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Dimensionamento e monitoramento de defeitos em tubo soldado de aço inoxidável superduplex (UNS S327150) pela técnica de ultrassom phased arrayMoresco, Mauro January 2017 (has links)
A operação segura e eficiente em unidades de produção de petróleo e gás depende do desempenho de seus dispositivos, componentes e estruturas. Dutos rígidos são importantes componentes utilizados na indústria offshore, comumente empregados como flowlines e risers. Durante a vida em serviço destes componentes, eles sofrem tensões axiais cíclicas associadas a sua movimentação, ao processo de extração de petróleo e ao vórtice das marés. O aço inoxidável superduplex surgiu na última década como um material alternativo para ambientes quimicamente agressivos, mas quando catodicamente protegidos contra a corrosão, esses aços são vulneráveis a fragilização por hidrogênio. Este trabalho tem como objetivo, através da técnica de Ensaio Não Destrutivo de ultrassom phased array, monitorar o crescimento de defeitos internos e externos criados intencionalmente próximos à raiz e ao reforço da solda de um tubo de aço superduplex (UNS S32750) de 6´´ submetido a fadiga tração-tração e fragilização induzida por hidrogênio devido à proteção catódica. As inspeções foram realizadas periodicamente com varreduras de 30 a 75° ao longo da circunferência da solda, por um transdutor linear 1-D de 16 elementos e 5MHz acoplado a uma sapata de 36°. Os resultados obtidos foram utilizados para alimentar análises de integridade estrutural, obtenção da curva da/dN x ΔK. / Safe and efficient operation in oil and gas production units depends on the performance of your devices, components and structures. Rigid pipelines are important components in the offshore industry, common used as flowlines and risers. During a life in service of components, they suffer cyclical axial stresses associated with their movement, by the oil extraction process and tidal vortex. Super duplex stainless steel has emerged in the last decade as an alternative material for chemically aggressive environments, but when cathodically protected against corrosion, it is vulnerable to hydrogen embrittlement. This work aims to, through the ultrasonic non-destructive testing by phased array monitor the growth of internal and external defects created intentionally close to the root and reinforcement of the weld of a superduplex steel tube (UNS S32750) with diameter of 6" submitted to tensile-traction fatigue and hydrogen-induced embrittlement due to cathodic protection. The inspections were performed periodically with 30 to 75° scans along the circumference of the weld, by a linear transducer of 1-D, 16-element and 5MHz coupled to a wedge of 36°. The obtained results were used to feed structural integrity analyzes, obtaining the curve of da/dN x ΔK.
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Using Ultrasound as a Pretreatment Method for Ultraviolet Disinfection of WastewatersArmioun, Shaghayegh January 2011 (has links)
In this study, the effects of neutral particles addition on the breakage of wastewater flocs toimprove the efficiency of sonication pretreatment for UV disinfection process have been studied.Kaolin particles as a potentially useful material that is neutral, natural and cheap were added towastewater samples prior to sonication. Results obtained in this study indicated that hard andsmall kaolin particles do not have any significant effect on the particle breakage efficiency byultrasound. The addition of kaolin particles did not significantly increase the cavitation activity(as characterized by potassium iodide actinometry) either. These findings contradict earlierreports that neutral particles can act as nucleation sites and hence enhance cavitation intensity. Inthis work, sonication of wastewater samples for 60s in the absence of kaolin particles resulted inan approximately one log decrease in the number of surviving bacteria colonies at the tailinglevel and 1.4 log units increase at the initial slope of coliform removal in UV dose responsecurve, however addition of kaolin particles prior sonication did not significantly affect the UVdose response curve .The results presented in this study should be treated as preliminary andfurther detailed investigations are needed to better evaluate this issue.
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Estudo anatômico e imaginológico dos órgãos celomáticos do Ramphastos toco - Müller, 1776Silva, Jeana Pereira da January 2019 (has links)
Orientador: Luiz Carlos Vulcano / Resumo: A obtenção de diagnóstico clínico em aves é um desafio, porque geralmente os sinais clínicos são inespecíficos e o exame físico é muito limitado por fatores fisiológicos e anatômicos em comparação aos mamíferos domésticos. Embora os exames de imagem possam ser de grande auxílio no diagnóstico antemortem das aves, justamente por serem métodos rápidos e não invasivos, os aspectos dos órgãos celomáticos nos exames de imagem são pouco valorizados na literatura. Portanto esse estudo teve por objetivo descrever e analisar os aspectos radiográfico, tomográfico e ultrassonográfico das estruturas celomáticas dos Ramphastos toco. Foram analisadas e descritas as imagens da porção final da traqueia, siringe, brônquios, pulmões, coração, proventriculo, ventrículo, alças intestinais, vesícula biliar, fígado, e baço de 15 exemplares de tucanos toco (Ramphastos toco), adultos (machos e fêmeas) e hígidos. Cada uma das técnicas usadas permitiu a avaliação dos órgãos celomáticos, no entanto, alguns exames se mostraram mais eficientes na avaliação de determinados órgãos e sistemas do que os outros. O sistema cardiovascular foi melhor avaliado pelo exame radiográfico. O sistema respiratório inferior foi melhor caracterizado pelo exame tomográfico, e o sistema digestório foi melhor avaliado pelo exame ultrassonográfico. / Abstract: To obtain clinical diagnosis in birds is a challenge because clinical signs are usually non-specific and the physical examination is very limited by physiological and anatomical factors compared to domestic mammals. Although the imaging exams can be of great assistance in the ante-mortem diagnosis of birds, because are fast and non-invasive method, the appearance of the celoma organs in the imaging examinations is little valued in the literature. Therefore, this study aimed to describe and analyze the radiographic, tomographic and ultrasonographic aspects of the celomic structures of the Ramphastos toco. The images of the end portion of the trachea, syrinx, bronchi, lungs, heart, proventriculus, ventricle, intestinal loops, gallbladder, liver, kidneys and cloaca of 15 specimens of toucan toucan (Ramphastos toco), adults (male and female). and healthy. Each of the techniques used allowed evaluation of the celoma organs, however, some tests were more efficient in evaluating certain organs and systems than the others. The cardiovascular system was better evaluated by radiographic examination. The lower respiratory system was better characterized by computed tomography examination, and the digestive system was better evaluated by ultrasonographic examination. / Mestre
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Suivi des structures osseuses par échographie : application à l'arthroplastie totale de la hanche / Ultrasound based femur implant navigation : total hip arthroplastyHaddad, Oussama 21 March 2017 (has links)
L’objectif principal d’une Arthroplastie Totale de Hanche (ATH) est de réduire la douleur en reproduisant les propriétés mécaniques de l’articulation de la hanche à l'aide d'implants artificiels, qui assurent également une fonctionnalité optimale. Ce travail traite de la navigation de l’ATH, à base d’échographie, en mettant l'accent sur la navigation de l'implant fémoral. La conception d'un système de navigation pour l’ATH, basé sur l’échographie peropératoire et CT préopératoire et focalisant sur l’implant fémoral, est proposée. Il fournit un feed back visuel et quantitatif sur l'insertion de l'implant. Le pipeline de navigation proposé inclut : la calibration de la sonde, la segmentation tenant compte de la géométrie d’acquisition, et le recalage profitant de la forme quasi symétrique du fémur. La précision est évaluée en termes cliniques.Les temps d'exécution et la précision obtenus sont encourageants et rendent le pipeline proposé valable pour être évalué en utilisant des données réelles des patients. Une fois notre étude réussie le défi peropératoire, d’autres applications telles que l'arthroplastie totale de l'épaule et l'ablation du cancer osseux peuvent en profiter. / The principal aim of a Total Hip Arthroplasty (THA) is to reduce pain by reproducing the hip joint mechanical properties using artificial implants. This work addresses the ultrasound based navigation of THA, with a focus on the femoral implant. Using a calibrated 3D ultrasound probe, the aim is to image and recognize the femur after implant insertion, then to provide quantitative and visual navigation instructions for optimal implant placement. US bone interfaces are estimated per line of sight, then mapped to CT model profiting from the femur symmetry. The inaccuracy of the proposed navigation system is quantified in clinical terms. The obtained runtimes and accuracies make the proposed pipeline worthy to be tested in the OR. Once the proposed pipeline succeeds the intraoperative challenge, navigated bone tumor ablation and total shoulder arthroplasty can profit from our work.
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Focused Ultrasound Mediated Blood-Brain Barrier Opening in Non-Human Primates: Safety, Efficacy and Drug DeliveryDowns, Matthew January 2015 (has links)
The blood-brain barrier (BBB) is physiologically essential for brain homeostasis. While it protects the brain from noxious agents, it prevents almost all currently available drugs from crossing to the parenchyma. This greatly hinders drug delivery for the treatment of neurological diseases and disorders such as Parkinson’s, Alzheimer’s and Huntington’s, as well as the development of drugs for the treatment of such diseases. Current drug delivery techniques to the brain are either invasive and target specific, or non-invasive with low special specificity. Neither group of techniques are optimal for long term treatment of patients with neurological diseases or disorders. Focused ultrasound coupled with intravenous administration of microbubbles (FUS) has been proven as an effective technique to selectively and noninvasively open the BBB in multiple in vivo models including non-human primates (NHP). Although this technique has promising potential for clinical outpatient procedures, as well as a powerful tool in the lab, the safety and potential neurological effects of this technique need to be further investigated. This thesis focuses on validating the safety and efficacy of using the FUS technique to open the BBB in NHP as well as the ability of the technique to facility drug delivery. First, a longitudinal study of repeatedly applying the FUS technique targeting the basal ganglia region in four NHP was conducted to determine any potential long-term adverse side effects over a duration of 4-20 months. The safety of the technique was evaluated using both MRI as well as behavioral testing. Results demonstrated that repeated application of the FUS technique to the basal ganglia in NHP did not generate permanent side effects, nor did it induce a permanent opening of the BBB in the targeted region. The second study investigated the potential of the FUS technique as a method to deliver drugs, such as a low dose of haloperidol, to the basal ganglia in NHP and mice to elicit pharmacodynamical effects on responses to behavioral tasks. After opening the BBB in the basal ganglia of mice and NHP, a low dose of haloperidol was successfully delivered generating significant changes in their baseline motor responses to behavioral tasks. Domperidone was also successfully delivered to the caudate of NHP after opening the BBB and induced transient hemilateral neglect. In the final section of this thesis, the safety and efficacy of the FUS technique was evaluated in fully alert NHP. The FUS technique was successful in generating BBB opening volumes larger on average to that of the BBB opening volumes in anesthetized experiments. Safety results through MRI verification as well as behavioral testing during application of the technique demonstrated that the FUS technique did not generate adverse neurological effects. Conversely, the FUS technique was found to induce slight positive effects on the response of the NHP to the behavioral task. Collectively, the work presented in this thesis demonstrates the safety and effectiveness of the FUS technique to open the BBB and deliver neuroactive drugs in the NHP.
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Fabrication of Tissue Engineered Osteochondral Allografts for Clinical TranslationNover, Adam Bruce January 2015 (has links)
Damage to articular cartilage, whether through degeneration (i.e. osteoarthritis) or acute injury, is particularly debilitating due to the tissue's limited regenerative capacity. These impairments are common: nearly 27 million Americans suffer from osteoarthritis and 36% of athletes suffer from traumatic cartilage defects. Allografts are the preferred treatment for large cartilage defects, but demand for these tissues outweighs their supply. To generate additional replacement tissues, tissue engineering strategies have been studied as a cell-based alternative therapy.
Our laboratory has had great success repeatedly achieving native or near-native mechanical and biochemical properties in grafts engineered from chondrocyte-seeded agarose hydrogels. The most common iteration of this technique yields a disk of ~4 mm diameter and ~2.3 mm thickness. However, much work is still needed to increase the potential for clinical translation of this product. Our laboratory operates under the premise that in vivo success is predicated on replicating native graft properties in vitro. Compared to these engineered grafts, native grafts are larger in size. They consist of cartilage, which has properties varying in a depth-specific manner, anchored to a porous subchondral bone base. They are able to be stored between harvest and transplantation. This dissertation presents strategies to address a subset of the remaining challenges of reproducing these aspects in engineered grafts.
First, graft macrostructure was addressed by incorporating a porous base to generate biomimetic osteochondral grafts. Previous studies have shown advantages to using porous metals as the bony base. Likewise, we confirmed that osteochondral constructs can be cultured to robust tissue properties using porous titanium bases. The titanium manufacturing method, selective laser melting, offers precise control, allowing for tailoring of base shape and pore geometry for optimal cartilage growth and osteointegration. In addition to viability studies, we investigated the influence of the porous base on the measured mechanical properties of the construct's gel region. Through measurements and correlation analysis, we linked a decrease in measured mechanical properties to pore area. We promote characterization of such parameters as an important consideration for the generation of functional grafts using any porous base.
Next, we investigated a high intensity focused ultrasound (HIFU) denaturation of gel-incorporated albumin as a strategy for inducing local tissue property changes in constructs during in vitro growth. HIFU is a low cost, non-contact, non-invasive ultrasound modality that is used clinically and in the laboratory for such applications as ablation of uterine fibroids and soft tissue tumors. Denaturing such proteins has been shown to increase local stiffness. We displayed the ability incorporate albumin into tissue engineering relevant hydrogels, alter transport properties, and visualize treatment with its denaturation. HIFU treatment is aided by the porous metal base, allowing for augmented heating. Though heating cartilage is used in the clinic, it is associated with cell death. We investigated this effect, finding that the associated loss of viability remains localized to the treatment zone over time. This promotes the option of balancing desired changes in tissue properties against the concomitant cell viability loss.
In order to match clinically utilized allografts, engineered constructs must be scaled up in size. This process is limited by diffusional transport of nutrients and other chemical factors, leading to preferential extracellular matrix deposition in the construct periphery. Many methods are being investigated for overcoming this limitation in fixed-size constructs. In this chapter, we investigated a novel strategy in which small constructs are cultured for future assembly. This modular assembly offers coverage of variable sized defects with more consistent growth with more uniform distribution of biochemical constituents than large constructs cultured on their own. Physiologic failure testing showed that integration of these tissues may be strengthened by increased subunit strength or assembled culture. It is expected that bioadhesive caulking and/or the incorporation of osteochondral bases would further increase integration of the assembled large graft.
Finally, we sought to provide a preservation/storage protocol for engineered cartilage constructs. Such a technique is critical for clinical translation, providing the engineered graft with a “shelf-life.” We adopted and evaluated the Missouri Osteochondral Allograft Preservation System (MOPS), which had been shown to maintain cell viability in native grafts for at least 63 days at room temperature without serum or growth factors. Within the current clinical of 28 days, MOPS maintained chondrocyte viability and 75% of the pre-preservation Young's modulus without significant decline in biochemical content, however it did not extend the clinical window as it had with native grafts. Refrigeration with MOPS did not show any benefit at day 28, but proved better with longer preservation times. These results are the first evaluating engineered cartilage storage. Further optimization is necessary to extend storage tissue property maintenance in storage.
Overall, this dissertation presents four strategies for increasing the translation potential of engineered articular cartilage grafts by better matching the clinically utilized native allograft system. Combining these techniques, one could ideally engineer small, interlocking ostechondral constructs with HIFU modified interface properties, which could be stored from maturity to implantation. Future optimization is required to better understand and utilize these methods to engineer fully functional, clinically relevant grafts.
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Correlações da biometria ultrassonográfica testicular com medidas prostáticas e corporais em cães / Correlations of testicular ultrasound biometry with prostatic and body measurements in dogsGonçalves, Denise 15 December 2015 (has links)
Foram realizadas as biometrias ultrassonográficas testiculares e prostáticas, e mensurações corporais como altura de cernelha, comprimento do corpo, estatura e peso corporal de 54 cães inteiros, com idade entre 24 e 50 meses e escore corporal definido eliminando animais obesos. As medidas testiculares apresentaram correlação positiva forte com as medidas prostática, medidas corporais e peso metabólico (p<0,001), e correlação positiva moderada com o índice de massa corporal canino (IMCC). Foi possível determinar um intervalo de confiança entre as medidas testiculares e prostáticas no grupo de animais estudados e elaborar equações lineares simples para se estimar as medidas prostáticas a partir das medidas testiculares. Definiu-se equações utilizando o comprimento testicular (CT) ou o diâmetro testicular (DT) em centímetros. Comprimento próstata = CT x 0,82 (r2 = 0,97); Comprimento da próstata = DT x 1,27; Altura próstata = CT x 0,72 (r2 = 0,97); Altura da próstata = DT x 1,12; Largura próstata = CT x 0,85 (r2 = 0,96); Largura da próstata = DT x 1,32. Não houve diferença estatisticamente significativa entre as dimensões de comprimento e diâmetro dos testículos direito e esquerdo / The ultrasound biometry of testicular and prostate as well as body measurements such as withers height, body length, height and weight were done of 54 dogs, aged between 24 and 50 months and body condition defined eliminating obese animals. The testicular measurements showed strong positive correlation with prostate size and body measurements as well as with metabolic weight (p < 0,001), and moderate positive correlation with de canine body mass index (IMCC). It was possible to determine a confidence interval between testicular and prostate measures. Simple linear equations to estimate prostate measures from the testicular measures were done. The equations was defined using testicular length or testicular diameter in centimeters. Prostate length = testicular length x 0,82 (r2 = 0,97); Prostate length = testicular diameter x 1,27; Prostate height = testicular length x 0,72 (r2 = 0,97); Prostate length = testicular diameter x 1,12; Prostate width = testicular length x 0,85 (r2 = 0,96); Prostate widht = testicular diameter x 1,32. There was no statistically significant difference between the dimensions of the right and left testicles
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Imagens acústicas geradas pela interação da radiação ultrassônica com o meio material / Acoustic images generated by the interaction of ul-trasonic radiation with the medium.Baggio, André Luis 16 September 2011 (has links)
Neste trabalho é apresentada uma nova modalidade de imagens elastográficas baseada na emissão acústica, quando um meio é submetido à radiação ultrassônica. Esta técnica está sendo denominada de Acustografia por Pulso/Emissão (APE). Características não-lineares da propagação acústica de ondas ultrassônicas, e a resposta mecânica vibracional, foram utilizadas como artifício para geração de imagens com frequências da ordem de quilohertz (kHz), a partir da excitação com ondas ultrassônicas na ordem de megahertz. Para produzir imagens com essa nova modalidade, simuladores de tecido biológicos foram construídos com diferenças de rigidez localizadas, e submetidos a uma radiação ultrassônica focalizada (MHz). O som emitido devido a interação da onda ultrassônica com a região de interesse era gravado e processado de modo a associar a cada pequena porção do tecido a um valor relacionado a rigidez para a formação da imagem. Os resultados mostraram que o método pode produzir imagens associadas às alterações viscoelásticas das amostras. A resolução espacial mostrou-se fortemente ligada a morfologia do campo acústico de excitação, sendo possível detectar estruturas da ordem de 0,25 mm isoladamente. A técnica de aquisição, desenvolvida e apresentada neste trabalho, é similar a técnica de vibroacustografia todavia, com uma instrumentação reduzida e com a possibilidade de obtenção de mais informações da estrutura do meio material, a partir dos fenômenos não lineares observados. Estudos pilotos de aplicação desta nova técnica e com a vibroacustografia, foram realizados e comparados para a avaliação de potenciais aplicações, por exemplo, na avaliação do sinal acústico diante de mudanças nas propriedades viscoelásticas do meio induzidas por mudança de temperatura; formação de imagens em meios com inclusões isoecogênicas e com rigidez ligeiramente diferentes; geração de imagens de estrutura óssea in vitro. / In this work is presented a new modality of elastography images based on the acoustic emission when a material medium was subjected to a ultrasound radiation.This tecnique Nonlinearity behavior of the acoustic wave propagation and the vibrational mechanical response were used to produce images from kilohertz frequencies when the sample was excited by ultrasound waves in megahertz. To produce images with this modality, tissue mimicking phantoms were made with stiffness in homogeneities and subjected a focused ultrasound radiation pulses. The sound emitted due the interaction of the ultrasound wave with the region of interest was recorded and processed in order to associate each small portion of the tissue to a value for image formation. The results showed that this method can produce images associated to the viscoelastic changes of the samples. The spatial resolution have showed strongly linked to the morphology of the excitation acoustic field, this way was possible to detect isolated structures in order of 0.25 mm. The acquisiton technique developed and presented in this work is similar to the vibroacoustography technique, however with reduced instrumentation setup and with the possibility to acquire further information about the structure of the material from the nonlinear phenomenal. Preliminary studies of this new technique and the vibroacoustography were made and compared to evaluate the potential applications, for example, in the evalution of the acoustic signal behavior due changes in the viscoelastic properties changes induced by temperature variations; image formation in the medium with lightly stiffness inclusions; generation of the images of bone structure in vitro.
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Efeito da hipertensão arterial na atuação da musculatura do sistema estomatognático - avaliação eletromiográfica, espessura muscular, força de mordida e eficiência mastigatória / Effect of hypertension on the action of the muscles of the stomatognathic system - electromyographic evaluation, muscle thickness, bite force and masticatory efficiencyLellis, João Batista Mattos 13 December 2013 (has links)
Hipertensão arterial sistêmica é uma condição clínica multifatorial caracterizada por níveis elevados e sustentados de pressão arterial (PA), associada com alterações funcionais e/ou estruturais dos órgãos e a alterações metabólicas. A prevalência da hipertensão no Brasil aponta um índice acima de 30%, sendo considerado um problema de saúde pública. O objetivo desse trabalho foi avaliar o sistema estomatognático de indivíduos hipertensos medicados e controlados, comparando a um grupo controle por meio de análises eletromiográficas, espessura dos músculos masseter e temporal e a força de mordida molar máxima. Os dados foram tabulados e comparados pelo teste t (SPSS 19.0). Verificou-se que os indivíduos hipertensos apresentaram maior atividade eletromiográfica nas condições clínicas posturais da mandíbula, menor espessura muscular dos temporais e maior força de mordida molar máxima direita e esquerda (p<0,05). Baseado nos resultados dessa pesquisa pode-se concluir que a doença hipertensão promoveu alterações funcionais do sistema mastigatório. / Hypertension is a multifactorial clinical condition characterized by high and sustained levels of blood pressure, associated with functional and / or structural organs and metabolic changes. The prevalence of hypertension in Brazil points an index above 30 % and this disease is considered a public health problem. The aim of this study was to evaluate the stomatognathic system in treated and controlled hypertensive individuals, compared to a control group using electromyographic analyzes, masseter and temporal thickness and maximum molar bite force. Data were tabulated and compared by t test (SPSS 19.0). It was found that individuals with hypertension had higher EMG activity in clinical conditions mandible posture, lower thickness of the temporal muscle and greater molar bite force maximum, right and left side (p< 0.05). Based on the results of this research can be concluded that the disease hypertension promoted functional changes of the masticatory system.
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Reconstrução tri-dimensional de imagens obstétricas de ultra-som utilizando linguagem computacional Java e OpenGL / Reconstruction three-dimensional of obstetritics images of ultrasound using computational language JAVA and OpenGLGoes, Claudio Eduardo 15 June 2007 (has links)
Este projeto de pesquisa trata da elaboração de um sistema de reconstrução de imagens obstétricas de fetos, em aparelhos de ultra-som convencionais, para a visualização dessas imagens em três dimensões utilizando a internet como meio de utilização do sistema, com o principal objetivo de proporcionar aos médicos ginecologistas melhor visualização do formato e das estruturas internas, e em especial da face do feto, através do processo de reconstrução tridimensional feito a partir de um conjunto de imagens bidimensionais capturadas em aparelhos convencionais de ultra-som. O uso clínico deste projeto está previsto para o setor de obstetrícia do Hospital das Clínicas de Ribeirão Preto. / This project of research deals with the laboration of a reconstruction system of obstetrics images of embryos in devices of ultrasound will be conventional the visualization of these images in three dimensions using the internet half of uses of the system, with the main objective provides to the medical gynecologists a better visualization of the format and the internal structures and in special the face of the embryo through the made process of three-dimensional reconstruction from a dataset of captured bi-dimensional images in conventional devices of ultrasound. The clinical uses of this project is foreseen will be the sector of obstetrics of the Hospital of the Clinics of Ribeirão Preto.
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