436 research outputs found

    Indexed left atrial size predicts all-cause and cardiovascular mortality in patients undergoing aortic valve surgery

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    [Abstract] OBJECTIVES: The enlargement of the left atrium has been identified as a marker of chronically increased left ventricular filling pressure and left ventricular diastolic dysfunction. This study aims to evaluate the association of indexed left atrial diameter with stroke, cardiovascular mortality, the combined event, and all-cause mortality in patients who underwent aortic valve surgery. METHODS: Indexed left atrial diameter was measured in 2011 adult patients (mean age, 70.9 ± 10.8 years; 58.7% were men) who underwent aortic valve surgery between January 2008 and March 2016. RESULTS: On the basis of the criteria of the American Society of Echocardiography, indexed left atrial diameter was normal in 64% of patients, mildly enlarged in 12.4% of patients, moderately enlarged in 9.2% of patients, and severely enlarged in 14.3% of patients. Over a mean follow-up period of 3.2 ± 2.1 years, there were 334 deaths and 97 strokes. Cardiovascular mortality survival at 5 years among patients with normal, mild, moderate, and severe left atrial enlargement was 91.6%, 86.8%, 77.9%, and 77.4%, respectively (P < .001). After covariable adjustment, Cox regression analysis showed indexed left atrial diameter as an independent predictor of all-cause mortality (hazard ratio per 1-cm/m2 increment, 1.545; 95% confidence interval, 1.252-1.906, P < .001), cardiovascular death (hazard ratio per 1-cm/m2 increment, 1.971; 95% confidence interval, 1.541-2.520; P < .001), and the combined event (hazard ratio per 1-cm/m2 increment, 1.673; 95% confidence interval, 1.321-2.119; P < .001). CONCLUSIONS: Indexed left atrial diameter is a strong predictor of long-term outcomes in patients with aortic valve diseases who undergo surgery

    Chemical composition and in situ ruminal disappearance of sorghum silages grown in the mexican humid tropic

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    The purpose was to evaluate the chemical composition and in situ ruminal dry matter disappearance of four types of grain sorghum silages, one brown midrib sorghum (bmr) and, a corn silage, grown under rainfed conditions in a humid tropical region of Mexico. The crops were established at three sites. At harvest, three minisilos per treatment were filled with forage previously chopped. Minisilos opened at 55 days and samples of silage taken to dry and ground to 1 mm to determine the chemical composition and in situ ruminal dry matter disappearance. The crude protein was higher (p&lt;0.05) in sorghum silages than corn silage. In sorghum silages, bmr sorghum had the lowest (p0.05) in ADF and ADL to corn silage. The degradation parameters (a, b, c ) was higher (p0.05) in bmr sorghum and corn silages. In the humid tropics, bmr sorghum silages are a good alternative to corn silage, especially in the dry season.The purpose was to evaluate the chemical composition and in situ ruminal dry matter disappearance of four types of grain sorghum silages, one brown midrib sorghum (bmr) and, a corn silage, grown under rainfed conditions in a humid tropical region of Mexico. The crops were established at three sites. At harvest, three minisilos per treatment were filled with forage previously chopped. Minisilos opened at 55 days and samples of silage taken to dry and ground to 1 mm to determine the chemical composition and in situ ruminal dry matter disappearance. The crude protein was higher (p&lt;0.05) in sorghum silages than corn silage. In sorghum silages, bmr sorghum had the lowest (p0.05) in ADF and ADL to corn silage. The degradation parameters (a, b, c ) was higher (p0.05) in bmr sorghum and corn silages. In the humid tropics, bmr sorghum silages are a good alternative to corn silage, especially in the dry season. &nbsp

    Polyphenolic Profile and Antioxidant Activity of Leaf Purified Hydroalcoholic Extracts from Seven Mexican Persea americana Cultivars

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    Persea americana (avocado) is a fruit consumed worldwide; however, since avocado leaves are apparently a natural ingredient that can be used as a traditional medicine, they can be a potential source of bioactive compounds. This study aimed to analyze the antioxidant activity of seven Mexican avocado leaf extracts by DPPH•, ABTS•+, and lipid peroxidation (LPO), and to identify the compoundprofilebyliquidchromatographycoupledtomassspectrometry/electronsprayionization. The highest free radical-scavenging activity was observed for Platano Delgado and Criollo 6 avocado cultivars havin IC50 values of 271.86 ± 13.69 and 269.56 ± 6.53 for DPPH• and ABTS•+ radicals, respectively, while the best result for lipid oxidation inhibition was registered in Criollo 6 cultivar extract. Inthisstudyfortyonecompoundsweredetectedinavocadoleavesofthethesevencultivars analyzed, and of these compounds, eighteen phenolics were identified for first time in such plant material. The present study demonstrated that Mexican cultivars of Persea americana possess diverse polyphenolic compounds with strong antioxidant activity, which might be useful in the food and pharmaceutical industries

    RESISTENCIA AL DESGASTE EN DEPÓSITOS DE SOLDADURA CON ALTO CONTENIDO DE Cr SOBRE UN ACERO ASTM A128

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    En la minería se utiliza el proceso de trituración de mineral, en este proceso algunos elementos de máquina sufren desgaste, estos componentes como martillos y conos trituradores son fabricados de acero Hadfield (ASTM A128) con el 12% al 14% de Mn. El desgaste ocurre cuando estos elementos de máquina tienen contacto directo con partículas abrasivas, debido a esto, y al costo elevado de compra, la recuperación de estas piezas es fundamental, para ello se utiliza el proceso de soldadura SMAW (Shield Metal Arc Welding) para la recuperación a través de depósitos de soldadura mediante electrodos con medio y alto contenido de Cr. En esta investigación se evalúa la microestructura, microdureza y el desgaste por abrasión bajo la norma ASTM G65 de cinco tipos de electrodos comerciales depositados en el acero ASTM A128. Se observó que la cantidad de Cr en el depósito tiene efecto en la cantidad de carburos, donde un aumento de carburos de Cr puede repercutir negativamente en el desgaste abrasivo. La microdureza tiene injerencia en la resistencia al desgaste abrasivo de manera opuesta a lo esperado, donde menor cantidad de carburos presentan una pérdida de masa mínima de material con respecto al acero ASTM A128

    Conflictos socioambientales y alternativas de la sociedad civil

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    Los conflictos socioambientales se multiplican en todo el mundo. Giran en torno a la contaminación industrial, las actividades mineras, el cambio de uso de suelo, la deforestación, la construcción de presas, la introducción de semillas genéticamente modificadas, el mal manejo de desechos sólidos y la privatización de tierra, agua y biodiversidad, entre otros. ¿Cuáles son las causas subyacentes a estos conflictos? ¿Quiénes son los protagonistas? ¿Cuáles son sus demandas, propuestas y estrategias? ¿En qué medida han contribuido a proteger o sanear el medio ambiente? ¿Hay conflictos locales que se convierten en glocales con la intervención de la sociedad civil? Estas interrogantes se abordan en este libro, que recoge inventarios de conflictos ambientales en México, en especial en Jalisco.ITESO, A.C

    Probability-based Dynamic Time Warping and Bag-of-Visual-and-Depth-Words for Human Gesture Recognition in RGB-D

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    We present a methodology to address the problem of human gesture segmentation and recognition in video and depth image sequences. A Bag-of-Visual-and-Depth-Words (BoVDW) model is introduced as an extension of the Bag-of-Visual-Words (BoVW) model. State-of-the-art RGB and depth features, including a newly proposed depth descriptor, are analysed and combined in a late fusion form. The method is integrated in a Human Gesture Recognition pipeline, together with a novel probability-based Dynamic Time Warping (PDTW) algorithm which is used to perform prior segmentation of idle gestures. The proposed DTW variant uses samples of the same gesture category to build a Gaussian Mixture Model driven probabilistic model of that gesture class. Results of the whole Human Gesture Recognition pipeline in a public data set show better performance in comparison to both standard BoVW model and DTW approach

    Caracterización edafológica con cultivo de agave azul (Agave tequilana Weber) en Tonaya y Tuxcacuesco, Jalisco, México

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    El cultivo del agave azul es de importancia económica en el estado de Jalisco, genera gran cantidad de empleos y es la principal fuente económica de varios municipios como es el caso de Tonaya y Tuxcacuesco. No obstante, en la actualidad se desconoce el estado edafológico de los suelos, se exhibe un limitado conocimiento de los factores que regulan el crecimiento del cultivo, lo que propicia que los rendimientos en el cultivo no se consideren óptimos. En este sentido, el objetivo de esta investigación fue evaluar el estado de la fertilidad de los suelos cultivados con agave azul en parcelas con distintas características (vírgenes y con varios ciclos de siembra) y diagnosticar su estado, en los municipios de Tonaya y Tuxcacuesco, con el fin de proponer prácticas de manejo y nutrición eficientes. Se analizaron los suelos en laboratorio, encontrándose las siguientes características; los resultados obtenidos evidencian que en promedio los suelos presentaron valores de pH de 7.7, la concentración de materia orgánica con promedio de 2.19%, en la mayoría de los sitios se encontraron deficiencias de nitrógeno, fósforo y potasio, clasificando a los suelos en la categoría de bajos a pobres en cuanto al contenido nutricional. Con base en los análisis estadísticos se demostró que no existen diferencias significativas entre los tipos de parcelas evaluadas, su contenido de materia orgánica y nutrientes. En cuanto a las prácticas de manejo se recomienda utilizar abonos orgánicos y el sistema de policultivo frijol, maíz y agave cuando el contexto agrícola y económico lo permitan

    Criterios de ordenación temporal de las intervenciones quirúrgicas en patología cardiovascular y endovascular adquirida. Versión 2022

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    Waiting list management of cardiac surgical procedures is a main concern for all the Spanish autonomic health systems and for our scientific Society. The first statement for optimal timing of patients waiting for cardiac surgery was published in 2000. Since then, after significant changes in the management of some pathologies, new normative frameworks and the current healthcare situation, a review of the timing criteria to offer an adequate and updated standard of care is needed. In this document we aim to review the available literature in the field and stablish a consensus within a working group of the Spanish Society of Cardiovascular and Endovascular Surgery to optimize the priority recommendations in cardiac surgical waiting lists in our country. (c) 2022 Sociedad Espanola de Cirugia Cardiovascular y Endovascular. Published by Elsevier Espana, S.L.U. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/ riccuses/by-nc-nri/4.0/)

    Vocabulario de la sociedad civil, la ruralidad y los movimientos sociales en América Latina

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    El Vocabulario de la Sociedad Civil, la Ruralidad y los Movimientos Sociales en América Latina tiene como objetivo desarrollar vocablos relacionados con temas de gran trascendencia para la vida colectiva de la población Latinoamericana; pretende introducir a estudiantes, personas del ámbito académico y activistas en la comprensión de estas categorías de análisis. A través de la mirada de 70 especialistas que participaron en este vocabulario, es posible comprender muchos de los términos que se utilizan dentro de la investigación social y áreas relacionadas con las ciencias políticas, ambientales y rurales, a partir de una mayor explicación y detalle. Es por ello que se inserta este trabajo desde una mirada colectiva y amplia de los conceptos que se exponen. En este libro podrá encontrar las ideas de varios autores y autoras de distintas universidades, con una visión multi, inter y transdisciplinaria. El esfuerzo que se realizó para conjuntar varios términos y analizar su compleja red de interpretaciones, permitirá que este manuscrito pueda ser consultado por estudiantes, personas del ámbito científico-académico, y ciudadanía; porque contiene el estado del arte, la historia del paulatino avance de múltiples conceptos y su vigencia en el contexto actual

    Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

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    The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality
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