49 research outputs found

    Método automático de clasificación de color en dientes humanos usando aprendizaje de máquina

    Get PDF
    Trabajo de InvestigaciónActualmente el proceso de identificación del color de los dientes para la fabricación de prótesis dentales es realizado manualmente por un experto que, utilizando un método de identificación visual, determina el color de las piezas dentales en la boca del paciente, usando guías de color como la VITA®. A pesar de que el método visual es el más utilizado para la identificación del color de dientes, este se ve afectado por distintas variables tales como: el cansancio del experto, la luminosidad en el ambiente, salud visual del especialista, entre otras que influyen en la identificación del color en los dientes. Los errores en la clasificación del color de los dientes pueden generar pérdidas de tiempo lo que implicaría en consecuencia sobrecostos que afectarían directamente al fabricante y la satisfacción final del cliente.1. Planteamiento del problema 2. Pregunta de investigación 3. Objetivos 4. Estado del arte 5. Marco de referencia 6. Alcances y limitaciones 7. Metodología 8. Diseño metodológico 9. Discusión y resultados 10. Conclusiones 11. Trabajos futuros 12. Bibliografía 13. ANEXOSPregradoIngeniero de Sistema

    Modeling Disease Vector Occurrence when Detection Is Imperfect: Infestation of Amazonian Palm Trees by Triatomine Bugs at Three Spatial Scales

    Get PDF
    Blood-sucking bugs of the genus Rhodnius are major vectors of Chagas disease. Control and surveillance of Chagas disease transmission critically depend on ascertaining whether households and nearby ecotopes (such as palm trees) are infested by these vectors. However, no bug detection technique works perfectly. Because more sensitive methods are more costly, vector searches face a trade-off between technical prowess and sample size. We compromise by using relatively inexpensive sampling techniques that can be applied multiple times to a large number of palms. With these replicated results, we estimate the probability of failing to detect bugs in a palm that is actually infested. We incorporate this information into our analyses to derive an unbiased estimate of palm infestation, and find it to be about 50% – twice the observed proportion of infested palms. We are then able to model the effects of regional, landscape, and local environmental variables on palm infestation. Individual palm attributes contribute overwhelmingly more than landscape or regional covariates to explaining infestation, suggesting that palm tree management can help mitigate risk locally. Our results illustrate how explicitly accounting for vector, pathogen, or host detection failures can substantially improve epidemiological parameter estimation when perfect detection techniques are unavailable

    Asma e gravidez: repercussões no recém-nascido

    Get PDF
    OBJETIVO: Descrever, numa coorte de nascimentos, aspectos socioeconômicos e comportamentais de gestantes com asma e analisar as repercussões desta sobre alguns parâmetros perinatais. MÉTODOS: Estudo observacional, transversal e analítico a partir de informações de parturientes da coorte de nascimentos ocorridos no período entre 8 de março e 15 de julho de 2005 nas maternidades da Grande Aracaju (SE). A identificação de asma nas gestantes foi obtida segundo informação destas a partir do diagnóstico emitido anteriormente por um médico. Foram analisadas variáveis epidemiológicas, obstétricas e perinatais. RESULTADOS: Das 4.757 parturientes incluídas no estudo, 299 (6,3%) eram asmáticas. As mães asmáticas tinham menor renda familiar e mais frequentemente procuraram assistência no pré-natal e no parto em serviços públicos que as mães sem asma. Embora somente 9,4% das gestantes asmáticas fumaram, e 27,6% ingeriram bebidas alcoólicas, as proporções em relação ao grupo controle foram significativamente maiores. Não se detectou associação entre asma e problemas obstétricos ou do recém-nascido. Não foi encontrada associação entre asma e parto cesariano, prematuridade ou recém-nascido sendo pequeno para a idade gestacional. CONCLUSÕES: O nível socioeconômico inferior parece ser um fator de risco para a asma

    Understanding the clinical spectrum of complicated Plasmodium vivax malaria: a systematic review on the contributions of the Brazilian literature

    Get PDF
    The resurgence of the malaria eradication agenda and the increasing number of severe manifestation reports has contributed to a renewed interested in the Plasmodium vivax infection. It is the most geographically widespread parasite causing human malaria, with around 2.85 billion people living under risk of infection. The Brazilian Amazon region reports more than 50% of the malaria cases in Latin America and since 1990 there is a marked predominance of this species, responsible for 85% of cases in 2009. However, only a few complicated cases of P. vivax have been reported from this region. A systematic review of the Brazilian indexed and non-indexed literature on complicated cases of vivax malaria was performed including published articles, masters' dissertations, doctoral theses and national congresses' abstracts. The following information was retrieved: patient characteristics (demographic, presence of co-morbidities and, whenever possible, associated genetic disorders); description of each major clinical manifestation. As a result, 27 articles, 28 abstracts from scientific events' annals and 13 theses/dissertations were found, only after 1987. Most of the reported information was described in small case series and case reports of patients from all the Amazonian states, and also in travellers from Brazilian non-endemic areas. The more relevant clinical complications were anaemia, thrombocytopaenia, jaundice and acute respiratory distress syndrome, present in all age groups, in addition to other more rare clinical pictures. Complications in pregnant women were also reported. Acute and chronic co-morbidities were frequent, however death was occasional. Clinical atypical cases of malaria are more frequent than published in the indexed literature, probably due to a publication bias. In the Brazilian Amazon (considered to be a low to moderate intensity area of transmission), clinical data are in accordance with the recent findings of severity described in diverse P. vivax endemic areas (especially anaemia in Southeast Asia), however in this region both children and adults are affected. Finally, gaps of knowledge and areas for future research are opportunely pointed out
    corecore