Estudio sobre la gestión para la construcción de un metro : caso de estudio para la ciudad de Medellín (1979-1983)

A lo largo del tiempo se han construido proyectos de Metro en las grandes ciudades del mundo, brindando una solución radical al problema de movilidad que se presenta hoy en día, las cuales siguen incrementando sus cifras poblacionales y requiriendo sistemas capaces de mover de manera eficaz las grandes masas que se movilizan en su interior todos los días. Con fin de dar a conocer cómo es que se realiza una gestión para la construcción de este tipo de proyectos y basados en el marco de las Múltiples Trayectorias de John Kingdon, el presente artículo describe la gestión que se realizó en el caso específico del metro de Medellín, Colombia, basados en las tres categorías fundamentales encontradas: (1) la problemática que se desea solucionar, (2) el planteamiento de la solución del proyecto Metro desde la perspectiva técnica y (3) la influencia política, llegando finalmente a que dicha gestión tenga éxito y el proyecto cobre vida por medio de una ventana de oportunidad.As metro projects have evolved the development in large cities have provided solutions to the mobility problems, and also to socio-economic issues that affects the rural zones. Nowadays, as populations continue to rise there is a requirement for systems to be able to mobilize effectively large volumes of people who commute every day. In order to show how the management of the construction of a metro project is developed, and based on the Multiple Stream Framework cited by John Kingdon, this paper describes an integrated management system of a metro protect developed, specifically, within Medellin, Colombia. Based on these three main streams: (1) the need to be resolved, (2) the approach to the solution from a technical perspective, and (3) the politic influence.Ingeniero (a) CivilPregrad

Estimation of electron density in the nighttime ionosphere based on remote sensing of the 135.6 nm far ultraviolet emission

This thesis develops a method to accurately estimate the electron density altitude profiles of the nighttime ionosphere, as well as important parameters such as the peak height and density, using nighttime far ultraviolet (FUV) measurements of the 135.6 nm nighttime emissions. Specifically, we will describe a method to accurately obtain the electron density content of the ionosphere by using brightness measurements of the nighttime 135.6 nm emission. The method is applied and tested using simulated measurements to relate to those to be obtained by the limb-viewing FUV instrument on board the Ionospheric Connection Explorer (ICON) satellite scheduled to be launched in 2017. The OI 135.6 nm emission can be used as a proxy of the ionosphere's electron density and is related through an integral equation of the volume emission rate to the brightness measured by the FUV instrument. The instrument's observation geometry allows for the discretization of the problem, thus connecting the ionosphere's electron density with the measured brightness through a matrix equation. Regularization methods are used in order to enforce constraints of smoothness and continuity on the estimation of the volume emission rate, to compensate for the noise amplification in the inversion process. Tikhonov regularization, generalized cross-validation, total variation and Bayesian methods that assume prior knowledge of the ionosphere's electron density distribution are investigated. Comprehensive simulations are used to explore the different brightness intensities for all longitudes, and for latitudes from -40 to 40 degrees, in order to allow the characterization of the effect of different SNR values on the electron density reconstruction accuracy. FUV measurements are simulated using the International Reference Ionosphere (IRI) and Mass Spectrometer and Incoherent Radar (MSIS) models to create a forward model which can be inverted in order to validate the altitude profile reconstruction as well as the peak height and density accuracy. This allows us to investigate the expected performance of the FUV instrument

Lecciones aprendidas en la interventoría del proyecto de construcción de la bodega Distribuidora El Castillo de Antioquia, desarrollado por la empresa Probil Proyectos Inmobiliarios S.A.S.

Con la presente investigación se pretende documentar las lecciones aprendidas en la interventoría del proyecto de construcción de la bodega Distribuidora El Castillo de Antioquia, desarrollada por Probil Proyectos Inmobiliarios, con base en la selección de una metodología para la gestión de lecciones aprendidas, para capitalizar los aprendizajes en futuros proyectos de la organización. Para esto se utilizó una metodología híbrida de los marcos conceptuales de la OTAN, el BID y la de Coquillat de Travesedo, que se desarrolló en tres etapas. La primera de ellas consistió en analizar los documentos contractuales del proyecto, con el fin de describir las acciones que se realizaron durante todo su ciclo de vida. Para la segunda etapa se diseñó una encuesta con preguntas cerradas que se formularon a trece actores involucrados en el proyecto. Con base en los resultados de las encuestas, se identificaron los casos de éxito y fracaso, y se clasificaron en una matriz de grupos de procesos y áreas del conocimiento del PMI®. En la etapa tres se evaluaron las lecciones aprendidas mediante una descripción de las mismas, se estableció una conclusión para cada una de ellas y una recomendación para futuros proyectos de la organización. Los resultados obtenidos fueron ocho casos de éxito que se pueden replicar en el futuro y 18 casos de fracaso que deben tener acciones de mejora.With the present investigation, to document the lessons learned in the supervision of the construction project of the storeroom Distribuidora El Castillo de Antioquia is intended, developed by Probil Proyectos Inmobiliarios S.A.S, based on the selection of a methodology for the management of learned lessons, to capitalize the learning in future projects of the organization. For this, a hybrid methodology of the conceptual frameworks of NATO, the IDB and Coquillat de Travesedo was used, which was developed in three stages. The first of them consisted of analyzing the contractual documents of the project, in order to describe the actions that were developed throughout its life cycle. For the second stage, a survey was designed and were applied to thirteen actors involved in the project. Based on the results of the surveys, the cases of success and failure were identified and classified in a process groups and project management knowledge areas according to the PMI® matrix. In stage three, the learned lessons were evaluated through a description of them, subsequently was established a conclusion of them and a recommendation for future projects of the organization. The results obtained were eight success cases that can be replicated in the future and eighteen failure cases that must have improvement actions

Lista de anfibios y reptiles del departamento del Tolima, Colombia

Se construyó el listado taxonómico de especies de anfibios y reptiles del departamento del Tolima, Colombia, con base en la revisión extensa de literatura e información de colecciones biológicas. El total de especies de anfibios registrados es de 98, de las cuales 91 son ranas y sapos, cuatro caecilias y tres salamandras. Los reptiles reportados son 102, representados por 60 serpientes, 36 lagartos, cuatro tortugas y dos caimanes. La mayor riqueza de herpetofauna del departamento se concentra en las regiones fisiográficas de la cordillera Central y valle interandino del río Magdalena. El estado de amenaza de la herpetofauna tolimense es más crítico para los anfibios que para los reptiles: el 14,4% de los anfibios están categorizados como Vulnerables, el 8,2% En Peligro, el 5,1% Casi Amenazados y el 4,1% en Peligro Crítico. Por su parte, sólo dos especies de reptiles registran algún grado de amenaza. Debido a la representatividad de la herpetofauna del Tolima con respecto a la diversidad colombiana, se hace necesario plantear a nivel regional un plan general de acción para la conservación de los anfibios y reptiles, que considere las estrategias de manejo más favorables para preservar la biodiversidad.Artículo revisado por pare

Presence of Eleutherodactylus johnstonei (ANURA: ELEUTHERODACTYLUS) in Ibague, Tolima, Colombia: the role of commercial garden centers

La rana Coquí de las Antillas Eleutherodactylus johnstonei, es considerada una especie invasora de varios países de Centro y Sur América, la cual puede ocasionar efectos negativos al poner en riesgo la salud del hombre, debido a su aguda vocalización tornándose contaminación auditiva y por ser portadora de parásitos. Con el fin de identificar la fuente de introducción y los mecanismos de dispersión de la especie se reporta y se describe la contribución de los viveros comerciales de la ciudad de Ibagué con la llegada de E. johnstonei a la ciudad y de su posterior dispersión a las zonas residenciales por medio del transporte de plantas ornamentales. Individuos de la especie fueron observados en zonas residenciales y comerciales del centro de la ciudad en 2011, 2012 y 2013. Por medio de visitas nocturnas a viveros y recorridos por la ciudad se identificó la presencia de la especie en nueve de los 12 viveros visitados así como también el registro auditivo en siete barrios residenciales de la ciudad. Entrevistas semiestructuradas con viveristas permitieron identificar que la principal zona de donde se surten las plantas de los viveros ibaguereños es el departamento de Cundinamarca específicamente de los municipios de Fusagasugá y Mesitas del Colegio. Se reporta por primera vez a E. johnstonei en la localidad de Chinauta, Fusagasugá (Cundinamarca). Dadas las implicaciones biológicas y los potenciales impactos económicos de la invasión es necesario plantear estrategias de mitigación que conduzcan a controlar la presencia de la especie en los viveros mayoristas y a los de Ibagué para evitar la dispersión a otras zonas de la ciudad y el país.The "Antilles coquí" frog, Eleutherodactylus johnstonei, is considered an invasive species in several countries of Central and South America which can cause negative effects by putting at risk the health of humans because of its sharp chanting becoming auditory contamination, as well as for being carrier of parasites. In order to identify sources of introduction and mechanisms of dispersion of the species, the contribution of commercial garden centers in the city of Ibagué is reported and described in this article, with the arrival of E. johnstonei to the city and its subsequent dispersion in residential areas through the transportation of ornamental plants. Individuals of the species were observed in residential and commercial downtown areas in 2011, 2012 and 2013. During night visits to commercial garden centers in the city, the presence of the species was identified in nine of the 12 commercial garden centers visited, as well as the acoustic record was done in seven neighborhoods in the city. Semi-structured interviews with keepers helped identifying that the main area from where the plants come is the department of Cundinamarca, specifically from the municipalities of Fusagasugá and Mesitas del Colegio. The E. johnstonei was reported for the first time in the town of Chinauta, Fusagasugá (Cundinamarca). Given the biological implications and potential economic impacts of the invasion, it is necessary to propose mitigation strategies leading to control the presence of the species in wholesale commercial garden centers and those of Ibagué in order to prevent the dispersion to other areas of the city and the country

El bosque seco tropical en Colombia

Más de cuarenta investigadores nacionales e internacionales de más de 20 instituciones contribuyeron a este libro que recoge el estado del conocimiento sobre la biodiversidad, el estado de fragmentación y transformación, y la restauración del bosque seco en Colombia. Sin duda nos quedaron por fuera investigadores e instituciones que realizan un trabajo muy valioso en el BST. Con este libro queremos extenderles la invitación a ellos y a todos los demás interesados en BST para que continúen el trabajo en este ecosistema que es clave para la conservación de la biodiversidad y la provisión de servicios ecosistémicos en áreas secas de Colombia. Sobretodo porque hasta ahora empezamos a entender la importancia ecológica de estos ecosistemas.Bogotá, D. C.Instituto de Investigación de Recursos Biológicos Alexander von Humbold

Effects of pre-operative isolation on postoperative pulmonary complications after elective surgery: an international prospective cohort study an international prospective cohort study

We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05–1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4–7 days or ≥ 8 days of 1.25 (1.04–1.48), p = 0.015 and 1.31 (1.11–1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care. We aimed to determine the impact of pre-operative isolation on postoperative pulmonary complications after elective surgery during the global SARS-CoV-2 pandemic. We performed an international prospective cohort study including patients undergoing elective surgery in October 2020. Isolation was defined as the period before surgery during which patients did not leave their house or receive visitors from outside their household. The primary outcome was postoperative pulmonary complications, adjusted in multivariable models for measured confounders. Pre-defined sub-group analyses were performed for the primary outcome. A total of 96,454 patients from 114 countries were included and overall, 26,948 (27.9%) patients isolated before surgery. Postoperative pulmonary complications were recorded in 1947 (2.0%) patients of which 227 (11.7%) were associated with SARS-CoV-2 infection. Patients who isolated pre-operatively were older, had more respiratory comorbidities and were more commonly from areas of high SARS-CoV-2 incidence and high-income countries. Although the overall rates of postoperative pulmonary complications were similar in those that isolated and those that did not (2.1% vs 2.0%, respectively), isolation was associated with higher rates of postoperative pulmonary complications after adjustment (adjusted OR 1.20, 95%CI 1.05–1.36, p = 0.005). Sensitivity analyses revealed no further differences when patients were categorised by: pre-operative testing; use of COVID-19-free pathways; or community SARS-CoV-2 prevalence. The rate of postoperative pulmonary complications increased with periods of isolation longer than 3 days, with an OR (95%CI) at 4–7 days or ≥ 8 days of 1.25 (1.04–1.48), p = 0.015 and 1.31 (1.11–1.55), p = 0.001, respectively. Isolation before elective surgery might be associated with a small but clinically important increased risk of postoperative pulmonary complications. Longer periods of isolation showed no reduction in the risk of postoperative pulmonary complications. These findings have significant implications for global provision of elective surgical care