1,964 research outputs found

    Tree-structure Expectation Propagation for Decoding LDPC codes over Binary Erasure Channels

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    Expectation Propagation is a generalization to Belief Propagation (BP) in two ways. First, it can be used with any exponential family distribution over the cliques in the graph. Second, it can impose additional constraints on the marginal distributions. We use this second property to impose pair-wise marginal distribution constraints in some check nodes of the LDPC Tanner graph. These additional constraints allow decoding the received codeword when the BP decoder gets stuck. In this paper, we first present the new decoding algorithm, whose complexity is identical to the BP decoder, and we then prove that it is able to decode codewords with a larger fraction of erasures, as the block size tends to infinity. The proposed algorithm can be also understood as a simplification of the Maxwell decoder, but without its computational complexity. We also illustrate that the new algorithm outperforms the BP decoder for finite block-siz

    Signaling Proteins and Transcription Factors in Normal and Malignant Early B Cell Development

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    B cell development starts in bone marrow with the commitment of hematopoietic progenitors to the B cell lineage. In murine models, the IL-7 and preBCR receptors, and the signaling pathways and transcription factors that they regulate, control commitment and maintenance along the B cell pathway. E2A, EBF1, PAX5, and Ikaros are among the most important transcription factors controlling early development and thereby conditioning mice homeostatic B cell lymphopoiesis. Importantly, their gain or loss of function often results in malignant development in humans, supporting conserved roles for these transcription factors. B cell acute lymphoblastic leukemia is the most common cause of pediatric cancer, and it is characterized by unpaired early B cell development resulting from genetic lesions in these critical signaling pathways and transcription factors. Fine mapping of these genetic abnormalities is allowing more specific treatments, more accurately predicting risk profiles for this disease, and improving survival rates

    Tree-Structure Expectation Propagation for LDPC Decoding over the BEC

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    We present the tree-structure expectation propagation (Tree-EP) algorithm to decode low-density parity-check (LDPC) codes over discrete memoryless channels (DMCs). EP generalizes belief propagation (BP) in two ways. First, it can be used with any exponential family distribution over the cliques in the graph. Second, it can impose additional constraints on the marginal distributions. We use this second property to impose pair-wise marginal constraints over pairs of variables connected to a check node of the LDPC code's Tanner graph. Thanks to these additional constraints, the Tree-EP marginal estimates for each variable in the graph are more accurate than those provided by BP. We also reformulate the Tree-EP algorithm for the binary erasure channel (BEC) as a peeling-type algorithm (TEP) and we show that the algorithm has the same computational complexity as BP and it decodes a higher fraction of errors. We describe the TEP decoding process by a set of differential equations that represents the expected residual graph evolution as a function of the code parameters. The solution of these equations is used to predict the TEP decoder performance in both the asymptotic regime and the finite-length regime over the BEC. While the asymptotic threshold of the TEP decoder is the same as the BP decoder for regular and optimized codes, we propose a scaling law (SL) for finite-length LDPC codes, which accurately approximates the TEP improved performance and facilitates its optimization

    Estudio descriptivo de los hábitos alimenticios y del consumo de alcohol en una muestra de estudiantes de la Universidad de Alicante

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    Objetivo. Describir la frecuencia de consumo de determinados alimentos y bebidas alcohólicas en una muestra de estudiantes de la Universidad de Alicante. Material y métodos. El instrumento utilizado para la recogida de datos fue un cuestionario de frecuencias de consumo, aplicado mediante entrevista personal a una muestra accidental de 1250 personas, (692 mujeres y 488 hombres), con un rango de edad de 17-40 años. Constaba de cuatro secciones: 1ª) número de comidas y lugar donde se realizan; 2ª) patrones de consumo de los distintos grupos de alimentos; 3ª) patrones de consumo de bebidas alcohólicas, diferenciando lo bebido de lunes a jueves y de viernes a domingo; y 4ª) datos de identificación y demográficos. Resultados. Los datos obtenidos coinciden con los expuestos por otros autores, y muestran que nuestro modelo alimentario se caracteriza por un alto consumo de carnes (=4 veces/semana), adecuada ingesta de huevos (=2,5 v/sem.) e hidratos de carbono complejos (arroz y pastas =4,2 v/sem.), consumo ligeramente inferior al recomendado de frutas (=5,3 v/sem.) e insuficiente de legumbres (=2,2 v:/sem.), verduras y hortalizas frescas (=3,9 v/sem.), y pescados (=2 v/sem.). El consumo de bebidas alcohólicas fue: 2,6 vasos/semana de cerveza, 2,1 v/sem. de combinados, 1,2 v/sem. de licores y 0,8 v/sem. de vino. Los porcentajes de consumidores fueron para la cerveza del 51,1 %, para los combinados del 61,4%, para los licores del 40,9%, y para el vino 18,7%. Los datos señalan que los hombres consumen más bebidas alcohólicas que las mujeres (t=7,79 p<0,001) y que quienes empiezan antes a consumirlas son quienes en mayor cantidad lo hacen (t=-3,17 p<0,001). Conclusiones. Pese a la diferencia existente entre medias de edad y nivel cultural, existe una similitud entre los datos obtenidos en este estudio y el realizado sobre la población de la ciudad de Alicante. Las encuestas alimentarias y de consumo de alcohol realizadas en España son escasas y con diversa metodología, lo que dificulta la comparación de los resultados obtenidos con otros estudios previos

    Strength tests on asphalt mixes attacked by motor fuels. Recommendations on bath immersion times

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    [Abstract:] One of the limitations of asphalt mixes as pavement materials is their poor resistance to attack from crude oil-based motor fuels. Several procedures exist for determining the resistance of asphalt materials to motor fuel action. Different test standards can be found for fillers and surface dressings in both the US and European series. However, where the assessment of asphalt mixes themselves are concerned, there is a considerable lack of standardisation. This paper reports on laboratory studies on certain essential aspects of the procedures for assessing the strength of asphalt mixes in respect of motor fuel attack, chiefly the time the mix is exposed to the fuel. Based on the research results, the paper makes some good-practice recommendations for weight-loss procedures after immersion in motor fuel, with or without subsequent brushing, and in respect of the Marshall stability preserved after immersion. In relation to the immersion period and in view of the laboratory findings and their subsequent statistical processing, one of the factors with the greatest influence is the recommendation that the immersion period should be 24 hours, except in the weight-loss test subseuent to immersion without any brushing where the results obtained prove to be more significant if the immersion period is seven days

    New properties of a bioinspired pyridine benzimidazole compound as a novel differential staining agent for endoplasmic reticulum and Golgi apparatus in fluorescence live cell imaging

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    Indexación: Scopus.In this study, we explored new properties of the bioinspired pyridine benzimidazole compound B2 (2,4-di-tert-butyl-6-(3H-imidazo[4,5-c]pyridine-2-yl)phenol) regarding its potential use as a differential biomarker. For that, we performed 1D 1HNMR (TOCSY), UV-Vis absorption spectra in different organic solvents, voltammetry profile (including a scan-rate study), and TD-DFT calculations that including NBO analyses, to provide valuable information about B2 structure and luminescence. In our study, we found that the B2 structure is highly stable, where the presence of an intramolecular hydrogen bond (IHB) seems to have a crucial role in the stability of luminescence, and its emission can be assigned as fluorescence. In fact, we found that the relatively large Stokes Shift observed for B2 (around 175 nm) may be attributed to the stability of the B2 geometry and the strength of its IHB. On the other hand, we determined that B2 is biocompatible by cytotoxicity experiments in HeLa cells, an epithelial cell line. Furthermore, in cellular assays we found that B2 could be internalized by passive diffusion in absence of artificial permeabilization at short incubation times (15 min to 30 min). Fluorescence microscopy studies confirmed that B2 accumulates in the endoplasmic reticulum (ER) and Golgi apparatus, two organelles involved in the secretory pathway. Finally, we determined that B2 exhibited no noticeable blinking or bleaching after 1 h of continuous exposure. Thus, B2 provides a biocompatible, rapid, simple, and efficient way to fluorescently label particular organelles, producing similar results to that obtained with other well-established but more complex methods. © 2018 Llancalahuen, Fuentes, Carreño, Zúñiga, Páez-Hernández, Gacitúa, Polanco, Preite, Arratia-Pérez and Otero.https://www.frontiersin.org/articles/10.3389/fchem.2018.00345/ful

    Effect of small-sided games on football players

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    El objetivo ha sido analizar cómo influyen los juegos reducidos o SSGs sobre la condición física, técnica y los cambios de dirección (CODA) en jugadoras alevines de fútbol femenino. Participan 12 jugadoras de fútbol femenino. Realizaron 14 sesiones de entrenamiento basado en juegos reducidos de fútbol. La muestra presenta valores normales en la prueba de Saphiro-Wilk, además, en la prueba de t de Student muestra que existen diferencias estadísticamente muy significativas (p ≤0,00) en todas las variables físicas analizadas, menos en el caso de la fuerza explosiva. En las variables de técnica nos muestra que existen diferencias significativas en todas las variables analizadas (p ≤0,00). Por último existen correlaciones positivas y estadísticamente significativas entre las distintas variables analizadas. De esta forma podemos considerar los juegos reducidos son un método adecuado y muy ventajoso para el entrenamiento en las etapas iniciales o de formación en jugadoras de fútbolThe objective has been to analyze how small-sided games or SSGs affect physical, technical and changes of direction (CODA) in U12 female soccer players. 12 female soccer players participate. They conducted 14 training sessions based on reduced soccer games. The sample has normal values in the Saphiro-Wilk test, and in the Student's t test it shows that there are statistically very significant differences (p ≤0,00) in all the analyzed physical variables, less in the case of the explosive force. In the technique variables we show that there are significant differences in all variables analyzed (p ≤0,00). Finally, there are positive and statistically significant correlations between the different variables analyzed. In this way we can consider reduced games are a suitable and very advantageous method for training in the initial stages or training in soccer player

    Diseño de modelo de negocio: reparación por sí mismo de desperfectos en casa

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    El enfoque de este proyecto, son aquellas mujeres que buscan ser independientes en prácticas cotidianas que hacen referencia a reparaciones domésticas, mantenimiento y proyectos de reformas en el hogar o negocio. Se identificó que existen productos en el mercado que ofrecen la información y las herramientas en sus manuales de uso, pero que en la práctica se vuelven complicados de seguir, para que dichas mujeres sean capaces de arreglar los desperfectos por si solas. Por consecuencia, no se atiende el problema detrás del problema, que es brindarles independencia. Para esta tesis, se consultaron distintas fuentes de información y metodologías para el planteamiento de soluciones, experimentaciones, propuesta y evolución de hipótesis, descubrimiento de hallazgos, y el planteamiento de una innovación. Las metodologías y herramientas utilizadas fueron: Design Thinking, Lean start-up, Customer Developement y Business Model Canvas. Para describir el mercado meta se hizo un análisis de la población en el que se consultaron distintas fuentes como CONAPO, INEGI, la Asociación Mexicana de Internet, entre otros. Mientras que, para el desarrollo del arquetipo, se llevaron a cabo más de 100 entrevistas y distintos experimentos; mismos que ayudaron a identificar información de valor como: sus pains, motivadores, estilo de vida, valores, punto de contacto, etc. Con el objetivo de hacer de esto un proyecto rentable se llevaron a cabo investigaciones como análisis del mercado, estrategia de precios, protocolos de seguimiento y atención postventa, entre otros. Después de 6 experimentos, algunos pivotes y ajustes acompañados de 3 evoluciones del PMV (Producto Mínimo Viable) se concluyó que el proyecto llamado Learn Lab es viable; además de identificar que existe probabilidad de crecimiento del proyecto ofreciendo un espacio de aprendizaje y convivencia para aquellos que atesoran la interacción, el aprendizaje y el conocimiento en distintos temas.ITESO, A.C
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