64 research outputs found

    14- #1027 EVALUACIÓN DE LA EFECTIVIDAD DE UN IMPUESTO AL CARBONO EN UNA CADENA DE SUMINISTRO DE CEMENTO

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    En este trabajo abordamos el problema de la evaluación de la efectividad de los impuestos al carbono como mecanismo para promover la incorporación de procesos productivos más sostenibles. En particular estudiamos el efecto de los impuestos al carbono sobre las emisiones totales de CO2 de una cadena de suministro de cemento. Para cuantificar este efecto se proponen dos formulaciones de programación lineal entera mixta que explícitamente incorporan esquemas de impuestos al carbono, con las cuales se evalúan diferentes tasas impositivas, con el fin de determinar el valor a partir del cual la empresa obtiene un beneficio económico por reducir sus emisiones de CO2. En este estudio concentramos nuestra atención en la industria del cemento debido a tres razones fundamentales: la alta demanda de este producto a nivel mundial, la gran cantidad de energía necesaria para su producción, y los altos niveles de emisiones de gases de efecto invernadero atribuibles a este proceso productivo. Para llevar a cabo este estudio se construyó una instancia de prueba de tamaño realista a partir de información pública disponible sobre la industria del cemento. Los resultados obtenidos luego de llevar a cabo un experimento computacional extenso indican que tasas impositivas entre 15 y 150 dólares por tonelada emitida de CO2 inducen una reducción en las emisiones totales entre el 11 y el 24%

    ARABIDOPSIS DEHISCENCE ZONE POLYGALACTURONASE 1 (ADPG1) releases latent defense signals in stems with reduced lignin content

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    There is considerable interest in engineering plant cell wall components, particularly lignin, to improve forage quality and biomass properties for processing to fuels and bioproducts. However, modifying lignin content and/or composition in transgenic plants through down-regulation of lignin biosynthetic enzymes can induce expression of defense response genes in the absence of biotic or abiotic stress. Arabidopsis thaliana lines with altered lignin through down-regulation of hydroxycinnamoyl CoA:shikimate/quinate hydroxycinnamoyl transferase (HCT) or loss of function of cinnamoyl CoA reductase 1 (CCR1) express a suite of pathogenesis-related (PR) protein genes. The plants also exhibit extensive cell wall remodeling associated with induction of multiple cell wall-degrading enzymes, a process which renders the corresponding biomass a substrate for growth of the cellulolytic thermophile Caldicellulosiruptor bescii lacking a functional pectinase gene cluster. The cell wall remodeling also results in the release of size- and charge-heterogeneous pectic oligosaccharide elicitors of PR gene expression. Genetic analysis shows that both in planta PR gene expression and release of elicitors are the result of ectopic expression in xylem of the gene ARABIDOPSIS DEHISCENCE ZONE POLYGALACTURONASE 1 (ADPG1), which is normally expressed during anther and silique dehiscence. These data highlight the importance of pectin in cell wall integrity and the value of lignin modification as a tool to interrogate the informational content of plant cell walls

    La justicia transicional en los acuerdos de la Habana

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    Respondiendo a la apuesta y al compromiso de EAFIT con el esfuerzo actual de terminación negociada del conflicto armado interno colombiano, desde septiembre del año pasado el Departamento de Gobierno y Ciencias Políticas de la Escuela de Humanidades de la Universidad emprendió el proyecto de publicación de una serie de Cuadernos de Trabajo como una aproximación académica y cívico-política preliminar al proceso de paz y a los acuerdos que en el transcurso del mismo han ido suscribiendo paulatinamente el Gobierno Nacional y la guerrilla de las FARC. A esta iniciativa ha querido contribuir la Escuela de Derecho de la Universidad mediante la elaboración del Cuaderno de Trabajo relativo al “Acuerdo sobre las Víctimas del Conflicto” dado a conocer a la opinión pública el pasado mes de diciembre. Este acuerdo crea el así llamado “Sistema Integral de Verdad, Justicia, Reparación y No Repetición” (SIVJRNR) y ha sido considerado casi unánimemente como el punto de inflexión o de “no retorno” en el intento de alcanzar un acuerdo de paz definitivo dada la enorme dificultad que supuso convenir un sistema de justicia transicional. En sintonía con la finalidad que persigue el proyecto, los aportes realizados por los profesores de las distintas áreas de la Escuela que participaron en la confección de este Cuaderno, no sólo buscan contribuir con el análisis teórico y/o académico de los distintos componentes del sistema de justicia transicional pactado, sino también con la divulgación y la comprensión del mismo y de sus implicaciones tanto por parte de los distintos sectores de la sociedad como por parte de la población en general; así mismo, procuran establecer un canal de comunicación efectivo con quienes tienen en sus manos la implementación jurídica del acuerdo. Una vez más, agradecemos profundamente a la Asociación Nacional de Empresarios (Andi) y la Fundación para el Progreso de Antioquia (Proantioquia) por la colaboración y el apoyo ofrecidos para la realización del presente Cuaderno y para la satisfactoria materialización de este proyecto en su conjunto

    Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isolated rabbit heart

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    [EN] A study has been made of the effect of chronic exercise on myocardial electrophysiological heterogeneity and stability, as well as of the role of cholinergic neurons in these changes. Determinations in hearts from untrained and trained rabbits on a treadmill were performed. The hearts were isolated and perfused. A pacing electrode and a recording multielectrode were located in the left ventricle. The parameters determined during induced VF, before and after atropine (1 mu M), were: fibrillatory cycle length (VV), ventricular functional refractory period (FRPVF), normalized energy (NE) of the fibrillatory signal and its coefficient of variation (CV), and electrical ventricular activation complexity, as an approach to myocardial heterogeneity and stability. The VV interval was longer in the trained group than in the control group both prior to atropine (78 +/- 10 vs. 68 +/- 10 ms) and after atropine (76 +/- 8 vs. 67 +/- 10 ms). Likewise, FRPVF was longer in the trained group than in the control group both prior to and after atropine (53 +/- 8 vs. 42 +/- 7 ms and 50 +/- 6 vs. 40 +/- 6 ms, respectively), and atropine did not modify FRPVF. The CV of FRPVF was lower in the trained group than in the control group prior to atropine (12.5 +/- 1.5% vs. 15.1 +/- 3.8%) and, decreased after atropine (15.1 +/- 3.8% vs. 12.2 +/- 2.4%) in the control group. The trained group showed higher NE values before (0.40 +/- 0.04 vs. 0.36 +/- 0.05) and after atropine (0.37 +/- 0.04 vs. 0.34 +/- 0.06; p = 0.08). Training decreased the CV of NE both before (23.3 +/- 2% vs. 25.2 +/- 4%; p = 0.08) and after parasympathetic blockade (22.6 +/- 1% vs. 26.1 +/- 5%). Cholinergic blockade did not modify these parameters within the control and trained groups. Activation complexity was lower in the trained than in the control animals before atropine (34 +/- 8 vs. 41 +/- 5), and increased after atropine in the control group (41 +/- 5 vs. 48 +/- 9, respectively). Thus, training decreases the intrinsic heterogeneity of the myocardium, increases electrophysiological stability, and prevents some modifications due to muscarinic block.This research was supported by the Spanish Ministry of Education and Science, (DEP2007-73234-C03-01 to AMA), http://www.mecd.gob.es/portada-mecd/; and the Generalitat Valenciana (PROMETEO 2010/093 to FJC, and FPI/2008/003 to MZ), http://www.gva.es/va/inicio/presentacion; jsessionid=ydprbDQZTsCTz85W1Such-Miquel, L.; Brines-Ferrando, L.; Alberola, A.; Zarzoso Muñoz, M.; Chorro Gasco, FJ.; Guerrero-Martínez, JF.; Parra-Giraldo, G.... (2018). Effect of chronic exercise on myocardial electrophysiological heterogeneity and stability. Role of intrinsic cholinergic neurons: A study in the isolated rabbit heart. 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N., & Quindry, J. C. (2014). Mechanisms of Exercise-Induced Cardioprotection. Physiology, 29(1), 27-38. doi:10.1152/physiol.00030.2013Hull, S. S., Vanoli, E., Adamson, P. B., Verrier, R. L., Foreman, R. D., & Schwartz, P. J. (1994). Exercise training confers anticipatory protection from sudden death during acute myocardial ischemia. Circulation, 89(2), 548-552. doi:10.1161/01.cir.89.2.548Hajnal, Á., Nagy, O., Litvai, Á., Papp, J., Parratt, J. R., & Végh, Á. (2005). Nitric oxide involvement in the delayed antiarrhythmic effect of treadmill exercise in dogs. Life Sciences, 77(16), 1960-1971. doi:10.1016/j.lfs.2005.02.015Such, L., Alberola, A. M., Such-Miquel, L., López, L., Trapero, I., Pelechano, F., … Chorro, F. J. (2008). Effects of chronic exercise on myocardial refractoriness: a study on isolated rabbit heart. Acta Physiologica, 193(4), 331-339. doi:10.1111/j.1748-1716.2008.01851.xZarzoso, M., Such-Miquel, L., Parra, G., Brines-Ferrando, L., Such, L., Chorro, F. J., … Alberola, A. (2011). The training-induced changes on automatism, conduction and myocardial refractoriness are not mediated by parasympathetic postganglionic neurons activity. European Journal of Applied Physiology, 112(6), 2185-2193. doi:10.1007/s00421-011-2189-4Billman, G. E. (2009). Cardiac autonomic neural remodeling and susceptibility to sudden cardiac death: effect of endurance exercise training. American Journal of Physiology-Heart and Circulatory Physiology, 297(4), H1171-H1193. doi:10.1152/ajpheart.00534.2009HAN, J., & MOE, G. K. (1964). Nonuniform Recovery of Excitability in Ventricular Muscle. Circulation Research, 14(1), 44-60. doi:10.1161/01.res.14.1.44Beaumont, E., Salavatian, S., Southerland, E. M., Vinet, A., Jacquemet, V., Armour, J. A., & Ardell, J. L. (2013). Network interactions within the canine intrinsic cardiac nervous system: implications for reflex control of regional cardiac function. The Journal of Physiology, 591(18), 4515-4533. doi:10.1113/jphysiol.2013.259382Armour, J. A. (2008). Potential clinical relevance of the ‘little brain’ on the mammalian heart. Experimental Physiology, 93(2), 165-176. doi:10.1113/expphysiol.2007.041178Abramochkin, D. V., Nurullin, L. F., Borodinova, A. A., Tarasova, N. V., Sukhova, G. S., Nikolsky, E. E., & Rosenshtraukh, L. V. (2009). Non-quantal release of acetylcholine from parasympathetic nerve terminals in the right atrium of rats. Experimental Physiology, 95(2), 265-273. doi:10.1113/expphysiol.2009.050302CHORRO, F. J., CANOVES, J., GUERRERO, J., MAINAR, L., SANCHIS, J., SORIA, E., … LOPEZ-MERINO, V. (2000). Opposite Effects of Myocardial Stretch and Verapamil on the Complexity of the Ventricular Fibrillatory Pattern: An Experimental Study. Pacing and Clinical Electrophysiology, 23(11), 1594-1603. doi:10.1046/j.1460-9592.2000.01594.xSuch, L., Rodriguez, A., Alberola, A., Lopez, L., Ruiz, R., Artal, L., … Chorro, F. J. (2002). 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    Bronchoscopist's perception of the quality of the single-use bronchoscope (Ambu aScope4™) in selected bronchoscopies: a multicenter study in 21 Spanish pulmonology services

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    Background: The disposable bronchoscope is an excellent alternative to face the problem of SARS-CoV-2 and other cross infections, but the bronchoscopist's perception of its quality has not been evaluated. Methods: To evaluate the quality of the Ambu-aScope4 disposable bronchoscope, we carried out a cross-sectional study in 21 Spanish pulmonology services. We use a standardized questionnaire completed by the bronchoscopists at the end of each bronchoscopy. The variables were described with absolute and relative frequencies, measures of central tendency and dispersion depending on their nature. The existence of learning curves was evaluated by CUSUM analysis. Results: The most frequent indications in 300 included bronchoscopies was bronchial aspiration in 69.3% and the median duration of these was 9.1 min. The route of entry was nasal in 47.2% and oral in 34.1%. The average score for ease of use, image, and aspiration quality was 80/100. All the planned techniques were performed in 94.9% and the bronchoscopist was satisfied in 96.6% of the bronchoscopies. They highlighted the portability and immediacy of the aScope4TM to start the procedure in 99.3%, the possibility of taking and storing images in 99.3%. The CUSUM analysis showed average scores > 70/100 from the first procedure and from the 9th procedure more than 80% of the scores exceeded the 80/100 score. Conclusions: The aScope4™ scored well for ease of use, imaging, and aspiration. We found a learning curve with excellent scores from the 9th procedure. Bronchoscopists highlighted its portability, immediacy of use and the possibility of taking and storing images

    Bronchoscopist's perception of the quality of the single-use bronchoscope (Ambu aScope4™) in selected bronchoscopies: a multicenter study in 21 Spanish pulmonology services

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    Background: The disposable bronchoscope is an excellent alternative to face the problem of SARS-CoV-2 and other cross infections, but the bronchoscopist’s perception of its quality has not been evaluated. Methods: To evaluate the quality of the Ambu-aScope4 disposable bronchoscope, we carried out a cross-sectional study in 21 Spanish pulmonology services. We use a standardized questionnaire completed by the bronchoscopists at the end of each bronchoscopy. The variables were described with absolute and relative frequencies, measures of cen‑ tral tendency and dispersion depending on their nature. The existence of learning curves was evaluated by CUSUM analysis. Results: The most frequent indications in 300 included bronchoscopies was bronchial aspiration in 69.3% and the median duration of these was 9.1 min. The route of entry was nasal in 47.2% and oral in 34.1%. The average score for ease of use, image, and aspiration quality was 80/100. All the planned techniques were performed in 94.9% and the bronchoscopist was satisfed in 96.6% of the bronchoscopies. They highlighted the portability and immediacy of the aScope4TM to start the procedure in 99.3%, the possibility of taking and storing images in 99.3%. The CUSUM analysis showed average scores>70/100 from the frst procedure and from the 9th procedure more than 80% of the scores exceeded the 80/100 score

    Bronchoscopist's perception of the quality of the single-use bronchoscope (Ambu aScope4™) in selected bronchoscopies : a multicenter study in 21 Spanish pulmonology services

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    Background: The disposable bronchoscope is an excellent alternative to face the problem of SARS-CoV-2 and other cross infections, but the bronchoscopist's perception of its quality has not been evaluated. Methods: To evaluate the quality of the Ambu-aScope4 disposable bronchoscope, we carried out a cross-sectional study in 21 Spanish pulmonology services. We use a standardized questionnaire completed by the bronchoscopists at the end of each bronchoscopy. The variables were described with absolute and relative frequencies, measures of central tendency and dispersion depending on their nature. The existence of learning curves was evaluated by CUSUM analysis. Results: The most frequent indications in 300 included bronchoscopies was bronchial aspiration in 69.3% and the median duration of these was 9.1 min. The route of entry was nasal in 47.2% and oral in 34.1%. The average score for ease of use, image, and aspiration quality was 80/100. All the planned techniques were performed in 94.9% and the bronchoscopist was satisfied in 96.6% of the bronchoscopies. They highlighted the portability and immediacy of the aScope4TM to start the procedure in 99.3%, the possibility of taking and storing images in 99.3%. The CUSUM analysis showed average scores > 70/100 from the first procedure and from the 9th procedure more than 80% of the scores exceeded the 80/100 score. Conclusions: The aScope4™ scored well for ease of use, imaging, and aspiration. We found a learning curve with excellent scores from the 9th procedure. Bronchoscopists highlighted its portability, immediacy of use and the possibility of taking and storing images
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