Musculoskeletal injuries are the most common injuries sustained by athletes and military recruits and can result in decreased performance and lifelong disability. So common and costly are these injuries that the American Academy of Orthopedic Surgeons has provided guidelines for future research, including recommendations for the development of a large animal model of bone injury (USDA 2001). In human and veterinary medicine, digital radiography represents the primary diagnostic tool the physician uses to diagnose skeletal injury. Advances in digital radiography have provided the veterinarian with opportunities to make both simple and complex radiographic assessments. We investigated a simple quantitative measurement of the solar, concave aspect of the distal phalanx in the horse, termed the Palmar-Metric (PM). The PM was a significant predictor of solar cup volume (p < 0.001) and negatively correlated with age (r2 = 0.28, p < 0.05) as determined from 544 radiographs of the distal phalanx from the left and right front feet. Therefore, veterinarians should be aware of the age related change in the solar, concave aspect of the distal phalanx in the horse. We hypothesized that the decrease in the degree of concavity with age may be due to demineralization and subsequent loss of bone density along the solar margin of the distal phalanx. Therefore, we investigated the quantification of optical bone density (bone OD) via complex radiographic calibration. By developing a brightness/darkness index (BDI), the greyscale of radiographs, calibrated with an aluminum marker of varying known thickness, can be compared to the average density of a cross-section of bone. At varying radiographic exposure intensity (kV) and exposure time (mAs), Al BDI was a significant predictor of bone BDI (r2 = 0.960, p < 0.001) and bone OD (r2 = 0.971, p < 0.001). This method of calibration can be utilized by the radiologist to accurately assess bone OD regardless of technique, and allow direct comparison of radiographs taken under different exposure settings. This method successfully quantifies bone OD via measurement of BDI from standardized digital radiographs, allowing for the opacity of radiographs to be truly comparable when taken under different circumstances.

As complicações peri-implantares, posteriormente a colocação do implante em função, são frequentes e sua identificação precoce pode significar uma terapêutica adequada e consequentemente garantir o sucesso do terapêutica. A proposta neste trabalho foi avaliar longitudinalmente a densidade ótica do osso alveolar peri-implantar na região cervical, analisada, por meio da técnica de subtração radiográfica de um acervo de radiografias digitais adquiridas de pacientes previamente reabilitados com trinta e sete implantes osteointegrados imediatos na região anterior da maxila. Os controles radiográficos foram realizados em cinco momentos: na instalação das próteses, após 15,90,180 e 360 dias, e as radiografias intrabucais foram obtidas pela técnica do paralelismo de cilindro longo, com posicionadores do tipo Hanshin individualizados de forma a garantir a padronização das imagens. As imagens digitais obtidas foram alinhadas e equalizadas e por fim submetidas ao procedimento de subtração radiográfica. Os resultados indicaram que a metodologia de subtração radiográfica é válida para a avaliação da perda óssea peri-implantar, assim como demonstra a literatura. No entanto, a reprodução das angulações verticais e horizontais, apresentam-se como críticas na avaliação da densidade óptica da crista óssea e demandam grande habilidade do operador para a correta aplicação. Por meio dessa técnica, conseguimos avaliar de forma quantitativa e qualitativa as alterações na faces proximais nas imagens radiográficas do acervo analisado. A subtração radiográfica, por meio da ferramenta de histograma, permitiu quantificar de forma objetiva as diferenças encontradas nas análises. / The peri-implant complications, in addition to implant placement in function, are frequent and their early identification could mean a therapy appropriately and consequently guarantee the success of the treatment. The aim of this research was to longitudinally evaluate of the optical density of the peri-implant alveolar bone at the cervical region, analyzed by means of the radiographic subtraction technique, a collection of digital radiographs acquired from patients previously rehabilitated with thirty seven osseointegrated implants. The radiographic controls performed in five moments, at the installation of the prostheses, after 15,90,180 and 360 days, and the intraoral radiographs were obtained by parallelism technique, with Hanshin-type positioners individualized in order to guarantee the standardization of the images. The obtained digital images were aligned and equalized and finally submitted to radiographic subtraction procedure. The results indicated that the methodology of radiographic subtraction is valid for an evaluation of the peri-implant bone loss, as well as to demonstrated at the literature. However, the reproduction of the vertical and horizontal angles, are presented as critical in the evaluation of the optical density, and demand a great ability of the operator for a correct application. Through the technique we obtained a quantitative and qualitative evaluation in the area of proximal images in the radiographic images of the analyzed data. The histogram tool applied on the radiographic subtraction images allowed to quantify objectively as the differences found in the analyzes.

As complicações peri-implantares, posteriormente a colocação do implante em função, são frequentes e sua identificação precoce pode significar uma terapêutica adequada e consequentemente garantir o sucesso do terapêutica. A proposta neste trabalho foi avaliar longitudinalmente a densidade ótica do osso alveolar peri-implantar na região cervical, analisada, por meio da técnica de subtração radiográfica de um acervo de radiografias digitais adquiridas de pacientes previamente reabilitados com trinta e sete implantes osteointegrados imediatos na região anterior da maxila. Os controles radiográficos foram realizados em cinco momentos: na instalação das próteses, após 15,90,180 e 360 dias, e as radiografias intrabucais foram obtidas pela técnica do paralelismo de cilindro longo, com posicionadores do tipo Hanshin individualizados de forma a garantir a padronização das imagens. As imagens digitais obtidas foram alinhadas e equalizadas e por fim submetidas ao procedimento de subtração radiográfica. Os resultados indicaram que a metodologia de subtração radiográfica é válida para a avaliação da perda óssea peri-implantar, assim como demonstra a literatura. No entanto, a reprodução das angulações verticais e horizontais, apresentam-se como críticas na avaliação da densidade óptica da crista óssea e demandam grande habilidade do operador para a correta aplicação. Por meio dessa técnica, conseguimos avaliar de forma quantitativa e qualitativa as alterações na faces proximais nas imagens radiográficas do acervo analisado. A subtração radiográfica, por meio da ferramenta de histograma, permitiu quantificar de forma objetiva as diferenças encontradas nas análises. / The peri-implant complications, in addition to implant placement in function, are frequent and their early identification could mean a therapy appropriately and consequently guarantee the success of the treatment. The aim of this research was to longitudinally evaluate of the optical density of the peri-implant alveolar bone at the cervical region, analyzed by means of the radiographic subtraction technique, a collection of digital radiographs acquired from patients previously rehabilitated with thirty seven osseointegrated implants. The radiographic controls performed in five moments, at the installation of the prostheses, after 15,90,180 and 360 days, and the intraoral radiographs were obtained by parallelism technique, with Hanshin-type positioners individualized in order to guarantee the standardization of the images. The obtained digital images were aligned and equalized and finally submitted to radiographic subtraction procedure. The results indicated that the methodology of radiographic subtraction is valid for an evaluation of the peri-implant bone loss, as well as to demonstrated at the literature. However, the reproduction of the vertical and horizontal angles, are presented as critical in the evaluation of the optical density, and demand a great ability of the operator for a correct application. Through the technique we obtained a quantitative and qualitative evaluation in the area of proximal images in the radiographic images of the analyzed data. The histogram tool applied on the radiographic subtraction images allowed to quantify objectively as the differences found in the analyzes.

One of two project reports. Part B can be found at: / Track-etch imaging is investigated as a recording method for neutron radiographic purposes. A theoretical model is formulated and evaluated together with experimental data which is analyzed in an attempt to explore the possibility of maximizing optical contrast. A central converter system with Lithium-6 as the converter and cellulose-nitrate as the recorders is used. It is found that the maximum contrast is achieved by using a clear cellulose-nitrate recorder at least 10 µm thick and a Lithium-6 converter of approximately 140 µm thickness. / Thesis / Master of Engineering (ME)

Peanut skins have long been a waste product of the peanut industry. The aim of this project was to find suitable applications for this rich source of natural bioactive compounds. Solvent extracts of peanut skins and a multistep solvent extraction process to yield oligiomeric procyanidin (OPC) extracts were found to be inhibitory towards three types of yeasts (Saccharomyces cerevisiae, Zygosaccharomyces bailli, and Zygosaccharomyces bisporus). All extracts were devoid of solvents that may have interfered with the results. The OPC extract exhibited the highest inhibitory effect, and was chosen for fractionation. Fractionation was conducted by means of a silica or size exclusion high performance liquid chromatography (HPLC) column. Fractions were then subjected to a yeast growth curve assay to determine the active fractions. The fractions were then characterized by liquid chromatography-mass spectrometry (LC-MS). Negative mode electrospray MS determined the fractions to contain mostly procyanidins but also proanthocyanidins. Since it is possible for multiple compounds to display the same molecular ion, multistep MS and retention time differences were utilized to tentatively identify the compounds based upon their fragmentation schemes. However, co-elution was prominent, thus specific compounds responsible for yeast growth inhibition could not be determined. The yeast inhibition assay demonstrated that the procyanidin dimers up to tetramers had the best anti-yeast capabilities. / Ph. D.

O IPEN-CNEN/SP produz o combustível para suprir o seu reator nuclear de pesquisas IEA-R1. O combustível é montado a partir de placas combustíveis contendo um núcleo do compósito U3Si2-Al. Uma boa homogeneidade na distribuição de urânio no núcleo da placa combustível é essencial, pois garante um bom desempenho sob irradiação. Considerando a baixa potência do reator IEA-R1, atualmente, a distribuição de urânio na placa combustível é avaliada apenas por meio de inspeção visual de radiografias. Contudo, tendo em vista a possibilidade do IPEN fabricar o combustível para o novo Reator Multipropósito Brasileiro (RMB), que terá potência elevada, tornou-se inadiável o desenvolvimento de uma metodologia para determinar quantitativamente a homogeneidade da distribuição de urânio no combustível. Este trabalho apresenta uma metodologia baseada na atenuação de raios X para quantificar a distribuição da concentração de urânio no núcleo da placa combustível, por meio da análise da densidade óptica de radiografias e comparação com padrões. Os resultados demonstraram a não aplicabilidade do método, considerando a especificação atual para as placas combustíveis, devido ao alto valor do erro intrínseco ao método. Contudo, o estudo dos erros envolvidos na metodologia, buscando aumentar a sua exatidão e precisão, pode viabilizar a aplicação do método para qualificar o produto final. / IPEN/CNEN-SP produces the fuel to supply its nuclear research reactor IEA-R1. The fuel is assembled with fuel plates containing an U3Si2-Al composite meat. A good homogeneity in the uranium distribution inside the fuel plate meat is important from the standpoint of irradiation performance. Considering the lower power of reactor IEA-R1, the uranium distribution in the fuel plate has been evaluated only by visual inspection of radiographs. However, with the possibility of IPEN to manufacture the fuel for the new Brazilian Multipurpose Reactor (RMB), with higher power, it urges to develop a methodology to determine quantitatively the uranium distribution into the fuel. This paper presents a methodology based on X-ray attenuation, in order to quantify the uranium concentration distribution in the meat of the fuel plate by using optical densities in radiographs and comparison with standards. The results demonstrated the inapplicability of the method, considering the current specification for the fuel plates due to the high intrinsic error to the method. However, the study of the errors involved in the methodology, seeking to increase their accuracy and precision, can enable the application of the method to qualify the final product.

O IPEN-CNEN/SP produz o combustível para suprir o seu reator nuclear de pesquisas IEA-R1. O combustível é montado a partir de placas combustíveis contendo um núcleo do compósito U3Si2-Al. Uma boa homogeneidade na distribuição de urânio no núcleo da placa combustível é essencial, pois garante um bom desempenho sob irradiação. Considerando a baixa potência do reator IEA-R1, atualmente, a distribuição de urânio na placa combustível é avaliada apenas por meio de inspeção visual de radiografias. Contudo, tendo em vista a possibilidade do IPEN fabricar o combustível para o novo Reator Multipropósito Brasileiro (RMB), que terá potência elevada, tornou-se inadiável o desenvolvimento de uma metodologia para determinar quantitativamente a homogeneidade da distribuição de urânio no combustível. Este trabalho apresenta uma metodologia baseada na atenuação de raios X para quantificar a distribuição da concentração de urânio no núcleo da placa combustível, por meio da análise da densidade óptica de radiografias e comparação com padrões. Os resultados demonstraram a não aplicabilidade do método, considerando a especificação atual para as placas combustíveis, devido ao alto valor do erro intrínseco ao método. Contudo, o estudo dos erros envolvidos na metodologia, buscando aumentar a sua exatidão e precisão, pode viabilizar a aplicação do método para qualificar o produto final. / IPEN/CNEN-SP produces the fuel to supply its nuclear research reactor IEA-R1. The fuel is assembled with fuel plates containing an U3Si2-Al composite meat. A good homogeneity in the uranium distribution inside the fuel plate meat is important from the standpoint of irradiation performance. Considering the lower power of reactor IEA-R1, the uranium distribution in the fuel plate has been evaluated only by visual inspection of radiographs. However, with the possibility of IPEN to manufacture the fuel for the new Brazilian Multipurpose Reactor (RMB), with higher power, it urges to develop a methodology to determine quantitatively the uranium distribution into the fuel. This paper presents a methodology based on X-ray attenuation, in order to quantify the uranium concentration distribution in the meat of the fuel plate by using optical densities in radiographs and comparison with standards. The results demonstrated the inapplicability of the method, considering the current specification for the fuel plates due to the high intrinsic error to the method. However, the study of the errors involved in the methodology, seeking to increase their accuracy and precision, can enable the application of the method to qualify the final product.

Este trabalho apresenta um método que simula o desempenho dos sistemas de registro radiológicos, considerando tanto a capacidade de absorção, a eficiência de conversão, o espectro de emissão e a eficiência intrínseca do écran quanto a distribuição espacial dos fótons de luz, o ruído quântico, o espectro de sensibilidade do filme, a quantidade de fótons necessários para tomar o grão haleto de prata revelável e um fator que engloba os parâmetros que não são diretamente fornecidos pelos fabricantes. Implementamos os algoritmos empregando o ambiente de programação Delphi, uma ferramenta de desenvolvimento de aplicações para plataforma Windows e microcomputador, que possibilitou o desenvolvimento de uma interface amigável de interação com o usuário. O método prevê a influência de qualquer combinação écran-filme usada ou planejada sobre a nitidez de imagens radiográficas e permite simular o contraste e a nitidez da imagem a ser obtida para uma dada combinação écran-filme em função da exposição quanto a sua curva H&D. / This work presents a method that simulates the performance of radiological recording systems, considering the absorption capacity, the conversion efficiency, the emission spectrum and the intrinsic efficiency of the intensifying screen, the spatial distribution of the light photon, the quantum noise, the sensibility spectrum of the radiographic film, the necessary photons to become the silver halide grain developable and a factor that includes the parameters that are not supplied directly by the manufacturer. We have implemented the algorithms using the Delphi programming language, an application development tool for Windows and personal computer, which allowed the development of a friendly interface of interaction with the user. The method predicts the influence of any screen-film system used or planned on radiographic image sharpness and allows one to simulate the contrast and the image sharpness to be obtained with a given screen-film combination in function of the x-ray exposure as well as the H&D curve this combination.

A multi-wavelength laser diode based optical sensor was designed, developed and evaluated for monitoring and control microalgae growth in real-time. The sensor measures optical density of microalgae suspension at three wavelengths: 650 nm, 685 nm and 780 nm, which are commonly used for estimating microalgae biomass concentration and chlorophyll content. The sensor showed capability of measuring cell concentration up to 1.05 g L⁻¹ without sample dilution or preparation. The performance of the sensor was evaluated using both indoor photobioreactors and outdoor paddle wheel reactors. It was shown that the sensor was capable of monitoring the dynamics of the microalgae culture in real-time with high accuracy and durability. Specific growth rate (μ) and ratios of optical densities (OD ratios) at different wavelengths were calculated and were used as good indicators of the health of microalgae culture. A series of experiments was conducted to evaluate the sensor's capability of detecting environmental disturbances in microalgae systems, for instance, induced by dust or Vampirovibrio chlorellavorus, a bacteria found to cause crash of microalgae culture. Optical densities measured from the sensor were insensitive to the amount of dust that consisted of 59.7% of dry weight of microalgae in the system. However, the sensor was able to detect multiple events of introduction of dust timely by μ and OD ratios. The sensor was also capable of detecting subtle changes of culture in color that leads to a total crash of the culture before it can be differentiated by naked eye. The sensor was further integrated into an existing outdoor raceway to demonstrate the sensor's potential of being a core component to control microalgae production system. A real-time monitoring and control program along with a graphical user interface (GUI) was developed for a central control station aiming at improving resource use efficiency for biomass production.

Este trabalho apresenta um método que simula o desempenho dos sistemas de registro radiológicos, considerando tanto a capacidade de absorção, a eficiência de conversão, o espectro de emissão e a eficiência intrínseca do écran quanto a distribuição espacial dos fótons de luz, o ruído quântico, o espectro de sensibilidade do filme, a quantidade de fótons necessários para tomar o grão haleto de prata revelável e um fator que engloba os parâmetros que não são diretamente fornecidos pelos fabricantes. Implementamos os algoritmos empregando o ambiente de programação Delphi, uma ferramenta de desenvolvimento de aplicações para plataforma Windows e microcomputador, que possibilitou o desenvolvimento de uma interface amigável de interação com o usuário. O método prevê a influência de qualquer combinação écran-filme usada ou planejada sobre a nitidez de imagens radiográficas e permite simular o contraste e a nitidez da imagem a ser obtida para uma dada combinação écran-filme em função da exposição quanto a sua curva H&D. / This work presents a method that simulates the performance of radiological recording systems, considering the absorption capacity, the conversion efficiency, the emission spectrum and the intrinsic efficiency of the intensifying screen, the spatial distribution of the light photon, the quantum noise, the sensibility spectrum of the radiographic film, the necessary photons to become the silver halide grain developable and a factor that includes the parameters that are not supplied directly by the manufacturer. We have implemented the algorithms using the Delphi programming language, an application development tool for Windows and personal computer, which allowed the development of a friendly interface of interaction with the user. The method predicts the influence of any screen-film system used or planned on radiographic image sharpness and allows one to simulate the contrast and the image sharpness to be obtained with a given screen-film combination in function of the x-ray exposure as well as the H&D curve this combination.