Usability Engineering and PPGIS - Towards a Learning-improving Cycle

July 21 - 2

CO, Pb++ and SO2 effects on L-type calcium channel and action potential in human atrial myocytes. In silico study

La exposición a contaminantes atmosféricos, como el monóxido de carbono (CO), plomo (Pb++) y dióxido de azufre (SO2), promueve la aparición de enfermedades cardiovasculares. Estudios experimentales han demostrado que el CO, el Pb++ y el SO2 bloquean los canales de calcio tipo L, disminuyendo la corriente de calcio (ICaL) y la duración del potencial de acción (APD), favoreciendo el inicio de arritmias auriculares. El objetivo es estudiar los efectos del CO, Pb++ y SO2 a diferentes concentraciones, sobre ICaL y el potencial de acción auricular mediante simulación computacional. Para ello, se desarrollaron modelos matemáticos de los efectos de los contaminantes atmosféricos sobre el canal de calcio auricular tipo L y se incorporaron en un modelo matemático de células auriculares humanas. Los resultados sugieren que el CO, el Pb++ y el SO2, bloquean la corriente ICaL en una fracción que aumenta a medida que aumenta, la concentración, generando un acortamiento del APD. Estos resultados son consistentes con estudios experimentales. El efecto combinado de los tres contaminantes atmosféricos generó un acortamiento del APD, lo cual es considerado un efecto pro-arrítmico.Exposure to air pollutants like carbon monoxide (CO), lead (Pb++) and sulfur dioxide (SO2) promotes the occurrence of cardiovascular diseases. Experimental studies have shown that CO, Pb++ and SO2 block L-type calcium channels, reducing the calcium current (ICaL) and the action potential duration (APD), which favors the initiation of atrial arrhythmias. The goal is to study the effects of CO, Pb++ and SO2 at different concentrations on ICaL and action potential using computational simulation. For this purpose, models of the effects of the air pollutants on the atrial L-type calcium channel were developed and were incorporated into a mathematical model of a human atrial cell. The results suggest that CO, Pb++ and SO2 block the ICaL current in a fraction that increases along with the concentration, generating an APD shortening. These results are consistent with experimental studies. The combined effect of the three air pollutants produced an APD shortening, which is considered to be a pro-arrhythmic effect

Oportunidad para tener nuevas experiencias

La Ingeniera Catalina Tobón atendió una entrevista con el Doctor en Ingeniería Edison Valencia Díaz, miembro del Comité Editorial de la Revista Ingeniería Biomédica

Financing of residential rooftop photovoltaic projects under a net metering policy framework: the case of the colombian caribbean region

The inclusion of photovoltaic energy in the Colombian energy matrix has had several difficulties due to the lack of energy policies and regulations in renewable energy projects. The lack of government support with subsidies that extend the coverage of PV energy projects in residential areas has made the collection of funds more challenging. This paper presents a techno-economic analysis for the implementation of grid-connected photovoltaic projects on the roofs of residential areas, under the net metering policy framework. For the profitability analysis, the discounted cash flow (DCF) method was used. The revenues were obtained from the forecasts of the electrical power production of the PV system, based on the characteristics of the Colombian Caribbean Region. For this purpose, the meteorological data (2013-2017) of this region were used as an input for the calculation of the economic benefits that can be achieved with the implementation of PV systems. Based on the technical sizing and economic assumptions, it was proved that the DCF method allows to accurately determine the optimal debt ratio. After evaluating the three scenarios proposed, it was demonstrated that profitability and self-sustainability, with investment from creditors, is obtained from the implementation of PV systems of at least 3 kWp

Anthropometric characteristics of elite paddle players: Pilot study

El objetivo de este estudio fue describir las características antropométricas, la composición corporal y el somatotipo de una muestra internacional de jugadores de pádel de alto nivel de ambos sexos. En el estudio participaron 29 jugadores (15 varones y 14 mujeres) de categoría absoluta. Un total de 16 variables antropométricas fueron evaluadas. Se encontraron diferencias entre sexos en las variables masa, talla e IMC (p<0,001); en los pliegues tricipital, muslo, pierna (p<0,001) y en el sumatorio de 6 pliegues; en los perímetros brazo, muslo (p<0,001) y pierna (p<0,03); y en todos los diámetros analizados (p<0,001). Asimismo se encontraron diferencias en los componentes endomórfico (p<0,01), mesomórfico (p<0,001) y ectomórfico (p<0,05) del somatotipo. Los jugadores presentan un somatotipo mesomórfico-endomórfico y las jugadoras endo-mesomórfico. Esta investigación aporta datos biotipológicos actualizados de referencia para el pádel de élitePaddle is one of the racket sports that has grown the most in recent years. However, there are few or very limited studies that address the biotype of this discipline, especially in the elite paddle. The aim was to describe the anthropometric characteristics, body composition and somatotype of an international sample of high level paddle players. 29 subjects national top level (15 male and 14 female) participated in this study. 16 anthropometric variables were evaluated. Differences were found between sexes in the variables weight, height and BMI (p <0.001); in triceps, thigh and leg folds (p <0.001); in the arm, thigh (p <0.001) and leg (p <0.03) perimeters; and in all diameters analysed (p <0.001). Differences were also found between men and women in the endomorphic (p <0.01), mesomorphic (p <0.001) and ectomorphic (p <0.05) components of the somatotype. Male players present a mesomorphic-endomorphic somatotype while female players are preferably endo-mesomorphic. This research provides up-to-date reference data for somatotype in elite paddle playersInstituto de Estudios Altoaragoneses por el proyecto “Análisis de las demandas fisiológicas del pádel de competición: estudio de marcadores asociados al rendimiento físico-deportivo.

Short communication: Application of site‐level assessment of governance and equity (sage) methodology to a candidate oecm: AndakÍ municipal natural park, caquetÁ, colombia.

Governance is a fundamental aspect and precondition for conservation strategies, such as protected areas or OECMs. A methodology for Site-level Assessment of Governance and Equity (SAGE) has been proposed by IUCN to explore different aspects of governance, based on ten principles. This article describes the application of SAGE to a candidate OECM for what we believe is the first time: the Andakí Municipal Natural Park in the Amazon region of Colombia. The application of SAGE generated useful insights into different aspects of governance, including the importance of good communication and recognising and respecting the rights and responsibilities of different actors. Based on this experience, we believe that the SAGE methodology could be a useful tool not only to identify priorities for improving governance, but also to assess governance and equity in order to evaluate if an area meets the criteria for an OECM that it is governed and managed to achieve sustained and effective contributions to in situ conservation of biodiversity, associated ecosystem functions and services, and cultural, spiritual, socio-economic and other locally relevant values. © 2021, IUCN - International Union for the Conservation of Nature. All rights reserved.This process was made possible with the support of: a) the Local Protected Areas Regional Project implemented by Deutsche Gesellschaft f?r Internationale Zusammenarbeit (GIZ) GmbH, ICLEI ? Local Governments for Sustainability and the International Union for Conservation of Nature (IUCN); Environment ministries in Brazil, Colombia, Ecuador and Peru; commissioned by the German Federal Ministry for the Environment, Nature Protection and Nuclear Safety; b) the project adaptation of the OECM criteria to the Colombian context supported by PPD-GEF-PNUD, and implemented by Resnatur, Instituto Humboldt, Fundaci?n Natura and the Local Protected Areas Project; and c) the EUROCLIMA+ programme supported by Expertise France, GIZ and the International Institute for the Environment and Development (IIED); and d) Thora Amend, Vice Chair, IUCN World Commission on Protected Areas (thematic area: Governance)

Chemical and organic fertilization of tomatoe in Eastern Antioquia, Colombia

En 1980 y 1981 el ICA, en colaboración con la Secretaría de Agricultura de Antioquia, adelantó 18 ensayos de tomate chonto en fincas de agricultores, ubicadas en Marinilla y el Peñol (Oriente Antioqueño). De los ensayos, 7 se perdieron por causa de nematodos y enfermedades como Phoma sp., Xanthoma sp., Phytophthora spp. y Fusarium spp., las cuales hicieron disminuir sus rendimientos. El objetivo era ajustar recomendaciones de fertilizantes químicos y orgánicos para este cultivo, bajo los tres sistemas de siembra más usados en la zona, cuyos suelos son muy fuertemente ácidos, con alto contenido de Al intercambiable y de muy baja fertilidad. En ningún sistema de siembra los agricultores usan encalamiento. Según los resultados obtenidos es aconsejable reducir las dosis de fertilizantes antes recomendadas, y aplicar sólo una fórmula de 50 kg/ha de N, 150 kg/ha de P y 5 t/ha de gallinaza. Las enfermedades del cultivo están limitando más seriamente el rendimiento que la misma fertilización. Antes de este trabajo, las recomendaciones de fertilizantes se daban bajo el supuesto de obtener rendimientos de 40 t/ha y basados en la extracción de nutrientes que la cosecha hace del suelo. La baja calidad de los suelos, la ausencia de riego, la alta pérdida en desarrollo vegetativo y la pudrición por enfermedades hacen muy costoso, riesgoso y poco rentable usar, por ahora, recomendaciones que casi doblaban lo obtenido en este trabajo. Se espera estudiar comportamiento de variedades, acidez del suelo, niveles y métodos de aplicación de cal, captación de residuos de fertilizante químico y orgánico para cultivos en relevo y buscar mayor aprovechamiento de P y K cuando su aplicación pueda aumentarse, lo cual parece necesario; pero antes debe solucionarse el limitante de las enfermedades y de la rotación de cultivos en tomate.Eighteen field experiments were conducted by the Institute of Colombian Agriculture during 1980 and 1981 to study the response of tomatoe to chemical and organic fertilization under farm conditions in Marinilla and Penol, two small towns located in the eastern part of Antioquia, Colombia. The purpose of the study was to precise chemical and organic fertilizers-recommendations to crop the "chonto" tomatoe variety, taking into account the three most used tomatoe cropping-systems in this area. Soils in this region are characterized by high acidity, high content of interchangeable aluminium and low fertility. Farmers do not use lime. Although, seven experiments were lost due to the incidence of nematoda and fungi, the results of this investigation indicate the need to reduce the levels of fertilization and to just apply 50 kg of N per hectare, 150 kg of P and 5 tons of hen duna. A higher dosage is not recommended since the production limiting factors are tomatoe diseases. It is important to study this problem first, and then to identify and solve other limiting factors like soil acidity, liming dosages and methods of applications.Tomate-Solanum lycopersicu

Atrial proarrhythmic effect of lead as one of the PM10 metal components of air pollution. An in-silico study

[EN] Particulate matter (PM) is considered the most severe environmental pollution problem due to its serious effects on human health associated with an increased risk of cardiovascular morbidity and mortality. In this work, a physicochemical characterization of PM10 from the city of Medellin was developed. The results evince that lead (Pb) is one of the most abundant elements since it is present in all analyzed samples. Therefore, Pb was chosen to perform an in-silico study to assess its effects on atrial arrhythmias generation. For this purpose, we developed a model representing the Pb2+ blocking effect on the L-type calcium channel. This formulation was incorporated in a human atrial cell mathematical model and in 2D and 3D models of human atria. The simulations showed a proarrhythmic effect at high Pb2+ concentrations, through shortening of action potential duration inducing the generation of reentrant activity and atrial flutter. The results contribute to the knowledge about the cardiac physiopathological processes, triggered by lead as one of the main PM10 metal components of air pollution, that yields the generation of arrhythmias.This work was supported by Ministerio de Ciencia, Tecnologi a e Innovacion MINCIENCIAS from Colombia, through grant No. 120677757994; and by the Direccion General de Politica Cientifica de la Generalitat Valenciana PROMETEO/2020/043.Palacio, LC.; Pachajoa, DC.; Durango-Giraldo, G.; Zapata-Hernández, C.; Ugarte, JP.; Saiz Rodríguez, FJ.; Buitrago-Sierra, R.... (2021). Atrial proarrhythmic effect of lead as one of the PM10 metal components of air pollution. An in-silico study. PLoS ONE. 16(10):1-17. https://doi.org/10.1371/journal.pone.0258313S117161

Tractography of the Spider Monkey (\u3cem\u3eAteles geoffroyi\u3c/em\u3e) Corpus Callosum Using Diffusion Tensor Magnetic Resonance Imaging

The objective of this research was to describe the organization, connectivity and microstructure of the corpus callosum of the spider monkey (Ateles geoffroyi). Non-invasive magnetic resonance imaging and diffusion-tensor imaging were obtained from three subjects using a 3T Philips scanner. We hypothesized that the arrangement of fibers in spider monkeys would be similar to that observed in other non-human primates. A repeated measure (n = 3) of fractional anisotropy values was obtained of each subject and for each callosal subdivision. Measurements of the diffusion properties of corpus callosum fibers exhibited a similar pattern to those reported in the literature for humans and chimpanzees. No statistical difference was reached when comparing this parameter between the different CC regions (p = 0.066). The highest fractional anisotropy values corresponded to regions projecting from the corpus callosum to the posterior cortical association areas, premotor and supplementary motor cortices. The lowest fractional anisotropy corresponded to projections to motor and sensory cortical areas. Analyses indicated that approximately 57% of the fibers projects to the frontal cortex and 43% to the post-central cortex. While this study had a small sample size, the results provided important information concerning the organization of the corpus callosum in spider monkeys