190 research outputs found

    Modelos de escorrentía superficial en la última década. Una revisión bibliográfica

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    This paper aims to identify surface runoff patterns over the last decade. A literature review was conducted and 56 studies published in Google Scholar, Red de Revistas Científicas de América Latina y el Caribe, España y Portugal (Redalyc), Difusión de Alerta en la Red (Dialnet), Scientific Electronic Library Online (SciELO) and Science Direct during the period 2012 to 2022 were found. The search was limited to open access scientific articles. A database was generated in Microsoft Excel 2010. Reference, year of publication, journal name, study area, entity, country, research objective, variables used and abbreviation of surface runoff models were recorded. Seven percent of the articles published are concentrated in the journal Tecnología y Ciencias del Agua. Argentina ranks first in published studies and 80% of the study areas are in watersheds.  The most widely used models for estimating, evaluating, predicting, modeling and simulating surface runoff are Soil and Water Assessment Tool (SWAT) and Soil Conservation Service-Curve Number (SCS-CN).Este documento tiene como objetivo identificar modelos de escurrimientos superficiales en la última década. Se realizo una revisión de literatura y se encontraron 56 estudios publicados en los buscadores Google Scholar, Red de Revistas Científicas de América Latina y el Caribe, España y Portugal (Redalyc), Difusión de Alerta en la Red (Dialnet), Scientific Electronic Library Online (SciELO) y Science Direct durante el periodo de 2012 hasta el 2022. La búsqueda se delimitó en artículo científico de libre acceso. Se genero una base de datos en Microsoft Excel 2010. Se registraron referencia, año de publicación, nombre de la revista, área de estudio, entidad, país, objetivo de la investigación, variables utilizadas y abreviación de modelos de escurrimientos superficiales. El 7 % de los artículos publicados se concentran en la revista Tecnología y Ciencias del Agua. Argentina ocupa el primer lugar en estudios publicados y 80 % de las áreas de estudios es en cuencas hidrográficas. Los modelos más utilizados para estimar, evaluar, predecir, modelar y simular los escurrimientos superficiales son Herramienta para la Evaluación del Suelo y Agua (SWAT) y Servicio de Conservación de Suelo-Número de curva (SCS-CN)

    Identificación de zonas de inundación a partir de imágenes (SAR) y de eventos históricos de inundación: caso de estudio Santiago de Cali, Colombia

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    The objective of this work was to identify flood zones in the city of Santiago de Cali Colombia, through historical information and RADAR images. During the process Sentinel 1 images pre and post event were used, and reports of hydrometeorological phenomena (1986-2018) were revisited. The method used corresponds to the framework named methodological complementarity and was carried out with the documentary review, fieldwork and the digital treatment of data based on supervised classification. The results of documentary review and fieldwork indicate the occurrence of 766 events associated with floods that have affected 186 neighborhoods in a period of 32 years. In addition to this, digital image processing identified 2082, 25 hectares of floodplains, with overall reliability of 89 percent. Kappa index of 0.76 percent. It is important to note that the majority of water plates were located in areas adjacent to the Cauca, Cali and Interceptor Sur and Oriental channels.El objetivo de este trabajo fue identificar zonas de inundación en la ciudad de Santiago de Cali Colombia, mediante imágenes de RADAR e información histórica. Durante el proceso se utilizaron imágenes Sentinel 1 pre y post evento y reportes de fenómenos hidrometereológicos (1986-2018). El método empleado precisó un abordaje desde diferentes ángulos, en lo que se enmarca como complementariedad metodológica. Consistió en una revisión documental, reconocimiento de campo, y el tratamiento digital de datos a partir de clasificación supervisada. Los resultados de la revisión documental y el trabajo de campo indican la ocurrencia de 766 eventos asociados a inundación que han afectado a 186 barrios en un periodo de 32 años. Además de esto, el procesamiento digital de las imágenes identificó 2082, 25 hectáreas inundables, con fiabilidad global del 89 por ciento e índice Kappa de 0.76 por ciento. Es importante resaltar que la mayoría de áreas inundables se localizaron en zonas adyacentes a los ríos Cauca, Cali y a los canales Interceptor Sur y Oriental

    Cambios de cobertura/uso del suelo en una porción de la Zona de Transición Mexicana de Montaña

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    La Porción Surponiente del Estado de México (PSEM) se ubica en la Zona de Transición Mexicana de Montaña. Las comunidades forestales que predominan en este territorio son bosques de pino (Pinus spp.), encino (Quercus spp.), mixtos (Pinus spp. - Quercus spp. y Quercus spp. - Pinus spp.), mesófilo de montaña y tropical caducifolio, los cuales están siendo modificados por la influencia de procesos antropogénicos. Este estudio presenta el análisis de los cambios de cobertura y uso del suelo ocurridos entre 1989 y 2009 en la PSEM, a través de la interpretación de imágenes de satélite (Landsat TM), que en complemento con la aplicación del algoritmo máxima verosimilitud permitieron la construcción de mapas temáticos de uso de suelo y vegetación, los cuales fueron evaluados para conocer su confiabilidad temática. A partir de la sobreposición de estos mapas se elaboró una matriz de cambios que comprende la superficie de las coberturas y usos del suelo para cada año y con base en esta se determinaron las tasas de cambio. Los resultados obtenidos demuestran que la cobertura del bosque disminuyó considerablemente, es decir, se eliminaron 19 262 ha, las cuales fueron ocupadas por las categorías cuerpos de agua (105 ha), agropecuario (19 113 ha), asentamientos humanos (39 ha) y agricultura tecnificada controlada (5 ha). La superficie deforestada es resultado del establecimiento y la práctica de actividades relacionadas con la agricultura y ganadería

    Tendencias y retos de la geografía en América Latina en el siglo XXI: una perspectiva desde el VII CGAL

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    Su estructura contempla siete capítulos: en el primero denominado Origen y devenir histórico del Coloquio Geográfico sobre América Latina de la Facultad de Geografía de la UAEM de los autores Carlos Reyes Torres, Agustín Olmos Cruz y Fernando Carreto Bernal, integrantes del Cuerpo Académico en Educación y Enseñanza de la Geografía, da cuenta del origen de los Coloquios Geográficos de AL, estableciendo sus etapas de desarrollo desde 1993 al 2014, caracterizando sus comités organizadores, ejes temáticos, así como la representación de los ponentes de las instituciones y países participantes. La relevancia de estos estudios radica en la recuperación de la historia de los eventos para fomentar la identidad y sentido de pertenencia con la disciplina y con la institución.El presente libro intitulado Tendencias y retos de la geografía en América Latina en el siglo XXI: una perspectiva desde el VII CGAL, es un producto derivado del 7° Coloquio Geográfico sobre América Latina, celebrado en desde hace ya dos décadas en la Facultad de Geografía de la Universidad Autónoma del Estado de México, convocando con el eje temático sobre “Las Tendencias y retos de la Geografía en América Latina en el siglo XXI”Universidad Autónoma del Estado de México Facultad de Geografí

    Clinical practice guideline for surgical antimicrobial prophylaxis

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    La infección del sitio quirúrgico (ISQ) es una de las principales causas de infecciones asociadas a la atención en salud (IAAS), con un impacto significativo en la mortalidad y morbilidad del paciente quirúrgico, así como en los costos asociados a la atención en salud. El adecuado uso de la profilaxis quirúrgica antimicrobiana es un aspecto fundamental en la reducción del riesgo de ISQ, dado que su utilización inapropiada o indiscriminada puede representar un riesgo para los pacientes y contribuir al desarrollo de resistencia a los antimicrobianos, por lo que resulta de importancia generar directrices que permitan orientar el uso adecuado de antimicrobianos en la profilaxis del paciente quirúrgico, con el objetivo de obtener mejores desenlaces clínicos y propender por un uso racional de antibióticos. La presente guía contiene recomendaciones para profilaxis antibiótica de pacientes sometidos a procedimiento quirúrgico, basadas en la evidencia, realizadas mediante el proceso de adaptación de guías de práctica clínica para el contexto colombiano.Q4Pacientes sometidos a Profilaxis quirúrgica antimicrobianaSurgical site infection (SSI) is one of the main causes of healthcare associated infections (HAI), with a significant impact on the mortality and morbidity of the surgi-cal patient, as well as on the costs associated with health care. The adequate use of surgical antimicrobial prophylaxis being a fundamental aspect in reducing the risk of SSI, taking into account that the inappropriate or indiscriminate use of antibiotics in surgical prophylaxis may represent a risk for patients and contribute to the development of antimicrobial resistance, so it is important to generate guidelines that guide the appropriate antimicrobial prophylaxis in the surgical patient, with the aim of obtaining better clinical outcomes and promoting a rational use of antibiotics. This guide contains recommendations for antibiotic prophylaxis in patients undergoing a surgical procedure, based on evidence, carried out through the process of adapting clinical practice guidelines for the Colombian context.https://orcid.org/0000-0002-5392-7083https://orcid.org/0000-0003-2568-4667Revista Nacional - IndexadaCN

    Healthcare workers hospitalized due to COVID-19 have no higher risk of death than general population. Data from the Spanish SEMI-COVID-19 Registry

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    Aim To determine whether healthcare workers (HCW) hospitalized in Spain due to COVID-19 have a worse prognosis than non-healthcare workers (NHCW). Methods Observational cohort study based on the SEMI-COVID-19 Registry, a nationwide registry that collects sociodemographic, clinical, laboratory, and treatment data on patients hospitalised with COVID-19 in Spain. Patients aged 20-65 years were selected. A multivariate logistic regression model was performed to identify factors associated with mortality. Results As of 22 May 2020, 4393 patients were included, of whom 419 (9.5%) were HCW. Median (interquartile range) age of HCW was 52 (15) years and 62.4% were women. Prevalence of comorbidities and severe radiological findings upon admission were less frequent in HCW. There were no difference in need of respiratory support and admission to intensive care unit, but occurrence of sepsis and in-hospital mortality was lower in HCW (1.7% vs. 3.9%; p = 0.024 and 0.7% vs. 4.8%; p<0.001 respectively). Age, male sex and comorbidity, were independently associated with higher in-hospital mortality and healthcare working with lower mortality (OR 0.211, 95%CI 0.067-0.667, p = 0.008). 30-days survival was higher in HCW (0.968 vs. 0.851 p<0.001). Conclusions Hospitalized COVID-19 HCW had fewer comorbidities and a better prognosis than NHCW. Our results suggest that professional exposure to COVID-19 in HCW does not carry more clinical severity nor mortality

    Role of age and comorbidities in mortality of patients with infective endocarditis

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    [Purpose]: The aim of this study was to analyse the characteristics of patients with IE in three groups of age and to assess the ability of age and the Charlson Comorbidity Index (CCI) to predict mortality. [Methods]: Prospective cohort study of all patients with IE included in the GAMES Spanish database between 2008 and 2015.Patients were stratified into three age groups:<65 years,65 to 80 years,and ≥ 80 years.The area under the receiver-operating characteristic (AUROC) curve was calculated to quantify the diagnostic accuracy of the CCI to predict mortality risk. [Results]: A total of 3120 patients with IE (1327 < 65 years;1291 65-80 years;502 ≥ 80 years) were enrolled.Fever and heart failure were the most common presentations of IE, with no differences among age groups.Patients ≥80 years who underwent surgery were significantly lower compared with other age groups (14.3%,65 years; 20.5%,65-79 years; 31.3%,≥80 years). In-hospital mortality was lower in the <65-year group (20.3%,<65 years;30.1%,65-79 years;34.7%,≥80 years;p < 0.001) as well as 1-year mortality (3.2%, <65 years; 5.5%, 65-80 years;7.6%,≥80 years; p = 0.003).Independent predictors of mortality were age ≥ 80 years (hazard ratio [HR]:2.78;95% confidence interval [CI]:2.32–3.34), CCI ≥ 3 (HR:1.62; 95% CI:1.39–1.88),and non-performed surgery (HR:1.64;95% CI:11.16–1.58).When the three age groups were compared,the AUROC curve for CCI was significantly larger for patients aged <65 years(p < 0.001) for both in-hospital and 1-year mortality. [Conclusion]: There were no differences in the clinical presentation of IE between the groups. Age ≥ 80 years, high comorbidity (measured by CCI),and non-performance of surgery were independent predictors of mortality in patients with IE.CCI could help to identify those patients with IE and surgical indication who present a lower risk of in-hospital and 1-year mortality after surgery, especially in the <65-year group

    A search for ultra-high-energy photons at the Pierre Auger Observatory exploiting air-shower universality

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    The Pierre Auger Observatory is the most sensitive detector to primary photons with energies above ∼0.2 EeV. It measures extensive air showers using a hybrid technique that combines a fluorescence detector (FD) with a ground array of particle detectors (SD). The signatures of a photon-induced air shower are a larger atmospheric depth at the shower maximum (Xmax_{max}) and a steeper lateral distribution function, along with a lower number of muons with respect to the bulk of hadron-induced background. Using observables measured by the FD and SD, three photon searches in different energy bands are performed. In particular, between threshold energies of 1-10 EeV, a new analysis technique has been developed by combining the FD-based measurement of Xmax_{max} with the SD signal through a parameter related to its muon content, derived from the universality of the air showers. This technique has led to a better photon/hadron separation and, consequently, to a higher search sensitivity, resulting in a tighter upper limit than before. The outcome of this new analysis is presented here, along with previous results in the energy ranges below 1 EeV and above 10 EeV. From the data collected by the Pierre Auger Observatory in about 15 years of operation, the most stringent constraints on the fraction of photons in the cosmic flux are set over almost three decades in energy

    Study on multi-ELVES in the Pierre Auger Observatory

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    Since 2013, the four sites of the Fluorescence Detector (FD) of the Pierre Auger Observatory record ELVES with a dedicated trigger. These UV light emissions are correlated to distant lightning strikes. The length of recorded traces has been increased from 100 μs (2013), to 300 μs (2014-16), to 900 μs (2017-present), to progressively extend the observation of the light emission towards the vertical of the causative lightning and beyond. A large fraction of the observed events shows double ELVES within the time window, and, in some cases, even more complex structures are observed. The nature of the multi-ELVES is not completely understood but may be related to the different types of lightning in which they are originated. For example, it is known that Narrow Bipolar Events can produce double ELVES, and Energetic In-cloud Pulses, occurring between the main negative and upper positive charge layer of clouds, can induce double and even quadruple ELVES in the ionosphere. This report shows the seasonal and daily dependence of the time gap, amplitude ratio, and correlation between the pulse widths of the peaks in a sample of 1000+ multi-ELVES events recorded during the period 2014-20. The events have been compared with data from other satellite and ground-based sensing devices to study the correlation of their properties with lightning observables such as altitude and polarity

    Outreach activities at the Pierre Auger Observatory

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