Papers by Juan Carlos Barcia Barrera
Endothelium, 2005
Endothelial dysfunction (ED), which is often evaluated by flowmediated vasodilation (FMV) in the ... more Endothelial dysfunction (ED), which is often evaluated by flowmediated vasodilation (FMV) in the brachial artery, has been postulated as a predictor of cardiac events. Although the upper and forearm location of the occlusion device have been used for FMV evaluation, currently there is no consensus whether they provide the same information. The main goal of this study was to evaluate if both techniques have the same accuracy to differentiate subjects with and without cardiovascular risk factors (CRFs). A crosssectional study in 124 subjects was performed. The volunteers were divided in two groups: 62 subjects (20 women and 42 men) with at least one CRF and 62 (20 women and 42 men) healthy subjects without CRFs. FMV measurements using the cuff in the upper arm and forearm with intervals of 30 min were taken. In all subjects, %FMV with the cuff located in the upper arm was 10.13 ± 4.5 and 9.8 ± 4.1 with the cuff located below the elbow. In healthy subjects without CRFs the %FMV in the upper arm was 12.19 ± 4.0 versus 12.31 ± 3.4 in the upper forearm, in CRF subjects it was 8.08 ± 4.0 vs 7.29 ± 3.2., respectively. FMV was not affected by the location of the cuff in maintaining the test ability and accuracy to differentiate subjects with and without CRFs.
Remote Sensing, 2020
Current estimates of CO2 emissions from forest degradation are generally based on insufficient in... more Current estimates of CO2 emissions from forest degradation are generally based on insufficient information and are characterized by high uncertainty, while a global definition of ‘forest degradation’ is currently being discussed in the scientific arena. This study proposes an automated approach to monitor degradation using a Landsat time series. The methodology was developed using the Google Earth Engine (GEE) and applied in a pine forest area of the Dominican Republic. Land cover change mapping was conducted using the random forest (RF) algorithm and resulted in a cumulative overall accuracy of 92.8%. Forest degradation was mapped with a 70.7% user accuracy and a 91.3% producer accuracy. Estimates of the degraded area had a margin of error of 10.8%. A number of 344 Landsat collections, corresponding to the period from 1990 to 2018, were used in the analysis. Additionally, 51 sample plots from a forest inventory were used. The carbon stocks and emissions from forest degradation were...
Colombia Medica, 2012
Objective: to quantify placenta-specific RNA in plasma of women carrying foetuses with intrauteri... more Objective: to quantify placenta-specific RNA in plasma of women carrying foetuses with intrauterine growth restriction and pregnant women with normal pregnancies. Materials and methods: 8 pregnant women with foetuses with intrauterine growth restriction were studied as well as 18 women with uncomplicated pregnancies in the third pregnancy trimester. Total free RNA was quantified in maternal plasma by spectrophotometry and the gene expression of hPL (Human Placental Lactogen) at the messenger RNA level through technical Real Time-Chain Reaction Polymerase. Results: plasma RNA of fetoplacental origin was successfully detected in 100% of pregnant women. There were no statistically significant differences between the values of total RNA extracted from plasma (p = 0.5975) nor in the messenger RNA expression of hPL gene (p = 0.5785) between cases and controls. Conclusion: messenger RNA of fetoplacental origin can be detected in maternal plasma during pregnancy.
A critical aspect of predicting soil organic carbon (SOC) concentrations is the lack of available... more A critical aspect of predicting soil organic carbon (SOC) concentrations is the lack of available soil information; where information on soil characteristics is available, it is usually focused on regions of high agricultural interest. To date, in Chile, a large proportion of the SOC data have been collected in areas of intensive agricultural or forestry use; however, vast areas beyond these forms of land use have few or no soil data available. Here we present a new SOC database for the country, which is the result of an unprecedented national effort under the framework of the Global Soil Partnership. This partnership has helped build the largest database of SOC to date in Chile, named the Chilean Soil Organic Carbon database (CHLSOC), comprising 13 612 data points compiled from numerous sources, including unpublished and difficult-to-access data. The database will allow users to fill spatial gaps where no SOC estimates were publicly available previously. Presented values of SOC range from 6 × 10 −5 % to 83.3 %, reflecting the variety of ecosystems that exist in Chile. The database has the potential to inform and test current models that predict SOC stocks and dynamics at larger spatial scales, thus enabling benefits from the richness of geochemical, topographic and climatic variability in Chile.
Nuevo Foro Penal, 2015
Para justificar una política criminal expansionista se apela a que la misma responde al clamor po... more Para justificar una política criminal expansionista se apela a que la misma responde al clamor popular, a una demanda social de seguridad. Sin embargo, diversos esfuerzos académicos han rebatido tal hipótesis. Con amplia investigación empírica se ha demostrado que no existe una relación directa entre los deseos punitivos de la sociedad y la actual política criminal expansiva y que la ciudadanía no es un bloque monolítico de actitudes punitivas. Tal investigación no se ha desarrollado en Colombia, a pesar de que en repetidas ocasiones el ejercicio del poder punitivo del Estado se ha visto ampliado para responder precisamente a un supuesto llamado de la sociedad, a la “mano dura” que la misma exige frente al delito. El artículo enseña parte de los resultados de una investigación que propone un acercamiento empírico cuantitativo a la caracterización de las actitudes de los colombianos frente al crimen y al castigo mediante la elaboración de un estudio piloto sobre el referido tema en l...
Nuevo Foro Penal, 2013
El artículo estudia la posibilidad de utilizar el concepto de populismo punitivo para catalogar l... more El artículo estudia la posibilidad de utilizar el concepto de populismo punitivo para catalogar la relación entre las actitudes punitivas de los ciudadanos y la política criminal de corte expansivo en Colombia. Para lo anterior define como ruta metodológica un acercamiento a la cuestión en tres etapas. Inicialmente, define el concepto de populismo punitivo situándolo al interior de la denominada cultura del control. Posteriormente, comenta las dificultades presentadas al importar estos conceptos en nuestro contexto. Finalmente, se plantea la necesidad de crear un concepto que capte la especificidad de la cultura política colombiana, utilizando un concepto denominado populismo hobbesiano.
Applied Sciences, 2017
Soil spectroscopy is known as a rapid and cost-effective method for predicting soil properties fr... more Soil spectroscopy is known as a rapid and cost-effective method for predicting soil properties from spectral data. The objective of this work was to build a statistical model to predict soil carbon content from spectral data by partial least squares regression using a limited number of soil samples. Soil samples were collected from two soil orders (Andisol and Ultisol), where the dominant land cover is native Nothofagus forest. Total carbon was analyzed in the laboratory and samples were scanned using a spectroradiometer. We found evidence that the reflectance was influenced by soil carbon content, which is consistent with the literature. However, the reflectance was not useful for building an appropriate regression model. Thus, we report here intriguing results obtained in the calibration process that can be confusing and misinterpreted. For instance, using the Savitzky-Golay filter for pre-processing spectral data, we obtained R 2 = 0.82 and root-mean-squared error (RMSE) = 0.61% in model calibration. However, despite these values being comparable with those of other similar studies, in the cross-validation procedure, the data showed an unusual behavior that leads to the conclusion that the model overfits the data. This indicates that the model should not be used on unobserved data.
Creaciones J&D es una empresa de confecciones creada en al ano 2001 por su actual gerente gen... more Creaciones J&D es una empresa de confecciones creada en al ano 2001 por su actual gerente general, gracias a la informacion suministrada por el gerente se lleva a cabo el desarrollo del Plan Exportador de la empresa en donde se tomo en cuenta una serie de variables para identificar el segmento de mercado y tipo de cliente al que se va a exportar. Por medio del uso de una serie de variables analizadas en el desarrollo del proceso para el inicio de una actividad de exportacion ayudamos a esta PYME a facilitar su proceso de internacionalizacion a mediano plazo, dependiendo de la experiencia y resultados en el mercado objetivo a largo plazo sera probable vender los productos comercialmente por medio de marca y prestigio. De esta forma hemos desarrollado este trabajo teniendo en cuenta estos factores, para poder lograr las metas de exportacion, la empresa debe generar un plan de trabajo para que en tres anos se encuentre exportando y por ello se plantea actividades a realizar para continuar explorando los mercados que hacen parte de la CAN. La recomendacion es concentrarse en la ventaja competitiva del diseno y calidad del producto, en cuanto a su capacidad productiva, es poder garantizar los tiempos de entrega usando empresas satelites y demas medios que maximicen utilidades y optimicen tiempo, para tener una capacidad de respuesta a la altura de los mercados internacionales.
Energetica, Sep 15, 2011
Sin embargo, las estaciones secas ocasionan que el riesgo de incumplir esos contratos crezca, pue... more Sin embargo, las estaciones secas ocasionan que el riesgo de incumplir esos contratos crezca, pues la generación hidráulica puede resultar insuficiente. En caso de no tener ninguna alternativa tecnológica ante una baja hidrología, un agente podría verse obligado a cumplir sus obligaciones contractuales comprando energía en Bolsa, lo cual precisamente en los períodos secos es mucho más costoso. A su vez, la elevada fluctuación en el Precio de Bolsa, o Volatilidad, puede afectar adversamente los flujos de caja de los
Homeopatia Mex, Oct 1, 2001
Revista Colombiana De Cardiologia, 2012
Revista Colombiana De Cirugia, Dec 1, 2011
Iliocovesical fistulas are infrequent complications of abdominal aortic aneurysms (AAA). We repor... more Iliocovesical fistulas are infrequent complications of abdominal aortic aneurysms (AAA). We report the case of a 76 year-old male with a contained ruptured aneurysm of the iliac to the urinary bladder. Complaints on presentation were abdominal pain and hematuria; suspected iliacovesical fistula was reported on a computed tomography (CT) scan, which was confirmed during laparotomy. The patient died 20 days after the procedure due to mixed distributive septic shock.
Folia Entomologica Mexicana, 1990
Uploads
Papers by Juan Carlos Barcia Barrera