L’Hypertrophie Ventriculaire Gauche (HVG) est actuellement mise en évidence par échographie. Cet examen fournit des informations anatomo-fonctionnelles mais ne permet pas de déterminer l’étiologie des HVG, ce qui engendre de graves erreurs de diagnostic et de prise en charge thérapeutique. Les HVG sont classiquement séparées en 2 catégories :1. pathologies hypertrophiques induites par la modification structurelle et fonctionnelle des cardiomyocites qui tend à compenser des insuffisances cardiaques liées par exemple à des problèmes d’hypertension artérielle, de rétrécissement aortique ou de CardioMyopathies Hypertrophiques sarcomériques ;2. pathologies infiltratives correspondant au dépôt de protéines dans la matriceextracellulaire principalement dues à différentes formes d’amyloses cardiaquesNotre hypothèse est que les différents mécanismes physiopathologiques (hypertrophique ou infiltratif) pourraient se traduire dans l’image par des propriétés spécifiques du speckle échographique. Nous avons donc développé un travail d’analyse de la texture de ces images afin de discriminer les différentes HVG.Dans cette étude, la base de données de 4795 images est divisée en une base d’apprentissage de 3770 images et une base de test de 1025 images. L’analyse de texture des images est faite par les ondelettes de Gabor avec 8 orientations, 7 tailles et 5 niveaux de décomposition. Ensuite, les caractéristiques statistiques de premier et deuxième ordre sont extraites des images. Le nombre des caractéristiques est réduit pour la base d’apprentissage en appliquant l’Analyse en Composantes Principales (ACP) suivie par l’analyse discriminante linéaire (ADL) pour une séparation supervisée des classes. Les caractéristiques extraites pour la base de test sont projetées sur les vecteurs propres sélectionnés au cours de l’apprentissage. L’ADL est appliquée à ce niveau pour la classification des données du test et la qualité de cette classification est évaluée. Les résultats obtenus sont bons (qualité totale de classification de 95,51%) et sont suivis d’une étape de cross-validation afin de vérifier la robustesse de notre méthode. A cette étape, les bases de données de l’apprentissage et du test sont mélangées et 50 combinaisons différentes sont évaluées. La même méthode décrite précédemment est appliquée. La cross-validation montre une variation de la qualité de classification (entre 30% et 99.96%) probablement due à l’hétérogénéité des caractéristiques texturelles pour les patients d’une même classe que l’on peut expliquer par des degrés différents d’avancement dans la pathologie.Ces travaux montrent qu’une analyse de texture des images échocardiographiques peut permettre de déterminer des bio-marqueurs aptes à discriminer différentes cardiopathies qui s’expriment par une HVG. Ce résultat peut avoir des retombées très importantes dans la détection précoce des amyloses cardiaques, maladies engendrant un fort taux de mortalité souvent dû à un retard de diagnostic et prise en charge des patients par un centre expert / Left-Ventricular Hypertrophy (LVH) is currently detected through echocardiography. The latter imaging modality provides anatomical and functional information. However, it does not allow the determination of the HVG etiology. This can, in turn, lead to dangerous errors in the diagnosis and treatment planning of the disease. LVH pathologies are separated into two categories:- Hypertrophic pathology caused by the structural and functional modification of cardiomyocytes that lead to cardiac failure related, for example, to arterial hypertension problems, aortic narrowing or sarcomeric hypertrophic cardiomyopathies.- Infiltrative pathologies corresponding to protein deposits on the extracellular matrix, mainly due to different forms of cardiac amyloidosisOur hypothesis is that different physiopathological mechanisms (hypertrophic or infiltrative) can be translated in the image through properties specific to echographic speckle. We have therefore developed the work of texture analysis of such images in order to discriminate the different types of LVH.In this study, the database of 4795 images is divided into a learning database of 3770 images and another testing database of 1025 images. The textural analysis of these images is done using Gabor wavelets with 8 orientations, 7 sizes and 5 decomposition levels. Next, the statistical characteristics of first and second orders are extracted from the filtered images. The number of characteristics is reduced for the learning database by applying Principal Component Analysis (PCA) followed by Linear Discriminant Analysis (LDA) for a supervised separation of the classes. The extracted characteristics for the test database are projected on the eigenvectors selected in the learning step. LDA is applied at this level for the test data classification, and the quality of this classification is evaluated. The obtained results are good (total classification quality of 95.51%). A step of cross-validation follows in order to verify the robustness of our method. At this stage, the learning and testing databases are mixed, and 50 different combinations are evaluated. The same method described previously is then applied. The cross-validation shows a variation in the classification quality (between 30% and 99.96%) probably due to the heterogeneity of the texture characteristics for the patients of the same class explained by different disease advancement stages.This work shows that the textural analysis of echocardiographic images can permit the determination of bio-markers suitable to discriminate different LVH cardiopathies. Our results can have a very important impact on the early detection of cardiac amyloidosis, a pathology causing a considerable rate of mortality often due to a belated diagnosis and support by the centers of expertise

Les ballons pressurisés développés par le CNES sont des structures de 8,5 à 12 m de diamètre, qui permettent d’emmener dans la stratosphère des équipements scientifiques pour effectuer des expériences de longue durée. La durée de vie de ces ballons est conditionnée par leur comportement mécanique et notamment le comportement en fluage qui s’il est trop marqué, peut engendrer un changement d’altitude se traduisant alors par une augmentation importante de la contrainte dans la membrane. On observe aussi des défaillances des ballons au cours de leur lancement ou après une brève phase de vol (2 à 24 heures). Afin de mieux comprendre le comportement en vol des ballons, le CNES a mis en place depuis plusieurs années un programme de recherche portant sur l’étude du comportement mécanique de ces structures et des films polymères qui les compose. Il s’est intéressé notamment à l’étude expérimentale et à la modélisation du comportement mécanique en fluage des ballons pressurisés. Plusieurs résultats ont été obtenus permettant de prévoir l’évolution dimensionnelle des ballons suite au phénomène de fluage. En revanche le comportement à la rupture de ces films polymère a été très peu étudié de même que les phénomènes supposés à l’origine de la perte de caractéristiques des films polymères constitutifs des ballons. Les travaux engagés durant cette thèse visent à étudier, quantifier et comprendre les mécanismes d’endommagement amenant la rupture prématurée des ballons. Cet endommagement a deux origines supposées ; d’une part des plis dits simples et triples occasionnés par le stockage, la manipulation et le déploiement des ballons et d’autre part l’endommagement de fluage. / The super-pressure balloons developed by CNES are a great challenge in scientific ballooning. Whatever the balloon type considered (spherical, pumpkin...), it is necessary to have good knowledge of the mechanical behavior of the envelope regarding to the flight level and the lifespan of the balloon. It appears during the working stages of the super pressure balloons that these last can exploded prematurely in the course of the first hours of flight. For this reason CNES and LGP are carrying out research programs about experimentations and modelling in order to predict a good stability of the balloons flight and guarantee a life time in adequacy with the technical requirement. This study deals with multilayered polymeric film damage which induce balloons failure. These experimental and numerical study aims, are a better understanding and predicting of the damage mechanisms bringing the premature explosion of balloons. The following damages phenomena have different origins. The firsts are simple and triple wrinkles owed during the process and the stocking stages of the balloons. The second damage phenomenon is associated to the creep of the polymeric film during the flight of the balloon. The first experimental results we present in this paper, concern the mechanical characterization of three different damage phenomena. The severe damage induced by the wrinkles of the film involves a significant loss of mechanical properties. In a second part the theoretical study, concerns the choice and the development of a non linear viscoelastic coupled damage behavior model in a finite element code.

Orientador: Jaime Frejlich Sochaczewsky / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin / Made available in DSpace on 2018-08-18T12:26:14Z (GMT). No. of bitstreams: 1 Kumamoto_RodrigoEduardoFraga_M.pdf: 7693773 bytes, checksum: 4d2e2c4cc9a1dcef80b69166df4341d2 (MD5) Previous issue date: 2011 / Resumo: Este trabalho apresenta um estudo sobre o efeito de força fotoeletromotriz produzida por um padrão de speckle espacialmente oscilante quando projetado sobre materiais fotocondutores ou fotorrefrativos. Dentre as contribuições desse trabalho podemos citar o aperfeiçoamento tanto do modelo teórico existente quanto do uso desse fenômeno para medida de vibrações mecânicas transversais. Basicamente, o efeito de força fotoeletromotriz gera uma fotocorrente AC com a mesma frequência do padrão oscilante e uma magnitude que depende da amplitude com que o padrão luminoso oscila espacialmente. A partir de nosso modelo teórico foi possível prever a existência de um máximo valor para a fotocorrente, que ocorreria para uma determinada amplitude de vibração relacionada ao tamanho médio do speckle. Con rmamos experimentalmente a existência desse máximo, embora o valor seja um pouco diferente do esperado teoricamente. Medimos a resposta em frequência da fotocorrente e relacionamos os resultados com as respostas temporais características do material fotocondutor. Para realização das medidas experimentais desenvolvemos um sensor de vibração mecânica baseado no efeito de força fotoeletromotriz, demonstrando a aplicabilidade para medidas de amplitude e de frequência de oscilação de uma superfície vibrante. O sensor é constituído por um cristal fotocondutor e por uma eletônica de amplificação. Um laser é direcionado até um alvo vibrante e a luz retroespalhada, na forma de um padrão de speckle, é focalizada sobre o cristal fotorrefrativo, gerando o efeito speckle-foto-fem. Os cristais utilizados foram o Bi12TiO20 e CdTe:V sob iluminação de 532nm e 1064nm, respectivamente. O sistema mostrou ser interessante tanto para a medida de vibrações mecânicas quanto para a caracterização dos materiais usados como sensores / Abstract: This paper presents a study about photoelectromotive force effect produced by a spatially oscillating \ speckle" pattern when projected onto photoconductive or photorefractive materials. Among the contributions of this paper we can mention the improvement of both the existing theoretical model and use this phenomenon to measure the transverse mechanical vibrations. Basically, the effect of photoelectromotive force generates an AC photocurrent with the same frequency of the oscillating pattern and a magnitude which depends on the amplitude to which the light pattern varies spatially. From our theoretical model, we could predict the existence of a maximum value for the photocurrent, which occurs for a given vibration amplitude related to the average size of the \speckle". We con rmed experimentally the existence of this maximum, but the value is a little different than theoretically expected. We measured the frequency response of the photocurrent and related the results with the temporal response characteristics of the photoconductive material. To perform the experimental measurements we developed a mechanical vibration sensor based on photoelectromotive force effect, demonstrating the applicability for measurements of amplitude and frequency of a vibrating surface. The sensor consists of a photoconductive crystal and an electronic amplification. Light from a laser is directed to a target vibrant and the backscattered light in the form of a speckle pattern is focused on the photoconductive crystal. The crystals used were Bi12TiO20 and CdTe:V under illumination of 532nm and 1064nm, respectively. The system is interesting both for mechanical vibrations measurements and for materials characterization / Mestrado / Física da Matéria Condensada / Mestre em Física

Orientador: José Vicente Hallak d'Angelo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química / Made available in DSpace on 2018-08-18T13:13:04Z (GMT). No. of bitstreams: 1 Moreira_CintiaCristinaGarcia_M.pdf: 1646345 bytes, checksum: 6924d108b277ad4e1638c59be0e3def6 (MD5) Previous issue date: 2007 / Resumo: A sutura de categute é um material composto basicamente de colágeno, o qual é uma proteína obtida da camada serosa do intestino delgado de bovinos e é facilmente absorvido pelo corpo humano. Devido a esta característica, fios de categute são muito utilizados em vários tipos de cirurgias, como por exemplo: gastrintestinais, amarraduras de vasos na tela subcutânea, cirurgias ginecológicas e urológicas. De fácil manipulação, a sutura de categute, comporta-se como um corpo estranho, desencadeando uma reação inflamatória intensa ao seu redor. O categute possui uma sólida aceitação no mercado de produtos médicos hospitalares. Seu processo de produção ainda apresenta um alto índice de rejeição (cerca de 25%) do material semi-acabado. Deste percentual rejeitado, mais da metade é devido ao aparecimento de manchas no fio. Esta rejeição se dá, num primeiro momento, exclusivamente em função do aspecto visual, uma vez que fios com manchas são tomados como sendo fios defeituosos. Este trabalho teve por finalidade identificar a influência dos defeitos de manchas no material semi-acabado e também no produto final, comparando o desempenho dos fios com e sem manchas. Nesta comparação entre os fios foram realizados testes visuais (aparência); químicos (teor de cromo e de formol); físicos (resistência à tração com nó, resistência ao encastoamento, diâmetro) e estudos in-vivo (resistência tênsil, reação tissular). Os resultados obtidos demonstraram que os fios manchados possuem um desempenho tão bom quanto os sem mancha e podem ser utilizados sem comprometer a qualidade do produto. Isto possibilitou uma redução significativa das perdas totais no processo, de 25% para 17% de todo o material processado / Abstract: Catgut suture is a material composed basically of collagen which is a fibrous protein obtained from the serosa of bovines intestine and is easily absorbed by the human body. Due this characteristic, catgut sutures can be used in several types of surgeries like: endosurgery, ophthalmology, gynecology and urology. Catgut suture is easy to manipulate, however it can produce an intense inflammatory reaction around it. Catgut is considered a very good product in the market of medical devices. In the catgut raw material process there is a great loss of material (approximately 25%). About half of this rejected material is lost because of the presence of speckles. This rejection is, at first time, because of its visual appearance, once the strands with speckles are considered as a damaged suture. The aim of this work is to study the influence of the presence of speckles in the raw material (semi-finished) as well as in the final product, comparing the performance between the strands with and without speckles. In this comparison the tests performed were: visual (appearance); chemicals (chromium an formaldehyde content); physics (knot tensile strength, needle attachment tensile, diameter); "in-vivo" tests (tensile strength, tissue reaction). The results obtained have shown that it is possible to use the suture with speckles because its performance is as good as the ones without speckle and the quality of the product is not affected by their presence. After this study the total losses in the process were significantly reduced from 25% to 17% of all processed material / Mestrado / Sistemas de Processos Quimicos e Informatica / Mestre em Engenharia Química

Submitted by Nadir Basilio (nadirsb@uninove.br) on 2016-05-19T17:43:26Z No. of bitstreams: 1 Nelson Hideyoshi Koshoji.pdf: 1555158 bytes, checksum: edeadb5cae29044249dc96c8e2bbee65 (MD5) / Made available in DSpace on 2016-05-19T17:43:26Z (GMT). No. of bitstreams: 1 Nelson Hideyoshi Koshoji.pdf: 1555158 bytes, checksum: edeadb5cae29044249dc96c8e2bbee65 (MD5) Previous issue date: 2014-12-01 / Dental erosion is a non-carious cervical lesion that is related to progressive tooth loss through its contact with chemicals that dissolve the enamel hydroxyapatite crystals. Currently, it is a highly prevalent condition among individuals of all ages. The loss of the structure of this tissue causes changes in the roughness of the surface. The objective of this work is to develop a methodology to identify and quantify this injury, in a non-invasively and non-destructive way, with low cost and executed in real time by analyzing the coherent light scattering patterns, called speckle. It was used 32 samples of bovine incisors and they were divided into 4 groups with different times of acid etching. Half of each sample was protected and then immersed in Coke (pH ≅ 2.5) for 10, 20, 30 and 40 min, twice daily and for 7 consecutive days. Each sample has two areas: half healthy and half eroded. After the challenge, the samples were submitted to speckle analysis to find the relative differences between the two regions in each group. It was found 10 min with 18% 20 min with 24% 30 min with 38% and 40 min with 44% of relative difference. After this analysis, we performed also a Knoop hardness test in order to compare methods. There was a linear trend between the methods with coefficient r = 0.80. The speckle image is proportional to the attack time, has a strong correlation and a good agreement with the Knoop hardness test. / A erosão dental é uma lesão cervical não cariosa que está relacionada a perda progressiva do dente através do seu contato com substâncias químicas que dissolvem os cristais de hidroxiapatita do esmalte. Atualmente, é uma condição altamente prevalente entre indivíduos de todas as idades. A perda da estrutura deste tecido provoca alterações na rugosidade de sua superfície. O objetivo deste trabalho é desenvolver uma metodologia que identifique e quantifique essa lesão de forma não invasiva, não destrutiva, com baixo custo e executado em tempo real através da análise dos padrões de espalhamento da luz coerente, denominado speckle. Foram utilizadas 32 amostras de incisivos bovinos e dividida em 4 grupos com diferentes tempos de ataque ácido. Metade de cada amostra foi protegida e, em seguida, imersas em coca-cola (pH ≅ 2,5) durante 10, 20, 30 e 40 min, duas vezes ao dia e 7 dias consecutivos. Cada amostra possui duas áreas: metade saudável e metade erodida. Após o desafio, as amostras foram submetidas à análise speckle para encontrar as diferenças relativas entre as duas regiões de cada grupo. Foi encontrado 10 min com 18%, 20 min com 24%, 30 min com 38% e 40 min com 44% de diferença relativa. Após esta análise, foram realizados, também, o teste de dureza Knoop afim de comparar os métodos. Houve uma tendência linear entre os métodos com coeficiente r = 0.80. A imagem speckle é proporcional ao tempo de ataque, possui uma forte correlação e uma boa concordância com o teste de dureza Knoop.

Submitted by Nadir Basilio (nadirsb@uninove.br) on 2018-06-15T14:04:20Z No. of bitstreams: 1 Silvia Regina Garcia Olivan.pdf: 1038218 bytes, checksum: 76aa261c5a38cecb8a8ea2343053751a (MD5) / Made available in DSpace on 2018-06-15T14:04:20Z (GMT). No. of bitstreams: 1 Silvia Regina Garcia Olivan.pdf: 1038218 bytes, checksum: 76aa261c5a38cecb8a8ea2343053751a (MD5) Previous issue date: 2015-12-16 / The detection of incipient lesions of occlusal caries is a difficult task that requires a rigorous examination is commonly used visual and radiographic inspection. Tooth caries induce the mineral loss, alters the optical properties of the affected tissue, so the study of these properties can produce non-invasive and non-destructive methods for early diagnosis of caries lesions. Thus, the objective of this project is to correlate the results obtained by visual examination by ICDAS and the method by coherent light scattering speckle pattern (statistical patterns of optical granules (speckle) generated by sound and injured dental tissues) . Therefore, we used 30 healthy deciduous molar teeth coming from the Biobank Human Teeth, Faculty of Dentistry, University of São Paulo who had carious lesions induced by pH cycling method. The samples were evaluated for making the diagnosis of caries by two methods: ICDAS and speckle pattern of coherent light scattering in the periods after 5, 10 and 15 days and the results statistically analyzed using α = 0.05 significance level .It was observed a significant difference between the image of the speckle scattering of healthy and injured areas within the 3 study groups, but not when comparing the three groups, showing us that it is an innovative technique that needs further study, but it can be used as a diagnostic method for the detection of early caries lesions. / A detecção de lesões incipientes de cárie oclusal é uma tarefa difícil que requer um rigoroso exame sendo comumente utilizadas a inspeção visual e radiográfica. A cárie dentária por induzir a perda mineral, altera as propriedades ópticas do tecido afetado, assim o estudo dessas propriedades poderá produzir métodos não invasivos e não destrutivos para o precoce diagnóstico de lesões de cárie. Sendo assim, o objetivo desse projeto foi correlacionar os resultados obtidos pelo exame visual através do ICDAS e pelo método por padrão de espalhamento de luz coerente speckle (padrões estatísticos de granulado óptico (speckle) gerado por tecidos dentários sadios e lesionados). Para tanto foram utilizados 30 dentes molares decíduos hígidos oriundos do Biobanco de Dentes Humanos da Faculdade de Odontologia da Universidade de São Paulo que tiveram lesão de cárie induzida pelo método de ciclagem de pH. As amostras foram avaliadas para realização do diagnóstico de cárie por dois métodos: ICDAS e padrão de espalhamento de luz coerente speckle, nos períodos após 5, 10 e 15 dias e os resultados analisados estatisticamente utilizando-se nível de significância de α=0,05. Observou-se que existe diferença significativa entre a imagem do espalhamento speckle das áreas sadias e doentes dentro dos 3 grupos avaliados, mas não quando comparados os 3 grupos, mostrando-nos que é uma técnica inovadora, que necessita de mais estudos, mas que pode ser utilizada como método de diagnóstico para a detecção de lesões de cárie iniciais.

Les nuages, le lait, le papier, les tissus biologiques appartiennent tous à une même classe de milieux que l'on nomme diffusants de part leur habilité à transformer une onde incidente collimatée en un faisceau diffus. L'imagerie, ou le transfert d'information à travers ces milieux est a priori plus difficile qu'en milieu homogène, et les méthodes actuelles nécessitent une caméra en transmission du milieu complexe considéré. La présence de cette caméra est souvent considérée comme une faille de ces méthodes car la transmission de ces milieux est souvent hors d'atteinte par l'opérateur. Dans cette thèse nous posons la question du lien qui existe entre la lumière réfléchie et la lumière transmise en milieux fortement diffusant. Nous traitons ce problème de manière statistique et nous intéressons à la dépendance statistique qui existe entre la lumière réfléchie et la lumière transmise. Nous verrons que ce lien statistique persiste même pour des milieux fortement diffusants. Ce lien statistique peut être a la base de nouvelles méthodes de contrôle du front d'onde en milieux diffusant n'utilisant que des informations réfléchies par le milieu, permettant l'imagerie, le dépôt d'énergie ou d'informations à travers des milieux fortement diffusants. / Clouds, milk, paper or biological tissues are called scattering media for light. Indeed when a plane wave encounters one a these media, the light is scattered and looses its preferential direction. Consequently, imaging through these media is more difficult than in homogeneous media. The existing methods rely on a CCD camera measuring the transmitted light. Nonetheless, the transmitted side of the sample is most of the time out of reach of the operator. In this thesis we interest ourselves to the link that exists between the reflected light and the transmitted light for thick scattering media. From a statistical point of view, this link is equivalent to the statistical dependency between the reflected light and the transmitted light. We show that the statistical dependency persists even for very thick media allowing us to propose new imaging modalities based on it. This statistical dependency between the reflected and the transmitted light is a very rich function of the parameters of the system, and may allow us to control the transmitted light using reflected information only.

Die technologische Entwicklung im Bereich der Echokardiographie hat in der letzten Dekade neue Methoden zur objektiven Erfassung der regionalen linksventrikulären Wandbewegung ermöglicht. Speckle Tracking erfasst die myokardiale Deformation durch die Positionsänderung einzelner Bildpunkte von einem Bild des analysierten Datensatzes zum nächsten. Diese Methode ist dem Gewebedoppler überlegen, insbesondere wegen ihrer Unabhängigkeit vom Anlotungswinkel. Zwei-dimensionale (2D) Speckle Tracking Analysen wurden für die klinische Praxis validiert. Die drei-dimensionale (3D) Echokardiographie erlaubt inzwischen Speckle Tracking Analysen von 3D Datensätzen, welche jedoch für die klinische Praxis noch nicht ausreichend validiert sind. Bei Patienten mit normaler regionaler linksventrikulärer Wandbewegung (N=37), sowie bei Patienten mit ischämie-bedingten Wandbewegungsstörungen (N=18) wurden 3D und 2D Speckle Tracking Analysen durchgeführt. Die Vergleichbarkeit der beiden Methoden hinschtlich der Quantifizierung von normalen und pathologischen Wandbewegungsmustern wurde anhand dieser Messungen geprüft. Des weiteren wurde der Einfluss der Bildrate und Bildqualität drei-dimensionaler Datensätze auf die Vergleichbarkeit beider Methoden analysiert. Es zeigte sich eine gute Vergleichbarkeit des 2D und 3D Speckle Tracking in der Diagnostik eingeschränkter linksventrikulärer systolischer Funktion, sowie in der Lokalisationsdiagnostik umschriebener Wandbewegungsstörungen. 2D und 3D Speckle Tracking sind jedoch noch nicht als gleichwertige Methoden anzusehen. Die Bildqualität, generell bei beiden Modalitäten - jedoch speziell bei 3D Datensätzen, sowie die Bildrate der 3D Datensätze zeigen signifikante Einflüsse auf die 3D Strain Analysen. Eine korrekte Standardisierung der analysierten Aufnahmen und eine optimale Bildqualität sind wichtige Faktoren, die die Zuverlässigkeit des 2D und 3D Speckle Trackings bestimmen.

Orientador: Aparecido Antonio Camacho / Resumo: O objetivo do presente estudo foi investigar a função miocárdica pela técnica de ecocardiografia bidimensional speckle tracking (2D STE) em pacientes submetidos à procedimentos anestésico prolongado, com a intenção de se detectar possível disfunção sistólica. Inicialmente para se determinar o intervalo normal da função sistólica na espécie, foram utilizados 31 coelhos da raça Nova Zelândia, adultos, hígidos, machos, com peso médio de 4,0 ± 0,53 kg, nos quais foram obtidos os índices sistólicos radiais como, velocidade rotacional e radial, deslocamento rotacional e radial, strain radial e strain rate radial. Posteriormente, para investigação da função sistólica sob diferentes modalidades ventilatórias, 32 coelhos foram distribuídos, aleatoriamente, em quatro grupos de modalidades ventilatórias diferentes constituídos de 8 animais cada, denominados grupo ventilação ciclada à pressão (GP), grupo ventilação ciclada à pressão associada à PEEP (GPP), grupo ventilação mandatória intermitente sincronizada (GM) e grupo ventilação espontânea (GE). Em todos os grupos, os parâmetros foram mensurados 40 minutos após a indução anestésica (M0) e reavaliados a cada vinte minutos, durante duas horas ininterruptas (M1, M2, M3 e M4). Portanto, o resultado demonstrados na presente investigação cientifica revelam que nenhuma modalidade ventilatória estudada proporcionou um quadro de disfunção sistólica a luz da técnica 2D STE quando foram comparados em cada momento de avaliação anestésica. / Abstract: The aim of this thesis was to investigate the cardiac function of patients undergoing prolonged anesthesia with the use of a two-dimensional speckle tracking (2D STE) technique to detect systolic dysfunction in order to maintain safety during anesthetic procedure. The study was carried out in healthy rabbits because this species is widely used as a model of experimentation for both humans and other animal species. Initially, the normal range of left ventricular radial systolic function was measured, for this purpose, 31 healthy male adults New Zealand rabbits were used, with average weight of 4.0 ± 0.53 kg, from a specialized producer; radial systolic indices were obtained, such as rotational and radial speed, rotational and radial displacement, radial strain and strain rate. Subsequently, 32 rabbits were randomly assigned to four groups of different ventilatory modalities consisting of 8 animals each, referred to as pressure-cycling ventilation group (GP), pressure-cycling ventilatory group associated with PEEP (GPP), synchronized intermittent mandatory ventilation group (GM) and spontaneous ventilation group (GE). In all groups, the parameters were measured 40 minutes after anesthetic induction (M0) and reevaluated every twenty minutes, for two uninterrupted hours (M1, M2, M3 and M4). Therefore, the results demonstrated in the present scientific investigation reveal that no studied ventilatory modality provided a picture of systolic dysfunction in light of the 2D STE techni... (Complete abstract click electronic access below) / Doutor

No description available.