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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.
401

Étude des adaptations spécifiques à la pratique des activités d'armer : facteurs de risque et prévention des pathologies de l'épaule / Study of specific adaptations to overhead sports : risk factor and prevention of shoulder injuries

Gillet, Benoit 10 December 2018 (has links)
Le complexe articulaire de l'épaule est extrêmement sollicité au cours de la pratique du tennis. Le service, notamment, impose des contraintes mécaniques importantes et requiert des positions articulaires extrêmes plaçant l'épaule dans des situations à risque de blessures. La pratique intensive du tennis conduit à des adaptations musculo-squelettiques et fonctionnelles qui seraient bénéfiques à la performance. Cependant, il est difficile de savoir quand elles deviennent excessives ou déséquilibrées ce qui augmenterait les risques de blessures. Alors que la détection des futurs talents commence dès 5-6 ans, peu d'informations sur les caractéristiques de leur épaule, des facteurs de risque de blessures et de la pathomécanique spécifique sont actuellement disponibles. De telles connaissances seraient utiles pour optimiser leur prise en charge par les entraîneurs. L'objectif de ce travail de thèse était de caractériser l'épaule du jeune joueur de tennis, d'identifier des facteurs de risque de blessures et décrire la pathomécanique de l'épaule en lien avec le service du tennis. Afin de caractériser l'épaule du jeune joueur de tennis, 67 joueurs de tennis asymptomatiques âgés de 7 à 13 ans ont été répartis en trois groupes en fonction de leur âge biologique. En comparant les amplitudes articulaires et les forces des muscles de l'épaule, il a été observé que ces caractéristiques musculo-squelettiques s'adaptaient dès le plus jeune. Par la suite, afin d'identifier des facteurs de risque de blessures à l'épaule, ces mêmes caractéristiques ont été comparées entre 31 joueurs avec antécédent de douleur et 60 joueurs asymptomatiques. Les joueurs avec antécédent de douleur présentaient une plus grande amplitude de rotation de l'articulation glénohumérale ainsi qu'une faiblesse des muscles rotateurs externes de l'articulation glénohumérale et des muscles fixateurs de la scapula. Cependant, il restait difficile de savoir si ces maladaptations étaient la cause ou la conséquence de la blessure à l'épaule. Un suivi longitudinal par les analyses de transitions des profils latents a été réalisé pour apporter un éclairage. Par ailleurs, afin de mieux décrire la pathomécanique de l'épaule en lien avec le service, la cinématique des articulations glénohumérale et scapulothoracique enregistrée lors du service a été comparée entre 13 joueurs sans antécédent de douleur et 15 avec antécédent de douleur. Ces joueurs avec antécédent de douleur modifiaient leur cinématique glénohumérale et scapulothoracique à la fin de la phase d'armer du service afin probablement d'éviter la douleur et de poursuivre leur pratique du tennis. Enfin, l'étude précédente a été complétée par une analyse biomécanique du service avant et après affaiblissement du trapèze inférieur par fatigue avec électrostimulation. La faiblesse des fixateurs de la scapula, décrite chez des joueurs avec antécédent de douleur, conduisait à une cinématique scapulaire inappropriée et une diminution d'activation des muscles antérieurs de l'épaule pouvant mettre en péril les structures anatomiques du complexe articulaire de l'épaule. Ces résultats apportent des informations essentielles pour améliorer la qualité des entraînements et la prévention des blessures à l'épaule chez les jeunes joueurs de tennis. Ils soulignent notamment l'importance d'un travail de renforcement des muscles stabilisateurs de l'épaule (muscles rotateurs de l'articulation glénohumérale et stabilisateurs de la scapula) / The shoulder joint complex is largely involved in the tennis strokes. Particularly, the tennis serve applies high mechanical constraints and requires extreme joint positions making the shoulder vulnerable to injuries. Intensive tennis practice leads to musculoskeletal and functional adaptations that are thought to be beneficial to performance. However, it remains unclear when they become unbalanced or excessive that increases the risk of injury. The prospects are scouted from 5 years old, but little is known on their specific shoulder characteristics, risk factors for injury and pathomechanics. Such knowledge would be useful to optimize their monitoring by coaches. This thesis aimed to characterize the young tennis player's shoulder, identify risk factors for injury and describe the shoulder pathomechanisms related to the tennis serve. To characterize the young tennis player’s shoulder, 67 asymptomatic tennis players aged 7 to 13 years old were divided into three groups according to their biological age. The comparison between our three groups highlighted that the glenohumeral ranges of motion and the shoulder muscle strength adaptions occurred from an early age. Then to bring risk factor for shoulder injuries to light, these parameters were also compared between 31 players with a history of shoulder pain and 60 asymptomatic players. Players with a history of shoulder pain presented a larger glenohumeral joint total rotation range of motion as well as a weakness of the glenohumeral external rotator muscles and the scapular stabilizer muscles. A longitudinal study, using a latent profile transition analysis, was conducted to determine whether the factors previously identified were the cause or consequence of the shoulder injury. Furthermore, in the aim to describe the shoulder pathomechanisms related to the tennis serve motion, the glenohumeral and scapulothoracic kinematics of the tennis serve were compared between 13 players without and 15 with a history of shoulder pain. Players with a history ofshoulder pain adapted their glenohumeral and scapulothoracic kinematics at the end of the cocking phase to probably preserve the sub-acromial space and the rotator cuff tendons during the tennis serve. Finally, the previous study was completed by a study analyzing the shoulder biomechanics of a tennis serve before and after the fatigue of the lower trapezius. The weakness of the scapular stabilizer muscles impaired the scapular kinematics and decreased the activation of the anterior shoulder muscles that may jeopardize the shoulder joint anatomical structures. These findings bring new knowledge to improve the young players monitoring and the injury prevention. Particularly, it highlights the importance to strengthen the stabilizer muscles (glenohumeral external rotator muscles and scapular stabilizer muscles)
402

Estudo sobre a intervenção fisioterapêutica precoce e tardia na morbidade de membro superior pós-tratamento de câncer de mama / The physiotherapy intervention in the morbidities after breast cancer treatment.

Marx, Angela Gonçalves 04 January 2007 (has links)
INTRODUÇÃO: O tratamento do câncer de mama está associado à morbidade do membro superior, com complicações que têm um impacto significante na qualidade de vida das pacientes. O OBJETIVO deste trabalho foi traçar um protocolo de tratamento fisioterapêutico para prevenir as morbidades após cirurgia de câncer de mama. CASUÍSTICA E MÉTODOS: Este estudo avaliou 132 mulheres com a intervenção da fisioterapia em dois momentos: no primeiro pós-operatório (PO) e entre o 10º - 15º dia do PO. Reavaliações foram feitas nos meses 1, 2, 3, 4, 5, 6 e após um ano do PO. RESULTADOS: O grupo de intervenção precoce mostrou uma recuperação mais rápida da amplitude de movimentos e apresentou menor morbidade em relação ao grupo tardio. CONCLUSÃO: O protocolo fisioterapêutico preconizado, tanto precoce quanto tardio, é eficaz. A recuperação da função do membro superior e o menor índice de morbidades mostram que a fisioterapia deve sempre ser instituída nas pacientes que se submetem à cirurgia de câncer de mama. / INTRODUCTION: The breast cancer treatment is always linked with the morbidity of the upper limb with complications that will have an enormous impact in the quality of life of the patients submitted to breast cancer treatment. Objective : the objective of this study was to develop a physiotherapy protocol in order to prevent morbidities after breast cancer treatment METHODS: This study evaluated 132 patients submitted to physiotherapy sessions in two different moments: 1 st day post surgery and at the 10-15 th day . Follow-ups were made on months 1, 2, 3, 4, 5, 6 and after a year. RESULTS: The earlier group showed a faster recovery of arm range of motion and had less arm morbidity. CONCLUSÃO: O RESULTS: G1 showed a faster flexion and abduction ROM recovery and had less morbidity as compared to the other group. The arm circumferences in the early intervention group had lower values as compared to the late intervention group. CONCLUSION: The physiotherapy protocol used in the study showed its efficacy. The upper arm ROM was recovered and both groups had less arm morbidity.
403

Avaliação da amplitude de movimento da articulação coxofemoral como fator de risco etiológico para as lesões por não-contato do ligamento cruzado anterior do joelho em praticantes de futebol

Castro, Jacqueline Vieira de January 2008 (has links)
Objetivo: Investigar se há associação entre a diminuição da amplitude de movimento da articulação coxofemoral e a lesão por não-contato do ligamento cruzado anterior em jogadores de futebol. Método: Neste estudo de casos e controles, 50 jogadores de futebol, com lesão por nãocontato do ligamento cruzado anterior do joelho, confirmada por cirurgia, tiveram suas articulações coxofemorais examinadas e comparadas com o grupo controle. Os achados foram estatisticamente analisados, de acordo com dois pontos de corte (70° e 80°, na soma total de rotação interna e rotação externa), em ambos os grupos. Resultados: Uma significativa diminuição na amplitude de movimento da articulação coxofemoral foi encontrada em 38% de todos os indivíduos estudados no menor ponto de corte (70°) e 64% no maior ponto de corte (80°). A diminuição da amplitude de movimento do quadril foi maior no grupo com ruptura de LCA do que no grupo controle, com pequena diferença entre os dois pontos de corte (70° e 80°). A diferença entre pacientes e controles foi estatisticamente significativa (p = 0, 001). Conclusão: Houve uma forte associação entre a diminuição da amplitude de movimento da articulação do quadril e a ruptura de LCA em jogadores de futebol, não somente, mas, principalmente, devido à diminuição da rotação interna. Apesar da falta de comparação com outros esportes, o resultado mostrou um maior aumento da diminuição de amplitude de movimento do quadril no grupo de jogadores de futebol, quando comparado com a população em geral. / Purpose: To investigate whether there is an association between decreased hip range of motion and noncontact anterior cruciate ligament (ACL) injuries in soccer players. Methods: In this case-control study, 50 soccer players with noncontact ACL injuries confirmed by surgery had their hips examined and compared with those of a control group. Findings were statistically analyzed according to cutoff points (70 and 80 degrees of total internal-external rotation sum) for both groups. Results: A significant decrease in hip range of motion was found in 38% of all individuals studied at the lower cutoff point (70 degrees) and 64% at the upper cutoff point (80 degrees). The decrease in hip range of motion was greater in the group with ruptured ACL than in controls, with little difference between the two cutoff points (70 and 80 degrees). The difference between patients and controls was statistically significant (p < 0,001). Conclusions: There was strong association between decreased hip range of motion and ACL ruptures in soccer players, not only but mainly due to internal rotation lessening. Despite lacking comparison with other sports, our findings showed a higher decrease of hip range of motion in the group of soccer players when compared with the general population.
404

"Avaliação do tratamento fisioterapêutico da doença de Legg-Calvé-Perthes" / "Evaluation of physiotherapy in the treatment of Legg-Calvé-Perthes disease"

Brech, Guilherme Carlos 25 May 2006 (has links)
O objetivo do trabalho foi avaliar clinicamente os possíveis efeitos dos exercícios fisioterapêuticos propostos em comparação com o acompanhamento observacional dos pacientes com DLCP. Foi um estudo prospectivo controlado incluindo 20 pacientes com DLCP unilateral, divididos em dois grupos: grupo A, acompanhamento observacional e grupo B, acompanhamento fisioterapêutico. Foram avaliados os parâmetros: amplitude de movimento articular (ADM), o grau de força muscular e o grau de disfunção articular e o quadro radiográfico, pré e pós-tratamento. Houve no grupo B uma melhora significativa da ADM do quadril, enquanto no grupo A ocorreu uma piora. A força muscular também melhorou no grupo B, enquanto no grupo A não houve alteração. O grau de disfunção articular apresentou, uma melhora significativa no grupo B e uma piora no grupo A. O tratamento fisioterapêutico empregado no grupo B foi eficaz para os pacientes com DLCP. / The purpose of the present study was to clinically evaluate possible effects of the proposed physiotherapeutic exercises compared to observational follow-up in LCPD patients. A prospective follow-up study with control group was conducted with 20 unilateral LCPD patients divided into two groups: group A (observational follow-up) and group B (physiotherapeutic follow-up). The following parameters were assessed: articular range of motion (ROM), level of muscular strength, level of articular dysfunction, and radiographic status, both before and after the treatment. Group B showed significant ROM improvement of the hip, while in group A worsening occurred. Muscular strength also improved in group B, while group A showed no changes. The level of articular dysfunction showed significant improvement in Group B and worsening in group. The physiotherapeutic treatment (group B) was efficient for patients with LCPD.
405

Effects of Rise/Fall Time on VEMP Amplitude and Latency

Howard, J., Akin, Faith W., Murnane, Owen D., Tampas, J., Clinard, C. 01 January 2005 (has links)
No description available.
406

Importance of atomic force microscopy settings for measuring the diameter of carbon nanotubes / Betydelsen av atomkraftmikroskåpets inställningar för mätningar av diametern hos kolnanorör

Almén, Anton January 2019 (has links)
Carbon nanotubes (CNTs) have gathered a lot of interest because of their extraordinary mechanical, electrical and thermal properties and have potential applications in a wide variety of areas such as material-reinforcement and nano-electronics. The properties of nanotubes are dependent on their diameter and methods for determining this using atomic force microscopy (AFM) in tapping mode assume that the measured height of the tubes represent the real diameter. Based on early, faulty calculations, the forces in tapping mode were assumed to be much lower than in contact mode, however it was later shown that forces in tapping mode can at point of impact rival the forces present in contact mode. This means that there is a potential risk of tube deformation during tapping mode measurements, resulting in incorrectly determined diameters. This work studies CNTs deposited on a silicon-substrate to analyze the effect of three common AFM settings (tapping frequency, free oscillation amplitude and setpoint) to determine their effect on measured CNT diameters and recommendations for choosing settings are given. / Kolnanorör har skapat mycket intresse på grund av sina extraordinära mekaniska, elektriska och termiska egenskaper och har lovande tillämpningar inom en mängd olika områden så som materialförstärkning och nanoelektronik. Kolnanorörens egenskaper påverkas kraftigt av deras diameter och de metoder som använder sig av atomkraftsmikroskopi(AFM) för att mäta diametern hos rören antar att den höjd-data man får fram är ett bra mått på den verkliga diametern hos rören. Baserat på tidiga, felaktiga beräkningar, antog man att kraften i ’tapping mode’ skulle vara mycket lägre än i ’contact mode’ vilket skulle leda till att man inte deformerar ytan man undersöker. Senare forskning visade att kraften mellan spets och prov kan vara lika stor eller rentutav större i tapping mode än i contact mode under det ögonblick då spetsen slår ner i provytan. Det medför att det finns en potentiell risk för att man deformerar kolnanorören när man mäter på dom vilket skulle resultera i att man får felaktiga värden på deras diametrar. Under det här projektet har kolnanorör som placerats på ett kisel-substrat undersökts för att analysera hur tre vanliga inställningar hos AFMet påverkar de erhållna värdena för diametern hos kolnanorören. De tre inställningarna som testats är svängnings-frekvensen, svängnings-amplituden i luft och börvärdet hos svängnings-amplituden.
407

L'effet de la manipulation vertébrale sur la douleur provoquée expérimentalement / The effect of spinal manipulative therapy on experimentally induced pain

Millan, Mario 06 February 2014 (has links)
La manipulation vertébrale (MV) est l'une des options dans le traitement des douleurs d'origine neuromusculosquelettique. Ses indications ont été identifiées à partir de l'expérience des professionnels qui l'utilisent, ainsi que des études épidémiologiques autour de ses résultats cliniques. Cependant, son mécanisme d'action précis demeure à ce jour inexpliqué.La littérature scientifique sur ce sujet est incomplète, éparse et confuse. Certains auteurs et professionnels proposent des hypothèses des mécanismes d'action neurobiologiques et d'autres biomécaniques. De plus, l'étude de la douleur rend la situation difficile en raison de la complexité des situations cliniques et des traitements associés dont les patients bénéficient. C'est la raison pour laquelle l'objectif de cette thèse est d'étudier si la MV a un effet sur la douleur provoquée de manière expérimentale. Si tel est le cas, il importe de savoir s'il est systémique ou locorégional et dans cette dernière hypothèse, si ce résultat est le produit d'une action directe de la MV sur la douleur ou secondaire à une amélioration du mouvement. N'ayant pas trouvé d'étude englobant la problématique mixte des effets de la MV sur la douleur et le mouvement, nous avons procédé à deux revues systématiques et critiques de la littérature scientifique ; l'une a porté sur son effet sur la douleur et l'autre sur l'amplitude du mouvement des segments vertébraux. Dans la première, nous avons rassemblé 22 articles décrivant 43 essais cliniques montrant un effet hypoalgésique de la MV au niveau locorégional, mais les résultats diffèrent selon la manière dont la douleur a été provoquée. Nous n’avons pas pu tirer de conclusion sur l'action systémique de la MV du fait de la qualité des articles sur ce sujet. Quant à la revue de la littérature réalisée sur l'effet de la MV sur l'amplitude du mouvement, l'étude de 15 articles ne nous a pas permis de prouver l'efficacité de cette technique pour augmenter l'amplitude des mouvements segmentaires, malgré des limitations à prendre en considération, notamment le fait que ces études ont été réalisées sur des volontaires sains et non sur des patients avec une mobilité réduite. A partir de là, nous concluons que l'effet de la MV sur la douleur est plutôt direct, et défendons la thèse que l'hypoalgésie induite par la MV permet l'amélioration et la récupération de la fonction de mouvement, et non l'inverse.Cependant, même si nous répondons à nos questions de recherche, ces réponses demeurent partielles et le sujet reste à approfondir. Nos deux revues indiquent qu’il reste à clarifier : les mécanismes exacts des effets de la MV sur la douleur, la durée des effets, les rapports "dose/effet", l'identification des techniques les plus efficaces, ou encore, sur le ciblage plus fin des patients à traiter. Il en est de même en ce qui concerne l'étude de l'effet de la MV sur l'amplitude du mouvement, où il manque notamment des études réalisées sur des patients et des personnes présentant des mouvements limités. Des améliorations sont également à prévoir dans la coordination des chercheurs les rassemblant autour d'une politique de recherche partagée sur le long/moyen terme, et à partir d'un consensus méthodologique, particulièrement en termes de suivi des essais, d'unités de mesures, de précision des critères de qualité des essais, de promotion de méta-analyses, etc. Au total, si la MV semble avoir un effet direct sur la douleur, il n’en demeure pas moins que la connaissance détaillée de ses mécanismes et des modalités d'application dans la pratique clinique reste à approfondir, ce qui pourrait devenir un véritable enjeu pour la communauté des chercheurs, des enseignants et des cliniciens. / Spinal manipulative therapy (SMT) is one of the treatments used to reduce musculoskeletal pain. Some clinical studies have shown that it really has a pain reducing effect but the indications for when it should be used is mainly based on clinical experience and logic. Further, although SMT is widely used, the precise mechanisms of action that can explain how it works, are unknown.We noticed that the scientific literature on this subject is incomplete, scattered and confused. In relation to the mechanisms, some authors propose a number of neurobiological mechanisms (such as a direct reduction of pain) whereas others are convinced that the mode of action is biomechanical (such as improved range of motion). For this reason, when trying to find out if SMT has a pain reducing effect, a better alternative is to start with healthy people, provoke a pain experimentally, perform the SMT, and measure their pain, to see if it has improved with the “treatment”. If it would be possible to see if SMT does have a pure pain reducing effect, then it would be important to find out if this effect is only regional, in the area of the manipulation, or if this effect is systemic. Also, none of the authors who proposed the biomechanical theory offered any evidence that improved movement results in less pain, but then, the opposite pathway (reduce pain first, better movement after) has not been shown either, by these proponents of theories. For this reason we decided to study the already existing scientific literature in a critical and systematic fashion.Unfortunately, we did not find any study including the mixed problem of the effects of SMT on pain and movement, we therefore performed two systematic reviews of the scientific literature: one focused on its effect on experimental pain and the other on its effect on the range of motion (ROM) of the vertebral segments. In the first one, we collected 22 articles describing 43 trials showing an hypoalgesic effect of the locoregional level. Interestingly, the results differ depending on how the pain was provoked. We were not been able to reach a conclusion on the systemic action of the SMT because of the lack of quality of articles on this topic. Concerning the literature review on the effect of SMT on ROM, the review of 15 research articles did not allow us to « prove » the effectiveness of this technique to increase the range of segmental motion. There were some limitations with these studies, such as the fact that they had been performed in healthy volunteers and not in people with reduced mobility. In sum, we could conclude that the effect of SMT on pain has been clearly shown, which supports the hypothesis that the hypoalgesia induced by SMT allows the improvement and recovery of function of movement, and not the inverse. These results have been reported in our two scientific articles.However, even if we were able to obtain answers to our research questions, these answers are incomplete and the subject remains to be further explored. There are still questions that remain to be clarified, such as: What are the exact effects of SMT on pain mechanisms? How long does the effect remain ? Is there a " dose / effect "? Which are the most effective SMT techniques? and How should patients be best targeted for this treatment ? Does SMT have an effect on ROM on people with limited movement?Finally, a coordination of research is necessary to move forward more effectively. Researchers would need to gather around a shared policy in relation to the medium / long term research, and from a methodological consensus. In conclusion, SMT does seem to have a direct effect on pain. However, we need some more and detailed knowledge of the mechanisms and procedures before we can really apply this knowledge efficiently in clinical practice. No doubt, this could become an important issue for the community of researchers, teachers and clinicians.
408

Acute and Chronic Adaptations To Intermittent and Continuous Exercise in Chronic Obstructive Pulmonary Disease Patients

Sabapathy, Surendran, n/a January 2006 (has links)
The primary aim of this thesis was to develop a better understanding of the physiology and perceptual responses associated with the performance of continuous (CE) and intermittent exercise (IE) in patients with moderate chronic obstructive pulmonary disease (COPD). A secondary aim was to examine factors that could potentially limit exercise tolerance in COPD patients, particularly in relation to the dynamics of the cardiovascular system and muscle metabolism. The results of the four studies conducted to achieve these aims are presented in this thesis. In Study 1, the physiological, metabolic and perceptual responses to an acute bout of IE and CE were examined in 10 individuals with moderate COPD. Each subject completed an incremental exercise test to exhaustion on a cycle ergometer. Subjects then performed IE (1 min exercise: 1 min rest ratio) and CE tests at 70% of peak power in random order on separate days. Gas exchange, heart rate, plasma lactate concentration, ratings of breathlessness, inspiratory capacity and the total amount of work completed were measured during each exercise test. Subjects were able to complete a significantly greater amount of work during IE (71 ± 32 kJ) compared with CE (31 ± 24 kJ). Intermittent exercise was associated with significantly lower values for oxygen uptake, expired ventilation and plasma lactate concentration when compared with CE. Subjects also reported a significantly lower rating of breathlessness during IE compared to CE. The degree of dynamic lung hyperinflation (change in end-expiratory lung volume) was lower during IE (0.23 ± 0.07 L) than during CE (0.52 ± 0.13 L). The results suggest that IE may be superior to CE as a mode of training for patients with COPD. The greater amount of total work performed and the lower measured physiological responses attained with intermittent exercise could potentially allow greater training adaptations to be achieved in individuals with more limited lung function. The purpose of Study 2 was to compare the adaptations to 8 wk of supervised intermittent and continuous cycle ergometry training, performed at the same relative intensity and matched for total work completed, in patients with COPD. Nineteen subjects with moderate COPD were stratified according to age, gender, and pulmonary function, and then randomly assigned to either an IE (1 min exercise: 1 min rest ratio) or CE training group. Subjects trained 3 d per week for 8 wk and completed 30 min of exercise. Initial training intensity, i.e., the power output applied during the CE bouts and during the exercise interval of the IE bouts, was determined as 50% of the peak power output achieved during incremental exercise and was increased by 5% each week after 2 wk of training. The total amount of work performed was not significantly different (P=0.74) between the CE (750 ± 90 kJ) and IE (707 ± 92 kJ) groups. The subjects who performed IE (N=9) experienced significantly lower levels of perceived breathlessness and lower limb fatigue during the exercise-training bouts than the group who performed CE (N=10). However, exercise capacity (peak oxygen uptake) and exercise tolerance (peak power output and 6-min walk distance) improved to a similar extent in both training groups. During submaximal constant-load exercise, the improved (faster) phase II oxygen uptake kinetic response with training was independent of exercise mode. Furthermore, training-induced reductions in submaximal exercise heart rate, carbon dioxide output, expired ventilation and blood lactate concentrations were not different between the two training modes. Exercise training also resulted in an equivalent reduction for both training modes in the degree of dynamic hyperinflation observed during incremental exercise. Thus, when total work performed and relative intensity were the same for both training modes, 8 wk of CE or IE training resulted in similar functional improvements and physiological adaptations in patients with moderate COPD. Study 3 examined the relationship between exercise capacity (peak oxygen uptake) and lower limb vasodilatory capacity in 9 patients with moderate COPD and 9 healthy age-matched control subjects. While peak oxygen uptake was significantly lower in the COPD patients (15.8 ± 3.5 mL·min-1·kg-1) compared to the control subjects (25.2 ± 3.5 mL·kg-1·min-1), there were no significant differences between groups in peak calf blood flow or peak calf conductance measured 7 s post-ischemia. Peak oxygen uptake was significantly correlated with peak calf blood flow and peak conductance in the control group, whereas there was no significant relationship found between these variables in the COPD group. However, the rate of decay in blood flow following ischemia was significantly slower (p less than 0.05) for the COPD group (-0.036 ± 0.005 mL·100 mL-1·min-1·s-1) when compared to the control group (-0.048 ± 0.015 mL·100 mL-1·min-1·s-1). The results of this study suggest that the lower peak exercise capacity in patients with moderate COPD is not related to a loss in leg vasodilatory capacity. Study 4 examined the dynamics of oxygen uptake kinetics during high-intensity constant-load cycling performed at 70% of the peak power attained during an incremental exercise test in 7 patients with moderate COPD and 7 healthy age-matched controls. The time constant of the primary component (phase II) of oxygen uptake was significantly slower in the COPD patients (82 ± 8 s) when compared to healthy control subjects (44 ± 4 s). Moreover, the oxygen cost per unit increment in power output for the primary component and the overall response were significantly higher in patients with COPD than in healthy control subjects. A slow component was observed in 5 of the 7 patients with COPD (49 ± 11 mL·min-1), whereas all of the control subjects demonstrated a slow component of oxygen uptake (213 ± 35 mL·min-1). The slow component comprised a significantly greater proportion of the total oxygen uptake response in the healthy control group (18 ± 2%) than in the COPD group (10 ± 2%). In the COPD patients, the slow component amplitude was significantly correlated with the decrease in inspiratory capacity (r = -0.88, P less than 0.05; N=5), indicating that the magnitude of the slow component was larger in individuals who experienced a greater degree of dynamic hyperinflation. This study demonstrated that most patients with moderate COPD are able to exercise at intensities high enough to elicit a slow component of oxygen uptake during constant-load exercise. The significant correlation observed between the slow component amplitude and the degree of dynamic hyperinflation suggests that the work of breathing may contribute to the slow component in patients with COPD.
409

Étude cinématique tridimensionnelle du rachis cervical. Comparaison entre sujets Asymptomatiques et pathologiques

Boussion, Luc 25 November 2008 (has links) (PDF)
Les cervicalgies constituent un enjeu médico-économique pour nos sociétés. Ceci justifie des recherches actives sur le rachis cervical afin de mieux appréhender les fondements des cervicalgies et fournir aux cliniciens des pistes permettant d'en prévenir les effets ou d'améliorer les traitements. Cette étude, qui inclut 66 sujets Asymptomatiques et pathologiques (arthrodèses, prothèses, whiplash), présente un protocole expérimental original et non invasif pour mesurer in vivo la cinématique tridimensionnelle de la tête par rapport au thorax. Elle quantifie les amplitudes angulaires des degrés de liberté principaux et couplés pour les mouvements de flexion-extension, d'inclinaison latérale, de rotation axiale et des mouvements complexes ainsi que les mouvements compensatoires des épaules. L'objectif final de ce travail est la comparaison entre les différentes populations
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Mesure de l'amplitude de transition b en u et de la phase CKM gamma a l'aide des desintegrations B0 en D0K*0 reconstruites avec l'experience Babar

Sordini, V. 06 June 2008 (has links) (PDF)
Cette these porte sur l'etude de la violation de CP dans le secteur des mesons B et en particulier les mesures de l'angle gamma du Triangle d'Unitarite, en utilisant les donnees enregistrees par le detecteur Babar. L'angle gamma est la phase relative entre les elements Vub et Vcb de la matrice CKM.<br />Un parametre tres important dans les mesures de gamma est le rapport r entre les amplitudes des desintegrations qui comportent une transition des quarks b en u et les desintegrations qui comportent une transition b en c. La sensibilite a gamma est proportionelle a la valeur de ce parametre. Dans la premiere partie de cette these, les problematiques liees a l'etude de l'angle gamma ainsi que l'etat actuel des mesures sont presentes.<br />Le travail experimental est ensuite presente, il comporte deux analyses en utilisant les desintegrations B0 en D0(barD0)K*0. Dans la premiere analyse, le canal B0 en D0(barD0)K*0 est etudie en utilisant une methode ADS et les mesons D neutres sont reconstruits dans les etats finals K+pi-, K+pi-pi0 et K+pi-pi+pi- et complexes conjugues.Cette analyse permet de mesurer le rapport r pour le canal B0 en D0K*0.<br />On obtient: r = 0.260+0.077-0.088. La grande valeur obtenue pour r rend l'utilisation de ce canal tres interessante pour les experiences presentes et futures, pour la determination de l'angle gamma.Dans la deuxieme analyse, le canal B0 en D0(barD0)K*0 est etudie avec une methode Dalitz et les mesons D neutres sont reconstruits dans l'etat final KSpi+pi-. Cette analyse permet une mesure de l'angle gamma. On obtient gamma = (162 +- 56) degrees avec une ambiguite de 180 degrees. La determination du parametre r par les deux analyses combinées est: r=0.259+0.073-0.079}. Ces analyses donnent les premiers resultats sur gamma et r obtenus a partir des etudes des mesons B neutres.<br />Finalement, des etudes de simulation, bases sur les donnees, sont presentes. Ces etudes montrent que l'utilisation des canaux B0 en D0(barD0)K*0 peut donner une sensitivite a gamma comparable avec celle des autres analyses, qui utilisent les mesons B charges.

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