944 resultados para automated text classification


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Chronic Liver Disease is a progressive, most of the time asymptomatic, and potentially fatal disease. In this paper, a semi-automatic procedure to stage this disease is proposed based on ultrasound liver images, clinical and laboratorial data. In the core of the algorithm two classifiers are used: a k nearest neighbor and a Support Vector Machine, with different kernels. The classifiers were trained with the proposed multi-modal feature set and the results obtained were compared with the laboratorial and clinical feature set. The results showed that using ultrasound based features, in association with laboratorial and clinical features, improve the classification accuracy. The support vector machine, polynomial kernel, outperformed the others classifiers in every class studied. For the Normal class we achieved 100% accuracy, for the chronic hepatitis with cirrhosis 73.08%, for compensated cirrhosis 59.26% and for decompensated cirrhosis 91.67%.

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In this work the identification and diagnosis of various stages of chronic liver disease is addressed. The classification results of a support vector machine, a decision tree and a k-nearest neighbor classifier are compared. Ultrasound image intensity and textural features are jointly used with clinical and laboratorial data in the staging process. The classifiers training is performed by using a population of 97 patients at six different stages of chronic liver disease and a leave-one-out cross-validation strategy. The best results are obtained using the support vector machine with a radial-basis kernel, with 73.20% of overall accuracy. The good performance of the method is a promising indicator that it can be used, in a non invasive way, to provide reliable information about the chronic liver disease staging.

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In this work liver contour is semi-automatically segmented and quantified in order to help the identification and diagnosis of diffuse liver disease. The features extracted from the liver contour are jointly used with clinical and laboratorial data in the staging process. The classification results of a support vector machine, a Bayesian and a k-nearest neighbor classifier are compared. A population of 88 patients at five different stages of diffuse liver disease and a leave-one-out cross-validation strategy are used in the classification process. The best results are obtained using the k-nearest neighbor classifier, with an overall accuracy of 80.68%. The good performance of the proposed method shows a reliable indicator that can improve the information in the staging of diffuse liver disease.

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Steatosis, also known as fatty liver, corresponds to an abnormal retention of lipids within the hepatic cells and reflects an impairment of the normal processes of synthesis and elimination of fat. Several causes may lead to this condition, namely obesity, diabetes, or alcoholism. In this paper an automatic classification algorithm is proposed for the diagnosis of the liver steatosis from ultrasound images. The features are selected in order to catch the same characteristics used by the physicians in the diagnosis of the disease based on visual inspection of the ultrasound images. The algorithm, designed in a Bayesian framework, computes two images: i) a despeckled one, containing the anatomic and echogenic information of the liver, and ii) an image containing only the speckle used to compute the textural features. These images are computed from the estimated RF signal generated by the ultrasound probe where the dynamic range compression performed by the equipment is taken into account. A Bayes classifier, trained with data manually classified by expert clinicians and used as ground truth, reaches an overall accuracy of 95% and a 100% of sensitivity. The main novelties of the method are the estimations of the RF and speckle images which make it possible to accurately compute textural features of the liver parenchyma relevant for the diagnosis.

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Purpose: To describe and compare the content of instruments that assess environmental factors using the International Classification of Functioning, Disability and Health (ICF). Methods: A systematic search of PubMed, CINAHL and PEDro databases was conducted using a pre-determined search strategy. The identified instruments were screened independently by two investigators, and meaningful concepts were linked to the most precise ICF category according to published linking rules. Results: Six instruments were included, containing 526 meaningful concepts. Instruments had between 20% and 98% of items linked to categories in Chapter 1. The highest percentage of items from one instrument linked to categories in Chapters 2–5 varied between 9% and 50%. The presence or absence of environmental factors in a specific context is assessed in 3 instruments, while the other 3 assess the intensity of the impact of environmental factors. Discussion: Instruments differ in their content, type of assessment, and have several items linked to the same ICF category. Most instruments primarily assess products and technology (Chapter 1), highlighting the need to deepen the discussion on the theory that supports the measurement of environmental factors. This discussion should be thorough and lead to the development of methodologies and new tools that capture the underlying concepts of the ICF.

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For some years now, translation theorist and educator Anthony Pym has been trying to establish a dialogue between the academic tradition he comes from and the world of the language industries into which he is meant to introduce his students: in other words, between the Translation Studies discipline and the localisation sector. This rapprochement is also the stated aim of his new book The Moving Text (p. 159). Rather than collect and synthesise what was previously dispersed over several articles, Pym has rewritten his material completely, both literally and conceptually, all in the light of the more than three decades of research he has conducted into the field of cross--cultural communication. The theoretical arguments are ably supported by a few short but telling and well-exploited examples.

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In the hustle and bustle of daily life, how often do we stop to pay attention to the tiny details around us, some of them right beneath our feet? Such is the case of interesting decorative patterns that can be found in squares and sidewalks beautified by the traditional Portuguese pavement. Its most common colors are the black and the white of the basalt and the limestone used; the result is a large variety and richness in patterns. No doubt, it is worth devoting some of our time enjoying the lovely Portuguese pavement, a true worldwide attraction. The interesting patterns found on the Azorean handicrafts are as fascinating and substantial from the cultural point of view. Patterns existing in the sidewalks and crafts can be studied from the mathematical point of view, thus allowing a thorough and rigorous cataloguing of such heritage. The mathematical classification is based on the concept of symmetry, a unifying principle of geometry. Symmetry is a unique tool for helping us relate things that at first glance may appear to have no common ground at all. By interlacing different fields of endeavor, the mathematical approach to sidewalks and crafts is particularly interesting, and an excellent source of inspiration for the development of highly motivated recreational activities. This text is an invitation to visit the nine islands of the Azores and to identify a wide range of patterns, namely rosettes and friezes, by getting to know different arts and crafts and sidewalks.

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Web tornou-se uma ferramenta indispensável para a sociedade moderna. A capacidade de aceder a enormes quantidades de informação, disponível em praticamente todo o mundo, é uma grande vantagem para as nossas vidas. No entanto, a quantidade avassaladora de informação disponível torna-se um problema, que é o de encontrar a informação que precisamos no meio de muita informação irrelevante. Para nos ajudar nesta tarefa, foram criados poderosos motores de pesquisa online, que esquadrinham a Web à procura dos melhores resultados, segundo os seus critérios, para os dados que precisamos. Actualmente, os motores de pesquisa em voga, usam um formato de apresentação de resultados simples, que consiste apenas numa caixa de texto para o utilizador inserir as palavras-chave sobre o tema que quer pesquisar e os resultados são dispostos sobre uma lista de hiperligações ordenada pela relevância que o motor atribui a cada resultado. Porém, existem outras formas de apresentar resultados. Uma das alternativas é apresentar os resultados sobre interfaces em 3 dimensões. É nestes tipos de sistemas que este trabalho vai incidir, os motores de pesquisa com interfaces em 3 dimensões. O problema é que as páginas Web não estão preparadas para serem consumidas por este tipo de motores de pesquisa. Para resolver este problema foi construído um modelo generalista para páginas Web, que consegue alimentar os requisitos das diversas variantes destes motores de pesquisa. Foi também desenvolvido um protótipo de instanciação automático, que recolhe as informações necessárias das páginas Web e preenche o modelo.

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OBJECTIVE: To compare the effectiveness between the see-and-treat (S&T) approach and the conventional one (with prior biopsy) for squamous intraepithelial lesions of uterine cervix. METHODS: A cross-sectional study was conducted with 900 nonpregnant women with cytology suggestive of high grade squamous intraepithelial lesions in the city of Rio de Janeiro, Southeastern Brazil, between 1998 and 2004. The S&T approach consists of a large loop excision of the transformation zone procedure and is recommended when cytology is suggestive of high grade squamous intraepithelial lesion, satisfactory colposcopy with abnormalities compatible with the suspected cytological results, and the lesion is limited to the ectocervix or extends up to one centimeter of the endocervical canal. A subgroup of 336 patients whose colposcopy was considered satisfactory was analyzed, and they were divided into two groups for comparison: patients treated without prior biopsy (n = 288) and patients treated after a biopsy showing high grade squamous intraepithelial lesions (n = 48). Patients who were not treated or only treated more than a year later after recruitment at the colposcopy unit were considered dropouts. RESULTS: Of patients recruited during the study period, 71 were not treated or were only treated for at least a year. The overall dropout rate was 7.9% (95% CI: 6.1;9.7). Mean time elapsed between patient recruitment and treatment was 17.5 days in the S&T group and 102.5 days in the prior biopsy group. Dropout rates were 1.4% (95% CI: 0.04;2.7) and 5.% (95% CI: 0;12.3), respectively (p=0.07). The proportion of overtreated cases (negative histology) in the S&T group was 2.0% (95% CI: 0.4;3.6). CONCLUSIONS: The difference in the mean time elapsed between patient recruitment and treatment indicates that S&T is a time-saving approach The proportion of negative cases from using the S&T approach can be regarded as low.

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OBJECTIVE: To validate a new symphysis-fundal curve for screening fetal growth deviations and to compare its performance with the standard curve adopted by the Brazilian Ministry of Health. METHODS: Observational study including a total of 753 low-risk pregnant women with gestational age above 27 weeks between March to October 2006 in the city of João Pessoa, Northeastern Brazil. Symphisys-fundal was measured using a standard technique recommended by the Brazilian Ministry of Health. Estimated fetal weight assessed through ultrasound using the Brazilian fetal weight chart for gestational age was the gold standard. A subsample of 122 women with neonatal weight measurements was taken up to seven days after estimated fetal weight measurements and symphisys-fundal classification was compared with Lubchenco growth reference curve as gold standard. Sensitivity, specificity, positive and negative predictive values were calculated. The McNemar χ2 test was used for comparing sensitivity of both symphisys-fundal curves studied. RESULTS: The sensitivity of the new curve for detecting small for gestational age fetuses was 51.6% while that of the Brazilian Ministry of Health reference curve was significantly lower (12.5%). In the subsample using neonatal weight as gold standard, the sensitivity of the new reference curve was 85.7% while that of the Brazilian Ministry of Health was 42.9% for detecting small for gestational age. CONCLUSIONS: The diagnostic performance of the new curve for detecting small for gestational age fetuses was significantly higher than that of the Brazilian Ministry of Health reference curve.

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O objetivo do estudo foi comparar os resultados de investigações de acidentes aeronáuticos brasileiros do Centro de Investigação e Prevenção de Acidentes Aeronáuticos (Cenipa) com os do sistema de análise e classificação de fatores humanos (Human Factors Analysis and Classification System - HFACS). Foram analisados e comparados os relatórios finais de 36 investigações de acidentes aeronáuticos ocorridos entre 2000 e 2005, no estado de São Paulo. Foram mencionados 163 fatores contribuintes dos acidentes aeronáuticos nos relatórios do Cenipa, enquanto 370 foram identificados por meio do HFACS. Conclui-se que as análises do Cenipa não contemplaram fatores organizacionais associados aos acidentes aéreos.

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OBJECTIVE: To identify clusters of the major occurrences of leprosy and their associated socioeconomic and demographic factors. METHODS: Cases of leprosy that occurred between 1998 and 2007 in São José do Rio Preto (southeastern Brazil) were geocodified and the incidence rates were calculated by census tract. A socioeconomic classification score was obtained using principal component analysis of socioeconomic variables. Thematic maps to visualize the spatial distribution of the incidence of leprosy with respect to socioeconomic levels and demographic density were constructed using geostatistics. RESULTS: While the incidence rate for the entire city was 10.4 cases per 100,000 inhabitants annually between 1998 and 2007, the incidence rates of individual census tracts were heterogeneous, with values that ranged from 0 to 26.9 cases per 100,000 inhabitants per year. Areas with a high leprosy incidence were associated with lower socioeconomic levels. There were identified clusters of leprosy cases, however there was no association between disease incidence and demographic density. There was a disparity between the places where the majority of ill people lived and the location of healthcare services. CONCLUSIONS: The spatial analysis techniques utilized identified the poorer neighborhoods of the city as the areas with the highest risk for the disease. These data show that health departments must prioritize politico-administrative policies to minimize the effects of social inequality and improve the standards of living, hygiene, and education of the population in order to reduce the incidence of leprosy.

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In the last few years, the number of systems and devices that use voice based interaction has grown significantly. For a continued use of these systems, the interface must be reliable and pleasant in order to provide an optimal user experience. However there are currently very few studies that try to evaluate how pleasant is a voice from a perceptual point of view when the final application is a speech based interface. In this paper we present an objective definition for voice pleasantness based on the composition of a representative feature subset and a new automatic voice pleasantness classification and intensity estimation system. Our study is based on a database composed by European Portuguese female voices but the methodology can be extended to male voices or to other languages. In the objective performance evaluation the system achieved a 9.1% error rate for voice pleasantness classification and a 15.7% error rate for voice pleasantness intensity estimation.

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OBJETIVO: Analisar o padrão de consumo de medicamentos entre idosos e sua associação com aspectos socioeconômicos e autopercepção de saúde. MÉTODOS: Estudo de base populacional e delineamento transversal com 934 idosos de Goiânia, GO, Brasil, entre dezembro de 2009 e abril de 2010. Os dados foram coletados por meio de questionário. As variáveis estudadas foram: número de medicamentos consumidos, sexo, estado civil, escolaridade, tipo de moradia, idade, renda e autopercepção de saúde. Os medicamentos foram classificados segundo o Anatomical Therapeutic and Chemical Classification. Os medicamentos impróprios para idosos foram identificados segundo o Critério de Beers-Fick. Os testes utilizados foram Qui-quadrado (X²) e exato de Fisher e p foi considerado significativo quando < 0,05. RESULTADOS: Os idosos consumiam 2.846 medicamentos (3,63 medicamentos/idoso). Os mais usuais atuavam no aparelho cardiovascular (38,6%). A prevalência de polifarmácia foi de 26,4% e da automedicação de 35,7%. Os medicamentos mais ingeridos por automedicação foram os analgésicos (30,8%); 24,6% dos idosos consumia medicamento considerado impróprio. Mulheres, viúvos, idosos com 80 anos ou mais e com pior autopercepção de saúde praticavam mais a polifarmácia. A maior prática da automedicação esteve associada com menor escolaridade e pior autopercepção de saúde. CONCLUSÕES: O padrão do consumo de medicamentos por idosos foi semelhante ao encontrado em idosos de outras regiões do Brasil. O número de medicamentos usados, a prevalência das práticas da polifarmácia e automedicação e consumo de medicamentos impróprios estiveram dentro da média nacional.