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The IDEAL cracking test was developed in 2019 in the Texas A&M Transportation Institute as an alternative to evaluate the fracture tolerance of asphalt mixtures by the same indirect tensile strength test but with a different interpretation. In this methodology, the fracture area is described as a plane surface. However, the fracture of the asphalt mix is characterized by its irregularity and a non-uniform failure surface. For this reason, this work presents a model to determine the actual area of the failure for a set of asphalt mixtures with different characteristics using a 3D scanner. The main goal is to determine a possible correction factor of the actual fracture surface and observe the IDEAL test modification. This study shows that it is possible to standardize the correction factor for four of the five mixtures. more...

Contains fulltext : 175717.pdf (Publisher’s version ) (Open Access) INTRODUCTION: The increased availability of influenza surveillance data in recent years justifies an actual and more complete overview of influenza epidemiology in Latin America. We compared the influenza surveillance systems and assessed the epidemiology of influenza A and B, including the spatio-temporal patterns of influenza epidemics, in ten countries and sub-national regions in Latin America. METHODS: We aggregated the data by year and country and characteristics of eighty-two years were analysed. We calculated the median proportion of laboratory-confirmed influenza cases caused by each virus strain, and compared the timing and amplitude of the primary and secondary peaks between countries. RESULTS: 37,087 influenza cases were reported during 2004-2012. Influenza A and B accounted for a median of 79% and, respectively, 21% of cases in a year. The percentage of influenza A cases that were subtyped was 82.5%; for influenza B, 15.6% of cases were characterized. Influenza A and B were dominant in seventy-five (91%) and seven (9%) years, respectively. In half (51%) of the influenza A years, influenza A(H3N2) was dominant, followed by influenza A(H1N1)pdm2009 (41%) and pre-pandemic A(H1N1) (8%). The primary peak of influenza activity was in June-September in temperate climate countries, with little or no secondary peak. Tropical climate countries had smaller primary peaks taking place in different months and frequently detectable secondary peaks. CONCLUSIONS: We found that good influenza surveillance data exists in Latin America, although improvements can still be made (e.g. a better characterization of influenza B specimens); that influenza B plays a considerable role in the seasonal influenza burden; and that there is substantial heterogeneity of spatio-temporal patterns of influenza epidemics. To improve the effectiveness of influenza control measures in Latin America, tropical climate countries may need to develop innovative prevention strategies specifically tailored to the spatio-temporal patterns of influenza in this region. more...

El cáncer cervical puede ser curado si se detecta y trata oportunamente, para ello la prueba Pap ha sido fundamental. En este contexto, una ayuda tecnológica puede reducir la naturaleza subjetiva del diagnóstico, pero existen dificultades en su construcción. Aquí abordamos dos de ellas: la identificación del citoplasma y el núcleo de cada célula, y la determinación de un conjunto de características relevantes para la detección de lesiones neoplásicas. En este artículo presentamos dos aportes. Primero se propone un método interactivo de segmentación basado en procesamiento morfológico multiespectral en el que las imperfecciones más engañosas de las imágenes son eliminadas con una interacción simple del analista. Segundo, se hace un análisis de la relevancia de algunas variables que caracterizan los tamaños relativos del núcleo y el citoplasma, sus formas, sus texturas y la rugosidad de sus bordes. El análisis se basa en las medidas de desempeño de un detector que utiliza extracción de características mediante análisis de componentes principales (PCA) y separación de células normales y lesionadas mediante una máquina de vectores de soporte (SVM). Encontramos que una mínima interacción con el médico permite obtener segmentaciones mucho más precisas y confiables. De otro lado, encontramos que las características más relevantes para detección de lesiones neoplásicas son los tamaños relativos del núcleo y del citoplasma y sus formas, mientras que otras características, como la textura y la rugosidad, son menos relevantes. Cervical cancer can be cured if detected and treated early, for which the Pap test has been fundamental. In this context, technological aids can reduce the subjective nature of the diagnosis, although there are still several issues to be solved. Here we address two of them: the identification of the cytoplasm and the nucleus in a cell image, and the determination of a set of relevant features for the detection of injured cells. In this paper we present two contributions. First, we propose an interactive segmentation method based on multispectral morphological processing in which most misleading imperfections are eliminated with a simple interaction of the analyst. Second, we made an analysis of the relevance of certain variables that characterize the relative sizes of nucleus and cytoplasm, their shapes, textures and roughness of the edges. The analysis is based on performance measures of a detector that uses feature extraction through principal component analysis (PCA) and separation of normal and injured cells by a support vector machine (SVM). We have found that minimal interaction with the physician allows for much more accurate and reliable segmentation than purely automatic methods. On the other hand, we have found that the most important characteristics for detection of injured cells are the relative sizes of the nucleus and the cytoplasm and their form, while other features, such as texture and roughness, are less relevant. more...

En el siguiente trabajo se tiene como misión dejar reflejado la fabricación y análisis de dos dispositivos para la marcha mediante la recopilación de historias clínicas, exámenes físicos, exámenes musculo-articulares que ayudan a la correcta prescripción de los aparatos, además de un marco teórico de la patología o suceso que las causo. Se pretende que con la correcta adaptación de estos aparatos se obtenga un resultado satisfactorio para la mejora de vida de los usuarios. A su vez para efectos de didácticos se elaborará un análisis de costos, que tienen como finalidad hacer un estimado de todos los factores que entran en el campo administrativo de un laboratorio ortopédico. more...

El objetivo principal de este estudio observacional, fue establecer un puntaje de riesgo para morbilidad y mortalidad intrahospitalaria en pacientes sometidos a intervención coronaria percutánea luego de sufrir alguno de los siguientes síndromes coronarios agudos: angina inestable, infarto agudo del miocardio sin elevación del segmento ST o infarto agudo del miocardio con elevación del segmento ST. Se realizó una recolección de datos clínicos y demográficos a partir de 1.310 pacientes atendidos en la clínica, entre 2003 a 2006, de manera retro-prospectiva, con el fin de elaborar un puntaje válido para la población colombiana. Esto se realizó mediante una base de datos de múltiples variables pre-procedimiento (antecedentes personales), variables intra-procedimiento (tiempo transcurrido desde la hora de la consulta al servicio de urgencias hasta el momento del cateterismo, número de vasos enfermos entre otros) y variables post-procedimientos (complicaciones de morbi-mortalidad). Luego, el análisis de los datos se llevó a cabo mediante un modelo de regresión logística, para determinar cuáles de los factores de riesgo fueron estadísticamente significativos para causar alguno de los resultados evaluados. Los principales resultados evaluados fueron: muerte, eventos hematológicos adversos y estancia hospitalaria. Luego del análisis se encontró que los principales factores relacionados con la morbi-mortalidad de los pacientes fueron el tipo de paciente (o tipo de síndrome coronario sufrido), su edad y su estado hemodinámico al ingreso (presencia de shock cardiogénico). A partir de estos resultados, se desarrolló el puntaje de riesgo a través de las variables pre-operatorias e intra-operatorias. The main objective of this observational study was to establish a mortality risk score for intra-hospital morbidity and mortality in patients submitted to percutaneous coronary intervention (PCI) after having suffered one of the following acute coronary syndromes: unstable angina (UA), acute myocardial infarction without ST elevation (NSTEMI) or acute myocardial infarct with ST elevation (STEMI). Clinical and demographic data of 1,300 patients treated in the clinic between 2003 and 2006 were recollected in a retrospective way with the aim of obtaining a valid risk score for the Colombian population. This was realized through a data base of multiple pre-procedure variables (personal antecedents), intra-procedure variables (time elapsed since the arrival to ER to the moment of catheterization and number of diseased vessels among others) and post-procedure variables (morbimortality complications). Data analysis was then performed through a logistic regression model in order to determine which risk factors were statistically significant in causing some of the results evaluated. The principal results evaluated were death, adverse hematological events and hospital stay; after the analysis we found that the main factors related to patients’ morbimortality, were the type of patient (or the type of coronary syndrome suffered), age and homodynamic state at admission (presence of cardiogenic shock). From these results a risk score through pre-procedure, post-procedure and intra-hospital variables was developed. more...