Repositorio Digital Universidad Simón Bolívar
Not a member yet
489 research outputs found
Sort by
Segmentation of epidural hematomas, using a non-linear computational technique in computerized brain tomography images
No full textMediante este trabajo se propone una técnica computacional
no lineal para segmentar un hematoma epidural (EDH), presente
en imágenes de tomografía computarizada multicapa.
Esta técnica consta de 4 etapas desarrolladas en el dominio
tridimensional. Ellas son: pre-procesamiento, segmentación,
pos-procesamiento y entonación de parámetros. La etapa de
pre-procesamiento se divide en dos fases. En la primera, denominada
definición de un volumen de interés (VOI), se emplea
un algoritmo de umbralización por bandas el cual permite,
fundamentalmente, acotar el EDH considerado. En la
segunda fase, identificada como filtrado, se aplica un banco
de algoritmos computacionales para disminuir el impacto de
los artefactos y atenuar el ruido presente en las imágenes. Los
algoritmos que conforman esta fase son: el filtro de erosión
morfológica (MEF) y el filtro de mediana (MF). Por otra parte,
durante la etapa de segmentación se implementa un algoritmo
de agrupamiento, denominado crecimiento de regiones (RG),
el cual es aplicado a las imágenes pre-procesadas. A fin de
compensar el efecto del MEF el EDH, segmentado preliminarmente,
es sometido a la etapa de pos-procesamiento la cual
se basa en la aplicación de un filtro de dilatación morfológica
de tipo binaria (MDF). Durante la entonación de parámetros,
el coeficiente de Dice (Dc) es utilizado para comparar las segmentaciones
dilatadas del EDH, obtenidas automáticamente,
con la segmentación del EDH generada por un neurocirujano
de manera manual. La combinación de parámetros que generan
el Dc más elevado, permite establecer los parámetros
óptimos de cada una de los algoritmos computacionales que
conforman la técnica no lineal propuesta. Los resultados obtenidos
permiten reportar un Dc superior a 0.90 lo cual indica
una buena correlación entre las segmentaciones generadas
por el experto neurocirujano y las producidas por la técnica
computacional desarrollada.The main is to propose a non-linear computational technique
to segment an epidural hematoma (EDH), present in multilayer
computed tomography images. This technique consists
of 4 stages developed in the three-dimensional domain: preprocessing,
segmentation, post-processing and intonation
of parameters. The pre-processing stage is divided into two
phases. In the first one, called the definition of a volume of interest
(VOI), a thresholding algorithm by bands is used, which
allows, fundamentally, to delimit the EDH considered. In the
second phase, identified as filtering, a bank of computational
algorithms is applied to reduce the impact of the artifacts and
attenuate the noise present in the images. The algorithms
that make up this phase are: the morphological erosion filter
(MEF) and the median filter (MF). On the other hand, during
the segmentation stage a grouping algorithm is implemented,
called growth of regions (RG), which is applied to the preprocessed
images. In order to compensate the effect of the
MEF, the EDH, preliminarily segmented, is submitted to the
post-processing stage, which is based on the application of a
morphological dilation filter of binary type (MDF). During the
intonation of parameters, the coefficient of Dice (Dc) is used
to compare the dilated segmentations of the EDH, obtained
automatically, with the segmentation of the EDH generated
by a neurosurgeon manually. The combination of parameters
that generate the highest Dc, allows to establish the optimal
parameters of each of the computational algorithms that
make up the proposed nonlinear technique. The obtained
results allow to report a Dc superior to 0.90 which indicates
a good correlation between the segmentations generated by
the expert neurosurgeon and those produced by the developed
computational technique
Searching for the ideal hypnotic: pharmacological treatment of insomnia
No full textEl insomnio es un trastorno del sueño caracterizado por dificultad
para la conciliación o mantenimiento del sueño, por
disminución del tiempo, fragmentación o mala calidad del
sueño, y sensación de cansancio al día siguiente. Se trata de
un problema con gran prevalencia en países industrializados
y representa uno de los motivos de consulta más frecuente
en atención primaria. Su terapéutica incluye medidas farmacológicas
y no farmacológicas. Las drogas hipnóticas incluyen
un amplio rango de moléculas, como benzodiacepinas,
compuestos Z, antidepresivos, antihistamínicos, entre otros,
cada una con propiedades farmacodinámicas y farmacocinéticas
particulares. Basada en evidencia clínica-epidemiológica,
esta revisión discute la eficacia y seguridad de los fármacos
hipnóticos, con el objetivo de establecer el prototipo de
hipnótico ideal para cada tipo de insomnio, considerando las
necesidades o condiciones del paciente.Insomnia is a sleep disorder characterized by difficulty for the
onset or maintenance of sleep, as well as shortening, fragmentation
or bad quality of sleep, and feeling unrested the
following day. Insomnia boasts a high prevalence in industrialized
countries, and represents one of the most frequent
chief complaints in primary care. Treatment involves pharmacologic
and non-pharmacologic measures. Hypnotic drugs
include a wide range of molecules, such as benzodiazepines,
z compounds, antidepressants, antihistamines and several
others, each with distinct pharmacodynamic and pharmacokinetic
properties. Based on clinical and epidemiologic evidence,
this review discusses the efficacy and safety of hypnotic
drugs, with the objective of establishing the prototype of
the ideal hypnotic for each type of insomnia, according to the
specific needs of each kind of patient
The Influence of Country of Origin Cues on Product Evaluation: Evidence from Swiss and German Consumers
No full textThis study aimed to investigate the influence of visual symbols on the perception and evaluation of two fictitious products as well as the
effect of demographic characteristics (nationality) on consumers’ evaluations. A sample of 373 participants was split into two groups and two experimental
conditions (products with Swiss symbols and products without Swiss symbols). One group of participants rated the packaging without a
Swiss flag and the other one rated the same packaging with a Swiss flag. A semantic differential scale and the Self-Assessment Manikin (SAM) were
used to assess attitudes toward the products. Results confirm that there are differences between the two independent groups and that nationality
has an effect on product perception and evaluation. Visual symbols such as a country flag can lead to a better product perception and evaluation.
Finally, implications for research are discussed
Case Report: An incidentaloma that catches your eye - adrenal myelolipoma [version 1; referees: 2 approved]
No full textBackground: Adrenal incidentaloma refers to the incidental finding of a tumor
in the adrenal gland, where nonfunctional forms are the most common variant.
Myelolipoma is a rare (0.08-0.4%) occurrence characterized by adipose and
hematopoietic tissue. The aim of this case report is to describe the diagnosis
and appropriate management of a myelolipoma in an asymptomatic patient,
which was originally considered an incidental hepatic hemangioma prior to
being identified as a giant adrenal adenoma.
Case description: The patient was a 54 year old obese female with a recent
diagnosis of diabetes type II and dyslipidemia with recent ultrasound imaging
suggestive of a hepatic hemangioma. An MRI was performed revealing a
7x6cm lesion in the right adrenal area indicating a giant adrenal adenoma. An
adrenalectomy was performed without complications. The pathology report
identified a myelolipoma.
Discussion: The incidence of myelolipoma has recently increased due to
advances in radiological techniques. Its etiology is unclear and the most
accepted theories support a myeloid cell metaplasia in the embryonic stage as
a result of stress, infections, or adrenocorticotropic hormone or erythropoietin
stimulus. Contributing components may include bone morphogenetic protein 2
and β-catenin, as well as the presence of the chromosomal translocation (3,
21) (q25; p11). Despite its benign nature, the association with other adrenal
lipomas must be ruled out. A biochemical evaluation is essential for detecting
subclinical states, such as Cushing syndrome and pheochromocytoma.
Conclusion: Adrenal myelolipomas are rare benign tumors that are generally
asymptomatic. Uncertainty still exists surrounding their etiology. Surgical
management depends on hormone production, tumor size, high risk features
on imaging and patient consent. Additional information is needed to better
understand myelolipomas, their etiology, and clinical management.
Incidentalomas may confuse the physician and patient. Ensuring proper
multidisciplinary management based on the clinical guidelines of endocrinology
allowed a satisfactory resolution of this case
Implementation of Clinical Practice Guideline (CPG) for early detection, diagnosis and comprehensive care of the depressive episode and recurrent depressive disorder in adults at Hospital Universitario Cari ESE Neurociencias de Barranquilla (Colombia)
No full textObjetivo: Implementar una Guía de Práctica Clínica (GPC) para la detección temprana y
diagnóstico del episodio depresivo y trastorno depresivo recurrente en adultos en los servicios
de consulta prioritaria, consulta externa y hospitalización del Hospital Universitario Cari
ESE Neurociencias de la ciudad de Barranquilla.
Materiales y métodos: Se desarrolló el Plan de implementación de una GPC de manejo
de episodio depresivo y trastorno depresivo recurrente, de acuerdo con la metodología del
manual de implementación de guías de práctica clínica basadas en evidencia del Ministerio
de Salud. El instrumento de recolección de datos utilizado fue el cuestionario. Se indagó
acerca de la preparación académica, el tiempo laborado en el ESE Cari mental y la experiencia
profesional específica; así como del manejo que tienen en su vida profesional y preferencias
las GPC - depresión. Resultados: La GPC elegida por consenso fue la Guía de Práctica Clínica (GPC) para la
detección temprana y diagnóstico del episodio depresivo y trastorno depresivo recurrente en
adultos, atención integral de los adultos con diagnóstico de episodio depresivo o trastorno
depresivo recurrente.
Conclusiones: La demanda de servicios de salud siempre parece ser superior a la cantidad
de recursos disponibles para satisfacerla. La anterior afirmación es válida en todas las sociedades,
aun en los países clasificados como de altos ingresos. Es por ello que la adopción
de GPC en el contexto clínico-administrativo de la ESE Cari mental –incluyendo los demás
entes territoriales– es una decisión que redunda en la racionalización del recurso humano
y administrativo, el cual siempre será escaso.
Palabras clave: depresión unipolar, Guía de Práctica Clínica, implementación de
plan de salud, Sistema de Salud.Objective: Implement a Clinical Practice Guideline (CPG) for early detection and diagnosis
of depressive episode and recurrent depressive disorder in adults, services for priority
consultation, outpatient and inpatient University Hospital Cari ESE Neurosciences city
Barranquilla.
Materials and methods: Implementation Plan GPC management depressive episode and
recurrent depressive disorder, according to the methodology manual implementation of clinical
practice guidelines based on evidence from the Ministry of Health was developed. The data
collection instrument used was the questionnaire. He asked about academic preparation, the
time worked in the mental Cari and specific professional experience; as well as management
they have in their professional life and preferences CPG - depression.
Results: The GPC was chosen by consensus Clinical Practice Guideline (CPG) for early
detection and diagnosis of depressive episode and recurrent depressive disorder in adults,
comprehensive care of adults diagnosed with depressive episode or recurrent depressive disorder.
Conclusions: The demand for health services always seems to be greater than the amount
of resources available to meet. The above statement is valid in all societies, even in countries
classified as high income. It is therefore that the adoption of GPC in the clinical context-
Administrative of Cari Mental Hospital –including other local authorities– is a decision
that results in the rationalization of human and administrative resource, which will always
be scarce
From Heidegger to Morin: an interpretation since the overcoming metaphysics to the fundaments of the complexity
No full textEste artículo presenta una discusión en torno a la resignificación y la superación
de la metafísica que hace Martin Heidegger, conectando mencionada superación a los
desarrollos epistemológicos del paradigma de la complejidad del intelectual francés
Edgar Morin. En este sentido, se intentará 1) exponer los asuntos de ese trabajo acerca
del pensar metafísico que hace el filósofo alemán a la luz de la historia del Ser y 2)
conectar su agenda final a la paradigmática moraniana, intentando probar que en el
pensamiento de este autor, hay una importante carga heideggeriana no manifiesta, en
el trabajo con conceptos tales como sistema, identidad, tiempo, Dasein, entre otros.This article presents a discussion on the re-signification and overcoming
metaphysics that makes Martin Heidegger, connecting mentioned overcome to the
epistemological developments of the paradigm of the complexity of the French
intellectual Edgar Morin. In this sense, it tries 1) exposing the affairs of this work
about metaphysical thinking that makes the German philosopher in the light of the
history of Being and 2 ) connect your final agenda to the paradigmatic moraniana ,
trying to prove that in the thinking this author , there is an important heideggeriana
mark not load manifest, in the work with concepts such system , identity, time, Dasein,
among others
Pasting and reversing approach to matrix theory
No full textThe aim of this paper is to study some aspects of matrix theory
through pasting and reversing using linear mappings. We obtain new
properties and new sets in matrix theory. In particular, we introduce
new linear mappings: palindromicing and antipalindromicing
mappings, which allow us to obtain palindromic and antipalindromic
vectors and matrices
Monitoring and control of the multihead weighing process through a modified control chart1
No full textModified control charts are used to monitor and control manufacturing processes which are considered to be six-sigma processes. The use of these charts is based on the idea that the cost of identifying and correcting special causes is much higher than the cost of off-target products. Therefore, the process mean is essentially acceptable as long as it is anywhere within the specification limits. These concepts are applied to the packaging process in multihead weighers. The weight of the packed product, seen as the quality characteristic to be monitored, must be as close to a specified target weight as possible and comply with applicable regulations. The packaging process was previously optimized and improved using a packaging strategy, which was evaluated through a proposed packing algorithm. In this way, a set of numerical experiments were conducted to examine the solutions generated, which were subsequently monitored.Los gráficos de control modificados se utilizan para el seguimiento y control de procesos de fabricación que son considerados como procesos seis-sigma. El uso de estos gráficos se basa en la idea de que el costo de identificar y corregir causas especiales de variación es mucho más alto que el costo de productos alejados de su valor nominal. Por lo tanto, la media del proceso es esencialmente aceptable siempre que esté dentro de los límites de especificación. Estos conceptos han sido aplicados al proceso de envasado en pesadoras multicabezal. El peso del producto envasado, visto como la característica de calidad a ser monitoreada, debe ser lo más cercano posible a un peso objetivo y cumplir con la normativa. El proceso ha sido previamente optimizado y mejorado mediante una estrategia de envasado, la cual es evaluada a través de un algoritmo de envasado. De esta manera, un conjunto de experimentos numéricos fueron realizados para examinar las soluciones generadas, las cuales son posteriormente monitoreadas
Modelo de Responsabilidad Social Empresarial para el mejoramiento de comunidades asentadas en un entorno empresarial: Caso mujeres cabeza de familia
No full textEl trabajo nace de la necesidad de las empresas de contar con un programa de responsabilidad social que contribuya con el mejoramiento de su entorno a través de un modelo efectivo que llegue a la comunidad. Para la delimitación del modelo se identificó un grupo de interés seleccionando las comunidades asentadas en el entorno de una unidad empresarial y específicamente mujeres cabezas de familia. Se establece entonces un modelo de responsabilidad social que apunta a mejorar la calidad de vida y el acercamiento de la empresa a la comunidad a partir del sistema de donaciones, donde los recursos económicos (mercancías) se entregan con el objetivo de mejorar el aspecto económico, social y educativo. El modelo diseñado permite un desarrollo social, donde la generación de actividades de Responsabilidad Social Empresarial (RSE) son la base para lograr un bienestar social al grupo objetivo y adicionalmente, se convierte en instrumento para lograr un acercamiento entre la empresa y la comunidad. El modelo opera canalizando mercancías hacia la comunidad, administradas por la empresa, con el propósito de garantizar su correcta disposición.The work stems from the need for companies to have a Corporate Social
Responsibility program contributes to improving the environment through an
effective model that reaches the community. The establishment of the model
identified stakeholders by selecting the communities in the environment of a business unit, specifically women heads of households. Then established a model
of Social Responsibility that aims to improve the quality of life and the company’s
approach to the community from the donation system, where economic resources
(merchandise) are delivered with the aim of improving the economic, social
and educational. The model designed allows for social development, where the
generation of Corporate Social Responsibility activities (CSR) are the basis for
a social welfare in addition to the target, becomes an instrument to achieve a
rapprochement between the company and the community. The model operates
channeling goods to the community, managed by the company, in order to ensure
their proper disposa