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Intensidade de pixel e sua correlação com o índice de qualidade óssea de mandíbulas atróficas / Pixel intensity and its correlation with bone quality index of atrophic mandiblesJessica Rabelo Mina Zambrana 20 May 2016 (has links)
O sucesso do tratamento de implantes dentários depende da quantidade e qualidade óssea da área de interesse e o uso da Tomografia Computadorizada por Feixe Cônico (TCFC) pode ser correlacionado para a sua estimativa. O objetivo deste estudo foi avaliar e comparar os níveis de escala de cinza dos voxels de imagens obtidas por TCFC de mandíbulas atróficas com o auxílio de programa para diagnóstico e planejamento de implantes e correlacionar a Intensidade Pixel (IP) com a classificação subjetiva do Índice de Qualidade Óssea (IQO). Foram avaliadas imagens tomográficas de 10 mandíbulas atróficas obtidas do banco de dados do LAPI-FOUSP (Laboratório para Análise e Processamento de Imagens) que receberam 8 marcações em regiões normalmente utilizadas para colocação de implantes (4 em região anterior e 4 em região posterior), sobre estas foram posicionados fios ortodônticos para padronização dos cortes tomográficos e simular posições ideais de implantes. Cortes transaxiais das áreas demarcadas foram obtidas para visualização e análise de 4 regiões corticais e 3 regiões trabeculares do tecido ósseo de cada corte, para a seleção de área foi utilizada a ferramenta Região de Interesse (ROI) de cada programa. As imagens foram analisadas por 3 programas de planejamento Romexis (Planmeca,Finlandia), XoranCAT® (Xoran Technologies, EUA) e OsiriX® (Free Software Foundation, 32 bits, EUA). Os dados foram submetidos a análise estatística de Correlação de Spearman em um nível de significância de 5% (p<0,05), análise de correlação intraclasse intra-observador e inter-observador pelo teste Kappa ponderado e o teste qui-quadrado. Os resultados apresentaram que os programas Romexis e OsiriX apresentaram melhor acuidade para a avaliação subjetiva de qualidade óssea, em contrapartida o programa Xoran apresentou inconsistência de dados. Concluiu-se que há correlação entre Intensidade de Pixel e Qualidade óssea de acordo com os resultados encontrados para os programas OsiriX e Romexis / The success of dental implants treatment depends on the bone quantity and quality of the area of interest and the use of Cone Beam Computed Tomography (CBCT) can be correlated to an estimative. The aim of this study was to evaluate and compare the grey scale levels of voxels obtained by CBCT of atrophic mandibles with the aid of software for diagnosis and planning implants and correlates the Pixel Intensity (PI) with the subjective classification of Bone Quality Index (BQI). Tomographic images of 10 atrofic mandibles obtained from the data base of LAPI-FOUSP (Laboratory of analysis and imaging processing) were evaluated, received 8 marks in areas normally used for implant placement (4 in anterior and 4 in posterior region) on these orthodontic wires were positioned for standardization of tomographic images and simulate optimal implant positions. Transaxial slices of the demarcated areas were made for visualization and analysis of four regions of interest for cancellous bone and three regions of interest for cortical bone and for selection of each area a tool called Region of Interest (ROI) was used by each software. The images were analised by three diferent planning software, Romexis (Planmeca, Finland), XoranCAT® (Xoran Technologies, EUA) e OsiriX® (Free Software Foundation, 32 bits, EUA). Data were subjected to statistical analysis of Spearman correlation, intraclass intra-observer and inter-observer analysis correlation and weighted Kappa concordance coefficient with 5% significance level and chi-squared test; The results presented that Romexis and OsiriX software showed better accuracy for subjective assessment of bone quality, on the other hand Xoran software showed data inconsistency. This study concluded that a correlation was found between Pixel Intensity (PI) and Bone Quality (BQ) due to the results of OsiriX and Romexis software.
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Altas doses de 6-fitase de origem híbrida para frangos de corte de 1 a 41 dias / High doses of 6 phytase of hybrid origin for broilers from 1 to 41 daysAna Paula de Oliveira Saccomani 27 September 2018 (has links)
Objetivou-se elaborar uma revisão sistemática da literatura das exigências de cálcio e fósforo com o uso da enzima fitase em ração para frangos de corte e avaliar altas doses de 6-fitase híbrida em rações, com ajuste na matriz nutricional, sobre o desempenho produtivo, aspectos econômicos, qualidade óssea e características de carcaça de frangos de corte. Para a revisão sistemática adotou-se a metodologia proposta por Lovatto et al. (2007), com a localização de artigos relacionados com o tema, coleta de dados, análise crítica dos artigos, interpretação e representação dos resultados encontrados. Para o desempenho, conduziu-se um experimento com 1200 pintos de um dia, Cobb500®, com peso médio de 47,94 ± 0,54 g, distribuídos em um delineamento em blocos casualizados com cinco tratamentos, com oito repetições de 30 aves cada. Os tratamentos utilizados foram: 1) Controle positivo de acordo com as exigências da Tabela Brasileira para Aves e Suínos; 2) Controle negativo (CN) com redução na matriz nutricional equivalente a dose de fitase de 750 FTU/kg, mas sem a inclusão da enzima; 3) CN com inclusão da fitase em 750 FTU/kg; 4) CN com inclusão da fitase em 1000 FTU/kg; e 5) CN com inclusão da fitase em 1500 FTU/kg. A redução dos nutrientes no controle negativo foi de 0,184% de fósforo disponível, 84,8 kcal/kg de energia metabolizável, 0,36% de proteína bruta, 0,206% de cálcio, 0,002% de sódio, 0,006% de lisina digestível e 0,019% de metionina+cistina digestível. A enzima utilizada foi Natuphos® E 10.000 FTU/g, nova 6-fitase de origem híbrida. Para o desempenho e o rendimento de carcaça foram observadas diferenças entre os tratamentos (p<0,05), sendo que o controle negativo gerou resultados inferiores em relação aos demais tratamentos, enquanto que, para a análise econômica gerou resultados inferiores para as receitas brutas e superiores para os custos de produção (p<0,05). Para a qualidade óssea, a suplementação de fitase nos níveis de 1000 e 1500 FTU/kg geraram resultados semelhantes aos encontrados para o controle o positivo (p<0,05). Dessa maneira, concluiu-se que a suplementação da 6-fitase híbrida em níveis de 1000 e 1500 FTU/kg, com redução de nutrientes na matriz nutricional, melhora o desempenho, as características de carcaça, os aspectos econômicos e os parâmetros de qualidade óssea, conseguindo alcançar a mesma qualidade óssea do controle positivo, porém com um custo reduzido. / The objective of this study was to systematically review the literature on calcium and phosphorus requirements with the use of phytase enzyme in broiler feed and evaluate the levels of hybrid 6-phytase in diets, with an adjustment in the nutritional matrix, on the productive performance, bone quality, and carcass characteristics of broiler chickens. For the systematic review, the methodology proposed by Lovatto et al. (2007), for the localization of articles related to the theme, data collection, critical analysis of the articles, interpretation and representation of the results found. For broilers from 1 to 21 days, the enzyme phytase Natuphos is the most studied and levels above 500 FTU / kg can be used without compromising the performance of the animals, in addition to significantly improving the cost of. An experiment was carried out with 1200 day-old Cobb500® chickens, with a mean weight of 47.94 ± 0.54 g, distributed in a randomized block design with five treatments, with eight replicates of 30 birds each. The treatments used were: 1) Positive control according to the requirements of the Brazilian Poultry and Pork Table; 2) Negative control (CN) with reduction in nutritional matrix equivalent to phytase dose of 750 FTU / kg, but without inclusion of the enzyme; 3) CN with phytase inclusion at 750 FTU / kg; 4) CN with phytase inclusion at 1000 FTU / kg; and 5) CN with phytase inclusion at 1500 FTU / kg. The nutrient reduction in the negative control was 0.184% of available phosphorus, 84.8 kcal / kg of metabolizable energy, 0.36% crude protein, 0.206% calcium, 0.002% sodium, 0.006% digestible lysine and 0.019 % digestible methionine + cystine. The enzyme used was Natuphos® E 10,000 FTU / g, a novel 6-phytase of hybrid origin. For carcass performance and yield, differences between treatments (p <0.05) were observed, and the negative control generated lower results in relation to the other treatments, whereas, for the economic analysis, lower results were obtained for gross and production costs (p <0.05). For bone quality, phytase supplementation at 1000 and 1500 FTU / kg levels were found to be similar to the positive control results (p <0.05). Thus, it is concluded that supplementation of hybrid 6-phytase at levels of 1000 and 1500 FTU / kg, with nutrient reduction in the nutritional matrix, improves performance, carcass characteristics, economic aspects and parameters of bone quality, achieving the same quality bone of the positive control, but with a reduced cost.
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Níveis de cálcio e fósforo disponível para frangos de corte alimentados com dietas contendo doses crescentes de fitase / Reduction of calcium and available phosphorus for broilers fed diets containing increased levels of phytaseRenata Soares Marangoni 05 July 2017 (has links)
Este experimento foi realizado com o objetivo de avaliar a redução dos níveis de cálcio e fósforo disponível em dietas suplementadas com doses crescentes de fitase para frangos de corte. Foram utilizados pintinhos machos da linhagem Cobb (n = 1152) distribuídos em um delineamento inteiramente casualizado em esquema fatorial 3 x4 (três níveis de cálcio e fósforo disponível e quatro níveis de fitase) com 12 tratamentos e oito repetições de 12 aves cada. Os tratamentos experimentais foram: T1 Dieta com níveis de cálcio e fósforo disponível de acordo com o proposto por Rostagno et al. (2011) para as diferentes fases; T2 Dieta com 90% dos níveis de cálcio e fósforo disponível proposto por Rostagno et al. (2011) para as diferentes fases; T3 Dieta com 80% dos níveis cálcio e fósforo disponível proposto por Rostagno et al. (2011) para as diferentes fases; T4 Dieta do T1 + fitase 500 FTU/Kg de ração; T5 Dieta do T2 + fitase 500 FTU/Kg de ração; T6 Dieta do T3 + fitase 500 FTU/Kg de ração; T7 Dieta do T1 + fitase 1.000 FTU/Kg de ração; T8 Dieta do T2 + fitase 1.000 FTU/Kg de ração; T9 Dieta do T3 + fitase 1.000 FTU/Kg de ração; T10 Dieta do T1 + fitase 1.500 FTU/Kg de ração; T11 Dieta do T2 + fitase 1.500 FTU/Kg de ração; T12 Dieta do T3 + fitase 1.500 FTU/Kg de ração. As dietas foram a base de milho e farelo de soja. As aves foram pesadas aos 7, 21 e 42 dias de idade. As características de desempenho foram avaliadas e, aos 42 dias de idade, foram avaliados o rendimento de carcaça e os cortes comerciais. O estudo da qualidade óssea, como a análise da densidade e resistência da tíbia, também foi realizado. Com o aumento das inclusões de fitase houve aumento linear de ganho de peso médio aos 7 dias e aos 21 dias. Da mesma forma, houve redução linear na conversão alimentar aos 21 dias, com o aumento dos níveis de fitase. Considerando o período de 1 a 42 dias, a dieta sem inclusão da enzima apresentou resultados inferiores ao uso das dietas contendo fitase, resultando em um índice de eficiência produtiva com melhores resultados em dietas contendo 500 e 1500 FTU/Kg de ração da enzima. Houve interação entre o nível de cálcio e fosforo na dieta e adição de fitase para os parâmetros de ganho de peso e resistência óssea que neste trabalho foi representada pela força máxima (N). / This trial was conducted with the objective of evaluating the reduction of calcium and phosphorus available for broilers fed diets containing increased levels of phytase. One thousand and one hundred and fifty-two male chicks Cobb-500 (n = 1152) were submitted to a completely randomized factorial 3 x 4 (three levels of calcium and phosphorus available and four levels of phytase and were distributed among 12 treatments and 8 replicates with 12 broilers each replicate. The experimental treatments were: T1 - diet containing calcium and phosphorus availableas proposed by Rostagno et al. (2011) for different phases; T2 diet containing 90% of calcium and phosphoru available in the diet as proposed by Rostagno et al. (2011) for different phases; T3 - diet containing 80% of calcium and available phosphorus in the diet as proposed by Rostagno et al. (2011) for different phases; T4 - T1 Diet + phytase 500 FTU/Kg diet; T5 - T2 Diet + phytase 500 FTU/Kg diet; T6 - T3 Diet + phytase 500 FTU/Kg diet; T7 - T1 Diet + phytase 1.000 FTU/Kg diet; T8 - T2 Diet + phytase 1.000 FTU/Kg diet; T9 - T3 Diet + phytase 1.000 FTU/Kg diet; T10 - T1 Diet + phytase 1.500 FTU/Kg diet; T11 - the T2 diet + phytase 1.500 FTU/Kg diet; T12 - T3 Diet + phytase 1.500 FTU/Kg diet. The diets were corn and soybean meal - based. The broilers were weighed at 7, 21 and 42 days of age. Performance traits s were evaluated and, at 42 days of age. Carcass yield and commercial cuts were also evaluated. Furthermore, a bone quality study, with the analysis of density and tibial resistance, were performed. The increased levels of phytase in the diets determined a linear increased in average weight gain at 7 and 21 days of age. Likewise, the increased levels of phytase in the diets reduced linearly the feed conversion at 21 days of age. Considering the period from day 1 to day 42 the diets without phytase determined inferior results than the diets with phytase inclusion. The better results were found when the diets have between 500 and 1500 FTU of phytase per kg of concentrate. There were an interaction between the calcium and phosphorus levels with phytase concentration for weight gain e bone resistance. In this work, those parameters were represented by the maximum strength (N).
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Defining Bone Quality: Cortical Microdamage and Its Contribution to Fracture Risk in the Human RibDominguez, Victoria Maria 11 September 2018 (has links)
No description available.
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Variation in Cortical Osteocyte Lacunar Density and Distribution: Implications for Bone Quality AssessmentHunter, Randee Linn 14 August 2015 (has links)
No description available.
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The Use of Radiographs, Dual-energy X-ray Absorptiometry, Quantitative Computed Tomography and Micro-computed Tomography to Determine Local Cancellous Bone Quality in the Canine Proximal FemurTownsend, Katy Louise 20 June 2012 (has links)
No description available.
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Roles of limestone particle size ratios and phytase levels on performance, eggshell quality, and bone health in post-peak and late-lay single-cycled W-36 laying hensWaters, Charis 12 May 2023 (has links) (PDF)
The objective of this study was to investigate the role of fine (F) and coarse (C) limestone ratios and exogenous phytase at standard and superdosing activity on performance, egg quality, and bone quality of post-peak and late-lay Hy-Line W-36 hens. For post-peak, treatments with 40F:60C at 0 and 400 FTU/kg (standard phytase activity) increased hen-day egg production (HDEP). Treatments with 15F:85C decreased feed intake (FI) but also increased unsaleable eggs (UE) and eggshell-breaking strength (EBS). Treatments with 0 and 400 FTU/kg increased albumen quality and treatments with 1500 FTU/kg increased bone quality and phytate breakdown. For late-lay, interaction effects of limestone and phytase were observed for FI, HDEP, UE, bone, and egg quality. Treatments with 40F:60C decreased UE and increased EBS and bone mineral content of aluminum (Al). Treatments with 0 FTU/kg increased eggshell proximate of phosphorus (P) and gizzard pH, but 400 and 1500 FTU/kg increased phytate breakdown and bone quality.
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Utilização da tomografia computadorizada de feixe cônico na obtenção dos índices radiomorfométricos em mulheres na pré e pós menopausa / Use of cone beam computed tomography in obtaining radiomorphometric index in women in pre and postmenopausalSalgado, Daniela Miranda Richarte de Andrade 01 July 2016 (has links)
O rastreio de osteoporose utilizando imagens de tomografia computadorizada de feixe cônico (TCFC) é um procedimento ainda discutível. O objetivo deste estudo foi avaliar a qualidade óssea de mulheres de diversas faixas etárias (AG) através de índices de radiomorfométricos obtidos em TCFC. Setenta e cinco imagens de TCFC de mulheres (idades compreendidas entre 40 - 70 anos) foram avaliadas. Os pacientes foram agrupados de acordo com AG, em três maneiras diferentes, de acordo com a prevalência de osteoporose em mulheres brasileiras. Os índices avaliados foram: índice cortical mandibular (ICM), índice mentual (IM) e os índices de tomografia computadorizada superior e inferior (ITC). Dois examinadores calibrados avaliaram as imagens em três tempos: Abertura / reconstrução de imagens (1), repetindo este procedimento e salvando a reconstrução (2), e a avaliação das imagens reconstruídas (3). As reconstruções panorâmicas (variando as espessuras: 0,30, 10, e 20 mm) e imagens transaxiais foram avaliadas. A concordância intra e inter-examinador foram avaliadas por meio do teste Kappa e estatísticas de coeficiente de correlação intraclasse. A correlação de Pearson foi utilizada para verificar a relação entre os índices avaliados e AG. O teste de quiquadrado foi utilizado para comparar a prevalência de osteoporose de acordo com cada parâmetro e AG. Os índices avaliados não apresentaram correlação com AG. Alta concordância intra e inter-examinador foi encontrada para IM e ITC, mas não para ICM. A prevalência da osteoporose variou grandemente, de acordo com o índice avaliado e o valor de corte utilizado para definir a doença (com base na qualidade do osso). Os índices radiomorfométricos quantitativos obtidos na TCFC podem ser avaliados de uma forma reprodutível. Não houve correlação entre os índices e AG, o que sugere que as imagens de TCFC não devem ser utilizadas para o rastreio de osteoporose. / Screening for osteoporosis using cone beam CT images (CBCT) is a datable procedure. The aim of this study was to evaluate the bone quality of women from diverse age groups (AG) using CBCT-based radiomorphometric indices. Seventy-five CBCT images of women (age range 40 - 70) years were evaluated. Patients were grouped according to AG, in three diverse manners, according to prevalence of osteoporosis in Brazilian women. The mandibular cortical (MCI), mental (MI), and the superior and inferior computed tomography (CTI) indices were assessed. Two calibrated examiners assessed the images in three instances: opening/reconstructing the images (1), repeating this procedure (2), and assessing the reconstructed images once again (3). Panoramic reconstructions (0.30, 10, and 20 mm thicknesses) and cross-sectional images were assessed. Intra and inter-examiner agreement were assessed by means of Kappa and intraclass correlation coefficient statistics. Pearson correlation was used to verify the relationship between the assessed indices and AG. Chi-square statistics was used to compare the prevalence of osteoporosis according to each index and AG. Assessed indices showed no correlation with AG. High intraand inter-examiner agreement was found for MI and CTI but not to MCI. The prevalence of osteoporosis varied widely, according to the assessed index and to the cutoff used to define the disease (based on bone quality). Quantitative CBCT-based radiomorphometric indices can be assessed in a reproducible manner. No correlation between AG and the assessed indices was found, suggesting that CBCT images should not be used for the screening of osteoporosis.
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Rôle de l'ostéopontine et de l'ostéocalcine à l'interface organique-inorganique dans les tissus osseux / Role of Osteocalcin and Osteopontin at the Organic-Inorganic Interface in BoneNikel, Ondr̆ej 25 October 2013 (has links)
Avec l'âge, les propriétés mécaniques des os se détériorent, conduisant à un risque accru de fracture. Bien que les mesures de densité minérale osseuse permettent de prédire, dans une certaine mesure, ces risques, elles restent insuffisantes dans un grand nombre de cas. Une compréhension plus complète des différents facteurs permettant de définir la « qualité » d'un os est donc souhaitable. Il est connu que la résistance à la fracture de tissus osseux est affectée non seulement par la glycosylation non-enzymatique du collagène, mais aussi par des protéines non collagéneuses comme l'ostéocalcine (OC) et l'ostéopontine (OPN). Cependant, le rôle structural de ces deux protéines dans l'os est mal connu, de même que la façon dont elles contribuent aux propriétés mécaniques globales. L'objectif de cette thèse est donc de répondre à ces deux points. Un modèle synthétique a ainsi été développé pour élucider quelles sont les interactions-clés gouvernant l'interaction de l'OC et l'OPN avec la phase minérale osseuse. Par ailleurs, en utilisant des os de souris génétiquement modifiées (déficientes en OC et/ou OPN), des études RMN solide ont été menées, pour élucider le rôle de l'OC et l'OPN à l'interface organique-inorganique. Leur lien avec les propriétés mécaniques a aussi été étudié en détail, via des tests de rupture, de fatigue et de fluage. Les résultats obtenus montrent que l'OC et l'OPN ont un rôle structural important dans les tissus osseux, et qu'elles contribuent aux propriétés mécaniques par le biais de leurs interactions ioniques, au niveau des interfaces entre les fibrilles de collagène minéralisés. / The decrease in bone mechanical properties occurs with age. The associated fragility fractures present a global public health concern. The use of bone mineral density as a predictor of risk of fracture is, however, limited. A more comprehensive understanding of bone quality and its link to bone fragility is thus desirable. Besides the brittleness caused by nonenzymatic glycation of collagen, bone fracture resistance is also influenced by noncollagenous components such as osteocalcin (OC) and osteopontin (OPN). The structural role of OC and OPN in bone and how they contribute to mechanical properties is however unclear. The objective of this thesis is to elucidate these two aspects. Key interactions associated with the binding of OC and OPN to bone mineral were studied in a synthetic model. Using genetically modified animal model lacking OC and/or OPN, the role of OC and OPN in organic-inorganic interface was examined by solid state NMR, and their link to mechanical properties was studied via a series of tissue level mechanical tests, measuring fracture toughness, creep, or fatigue. Based on the results obtained, it is concluded that OC and OPN are present as structural elements in bone and contribute to tissue mechanical properties via ionic interactions at the interfaces between mineralized fibrils.
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New algorithms for in vivo characterization of human trabecular bone: development, validation, and applicationsLiu, Yinxiao 01 January 2013 (has links)
Osteoporosis is a common bone disease that increases risk of low-trauma fractures associated with substantial morbidity, mortality, and financial costs. Clinically, osteoporosis is defined by low bone mineral density (BMD). BMD explains approximately 60-70% of the variance in bone strength. The remainder is due to the cumulative and synergistic effects of other factors, including trabecular and cortical bone micro-architecture. In vivo quantitative characterization of trabecular bone (TB) micro-architecture with high accuracy, reproducibility, and sensitivity to bone strength will improve our understanding of bone loss mechanisms and etiologies benefitting osteoporotic diagnostics and treatment monitoring processes.
The overall aim of the Ph.D. research is to design, develop and evaluate new 3-D imaging processing algorithms to characterize the quality of TB micro-architectural in terms of topology, orientation, thickness and spacing, and to move the new technology from investigational research into the clinical arena. Two algorithms regarding to this purpose were developed and validated in detail - (1) star-line-based TB thickness and marrow spacing computation algorithm, and (2) tensor scale (t-scale) based TB topology and orientation computation algorithm.
The TB thickness and marrow spacing algorithm utilizes a star-line tracing technique that effectively accounts for partial voluming effects of in vivo imaging with voxel size comparable to TB thickness and also avoids the problem of digitization associated with conventional algorithms. Accuracy of the method was examined on computer-generated phantom images while the robustness of the method was evaluated on human ankle specimens in terms of stability across a wide range of resolutions, repeat scan reproducibility under in vivo condition, and correlation between thickness values computed at ex vivo and in vivo resolutions. Also, the sensitivity of the method was examined by its ability to predict bone strength of cadaveric specimens. Finally, the method was evaluated in an in vivo human study involving forty healthy young-adult volunteers and ten athletes.
The t-scale based TB topology and orientation computation algorithm provides measures characterizing individual trabeculae on the continuum between perfect plate and perfect rod as well as individual trabecular orientation. Similar to the TB thickness and marrow spacing computation algorithm, accuracy was examined on computer-generated phantoms while robustness of the algorithm across ex vivo and in vivo resolution, repeat scan reproducibility, and the sensitivity to experimental mechanical bone strength were evaluated in a cadaveric ankle study. And the application of the algorithm was evaluated in a human study involving forty healthy young-adult volunteers and ten patients with SSRI treatment.
Beside these two algorithms, an image thresholding algorithm based on the class uncertainty theory is developed to segment TB structure in CT images. Although the algorithm was developed for this specific application, it also works effectively for general 2-D and 3-D images. Moreover, the class uncertainty theory can be utilized as adaptive information in more sophisticated image processing algorithms such as Snakes, ASMs and graph search.
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