974 resultados para SEGREGATED ANATOMICAL INPUTS


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One of the current frontiers in the clinical management of Pectus Excavatum (PE) patients is the prediction of the surgical outcome prior to the intervention. This can be done through computerized simulation of the Nuss procedure, which requires an anatomically correct representation of the costal cartilage. To this end, we take advantage of the costal cartilage tubular structure to detect it through multi-scale vesselness filtering. This information is then used in an interactive 2D initialization procedure which uses anatomical maximum intensity projections of 3D vesselness feature images to efficiently initialize the 3D segmentation process. We identify the cartilage tissue centerlines in these projected 2D images using a livewire approach. We finally refine the 3D cartilage surface through region-based sparse field level-sets. We have tested the proposed algorithm in 6 noncontrast CT datasets from PE patients. A good segmentation performance was found against reference manual contouring, with an average Dice coefficient of 0.75±0.04 and an average mean surface distance of 1.69±0.30mm. The proposed method requires roughly 1 minute for the interactive initialization step, which can positively contribute to an extended use of this tool in clinical practice, since current manual delineation of the costal cartilage can take up to an hour.

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Background: Kidney stone is a major universal health problem, affecting 10% of the population worldwide. Percutaneous nephrolithotomy is a first-line and established procedure for disintegration and removal of renal stones. Its surgical success depends on the precise needle puncture of renal calyces, which remains the most challenging task for surgeons. This work describes and tests a new ultrasound based system to alert the surgeon when undesirable anatomical structures are in between the puncture path defined through a tracked needle. Methods: Two circular ultrasound transducers were built with a single 3.3-MHz piezoelectric ceramic PZT SN8, 25.4 mm of radius and resin-epoxy matching and backing layers. One matching layer was designed with a concave curvature to work as an acoustic lens with long focusing. The A-scan signals were filtered and processed to automatically detect reflected echoes. Results: The transducers were mapped in water tank and tested in a study involving 45 phantoms. Each phantom mimics different needle insertion trajectories with a percutaneous path length between 80 and 150 mm. Results showed that the beam cross-sectional area oscillates around the ceramics radius and it was possible to automatically detect echo signals in phantoms with length higher than 80 mm. Conclusions: This new solution may alert the surgeon about anatomical tissues changes during needle insertion, which may decrease the need of X-Ray radiation exposure and ultrasound image evaluation during percutaneous puncture.

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Background: An accurate percutaneous puncture is essential for disintegration and removal of renal stones. Although this procedure has proven to be safe, some organs surrounding the renal target might be accidentally perforated. This work describes a new intraoperative framework where tracked surgical tools are superimposed within 4D ultrasound imaging for security assessment of the percutaneous puncture trajectory (PPT). Methods: A PPT is first generated from the skin puncture site towards an anatomical target, using the information retrieved by electromagnetic motion tracking sensors coupled to surgical tools. Then, 2D ultrasound images acquired with a tracked probe are used to reconstruct a 4D ultrasound around the PPT under GPU processing. Volume hole-filling was performed in different processing time intervals by a tri-linear interpolation method. At spaced time intervals, the volume of the anatomical structures was segmented to ascertain if any vital structure is in between PPT and might compromise the surgical success. To enhance the volume visualization of the reconstructed structures, different render transfer functions were used. Results: Real-time US volume reconstruction and rendering with more than 25 frames/s was only possible when rendering only three orthogonal slice views. When using the whole reconstructed volume one achieved 8-15 frames/s. 3 frames/s were reached when one introduce the segmentation and detection if some structure intersected the PPT. Conclusions: The proposed framework creates a virtual and intuitive platform that can be used to identify and validate a PPT to safely and accurately perform the puncture in percutaneous nephrolithotomy.

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Este artigo analisa a eficiência dos gastos públicos nos municípios fluminenses no período 1999/2000, por meio da aplicação da análise envoltória de dados. O estudo adota os indicadores sociais e de gastos municipais das seguintes áreas temáticas da realidade social: educação e cultura; saúde e saneamento. O artigo apresenta uma revisão de várias aplicações de DEA no campo das políticas públicas e, em seguida, os indicadores e modelos propostos para análise da eficiência dos gastos sociais. Aplicou-se o modelo BCC da DEA, com orientação output, isto é, visando maximizar os outputs sem diminuir os inputs. Foram selecionados indicadores de despesas per capita com educação e cultura e com saúde e saneamento como inputs do modelo em questão. Já as variáveis "candidatas" a outputs foram definidas como: taxa de alfabetização de 10 a 14 anos; proporção de domicílios particulares permanentes com esgotamento sanitário adequado; proporção de domicílios particulares permanentes com saneamento adequado; o inverso da taxa de mortalidade por causas hídricas; a proporção de crianças de dois a cinco anos matriculadas em creches ou escolas de educação infantil. O artigo destaca como "boas práticas", no que se refere à eficiência das políticas públicas, pelos resultados que alcançam em termos do que alocam como recursos ou pelas condições de renda média, os municípios de São Gonçalo, Japeri, Queimados, Cantagalo, São João de Meriti e Resende.

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The majority of worldwide structures use concrete as its main material. This happens because concrete is economically feasible, due to its undemanding production technology and case Of use. However, it is widely recognized that concrete production has a strong environmental impact in the planet. Natural aggregates use is one of the most important problems of concrete production nowadays, since they are obtained from limited, and in some countries scarce, resources. In Portugal, although there are enough stone quarries to cover coarse aggregates needs for several more years, Supplies of fine aggregates are becoming scarcer, especially in the northern part of the country. On the other hand, as concrete structures' life cycle comes to an end, an urgent need emerges to establish technically and economically viable solutions for demolition debris, other than for use as road base and quarry fill. This paper presents a partial life cycle assessment (LCA) of concrete made with fine recycled concrete aggregates performed with EcoConcrete tool. EcoConcrete is a tailor-made, interactive, learning and communications tool promoted by the Joint Project Group (JPG) on the LCA of concrete, to qualify and quantify the overall environment impact of concrete products. It consists of an interactive Excel-spreadsheet in which several environmental inputs (material quantities, distances from origin to production Site, production processes) and outputs (material, energy, emissions to air, water, soil or waste) are collected in a life cycle inventory, and are then processed to determine the environmental impact (assessment) of the analysed concrete, in terms of ozone layer depletion, smog or "greenhouse" effect.

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INTRODUÇÃO: Os dados apresentados fazem parte de um estudo multicêntrico sobre automedicação na América Latina realizado pela Organização Mundial de Saúde (OMS). Objetivou-se traçar um perfil da automedicação através da análise da procura de medicamentos em farmácias sem prescrição médica ou aconselhamento do farmacêutico/balconista. MATERIAL E MÉTODO: As especialidades farmacêuticas foram classificadas pelo código "Anatomical Therapeutical Classification" e analisadas sob quatro aspectos qualitativos: valor intrínseco, essencialidade (lista da OMS e Relação Nacional de Medicamentos Essenciais (RENAME), combinação em dose fixa e necessidade de prescrição médica. RESULTADOS: Foram solicitadas 5.332 especialidades farmacêuticas (785 diferentes princípios ativos), sendo 49,5% combinações em dose fixas, 53,0% de valor intrínseco não elevado, 44,1% sujeitos a prescrição médica, 71,0% não essenciais e 40,0% baseados em prescrições médicas anteriores. Os medicamentos mais solicitados foram analgésicos (17,3%), descongestionantes nasais (7,0%), antiinflamatório/antireumático e antiinfecciosos de uso sistêmico, ambos com 5,6%. CONCLUSÕES: Os dados sugerem que a automedicação no Brasil reflete as carências e hábitos da população, é consideravelmente influenciada pela prescrição médica e tem a sua qualidade prejudicada pela baixa seletividade do mercado farmacêutico.

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It is proposed a new approach based on a methodology, assisted by a tool, to create new products in the automobile industry based on previous defined processes and experiences inspired on a set of best practices or principles: it is based on high-level models or specifications; it is component-based architecture centric; it is based on generative programming techniques. This approach follows in essence the MDA (Model Driven Architecture) philosophy with some specific characteristics. We propose a repository that keeps related information, such as models, applications, design information, generated artifacts and even information concerning the development process itself (e.g., generation steps, tests and integration milestones). Generically, this methodology receives the users' requirements to a new product (e.g., functional, non-functional, product specification) as its main inputs and produces a set of artifacts (e.g., design parts, process validation output) as its main output, that will be integrated in the engineer design tool (e.g. CAD system) facilitating the work.

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Mestrado em Segurança e Higiene no TRabalho.

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Mestrado em Radiações Aplicadas às Tecnologias da Saúde. Área de especialização: Protecção Contra Radiações

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Once in a digital form, a radiographic image may be processed in several ways in order to turn the visualization an act of improved diagnostic value. Practitioners should be aware that, depending on each clinical context, digital image processing techniques are available to help to unveil visual information that is, in fact, carried by the bare digital radiograph and may be otherwise neglected. The range of visual enhancement procedures includes simple techniques that deal with the usual brightness and contrast manipulation up to much more elaborate multi-scale processing that provides customized control over the emphasis given to the relevant finer anatomical details. This chapter is intended to give the reader a practical understanding of image enhancement techniques that might be helpful to improve the visual quality of the digital radiographs and thus to contribute to a more reliable and assertive reporting.

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Metalearning is a subfield of machine learning with special pro-pensity for dynamic and complex environments, from which it is difficult to extract predictable knowledge. The field of study of this work is the electricity market, which due to the restructuring that recently took place, became an especially complex and unpredictable environment, involving a large number of different entities, playing in a dynamic scene to obtain the best advantages and profits. This paper presents the development of a metalearner, applied to the decision support of electricity markets’ negotia-tion entities. The proposed metalearner takes advantage on several learning algorithms implemented in ALBidS, an adaptive learning system that pro-vides decision support to electricity markets’ participating players. Using the outputs of each different strategy as inputs, the metalearner creates its own output, considering each strategy with a different weight, depending on its individual quality of performance. The results of the proposed meth-od are studied and analyzed using MASCEM - a multi-agent electricity market simulator that models market players and simulates their operation in the market. This simulator provides the chance to test the metalearner in scenarios based on real electricity market´s data.

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As conexões entre os níveis corticais e sub-corticais na activação da marcha Humana carecem de discussão. As alterações da marcha por lesão no território da Artéria Cerebral Média (ACM) podem ser explicadas pela disfunção de circuitos neuronais dos Núcleos da Base ao córtex e Núcleos Pedúnculo-Pontino. Este trabalho tem como objectivo identificar os percursos anatómicos das principais conexões entre as estruturas encefálicas referidas no território da ACM. Com base na topografia das conexões neuronais, é aceitável que as alterações da marcha sejam explicadas por alterações na função dos Núcleos da Base, através das suas conexões, enquanto moduladores da actividade motora.

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Anaemia has a significant impact on child development and mortality and is a severe public health problem in most countries in sub-Saharan Africa. Nutritional and infectious causes of anaemia are geographically variable and anaemia maps based on information on the major aetiologies of anaemia are important for identifying communities most in need and the relative contribution of major causes. We investigated the consistency between ecological and individual-level approaches to anaemia mapping, by building spatial anaemia models for children aged ≤15 years using different modeling approaches. We aimed to a) quantify the role of malnutrition, malaria, Schistosoma haematobium and soil-transmitted helminths (STH) for anaemia endemicity in children aged ≤15 years and b) develop a high resolution predictive risk map of anaemia for the municipality of Dande in Northern Angola. We used parasitological survey data on children aged ≤15 years to build Bayesian geostatistical models of malaria (PfPR≤15), S. haematobium, Ascaris lumbricoides and Trichuris trichiura and predict small-scale spatial variation in these infections. The predictions and their associated uncertainty were used as inputs for a model of anemia prevalence to predict small-scale spatial variation of anaemia. Stunting, PfPR≤15, and S. haematobium infections were significantly associated with anaemia risk. An estimated 12.5%, 15.6%, and 9.8%, of anaemia cases could be averted by treating malnutrition, malaria, S. haematobium, respectively. Spatial clusters of high risk of anaemia (>86%) were identified. Using an individual-level approach to anaemia mapping at a small spatial scale, we found that anaemia in children aged ≤15 years is highly heterogeneous and that malnutrition and parasitic infections are important contributors to the spatial variation in anemia risk. The results presented in this study can help inform the integration of the current provincial malaria control program with ancillary micronutrient supplementation and control of neglected tropical diseases, such as urogenital schistosomiasis and STH infection.

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This paper presents an integrated system that helps both retail companies and electricity consumers on the definition of the best retail contracts and tariffs. This integrated system is composed by a Decision Support System (DSS) based on a Consumer Characterization Framework (CCF). The CCF is based on data mining techniques, applied to obtain useful knowledge about electricity consumers from large amounts of consumption data. This knowledge is acquired following an innovative and systematic approach able to identify different consumers’ classes, represented by a load profile, and its characterization using decision trees. The framework generates inputs to use in the knowledge base and in the database of the DSS. The rule sets derived from the decision trees are integrated in the knowledge base of the DSS. The load profiles together with the information about contracts and electricity prices form the database of the DSS. This DSS is able to perform the classification of different consumers, present its load profile and test different electricity tariffs and contracts. The final outputs of the DSS are a comparative economic analysis between different contracts and advice about the most economic contract to each consumer class. The presentation of the DSS is completed with an application example using a real data base of consumers from the Portuguese distribution company.

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OBJETIVO: Descrever o uso de medicamentos por idosos, avaliar a presença de polifarmácia, os efeitos de características sociodemográficas e as condições de saúde no uso da medicação. MÉTODOS: Pesquisa de estudo transversal, realizado em 2001 e 2002, em Porto Alegre, no Estado do Rio Grande do Sul, em uma amostra de 215 idosos. Os dados sobre o uso de medicamentos foram coletados por meio de um questionário preenchido durante visita domiciliar. Os medicamentos foram classificados de acordo com Anatomical-Therapeutical-Chemical Classification System. RESULTADOS: Dos entrevistados, 141 (66%) eram mulheres; 117 (54%) na faixa etária entre 60 e 70 anos, 157 (73%) brancos, 115 (53%) tinham companheiros(as) e 145 (67%) cursaram até o ensino fundamental. A prevalência de uso de medicação foi de 91% (n=195). Na semana anterior à entrevista foram utilizados 697 medicamentos, com média de 3,2 (DP=2,5) medicamentos por pessoa. Do total da amostra, 187 (87%) haviam realizado no mínimo uma consulta médica no último ano, 71 (33%) pessoas usavam medicamento sem prescrição médica e em 57 (27%) casos foi caracterizada polifarmácia. CONCLUSÕES: Constatou-se padrão elevado de uso de medicamentos entre pessoas de faixa etária igual ou superior a 60 anos que vivem na comunidade, com pequenas variações conforme as condições de saúde e características sociodemográficas.