). Additionally, I will present preliminary findings, for the very first time, that show the downstream projection of the sympathetic pathway from the brainstem. In sum, the technique presented in this thesis will shed light on the use of MEMRI to study the functional results of using clinically-based VNS settings</p>
165

The Mechanotransduction of Hydrostatic Pressure by Mesenchymal Stem Cells

Seyedeh Ghazaleh Hosseini (5931062) 17 January 2019 (has links)
<div>Mesenchymal stem cells (MSCs) are responsive to mechanical stimuli that play an essential role in directing their differentiation to the chondrogenic lineage. A better</div><div>understanding of the mechanisms that allow MSCs to respond to mechanical stimuli is important to improving cartilage tissue engineering and regenerative medicine. Hydrostatic pressure (HP) in particular is known to be a primary mechanical force in joints. However, little is known about the underlying mechanisms that facilitate HP</div><div>mechanotransduction. Understanding the signaling pathways in MSCs in transducing HP to a beneficial biologic response and their interrelationship were the focus of this thesis. Studies used porcine marrow-derived MSCs seeded in agarose gel. Calcium ion Ca++ signaling, focal adhesion kinase (FAK) involvement, and sirtuin1 activity were investigated in conjunction with HP application.</div><div><br></div><div><div>Intracellular Ca++ concentration was previously shown to be changed with HP application. In our study a bioreactor was used to apply a single application of HP to the MSC-seeded gel structures and observe Ca++ signaling via live imaging of a fluorescent calcium indicator in cells. However, no fluctuations in Ca++ concentrations were observed with 10 minutes loading of HP. Additionally a problem with the biore actor design was discovered. First the gel was floating around in the bioreactor even without loading. After stabilizing the gel and stopping it from floating, there were still about 16 µm of movement and deformation in the system. The movement and deformation was analyzed for the gel structure and different parts of the bioreactor. </div><div><br></div><div>Furthermore, we investigated the role of FAK in early and late chondrogenesis and also its involvement in HP mechanotransduction. A FAK inhibitor was used on MSCs from day 1 to 21 and showed a dose-dependent suppression of chondrogenesis. However, when low doses of FAK inhibitor added to the MSC culture from day 21 to 42, chondrogenesis was not inhibited. With 4 hour cyclic HP, FAK phosphorylation increased. The beneficial effect of HP was suppressed with overnight addition of the</div></div><div><div>FAK inhibitor to MSC medium, suggesting FAK involvement in HP mechanotransducation by MSCs.</div></div><div><br></div><div>Moreover, sirtuin1 participation in MSC chondrogenesis and mechanotransduction was also explored. The results indicated that overnight sirtuin1 inhibition increased chondrogenic gene expression (Agc, Col2, and Sox9) in MSCs. Additionally, the activity of sirtuin1 was decreased with both 4 hour cyclic hydrostatic pressure and inhibitor application. These two together demonstrated that sirtuin1 inhibition enhances chondrogenesis.</div><div><br></div><div><div>In this research we have investigated the role of Ca++ signaling, FAK involvement, and sirtuin1 activity in the mechanotransduction of HP in MSCs. These understandings about the mechanisms regulating the chondrogenesis with respect to HP could have important implications for cartilage tissue engineering and regenerative studies.</div></div>
166

Comportamento biomecânico de diferentes protocolos cirúrgicos/protéticos para maxila atrófica: análise fotoelástica e extensométrica /

Campaner, Marcio. January 2019 (has links)
Orientador: Aldiéris Alves Pesqueira / Coorientador: Marcelo Coelho Goiato / Banca: Aimée Maria Guiotti / Banca: Ricardo Shibayama / Resumo: Os pacientes com maxila atrófica ainda representam um problema complexo para os cirurgiões dentistas, tornando sua reabilitação um grande desafio, devido à baixa quantidade e qualidade óssea, e também de áreas anatômicas a serem preservadas como a fossa nasal e o seio maxilar que pode apresentar-se pneumatizados. O objetivo deste estudo foi avaliar a distribuição de tensões qualitativa e quantitativamente, por meio da análise fotoelástica (AF) e extensométrica (AE), de três diferentes protocolos alternativos ao procedimento de enxertia óssea para a reabilitação implantossuportada de maxila atrófica: implante convencional (S- standard - 3,75x11,5mm) associado a implante curto (C) (5x7mm), implante convencional (S) associado a implante inclinado em 30º e dois implantes convencionais instalados no eixo axial utilizando prótese com extensão em cantilever. A partir de um protótipo da maxila edêntula com atrofia na região posterior, confeccionada por meio de um modelo digital 3D, os corpos de prova foram divididos em 04 grupos de 01 espécime cada para AF e quatro grupos de 05 espécimes para a AE. Foram confeccionados 24 modelos, destes 4 foram de resina fotoelástica (PL-2) e 20 de poliuretano (F160). Foram utilizados implantes do tipo cone morse e confeccionadas próteses fixas implantossuportadas múltiplas (14-16) parafusadas. Os grupos foram divididos de acordo com protocolo de reabilitação proposto em: ISA - dois implantes (S) paralelos ao eixo axial, sendo um instalado na região... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Patients with atrophic maxillary still represent a challenge to rehabilitate for dentists in general due to limitations on bone quantity and quality and the anatomical setting of the sites to be preserved, such as nasal cavity and maxillary sinus, that could be pneumatized. The aim of this study was to assess qualitative and quantitative the stress distribution, through photoelastic analysis (PA) and strain gauge (SG), of three alternative techniques to bone augmentation procedures for implant placement: standard implant (S-standard -3,75x11,5mm) associated to short implant (C) (5x7mm), standard implant (S) associated to 30ºtilted implant, two conventional implants placed in the long axis and a cantilever prosthesis. A maxillary prototype model, with posterior atrophic region, was manufactured from a digital 3D model and divided into four groups with 01 specimen for the PA and 05 specimen for the SG. A total of 24 models were manufactured, 4 from photoelastic resin (PL-2) and 20 from polyurethane (F160). Morse taper implants were used and multiple screwed implant supported prostheses were manufactured (14-16). The groups were divided according to the rehabilitation protocol: ISA -two parallel implants in the long axis (S), one in the pre-molar region (14) and in the molar region (16); ISAICA-two parallel implants in the long axis, one standard (S) in the pre-molar region (14) and one short (C) in the molar region (16); ISAISI -two standard implants, one parallel to the long axis (14) and one tilted at 30 ̊ (16) and ISAPC -two parallelimplants in the long axis, in the first (14) and second (15) pre molar region, with a cantilever prostheses (16). For the PA, the assemble photoelastic model/implants/prostheses was positioned in a circular Abstract20polariscope associated to a universal test machine (EMIC), and an axial load of 100N applied (Complete abstract electronic access below) / Mestre
167

Biomechanical analysis on the lower extremities during Tai Chi exercise. / CUHK electronic theses & dissertations collection

January 2006 (has links)
Part 1. Characteristics of foot movement in Tai Chi exercise. The performance of 16 experienced Tai Chi practitioners demonstrating a whole set of 42-form Tai Chi movements were recorded with two cameras. The APAS motion analysis system was used to identify the foot supporting and stepping characteristics during the practice. Seven foot support patterns and six step directions were identified. The results revealed that compared with normal walking, Tai Chi movement had more double support and less single support total duration. The duration of each support pattern was longer and movement from one pattern to the next was slow. The duration of each step direction was short, and changes of direction were frequent. It was expected that support patterns changed slowly, and combined with various step directions, they were found to be better than those of walking in simulating the gait challenges that may be encountered in daily activities. / Part 2: The plantar pressure distribution during Tai Chi exercise. The purpose of this study is to describe and quantify the plantar pressure distribution characteristics during Tai Chi exercise and to explain the beneficial effects of Tai Chi on balance control and muscle strength as compared with normal walking. Sixteen experienced Tai Chi practitioners participated in this study. Five typical Tai Chi movements represented by stepping forward, backward, sideways, up-down, and fixing could be isolated from the whole set of 42-form Tai Chi. The pressure-time integral, ground reaction force, displacement of center of pressure during the performance of the five typical movements were recorded and analyzed by the Pedar-X insole system (Germany). Results showed that during Tai Chi movements, the loading of the first metatarsal head and the great toe were significantly greater than in other regions (p&lt;0.05). The ground reaction forces varied between the Tai Chi movements and normal walking. Compared with normal walking, the locations of the center of pressure in the Tai Chi movements were significantly more medial and posterior at initial contact (p&lt;0.05), and were significantly more medial and anterior at the end of contact with the ground (p&lt;0.05). The displacements of the center of pressure were significantly wider (p&lt;0.05) in the mediolateral direction in the forward, backward and sideways Tai Chi movements. The displacement was significantly larger (p&lt;0.05) in the anterposterior direction in the forward movement. The plantar pressure characteristics of Tai Chi movements found in this study may be one of the important factors for Tai Chi's improvement of balance control and muscle strength. / Part 3. The duration and plantar pressure distribution during one-leg stance in Tai Chi exercise. The aim of this study is to quantify the one-leg stance duration and plantar pressure distribution during the one-leg stance in Tai Chi and to try to elaborate on its probable effects on the ability to balance on one leg. Sixteen experienced Tai Chi practitioners participated in this study. The Novel Pedar-X insole system (Germany) was used to record the plantar forces during the execution of a set of 42-form Tai Chi movements and during normal walking. The one-leg stance duration and plantar pressure distribution during the one-leg stance were analyzed. Results showed that in Tai Chi, the total duration spent in the one-leg stance was less (p&lt;0.05), the duration of each one-leg stance was longer (p&lt;0.01) and the medial-lateral displacement of the center of pressure was greater (p&lt;0.05) than during normal walking. The peak pressure and pressure-time integral of the second and third metatarsal heads and the fourth and fifth metatarsal heads were significantly greater (p&lt;0.05) than those of other plantar regions during the one-leg stance in normal walking; whereas the peak pressure and pressure-time integral of the first metatarsal head and the great toe were significantly greater (p&lt;0.05) than those of other plantar regions during the one-leg stance in Tai Chi. The longer duration of each one-leg stance and the plantar pressure distribution characteristics during the one-leg stance in Tai Chi may be associated with an improved ability to balance on one leg. / Part 4. The muscle contraction characteristics of the lower extremities during Tai Chi exercise. The objective of this study is to examine the muscle contraction characteristics of the lower extremities during Tai Chi exercise and to explain the beneficial effect of Tai Chi on the improvement of muscle strength. Sixteen experienced Tai Chi practitioners participated in this study. Five typical Tai Chi movements, represented by stepping in forward, backward, sideways, up-down and fixing were selected. The electromyographic activity of the rectus femoris, semitendinosus, gastrocnemius, and anterior tibialis muscles were recorded by Delsys electromyography measurement system (USA) during the performance of five typical Tai Chi movements. (Abstract shortened by UMI.) / Mao Dewei. / "August 2006." / Adviser: Youlian Hong. / Source: Dissertation Abstracts International, Volume: 68-03, Section: B, page: 1598. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2006. / Includes bibliographical references (p. 102-112). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts in English and Chinese. / School code: 1307.
168

Realidade virtual e sensores inerciais no desenvolvimento da tecnologia assistiva : um sistema para estudo da marcha humana baseado em fusão de sensores inerciais

Corrêa, Daniel dos Santos January 2015 (has links)
A marcha humana, ou caminhada, é um padrão cíclico de movimentos corporais que se repetem a cada passo que desloca um indivíduo de um local a outro. Atualmente, avaliações biomecânicas da marcha humana tem sido utilizado no diagnóstico de alterações neuromusculares, músculo-esqueléticas e como forma de avaliação pré e pós-tratamento cirúrgico, medicamentoso e/ou fisioterapêutico. O presente trabalho apresenta o desenvolvimento de uma ferramenta acadêmica de baixo custo para o estudo da marcha humana. Esse sistema consiste no sensoriamento da marcha de um usuário através de sensores inerciais e de um modelo virtual do corpo humano para permitir a visualização do movimento gerado. Dessa maneira o usuário poderá ter suas ações corrigidas por sua percepção visual e também corrigida pelas orientações de um fisiatra ou fisioterapeuta que terá a reprodução do modelo virtual conforme a movimentação detalhada do paciente para análise. O sistema ainda efetuará os registros das variáveis cinemáticas da marcha (tais como aceleração, velocidade angular, angulações dos membros sensoriados) para estudos e acompanhamento mais detalhado da sua recuperação e/ou tratamento. Como resultado, o sistema desenvolvido obteve erros médios de X 0,52º Y 1,20º Z 1,80º e erros em RMS de X 3,01º Y 3,30º Z 5,70º quando comparados com um sistema comercial, sendo esse resultado próximo à literatura e aplicável em exames biomecânicos de marcha. / The human gait is a cyclical pattern of body movements that are repeated every step that moves a subject from one location to another. Currently, biomechanical assessments of human gait has been used for diagnosing neuromuscular disorders, musculoskeletal and as a way of pre and post-surgical treatment, medication and/or physical therapy. This paper presents the development of a low cost academic tool for the study of human gait. This system consists of sensing the motion of a user through inertial sensors and a virtual model of the human body to allow the visualization of the generated movement. In this way, the user can have its actions corrected by his visual perception and also corrected by therapist or physiotherapist who will visualize the virtual model as the detailed movements of patient. The system will also record the kinematic gait variables (as acceleration, angular velocity, angles of the sensed members) for studies and more detailed monitoring of their recovery and/or treatment. As result, the developed system obtained average errors of X 0,52º Y 1,20º Z 1,80º and errors in RMS X 3,01º Y 3,30º Z 5,70º compared to a commercial system, and these results close to the ones seen in literature and applicable in biomechanical tests of gait.
169

Comportamento biomecânico de diferentes protocolos cirúrgicos/protéticos para maxila atrófica: análise fotoelástica e extensométrica / Biomechanical behavior of diferente surgical protocols for atrofic maxillas: photoelastic and Strain Gauge analysis

Campaner, Marcio [UNESP] 18 January 2019 (has links)
Submitted by Marcio Campaner (marciocampaner17@gmail.com) on 2019-01-30T01:36:27Z No. of bitstreams: 1 Dissertacao FINAL.pdf: 1090929 bytes, checksum: e09668532be013be367eec9ff777fa8c (MD5) / Approved for entry into archive by Claudio Hideo Matsumoto null (claudio@foa.unesp.br) on 2019-01-30T13:03:21Z (GMT) No. of bitstreams: 1 campaner_m_me_araca_int.pdf: 1059060 bytes, checksum: 600ec274c934bb60162a9d4fc4bbf5be (MD5) / Made available in DSpace on 2019-01-30T13:03:21Z (GMT). No. of bitstreams: 1 campaner_m_me_araca_int.pdf: 1059060 bytes, checksum: 600ec274c934bb60162a9d4fc4bbf5be (MD5) Previous issue date: 2019-01-18 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Os pacientes com maxila atrófica ainda representam um problema complexo para os cirurgiões dentistas, tornando sua reabilitação um grande desafio, devido à baixa quantidade e qualidade óssea, e também de áreas anatômicas a serem preservadas como a fossa nasal e o seio maxilar que pode apresentar-se pneumatizados. O objetivo deste estudo foi avaliar a distribuição de tensões qualitativa e quantitativamente, por meio da análise fotoelástica (AF) e extensométrica (AE), de três diferentes protocolos alternativos ao procedimento de enxertia óssea para a reabilitação implantossuportada de maxila atrófica: implante convencional (S- standard - 3,75x11,5mm) associado a implante curto (C) (5x7mm), implante convencional (S) associado a implante inclinado em 30º e dois implantes convencionais instalados no eixo axial utilizando prótese com extensão em cantilever. A partir de um protótipo da maxila edêntula com atrofia na região posterior, confeccionada por meio de um modelo digital 3D, os corpos de prova foram divididos em 04 grupos de 01 espécime cada para AF e quatro grupos de 05 espécimes para a AE. Foram confeccionados 24 modelos, destes 4 foram de resina fotoelástica (PL-2) e 20 de poliuretano (F160). Foram utilizados implantes do tipo cone morse e confeccionadas próteses fixas implantossuportadas múltiplas (14-16) parafusadas. Os grupos foram divididos de acordo com protocolo de reabilitação proposto em: ISA - dois implantes (S) paralelos ao eixo axial, sendo um instalado na região do primeiro pré-molar (14) e outro na região do primeiro molar (16); ISAICA - dois implantes instalados paralelos ao eixo axial, sendo um implante (S) na região do primeiro pré-molar (14) e um implante curto (C) na região do primeiro molar (16); ISAISI - dois implantes (S), sendo um paralelo ao eixo axial instalado na região do primeiro pré-molar (14) e outro com inclinação distal de 30° na região do primeiro molar (16) e ISAPC - dois implantes (S) paralelos ao eixo axial instalados na região do primeiro pré-molar (14) e segundo pré-molar (15), com o pôntico (16) em cantiliever. Para AF, o conjunto modelo fotoelástico/implante/prótese foi posicionado em um polariscópio circular associado a uma máquina de ensaio universal (EMIC), sendo aplicada força axial de 100N. As tensões geradas foram registradas fotograficamente e analisadas qualitativamente. Para AE, 6 extensômetros foram posicionados ao redor dos dois implantes de cada grupo. Os sinais elétricos foram captados por um aparelho de aquisição de dados (ASD2002). Os dados quantitativos foram submetidos a ANOVA e ao teste Tukey (P<0.005). Pela AF, os protocolos de tratamento ISAICA e ISAPC apresentaram maior número de franjas de alta tensão em comparação os protocolos ISAISI e ISA. Pela AE, os protocolos ISAICA e ISAPC apresentaram maiores valores de tensão (microstrain), sendo diferentes do grupo controle ISA (P<.005). Já o protocolo ISAICA não apresentou diferença do grupo controle. Conclui-se que o protocolo de reabilitação de maxila atrófica com associação de implante axial e implante com inclinação distal de 30° apresentou o melhor comportamento biomecânico, sendo considerado a melhor alternativa ao procedimento de enxertia óssea para a reabilitação implantossuportada de maxila atrófica. / Patients with atrophic maxillary still represent a challenge to rehabilitate for dentists in general due to limitations on bone quantity and quality and the anatomical setting of the sites to be preserved, such as nasal cavity and maxillary sinus, that could be pneumatized. The aim of this study was to assess qualitative and quantitative the stress distribution, through photoelastic analysis (PA) and strain gauge (SG), of three alternative techniques to bone augmentation procedures for implant placement: standard implant (S- standard - 3,75x11,5mm) associated to short implant (C) (5x7mm), standard implant (S) associated to 30 º tilted implant, two conventional implants placed in the long axis and a cantilever prosthesis. A maxillary prototype model, with posterior atrophic region, was manufactured from a digital 3D model and divided into four groups with 01 specimen for the PA and 05 specimen for the SG. A total of 24 models were manufactured, 4 from photoelastic resin (PL-2) and 20 from polyurethane (F160). Morse taper implants were used and multiple screwed implant supported prostheses were manufactured (14-16). The groups were divided according to the rehabilitation protocol: ISA – two parallel implants in the long axis (S), one in the pre-molar region (14) and in the molar region (16); ISAICA – two parallel implants in the long axis, one standard (S) in the pre-molar region (14) and one short (C) in the molar region (16); ISAISI – two standard implants, one parallel to the long axis (14) and one tilted at 30˚ (16) and ISAPC – two parallel implants in the long axis, in the first (14) and second (15) pre molar region, with a cantilever prostheses (16). For the PA, the assemble photoelastic model/implants/prostheses was positioned in a circular polariscope associated to a universal test machine (EMIC), and an axial load of 100N applied. The tension generated were photographed and analyzed qualitatively. For the SGA, 6 extensometers were attached around two implants of each group. The electoral signals were captured with a data acquisition machine (ASD2001). The data were submitted to ANOVA and Tukey test (P <0.005). By AF, the ISAICA and ISAPC treatment protocols presented higher number of high-voltage fringes compared to the ISAISI and ISA protocols. By the AE, the ISAICA and ISAPC protocols presented higher values of tension (microstrain), being different from the ISA control group (P <.005). The ISAICA protocol did not present any difference in the control group. It was concluded that the protocol of atrophic maxilla rehabilitation with an association of axial implant and implant with distal inclination of 30 ° presented the best biomechanical behavior, being considered the best alternative to the bone grafting procedure for the implant-supported rehabilitation of atrophic maxilla.
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Estudo da correlação instrumental e sensorial de uma composição aromática aplicada na pele em função do ciclo menstrual / Study of instrumental and sensory correlation of a aromatic composition on the skin in function of mentrual cycle.

Claudia Silva Cortez Pereira da Costa 19 December 2013 (has links)
A área de perfumaria no mundo vem se desenvolvendo a cada dia buscando maior conhecimento das matérias-primas aromáticas, desde suas reações, estabilidade até suas interações com o substrato onde é aplicado, sempre em busca do conhecimento de todas as variáveis que possam influenciar a relação perfume-substrato e a aceitação dos consumidores, medida por meio da avaliação sensorial. Apesar de muitos estudos sobre a relação perfume-pele, poucos envolveram a relação com ciclo menstrual. Neste estudo o objetivo foi correlacionar às análises sensorial e instrumental (medidas biomecânicas e cromatográficas), estudar as matérias-primas aromáticas em função do ciclo menstrual. O estudo envolveu indivíduos com idade entre 18-40 anos: 29 mulheres e 3 homens, estes usados como grupo controle. Cada voluntária teve 40 &#181;l da composição aromática Ciclo 1910 aplicado no antebraço, onde foram feitas as medidas biomecânicas (corneometria, sebumetria e TEWL) nos tempos inicial e 6h. Nos tempos inicial, 1.5h, 3h, 4,5h e 6h se auto-avaliaram sensorialmente a intensidade de perfume por meio de escala sensorial de magnitude rotulada (LMS) e foram coletados os compostos aromáticos liberados pela técnica de headspace e analisados por espectrometria com cromatografia a gás e detetor de massa (CGMS). Realizou-se também medidas biomecânicas de corneometria, sebumetria e TEWL interescapulares em 5 voluntárias nos tempos inicial e 6h para comparação. Os resultados obtidos foram que as fases do ciclo não interferiram nas variáveis biomecânicas (p>0,05) quando analisadas isoladamente. Para as medidas realizadas no antebraço, os índices de Corneometria (p<0,001) e TEWL (p: 0,011) na região tratada apresentou média maior que a do controle. A média dos índices de Corneometria e Sebumetria da região do antebraço tratada foi menor (p<0,001) que da região interescapular. Na análise cromatográfica não houve um padrão de resposta em diferentes fases do ciclo. As correlações entre a avaliação sensorial e instrumental (cromatografia e propriedades biomecânicas) não observaram nenhum nível de correlação (p>0,05). A Cromatografia (dados cromatográficos) foi maior na fase Folicular que nas fases Menstrual e Ovulatória (p=0,003), ao considerar como variável resposta em função do ciclo menstrual e da avaliação sensorial. Houve uma forte correlação positiva entre a análise sensorial e a avaliação na pele do homem (p<0,001). No entanto, o fator intrínseco do indivíduo Mulher influenciou na resposta, ocasionando grande variabilidade, porém percebeu-se claramente que os hormônios sexuais interferiram na resposta sensorial, cromatográfica e biomecânica da pele. / The perfumery in the world has been developed everyday bringing more knowledge about aromatic raw-materials, as from chemistry reactions, stability until their interactions with substrate where is applied, always looking for variables could influence in the relation perfume-substrate and consumer acceptability, measured by sensory evaluation. Despite a lot of studies were done on this subject, few involved effects as function of menstrual cycle. The aim of this study was to correlate sensory and instrumental analysis (biomechanical and chromatographic measurements), to study the olfactory profile of raw materials in function of menstrual cycle. The study involved people with 18-40 years old: 29 volunteers, three men, who were used as control group. Each volunteer had 40 &#181;l of perfume applied on forearm, where were done Biomechanical measurements (Corneometer, Sebumeter and TEWL) at initial and 6h, At time initial, 1.5h, 3h, 4.5h and 6h; they did self-sensory assessment in perfume intensity in own forearm using labeled magnitude scale (LMS) and also where aromatic compounds released were collected by headspace technique spectrometry and gas chromatography with mass detector (CGMS). In addition, it was done biomechanical measurements (Corneometer, Sebumeter and TEWL) on interscapular region at initial and 6h for comparing. Resulting that the phases of the cycle did not affect the biomechanical variables (p > 0.05) when analyzed individually. For measurements in the forearm, Corneometry index (p < 0.001) and TEWL (p=0.011) in the treated area were higher than the control. The average of the Sebumetry, Corneometry indexes of the forearm treated was lower (p <0.001) than the interscapular region. In the analysis of chromatographic, there was a standard response at different stages of the menstrual cycle, however the analysis by individual had no a pattern response to the release of aromatic compounds. The correlations between sensory and instrumental (chromatography and biomechanical properties) did not observe any correlation (p> 0.05). But when considering chromatography as the response variable as a function of the menstrual cycle and the sensory evaluation, the follicular phase was higher than the Menstrual and Ovulatory phase (p=0.003). There was a strong positive correlation between sensory analysis and evaluation on men skin (p<0.001). However, the intrinsic factor of the individual woman influenced the response, leading to large response variability; however, see clearly that sex hormones interfere in the sensory response, chromatographic and biomechanics of the skin.

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