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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.
181

Exceptionally Preserved Fossils from Some “Ordinary” Ordovician and Devonian Sedimentary Deposits of the Midwestern United States

Vayda, Prescott James January 2021 (has links)
No description available.
182

Control concepts for image-based structure tracking with ultrafast electron beam X-ray tomography

Windisch, Dominic, Bieberle, Martina, Bieberle, André, Hampel, Uwe 12 August 2020 (has links)
In this paper, a novel approach for tracking moving structures in multiphase flows over larger axial ranges is presented, which at the same time allows imaging the tracked structures and their environment. For this purpose, ultrafast electron beam X-ray computed tomography (UFXCT) is being extended by an image-based position control. Application is scanning and tracking of, for example, bubbles, particles, waves and other features of multiphase flows within vessels and pipes. Therefore, the scanner has to be automatically traversed with the moving structure basing on real-time scanning, image reconstruction and image data processing. In this paper, requirements and different strategies for reliable object tracking in dual image plane imaging mode are discussed. Promising tracking strategies have been numerically implemented and evaluated.
183

Etude expérimentale de l'impact de l'érosion par suffusion sur les propriétés physiques et mécaniques des sols / Experimental investigation of the impact of the erosion by suffusion on the physical and mechanical properties of soils

Nguyen, Cong Doan 06 December 2018 (has links)
Ce travail de thèse s’est attaché à investiguer, d’une part, le mécanisme d’érosion interne par suffusion dans les ouvrages hydrauliques en terre, et d’autre part, les conséquences qu’il pourrait avoir sur le comportement mécanique du sol, l’objectif principal étant d’améliorer notre compréhension de ce processus et du comportement des sols érodés. La démarche adoptée est principalement expérimentale, réalisée à différentes échelles : du macroscopique, à l’échelle du matériau, au microscopique, à l’échelle des grains constitutifs. A l’échelle macroscopique, des essais de suffusion ont été réalisés sur des échantillons de sol à l’aide d’un nouveau dispositif d’essai d’érosion, appelé perméamètre de suffusion, développé dans le cadre de cette thèse. Après érosion dans le perméamètre, les échantillons érodés sont transférés par une procédure de congélation / décongélation dans un dispositif d’essai triaxial afin d’étudier leur comportement sous chargement mécanique. Les résultats obtenus à cette échelle ont permis de donner un aperçu général du mécanisme de suffusion et de mettre en évidence son impact sur les propriétés de résistance au cisaillement du sol. A l’échelle microscopique, une analyse fine a pu être menée en réalisant un essai de suffusion des mesures in-operando de tomographie à rayons X et de la visualisation locale par techniques optiques sur un sol artificiel. La caractérisation du sol à cette échelle microstructurale a permis de mieux comprendre le processus de suffusion, notamment en mettant en évidence l’apparition et le développement de fortes hétérogénéités qui semblent avoir une influence importante sur la réponse mécanique des sols érodés / This thesis work has investigated, on the one hand, the mechanism of internal erosion by suffusion in earthen hydraulic structures, and, on the other hand, the consequences suffusion can cause on the mechanical behavior of soils, the main objective being to improve our understanding of both the suffusion process and the behavior of eroded soils. The approach adopted was mainly experimental, by a multi-scale scope: from macroscopic, at the material scale, to microscopic, at the grain scale. At the macroscopic scale, suffusion experiments were performed on gap-graded cohesionless soil samples using a newly developed testing device, called the suffusion permeameter. Then, the eroded samples are transferred by a freeze/thaw procedure to a triaxial device to study their behavior under mechanical loading. The achieved results provide a general overview of the suffusion mechanism at the sample scale and highlight its impact on soil shear resistance properties. At the microscopic scale, the suffusion mechanism has been studied by performing a suffusion test with in-operando x-ray tomography and using local visualization based on optical techniques in an artificial soil. Subsequent grain-scale analysis has provided a deeper understanding of suffusion process through the characterization of the eroded soil microstructure, particularly highlighting the occurrence and development of strong heterogeneities, which appear to play a key role in the macroscopic mechanical behavior of eroded soils
184

Estimation du volume de glace et imagerie 3D des cryostructures de pergélisol par tomodensitométrie

Darey, Jonas 01 1900 (has links)
Ce mémoire a pour objectif de mieux comprendre la tomodensitométrie par rayons-x appliquée à la géocryologie. La majorité des études ayant pour but d’analyser le pergélisol en utilisant la tomodensitométrie sont qualitative. De ce fait, il est principalement question de décrire les cryostructures et la disposition géométrique de la glace dans le pergélisol. Il existe peu d’études quantitatives où le volume de glace est estimé avec la tomodensitométrie. De ce fait les méthodologies quantitatives sont peu développées et leur degré de confiance est mal connu. Des échantillons de pergélisol ont été scannés puis analysés avec le logiciel de visualisation Dragonfly©. Une méthode d’analyse quantitative a été développée et combinée à des mesures en laboratoire afin de déterminer l’erreur entre la proportion en glace estimée sur les Ct-Scans et celle mesurée sur l’échantillon physique. Ensuite, une équation pour essayer de corriger cette erreur a été appliquée. Celle-ci a été déterminée à partir de comparaisons des estimations des volumes de glace sur les Ct-Scans et leurs valeurs mesurées en laboratoire. Ces comparaisons ont également permis d’estimer la quantité de matière organique présente dans un échantillon. Les cryostructures du pergélisol ont été modélisées en 3D. Cela a permis de bonifier la classification Nord-Américaine établie par Murton et French en 1994 et de quantifier les volumes respectifs de glace et de sédiments. / This thesis aims to better understand x-ray computed tomography in geosciences and more particularly its use with frozen ground science. Most studies in permafrost science using x-ray computed tomography were qualitative. Therefore, they mainly describe the permafrost cryostructures and the geometric arrangement of the ice in permafrost. There were few quantitative studies where the volumetric ice content of permafrost was estimated with Ct-Scans. As a result, quantitative methodologies are poorly developed, and their degree of confidence is also poorly assessed. Samples from different locations in the Canadian Arctic were scanned and analyzed using Dragonfly©, a visualization software. A quantitative analysis method has been developed and combined with laboratory measurements to calculate the error between the proportion of ice estimated on the Ct-Scans and the one measured on the physical sample. A correction method was developed and applied to the Ct-scans dataset to reduce the error in volumetric ice content estimations. This equation also allows to give an estimation of the organic matter proportion inside a sample. The permafrost cryostructures were modeled in 3D. This improved the visualization of the cryostructures of the North American classification established by Murton and French in 1994, and it allowed to quantify their volumetric ice and sediment contents.
185

<strong>Platforms for Molecular Mechanisms and Improvement in Subcutaneous Injection of Biotherapeutics</strong>

Mazin H Hakim (16657281) 03 August 2023 (has links)
<p>Biotherapeutics, such as monoclonal antibodies (mAbs), represent a primary mechanism for treatment of human disease, and there has been a steady increase in Food and Drug Administration approvals since the first one in 1982. Subcutaneous (SC) injection of protein-based therapeutics is a convenient and clinically established drug delivery method that increases the convenience and reduces cost compared to other delivery methods. However, progress is needed to optimize bioavailability via this route. This dissertation describes the methods for evaluation of mass transport of high molecular weight proteins, such as mAbs, following SC injection using <em>in vitro</em> and <em>ex vivo</em> modeling developed to describe the factors relevant for optimal distribution prior to uptake into systemic circulation. The first chapter describes a novel collagen and hyaluronic acid (HA) based hydrogel for investigation of macromolecule transport based on the physiochemical properties of the diffusing molecule and the tissue matrix. This initial study demonstrated that, in collagen alone, collagen combined with HA, and HA alone, the molecules demonstrated different transport paradigms dependent primarily on molecule size, matrix viscosity, and electrostatic charge, respectively. This showed that the local tissue heterogeneity and therapeutic properties could be determining factors for molecule transport and bioavailability. The second, third, and fourth chapters describe two novel platforms for the investigation of injection plume formation in SC tissue utilizing three-dimensional X-ray tomography. Injection plume analysis has been studied comprehensively in the context of insulin transport using co-injection of radiopaque dyes to track the protein distribution. However high molecular weight therapeutics have vastly different physiochemical properties than insulin and are injected under different rates, concentrations, volumes, and viscosities due to dosing considerations. To address the gap mAb distribution, we first developed a novel protein conjugated to an x-ray contrast agent to directly track injection plume formation and investigated the effects of injection rate and tissue location through injections into ex vivo porcine tissue, described in chapters three and four. Ex vivo tissue analysis showed that the rate did not influence the distribution, however, plume volume was lower in porcine belly compared to neck tissue. Whereas porcine tissue is an excellent model to represent the structural features of human injection, the large heterogeneity between animal subjects and collected samples is a disadvantage. Therefore, the fourth chapter describes the fabrication of a gelatin hydrogel-based injection platform representing the dermal and subcutaneous tissue layers for controlled injection plume analysis. In summary, all three models represent useful platforms for the assessment of macromolecular mass transport, pharmaceutical autoinjector performance, as well as the potential impact of tissue properties and intersubject heterogeneity on plume formation. Overall, the findings in these studies might better inform drug designers and clinicians on how to most optimally engineer an injection to deliver the most efficient patient outcomes through better dosing and increased cost savings. </p>
186

Scanning Methods as Monitoring, Verification, and Accounting tools for CO₂ Sequestration in Unconventional Gas Reservoirs

Amante, Joseph David 16 September 2015 (has links)
Unconventional gas reservoirs in carbon dioxide sequestration activities is a relatively new and unexplored concept currently undergoing pilot scale testing. Sequestration has the potential for enhancing gas recovery while mitigating carbon dioxide to long term storage structures. Due to the extremely complex systems associated with these unconventional reservoirs, modeling becomes difficult to predict accurately. This thesis presents methods to increase the confidence of inferred parameter testing for unconventional reservoir sequestration in both seam coal bed methane wells and a shale wells. Various tests include the use of computed tomography coupled with Avizo modeling software, inductively coupled mass spectrometer fluid transport analysis, pressure transient build tests, liquid level detection, and desorption analysis coupled with cleat image analysis. Analyses of coals performed by both environmental scanning electron microscope (ESEM) and micro CT demonstrate that distributions of cleat porosity in coals are anisotropic and not correlated to the seam depth or location. ESEM is used with micro CT scanning to verify the results before and after the impregnation of the carbonic acid. The micro CT data in Avizo Fire© was used calculate an increase in cleat permeability by 25%. The increase of major flow pathways is caused by the dissolution of carbonates. Changes in the structures were observed qualitatively through ESEM and micro CT and quantitatively through Avizo and inductively coupled mass spectrometry. The results of comparative study between the cleat structures and the desorption of various seams indicate a trend in the cleat porosity and the desorption rate of the coals as well as the cleat porosity and the total gas in various seams. / Master of Science
187

Performance and Design of Extruded Fiber-Reinforced Mortar with Preferentially Aligned Fibers

Alarrak, Rashed 03 May 2024 (has links)
This dissertation presents a comprehensive investigation into the mechanical properties of fiber-reinforced concrete (FRC), focusing on fracture and flexural toughness properties, the impact of fiber orientation and distribution, and the evaluation of flexural models for predicting the behavior of functionally graded FRC. It embarks on a critical investigation aimed at bridging a significant gap in the understanding of FRC materials' behavior, particularly in terms of fracture and flexural performance. Across five distinct manuscripts, this work employs a variety of experimental methodologies, including three-point bend tests, four-point bend tests, digital image correlation, X-ray computed tomography, and the implementation of the two parameter fracture model and then size effect fracture method to explore the effects of different casting techniques – namely, conventional casting and pump-driven extrusion – on the performance of FRC. The core hypothesis tested throughout these studies suggests that the extrusion process, by aligning fibers parallel to tensile stresses, significantly enhances the concrete's ductility, post-peak behavior, and overall fracture and flexural properties. This hypothesis was corroborated across various experiments, which demonstrated that fiber alignment via extrusion not only enhances the concrete's mechanical properties but also leads to more effective crack propagation control, increased toughness, and enhanced residual strengths. The research encompasses a series of systematic investigations into the effects of fiber alignment on the mechanical properties of FRC, revealing that the extrusion process significantly enhances fracture and flexural properties and maintains residual strength after peak stress. Utilizing both extrusion-based and conventional casting methods with varying dosages of polyvinyl alcohol fibers, the study demonstrates notable improvements in fracture properties, deflection at failure, and equivalent flexural strength ratio for extrusion-based specimens compared to their conventionally cast counterparts. Moreover, the dissertation explores the impact of casting methods and fiber orientation on fracture energy, offering a size-dependent improvement in extrusion-based methods. The strategic distribution of steel fibers, employing an innovative targeted fiber injection for creating Functionally Graded FRC (FG-FRC), is shown to significantly enhance the structural integrity and resilience of the material. The analysis of flexural models applied to FG-FRC specimens, proposing a novel functionally graded factor to improve model predictability, further advances the understanding of the predictability and reliability of these models in assessing FRC's structural behavior. This dissertation advances academic knowledge in the field of FRC casting and offers significant implications for the construction industry, demonstrating a profound understanding of the challenges and opportunities in extrusion-based FRC casting. Through its innovative approach and detailed investigations, this work contributes significantly to the advancement of the FRC casting field, paving the way for the development of more resilient and efficient construction materials. / Doctor of Philosophy / This research explores the enhancement of concrete's strength and flexibility through the incorporation of individual fibers, with a special focus on the integration and alignment of these fibers. The study examines how concrete can be made more resilient by mixing in fibers in specific ways. A variety of tests, including bending beams and employing advanced imaging techniques, were conducted to observe the effects of mixing fibers using traditional methods versus a novel extrusion-based technique that aligns the fibers in the desired direction in the concrete. The research hypothesized that this innovative alignment method would improve the concrete's ductility and enhance its ability to resist crack propagation. The findings confirmed this hypothesis, revealing that aligned fibers significantly improve concrete's bending capacity, reduce sensitivity to cracking, and retain residual strength even after cracking. Further investigation into varying methods of fiber addition, such as a targeted approach for placing fibers in strategic locations, demonstrated a marked enhancement in the material's ductility. Additionally, the study evaluated mathematical models for predicting the behavior of fiber-reinforced concrete, aiming to improve the understanding and reliability of these models for practical construction applications. In short, the research underscores that adjusting the method of fiber integration into concrete can lead to the development of structures that are both stronger and more durable. This advancement holds promising implications for the future of construction, offering pathways to create more resilient and efficient building materials.
188

Effect of Surface Moisture Condition on Substrate-Repair Concrete Overlay Transition Zone

Annand, Douglas Michael 30 January 2023 (has links)
Concrete is the most widely used construction material in the world. Given its relative availability, strength, economy, and versatility to fit various applications, the material has been incorporated in roadways, bridges, buildings, and a host of other infrastructure projects. Oftentimes, concrete will be exposed to several environmental conditions that ultimately affect its durability and lifespan. These conditions include repeated freezing and thawing, chloride intrusion, sulfate attack, alkali-silica reaction, and many others. Given the age and condition of American infrastructure, concrete structures throughout the country need repair or rehabilitation. Often this repair includes the removal of degraded or damaged concrete and the application of an overlay material. There are several factors affecting the bond performance of the newly formed substrate-repair concrete, such as surface roughness, overlay material, and substrate moisture condition. The work presented in this thesis is dedicated to understanding the effect of substrate moisture condition on the overlay transition zone (OTZ) of the substrate-repair concrete. The substrate moisture condition can significantly impact the microstructure characterization of the OTZ. If the substrate is too dry, then it may absorb water from the repair material, reducing the local water-to-cement (w/c) ratio in the OTZ. Conversely, if the substrate is too wet, then the w/c ratio of the OTZ will be locally increased. In both scenarios, the interfacial bond strength is expected to be modified due to the change in the local w/c ratio. To understand this effect, various test methods and degradation mechanisms were explored. Initially, substrate-repair concrete specimens were prepared utilizing three separate substrate moisture conditions: saturated surfaced dry (SSD), sub-saturated surface dry (Sub-SSD), and oven dry (OD). After allowing these samples to cure, the strength and ion penetration risk were evaluated. The bond strength of the samples was evaluated through flexural strength testing and fracture energy determined through the RILEM draft tests. The OTZ ion penetration risk was evaluated by conducting rapid chloride penetration test (RCPT) on samples prepared with the three substrate moisture conditions. Furthermore, to determine the effect of repeated freezing and thawing on the OTZ and flexural strength, additional samples were created with the three moisture conditions. After allowing these samples to cure, they were subjected to ASTM C666 and were tested to observe their flexural strength. Another important performance indicator of concrete elements is its resistance to chloride ion penetration and corrosion. Since many structural elements are designed with steel reinforcement, chloride ion penetration represents a critical parameter in projecting material performance, since chloride ions will accelerate the rate of steel corrosion. Oftentimes, a key element in projecting this performance is identifying the rate at which ions diffuse through the material. There remain many established techniques to identify this rate of diffusion and derive a chloride diffusion coefficient; however, many of them are either destructive or qualitative in nature. In recent years, transmission X-ray microscopy (TXM) has been employed to non-destructively track diffusion and develop diffusion coefficients. The work presented in this thesis surrounds the efforts of incorporating TXM experiments at Virginia Tech. This work initially utilized a SkyScan 1174 μCT, and additional work in this thesis presents the design and construction of a dental X-ray system based on the checking ion penetration (CHIP) design. This system can conduct TXM experiments utilizing a dental X-ray as the source. The research, design, and construction of the CHIP system is discussed in this thesis. Ultimately, the research in this thesis has not observed any significant relationship between substrate moisture condition and overlay bond strength. There does appear to be an increase in chloride ion resistance for drier substrates, suggesting that pre-wetting the surface increases penetrability of the interface. / Master of Science / Concrete is the most widely used construction material in the world. Given its relative availability, strength, economy, and versatility to fit various applications, the material has been incorporated in roadways, bridges, buildings, and a host of other infrastructure projects. Oftentimes, concrete will be exposed to several environmental conditions that ultimately affect its durability and lifespan. These conditions include repeated freezing and thawing, chloride intrusion, sulfate attack, alkali-silica reaction, and many others. These environmental conditions ultimately degrade the material by inducing cracks, exposing steel reinforcement, and spalling. When the concrete has experienced significant deterioration, repair and rehabilitation of the damaged section must be performed. Most often, this repair consists of the removal of damaged concrete and the application of an overlay material to prevent further deterioration. The topics discussed in this thesis evaluate the optimum substrate conditions prior to an overlay application and the implementation of techniques to evaluate deterioration mechanisms. There are several substrate conditions that will affect bonding with the overlay material, including surface roughness, moisture conditions, and overlay type. This paper focused on the moisture condition and what effect this had on bond strength and resistance to chloride intrusion. This effect was studied in laboratory conditions and under environmental conditions such as rapid freezing and thawing. Several different deterioration mechanisms may contribute to concrete degradation. The research presented in this thesis also aimed to evaluate chloride ion diffusion. To evaluate this mechanism, two systems were explored with the intent of conducting transmission X-ray microscopy (TXM). With TXM, chloride ion diffusion can be tracked to determine the rate at which ions diffuse through the concrete. The two systems explored were an X-ray computed tomography scanner and a dental X-ray system. Both systems can conduct TXM, and this paper presents the efforts dedicated to developing them for this technique at Virginia Tech. Ultimately, the research in this thesis has not observed any significant relationship between substrate moisture condition and overlay bond strength. There does appear to be an increase in chloride ion resistance for drier substrates, suggesting that pre-wetting the surface increases penetrability of the interface.
189

Incorporação e avaliação de novas tecnologias no sistema de serviços de saúde brasileiro: estudo de caso na área de cardiologia / Adoption and asessment of innovative health technologies within the Brazilian health care system: a case study in cardiology

Trindade, Evelinda Marramon 15 August 2006 (has links)
Introdução: Amplo debate tem associado a incorporação de novas tecnologias para a saúde com os custos crescentes dos sistemas de saúde. Face à dúvidas \"se as novas tecnologias são parte do problema, parte da solução ou as duas coisas\" relativamente à saúde da população e do sistema de saúde, este estudo de caso analisa a incorporação de três inovações no Instituto do Coração, InCor-HC/FMUSP, visando elaborar quais fatores influenciaram a decisão de adoção e exemplificar as metodologias de avaliação de novo medicamento, de procedimento diagnóstico e intervenção cirúrgica. A avaliação das tecnologias para a saúde, ATS, pode auxiliar a constituir algumas propostas de respostas. Metodologia: estudo qualitativo empírico em caso retrospectivo de incorporação de três inovações para assistência de alta complexidade em cardiologia. As metodologias utilizadas consistiram em entrevistas aos tomadores de decisão, revisões sistemáticas da literatura relevante, descritiva ou meta-analítica, e análise de impacto econômico hospitalar. Resultados: O padrão do InCor para a incorporação das inovações funciona como um sistema social criativo, sob uma estratégia prática pluralista, ou seja, utilizam as pesquisas, aprovadas pela Comissão de Ética e Pesquisa do InCor e do HC, que se sucederam e que sucedem em incrementos, verificando e ajustando as informações segundo os resultados obtidos para desenhar novas pesquisas. Os atores construíram conhecimentos e negociaram protocolos de pesquisa, promoveram a capacitação de super-especialistas técnicos, transferindo práticas internacionais e gerando conhecimentos adaptados à realidade do Brasil. A avaliação do medicamento tacrolimus demonstra que se poderia resgatar uma média de 75% das rejeições refratárias às terapias convencionais, proporcionando um custo hospitalar de R$ R$ 102,99 por dia de sobrevida nos 8 adultos e R$ 137,53 nas 13 crianças observadas, comparativamente à R$ 229,00 e R$ 260,00, com ciclosporina, respectivamente. Assim, se evitaria 37% da mortalidade associada à episódios de rejeição nos pacientes com transplante cardíaco e, mesmo no único óbito, o custo hospitalar por dia de sobrevida foi de metade que o custo dos períodos observados nos 32 pacientes sob ciclosporina que foram a óbito. O diagnóstico por angiotomocoronariografia em pacientes com angina atípica e risco moderado permitiria orientar o manejo de até dois terços destes casos evitandose coronariografias invasivas. Isto permitiria aumentar a resolutividade do Departamento de Hemodinâmica de 25% para mais 20% dos casos assim estudados, com economias para o InCor, aumento do acesso e resolutividade, podendo evitar até 2.000 mortes, e com o acréscimo estimado de <10% do valor destas 14% mais angioplastias e 6% mais revascularizações cirúrgicas para o SUS. A ablação cirúrgica tem o potencial de curar >10% das fibrilações atriais refratárias a medicamentos em pacientes com indicação de cirurgia aberta para correção de problemas cardíacos estruturais, evitando morbidade e mortalidade em até 1.000 pacientes por ano, se houver suposição que esta seja utilizada apenas com as cirurgias valvares no âmbito do SUS. Conclusões e discussão: As novas tecnologias estudadas proporcionam benefícios à saúde, mas ainda possuem variados graus de incerteza sobre aspectos de segurança e sobre seu potencial de impacto econômico para os programas assistenciais para o InCor e para o SUS. O InCor e os demais hospitais universitários possuem alta capacidade técnica instalada, onde a estruturação de pesquisas facilita e permite a incorporação de inovações de alta complexidade, sem contudo haver planejamento econômico para os programas de assistência à saúde. O isolamento destes atores, em relação às instâncias gestoras do SUS, permite construções sob visões parciais e imediatistas, permite desenvolvimento de interesses externos e diversos, e, por outro lado, pressiona de maneira desordenada a organização e o sistema de saúde. A integração da capacidade profissional, instalada nos hospitais universitários, dentro do circuito de planejamento de médio e longo prazo para o SUS, avaliando as tecnologias inovadoras comparativamente às estabelecidas para a saúde, com base na epidemiologia local observada, pode permitir uma atualização planejada e contínua dos serviços de saúde, construída sobre bases sólidas de conhecimento científico adaptado à nossa realidade e com o responsável equilíbrio orçamentário. / Introduction: There is an ongoing international debate associating the increasing health care costs with adoption of new health technologies. To aid to ascertain whether new health technologies are part of the problem, part of the solution or both in relation to the health of the population and of the health care system, this case study analyses retrospectively three recent decisions to adopt innovations at the Heart Institute, InCor-HC/FMUSP. In order to provide examples of the application of methods for health technologies assessment, the InCor Board of Directors indicated one innovative drug, a new diagnostic procedure and a recent surgery. Methods: Qualitative, retrospective field evaluation of the three decisions for the highest complexity of care in cardiology. Decision-makers survey, systematic reviews (descriptive or meta-analytic) and hospital economic impact analysis were the methodologies applied to this case. Results: A pattern of new technologies incorporation through incremental research, a strategic and pluralist practice emerged within a creative social system. Approved by the InCor and HC Research Ethics Boards and based on previous research results, successive investigations verified and adjusted the informations and generated additional research. Thus, the decision-makers do build knowledge, negotiate research protocols, promote very technical specialists formation and transfer international practice, inter- and up-grading it to the Brazilian reality. Evaluation of these three innovative technologies results are: - The drug tacrolimus may rescue and resolve an average of 75% of the episodes of rejection refractory to conventional medications. The average hospital cost observed (since conversion from CSA, censored at March the 30th, 2006) was of US$45 or R$102.99 per day of survival in 8 adults and of US$61 or R$137.53 for the 13 children (<18 years of age), compared with R$ 229.00 and R$ 260.00, respectively, in those who remained under cyclosporine treatment. Thus, it could prevent 37% rejection related mortality and bring some economy (even in the single child death observed, the hospital cost per day until death was the half of the cost observed for the 32 cyclosporine treated). - The tomoangiocoronariography diagnosis for patients presenting atypical angina and moderate to low risk of stenosis may orient and modify up to 66% clinical decisions preventing requirement of an invasive procedure. This would increase 20% to the Haemodynamic Department 25% resolutivity, may prevent up to 2000 deaths with an estimated additional 10% of the costs of 14% more angioplasties and 6% increase in surgical coronary bypasses for the health care system. - Surgical ablation has the potential to cure more than 10% of medications refractory atrial fibrillation in patients undergoing open heart surgery for structural corrections. Supposing it is restricted only to the group of patients undergoing valve surgery in the health care system, it could prevent morbidity and mortality for up to 1000 patients. Conclusions and discussion: The new technologies evaluated bring benefits to the health of the patients. Safety concerns and economic impact for the InCor and for the health care system assistance programs require further investigation. InCor and the other university hospitals have enhanced technical capacity installed. The structured research facilitates and allows incorporation of highly complex innovations without planning future programs for care. The isolation of these decision makers from the health care system decision planners allows partial views and immediacies. Such a distance facilitates development of external and diverse interests. These facts, consequently, pressures on the organization and the health care system. The integration of the university hospitals installed professional capacities, within an average and long term health care system plans, making evaluations of the innovative health technologies in comparison with the established ones based on local epidemiology, may permit a planned and continuous actualization of the health services on solid scientific basis adapted to the Brazilian reality and with a responsible financial balance.
190

Incorporação e avaliação de novas tecnologias no sistema de serviços de saúde brasileiro: estudo de caso na área de cardiologia / Adoption and asessment of innovative health technologies within the Brazilian health care system: a case study in cardiology

Evelinda Marramon Trindade 15 August 2006 (has links)
Introdução: Amplo debate tem associado a incorporação de novas tecnologias para a saúde com os custos crescentes dos sistemas de saúde. Face à dúvidas \"se as novas tecnologias são parte do problema, parte da solução ou as duas coisas\" relativamente à saúde da população e do sistema de saúde, este estudo de caso analisa a incorporação de três inovações no Instituto do Coração, InCor-HC/FMUSP, visando elaborar quais fatores influenciaram a decisão de adoção e exemplificar as metodologias de avaliação de novo medicamento, de procedimento diagnóstico e intervenção cirúrgica. A avaliação das tecnologias para a saúde, ATS, pode auxiliar a constituir algumas propostas de respostas. Metodologia: estudo qualitativo empírico em caso retrospectivo de incorporação de três inovações para assistência de alta complexidade em cardiologia. As metodologias utilizadas consistiram em entrevistas aos tomadores de decisão, revisões sistemáticas da literatura relevante, descritiva ou meta-analítica, e análise de impacto econômico hospitalar. Resultados: O padrão do InCor para a incorporação das inovações funciona como um sistema social criativo, sob uma estratégia prática pluralista, ou seja, utilizam as pesquisas, aprovadas pela Comissão de Ética e Pesquisa do InCor e do HC, que se sucederam e que sucedem em incrementos, verificando e ajustando as informações segundo os resultados obtidos para desenhar novas pesquisas. Os atores construíram conhecimentos e negociaram protocolos de pesquisa, promoveram a capacitação de super-especialistas técnicos, transferindo práticas internacionais e gerando conhecimentos adaptados à realidade do Brasil. A avaliação do medicamento tacrolimus demonstra que se poderia resgatar uma média de 75% das rejeições refratárias às terapias convencionais, proporcionando um custo hospitalar de R$ R$ 102,99 por dia de sobrevida nos 8 adultos e R$ 137,53 nas 13 crianças observadas, comparativamente à R$ 229,00 e R$ 260,00, com ciclosporina, respectivamente. Assim, se evitaria 37% da mortalidade associada à episódios de rejeição nos pacientes com transplante cardíaco e, mesmo no único óbito, o custo hospitalar por dia de sobrevida foi de metade que o custo dos períodos observados nos 32 pacientes sob ciclosporina que foram a óbito. O diagnóstico por angiotomocoronariografia em pacientes com angina atípica e risco moderado permitiria orientar o manejo de até dois terços destes casos evitandose coronariografias invasivas. Isto permitiria aumentar a resolutividade do Departamento de Hemodinâmica de 25% para mais 20% dos casos assim estudados, com economias para o InCor, aumento do acesso e resolutividade, podendo evitar até 2.000 mortes, e com o acréscimo estimado de <10% do valor destas 14% mais angioplastias e 6% mais revascularizações cirúrgicas para o SUS. A ablação cirúrgica tem o potencial de curar >10% das fibrilações atriais refratárias a medicamentos em pacientes com indicação de cirurgia aberta para correção de problemas cardíacos estruturais, evitando morbidade e mortalidade em até 1.000 pacientes por ano, se houver suposição que esta seja utilizada apenas com as cirurgias valvares no âmbito do SUS. Conclusões e discussão: As novas tecnologias estudadas proporcionam benefícios à saúde, mas ainda possuem variados graus de incerteza sobre aspectos de segurança e sobre seu potencial de impacto econômico para os programas assistenciais para o InCor e para o SUS. O InCor e os demais hospitais universitários possuem alta capacidade técnica instalada, onde a estruturação de pesquisas facilita e permite a incorporação de inovações de alta complexidade, sem contudo haver planejamento econômico para os programas de assistência à saúde. O isolamento destes atores, em relação às instâncias gestoras do SUS, permite construções sob visões parciais e imediatistas, permite desenvolvimento de interesses externos e diversos, e, por outro lado, pressiona de maneira desordenada a organização e o sistema de saúde. A integração da capacidade profissional, instalada nos hospitais universitários, dentro do circuito de planejamento de médio e longo prazo para o SUS, avaliando as tecnologias inovadoras comparativamente às estabelecidas para a saúde, com base na epidemiologia local observada, pode permitir uma atualização planejada e contínua dos serviços de saúde, construída sobre bases sólidas de conhecimento científico adaptado à nossa realidade e com o responsável equilíbrio orçamentário. / Introduction: There is an ongoing international debate associating the increasing health care costs with adoption of new health technologies. To aid to ascertain whether new health technologies are part of the problem, part of the solution or both in relation to the health of the population and of the health care system, this case study analyses retrospectively three recent decisions to adopt innovations at the Heart Institute, InCor-HC/FMUSP. In order to provide examples of the application of methods for health technologies assessment, the InCor Board of Directors indicated one innovative drug, a new diagnostic procedure and a recent surgery. Methods: Qualitative, retrospective field evaluation of the three decisions for the highest complexity of care in cardiology. Decision-makers survey, systematic reviews (descriptive or meta-analytic) and hospital economic impact analysis were the methodologies applied to this case. Results: A pattern of new technologies incorporation through incremental research, a strategic and pluralist practice emerged within a creative social system. Approved by the InCor and HC Research Ethics Boards and based on previous research results, successive investigations verified and adjusted the informations and generated additional research. Thus, the decision-makers do build knowledge, negotiate research protocols, promote very technical specialists formation and transfer international practice, inter- and up-grading it to the Brazilian reality. Evaluation of these three innovative technologies results are: - The drug tacrolimus may rescue and resolve an average of 75% of the episodes of rejection refractory to conventional medications. The average hospital cost observed (since conversion from CSA, censored at March the 30th, 2006) was of US$45 or R$102.99 per day of survival in 8 adults and of US$61 or R$137.53 for the 13 children (<18 years of age), compared with R$ 229.00 and R$ 260.00, respectively, in those who remained under cyclosporine treatment. Thus, it could prevent 37% rejection related mortality and bring some economy (even in the single child death observed, the hospital cost per day until death was the half of the cost observed for the 32 cyclosporine treated). - The tomoangiocoronariography diagnosis for patients presenting atypical angina and moderate to low risk of stenosis may orient and modify up to 66% clinical decisions preventing requirement of an invasive procedure. This would increase 20% to the Haemodynamic Department 25% resolutivity, may prevent up to 2000 deaths with an estimated additional 10% of the costs of 14% more angioplasties and 6% increase in surgical coronary bypasses for the health care system. - Surgical ablation has the potential to cure more than 10% of medications refractory atrial fibrillation in patients undergoing open heart surgery for structural corrections. Supposing it is restricted only to the group of patients undergoing valve surgery in the health care system, it could prevent morbidity and mortality for up to 1000 patients. Conclusions and discussion: The new technologies evaluated bring benefits to the health of the patients. Safety concerns and economic impact for the InCor and for the health care system assistance programs require further investigation. InCor and the other university hospitals have enhanced technical capacity installed. The structured research facilitates and allows incorporation of highly complex innovations without planning future programs for care. The isolation of these decision makers from the health care system decision planners allows partial views and immediacies. Such a distance facilitates development of external and diverse interests. These facts, consequently, pressures on the organization and the health care system. The integration of the university hospitals installed professional capacities, within an average and long term health care system plans, making evaluations of the innovative health technologies in comparison with the established ones based on local epidemiology, may permit a planned and continuous actualization of the health services on solid scientific basis adapted to the Brazilian reality and with a responsible financial balance.

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