Automatic segmentation of a meningioma using a computational technique in magnetic resonance imaging

Through this work we propose a computational techniquefor the segmentation of a brain tumor, identified as meningioma(MGT), which is present in magnetic resonance images(MRI). This technique consists of 3 stages developed inthe three-dimensional domain: pre-processing, segmentationand post-processing. The percent relative error (PrE) is consideredto compare the segmentations of the MGT, generatedby a neuro-oncologist manually, with the dilated segmentationsof the MGT, obtained automatically. The combination ofparameters linked to the lowest PrE, provides the optimal parametersof each computational algorithm that makes up theproposed computational technique. Results allow reporting aPrE of 1.44%, showing an excellent correlation between themanual segmentations and those produced by the computationaltechnique developed

Segmentación automática de un meningioma usando una técnica computacional en imágenes de resonancia magnética

Through this work we propose a computational technique for the segmentation of a brain tumor, identified as meningioma (MGT), which is present in magnetic resonance images (MRI). This technique consists of 3 stages developed in the three-dimensional domain: pre-processing, segmentation and post-processing. The percent relative error (PrE) is considered to compare the segmentations of the MGT, generated by a neuro-oncologist manually, with the dilated segmentations of the MGT, obtained automatically. The combination of parameters linked to the lowest PrE, provides the optimal parameters of each computational algorithm that makes up the proposed computational technique. Results allow reporting a PrE of 1.44%, showing an excellent correlation between the manual segmentations and those produced by the computational technique developed.Este trabajo propone una técnica computacional para la segmentación de un tumor cerebral, identificado como meningioma (MGT), que está presente en imágenes de resonancia magnética (MRI). Esta técnica consta de 3 etapas desarrolladas en el dominio tridimensional: preprocesamiento, segmentación y postprocesamiento. El porcentaje de error relativo (PrE) se considera para comparar las segmentaciones de la MGT, generadas por un neurooncólogo de forma manual, con las segmentaciones dilatadas de la MGT, obtenidas automáticamente. La combinación de parámetros vinculados al PrE más bajo proporciona los parámetros óptimos de cada algoritmo computacional que conforma la técnica de cálculo propuesta. Los resultados permiten informar un PrE de 1.44%, mostrando una excelente correlación entre las segmentaciones manuales y las producidas por la técnica computacional desarrollada

Filtros suavizadores en imágenes sintéticas de resonancia magnética cerebral: un estudio comparativo

This paper presents the evaluation of two computational techniques for smoothing noise that might be present in synthetic images or numerical phantoms of magnetic resonance (MRI). The images that will serve as the databases (DB) during the course of this evaluation are available freely on the Internet and are reported in specialized literature as synthetic images called BrainWeb. The images that belong to this DB were contaminated with Rician noise, this being the most frequent type of noise in real MRI images. Also, the techniques that are usually considered to minimize the impact of Rician noise on the quality of BrainWeb images are matched with the Gaussian filter (GF) and an anisotropic diffusion filter, based on the gradient of the image (GADF). Each of these filters has 2 parameters that control their operation and, therefore, undergo a rigorous tuning process to identify the optimal values that guarantee the best performance of both the GF and the GADF. The peak of the signal-to-noise ratio (PSNR) and the computation time are considered as key elements to analyze the behavior of each of the filtering techniques applied. The results indicate that: a) both filters generate PSNR values comparable to each other. b) The GF requires a significantly shorter computation time to soften the Rician noise present in the considered DB. Keywords: Synthetic Cerebral images, Magnetic resonance, Rician noise, Gaussian filter, Anisotropic diffusion filter, PSNR.Este artículo presenta la evaluación de dos técnicas computacionales para el suavizado de ruido, que puede estar presente en imágenes sintéticas o phantoms numéricos de resonancia magnética (MRI). Las imágenes que servirán como bases de datos (DB) para el desarrollo de la mencionada evaluación están disponibles, de manera libre, en la Internet y se reportan, en la literatura especializada, como imágenes sintéticas denominadas BrainWeb. Las imágenes pertenecientes a esta DB fueron contaminadas con ruido Riciano debido a que este es el tipo de ruido más frecuente en imágenes de MRI reales. Por otra parte, las técnicas consideradas para minimizar el impacto de este ruido, en la calidad de las imágenes de la BrainWeb, se hacen coincidir con el filtro Gausiano (GF) y un filtro de difusión anisotrópica, basado en el gradiente de la imagen (GADF). Cada uno de estos filtros posee 2 parámetros que controlan su funcionamiento y, por ende, deben someterse a un proceso de entonación riguroso para identificar los valores óptimos que garanticen el mejor desempeño tanto del GF como del GADF. El pico de la relación señal a ruido (PSNR) y el tiempo de cómputo son considerados como elementos clave para analizar el comportamiento de cada una de las técnicas de filtrado aplicadas. Los resultados indican que: a) Ambos filtros generan valores de PSNR comparables entre sí. b) El GF requiere de un tiempo de cómputo, significativamente, menor para suavizar el ruido Riciano presente en la DB considerada. Palabras clave: Imágenes sintéticas cerebrales, Resonancia magnética, Ruido Riciano, Filtro Gausiano, Filtro de difusión anisotrópica, PSNR

Avances y problemáticas de la justicia transicional en Norte de Santander

El presente artículo de revisión tiene por objeto analizar las diferentes causas que han llevado a Colombia a la implementación de la justicia transicional, partiendo de un estudio documental y hermenéutico, desarrollando un análisis que se remonta en la historia a los juicios de la Segunda Guerra Mundial a través de los tribunales ad hoc, los cuales fueron creados para juzgar conflictos de mayor relevancia a nivel mundial, como los de Nuremberg, Yugoslavia, Ruanda; partiendo del ser humano como autor de democracias y dictaduras, en constante y ardua búsqueda del fi n de la violencia, empleando los Derechos Humanos como protector de las víctimas de atrocidades de actores armados existentes, para el esclarecimiento de la verdad, la justicia y reparación. Además se analiza la confrontación entre la disfunción y desigualdad social en casos especiales como el Catatumbo en Norte de Santander, donde se puede llegar a concluir que dicha región se ve altamente afectada por falta de legitimidad, impidiéndose o limitándose la gobernabilidad del Departamento, conllevando a que el asentamiento de grupos armados ejerzan control del territorio, así como el abandono de hectáreas por parte de la población desplazada forzadamente. AbstractThe present article of review has as aims to analyze the various cause that have led Colombia to the implementation of transitional justice, from a hermeneutic and documentary study, and by developing an analysis that goes back in history to the trials of World War II through of the ad hoc tribunals, which were established to try most important confl icts worldwide, such as Nuremberg, Yugoslavia, Rwanda, based on the human being as the author of democracies and dictatorships, in constant and arduous search for an end to violence, using human rights as protector of the victims of atrocities of armed actors existing for the elucidation of truth, justice and reparation. It also examines the confrontation between dysfunction and social inequality in special cases like the Catatumbo in Norte de Santander, where we can come to the conclusion that this region is highly affected by lack of legitimacy, preventing or limiting the Department’s governance, leading to that the settlement of armed groups exercise control of the territory and the abandonment of hectares by the forcibly displaced

Semiótica: Un recurso fundamental en los procesos de argumentación matemática escrita

Every process of written mathematical argumentation, requires a high level of management of semiotic records, articulating semantic structures capable of meaning. This manuscript shows the results of the research project entitled “Analysis and interpretation of semiotics in the processes of mathematical argumentation, written by the 9th grade students of the Gonzalo Rivera Laguado School in Cúcuta”, the study was assumed from theories surrounding the semiotics and mathematical argumentation, proposed by Peirce, Bachelard, Vygotsky and Duval. The research was developed under the quantitative methodology with a descriptive scope. The esults showed that in the analyzed processes of written mathematica argumentation, the argument loses its strength and relevance due to the inappropriate use of semiotic resources, evidencing conceptual gaps that generate epistemological gaps in mathematical knowledge

Macro-collaborative project a theology to the care of life teachability from the subject's story in the case of Amparo Daza Delgado, Angelina Cárdenas Hernández, Felipe Castro Arboleda and Yudith Contreras Torres

Este trabajo de grado Macro-colaborativo denominado “Una teología al cuidado de la vida enseñabilidad desde el relato del sujeto en el caso de Amparo Daza Delgado, Angelina Cárdenas Hernández, Felipe Castro Arboleda y Yudith Contreras Torres” tiene como objetivo: posibilitar desde el relato de las personas la enseñabilidad de una teología al cuidado de la vida desde la realidad de violencia que enfrentan las comunidades. Para cuyo fin, la pregunta que orienta esta investigación es ¿Cómo posibilitar desde el relato de las personas la enseñabilidad de una teología al cuidado de la vida en comunidades afectadas por la violencia? Para dar respuesta a esta pregunta, se desarrollan tres momentos así: testimonial, en el que se obtienen los soportes para la construcción del relato; interpretativo, que parte de la apropiación del marco teórico y de las categorías de Historia, Educabilidad, Violencia y Cuidado de la Vida, para desarrollar la categorización y agrupación del relato, a fin de realizar la interpretación que nos conduce al tercer momento, el propositivo-liberador, en el cual, se da respuesta a la pregunta problema y se aportan las conclusiones que permiten reflexionar y encontrarnos con la experiencia del otro que nos invita a salir de nosotros mismos.This work of Macro-collaborative degree called “A theology to the care of life teachable from the subject's story in the case of Amparo Daza Delgado, Angelina Cárdenas Hernández, Felipe Castro Arboleda and Yudith Contreras Torres” aims to: from the story of people the teaching of a theology to the care of life from the reality of violence that communities face. To which end, the question that guides this research is: How to enable the teaching of a theology to care for life in communities affected by violence? To answer this question, three moments are developed like this: testimonial, in which the supports for the construction of the story are obtained; interpretive, based on the appropriation of the theoretical framework and the categories of History, Educability, Violence and Life Care, to develop the categorization and grouping of the story, in order to perform the interpretation that leads us to the third moment, the purpose -liberator, in which, the answer to the problem question is given and the conclusions are provided that allow us to reflect and meet the experience of the other that invites us to leave ourselves.Licenciado (a) en Ciencias ReligiosasPregrad

Mathematical argumentation in the classroom

The article shares some elements of comprehensive type about "mathematical argumentation in the classroom"; whose analysis, was made from two fundamental categories in the development of an oral mathematical argumentation process for the conviction, contradiction and validation of a written mathematical argumentation process. The research addressed two central categories of argumentation as a discursive form, the first one is the epistemic position, and the second one is the discursive position that students unveil at the time of mathematically arguing the solution to a problem situation. The research was developed under the interpretative paradigm through the design of a case study directed by the theory and technique of a focal group, for the collection of information. In the findings, difficulties in the passage were evidenced from the semantic to the theoretical from the epistemic position; regarding the discursive position, the presence of three discursive forms was revealed: description, explanation and argumentation, the latter being the least used by the students

Filtros suavizadores en imágenes sintéticas de resonancia magnética cerebral: un estudio comparativo

This paper presents the evaluation of two computational techniques for smoothing noise that might be present in synthetic images or numerical phantoms of magnetic resonance (MRI). The images that will serve as the databases (DB) during the course of this evaluation are available freely on the Internet and are reported in specialized literature as synthetic images called BrainWeb. The images that belong to this DB were contaminated with Rician noise, this being the most frequent type of noise in real MRI images. Also, the techniques that are usually considered to minimize the impact of Rician noise on the quality of BrainWeb images are matched with the Gaussian filter (GF) and an anisotropic diffusion filter, based on the gradient of the image (GADF). Each of these filters has 2 parameters that control their operation and, therefore, undergo a rigorous tuning process to identify the optimal values that guarantee the best performance of both the GF and the GADF. The peak of the signal-to-noise ratio (PSNR) and the computation time are considered as key elements to analyze the behavior of each of the filtering techniques applied. The results indicate that: a) both filters generate PSNR values comparable to each other. b) The GF requires a significantly shorter computation time to soften the Rician noise present in the considered DB.Este artículo presenta la evaluación de dos técnicas computacionales para el suavizado de ruido, que puede estar presente en imágenes sintéticas o phantoms numéricos de resonancia magnética (MRI). Las imágenes que servirán como bases de datos (DB) para el desarrollo de la mencionada evaluación están disponibles, de manera libre, en la Internet y se reportan, en la literatura especializada, como imágenes sintéticas denominadas BrainWeb. Las imágenes pertenecientes a esta DB fueron contaminadas con ruido Riciano debido a que este es el tipo de ruido más frecuente en imágenes de MRI reales. Por otra parte, las técnicas consideradas para minimizar el impacto de este ruido, en la calidad de las imágenes de la BrainWeb, se hacen coincidir con el filtro Gausiano (GF) y un filtro de difusión anisotrópica, basado en el gradiente de la imagen (GADF). Cada uno de estos filtros posee 2 parámetros que controlan su funcionamiento y, por ende, deben someterse a un proceso de entonación riguroso para identificar los valores óptimos que garanticen el mejor desempeño tanto del GF como del GADF. El pico de la relación señal a ruido (PSNR) y el tiempo de cómputo son considerados como elementos clave para analizar el comportamiento de cada una de las técnicas de filtrado aplicadas. Los resultados indican que: a) Ambos filtros generan valores de PSNR comparables entre sí. b) El GF requiere de un tiempo de cómputo, significativamente, menor para suavizar el ruido Riciano presente en la DB considerada

Smoothing filters in synthetic cerebral magnetic resonance images: A comparative study

This paper presents the evaluation of two computationaltechniques for smoothing noise that might be presentin synthetic images or numerical phantoms of magneticresonance (MRI). The images that will serve as the databases(DB) during the course of this evaluation are availablefreely on the Internet and are reported in specializedliterature as synthetic images called BrainWeb. Theimages that belong to this DB were contaminated withRician noise, this being the most frequent type of noisein real MRI images. Also, the techniques that are usuallyconsidered to minimize the impact of Rician noise on thequality of BrainWeb images are matched with the Gaussianfilter (GF) and an anisotropic diffusion filter, based onthe gradient of the image (GADF). Each of these filters has2 parameters that control their operation and, therefore,undergo a rigorous tuning process to identify the optimalvalues that guarantee the best performance of both theGF and the GADF. The peak of the signal-to-noise ratio(PSNR) and the computation time are considered as keyelements to analyze the behavior of each of the filteringtechniques applied. The results indicate that: a) both filtersgenerate PSNR values comparable to each other. b)The GF requires a significantly shorter computation timeto soften the Rician noise present in the considered DB

Volumetry of epidural hematomas in computed tomography images: Comparative study between linear and volumetric methods

This work evaluates the performance of somemethods employed for assessing the volume ofseven subdural hematomas (EDH), present inmulti-layer computed tomography images. Firstly, a referencevolume is considered to be that obtained by a neurosurgeonusing the manual planimetric method (MPM).Secondly, the volume of the 7 EDHs is obtained consideringboth the original version of the ABC/2 method and two ofits variants, identified in this paper as ABC/3 method and2ABC/3 method. The ABC methods allow for calculationof the volume of the hematoma under the assumptionthat the EDH has an ellipsoidal shape. In third place, anintelligent automatic technique (SAT) is implemented thatgenerates the three-dimensional segmentation of eachEDH and from it the volume of the hematoma is calculated.The SAT consists of the pre-processing, segmentationand post-processing stages. In order to make judgmentsabout the performance of the SAT, the Dice coefficient(Dc) is used to compare the dilated segmentations of theEDH with the EDH segmentations generated manually. Finally,the percentage relative error is calculated as a metricto evaluate the methodologies considered. The resultsshow that the SAT method exhibits the best performancegenerating an average percentage error of less than 2%