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Sample records for al ajoene usando

  1. Antifungal activity of ajoene derived from garlic.

    OpenAIRE

    Yoshida, S.(Department of Physics, Chiba University, 263-8522, Chiba, Japan); Kasuga, S; Hayashi, N; Ushiroguchi, T; Matsuura, H.; Nakagawa, S

    1987-01-01

    The antifungal activity of six fractions derived from garlic was investigated in an in vitro system. Ajoene had the strongest activity in these fractions. The growth of both Aspergillus niger and Candida albicans was inhibited by ajoene at less than 20 micrograms/ml.

  2. The garlic compound ajoene targets protein folding in the endoplasmic reticulum of cancer cells.

    Science.gov (United States)

    Kaschula, Catherine H; Hunter, Roger; Cotton, Jonathan; Tuveri, Rossana; Ngarande, Ellen; Dzobo, Kevin; Schäfer, Georgia; Siyo, Vuyolwethu; Lang, Dirk; Kusza, Daniel A; Davies, Bronwen; Katz, Arieh A; Parker, M Iqbal

    2016-08-01

    Ajoene is a natural allylsulfur compound found in crushed garlic that arrests growth and induces apoptosis in cancer cells. To gain mechanistic insights into the cytotoxicity of ajoene in cancer cells, two fluorescently labelled ajoene analogs with dansyl- (DP) and fluorescein- (FOX) tags were synthesized. The tagged ajoenes were found to retain their activity at inhibiting proliferation and inducing apoptosis in MDA-MB-231 human breast-cancer and WHCO1 human esophageal-cancer cells. Both tagged ajoenes localized to the endoplasmic reticulum (ER) in MDA-MB-231 cells as observed by live cell confocal laser scanning microscopy (CLSM) and confirmed by generating an MDA-MB-231 cell line expressing yellow fluorescent protein (YFP) in the ER. DP appears to S-thiolate multiple protein targets in MDA-MB-231 cells as observed by immunoblotting under non-reducing conditions only; and a competition assay demonstrated that DP and Z-ajoene in fact share the same target. Ajoene S-thiolation interfered with protein folding and led to an accumulation of misfolded protein aggregates and activated the unfolded protein response (UPR). Consistent with this mechanism, increased levels of GRP78 and total ubiquitinated proteins were observed; and an ER-folded protein, type-1 collagen, was tracked to the proteasome following ajoene treatment. The intracellular protein aggregates were observed by CLSM and transmission electron microscopy (TEM). This is the first time that ajoene has been shown to target protein folding in the ER of cancer cells. © 2015 Wiley Periodicals, Inc. PMID:26207910

  3. Ajoene, a Sulfur-Rich Molecule from Garlic, Inhibits Genes Controlled by Quorum Sensing

    DEFF Research Database (Denmark)

    Jakobsen, Tim Holm; van Gennip, Maria; Phipps, Richard Kerry;

    2012-01-01

    the expression of specific genes involved in pathogenicity, is a possible drug target. Previous in vitro and in vivo studies revealed a significant inhibition of P. aeruginosa QS by crude garlic extract. By bioassay-guided fractionation of garlic extracts, we determined the primary QS inhibitor...... present in garlic to be ajoene, a sulfur-containing compound with potential as an antipathogenic drug. By comprehensive in vitro and in vivo studies, the effect of synthetic ajoene toward P. aeruginosa was elucidated. DNA microarray studies of ajoene-treated P. aeruginosa cultures revealed a concentration...

  4. APROXIMACIÓN AL ANÁLISIS DE LA VALORACIÓN DE LA PRUEBA USANDO MODIFIED WIGMOREAN ANALYSIS (MWA

    Directory of Open Access Journals (Sweden)

    Carlos del Valle Rojas

    2009-01-01

    Full Text Available El presente trabajo muestra cómo el análisis de la valoración de la prueba, usando herramientas de diagramación argumental, puede ayudar a los operadores jurídicos a evaluar la calidad de la argumentación del razonamiento jurídico. Se aplica el Modified Wigmorean Analysis (MWA a un caso penal hipotético y a un caso real, ensayando el proceso de análisis y diagramación y probando su utilidad. La conclusión reseña las ventajas y debilidades del análisis y sugiere ajustes al proceso de diagramación.The present work shows how the analysis of the valuation of the proof, using tools of plot diagramming, can help the juridical operators to evaluate the quality of the argumentation of the juridical reasoning. There is applied the Modified Wigmorean Analysis (MWA to a penal hypothetical case and to a real case, testing the process of analysis and diagramming and proving his utility. The conclusion outlines the advantages and weaknesses of the analysis and suggests adjustments to the process of diagramming.

  5. Caracterización de la diversidad genética en naranja y comparación del polimorfismo de microsatélites amplificados al azar (RAMs usando electroforesis de poliacrilamida y agarosa

    Directory of Open Access Journals (Sweden)

    Muñoz Flores Jaime Eduardo

    2009-12-01

    Full Text Available Se compararon las eficiencias de tres métodos de electroforesis en agarosa y poliacrilamida, usando la cámara pequeña de DNA Sequencing System y cámara grande OWL Sequi-Gen Sequencing Cell, en la detección del polimorfismo en 21 accesiones de naranja (Citrus sinensis con empleo del cebador CGA. El gel de poliacrilamida dio mejor resolución de los productos amplificados vía PCR producidos por RAMs. Este permitió una mejor detección de bandas de ADN polimórficas, lo que facilitó la identificación de la variabilidad genética. La electroforesis en agarosa puede ser más conveniente en otras aplicaciones, debido al bajo costo y fácil aplicación. El estudio de diversidad genética en naranja usando microsatélites RAMs diferenció 51 accesiones en siete grupos con 0.75 de similaridad y 0.25 de heterocigosidad, lo que revela bajo polimorfismo genético. La técnica RAMs permitió agrupar las accesiones en Comunes o Blancas, Navel y Pigmentadas o Sanguinas.

  6. Study of the mechanism of andalusite-Al°-N2 reaction using the combination of DTA-TG-DTG techniques Estudo do mecanismo da reação andalusita-Al°-N2 usando a combinação das técnicas ATD-ATG-TGD

    Directory of Open Access Journals (Sweden)

    A. D. Mazzoni

    1999-06-01

    Full Text Available Alumina based ceramics have important engineering applications due to their good physicochemical properties but their performance may be enhanced by addition of a second phase. Aluminosilicates as andalusite submitted to aluminium reduction and the simultaneous nitriding (N2 atmosphere leads to the obtention of alumina and phases of the Si-Al-O-N system. These phases are of great interest for structural ceramics. Mixes prepared with andalusite and Al° (different content were treated with N2 up to 1550 °C., using a heating rate of 5 °/min. Thermal effects (DTA and weight changes (TG, DTG of nitriding reactions during heating were evaluated. The reaction mechanism was determined using DTA-TG-DTG techniques. Results indicate that Si° and AlN are important intermediate phases during reactions. The final products were a-Al2O3 with sialons, mainly b’ phase and polytype sialons. The final formed phases depend on the Al° content and can be predicted using the Si-Al-O-N phase diagram.Cerâmicas à base de alumina apresentam importantes aplicações em engenharia por causa de suas boas propriedades físico-químicas; entretanto, seu desempenho pode ser melhorado pela adição de uma segunda fase. Aluminosilicatos tais como andalusita submetida a redução do alumínio e simultânea nitretação ( atmosfera de N2 leva a obtenção de alumina e fases do sistema Si-Al-O-N. Essas fases são de graande interesse em cerâmica estrutural. Misturas preparadas com andalusita e Al° (teor diferente foram tratadas com N2 até 1550° C, com taxa de aquecimento de 5° /min. Os efeitos térmicos (ATD e variações de massa (TG, DTG das reações de nitretação durante aquecimento foram determinados. O mecanismo da reação foi determinado usando as técnicas ATD-ATG-DTG. Os resultados mostram que Si° e AlN são fases intermediárias importantes durante as reações. Os produtos finais foram a-Al2O3 com sialons, principalmente a faseb’ e sialons politipos. As

  7. Modelo predictivo del espesor de la capa de óxido y microdureza en aluminio Al3003-B14 y Al6063-T6 anodizado usando análisis multifactorial Oxide film thickness and microhardness prediction model of Al3003-B14 and Al6063-T6 anodized aluminum using multifactorial analysis

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    Leonardo Eladio Vergara Guillén

    2011-08-01

    Full Text Available En esta investigación se modela a partir de los parámetros del proceso el espesor de la capa de óxido y la microdureza de los aluminios Al3003 y Al6063 anodizados. Para ello se realizaron estudios de la microdureza y espesor de capa de la superficie anodizada, utilizando técnicas de análisis multifactorial y diseño robusto. Se establecieron los siguientes niveles de los parámetros del proceso: temperatura [15 °C, 25 °C], tiempo [30 min; 60 min], concentración de electrolito [1,2 M; 2 M], densidad de corriente [1 Amp/dm²; 3 Amp/dm²], aluminio [Al3003,Al6063] y como variable de ruido, la deformación plástica [0%, 10%, 20%, 30%]. Se propuso un diseño fraccionado 2(7-2 mixto, con el cual se efectuó un total de 48 pruebas usando soluciones electrolíticas de ácido sulfúrico. La medición de microdureza se realizó con un indentador Vickers con carga de 400 g; el espesor de la capa de óxido se captó mediante microscopia electrónica. A los resultados se les realizó un análisis de varianza (ANOVA, para determinar los factores significativos y la robustez de los efectos. Se encontraron resultados de microdureza [HV] [85,74-308,87]; y espesor de óxido [µm] [12,82- 94,69]. Finalmente, se muestran los modelos de predicción de cada una de las respuestas en función de los factores significativos estas ecuaciones permitirán seleccionar la microdureza y espesor de la capa de óxido para cumplir los requerimientos de un producto particular mediante una selección apropiada de los parámetros del proceso.In this research, the thickness of the oxide layer and the microhardness of anodized aluminum Al3003 and Al6063 are modeled based on process parameters. To this end, studies of the microhardness and the thickness layer of the anodized surface were made, via techniques of multifactorial analysis and robust design. The following levels of the process parameters were established: temperature [15°C, 25°C], time [30min; 60min

  8. Aproximación no lineal al modelo de overshooting usando redes neuronales multicapa para el tipo de cambio dólar - peso

    OpenAIRE

    Jaime Villamil

    2009-01-01

    Desde los años setenta muchos trabajos han intentado elaborar una sustentación empírica de algunos modelos
    que ofrecieron una explicación lineal de la dinámica de la tasa de cambio de un país, entre ellos el de Dornbusch. Hasta el momento ninguno ha sido concluyente y la caminata aleatoria es considerada como el mejor modelo al que puede ajustarse. De Grauwe ha mostrado que, con la presencia de relaciones no-lineales y heterogeneidad de expectativas de los especuladores, el tipo de...

  9. Aproximación preliminar al estudio de la eficiencia de 5 subsectores de la economía colombiana usando DEA

    Directory of Open Access Journals (Sweden)

    Gloria Isabel Rodríguez Lozano

    1998-06-01

    Full Text Available En este articulo se analizan cinco subsectores de la economía colombiana aplicando una novedosa técnica que mide el desempeño relativo de unidades organizacionales ante la presencia de múltiples entradas y salidas, esta técnica se denomina DATA ENVELOPMENT ANALYSIS (DEA y ha sido desarrollada prioritariamente por académicos en Estados Unidos. Se han hecho aplicaciones en algunos subsectores y sectores de la economía estadounidense y de países europeos, demostrando ventajas sobre otro tipo de estudios y análisis aportados por el hecho de trabajar simultáneamente con diferentes recursos y diversos outputs; adicionalmente porque optimiza el comportamiento de cada una de las unidades organizacionales comparándolas entre ellas y sacando como fruto un grupo que compone la frontera de aquellas que son eficientes y arrojando datos que analizados reportan para cada una de las no eficientes el comportamiento que debería tener para mejorar su desempeño y lograr estar en este selecto grupo. Es necesario aclarar que las aplicaciones también se pueden adelantar al interior de una sola organización buscando medir el desempeño de los diferentes departamentos, sucursales, etc. con el objetivo de mejorar el desempeño de cada una de estas unidades para que finalmente se refleje en un mejoramiento global de la organización o empresa. En Colombia se está empezando a estudiar este novedoso tema y el trabajo de investigación llevado a cabo para la elaboración de la citada Tesis es hasta el momento uno de los primeros intentos de aplicación es necesario aclarar que no se encontraron investigaciones sobre este tema que hayan sido publicadas.

  10. Nueva Metodología Para Clasificar Datos de Series Temporales usando el Algoritmo Biclustering

    OpenAIRE

    Cogollo F. M.; Palacios, Alejandro

    2013-01-01

    En este trabajo se propone una metodología de clasificación de series temporales usando la técnica de extracción de características y el algoritmo de clasificación Biclustering, la cual permite trabajar con series temporales de distintas longitudes y con datos faltantes. Los resultados obtenidos con esta metodología son mejores al ser comparados con los obtenidos por medio del método tradicional K-medias usando datos experimentales.

  11. Caracterización de la diversidad genética en naranja y comparación del polimorfismo de microsatélites amplificados al azar (RAMs usando electroforesis de poliacrilamida y azarosa Characterization of the genetic diversity in orange, and comparison of polymorphism in randomly-amplifed microsatellites (RAMs, using polyacrylamide and agarose electrophoresis

    Directory of Open Access Journals (Sweden)

    Ana Cruz Morillo Coronado

    2009-10-01

    Full Text Available Se compararon las eficiencias de tres métodos de electroforesis en agarosa y poliacrilamida, usando la cámara pequeña de DNA Sequencing System y cámara grande OWL Sequi-Gen Sequencing Cell, en la detección del polimorfismo en 21 accesiones de naranja (Citrus sinensis con empleo del cebador CGA. El gel de poliacrilamida dio mejor resolución de los productos amplificados vía PCR producidos por RAMs. Este permitió una mejor detección de bandas de ADN polimórficas, lo que facilitó la identificación de la variabilidad genética. La electroforesis en agarosa puede ser más conveniente en otras aplicaciones, debido al bajo costo y fácil aplicación. El estudio de diversidad genética en naranja usando microsatélites RAMs diferenció 51 accesiones en siete grupos con 0.75 de similaridad y 0.25 de heterocigosidad, lo que revela bajo polimorfismo genético. La técnica RAMs permitió agrupar las accesiones en Comunes o Blancas, Navel y Pigmentadas o Sanguinas.We compared the efficiency of three methods of agarose and polyacrylamide electrophoresis (using the small tank of the DNA Sequencing System and the large OWL Sequi-Gen Sequencing Cell, for the detection of polymorphism in 21 accessions of orange (Citrus sinensis, using the primer CGA. The polyacrylamide gel gave better resolution of the PCR-amplified RAM products. This method allowed better detection of polymorphic DNA bands, facilitating the identification of genetic variability. The agarose electrophoresis may be more convenient in other applications, due to its low cost and easy implementation. The study of genetic diversity in orange using RAMs separated 51 accessions into seven groups with 0.75 similarity, and 0.25 heterozygosity, revealing low genetic polymorphism. The RAMs technique grouped the accessions into “Common or White”, “Navel” and “Pigmented or “Sanguine”.

  12. Control adaptable indirecto usando Redes Neuronales Dinámicas

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    M. A. Moreno Armendariz

    2001-01-01

    Full Text Available En este trabajo se propone un nuevo tipo de control no-lineal por retroalimentación para una clase de sistemas continuos no-lineales de una entrada y una salida de la siguiente forma: Se supone que el sistema no-lineal es desconocido, así una red neuronal dinámica multicapa es usada para identificarlo. Usando un análisis tipo Lyapunov, una nueva ley de actualización estable es presentada, además la estabilidad global es probada. Finalmente, se presenta la aplicación de dicha técnica al sistema no-lineal TORA mediante simulaciones.

  13. CLARIFICACIÓN DE AGUAS USANDO COAGULANTES POLIMERIZADOS: CASO DEL HIDROXICLORURO DE ALUMINIO

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    JUAN MIGUEL COGOLLO FLÓREZ

    2011-01-01

    Full Text Available En este artículo se realiza un estudio del proceso de clarificación en sistemas de tratamiento de aguas industriales usando un coagulante inorgánico polimerizado (hidroxicloruro de aluminio. Inicialmente, se establecen los elementos conceptuales más importantes de las etapas del proceso de clarificación (coagulación, floculación y sedimentación. Luego, se señalan los principales coagulantes convencionales utilizados en el tratamiento de aguas y se abordan los policloruros de aluminio (PAC´s como integrantes de una nueva generación de coagulantes alternativos cuyo uso se ha incrementado en las últimas décadas dado su mejor desempeño respecto a los coagulantes convencionales; se especifican los aspectos técnicos y operativos que se deben considerar al momento de implementar un proceso de clarificación de aguas usando un PAC como coagulante. Finalmente, se presentan datos comparativos de condiciones operacionales reales de un proceso de clarificación de aguas, producto de un trabajo previo, donde se remplazó un coagulante convencional (sulfato de aluminio por hidroxicloruro de aluminio, donde se corrobora el mejor desempeño del proceso luego del remplazo.

  14. Sistemas basados en conocimiento usando Prolog

    OpenAIRE

    Zenaida García Valdivia; Isis Bonet Cruz; Maikel León Espinosa; Pedro Y. Piñero Pérez

    2011-01-01

    Se exponen algunos de los resultados alcanzados en la Universidad Central "Marta Abreu" de Las Villas en cuanto al uso de un lenguaje de Programación Lógica (Prolog) en la elaboración de Sistemas Basados en Conocimiento para diferentes áreas del saber como son la medicina, soldadura, educación, sistemas eléctricos de potencia, entre otros. Todos los sistemas elaborados utilizan el paradigma de la programación lógica para la representación del conocimiento de los expertos en los temas en cuest...

  15. Sistemas basados en conocimiento usando Prolog

    Directory of Open Access Journals (Sweden)

    Zenaida García Valdivia

    2011-10-01

    Full Text Available Se exponen algunos de los resultados alcanzados en la Universidad Central "Marta Abreu" de Las Villas en cuanto al uso de un lenguaje de Programación Lógica (Prolog en la elaboración de Sistemas Basados en Conocimiento para diferentes áreas del saber como son la medicina, soldadura, educación, sistemas eléctricos de potencia, entre otros. Todos los sistemas elaborados utilizan el paradigma de la programación lógica para la representación del conocimiento de los expertos en los temas en cuestión y además hacen uso de entornos agradables a los usuarios a través interfaces visuales elaboradas en ambientes de programación para súper lenguajes ó utilizan un conjunto de herramientas para la elaboración de sistemas sobre la Web

  16. Comando de um Servomecanismo usando Visão Computacional

    OpenAIRE

    Ricardo Carneiro Ferreira; João Manuel R. S. Tavares; Francisco Freitas

    2003-01-01

    Neste artigo é apresentada uma metodologia para controlar um servomecanismo usando visão computacional. As imagens de controlo,baseadas na linguagem gestual, são obtidas por intermédio de uma webcam genérica e processadas praticamente em tempo real. Aordem de comando em causa é reconhecida por diferença dos histogramas de orientação da imagem associada e das imagens deordens preestabelecidas. Estas imagens de ordens são guardadas durante o processo de aprendizagem do sistema de controlo. I...

  17. Control adaptable indirecto usando Redes Neuronales Dinámicas

    OpenAIRE

    M. A. Moreno Armendariz; A. S. Poznyak; W. Yuliu

    2001-01-01

    En este trabajo se propone un nuevo tipo de control no-lineal por retroalimentación para una clase de sistemas continuos no-lineales de una entrada y una salida de la siguiente forma: Se supone que el sistema no-lineal es desconocido, así una red neuronal dinámica multicapa es usada para identificarlo. Usando un análisis tipo Lyapunov, una nueva ley de actualización estable es presentada, además la estabilidad global es probada. Finalmente, se presenta la aplicación de dicha técni...

  18. Aplicación de Redes bayesianas usando Weka

    OpenAIRE

    Corso, Cynthia Lorena; Gibellini, Fabián

    2011-01-01

    Este trabajo tiene el objetivo de exponer la aplicación de una técnica de minería de datos como las Redes Bayesianas, aplicadas a la resolución de una problemática relacionada del campo de la ingeniería como lo es el mantenimiento correctivo. En él se expone cual es la problemática y el porqué de la elección de esta técnica para la clasificación de ocurrencias y cuales son los resultados obtenidos de aplicar esta técnica de minería de datos usando software Weka.

  19. Diseño y construccion de un potenciostato para procesos de sintesis de materiales usando electrodeposición química

    OpenAIRE

    Gómez, Diego F.; Rosales-Rivera, Andrés; Gómez-Peña, Alvaro

    2012-01-01

    El presente trabajo se enfoca al diseño y desarrollo de un potenciostato, el cual pueda utilizarse en diferentes áreas incluyendo síntesis de materiales usando electro-deposición química, estudios de procesos de corrosión y pruebas de voltamperometria cíclica. El potenciostato desarrollado es versátil, estable, opera en el rango de micro-amperios y provee un alto rendimiento como el de un potenciostato comercial pero es de menor costo. En la construcción del potenciostato, se utilizaron ampli...

  20. Primera edad U-Pb en circón usando LA-ICP-MS de un dique traquiandesítico emplazado en el granito tipo-A Los Árboles, Sierras Pampeanas Orientales

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    Juan A Dahlquist

    2012-06-01

    Full Text Available La edad de cristalización de diques subvolcánicos emplazados en plutones graníticos carboníferos, Sierras Pampeanas Orientales, permanece incierta. La primera edad U-Pb en circón usando LA-ICP-MS obtenida en un dique que intruye al plutón Los Árboles (sierra de Fiambalá, revela una edad de cristalización de 311 ± 3 Ma.

  1. Estructura y diversidad genética en vacas Holstein de Antioquia usando un polimorfismo del gen bGH

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    Juan Rincon F.

    2013-03-01

    Full Text Available Objetivo. Determinar las frecuencias alélicas y genotípicas del polimorfismo del intrón 3 del gen bGH y estimar algunos parámetros de estructura poblacional en ganado Holstein. Materiales y métodos. El estudio se realizó con 1366 vacas Holstein en 120 hatos de 11 municipios del departamento de Antioquia. Se extrajo DNA por el método de Salting out y la genotipificación se realizó usando la técnica de PCR-RFLPs. La diversidad genética se determinó mediante la comparación de las heterocigosidades, El equilibrio de Hardy-Weinberg (HW y la diferenciación genética entre las poblaciones se realizó usando el software Arlequín 2.0 Las frecuencias alélicas y genotípicas se evaluaron mediante el paquete estadístico SAS®. Resultados. Las frecuencias genotípicas encontradas fueron 0.764 (+/+, 0.223 (+/- y 0.013 (-/- y las frecuencias alélicas 0.876 (+ y 0.124 (-. No se encontraron desviaciones del Equilibrio de Hardy Weinberg en ninguna de las subpoblaciones. La diversidad genética determinada mediante la comparación de las heterocigosidades fue relativamente baja entre poblaciones pero al interior de estas no. El valor de FST de toda la población fue de 0.0068 y significativo (p<0.05, algunos FST pareados también lo fueron, tomando valores desde 0.0 a 0.13. Los estadísticos FIT y FIS no fueron significativos. Conclusiones. El gen bGH es un candidato interesante para evaluar características de importancia económica ya que no parece haber sido sometido a selección directa, presenta una variabilidad media en las poblaciones, observándose diferenciación genética significativa entre distintos municipios, producto de los diferentes sistemas de producción y acceso a las biotecnologías.

  2. Destilación al Vacío de Etanol usando Bomba Chorro

    OpenAIRE

    William Orozco

    2010-01-01

    This paper presents a review and analysis of the literature regarding ethanol production technologies and, the features, dimensions and functioning of jet pumps, which are devices that create a vacuum for distilling ethanol. This review mainly takes into account references from the previous 15 years, both national and international research, which yielded updated information on the use of jet pumps in refrigeration and air conditioning systems and established that, in terms of vacuum distilla...

  3. Destilación al Vacío de Etanol usando Bomba Chorro

    Directory of Open Access Journals (Sweden)

    William Orozco

    2010-12-01

    Full Text Available This paper presents a review and analysis of the literature regarding ethanol production technologies and, the features, dimensions and functioning of jet pumps, which are devices that create a vacuum for distilling ethanol. This review mainly takes into account references from the previous 15 years, both national and international research, which yielded updated information on the use of jet pumps in refrigeration and air conditioning systems and established that, in terms of vacuum distillation of ethanol the best operating conditions and, therefore, the best dimensions and geometry of the jet pump, are obtained for the driving pressure and pressure at the exit nozzle to deliver a 6 kPa vacuum with the greatest entrainment ratio and the highest Mach number at the exit nozzle.

  4. GRINDING OF HARDENED STEELS USING OPTIMIZED COOLING RECTIFICADO DE ACEROS ENDURECIDOS USANDO REFRIGERACIÓN OPTIMIZADA

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    Manoel Cléber de Sampaio Alves

    2008-06-01

    medio. Para ello, al proceso de rectificación está intrínseco el reciclaje del fluido de corte, que se destaca por su costo. A través de la variación de la velocidad de avance en el proceso de rectificación cilíndrica externa del acero ABNT D6, racionalizando la aplicación de dos fluidos de corte y usando una muela superabrasiva de CBN (nitruro de boro cúbico con ligante vitrificado, se evaluaron los parámetros de salida fuerza tangencial de corte, rugosidad, circularidad, desgaste de la herramienta, la tensión residual y la integridad superficial a través de la microscopia electrónica de barrido (SEM de las piezas de prueba. Con el análisis del desempeño fluido, muela y velocidad de inmersión se encontró las mejores condiciones de fabricación propiciando la disminución del volumen de fluido de corte, disminución del tiempo de fabricación sin perjudicar los parámetros geométricos, dimensionales, el acabado superficial y la integridad superficial de los componentes.

  5. Análisis de Singularidades usando la transformada Wavelet

    OpenAIRE

    Giraldo Cuartas, D.; Quintero, O.L.

    2014-01-01

    Existen muchas señales presentes en el medio que describen fenómenos físicos que por si misma naturaleza, son de carácter no diferenciable y medir esta no diferenciabilidad, puede exhibir patrones o características de uno u otro modo no pueden ser detectados por otros medios. Comúnmente, la diferenciabilidad se mide con el exponente de Lipschitz el cual da un criterio cuantitativo de que tan derivable es una señal en un punto, pero hallar este exponente no es fácil. En este trabajo se impleme...

  6. Entorno de Audio usando la nueva API de HTML 5

    OpenAIRE

    LATORRE PLAYÁN, JAVIER

    2015-01-01

    Este trabajo tiene como objetivo el diseño y programación de una aplicación de audio sobre la nueva API de audio de HTML 5. Para ello, utilizamos el programa SoundCool, que es propiedad de la Universidad Politécnica de Valencia y, a partir de los módulos que implementa, los adaptaremos al lenguaje antes mencionado, con el propósito de hacerlo más accesible y atractivo visualmente. Para poder llevar a cabo lo mencionado anteriormente, se ha realizado, en primer lugar, un trabajo de investig...

  7. Desarrollo de un sitio web corporativo accesible usando Drupal

    OpenAIRE

    Pinto Martín, María

    2011-01-01

    En este anexo se recoge la evaluación heurística realizada al antiguo sitio web con las conclusiones obtenidas mediante un análisis cuantitativo de la misma. La evaluación heurística se ha llevado a cabo por el personal del departamento de informática de la empresa y se han tenido en cuenta los factores de frecuencia e impacto para valorar la severidad de cada heurística. Las heurísticas se han agrupado en cuatro grupos con un conjunto de heurísticas cada uno de ellos. Esta evaluación está ...

  8. Esquema de redundancia y distribución de carga de alta disponibilidad para la prestación de telefonía ip usando sip (junio 2009)

    OpenAIRE

    PARRA L., ANDRÉS; Guerrero, Fabio G.

    2010-01-01

    En este artículo se presenta un esquema de distribución de carga y redundancia en la infraestructura de un ISP (Internet Service Provider) para la prestación de servicios de telefonía IP (ITSPs) sobre Internet usando el protocolo SIP (Session Initiation Protocol) garantizando niveles de acceso al servicio similares a la PSTN (Public Switched Telephone Network) y brindando una infraestructura de red escalable. La solución se plantea en tres partes: redundancia del servicio y distribución de ca...

  9. Identificación de hojas de plantas usando Vectores de Fisher

    OpenAIRE

    Redolfi, Javier A.; Sánchez, Jorge Adrián; Pucheta, Julián Antonio

    2015-01-01

    En este trabajo se propone el uso de descriptores locales codificados con el método de Vectores de Fisher para resolver el problema de clasificación de hojas de plantas usando imágenes. Se demuestra que con este enfoque se obtienen resultados de estado del arte en conjuntos de datos públicos, sin la necesidad de recurrir a la creación de nuevos descriptores visuales específicos para el problema, ni la necesidad de realizar ningún preprocesamiento de las imágenes a analizar.

  10. Un estudio de la covariación con profesores universitarios usando tecnología

    OpenAIRE

    Valero, María del Socorro; Barba, Ma. Guadalupe; Ventura, María Paulina; Del Castillo, Alejandro; Torres, María José

    2010-01-01

    En el presente estudio se analizaron las producciones de 13 profesores universitarios relacionadas con 4 enunciados verbales referidos a la rapidez de variación, antes y después de que desarrollaran actividades de laboratorio usando tecnología de calculadoras graficadoras y sensores de parámetros físicos diversos para obtener y analizar, gráficas cartesianas generadas en tiempo real, durante un curso de 30 horas. El objetivo de esta experiencia fue dotar a los docentes universitarios de eleme...

  11. Comando de um Servomecanismo por Linguagem Gestual usando Visão Computacional

    OpenAIRE

    Ricardo Ferreira; João Manuel R. S. Tavares; Francisco Freitas

    2003-01-01

    Neste artigo é apresentada uma metodologia para controlar um servomecanismo, por linguagem gestual, usando visão computacional. As imagens de controlo são obtidas por intermédio de uma webcam genérica e processadas praticamente em tempo real. A ordem de comando em causa é reconhecida por diferença dos histogramas de orientação da imagem associada e das imagens de ordens preestabelecidas. Estas imagens de ordens são guardadas durante o processo de aprendizagem do sistema de controlo. In thi...

  12. Modelación de eventos extremos usando la distribución Dagum.

    OpenAIRE

    Sexto Monroy, Benjamín

    2011-01-01

    En el presente trabajo se implementa la modelación de valores extremos con la metodolog ía "block maxima", específicamente en niveles m áximos diarios de ozono de la estaci ón Pedregal de la Cd. de M éxico de los años 2001 a 2008, usando la distribución Dagum que es de cola pesada y es usada generalmente como distribuci ón de ingreso, pero tiene un antecedente en el campo meteorol ógico, donde fue usado para modelar la cantidad de precipitaci ón pluvial. Una visualizaci ón general ...

  13. Implementación de una memoria asociativa lineal usando el lenguaje r

    OpenAIRE

    Velásquez, J uan D.

    2011-01-01

    Como un aspecto fundamental en muchos cursos de redes neuronales artificiales, el desarrollo de destrezas de programación es un objetivo fundamental. Este artículo tiene dos objetivos: el primero es presentar el lenguaje R para el cómputo estadístico como una poderosa herramienta para ejemplificar algoritmos, para ejecutar cálculos numéricos, y para ilustrar conceptos usando gráficos complejos. El segundo objetivo es ilustrar la implementación práctica de un modelo de redes neuronales en el l...

  14. Hacia la validación de arquitecturas de software usando Alloy

    OpenAIRE

    Novaira, Maria Marta; Permigiani, Sonia

    2005-01-01

    En este trabajo, presentamos algunas líneas de trabajo que seguimos actualmente, con el objetivo principal de utilizar el lenguaje relacional Alloy para la validación de propiedades estáticas y dinámicas de arquitecturas de software. Allor es un lenguaje de especificaciones con una semántica formal clara, basada principalmente en la noción de relación, y que ha ganado importancia en el último tiempo. Presentamos aquí de qué forma pueden especificarse usando Alloy algunos conceptos asociados a...

  15. Diseño de circuitos integrados analógicos usando la terminal de body en transistores MOS

    OpenAIRE

    Thomas Erviti, Gonzalo

    2014-01-01

    El objetivo del presente trabajo fin de master es el diseño analógico de circuitos integrados CMOS usando la terminal de body en los transistores MOS. Así, se realizará una revisión de las técnicas modernas de diseño, caracterización y análisis, así como la posterior aplicación a diversos sistemas usando estos dispositivos como elemento. Se propondrán nuevas celdas usando esta técnica, las cuales son validadas por resultados de simulación, análisis teóricos y resultados experimentales...

  16. Verificación de Firmas Usando Transformada de Gabor Signature Verification using the Gabor Transform

    Directory of Open Access Journals (Sweden)

    C Cruz

    2004-01-01

    Full Text Available Este artículo se propone un sistema de verificación estática de firmas con alta capacidad de detección de falsificaciones. En la etapa de extracción de características se obtienen los coeficientes de la transformada de Gabor en cada región de la firma, extrayéndose la posición del coeficiente sobresaliente de cada región. Estas proporcionan información local acerca de la frecuencia y orientación de la textura de una firma. Usando las características extraídas, el sistema entrena una red neuronal de retropropagación con una arquitectura de 9-9-2 para cada firmante. La eficiencia del sistema propuesto se evaluó usando 30 firmas auténticas y 20 firmas falsificadas por expertos para cada firmante. De los resultados obtenidos por simulación, se concluye que el sistema propuesto presenta una verificación global con 90% de acierto, con una menor complejidad computacionalThis paper proposes an off-line signature verification system with fairly good detection capacity against expert forgeries. The feature extraction stage of the proposed system, estimates the coefficients of the Gabor Transform in each local region of the signature image, and extracts the positions of relevant coefficients. These provide local information about frequency and orientation of the signature image texture. Using the extracted features, the proposed system adapts a back-propagation multiplayer neural network with 9-9-2 architecture for each signer. The proposed system was evaluated using 30 genuine signatures and 20 expert forgeries for each signer. The computer simulation results show a 90% overall success, with a lower computational complexity

  17. Miedo al crimen en estudiantes de la ciudad de Caracas

    OpenAIRE

    Jan Liebnitzky; Maritza Montero

    2013-01-01

    Se midió el miedo al crimen en un grupo de estudiantes universitarios, centrándose en inseguridad subjetiva y paradoja victimización-miedo, que considera que la inseguridad subjetiva no refleja a la objetiva. Se buscaba saber si esa paradoja existía en los estudiantes y si las teorías explicativas serían útiles. Se comparó el nivel de miedo al crimen con dos ciudades Latinoamericanas, empleando un diseño de secciones-cruzadas, usando el Cuestionario de Inseguridad Urbana, y elementos cuantita...

  18. Cirurgia de revascularização do miocárdio usando apenas tomografia computadorizada como angiograma pré-operatório Cirugía de revascularización del miocardio usando sólo tomografía computada como angiograma preoperatorio Coronary artery bypass using only computed tomography as pre-operative angiogram

    Directory of Open Access Journals (Sweden)

    Diego Felipe Gaia

    2009-09-01

    Full Text Available A cirurgia de revascularização do miocárdio (CRM é um procedimento bem estabelecido com indicações atuais precisas. O advento e a disseminação dessa técnica foram possíveis após a introdução do angiograma coronário. Embora muitos métodos de avaliação tenham evoluído nos últimos anos, nenhum conseguiu substituir o angiograma coronário invasivo como exame pré-operatório. A tomografia computadorizada (TC emergiu como uma alternativa ao angiograma coronário invasivo. O presente relato descreve dois casos de CRM realizadas usando-se apenas a TC como técnica de avaliação anatômica das artérias coronárias pré-operatória.La cirugía de revascularización del miocardio (CRM es un procedimiento bien establecido con indicaciones actuales precisas. El advenimiento y la divulgación de esta técnica fueron posibles después de la introducción del angiograma coronario. Aunque muchos métodos de evaluación hayan evolucionados en los últimos años, ninguno ha conseguido sustituir al angiograma coronario invasivo como examen preoperatorio. La tomografía computada (TC surgió como una alternativa al angiograma coronario invasivo. El presente informe describe dos casos de CRM realizadas usando sólo la TC como técnica de evaluación anatómica de las arterias coronarias preoperatoria.Coronary artery bypass graft (CABG is a well established procedure with current precise indications. The advent and spread of this technique was possible after the introduction of the coronary angiogram. Although many evaluation methods have been developed in the past years, to date, none have been able to replace the invasive coronary angiogram as a pre-operative exam. Computed tomography angiography (CTA has emerged as an alternative to invasive coronary angiogram. In this report we describe two CABG cases that were performed using only this technique as a pre-operative anatomic coronary arteries evaluation.

  19. Variabilidad genética de Aedes aegypti en algunas áreas del Perú usando Single Stranded Conformational Polymorphism (SSCP

    Directory of Open Access Journals (Sweden)

    Nélida Leiva G

    2004-07-01

    Full Text Available Aedes aegypti es el vector responsable de la transmisión del virus del dengue, su distribución geográfica se ha ampliado rápidamente debido principalmente a la intervención de los seres humanos. Objetivo: Analizar la variabilidad genética de este mosquito mediante la comparación del Segundo Espaciador Transcrito Interno (ITS 2 perteneciente al ADN ribosomal (rADN. Materiales y Métodos: Se analizaron muestras de ocho localidades (Jaén, Tingo María, Iquitos, Lambayeque, el distrito de El Rimac, Sullana y Zarumilla y uno de la provincia de Huaquillas (Ecuador. El análisis de la variabilidad se determinó usando la técnica conocida como SSCP (Single Stranded Conformation Polymorphism. Resultados: El estudio muestra que existe variabilidad genética entre las poblaciones analizadas, principalmente entre las muestras localizadas en la costa del Perú (Zarumilla, El Rímac, Sullana y Huaquillas y las muestras del nororiente (Tingo María, Iquitos, Jaén y Lambayeque Conclusión: Se determinaron dos variantes genéticas entre las poblaciones de Aedes aegypti: Costeña y Nororiental, que probablemente provienen de dos ancestros diferentes y cuyo ancestro común sufrió de aislamiento por distancia. Se observó que no existe relación entre las distancias genéticas y las distancias geográficas indicando que la migración de estas poblaciones es el resultado de la intervención de los seres humanos que diseminan al vector y no por la migración activa del mosquito. Se plantea el papel de la Cordillera de los Andes en la migración y separación de las poblaciones de Aedes.

  20. Estimación de parámetros genéticos para características de crecimiento en borregos Katahdin usando diferentes modelos

    Directory of Open Access Journals (Sweden)

    Coralia Inés V. Manzanilla Pech

    2012-01-01

    Full Text Available Se estimaron parámetros genéticos para características de crecimiento en corderos Katahdin, usando seis variantes del modelo animal. Se usó información de pesos al nacimiento (BW; n= 13,099, al destete ajustado a 75 d (WW; n= 11,509 y posdestete ajustado a 120 d (AW; n= 6,886 tomada durante 7 años (2004-2010 en 20 estados de la República Mexicana. Los análisis se hicieron ignorando o incluyendo efectos maternos. El modelo más sencillo incluyó el efecto genético aditivo directo como el único efecto aleatorio. El modelo más completo incluyó los efectos genéticos directo y materno, la covarianza entre ellos, y el efecto del ambiente permanente materno. Para seleccionar el mejor modelo se usó la prueba de razón de verosimilitud. Cuando los efectos maternos no fueron incluidos en el modelo, los estimadores de la heredabilidad directa y de la varianza genética directa resultaron sobreestimados. Las heredabilidades directas con el mejor modelo fueron 0.18 ± 0.03, 0.30 ± 0.04 y 0.20 ± 0.05 para BW, WW y AW, respectivamente. Las heredabilidades maternas también variaron dependiendo del modelo, de 0.05 a 0.23, 0.00 a 0.12, y 0.09 a 0.25 para BW, WW y AW. El ignorar los efectos maternos en el modelo resultaría en una evaluación genética equivocada para las características de crecimiento en borregos Katahdin.

  1. Evaluación de la reducibilidad de un mineral de hierro usando char como reductor

    Directory of Open Access Journals (Sweden)

    Yenny Rubiela Hernández, Carlos Alberto Sandoval Fonseca, Claudia Inés Sánchez Buitrago

    2011-05-01

    Full Text Available Muestra los ensayos de  reduciblidad  realizados en un hornotipo Linder a un mineral de hierro del municipio de Ubalá(departamento de Cundinamarca, Colombia, usando comoreductor un char. Se  indican las características del mineralde  hierro  de Ubalá, de  los  carbones  empleados para  laproducción del char y de la caliza, así como los ensayos dereducibilidad. Para la caracterización de  las materias primasy del char, como producto  final, se aplicaron normas ASTM.En  la producción de  los char se utilizaron  los hornos decoquización  tipo Cerchar  y  tipo  colmena  de  la Uptc  enSamacá  (Boyacá. Los ensayos de reducibilidad se hicieronbajo  los mismos parámetros de operación utilizados concarbón como reductor, y los resultados obtenidos dejan verque el mineral de hierro de Ubalá es reducible en menorporcentaje con char. Sin embargo, por  los grandes beneficiospara el medioambiente que se obtienen trabajando con elchar, no se descarta  la posibilidad de utilizarlo como posiblesustituto del carbón en el proceso de reducción directa.

  2. Materiales de Al2O3 - MgAl2O4 - CaAl12O19 - Ca2Mg2Al28O46 obtenidos mediante un proceso de sinterización reactiva entre Al2O3 y CaMg(CO3)2

    OpenAIRE

    Aza Moya, Antonio H. de; Peña, P.; Moset, M.

    2002-01-01

    [ES] Utilizado la información suministrada por el diagrama de equilibrio de fases Al2O3-MgO-CaO se ha diseñado y obtenido un material de Al2O3-MgAl2O4-CaAl12O19-Ca2Mg2Al28O46 mediante sinterización reactiva de una mezcla de Al2O3 y CaMg(CO3)2. Las reacciones que tienen lugar en la mezcla durante el proceso se han estudiado usando técnicas de análisis térmico diferencial, termogravimetrico y dilatometría. Muestras reaccionadas a temperaturas seleccionadas se han estudiado por difracci...

  3. IMPLEMENTACIÓN DE UN SERVICIO EN LA WEB –MASHUP– PARA LA FUSIÓN DE IMÁGENES SATELITALES USANDO LA TRANSFORMADA RÁPIDA DE WAVELET HAAR

    Directory of Open Access Journals (Sweden)

    Rubén Medina

    2014-05-01

    Full Text Available En este artículo se implementa un nuevo servicio en la Web que ofrece a los usuarios la posibilidad de realizar la fusión de imágenes de satélite provenientes de diferentes sensores remotos y/o con diferentes resoluciones espaciales. A lo largo del artículo tres temáticas importantes son abordadas. La primera temática corresponde al servicio Web, éste servicio es implementado usando software libre y cuenta con una sencilla interfaz donde el usuario puede interactuar y principalmente puede realizar una solicitud del servicio de fusión. Adicionalmente, en la aplicación Web se desarrolló un módulo que permite obtener datos georreferenciados de diferentes fuentes externas para crear un nuevo servicio (Mashup a través de las API’s, de manera rápida y fácil utilizando OpenStreetMaps. La segunda temática se ocupa del análisis de la transformada rápida de wavelet haar (TRWH, estos conceptos matemáticos se abordan a partir de un ejemplo usando una matriz que se descompone en coeficientes de detalle y de aproximación de segundo nivel. La última temática detalla la metodología propuesta, paso a paso, para realizar la fusión de imágenes usando la TRWH. Igualmente con el fin de determinar la eficiencia de la TRWH cinco wavelets diferentes fueron implementadas en Matlab para fusionar el mismo par de imágenes satelitales. Las imágenes resultantes fueron evaluadas tanto en la calidad espacial como en la espectral a través de cuatro índices. Los mejores resultados de la evaluación fueron obtenidos con la TRWH la cual preserva la riqueza espectral de la imagen multiespectral original y mejora su calidad espacial.

  4. ALS Association

    Science.gov (United States)

    ... toward a world without ALS! Walk to Defeat ALS® Walk to Defeat ALS® draws people of all ... We need your help. I Will Advocate National ALS Registry The National ALS Registry is a congressionally ...

  5. Un estudio sobre el desarrollo del pensamiento aleatorio usando recursos educativos abiertos

    Directory of Open Access Journals (Sweden)

    Yenny Patricia Pinzón Triana

    2015-04-01

    Full Text Available Este estudio presenta los resultados de un proyecto de investigación sobre la implementación de la enseñanza probabilística con recursos educativos abiertos (REA, diseñados en la plataforma Edmodo, y que está dirigido a estudiantes de tercer grado de educación básica secundaria de Bogotá, Colombia, y Tuxtepec, México. El fin era evidenciar sus preconceptos, nociones y evaluar el resultado de la instrucción en términos de su pensamiento probabilístico y dar respuesta a la interrogante ¿cuál es el efecto de la instrucción en probabilidad usando Edmodo en estudiantes de tercer grado de educación básica secundaria respecto a la valoración de fenómenos aleatorios de la vida cotidiana, sus conjeturas y la toma de decisiones? Se empleó un enfoque cualitativo a partir del método de estudio de casos, desde el análisis particular a lo general (Stake, 2005. Para la implementación, se consideró el estudio de Fishbein (1975 sobre el desarrollo del pensamiento probabilístico y el de Marzano (2000, relacionado con las dimensiones del aprendizaje. Estos elementos sirvieron para establecer el impacto del uso de los REA, en especial el de la plataforma Edmodo en el desarrollo de competencias en los estudiantes. Los instrumentos consistieron en una prueba de entrada, actividades de apoyo interactivo desde Edmodo y una prueba de salida para determinar los niveles de aprendizaje; mediante triangulación de datos, se evidenciaron alcances de niveles adecuados de desempeño acordes con los requerimientos de los estándares nacionales e internacionales.

  6. Pirólise catalítica do PEBD usando como catalisador a vermiculita modificada

    Directory of Open Access Journals (Sweden)

    Franciel Aureliano Bezerra

    2016-01-01

    Full Text Available Resumo O polietileno de baixa densidade (PEBD é um dos polímeros mais usados atualmente, e a grande quantidade desse polímero produzida resulta em toneladas de resíduos, que necessitam ser tratados. Neste trabalho foi realizada a pirólise termocatalítica do PEBD usando como catalisador a argila vermiculita modificada, como alternativa para o tratamento dos resíduos. A argila foi tratada com solução de ácido nítrico a diferentes concentrações e calcinada a 400 °C. Os materiais foram caracterizados por técnicas de difratometria de raios X, termogravimetria, adsorção de nitrogênio e espectroscopia de energia dispersiva. A pirólise térmica e termocatalítica foi realizada em um micro reator acoplado com GC/MS, a 500 °C. O intuito da pirólise de resíduos poliméricos é a obtenção de hidrocarbonetos leves (C<16, que possam ser empregados na indústria química e petroquímica, através de quebras na cadeia polimérica. Os resultados foram satisfatórios, com aumento no rendimento para hidrocarbonetos leves ao empregar os catalisadores chegando a 71,4% de produtos com C<16, enquanto a pirólise térmica resultou apenas de 25,8%.

  7. AUTOMATIZACIÓN DE LA ARQUITECTURA DE COMPONENTES GENÉRICOS USANDO UML

    Directory of Open Access Journals (Sweden)

    Noel Fuentes Ramírez

    2006-04-01

    Full Text Available

     

    La arquitectura de componentes genéricos permite chequear la consistencia interna de sus elementos arquitectónicos (componentes y conectores a partir de las relaciones internas en sus respectivas estructuras, que pueden ser de inclusión y transformación. También permite verificar la conexión entre componentes y conectores a partir de las relaciones de transformación entre sus interfaces respectivas. Las ideas que se presentan aquí constituyen una propuesta para la automatización de la descripción de esta arquitectura usando el lenguaje de modelado unificado (UML a partir de la descripción formal de sus diagramas de clases y de secuencia, así como para el chequeo de la consistencia. En este artículo se muestra la aplicación de esta propuesta mediante una extensión de la herramienta Visual Paradigm, por medio de un módulo de software conectable.

  8. Técnicas de Marca de Agua para Video MPEG usando Sensibilidad Visual y Vectores de Movimiento Video Watermarking Technique using Visual Sensibility and Motion Vector

    Directory of Open Access Journals (Sweden)

    Antonio Cedillo

    2008-01-01

    Full Text Available Se propone un algoritmo de marca de agua para video digital, en donde la inserción y detección de la marca de agua se realiza durante el proceso de codificación MPEG-2. La señal de marca de agua esta incrustada en los coeficientes de DCT en el canal azul de los cuadros I y P del video MPEG. La energía de la marca de agua se calcula usando la sensibilidad visual de los cuadros (I y P y la magnitud de los vectores de movimiento en los cuadros de P. Los resultados de simulación computacional muestran la imperceptibilidad de marca de agua, obteniendo un PSNR mayor a 45dB, conservando la robustez de la misma cuando es sometida a diversas distorsiones, tales como contaminación por ruido, recorte, y eliminación de cuadros, entre otros. El algoritmo propuesto tiene una influencia mínima en la velocidad del proceso de codificación MPEG.A video watermarking algorithm, in which watermark embedding and detection process are carried out during the MPEG-2 coding process is proposed. The watermark signal is embedded in the DCT coefficients of blue channel of I-frames and P-frames. The embedding energy is computed adaptively using perceptual information of the I-frames and the P-frames, and motion vectors information in the P-frame. Computer simulation results show the watermark imperceptibility, obtaining a PSNR greater than 45 dB and maintaining its robustness to common signal distortions such as contamination by noise, cropping, frame dropping, frame swapping and frame averaging, among others. The proposed algorithm has very little influence on the MPEG decoding speed.

  9. Implementación de un controlador borroso usando técnicas de PWM analógico

    OpenAIRE

    Tombs, J. N.; García Franquelo, Leopoldo; Torralba Silgado, Antonio Jesús

    2009-01-01

    Hoy día la mayoría de los sistemas de control borroso se implementan en software usando procesadores y micro controladores digitales. Los diseños digitales programables son capaces de resolver muchos problemas de control, pero en sistemas de tiempo real, donde las señales de control tienen que cambiar en solo unos ciclos del reloj, la implementación hardware es la única solución posible. En este artículo se presenta un diseño de VLSI hardware, basado en técnicas de diseño analógicas usan...

  10. Construcción de un modelo de secador de yuca, en medio poroso, usando flujo radial de aire caliente

    Directory of Open Access Journals (Sweden)

    Néstor Durango

    2004-01-01

    Full Text Available Este artículo presenta el diseño y fabricación de un secador radial de yuca, en lecho poroso, usando energía eléctrica como fuente de calentamiento del aire de secado. Se presentan las pruebas llevadas a cabo en el secador con el fin de analizar su desempeño energético, la tasa de remoción de humedad en función del tiempo y las temperaturas de operación del mismo

  11. Optimización del tratamiento de aguas residuales de cultivos de flores usando humedales construidos de flujo subsuperficial horizontal

    OpenAIRE

    Mónica L. Jaramillo-Gallego; Ruth M. Agudelo-Cadavid; Gustavo A Peñuela-Mesa

    2016-01-01

    Resumen Objetivo: optimizar un sistema de tratamiento de aguas residuales de cultivos de flores, con el fin de mejorar la eficiencia en la remoción de los contaminantes, usando humedales construidos de flujo subsuperficial-horizontal. Metodología: se realizó un estudio de tipo exploratorio experimental en dos etapas, en la primera se efectuó el acondicionamiento fisicoquímico y biológico del sistema de tratamiento, en la segunda, se llevó a cabo el seguimiento de la remoción de los contami...

  12. DIGESTÃO DE CARBOIDRATOS USANDO DIGESTIVOS ENZIMÁTICOS COMERCIAIS – UMA AULA PRÁTICA.

    OpenAIRE

    Maria Teresa Pedrosa Silva Clerici; Roberval Serafim da Silva; Armindo Antonio Alves

    2006-01-01

    Este trabalho mostra uma aula prática na qual se estuda a digestão decarboidratos “in vitro” utilizando amido gelatinizado como substrato e doismedicamentos comerciais indicados para problemas digestórios, como fonte deamilase. As reações enzimáticas foram feitas no equipamento dissolutor a 37º C, comagitação constante e usando meios que simulavam o pH do estômago e em seguida opH do intestino delgado. Para avaliar a eficácia das enzimas pancreáticas nosdigestivos, foi feita uma reação com am...

  13. Aptitud combinatoria general y especifica de líneas tropicales de maiz usando probadores

    Directory of Open Access Journals (Sweden)

    Mauro Sierra

    2000-01-01

    Full Text Available Aptitud combinatoria general y específica de líneas tropicales de maíz usando probadores. Durante el ciclo O - I 1996/97 fueron evaluados en el Campo Experimental Cotaxtla mestizos de líneas sobresalientes y provenientes de varias fuentes de germoplasma como son : a Líneas recicladas de H-513 X VS-536, b Líneas derivadas de un compuesto de amplia base genética, c Líneas élite de programa de maíz de Cotaxtla (LTs y d Líneas de CIMMYT (CMLs. Como probadores se usaron las líneas LT-154 y LT-155 progenitores del híbrido H-513 y las líneas CML247 y CML254 cuya cruza es un patrón heterótico definido por CIMMYT para el trópico. Hubo líneas con buen comportamiento per-se tanto en rendimiento como en características agronómicas y que se encuentran formando mestizos sobresalientes con uno o varios probadores. Con relación a la Aptitud combinatoria, se encontró que las líneas F31XF30-4-3-1, F41XF40-1-2-1, CABG3’-12-2-1-2-1-1, LT174 y CML15 registraron los máximos valores con el probador 2 (LT155; F4XF3-5-2-1 y CML15 con el probador 4 (CMl254. Así también, las líneas F4XF5-5-1-1, y CABG3’-12-2-1-2-1-1, LT174, CML13 y CML15 con buena ACG. Con relación a los probadores, se encontró que para el grupo de líneas Recicladas , los probadores 1(LT154 y 4 (CML254 registraron los coeficientes de regresión más altos, lo que indica que permiten identificar líneas sobresalientes. Para líneas CABG fué el probador 2 (LT155 el que registró el mejor valor y en líneas Élite , los probadores 2(LT155, y 3(CML247 identificaron mejor a las líneas sobresalientes. Para las líneas del CIMMYT el mejor valor fué para el probador 4(CML254

  14. "Making Cambios, Usando la Voz": Addressing Ethical Dilemmas of Education in Immigrant Contexts

    Science.gov (United States)

    Zarate, Adanari D.; Reese, Leslie; Flores, David; Villegas, Jisel

    2016-01-01

    The growing population of immigrant youth in the United States includes both documented and undocumented young people, as well as those who live in mixed status families in which some family members are authorized and at least one other family member is not (Suárez-Orozco, et al., 2011). These young people find themselves residing at the center of…

  15. Caracterización de materiales usando propagación ultrasónica

    OpenAIRE

    Montero De Espinosa Freijo, Francisco

    2000-01-01

    PACS:43.38.-p, 43.35.-c.-- Publicado en el Vol. XXXI, núm. 3-4, tercer y cuarto trimestre 2000 de la Revista de Acústica: Número especial dedicado al XXV Aniversario del Instituto de Acústica del C.S.I.C.

  16. Análisis de parámetros heredables asociados al rendimiento y precocidad en arveja voluble (pisum sativum l.) tipo santa isabel

    OpenAIRE

    Ligarreto, Gustavo

    2010-01-01

    En el mejoramiento del cultivo de arveja es importante estimar los factores heredables que, asociados al rendimiento y la precocidad de los diferentes materiales, tienden a incrementar la productividad. Para tal efecto, en la Sabana de Bogotá se realizó el presente estudio durante un ciclo de producción en condiciones de invernadero. Se emplearon 10 materiales de arveja en diferentes generaciones filiales, usando como parentales los cultivares Santa Isabel (SI), San Isidro (SAI), Diacol Calda...

  17. Short run hydrothermal coordination with network constraints using an interior point method Coordinación hidrotérmica de corto plazo con restricciones de red usando un método de punto interior

    Directory of Open Access Journals (Sweden)

    Jesús María López Lezama

    2008-12-01

    Full Text Available This paper presents a lineal optimization model to solve the hydrothermal coordination problem. The main contribution of this work is the inclusion of the network constraints to the hydrothermal coordination problem and its solution using an interior point method. The proposed model allows working with a system that can be completely hydraulic, thermal or mixed. Results are presented on the IEEE 14 bus test system.En este artículo se presenta un modelo de optimización lineal para resolver el problema de la coordinación hidrotérmica. El principal aporte de este trabajo es la inclusión de las restricciones de red al problema de coordinación hidrotérmica y su solución usando un método de punto interior. El modelo propuesto permite manejar un sistema completamente hídrico, completamente térmico o un sistema mixto. Se presentan resultados para el sistema de prueba IEEE de 14 barras.

  18. Solución a un problema estático en un área con topografía abrupta usando una velocidad de reemplazamiento variable

    Directory of Open Access Journals (Sweden)

    Castillo López Luis Antonio

    2002-08-01

    calculate with variable velocity is proposed.

    This method have been development in the processing data in areas with irregular surface. For instance, Piedemonte Llanero. The software calculation is ProMAX, algorithm Gauss-Sediel.

    Teniendo en cuenta que para poder obtener una buena imagen del subsuelo, es necesario que las soluciones estáticas sean las mas acertadas posibles en la etapa inicial del procesamiento, y no gastar tiempo en ensayos con procesos mas sofisticados, sin tener resuelto el problema estático, se propone implantar un método de procesamiento usando un modelo de velocidad de reemplazamiento variable en el cálculo de la solución estática. Se pretende explicar que el valor de la velocidad de reemplazamiento influye notoriamente en la imagen de la estructura, la cual puede verse deformada en gran magnitud. Tambien puede ser cuestionado cómo ha sido asignado este valor de manera constante en los proyectos, dando más importancia al amarre con áreas cercanas que a la solución misma del problema estático.

    Se mostrara un estudio en que se emplea una serie de datos reales procesados a partir de un modelo de velocidad de reemplazamiento variable y otra con un modelo de velocidad constante, las que -al ser comparadas y analizadas- dan como resultado grandes contrastes en las imageries obtenidas.

    Este método se ha ido desarrollando durante el procesamiento de

  19. Una experiencia de aula usando matemáticas en la publicidad

    OpenAIRE

    Díaz-Levicoy, Danilo

    2012-01-01

    La matemática es una de las ciencias que presta ayuda al bienestar del hombre y de la sociedad. En este ámbito, la publicidad se ve enormemente beneficiada, pues una gran parte de los anuncios que se muestra en los medios de comunicación hacen clara referencia a descuentos, operaciones aritméticas e incluso a contenidos matemáticos no tan comunes. Este artículo muestra las producciones de alumnos del Colegio Proyección Siglo XXI de Osorno – Chile, relativas a la creación de publicidad con ...

  20. Aplicación Web de bases de datos usando el Framework Ruby on Rails

    OpenAIRE

    BAUTISTA PERALES, ISMAEL

    2014-01-01

    Este proyecto está enfocado a la venta online de libros para estudiantes de la ETSINF en la UPV. En esta aplicación web se pueden hacer reservas de libros, dar de alta nuevos ítems en la base de datos accediendo como usuario administrador, gestionar los usuarios de administración y gestionar los pedidos. Además, la aplicación envía correo electrónico al usuario que decida comprar uno o varios de los ejemplares. Cómo último dato, esta aplicación está internacionalizada (i18n), tanto en inglés ...

  1. Visualizador 3D para dados de radar meteorológico usando WEBGL

    OpenAIRE

    Oliveira Junior, Abimael Alves de

    2013-01-01

    Resumo: A previsão de tempo tem exercido um importante papel na prevenção de perdas de vidas e de bens materiais devido a alagamentos, inundações ou desmoronamentos causados por eventos severos tais como chuvas intensas ou tempestades. Porém as ferramentas de visualização de dados de Radar Meteorológico são bidimensionais, ou seja, apresentam os dados de forma planar. Além disto, as ferramentas tem necessidade de instalação e muitas vezes, são desenvolvidas para Sistemas Operacionais específi...

  2. DESARROLLO DE UN SISTEMA DE NEURO-MERCADOTECNIA USANDO EL DISPOSITIVO EMOTIV-EPOC

    Directory of Open Access Journals (Sweden)

    Luz Ángela Moreno

    2014-11-01

    Full Text Available Este artículo presenta los avances concebidos en la realización de un sistema de neuro-mercadotecnia. El objetivo del sistema es permitir evaluar las emociones que presentan los televidentes al observar comerciales publicitarios. Se hace uso de la interfaz cerebro-computador Emotiv-EPOC para la adquisición de las neuro-señales. Se describen los algoritmos empleados para el análisis de las pautas publicitarias. Se presentan unas pruebas experimentales donde se comparan los resultados obtenidos por métodos tradicionales con las propuestas.

  3. Computo en paralelo para integrales multicéntricas usando una distribución balanceada

    OpenAIRE

    Rosso, Ana; Denner, Claudia; Fraschetti, Guillermo; Tardivo, María Laura; Pérez, Jorge E.; Cesco, Juan

    2013-01-01

    La aproximación del campo autoconsistente (SCF) es utilizada en Quí mica Computacional para abordar problemas de Química Cuántica. Entre otros, la energía molecular y la geometría de equilibrio son elementos determinados al nivel SCF. El enfoque SCF-LCAO presenta complejidad computacional, pues requiere gran esfuerzo de cálculo. Hemos desarrollado un programa secuencial, que posee características interesantes desde el punto de vista numérico, pero con alto costo en tiempo computacional. Con ...

  4. Mejoramiento de la productividad en una industria maderera usando incentivo remunerativo

    OpenAIRE

    Aviles Palacios, M. Carmen; Pino-Pinochet, Patricio; Ponce-Donoso, Mauricio; Vallejos-Barra, Oscar; Abad Balboa, Tomás

    2014-01-01

    Se estudió el efecto en la productividad de la elaboración de blanks a partir de la implementación de un modelo de incentivo salarial del tipo Improshare, dirigido al personal de una empresa chilena de remanufacturado de maderera que produce molduras y marcos de puerta (ayudante, operador medio y operador máster), para lo cual se compararon dos periodos de tiempo, antes (19 meses) y después (21 meses) de la implementación de la política de incentivo. Los resultados mostraron diferencias estad...

  5. Diseño y puesta en marcha de un "sistema semicontinuo en dos etapas: hidrólisis • fermentación" para la producción de etanol a partir de almidón de papa usando simultáneamente Aspergillus nigery Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Amleto León Téllez

    2010-07-01

    Full Text Available Se describe el diseño y evaluación de las variables que gobiernan el sistem semicontinuo en dos etapas: hidrólisis fermentación para la producción de etanol a partir de almidón de papa usando simultáneamente Aspergillus niger y Saccharomyces cerevisiae, con resultados comparables a los del método clásico de monocultivo pero con tiempos de bioproducción inferiores. La hidrólisis del almidón y posterior fermentación produjo cantidades significativas de biomasa, azúcares simples, y enzimas como productos colaterales al etanol.

  6. Aproximándose al “Link perdido”: pointing y lenguaje como intencionalidad compartida.

    OpenAIRE

    Ernesto E. Guerra; Allison F. Smith

    2008-01-01

    Los humanos se comunican a través de un sistema distinto a otros seres vivos. Este artículo tiene como objetivo responder dos preguntas fundamentales sobre este sistema, el lenguaje humano; 1) ¿qué es lo que hace al lenguaje humano tan diferente de otras formas de comunicación? y 2) ¿qué nos ha llevado a desarrollar un sistema tan particular? Usando evidencia teórica y empírica, mostraremos como el lenguaje humano es único, ya que es una parte intrínseca de las habilidades cognitivas, y ya qu...

  7. Distribución de espacios en plantas industriales usando búsqueda tabú

    Directory of Open Access Journals (Sweden)

    CARLOS ANDRÉS DOMÍNGUEZ GUAL

    2005-01-01

    Full Text Available En el problema de la distribución de espacios en plantas industriales se pretende ubicar de forma óptima los departamentos de acuerdo con sus necesidades. Este es un problema complejo de optimización combinatoria debido al gran número de distribuciones posibles, y para cuya solución han sido propuestos varios algoritmos heurísticos; no obstante, dichas técnicas de solución exploran parcialmente y de forma limitada el espacio de posibles combinaciones. Como una alternativa de solución a este problema, se presente una adaptación del método de Búsqueda Tabú, la cual realiza una exploración heurística de mayor amplitud que los métodos tradicionales. Los resultados obtenidos para los casos de aplicación presentados, indican que la metodología propuesta puede encontrar distribuciones de calidad superior, o al menos igual, a los métodos tradicionales.

  8. Monitorização de transplante cardíaco usando análises do eletrograma intracavitário

    Directory of Open Access Journals (Sweden)

    BROFMAN Paulo Roberto S.

    1997-01-01

    Full Text Available Uma série de registros do eletrograma intracavitário tem sido utilizada para monitorização não invasiva da rejeição em pacientes transplantados usando um marcapasso de dupla câmara e eletrodos endocavitários revestidos com estrutura fractal. Os sinais têm sido avaliados usando o sistema CHARM (Computerized Heart Acute Rejection Monitoring _ sistema computadorizado para monitorização da rejeição cardíaca aguda. Os relatórios obtidos com este sistema contêm curvas com parâmetros sensíveis à rejeição, que demonstram uma boa correlação com a clínica e os resultados das biópsias convencionais. A monitorização a longo prazo, usando estas análises, mostrou ser uma ferramenta valiosa no acompanhamento destes pacientes.

  9. Expresión transitoria del gen GUS en caña de azúcar usando Agrobacterium tumefaciens Transient gene expression in sugarcane using Agrobacterium tumefaciens

    Directory of Open Access Journals (Sweden)

    Martha Liliana Bonilla Betancourt

    2008-10-01

    Full Text Available En el estudio se desarrolló una metodología de transformación genética mediante Agrobacterium tumefaciens en cultivares colombianos de caña de azúcar. La transformación se evaluó mediante la expresión del gen GUS. Callos embriogénicos y explantes meristemáticos de los genotipos CC85-92, CC84-75 y CC87-505 se transformaron usando tres cepas (AGL-1, LBA4404 y EHA105 con el plásmido pCambia 1305.2 y dos (EHA105 y LBA4404 con pCambia 2301. Se usó el medio de infiltración (IM con acetosiringona y se evaluó el tiempo de cocultivo y la densidad óptica de la bacteria al momento de la inducción. Los genotipos mostraron respuesta diferencial con las combinaciones cepa-plásmido: obtuvieron mayor expresión del gen GUS cuando el genotipo CC85-92 se transformó con la cepa AGL-1-pCambia 1305.2. CC84-75 y CC87-505 mostraron mayor expresión cuando se transformaron con la cepa EHA105-pCambia 1305.2. Mayor eficiencia en la expresión se obtuvo cuando la bacteria se indujo en IM después de siete días de cocultivo y cuando la densidad óptica de la bacteria fue de 0.2(600nm al momento de la inducción. Se demostró superioridad de los explantes en la eficiencia de transformación.The aim of the present study was to develop a transformation method mediated by Agrobacterium in Colombian cultivars of sugarcane. Transformation was evaluated in each step through transient GUS expression. Embryogenic calli and meristematic explants of CC85-92, CC84-75 y CC87-505 cultivars, were transformed using Agrobacterium tumefaciens AGL-1, LBA 4404 and EHA 105 strains, harboring pCambia 1305.2 plasmid. Furthermore, strains LBA 4404 and EHA 105 harboring pCambia 2301 were also tested. Bacterian activator medium, named infiltration media (IM with acetosyringone was used. Co-cultivation time and bacteria optical density before induction were tested. Sugarcane cultivars evaluated showed differential response to different strain-plasmid combinations, obtaining

  10. Apropiación del concepto de función usando el software Geogebra

    OpenAIRE

    Martínez Gómez, José Nelson

    2013-01-01

    El trabajo presenta el diseño de una unidad didáctica que sirve de guía para la enseñanza y aprendizaje del concepto de función y de las características de funciones lineales y cuadráticas, que corresponden al currículo de grado noveno de Educación Básica. La unidad diseñada se convierte en una estrategia didáctica valiosa en el contexto local, regional y nacional que de forma interdisciplinaria e interactiva aborda la enseñanza de las temáticas mencionadas a través de tres módulos que siguen...

  11. Estudio del movimiento de caída libre usando vídeos de experimentos

    OpenAIRE

    Vera, Francisco; Rivera, Rodrigo; Fuentes, Raul; Romero Maltrana, Diego

    2015-01-01

    Los trabajos pioneros de Eadweard Muybridge en fotografía e imágenes en movimiento en el año 1878 que dieron origen al vídeo, así como los de Harold Edgerton en vídeos de alta velocidad realizado a mediados del siglo XX, buscaban entender el comportamiento de la naturaleza. Hoy en día el uso de vídeo continúa siendo una herramienta muy valiosa en todas las disciplinas científicas. En la actualidad, el uso de vídeo está siendo incorporado en innovadoras formas de enseñar física que...

  12. Detección de cavitación en una bomba centrífuga usando emisiones acústicas Cavitation detection in a centrifugal pump using acoustic emissions

    Directory of Open Access Journals (Sweden)

    Jabid Quiroga M.

    2012-12-01

    Full Text Available En el presente artículo se propone el uso de las emisiones acústicas para el monitoreo de la cavitación en una bomba centrífuga. Este monitoreo se ejecuta a través del seguimiento a unos indicadores de falla obtenidos a partir del valor RMS de la señal de emisiones acústicas en dominio tiempo y el valor RMS de los coeficientes de la Transformada Discreta Wavelet (TDW usando la onda madre db6 de la misma señal acústica. La experimentación se realiza en un banco dedicado que permite cavitar a una bomba de ½ hp en distintos niveles de severidad y bajo diferentes condiciones de bombeo. Resultados experimentales mostraron que los indicadores propuestos permiten detectar y evaluar cualitativamente los niveles de severidad de la cavitación en una bomba centrífuga.In this paper an acoustic emission based cavitation fault detection system is proposed for a centrifugal pump. The monitoring is performed tracking a fault indicator obtained using the RMS value of the acoustic emission signal in time domain and the RMS value of the coefficients obtained by applying discrete wavelet transform on the acoustic signal using db6 mother wavelet. Experiments in different cavitation levels and under different operation conditions are carried out in a ½ hp centrifugal pump dedicated test bed. Results showed that the proposed fault indicators are suitable for detecting and evaluating cavitation severities in a centrifugal pump.

  13. Nuevo enfoque para desarrollar sistemas de enseñanza-aprendizaje inteligentes usando mapas conceptuales y razonamiento basado en casos

    Directory of Open Access Journals (Sweden)

    Zenaida García Valdivia

    2011-10-01

    Full Text Available El uso de métodos pedagógicos con tecnologías de la información y las comunicaciones produce una cualidad nueva que favorece la tarea de generar, transmitir y compartir el conocimiento. Tal es el caso de la fortaleza pedagógica del empleo de los Mapas Conceptuales, que constituyen una herramienta para la gestión del conocimiento, por la posibilidad que estos ofrecen de personalizar el aprendizaje, compartir conocimiento, y para aprender a aprender. En este trabajo se expone un nuevo enfoque para elaborar Sistemas de Enseñanza-Aprendizaje Inteligentes, donde se combinan las técnicas de diagramas conceptuales e Inteligencia Artificial, usando el Razonamiento Basado en Casos como marco teórico para el modelado del alumno. El modelo propuesto se ha implementado en el sistema computacional HESEI, el cual ha sido aplicado exitosamente en la toma de decisiones en tareas de enseñanza-aprendizaje, por personas no expertas en el campo informático.

  14. Nueva tecnología constructiva usando materiales reciclados para casos de emergencia habitacional

    Directory of Open Access Journals (Sweden)

    Rosana Gaggino

    2003-01-01

    Full Text Available Se presenta una nueva alternativa tecnológica para cerramientos laterales para viviendas, desarrollada en el Centro Experimental de la Vivienda Económica - CEVE, el cual es un Centro de investigación dependiente del Consejo Nacional de Investigaciones Científicas y Tecnológicas de la República Argentina – CONICET. La tecnología propuesta permite el rápido montaje de una vivienda (una o dos jornadas en seco, es económica y de simple ejecución, por lo que es especialmente apta para dar una rápida solución a familias sin techo (personas de escasos recursos o víctimas de desastres naturales. Se trata sin embargo, de placas ejecutadas con materiales durables y de buena aislación térmica, por lo que además de solucionar una emergencia constituye una solución definitiva y confortable al problema habitacional. Estos materiales son residuos plásticos industriales reciclados, que reemplazan a los agregados pétreos de un hormigón común.

  15. Procesamiento paralelo en FPGA para convolución de imágenes usando Matlab

    Directory of Open Access Journals (Sweden)

    Diego Armando Giral Ramírez

    2015-01-01

    Full Text Available Este artículo describe el diseño de dos arquitecturas para un filtro de convolución de imágenes, que mediante Hardware co-simulation del toolbox de Matlab Xilinx SystemGenerator son implementadas en una FPGA Xilinx Spartan 3AN. El proyecto nace con el propósito de evaluar el rendimiento del procesamiento paralelo de imágenes con respecto al procesamiento en serie. Inicialmente se realiza el diseño y la implementación en hardware de las dos arquitecturas. Después, a partir de la medición de variables específicas, se selecciona la mejor arquitectura como alternativa de paralelización. Haciendo uso de las herramientas que brinda el toolbox, se evalúa la relación entre grado de paralelismo, tiempos de ejecución y recursos hardware utilizados. Finalmente, y entre las conclusiones más importantes, se obtiene que el tiempo de procesamiento de la imagen es reducido notablemente a medida que aumenta su grado de paralelización.

  16. Control de brazo electrónico usando señales electromiográficas

    Directory of Open Access Journals (Sweden)

    Jorge Andrés García-Pinzón

    2015-05-01

    Full Text Available Los trabajos enfocados en la extracción de patrones en señales electromiográficas (SEMG han venido creciendo debido a sus múltiples aplicaciones. En este artículo se presenta una aplicación en la cual se implementa un sistema electrónico para el registro de las SEMG de la extremidad superior en un sujeto, con el fin de controlar de forma remota un brazo electrónico. Se realizó una etapa de preprocesamiento de las señales registradas, para eliminar información poco relevante, y reconocimiento de zonas de interés; enseguida se extraen los patrones y se clasifican. Las técnicas utilizadas fueron: análisis wavelet (AW, análisis de componentes principales (ACP, transformada de fourier (TF, transformada del coseno discreta (TDC, energía, máquinas de soporte vectorial (MSV o SVM y redes neuronales (RNA. En este artículo se demuestra que la metodología planteada permite realizar un proceso de clasificación con un rendimiento superior al 95%. Se registraron más de 4000 señales.

  17. AL Amyloidosis

    Directory of Open Access Journals (Sweden)

    Desport Estelle

    2012-08-01

    Full Text Available Abstract Definition of the disease AL amyloidosis results from extra-cellular deposition of fibril-forming monoclonal immunoglobulin (Ig light chains (LC (most commonly of lambda isotype usually secreted by a small plasma cell clone. Most patients have evidence of isolated monoclonal gammopathy or smoldering myeloma, and the occurrence of AL amyloidosis in patients with symptomatic multiple myeloma or other B-cell lymphoproliferative disorders is unusual. The key event in the development of AL amyloidosis is the change in the secondary or tertiary structure of an abnormal monoclonal LC, which results in instable conformation. This conformational change is responsible for abnormal folding of the LC, rich in β leaves, which assemble into monomers that stack together to form amyloid fibrils. Epidemiology AL amyloidosis is the most common type of systemic amyloidois in developed countries with an estimated incidence of 9 cases/million inhabitant/year. The average age of diagnosed patients is 65 years and less than 10% of patients are under 50. Clinical description The clinical presentation is protean, because of the wide number of tissues or organs that may be affected. The most common presenting symptoms are asthenia and dyspnoea, which are poorly specific and may account for delayed diagnosis. Renal manifestations are the most frequent, affecting two thirds of patients at presentation. They are characterized by heavy proteinuria, with nephrotic syndrome and impaired renal function in half of the patients. Heart involvement, which is present at diagnosis in more than 50% of patients, leading to restrictive cardiopathy, is the most serious complication and engages prognosis. Diagnostic methods The diagnosis relies on pathological examination of an involved site showing Congo red-positive amyloid deposits, with typical apple-green birefringence under polarized light, that stain positive with an anti-LC antibody by immunohistochemistry and

  18. Estudio de la grasa de teobroma ozonizada usando la Resonancia Magnética

    Directory of Open Access Journals (Sweden)

    Fernández Torres, Irán

    2007-03-01

    Full Text Available Ozonation of theobroma fat at different applied ozone dosages was carried out and peroxide indexes along with antimicrobial activity were determined. The reaction products were identified using Proton Nuclear Magnetic Resonance Spectroscopy (1H NMR. The principal signal intensity values were used for following the reaction course between ozone and theobroma fat. The reaction was followed up to peroxide index values of 544 mmol-equiv/kg. The intensities of olefinic proton signals decreased with the gradual increase in ozone concentration until disappearing completely. The Criegee ozonides obtained at 87.4 mg/g of ozone doses were approximately 3.7 times higher than at the beginning of the reaction. The highest action spectrum of antimicrobial activity was obtained with the higher peroxide index. These results suggest that the 1H NMR spectroscopic technique provides valuable information about of the ozonization grade of theobroma fat which produces an affective antimicrobial activity against Candida albicansSe realizó un estudio de la ozonización de la grasa de teobroma el cual fue seguido a diferentes dosis de ozono y fueron determinados los índices de peróxidos y su actividad antimicrobiana. Los productos de reacción fueron identificado por la espectroscopia de Resonancia Magnética Nuclear Protónica (RMN 1H. Los principales valores de intensidad de las señales fueron usados para el seguimiento de la reacción entre el ozono y la grasa de teobroma. La reacción fue seguida hasta un valor de índice de peróxidos de 1 544 mmolequiv/kg. Las intensidades de las señales de los protones olefínicos desaparecen con un gradual incremento de la concentración de ozono. Los ozónidos de Criegee obtenidos a dosis de ozono de 87,4 mg/g fueron 3,7 veces mayores que los obtenidos al inicio de la reacción. El mayor espectro de acción de la actividad antimicrobiana fue obtenido a mayor índice de peróxidos. Estos resultados sugieren que la t

  19. EXTENSIÓN DE UN DATA WAREHOUSE USANDO ETIQUETAS LINGÜÍSTICAS Y OPERADOR CUBE

    Directory of Open Access Journals (Sweden)

    Angélica Urrutia Sepúlveda

    2007-12-01

    Full Text Available RESUMEN La motivación de este trabajo, es poder extender un Almacén de datos o Datawarehouse que entrega información cuantitativa a información cualitativa, lo que permite darle un significado lingüístico a la información numérica que requiere la gestión de la información en la toma de decisiones. Para extender el Datawarehouse, se utiliza la lógica difusa, teoría matemática que permite la especificación de requerimientos graduales o flexibles. Esto flexibiliza la representación y manipulación de información de los datos en una Base de Datos, donde los requerimientos de los usuarios son de una naturaleza de la aplicación de datos imprecisos. La solución que se propone, es desarrollar un conjunto de pasos que denominamos MFDW y parten desde la base de datos fuentes hasta la implementación de cubos extendidos con etiquetas lingüísticas (FuzzyMedida. Para realizar esta extensión, se crea M-FIRST que es una extensión del FSQL [5] para base de datos relacional difusas, y se anexa a un diseño estrella o copo de nieve de modelos multidimensionales para un determinado almacén de datos. Aquí se toma una medida en particular del Datawarehouse, se le agregan etiquetas lingüísticas requeridas por el usuario, las cuales varían de acuerdo al cruce de dimensiones que se realicen sobre esa medida. Finalmente se construye una herramienta Front-End (Web, que permite almacenar y consultar información imprecisa. ABSTRACT The purpose of this investigation is to extend the generally accepted concept of datawarehousing that blends ordinal quantitative and qualitative information, to include class descriptors that describe a spectrum of values for sets of domain dependent data. It is proposed that this kind of `fuzzy`data, when combined with the ordinal data, will enrich the information provided to managers by making it more meaningful. Fuzzy logic is used to define this broad spectrum data because it enables formal requirement

  20. Determinación del comportamiento de la protección de los recubrimientos en los espejos, usando la técnica de Espectroscopía de Impedancia Electroquímica

    Directory of Open Access Journals (Sweden)

    Bolaños-Rodríguez, E.

    2003-06-01

    Full Text Available In this paper we have determined the behaviour of the protection of the coating of mirrors, using the technique of Electrochemical Impedance Spectroscopy. The system is evaluated with the sodium chloride electrolyte (3 % weight for 0, 5, 24 h and 15 d having the electrolyte introduced in the measuring cell. The paint system used in the protection of mirrors behaves very much like the classical models proposed for the corrosion that a given coating system undergoes in an aggressive medium, according to the results obtained in Electrochemical Impedance Spectroscopy tests for different contact times contact of the system with the sodium chloride electrolyte at weight of 3 %.

    En este trabajo se determina el comportamiento de la protección de los recubrimientos en los espejos, usando la técnica de Espectroscopía de Impedancia Electroquímica. Se evalúa el sistema en presencia del electrolito cloruro de sodio (3 % peso a las O, 5, 24 h y 15 d de introducir el electrolito a la celda de medición. El sistema de pintura utilizado en la protección de los espejos se comporta de forma similar a los modelos clásicos propuestos para el deterioro que sufre un sistema de recubrimientos orgánicos en un medio agresivo, de acuerdo a los resultados obtenidos en los ensayos de Espectroscopía de Impedancia Electroquímica para los diferentes tiempos en contacto del sistema con el electrolito cloruro de sodio al 3 % peso.

  1. MODELADO DEL PRECIO SPOT DE LA ELECTRICIDAD EN BRASIL USANDO UNA RED NEURONAL AUTORREGRESIVA ELECTRICITY SPOT PRICE MODELLING IN BRASIL USING AN AUTOREGRESSIVE NEURAL NETWORK

    OpenAIRE

    Juan D. Velásquez; Isaac Dyner; Reinaldo C. Souza

    2008-01-01

    Una red neuronal autorregresiva es estimada para el precio mensual brasileño de corto plazo de la electricidad, la cual describe mejor la dinámica de los precios que un modelo lineal autorregresivo y que un perceptrón multicapa clásico que usan las mismas entradas y neuronas en la capa oculta. El modelo propuesto es especificado usando un procedimiento estadístico basado en el contraste del radio de verosimilitud. El modelo pasa una batería de pruebas de diagnóstico. El procedimiento de espec...

  2. FACTORES AMBIENTALES QUE AFECTAN LA EDAD AL PRIMER PARTO Y PRIMER INTERVALO DE PARTOS EN VACAS DEL SISTEMA DOBLE PROPOSITO

    OpenAIRE

    Caty Martínez B; Luz Botero A; Oscar Vergara G

    2009-01-01

    Objetivo. Determinar los factores que influyen en la edad al primer parto (AFC) y primer intervalo de parto (PIDP) en hembras bovinas bajo el sistema de doble propósito, en la finca “El Rodeo”, municipio de Magangué, Bolívar - Colombia. Materiales y métodos. Se analizaron 379 datos provenientes de los registros productivos entre los años 1993 hasta 2002, usando el programa estadístico GLM del Statistical Analysis System, donde se obtuvieron la media y el error estándar de cada fuente de vari...

  3. Correlação de longo alcance em sistemas binários de raios-x usando remoção de flutuações

    Science.gov (United States)

    Pereira, M. G.; Moret, M. A.; Zebende, G. F.; Nogueira, E., Jr.

    2003-08-01

    Neste trabalho é proposta uma metodologia de analise de series temporais de fontes astrofísicas, baseada no método proposto por Peng et al. (1994) e Liu et al. (1999), o qual consiste na idéia de que uma série temporal correlacionada pode ser mapeada por um processo de busca de auto-similaridades em diversas escalas de tempo n. Removendo as eventuais tendências e integrando o sinal observado, é obtida uma medida do desvio médio quadrático das flutuações do sinal integrado F(n)~na, onde a representa o fator de escala associado com a auto-similaridade da correlação de longo alcance do sinal. Baseado nos valores obtidos de a, é possível distinguir entre os casos de sinais não-correlacionados, tipo ruído branco (a = 0,5), sinal anti-persistentes (a 0,5). Usando esta metodologia, foram analisadas 129 curvas de luz de sistemas binários de raios-X, provenientes do banco de dados públicos de observações feitas pelo instrumento All Sky Monitor, a bordo do satélite Rossi X-Ray Timing Explorer (ASM-RXTE). Foram identificadas a presença de a'0,5 em mais de 90% dos sistemas estudados, implicando em dizer que as flutuações de intensidade observadas apresentam correlação de auto-similaridade, sem entretanto, indícios de apresentarem uma escala de tempo característica das flutuações de intensidade. Sistemas onde são observadas erupções (flares), apresentam sistematicamente a > 0,5, característica esta, possivelmente associada com persistência das flutuações de densidade de disco ou taxa de acréscimo de massa. Os sistemas com curvas de luz onde nao são observadas as erupções apresentam uma distribuição normal centrada em a~0,62+/-0,10. Referências ¾ Peng, C.-K., Buldyrev, S.V., Havlin, S., Simons, M., Stanley, H.E., e Goldberg, A.L., Phys. Rev. E, (49), 1685 (1994). ¾ Liu, Y., Gopikrishnan, P., Cizeau, P., Meyer, M., Peng,C.-K., e Stanley, H.E., Phys. Rev. E, (60), 1390 (1999).

  4. MODELADO DEL PRECIO DEL CAFÉ COLOMBIANO EN LA BOLSA DE NUEVA YORK USANDO REDES NEURONALES ARTIFICIALES MODELLING OF THE COLOMBIAN COFFEE PRICE IN THE NEW YORK STOCK EXCHANGE USING ARTIFICIAL NEURAL NETWORKS

    OpenAIRE

    Juan David Velásquez Henao; Mario Alberto Aldana Dumar

    2007-01-01

    En este artículo, se modela el precio promedio mensual del café colombiano en la Bolsa de Nueva York, usando varios modelos alternativos. El modelo final seleccionado está compuesto por una componente lineal autorregresiva más una red neuronal artificial tipo perceptron multicapa con dos neuronas en la capa oculta, que permite representar la dinámica que sigue el valor esperado de la serie de precios; mientras que la dinámica de los residuales es especificada usando un proceso heterocedástico...

  5. Evaluation of the Water Requirements for a Greenhouse Tomato Crop using the Priestley-Taylor Method Evaluación del Consumo de Agua de un Cultivo de Tomate en Invernadero Usando el Método de Priestley-Taylor

    Directory of Open Access Journals (Sweden)

    Héctor Valdés-Gómez

    2009-03-01

    ógica automática (AWS fue instalada dentro del invernadero para medir radiación solar (Rgi, radiación neta (Rn, temperatura del aire (Ta y humedad relativa (RH. Una segunda AWS fue establecida sobre una cubierta herbácea para medir las condiciones atmosféricas al exterior del invernadero. El experimento se condujo en la Estación Experimental Panguilemo (35°23’ S, 71°40’ O, 110 m.s.n.m. durante los meses de agosto a diciembre del 2000. Las estimaciones de ETreal obtenidas por el modelo PT fueron comparadas con los valores calculados por el método del balance hídrico (WB. En este estudio los valores de ETreal obtenidos por PT fueron calculados usando: a Rgi y flujo de calor del suelo (G = 0; b Rgi y G ≠ 0; c radiación solar medida al exterior del invernadero (Rge y G = 0; y d Rge y G ≠ 0. Para estos casos los resultados indicaron que el modelo de PT fue capaz de estimar del tomate con errores menores que un 5%. Asimismo, la Rn fue calculada con un error absoluto relativo y una desviación media de no más del 6% y 0,07 mm d-1, respectivamente, ya sea utilizando Rgi o Rge. La utilización de un valor igual a cero para valores diarios de flujo de calor del suelo no afectó el cálculo de los valores de ETreal. Así, el modelo de PT evaluado en esta investigación podría ser usado para programar el riego de un cultivo de tomates bajo invernadero usando mediciones internas de temperatura y humedad relativa, y mediciones externas de radiación solar. En este caso, el modelo de PT predijo la ETreal con un error de un 6,1%.

  6. Vulnerabilidades usando SDR

    OpenAIRE

    Ledesma Peña, Carlos

    2014-01-01

    Un sistema de SDR (Software Defined Radio) es un sistema de radio programable que delega gran parte del procesamiento hecho clásicamente en hardware,en software corriendo en un ordenador. Dos ventajas inmediatas de un dispositivo de SDR frente a un dispositivo de radio tradicional son el abaratamiento del coste del hardware (menos y menos complejo) y la facilidad de modificación de la funcionalidad específica de la radio (implementaciones software, tan simple como programar cualquier proto...

  7. Optimización del tratamiento de aguas residuales de cultivos de flores usando humedales construidos de flujo subsuperficial horizontal

    Directory of Open Access Journals (Sweden)

    Mónica L. Jaramillo-Gallego

    2016-02-01

    Full Text Available Resumen Objetivo: optimizar un sistema de tratamiento de aguas residuales de cultivos de flores, con el fin de mejorar la eficiencia en la remoción de los contaminantes, usando humedales construidos de flujo subsuperficial-horizontal. Metodología: se realizó un estudio de tipo exploratorio experimental en dos etapas, en la primera se efectuó el acondicionamiento fisicoquímico y biológico del sistema de tratamiento, en la segunda, se llevó a cabo el seguimiento de la remoción de los contaminantes durante nueve meses, para lo cual se monitoreó la demanda química de oxígeno, demanda biológica de oxígeno, sólidos totales, sólidos suspendidos totales, pH y oxígeno disuelto. Resultados: Se logró mejorar la eficiencia del sistema de tratamiento en 7,1% para la Demanda biológica de oxígeno, 4,1% Demanda química de oxígeno, 56,9% sólidos totales y 117,2% solidos suspendidos totales. Conclusión: La concentración de DQO disminuyó con el tratamiento primario (Precipitación y oxidación química y favoreció la eficiencia del sistema de tratamiento secundario, dado que las aguas a tratar tenían valores muy altos de DQO que pueden saturar los humedales con contaminantes persistentes. Se podrían obtener mayores eficiencias, si se logra mejorar el sistema de tratamiento primario. Abstract Objective: to optimize the wastewater treatment system of flower crops in order to improve pollutant removal efficiency, using a horizontal subsurface flow constructed wetland. Methodology: An exploratory experimental study was conducted in two stages; in the first stage the treatment system was conditioned physically, chemically and biologically. In the second stage pollutant removal was monitored for nine months. To achieve this, chemical oxygen demand, biological oxygen demand, total solids, total suspended solids, pH and dissolved oxygen were monitored. Results: It was possible to improve the efficiency of the treatment system in 7.1% for

  8. Materiales de Al2O3 - MgAl2O4 - CaAl12O19 - Ca2Mg2Al28O46 obtenidos mediante un proceso de sinterización reactiva entre Al2O3 y CaMg(CO32

    Directory of Open Access Journals (Sweden)

    Pena, P.

    2002-08-01

    Full Text Available Taking into account the system Al2O3-MgO-CaO, refractory materials containing Al2O3-MgAl2O4-CaAl12O19-Ca2Mg2Al28O46 has been obtained by reaction-sintering of appropriate mixtures of Al2O3 and CaMg(CO32. The study of the mechanism of reaction was carried out by differential thermal analysis (DTA and thermogravimetry (TG, followed by dilatometric and xray diffraction (XRD studies. A static study of the reaction was performed at different temperatures. After each thermal treatment a XRD analysis of the phases present was made, as well as a microestructural study by scanning electron microscopy (SEM coupled with energy-dispersive spectroscopy (EDS. From the results obtained, and taking into account the free energy of formation of the different compounds, the mechanism of reaction was established.Utilizado la información suministrada por el diagrama de equilibrio de fases Al2O3-MgO-CaO se ha diseñado y obtenido un material de Al2O3-MgAl2O4-CaAl12O19-Ca2Mg2Al28O46 mediante sinterización reactiva de una mezcla de Al2O3 y CaMg(CO32. Las reacciones que tienen lugar en la mezcla durante el proceso se han estudiado usando técnicas de análisis térmico diferencial, termogravimetrico y dilatometría. Muestras reaccionadas a temperaturas seleccionadas se han estudiado por difracción de rayos X y microscopía electrónica de barrido con microanálisis mediante dispersión de energías. Los resultados obtenidos revelan que la reacción entre las materias primas tiene lugar en varias etapas con formación de fases transitorias, dando lugar a una microestructura final con granos aciculares de CaAl12O19 y partículas de la fase ternaria Ca2Mg2Al28O46 formadas en aquellos puntos en los que entran en contacto las fases de MgAl2O4 y CaAl12O19.

  9. Evaluación comparativa del desempeño de los sistemas estatales de salud usando cobertura efectiva Benchmarking of performance of Mexican states with effective coverage

    Directory of Open Access Journals (Sweden)

    Rafael Lozano

    2007-01-01

    Full Text Available Realizar un análisis comparativo del desempeño (benchmarking de las unidades subnacionales en un sistema de salud descentralizado es importante para favorecer la rendición de cuentas, monitorear el progreso, identificar los factores que determinan tanto el éxito como el fracaso, y crear una cultura basada en la evidencia. Desde 2001, la Secretaría de Salud de México se ha dedicado a desarrollar esta tarea basándose en el concepto de cobertura efectiva promovido por la Organización Mundial de la Salud (OMS, que la define como la fracción de ganancia potencial en salud que el sistema de salud podría aportar, con los servicios que actualmente ofrece. Usando los sistemas de información en salud, que incluyen encuestas de salud representativas a nivel estado, registros vitales y registros de egresos hospitalarios, se ha monitoreado la prestación de 14 intervenciones para mejorar la salud entre 2005 y 2006. La cobertura efectiva en general va desde 54% en Chiapas hasta 65% en el Distrito Federal. La cobertura efectiva para intervenciones en salud materno-infantil es mayor que para las intervenciones que abordan otros problemas de salud del adulto. La cobertura efectiva para el quintil de ingresos más bajo es de 52%, comparada con 61% para el quintil de ingresos más alto. La cobertura efectiva guarda especial relación con el gasto público en salud per cápita en todos los estados, y esta relación es más estrecha con las intervenciones ajenas a la salud materno-infantil que con las que tienen que ver directamente con ella. También se observan variaciones considerables en la cobertura efectiva en niveles de gasto similares. Asimismo, se discuten algunas implicaciones para el desarrollo que debiera seguir el sistema de información en salud en México. Este enfoque alienta a quienes toman decisiones a concentrarse en brindar servicios de calidad y no sólo en ofrecer la disponibilidad del servicio. El cálculo de la cobertura efectiva

  10. Predicción de los precios de contratos de electricidad usando una red neuronal con arquitectura dinámica

    Directory of Open Access Journals (Sweden)

    Juan David Velásquez Henao

    2010-04-01

    Full Text Available Los contratos en los mercados liberalizados de electricidad constituyen una herramienta para proteger a los agentes de la volatilidad; en este contexto, los pronósticos de los precios son una entrada clave para la toma de decisiones estratégicas y operativas de los agentes. En este artículo, se pronostican los precios promedios de los contratos despachados en el mercado eléctrico colombiano, usando una red neuronal con arquitectura dinámica conocida como DAN2. El modelo desarrollado es capaz de capturar la dinámica intrínseca de la serie de precios y de pronosticar el precio para el siguiente mes con más precisión que la metodología ARIMA clásica, para horizontes de predicción de 12 y 24 meses

  11. OTIMIZAÇÃO USANDO ALGORITMO GENÉTICO DE UM MODELO DE PROPAGÇÃO BASEADO EM EQUAÇÕES PARABÓLICAS

    Directory of Open Access Journals (Sweden)

    Antonio Carlos Vilanova

    2013-01-01

    Full Text Available Este artigo apresenta uma avaliação metodológica para otimizar parâmetros em um conhecido modelo de propagação de ondas de rádio na troposfera. O modelo de propagação é baseado no Divisor de passos de Fourier para resolver equações parabólicas. Nossa abordagem utiliza algoritmo genético para determinar os valores dos parâmetros que maximize a intensidade de campo em uma determinada posição do observador. Usando algoritmo genético o tempo necessário na busca dos parâmetros ótimos é reduzido significativamente. A avaliação preliminar dos resultados através da simulação mostra que a nossa abordagem é promissora.

  12. Expresión transitoria del gen GUS en caña de azúcar usando Agrobacterium tumefaciens Transient gene expression in sugarcane using Agrobacterium tumefaciens

    OpenAIRE

    Martha Liliana Bonilla Betancourt; Jaime Eduardo Muñoz Flórez; Fernando ángel Sánchez

    2008-01-01

    En el estudio se desarrolló una metodología de transformación genética mediante Agrobacterium tumefaciens en cultivares colombianos de caña de azúcar. La transformación se evaluó mediante la expresión del gen GUS. Callos embriogénicos y explantes meristemáticos de los genotipos CC85-92, CC84-75 y CC87-505 se transformaron usando tres cepas (AGL-1, LBA4404 y EHA105) con el plásmido pCambia 1305.2 y dos (EHA105 y LBA4404) con pCambia 2301. Se usó el medio de infiltración (IM) con acetosiringona...

  13. Predicción no lineal de caudales medios mensuales usando funciones de influencia radial y técnicas espectrales.

    OpenAIRE

    Rojo Hernández, Julián David; Carvajal Serna, Luis Fernando

    2012-01-01

    La estrecha relación no lineal entre los caudales y los procesos climáticos de escala global justifican la modelación no lineal para la predicción de caudales. El presente trabajo muestra una aproximación a la dinámica no lineal de los caudales usando un modelo no paramétrico de regresión basado en las funciones de influencia radial y técnicas de descomposición espectral. El modelo propuesto es aplicado para la predicción de los caudales medios mensuales para horizontes de pronóstico de 1,3 y...

  14. Calculo y comparacion de la prima de un reaseguro de salud usando el modelo de opciones de Black-Scholes y el modelo actuarial

    Directory of Open Access Journals (Sweden)

    Luis Eduardo Giron

    2015-12-01

    Full Text Available La presente investigación pretende calcular y comparar la prima de un reaseguro  usando el modelo de opciones de Black-Scholes y el modelo clásico actuarial tradicional. El período de análisis va desde enero de 2011 hasta diciembre de 2012. Los resultados obtenidos muestran que el modelo de Black-Scholes, que se utiliza normalmente para valorar opciones financieras, puede ser también usado para la estimación de primas de reaseguros de salud; y que la prima neta estimada a partir de este modelo se aproxima a las establecidas por el método actuarial, excepto cuando el deducible del reaseguro es muy alto (por encima de $200.000.000.

  15. Extração do óleo de manjericão usando fluido supercrítico: analise experimental e matemática

    Directory of Open Access Journals (Sweden)

    Nídia Alves de Barros

    2014-01-01

    Full Text Available O óleo essencial de manjericão (Ocimum basilicum L. é valorizado no mercado internacional e amplamente usado nas indústrias de condimentos, cosméticos e medicinais. Entre todos os processos que podem ser aplicados na obtenção do óleo, a extração usando fluido supercrítico (EFS pode ser um método seletivo e eficiente, dependendo das condições operacionais, como temperatura e pressão, que precisam ser otimizadas. O objetivo deste estudo foi comparar a eficiência da extração supercrítica, utilizando planejamento experimental, na extração do óleo de manjericão com os métodos convencionais (hidrodestilação e soxhlet. Para a realização da parte experimental, foi utilizado dióxido de carbono como solvente para a EFS e hexano, para aplicação no soxhlet. Foi realizado um delineamento central composto rotacional (DCCR, aplicando três pressões (100, 200 e 300 bar e três temperaturas (30, 40 e 50ºC. Através da hidrodestilação, obteve-se o menor rendimento (0,26%, usando o Soxhlet, o rendimento foi de 2,39% sendo superior, comparado á EFS, que foi de 0,43%. O DCCR mostrou que, para otimizar o processo, é necessário aumentar a pressão e a temperatura para o alcance de maiores rendimentos. Foi possível constatar que o modelo matemático representou bem o processo de extração, propiciando o "scale-up" deste.

  16. All About ALS

    Science.gov (United States)

    ... please review our exit disclaimer . Subscribe All About ALS Understanding a Devastating Disorder In the summer of ... of research dollars—for a fatal disease called ALS. ALS stands for amyotrophic lateral sclerosis. It’s also ...

  17. Retention of chromium by modified Al-Bentonite Retenção de cromo por Al-bentonita modificada

    Directory of Open Access Journals (Sweden)

    C. Volzone

    2002-09-01

    Full Text Available Retention of chromium (III from a tanning wastewater by modified Al-bentonites was studied. One bentonite from San Juan province, Argentina, was used. Al-bentonite was prepared by contact of bentonite with hydrolyzed OH-Al solutions (0.10 M in Al for 24 hours. The modified Al-bentonites were obtained by: a treatment with 0.5 M sodium chloride; b with 0.5 M sodium chloride adjusted at pH 8; and c treatment with an hexametaphosphate solution after sodium addition. Then, the samples were dried at 100 °C and heated at 500 °C. The chromium (III retention by samples was carried out in batch system putting in contact the material with a 2000 ppm Cr tannery waste at different times. The retained chromium was characterized by analyzing the supernatant using UV-visible spectroscopy. The different chromium retention was correlated with structural characteristics of the solids.Foi estudada a retenção de cromo (III de águas residuais por meio de Al-bentonitas modificadas. Foi usada uma bentonita da província de San Juan, Argentina. As bentonitas-Al forma preparadas colocando-as em contato com soluções (0,10 M Al hydrolizadas de OH-Al durante 24 horas. As bentonitas-Al modidicadas foram obtidas por meio de: a tratamento com cloreto de sódio 0,5 M; b com cloreto de sódio 0,5 M sodium com pH ajustado para 8; e c tratamento com uma solução de hexametafosfato após a adição de sódio. As amostras foram então secas a 100 °C e aquecidas a 500 °C. A retenção do cromo (III pelas amostras foi feita em lotes colocando o material em contato em diferentes tempos com um resíduo contendo 2000 ppm de cromo. O cromo retido foi caracterizado por meio de análise do sobrenadante usando espectroscopia UV-visível. As diferentes retenções de cromo foram correlacionadas com características estruturais dos sólidos.

  18. Estudio preliminar del uso de un protocolo para evaluar el bienestar de vacas lecheras usando observaciones basadas en el animal Preliminary study of the use of a protocol to assess the welfare of dairy cattle using animal-based observations

    Directory of Open Access Journals (Sweden)

    C Arraño

    2007-01-01

    Full Text Available El objetivo del presente estudio fue evaluar el bienestar de vacas de lechería usando un protocolo simplificado de observaciones basadas en el animal. Las 22 lecherías se visitaron por una sola vez entre marzo y junio del 2005. Las lecherías fueron seleccionadas por conveniencia, tomando en cuenta la disposición del propietario para participar, su facilidad de acceso y el tamaño del rebaño (291 ± 71,6. De las 22 lecherías, 5 de ellas mantenían a sus vacas a pradera; de las 17 restantes, 4 tenían estabulación permanente y 13 las mantenían estabuladas durante la noche. La visita comenzó dos horas antes de la ordeña de la tarde; durante la visita los animales fueron observados sistemáticamente al momento de la ordeña, para evaluar la condición física y el comportamiento. Las observaciones recopiladas fueron ingresadas a una planilla electrónica Microsoft® Excel XP. Los resultados encontrados para las indicadores de bienestar basados en observaciones de los animales se agruparon en cinco categorías (A: lo mejor/ E: lo peor, luego las granjas fueron ordenadas de acuerdo al porcentaje de indicadores en cada categoría. Las 22 lecherías tuvieron al menos un indicador en la categoría A. Una sola lechería logró tener cinco indicadores de los siete observados, en la categoría A. El indicador mejor evaluado fue la condición corporal, y el peor evaluado fue la "zona de fuga" de las vacas. Se concluye que ninguna lechería tuvo resultados consistentemente buenos o malos en relación a las demás, al evaluar el bienestar de las vacas mediante observaciones basadas en el animalThe aim of this study was to evaluate the welfare of dairy cows using a simplified protocol of animal-based observations. Twenty-two commercial dairy farms in the province of Valdivia, Chile, were visited once between March and July 2005. The farms were selected considering the willingness of the owners to participate, distance from the university and size of

  19. Pollution trends using bark of morus alba in the cities of buenos aires and mendoza (Argentina Tendências de poluição usando cascas de morus alba nas cidades de buenos aires e mendoza (Argentina

    Directory of Open Access Journals (Sweden)

    Patricia Perelman

    2010-06-01

    mostraram que Al, Fe, Mg e a acumulação de outros elementos indicaram que as partículas do solo foram espalhadas pelo vento. Na área metropolitana de Buenos Aires, o Ba e o Zn apresentaram as mais altas concentrações, possivelmente por causa do intenso tráfego automotor. O trabalho atual é uma contribuição preliminar, usando-se as árvores de Morus alba como um método indireto para estimar as tendências da poluição.

  20. Energy saving using solar filters with iron base in windows; Ahorro de energia usando filtros solares con base en hierro en ventanas

    Energy Technology Data Exchange (ETDEWEB)

    Chavez Galan, Jesus

    2003-07-01

    termico generado al interior de las edificaciones por las inadecuadas propiedades de los materiales de construccion, se desarrollaron en este trabajo filtros solares con base en hierro por medio de los cuales se logra un control selectivo de la radiacion solar que se transmite a traves de las ventanas. Estos filtros solares consisten en peliculas delgadas de FeO depositadas sobre sustratos de vidrio cal-sosa (el mas usado en nuestro pais para las edificaciones) de 600x300x3 mm, por medio de la tecnica de sputtering asistida con radiofrecuencia y magnetrones planos, partiendo de un blanco de hierro puro de 127x254 mm y usando un plasma de argon. Para obtener el grado de oxidacion deseado en el hierro, pequenas muestras (45 x 22 mm) fueron sometidas a un proceso de calentamiento en una atmosfera reductora constituida de 50% H{sub 2} + 50% N{sub 2}, durante un periodo de tiempo de 10 minutos a una temperatura de 400 C. Los filtros solares con base en FeO presentan una transmisividad de 30.2% para el intervalo visible del espectro electromagnetico (radiacion con longitud de onda de 380-780 nm), y de 39.9% para el infrarrojo cercano (radiacion con longitud de onda de 780-2500 nm); mientras que su reflectividad es de 17.5 y 19%, para los intervalos visibles e infrarrojo cercano del espectro electromagnetico respectivamente. Se realizo una simulacion, a traves del software Energy 10, del comportamiento energetico de una casa-habitacion cuando utilizan en las ventanas vidrios simples (una lamina) tipo cal-sosa, asi como tambien cuando esta misma edificacion usa en las ventanas los filtros solares con base en FeO desarrollados. Ambos casos se comparan obteniendose asi los posibles ahorros de energia por el uso de dichos filtros solares en las ventanas. Las simulaciones fueron llevadas a cabo para diferentes localidades del pais, obteniendose que los filtros solares con base en FeO desarrollados, permiten ahorros de energia principalmente por concepto de acondicionamiento de aire

  1. Cómo mejorar la ensañanza del inglés usando la pizarra digital interactiva

    OpenAIRE

    Lampérez Zubía, María

    2013-01-01

    Las Tecnologías de la Información y de la Comunicación (TIC) están teniendo una gran influencia en nuestra vida cotidiana y, como consecuencia de su uso generalizado, la escuela, al igual que la sociedad, va cambiando. En este trabajo queremos abordar varias cuestiones sobre el uso de las TICs, y más en concreto, sobre una de las herramientas más utilizadas, la Pizarra Digital Interactiva (PDI), en la enseñanza del inglés en primaria. En primer lugar, se explicará detenidamente la relación qu...

  2. Caracterización y desempeño del recubrimiento μ-altin durante el fresado del ti-6al-4v

    OpenAIRE

    Moreno Téllez, Carlos Mauricio; Sánchez, José Manuel; Higuera Cobos, Oscar Fabián

    2012-01-01

    Las propiedades mecánicas y el desempeño del recubrimiento μ-AlTiN depositado por la técnica PVD por arco catódico ha sido investigada para una composición específica de Al0,67Ti0,33N depositada en sustrato de WC-Co y acero AISI D2; su estructura fue analizada usando SEM, EDAX, DRX, AFM y TEM, y las propiedades mecánicas se analizaron a partir de medidas de nanoindenta-ción. El desempeño del recubrimiento fue evaluado durante el fresado de una aleación de titanio (Ti6Al4V). Una película de Ti...

  3. Membranas poliméricas de PE-g-MA-Al/AlPO4 impregnado com Fe, Al - utilização na recuperação de efluentes de galvanoplastia

    Directory of Open Access Journals (Sweden)

    Joice Andrade de Araújo

    2014-01-01

    Full Text Available Neste trabalho foram desenvolvidas membranas filtrantes de materiais híbridos de polietileno de alta densidade modificado com anidrido maleico e ionizado com hidróxido de alumínio (PE-g-MA-Al (matriz orgânica e fosfato de alumínio amorfo puro (AlPO4 ou impregnado com ferro e/ou alumínio (fase dispersa inorgânica. Essas membranas foram obtidas nas composições de PE-g-MA-Al (M1, PE-g-MA-Al/AlPO4 (M2, PE-g-MA-Al/AlPO4-Al (M3, PE-g-MA-Al/AlPO4-Fe (M4 e PE-g-MA-Al/AlPO4-Fe,Al (M5, na proporção de 97/3% em massa, pelo método de "casting", usando xileno à quente e sob refluxo, como solvente. As técnicas de espectroscopia na região do infravermelho (FTIR, difração de raios X (DRX, análise termogravimétrica (TGA, análise textural, tensão superficial e microscopia eletrônica de varredura (MEV serviram para comprovar a influência da natureza dos materiais e da metodologia usada na confecção das membranas na incorporação da fase inorgânica na matriz polimérica e nas propriedades dos materiais híbridos resultantes. A aplicação das membranas na recuperação de metais presentes no efluente de galvanoplastia mostrou que a presença do ferro e/ou alumínio influenciou na morfologia e nas propriedades texturais desses materiais, e consequentemente na utilização como membranas mesoporosas de ultrafiltração, com os melhores resultados apresentados por M1 e M3 na recuperação de ferro (32 e 35% e zinco (62 e 60%.

  4. MODELADO DEL PRECIO SPOT DE LA ELECTRICIDAD EN BRASIL USANDO UNA RED NEURONAL AUTORREGRESIVA ELECTRICITY SPOT PRICE MODELLING IN BRASIL USING AN AUTOREGRESSIVE NEURAL NETWORK

    Directory of Open Access Journals (Sweden)

    Juan D Velásquez

    2008-12-01

    Full Text Available Una red neuronal autorregresiva es estimada para el precio mensual brasileño de corto plazo de la electricidad, la cual describe mejor la dinámica de los precios que un modelo lineal autorregresivo y que un perceptrón multicapa clásico que usan las mismas entradas y neuronas en la capa oculta. El modelo propuesto es especificado usando un procedimiento estadístico basado en el contraste del radio de verosimilitud. El modelo pasa una batería de pruebas de diagnóstico. El procedimiento de especificación propuesto permite seleccionar el número de unidades en la capa oculta y las entradas a la red neuronal, usando pruebas estadísticas que tienen en cuenta la cantidad de los datos y el ajuste del modelo a la serie de precios. La especificación del modelo final demuestra que el precio para el próximo mes es una función no lineal del precio actual, de la energía afluente actual y de la energía almacenada en el embalse equivalente en el mes actual y dos meses atrás.An autoregressive neural network model is estimated for the monthly Brazilian electricity spot price, which describes the prices dynamics better than a linear autoregressive model and a classical multilayer perceptron using the same input and neurons in the hidden layer. The proposed model is specified using a statistical procedure based on a likelihood ratio test. The model passes a battery of diagnostic tests. The proposed specification procedure allows us to select the number of units in hidden layer and the inputs to the neural network based on statistical tests, taking into account the number of data and the model fitting to the price time series. The final model specification demonstrates that the price for the next month is a nonlinear function of the current price, the current energy inflow, and the energy saved in the equivalent reservoir in the current month and two months ago.

  5. Casos de formación e investigación en el área del movimiento educativo abierto usando tecnologías emergentes en Latinoamérica

    OpenAIRE

    Ramírez Montoya, María Soledad

    2013-01-01

    1. A manera de introducción: El movimiento educativo abierto; 2. Tecnologías emergentes en la educación de acceso abierto; 3. Casos prácticos de formación e investigación en el área del movimiento educativo abierto usando tecnologías emergentes; 4. Retos y oportunidades para avanzar en el movimiento educativo abierto; Referencias bibliográficas

  6. Aussprache als motorische Fertigkeit

    DEFF Research Database (Denmark)

    Bonner, Maria

    2013-01-01

    Authentische Aussprache gilt im Fremdsprachenunterricht als schwer erreichbares Ziel, fremdsprachlicher Akzent wird als nahezu unvermeidbar gesehen. Weder die Hypothese einer kritischen Periode für den Erwerb einer authentischen Aussprache noch das Konzept der Fossilierung im Sprachlernprozess...

  7. Amyotrophic Lateral Sclerosis (ALS)

    Science.gov (United States)

    ... benefit of 16 months before onset of severe respiratory failure. Other treatments are designed to relieve symptoms and ... of ALS. Most people with ALS die from respiratory failure, usually within 3 to 5 years from the ...

  8. Initial Symptoms of ALS

    Science.gov (United States)

    ... Chapters Certified Centers and Clinics Support Groups About ALS About Us Our Research In Your Community Advocate ... Diagnosis En español Symptoms The initial symptoms of ALS can be quite varied in different people. One ...

  9. Utilidade do Ultrassom intracardíaco no isolamento de veias pulmonares usando cateter-balão a laser Utilidad del ultrasonido intracardíaco en el aislamiento de venas pulmonares usando catéter-balón láser Utility of intracardiac ultrasound imaging to guide pulmonary vein ablation using laser balloon catheter

    OpenAIRE

    Luiz Leite; Wilber Su; Johnson, Susan B.; Mark Milton; Benhur Henz; Alvaro Sarabanda; Santos, Simone N.; Packer, Douglas L.

    2009-01-01

    FUNDAMENTO: O isolamento das veias pulmonares (IVP) tem sido usado como endpoint para a ablação da fibrilação atrial (FA) com cateter balão. OBJETIVO: Determinar a utilidade do ultrassom intracardíaco (USIC) para guiar o IVP, usando cateter balão a laser. MÉTODOS: 59 VP foram ablacionadas em 27 cães. Imagens de Doppler foram usadas para identificar os vazamentos do fluxo sanguíneo entre a VP e o balão. Após cada liberação de energia, o cateter de mapeamento circular foi reposicionado para ver...

  10. Avaliação de opções de swing em contratos de gás natural usando um modelo de dois fatores

    Directory of Open Access Journals (Sweden)

    Carlos Patricio Samanez

    2014-12-01

    Full Text Available No mercado de gás natural (GN, muitos contratos incorporam flexibilidades no volume, conhecidas como opções de swing, as quais concedem ao titular a opção de exercer o direito de receber volumes maiores ou menores, de acordo com o mercado. Neste artigo, o preço do GN é a principal fonte de incerteza e foi modelado com um processo estocástico seguindo o modelo de dois fatores de Schwartz e Smith (2000 ao qual foi incorporada a sazonalidade trimestral. Para estimar os preços à vista do GN, usando os preços dos contratos futuros do Henry Hub, implementou-se o filtro de Kalman. O apreçamento da opção foi realizado através do modelo de árvore binomial bivariável desenvolvido por Hahn e Dyer (2011. O valor da opção de swing foi positivo nos dois casos analisados, mostrando que essa opção tem valor e deve ser analisada para inclusão nos contratos de GN. As características do contrato analisado foram as mesmas especificadas em Jaillet, Ronn e Tompaidis (2004.

  11. DelPapa - Aplicativo computacional para a análise de dados de experimentos no delineamento blocos ao acaso, usando o método Papadakis

    Directory of Open Access Journals (Sweden)

    Lindolfo Storck

    2015-05-01

    Full Text Available O aplicativo computacional para a análise de dados de experimentos executados no delineamento blocos ao acaso, por meio do método usual e de Papadakis, foi desenvolvido em sua primeira versão (não publicada, na linguagem de programação Pascal. Considerando que o método de Papadakis foi eficiente para as principais culturas agrícolas (milho, soja, feijão e trigo e, para tornar o aplicativo mais amigável, a versão em Pascal foi reprogramada em Java, cuja denominação é DelPapa. Este aplicativo realiza a análise de variância segundo o delineamento blocos ao acaso pelo método usual (estima parâmetros genéticos, medidas de qualidade experimental e testes dos pressupostos da análise de variância e pelo método de Papadakis. Usando as médias ajustadas pela covariável (média dos erros das parcelas vizinhas, também realiza o teste Scott e Knott (P=0,05 para agrupar os tratamentos.

  12. Maximización de captura de energía en turbinas eólicas de velocidad variable usando control proporcional integral generalizado

    Directory of Open Access Journals (Sweden)

    Horacio Coral-Enríquez

    2014-01-01

    Full Text Available En este artículo se propone una técnica alternativa de control lineal para maximizar la energía eólica capturada en una turbina eólica de eje horizontal. La estrategia propuesta se basa en técnicas de control proporcional integral generalizado ( GPI soportadas bajo el enfoque del rechazo activo de perturbaciones, que permite seguir de forma asintótica una trayectoria de referencia óptima de la velocidad del rotor sin el conocimiento exacto del modelo de la turbina eólica. La maximización de captura de energía se centra en mantener la velocidad específica de la turbina en su valor óptimo, por medio del control de la velocidad del rotor sobre una trayectoria óptima, en el cual el coeficiente de potencia es máximo. La metodología propuesta es validada mediante simulación usando una turbina eólica de 4,8 MW y comparada con una estrategia de control de par estándar. Los resultados muestran que las estrategias GPI propuestas son efectivas en términos de robustez y captura de energía.

  13. Significado que le asigna la Madre al cuidado cultural de ella misma y su recién nacido durante el puerperio a partir de sus prácticas y creencias

    OpenAIRE

    Prieto Bocanegra, Briyitd Migdolia

    2012-01-01

    Este estudio buscó describir el significado que le asigna la madre al cuidado cultural de ella misma y su recién nacido durante el puerperio, a partir de sus prácticas, y creencias en un grupo de mujeres en la ciudad de Tunja Boyacá. Con abordaje cualitativo de tipo etnográfico con participación de ocho puérperas, y cuatro informantes generales conformadas por profesionales de enfermería y familiares de las puérperas. Los datos fueron analizados usando la guía para el análisis de datos de Etn...

  14. Estimación de la resistencia a la penetración de suelos usando redes neuronales artificiales

    Directory of Open Access Journals (Sweden)

    Valdés Holguín Nidia Johana

    2011-09-01

    Full Text Available Las redes neuronales artificiales, simuladoras del proceso de aprendizaje de las neuronas biológicas, han sido utilizadas con éxito en el cálculo de parámetros en diversos problemas de ingeniería en que las variables involucradas tienen una alta relación no lineal entre sí y la modelación no permite representar el problema mediante una función matemática de fácil deducción. En la ciencia del suelo la predicción de algunas propiedades involucra diversas variables que hacen de su estimación por medio de modelos matemáticos un proceso complejo, y trasladan la solución del problema al campo de la inteligencia artificial. En el presente articulo se reporta la elaboración de redes neuronales artificiales para la estimación de la resistencia a la penetración a diferentes profundidades de un suelo; se consideran como variables infiuyentes el contenido de humedad, la densidad, la carga estãtica y la presión de infiado. Los resultados muestran una mejor estimación para profundidades entre 20 cm y 30 cm.

  15. PRUEBA CUANTITATIVA PARA PROTEASAS USANDO PELÍCULAS FOTOGRÁFICAS Quantitative Protease Assay Using Photographic Films

    Directory of Open Access Journals (Sweden)

    ANDREA PAREJA

    Full Text Available Se han desarrollado dos métodos para la medición cuantitativa de la actividad proteasa basados en la prueba de la película fotográfica. Una prueba discontinua puede ser implementada mediante la cuantificación de la cantidad de pigmento remanente en la película con cualquier programa de edición de imágenes. La medición continua de la actividad proteasa se puede obtener a través del cambio de absorbancia generado por la liberación de las sales de plata unidas al negativo fotográfico si se cuenta con un espectrofotómetro equipado con una celda con agitación.Two quantitative protease assays have been developed based on the classic photographic film test. A discontinuous assay can be performed by measuring the amount of pigment remaining in the film with any image editor software. A continuous assay can be implemented by the measuring the release of silver halide salts bonded in the film using a recording spectrophometer equipped with a Peltier Cell.

  16. Estimación de la resistencia a la penetración de suelos usando redes neuronales artificiales

    Directory of Open Access Journals (Sweden)

    Nidia Johana Valdés Holguín

    2011-07-01

    Full Text Available Las redes neuronales artificiales, simuladoras del proceso de aprendizaje de las neuronas biológicas, han sido utilizadas con éxito en el cálculo de parámetros en diversos problemas de ingeniería en que las variables involucradas tienen una alta relación no lineal entre sí y la modelación no permite representar el problema mediante una función matemática de fácil deducción. En la ciencia del suelo la predicción de algunas propiedades involucra diversas variables que hacen de su estimación por medio de modelos matemáticos un proceso complejo, y trasladan la solución del problema al campo de la inteligencia artificial. En el presente artículo se reporta la elaboración de redes neuronales artificiales para la estimación de la resistencia a la penetración a diferentes profundidades de un suelo; se consideran como variables influyentes el contenido de humedad, la densidad, la carga estática y la presión de inflado. Los resultados muestran una mejor estimación para profundidades entre 20 cm y 30 cm.

  17. ¿Por qué se está usando otra vez la talidomida? Why is thalidomide back?

    Directory of Open Access Journals (Sweden)

    Emilio Sanín Pérez

    2004-02-01

    Full Text Available En 1998 la Administración Federal para Medicamentos y alimentos de los Estados Unidos de América (FDA aprobó la comercialización (con restricciones de la talidomida para el tratamiento del Eritema nodoso asociado a la lepra. Brasil y México también han reglamentado su uso. Dado que actualmente se utiliza este fármaco teratogénico en enfermedades reumatológicas, dermatológicas, infecciosas y neoplásicas, se impone actualizar al médico general y al especialista, en los tópicos más relevantes del principio activo y sus efectos benéficos y deletéreos. Materiales y métodos: Se realizó una revisión textual mediante la lectura y análisis de los ensayos clínicos controlados, las series de casos y las revisiones de tema concernientes a la talidomida y sus posibles usos, reseñados en Medline entre enero de 1993 y diciembre de 2003, con el fin de extraer indicaciones y contraindicaciones a la luz de las pruebas que en ellos se describen. Además, se revisaron algunos informes de estudios anteriores a 1993, considerados de utilidad en el análisis. Resultados: Se encontraron 46 ensayos controlados aleatorizados y se revisaron 22 con al menos 50 pacientes al inicio del estudio; además, se analizaron 22 series de casos y 10 revisiones de tema que permiten conocer las indicaciones del uso de la talidomida en humanos, las bases farmacocinéticas que explican los efectos benéficos y/o deletéreos y las recomendaciones tendientes a garantizar que no se repita la teratogénesis. Conclusión: Se dispone de la talidomida, con restricciones, para el tratamiento del Eritema nodoso lepromatoso (primera línea y del Mieloma múltiple refractario a la quimioterapia múltiple. Parece tener efectos benéficos en muchas otras condiciones graves y refractarias a enfoques de primera línea: SIDA, cáncer de esófago, cáncer de próstata y algunas dermatosis severas, reumatológicas o no. No debe recomendarse en pacientes con Epidermolisis necrótica t

  18. Teleoperación de un Servomecanismo a Través de un Mundo Virtual Usando Una Interfaz Gestual

    Directory of Open Access Journals (Sweden)

    Luz Santamaría-Granados

    2015-07-01

    Full Text Available Este artículo presenta los resultados de investigación del desarrollo de un prototipo que permite el accionamiento real a distancia de un servomecanismo mediante un mundo virtual controlado por una interfaz gestual. La metodología de investigación formula cuatro fases: la interfaz gestual que utiliza los algoritmos de CamShift y MeanShift para la identificación de la orden que se le envía al robot; la comunicación inalámbrica recibe la instrucción de la interfaz gestual para la teleoperación del robot; el mundo virtual que simula el recorrido del avatar en el ambiente lunar, tal como lo realiza el robot en el mundo real; finalmente se plantea la construcción del sistema eléctrico y mecánico del servomecanismo. Este proyecto puede ser referente para el desarrollo de sistemas de teleoperación que permitan la experimentación remota y virtual de desastres naturales o ambientes que generan riesgo para la vida humana.

  19. Red Neuronal Creciente Usando Perturbación Simultánea Growing Cell Neural Network using Simultaneous Perturbation

    Directory of Open Access Journals (Sweden)

    G. Sánchez

    2004-01-01

    Full Text Available Este artículo propone una red neuronal de tipo perceptron multicapas (MLP que optimiza tanto su matriz de pesos como el número de neuronas ocultas. Inicialmente el sistema propuesto usa un número reducido de neuronas ocultas, optimizándose la matriz de pesos mediante un algoritmo de perturbación simultánea. Una vez que la red converge se analiza su funcionamiento y si este no es el esperado se agrega una neurona oculta. Este proceso se repite hasta obtener el funcionamiento deseado. Los resultados obtenidos muestran que el sistema propuesto presenta un funcionamiento muy similar al de un MLP convencional, cuando éste tiene un número óptimo de nodos en la capa oculta y disminuye la complejidad computacional durante la etapa de entrenamiento.This paper proposes a multilayer perceptron neural network (MLP which optimizes both the matrix weights and the numbers of hidden neurons. Initially, the proposed system uses a reduced number of hidden neurons, optimizing the matrix weights by using a simultaneous perturbation algorithm. Once the network converges, its function is analyzed and if this is not as expected, a hidden neuron is added. This process is repeated until achieving the desired functioning. The results obtained show that the proposed system functions similarly to that of a conventional MLP when this has an optimal number of nodes in the hidden layer, decreasing the computational complexity during the training step.

  20. Volver al desarrollo

    Directory of Open Access Journals (Sweden)

    Jaime Ornelas Delgado

    2012-01-01

    Full Text Available El desarrollo, categoría empleada para expresar el crecimiento económico, surge durante la "guerra fría" y si bien fue propuesta por teóricos metropolitanos, se asumió en Latinoamérica como parte de los instrumentos disponibles para lograr el crecimiento y alternativa al socialismo. El desarrollo mantuvo su vigencia entre 1945 y 1975, cuando al advenimiento del neoliberalismo fue paulatinamente retirado de la agenda de las preocupaciones nacionales e internacionales. Al iniciarse el siglo xxi, el fracaso del mercado autorregulado trajo de nueva cuenta al debate los problemas del desarrollo, lo que obliga a revisarlo críticamente, tanto como al concepto mismo para mostrar su carácter colonial, si se quiere construir caminos ajenos al neoliberal y superar los problemas que han hecho de Latinoamérica una de las regiones más desiguales del mundo.

  1. Jalta als Heterotopie

    OpenAIRE

    Schmid, Ulrich

    2013-01-01

    Jalta ist ein Ort, der sich im europäischen Kulturgedächtnis sowohl historisch als auch literarisch als "radikal anderer Ort" - als " Heterotopie" - festgesetzt hat. An der Konferenz von Jalta wurde 1945 eine neue Weltordnung geschaffen in der Hoffnung auf eine bessere Welt. Auch in den Werken von Anton ?echov, vor allem in denjenigen, die in Jalta entstanden sind, wird von einer anderen und besseren Welt geträumt.

  2. Pornographie als Metapher

    Directory of Open Access Journals (Sweden)

    Caroline Schubarth

    2010-02-01

    Full Text Available In diesem Artikel werden unterschiedliche metaphorische Verwendungen des Pornografiebegriffs und deren Implikationen untersucht. Während die Existenz von Pornografie der feministischen Anti-Porno-Bewegung als Erklärung für die anhaltende Diskriminierung von Frauen in westlichen Gesellschaften dient, nutzen rechtskonservative Kräfte den Pornografievorwurf als Rechtfertigung für die Zensur von als deviant empfundenen Identitäten und sexuellen Praktiken.

  3. Pornographie als Metapher

    OpenAIRE

    Caroline Schubarth

    2010-01-01

    In diesem Artikel werden unterschiedliche metaphorische Verwendungen des Pornografiebegriffs und deren Implikationen untersucht. Während die Existenz von Pornografie der feministischen Anti-Porno-Bewegung als Erklärung für die anhaltende Diskriminierung von Frauen in westlichen Gesellschaften dient, nutzen rechtskonservative Kräfte den Pornografievorwurf als Rechtfertigung für die Zensur von als deviant empfundenen Identitäten und sexuellen Praktiken.This article...

  4. Sobre Al-Qarmuniyya

    OpenAIRE

    Fierro Bello, María Isabel

    1990-01-01

    [ES] En dos tradiciones escatológicas relativas a al-Andalus y recogidas por 'Abd al-Malik h Haha en su Ta'rg se hace referencia a Carmona. La mención de esta ciudad en dichas tradiciones debe ser puesta en relación con dos episodios de la historia de al-Andalus que tuvieron lugar antes de la muerte de Ibn Habib: la batalla de Carmona en época de 'Abd al-Rahman y la concentración de tropas omeyas en el mismo lugar durante el ataque normando en los años 229-30/844-5.

  5. Variantes del problema del cartero mixto que se pueden resolver usando programación lineal Variants of the mixed postman problem solvable using linear programming

    Directory of Open Access Journals (Sweden)

    Francisco Javier Zaragoza Martínez

    2012-07-01

    Full Text Available Dada una gráfica mixta y conexa con costos en sus aristas y arcos, el problema del cartero mixto consiste en encontrar un circuito cerrado de la gráfica mixta que recorra sus aristas y arcos a costo mínimo. Se sabe que este problema es NP-duro. Sin embargo, bajo ciertas condiciones adicionales, el problema se puede resolver en tiempo polinomial usando programación lineal, en otras palabras, los poliedros correspondientes son enteros. Algunas de estas condiciones son: la gráfica mixta es serie paralelo o la gráfica mixta tiene grado total par en todos sus vértices. Además, mostramos que si agregamos la restricción adicional de que cada arista se recorra exactamente una vez entonces el problema se puede resolver en tiempo polinomial si el conjunto de arcos forma un bosque.Given a connected mixed graph with costs on its edges and arcs, the mixed postman problem consists of finding a minimum cost closed tour of the mixed graph traversing all of its edges and arcs. It is well-known that this problem is NPhard. However, under certain conditions, the problem can be solved in polynomial time using linear programming, in other words, the corresponding polyhedra are integral. Some of these conditions are: the mixed graph is series-parallel or the mixed graph is even. Also, we show that if we add the constraint that each edge is traversed exactly once then the problem can be solved in polynomial time if the set of arcs forms a forest.

  6. Infecção cirúrgica em colecistectomia videolaparoscópica usando ácido peracético como esterilizante dos instrumentais

    Directory of Open Access Journals (Sweden)

    Edluza Maria Viana Bezerra de Melo

    2013-06-01

    Full Text Available OBJETIVO: Determinar a frequência de infecção de sítio cirúrgico em pacientes submetidos à colecistectomia videolaparoscópica usando o ácido peracético como esterilizante. MÉTODOS: Foi realizado estudo retrospectivo descritivo do tipo coorte transversal. O ácido peracético foi usado para esterilização seguindo protocolo preconizado pelo fabricante. Foram observados os critérios e indicadores de processo e estrutura para prevenção de infecção de sítio cirúrgico no pré e intraoperatório. Para a vigilância epidemiológica, consultas ambulatoriais eram agendadas para o 15º e entre o 30º e 45º dias após a alta. RESULTADOS: Entre 247 pacientes foram diagnosticados dois casos de infecção de sítio cirúrgico (0,8%. Um paciente reinternou para antibioticoterapia sistêmica e punção percutânea; no outro, a infecção foi superficial e acompanhada ambulatorialmente. CONCLUSÃO: Eticamente não é permitida a realização de um estudo prospectivo pelo fato do ácido peracético ter sido proibido para a esterilização de instrumentais que penetrem em órgãos e cavidades; contudo, estes resultados encorajam estudo prospectivo caso-controle, comparando o uso dele (controle histórico com a esterilização por óxido de etileno.

  7. Compósitos polímero-madeira preparados por polimerização in situ de metil metacrilato usando aditivos bifuncionais

    Directory of Open Access Journals (Sweden)

    Bruno Dufau Mattos

    2015-12-01

    Full Text Available Resumo O presente trabalho teve por objetivo a confecção de compósitos polímero-madeira por meio de polimerização in situ de metil metacrilato (MMA, utilizando ácido metacrílico (MAA e glicidil metacrilato (GMA como agentes de ligação e reticulação. Amostras de madeira de guapuruvu foram impregnadas em um sistema de vácuo e pressão e polimerizadas em estufa a 90°C por 10h, usando 1,5% de peroxido de benzoíla como catalisador. Os compósitos foram caracterizados por meio de testes de absorção de água e estabilidade dimensional, molhabilidade, ATR-IR, TGA, MEV e WPG. Os espectros de ATR-IR mostraram incrementos nas bandas a 1746, 1460, e 1145 cm–1, referentes as estruturas químicas dos polímeros dentro da madeira, confirmado posteriormente pelas imagens de MEV. A termogravimetria apontou reações químicas entre os copolímeros e a parede celular da madeira nos compósitos com GMA e MAA. Os compósitos preparados com MMA apresentaram incrementos acima de 50% nas propriedades higroscópicas e de estabilidade dimensional, entretanto a adição de GMA e MAA resultou em maiores incrementos nas mesmas propriedades, entre 66-90%.

  8. Análise da eficiência do mercado futuro brasileiro de boi gordo usando co-integração

    Directory of Open Access Journals (Sweden)

    André Steffens Moraes

    2009-09-01

    Full Text Available A hipótese de que os preços futuros são preditores não viesados dos preços à vista é uma hipótese conjunta de que os mercados são eficientes e que não existe prêmio ao risco. Entretanto, na presença de prêmio ao risco, a hipótese de não viés pode ser rejeitada mesmo quando o mercado é eficiente. Este artigo testa a eficiência do mercado futuro brasileiro do boi gordo na presença de prêmio ao risco, usando técnicas de co-integração. Os resultados mostram que o mercado futuro do boi gordo é eficiente e não viesado no longo prazo, independente da presença de prêmio ao risco.The hypothesis that future prices are unbiased predictors of spot prices is a joint hypothesis that markets are efficient and risk premium are absent. However, the unbiasedness hypothesis may be rejected in the presence of a risk premium, even when the market is efficient. The objective of this article is to test market efficiency for the Brazilian live cattle while permitting the presence of risk premium, using cointegration techniques. Results show that the future markets for live cattle are efficient and unbiasedness in the long run, and does not depend of the presence of a risk premium.

  9. Análisis mecánico y tribológico de los recubrimientos fe-cr-ni-c y ni-al-mo

    OpenAIRE

    MUÑOZ, JORGE E.; JOHN J. CORONADO

    2008-01-01

    En este trabajo de investigación se evaluaron dos recubrimientos aplicados por medio de la técnica de rociado térmico por combustión, la aleación: Ni=89%, Al = 5,5%, Mo=5,5% y la aleación Fe=81,8%, Cr=16%, Ni=2%, C=0,2. La preparación superficial de las probetas se realizó usando chorro de arena. Se realizaron pruebas de resistencia al cortante, adherencia, desgaste abrasivo, desgaste por deslizamiento y flexión en cuatro puntos. El recubrimiento Fe-Cr-Ni-C presentó menor pérdida de masa, tan...

  10. Al-Anon/Alateen

    Science.gov (United States)

    Find an Al-Anon meeting Español | Français 2018 Int'l Convention Home About Group Meetings What If I'm not ready ... a meeting? What can I expect at an Al-Anon meeting? What was my first meeting like? ...

  11. Al - BASED CAST COMPOSITES

    Directory of Open Access Journals (Sweden)

    Rakesh Kumar Yadav

    2011-08-01

    Full Text Available The economy is very important feature nowadays in themarket. The researches are playing an important role inengineering field to increase the life of machine parts /components and decrease the cost. The compositematerials have the potential to replace widely used steeland aluminium due to their good characteristics withbetter performance. The Al-based composites have foundextensive applications in automobile industries andaerospace industries due to their increased stiffness,strength, thermal conductivity and wear resistanceproperties. A number of particulate phases have beenemployed in the Al-alloy matrix. The cast aluminiumceramicparticulate composites are finding applications inpistons, connecting rods, cylinder liner, engine cylinderblock, electrical contacts etc.The present investigation isbased on study of the effect of particulate phase on theSEM study, micro-hardness, elastic modulus, tensilestrength and the wear behaviour of Al-5 % SiC-7 % Fe,Al-10 % SiC-6 % Fe and Al-15 % SiC-5 % Fe composites.

  12. Immunoblot analysis using antigen from Taenia crassiceps cysticerci in the diagnosis of swine cysticercosis Análisis del inmunoblot usando antígeno de cisticercos de Taenia crassiceps en el diagnóstico de la cisticercosis

    OpenAIRE

    Paulo Sérgio de Arruda Pinto; Adelaide José Vaz; Paulo Mutuko Nakamura; Pedro Manuel Leal Germano

    2001-01-01

    Se utilizó la técnica del inmunoblot para el diagnóstico de la cisticercosis porcina usando un antígeno total de cisticercos de Taenia crassiceps. Fueron analizados 13 sueros del cerdo con cisticercosis, 30 sueros controles negativos y ocho sueros del cerdo con hidatidosis, así como nueve del suino con macracantorincosis, 10 con ascaridiosis y ocho con pulmonía. El uso de este antígeno en el inmunoblot con suero de cerdos no se había publicado previamente. El inmunoblot fue padronizado por an...

  13. Diseño e implementación de una herramienta para analizar imágenes extraídas de redes sociales, usando la librería OpenCV

    OpenAIRE

    Ramos Alférez, Albert

    2015-01-01

    Diseño de una aplicación web que permite extraer información de redes sociales e internet para reconocimiento de personas desaparecidas Design and implementation of a tool for analyzing images taken from social networks, using the OpenCV library Diseño e implementación de una herramienta para analizar imágenes extraídas de redes sociales, usando la librería OpenCV Disseny e implementació d'una eina per analitzar imatges extretes de les xarxes socials, utilitzant la llibrería OpenCV...

  14. Comparison of the interface dentin-endodontic sealer using two SEM magnifications = Comparação da interface dentina-cimento endodôntico usando dois aumentos de MEV

    OpenAIRE

    Steier, Liviu; de Figueiredo, José Antonio Poli; Belli, Sema

    2010-01-01

    Objetivo: Este estudo teve por objetivo comparar a interface dentina – cimento endodôntico de dois cimentos (RealSeal e AH Plus) usando dois aumentos de Microscopia Eletrônica de Varredura (MEV). Metodologia: Os dois terços coronários de oito molares extraídos foram removidos e as superficies dentinárias foram desgastadas com o uso sequencial de lixas abrasivas 180 e 320, sob refrigeração a água. Os espécimes foram divididos em dois grupos com quatro espécimes cada de acordo com o cimento ...

  15. Estudio de fallas incipientes en rodamientos usando la técnica de la envolvente y cepstrum Study on incipient fault bearing detection based on enveloping and cepstrum techniques

    OpenAIRE

    Quiroga, Jabid E.; Gerson Trujillo; Sergio Quintero

    2012-01-01

    Este artículo presenta un estudio comparativo del desempeño de los métodos de detección de fallas incipientes en rodamientos FFT, envolvente y cepstrum usando señales de vibración. Diferentes condiciones de fallas son estudiadas, desde incipientes hasta severas a través de un banco de prueba construido para ese propósito. Adicionalmente se utilizan registros de vibraciones obtenidos en el website (CWRU), de Case Western Reserve University, para evaluar el desempeño de las técnicas. Las técnic...

  16. [Environmental factors in ALS].

    Science.gov (United States)

    Juntas-Morales, Raul; Pageot, Nicolas; Corcia, Philippe; Camu, William

    2014-05-01

    ALS is likely to be a disorder of multifactorial origin. Among all the factors that may increase the risk of ALS, environmental ones are being studied for many years, but in the recent years, several advances have pointed to a new interest in their potential involvement in the disease process, especially for the cyanotoxin BMAA. Food containing BMAA has been found on Guam, a well-known focus of ALS/parkinsonism/dementia and high levels of BMAA have been identified into the brain of these patients. The BMAA cyanotoxin is potentially ubiquitous and have also been found into the food of patients who died from ALS both in Europe and USA. BMAA can be wrongly integrated into the protein structure during mRNA traduction, competing with serine. This may induce abnormal protein folding and a subsequent cell death. Heavy metals, such as lead or mercury may be directly toxic for neuronal cells. Several works have suggested an increased risk of ALS in individuals chronically exposed to these metals. Exposure to pesticides has been suggested to be linked to an increased risk of developing ALS. The mechanism of their toxicity is likely to be mediated by paraoxonases. These proteins are in charge of detoxifying the organism from toxins, and particularly organophosphates. To date, there are insufficient scientific data to suggest that exposure to electromagnetic fields may increase the risk of having ALS. We are particularly missing longitudinal cohorts to demonstrate that risk. PMID:24703731

  17. Comparação das técnicas transarterial e de estimulação de múltiplos nervos para bloqueio do plexo braquial por via axilar usando lidocaína com epinefrina Comparación de las técnicas transarterial y de estimulación de múltiples nervios para bloqueo del plexo braquial por vía axilar usando lidocaína con epinefrina Comparison of transarterial and multiple nerve stimulation techniques for axillary block using lidocaine with epinephrine

    Directory of Open Access Journals (Sweden)

    Luiz Eduardo Imbelloni

    2005-02-01

    resulta en alta efectividad para el bloqueo axilar del plexo braquial. La técnica de utilizar múltiples estímulos exige más tiempo y mayor experiencia. Este estudio prospectivo compara la latencia y el índice de éxito del bloqueo del plexo braquial usando dos técnicas de localización: transarterial o múltipla estimulación de los nervios. MÉTODO: La lidocaína con epinefrina, 800 mg, fue usada inicialmente para el bloqueo axilar. En el grupo transarterial, 30 mL de lidocaína a 1,6% con epinefrina fueron inyectados profundamente y 20 mL superficialmente a la arteria axilar. En el grupo de múltipla estimulación, tres nervios fueron localizados eléctricamente y bloqueados con volúmenes 20 mL, 20 mL y 10 mL de la solución. El bloqueo fue considerado efectivo cuando la analgesia estaba presente en todos los nervios en la área distal al codo. RESULTADOS: El tiempo de latencia (8,8 ± 2,3 min versus 10,2 ± 2,4 min; p-valor = 0,010 fue significativamente menor en el grupo transarterial. Bloqueos sensitivos completos en los cuatro nervios (mediano, ulnar, radial y musculocutáneo fueron logrados en un 92,5% versus 83,3% en el grupo de múltipla estimulación y acceso transarterial, respectivamente sin diferencia significativa (p-valor = 0,68. El nervio musculocutáneo fue significativamente más fácil de bloquear con el estimulador de nervio periférico (p = 0,034. CONCLUSIONES: La técnica de múltipla estimulación para el bloqueo axilar usando estimulador de nervios (3 inyecciones y la técnica transarterial (2 inyecciones producen resultados semejantes en la calidad del bloqueo. El nervio musculocutáneo es más facilmente bloqueado con el uso del estimulador del nervio periférico. La técnica de múltipla estimulación necesitó menor suplementación del bloqueo y aumentó el tiempo para el inicio de la cirugía.BACKGROUND AND OBJECTIVES: High-dose transarterial technique results in highly effective axillary block. The multiple nerve stimulation technique

  18. Sociale media als leermiddel

    NARCIS (Netherlands)

    Rubens, Wilfred

    2012-01-01

    Rubens, W. (2012, 5 juni). Sociale media als leermiddel. Presentatie over het gebruik van sociale media binnen het onderwijs, verzorgd tijdens een ouderraadbijeenkomst van de Katholieke Scholengemeenschap Etten-Leur, Etten-Leur, Nederland.

  19. MDA ALS Caregiver's Guide

    Science.gov (United States)

    ... R.D., C.N.S.D., L.D.N. Nutritionist MDA/ALS Center at Vanderbilt University Medical Center ... neurologists, physiatrists, therapists (physical, occupa- tional, speech, respiratory), nutritionists, social work- ers, pulmonologists, gastroenterologists and medical equipment ...

  20. Regionale Herkunft als Bonus

    OpenAIRE

    Kratochvil, Dr. Ruth

    2004-01-01

    Der Bio-Sektor durchlebt bewegte Zeiten. Die biologische Landwirtschaft hat sich aus der Nische herausbewegt und dafür an „Besonderheiten“ eingebüßt. Diese müssen als Zusatznutzen wiedergefunden werden.

  1. Factores asociados al bajo peso al nacer

    OpenAIRE

    Georgina J Peraza Roque; Silvia de la C Pérez Delgado; Zoe de los A Figueroa Barreto

    2001-01-01

    El bajo peso al nacer (BPN) ha constituido un enigma en la ciencia a través de los tiempos. Múltiples son las investigaciones realizadas acerca de las causas que lo producen y las consecuencias que provoca. Su importancia no solo radica en lo que significa en la morbilidad y la mortalidad infantil, sino que estos niños tienen habitualmente múltiples problemas posteriores. El Programa para la Reducción del BPN señala que los niños nacidos con un peso inferior a los 2 500 g presentan riesgo de ...

  2. Partizipation als Ausnahmezustand

    OpenAIRE

    Korf, Benedikt

    2009-01-01

    In «Die Erfindung des Politischen» (1993) beschreibt Ulrich Beck Subpolitik als den Ort, an dem die Grenze zwischen Politik und Nichtpolitik verschwindet. Aus der zunehmenden Wirkkraft von Subpolitik erwächst die grundlegende Frage, mit welcher Legitimation diese Art von Subpolitik in die Sphäre der institutionalisierten Politik eindringt. Beck’s Subpolitik soll im Anschluss an theoretische Arbeiten von Chantal Mouffe und Giorgio Agamben als post-politische Aspiration bezeichnet werden, die e...

  3. End-to-side nerve repair using fibrin glue in rats Anastomose nervosa término-lateral usando cola de fibrina em ratos

    Directory of Open Access Journals (Sweden)

    Daniel Nunes e Silva

    2010-04-01

    Full Text Available PURPOSE: To evaluate axonal regeneration after end-to-side nerve repair with fibrin glue in rats. METHODS: Forty-five Wistar rats were divided into three groups: group A (n=15, were not submitted to surgery (control group; group B (n=15 were submitted to fibular transection without repair; and group C (n=15, were submitted to fibular transection with end-to-side nerve anastomosis using fibrin glue, in the lateral surface of an intact tibial nerve. The three groups were submitted to walking track (30 and 90 days and posterior morphometrical analysis (90 days. RESULTS: The functional tests demonstrated that there was no difference in the walking track during the study in group A (p>0.05. The group B had walking pattern impairment in the two tests (p>0.05. The group C had walking pattern impairment in the first test, with important recovery in the second test (pOBJETIVO: Avaliar a regeneração axonal após anastomose nervosa término-lateral (ATL usando cola de fibrina em ratos. MÉTODOS: Quarenta e cinco ratos Wistar distribuídos em três grupos: os animais do grupo A (n=15 não foram submetidos à secção nervosa (grupo controle; os animais do grupo B (n=15 foram submetidos apenas à secção do nervo fibular, sem posterior anastomose; e os animais do grupo C (n=15 foram submetidos à secção do nervo fibular e à ATL com cola de fibrina no nervo tibial. Posteriormente, os animais foram submetidos a dois testes de marcha (30 e 90 dias e à análise morfométrica (90 dias. RESULTADOS: A análise estatística dos testes de marcha demonstrou que o grupo A não apresentou alteração no padrão de caminhada durante o estudo (p>0,05. O grupo B apresentou prejuízo motor no primeiro e no segundo teste (p>0,05. O grupo C apresentou um padrão de atrofia no primeiro teste, com recuperação da marcha no segundo teste (p<0,05. Na análise morfométrica, o grupo C apresentou regeneração axonal significativamente superior ao grupo B (p<0,05. CONCLUS

  4. Autoconceito dos professores: principais factores usando modelos de Análise de Dados Multivariada Teachers' self-concept: finding main factors and clusters by EDA models

    Directory of Open Access Journals (Sweden)

    Vitor Franco

    2008-01-01

    Full Text Available O autoconceito tem sido considerado uma dimensão muito importante da personalidade do professor, da sua prática e do seu desenvolvimento pessoal (MARKUS; WURF, 1987; SIMÕES, 2001. A investigação que apresentamos foi efectuada com 281 professores de Ciências da Natureza, do terceiro ciclo do Ensino Básico, em Portugal, usando o ICAC- Inventário Clínico do Auto Conceito (VAZ-SERRA, 1986. Na análise dos dados obtidos foram usados diferentes métodos de Análise Multivariada, apresentando-se os resultados da análise factorial de correspondências e nos modelos de classificação hierárquica baseados no coeficiente de afinidade. Os resultados obtidos: 1 confirmam a importância de dois grandes factores presentes no Autoconceito: aceitação social e auto-eficácia; 2 caracterizam estes principais factores no que se refere ao Autoconceito clínico dos professores; 3 mostram como esses factores são determinantes na forma como cada professor constroi o seu autoconceito.The self-concept has been considered as a very important dimension on teacher's personality, practice and development (MARKUS; WURF, 1987;SIMÕES, 2001. The present research concerns a sample of 281 teachers of Natural Science of the Third Cycle of Basic Education from Portugal that responded to the I.C.A.C. - Self-Concept Clinical Inventory (VAZ-SERRA, 1986. In the analysis of the questionnaires different multivariate data analysis methods have been used. This paper describes some results issued from correspondence analysis and hierarchical clustering models based on the affinity coefficient. The results obtained: 1 confirm the importance of two general main factors / types which are present in self-concept: social acceptance and self-efficiency; 2 characterise these main factors when teachers'clinical self-concept is concerned and 3 show how determinant these factors are for the building of self-concept that allow us to differentiate teachers.

  5. PREDICCIÓN DE SERIES TEMPORALES USANDO MÁQUINAS DE VECTORES DE SOPORTE TIME SERIES PREDICTION USING SUPPORT VECTOR MACHINES

    Directory of Open Access Journals (Sweden)

    Juan D Velásquez

    2010-04-01

    Full Text Available La predicción de series de tiempo es un importante problema de investigación debido a sus implicaciones en ingeniería, economía, finanzas y ciencias sociales. Un importante tópico de esta problemática es el desarrollo de nuevos modelos y su comparación con aproximaciones previas en términos de la precisión del pronóstico. Recientemente, las máquinas de vectores de soporte (SVM han sido usadas para la predicción de series de tiempo, pero las experiencias reportadas son limitadas y hay algunos problemas relacionados con su especificación. El objetivo de este artículo es proponer una técnica novedosa para estimar algunas constantes en las SVM que usualmente son fijadas en forma empírica por el modelador. La técnica propuesta es usada para estimar varias SVM con el fin de pronosticar cinco series benchmark; los resultados obtenidos son comparados con las estadísticas reportadas en otros artículos. La metodología propuesta permite obtener SVM competitivas para las series pronosticadas en comparación con los resultados obtenidos usando otros modelos más tradicionales.Time series prediction is an important research problem due to its implications in engineering, economics, finance and social sciences. An important topic about this problematic is the development of new models and its comparison with previous approaches in terms of forecast accuracy. Recently, support vector machines (SVM have been used for time series prediction, but the reported experiences are limited and there are some problems related to its specification. The aim of this paper is to propose a novel technique for estimating some constants of the SVM usually fixed empirically by the modeler. The proposed technique is used to estimate several SVM with the aim of forecast five benchmark time series; the obtained results are compared with the statistics reported in other papers. The proposed method allow us to obtain competitive SVM for the time series forecasted

  6. Processing of red ceramic using a fast-firing cycle Processamento de cerâmica vermelha usando um ciclo de queima rápido

    Directory of Open Access Journals (Sweden)

    G. T. Saleiro

    2012-09-01

    Full Text Available This work reports on the processing of red ceramic for civil construction using fast-firing cycles. The firing cycle is an important variable in the processing of red ceramic materials, which contributes to a high consumption of energy. The red ceramic pieces were prepared by industrial extrusion and fired at firing temperatures varying from 700 ºC to 1100 ºC using different firing cycles (slow-firing cycle - 1º C/min and fast-firing cycle - 10 ºC/min and 20 °C/min. The technological properties (linear shrinkage, water absorption, apparent porosity, apparent density, and flexural strength as function of the firing temperature and firing cycle are investigated. The development of the microstructure was followed by SEM/SEI. The results showed that fast-firing red ceramics exhibits technological properties and microstructure comparable to conventionally fired red ceramics, resulting in great advantages in energy saving.Este trabalho descreve o processamento de cerâmica vermelha para construção civil usando ciclos de queima rápido. O ciclo de queima é uma variável importante no processamento de materiais de cerâmica vermelha, o qual contribui para um alto consumo de energia. As peças de cerâmica vermelha foram preparadas por extrusão industrial e queimadas nas temperaturas de queima variando de 700 ºC a 1100 ºC utilizando diferentes ciclos de queima (ciclo de queima lento - 1 ºC/min e ciclos de queima rápidos - 10 ºC/ min e 20 ºC/min. As propriedades tecnológicas (retração linear, absorção de água, porosidade aparente, massa específica aparente e tensão de ruptura à flexão em função da temperatura de queima e ciclo de queima são investigadas. O desenvolvimento da microestrutura foi avaliado por SEM/SEI. Os resultados mostraram que as peças de cerâmica vermelha obtidas via processo de queima rápida exibiram propriedades tecnológicas e microestrutura comparáveis àquelas convencionalmente obtidas via queima lenta

  7. Análisis de rendimiento académico estudiantil usando data warehouse y redes neuronales Analysis of students' academic performance using data warehouse and neural networks

    Directory of Open Access Journals (Sweden)

    Carolina Zambrano Matamala

    2011-12-01

    Full Text Available Cada día las organizaciones tienen más información porque sus sistemas producen una gran cantidad de operaciones diarias que se almacenan en bases de datos transaccionales. Con el fin de analizar esta información histórica, una alternativa interesante es implementar un Data Warehouse. Por otro lado, los Data Warehouse no son capaces de realizar un análisis predictivo por sí mismos, pero las técnicas de inteligencia de máquinas se pueden utilizar para clasificar, agrupar y predecir en base a información histórica con el fin de mejorar la calidad del análisis. En este trabajo se describe una arquitectura de Data Warehouse con el fin de realizar un análisis del desempeño académico de los estudiantes. El Data Warehouse es utilizado como entrada de una arquitectura de red neuronal con tal de analizar la información histórica y de tendencia en el tiempo. Los resultados muestran la viabilidad de utilizar un Data Warehouse para el análisis de rendimiento académico y la posibilidad de predecir el número de asignaturas aprobadas por los estudiantes usando solamente su propia información histórica.Every day organizations have more information because their systems produce a large amount of daily operations which are stored in transactional databases. In order to analyze this historical information, an interesting alternative is to implement a Data Warehouse. In the other hand, Data Warehouses are not able to perform predictive analysis for themselves, but machine learning techniques can be used to classify, grouping and predict historical information in order to improve the quality of analysis. This paper depicts architecture of a Data Warehouse useful to perform an analysis of students' academic performance. The Data Warehouse is used as input of a Neural Network in order to analyze historical information and forecast. The results show the viability of using Data Warehouse for academic performance analysis and the feasibility of

  8. Der Preis als Kaufbarriere?

    DEFF Research Database (Denmark)

    Mueller Loose, Simone

    2012-01-01

    Die Preispolitik hat eine herausragende Stellung im Marketing. Der Preis eines Produktes ist für Verbraucher ein direkter Kostenfaktor und für Unternehmen die Stellgröße im Mar-ketingmix, die den Umsatz am stärksten beeinflusst (vgl. Nieschlag et al. 2002). Wenn die Akzeptanz und der regelmäßige...... Verzehr gesunder Lebensmittel erhöht werden soll, ist es sowohl für die Verbraucherpolitik als auch für Lebensmittelproduzenten wichtig, den Ein-fluss des Preises auf die Kaufentscheidung zu verstehen. Aus Verbrauchersicht ist der Preis neben dem Geschmack die wichtigste Produkteigen-schaft beim Kauf von...... Lebensmitteln (vgl. Brunsø/Grunert 1998) und stellt eine Kaufbarrie-re für Lebensmittel mit gesundheitsfördernden Eigenschaften dar. Studien in den USA (vgl. Cassady et al. 2007), Frankreich (vgl. Drewnowski et al. 2004; Andrieu et al. 2005) und Deutschland (vgl. Karg et al. 2008) kommen übereinstimmend zu dem...

  9. Lesão brônquica e pneumotórax após reintubação usando um cateter para troca da via aérea Lesión brónquica y neumotórax posterior a la reintubación usando un catéter para el cambio de la vía aérea Bronchial injury and pneumothorax after reintubation using an airway exchange catheter

    Directory of Open Access Journals (Sweden)

    Juliano P. de Almeida

    2013-02-01

    por perforación brónquica durante una reintubación usando un catéter para el cambio de la vía aérea (CTVA en una paciente con cáncer de cabeza y cuello. RELATO DE CASO: Paciente del sexo masculino, 53 años, con carcinoma de orofaringe, que fue ingresado en la UTI con neumonía grave y el síndrome de la angustia respiratoria aguda (SARA. El paciente fue identificado como siendo de difícil intubación y con un broncoscopio se le insertó una sonda endotraqueal (SET. Después de una semana de tratamiento, vimos una ruptura del manguito endotraqueal. El cambio de la sonda endotraqueal se hizo necesario para obtener una ventilación pulmonar satisfactoria. Un catéter para el cambio de la vía aérea (Cook, tamaño 14 se usó para realizar la reintubación. Después de la reintubación, el paciente tuvo un empeoramiento en la saturación de oxígeno y una radiografía reveló un fuerte neumotórax. Un dreno torácico se insertó observando una mejoría inmediata en la saturación de oxígeno. La repetición de la radiografía confirmó el posicionamiento correcto del dreno torácico y la re-expansión del pulmón derecho. La broncoscopia realizada arrojó una laceración posterior del bronquio principal derecho. El paciente se desentubó al día siguiente. Después de cuatro días, el dreno torácico se retiró. La radiografía realizada un día después de la retirada del dreno reveló un pequeño neumotórax en el lóbulo superior derecho, pero el paciente permaneció asintomático. CONCLUSIONES: El catéter para el cambio de la vía aérea es una herramienta valiosa para lidiar con los pacientes difíciles de intubar. Aunque los médicos generalmente concentren su atención en evitar un barotrauma causado por el suplemento de oxígeno o ventilación a chorro por medio del CTVA, la preocupación con la técnica de inserción puede minimizar las complicaciones que amenazan la vida y aumentar la seguridad del CTVA.BACKGROUND AND OBJECTIVES: We report a case of

  10. Estimate potential evaporation and solar radiation in the Yaqui valley, Sonora, Mexico, using data from satellite; Estimacion de evaporacion y radiacion solar en el valle del Yaqui, Sonora, usando datos de satelite

    Energy Technology Data Exchange (ETDEWEB)

    J Watts, Christopher; Rodriguez, Julio Cesar [Instituto del Medio Ambiente y el Desarrollo sustentable del estado de Sonora (Mexico); Garatuza Payan, Jaime [Instituto Tecnologico de Sonora (Mexico); Henk de Bruin [Universidad Agricola de Wageningen (Netherlands); Stewart, John [Universidad de Southampton (United Kingdom)

    1999-12-01

    The data from tow automatic weather stations in the Yaqui valley were used to estimate potential evaporation using the Makkink formula, based on observed incoming solar radiation and climatological values of air temperature. The usefulness of this formula was assessed by comparison with the Penman-Monteith, Penman and Priestley-Taylor formula and measurements of net radiation. A methodology was presented for estimating incoming solar radiation using visible band data from the GOES satellite. Comparisons against ground-based measurements from two pyranometers installed in the Yaqui valley gave good results, particularly in months with low cloud cover. Images for August 1993 were used to produce a map of the spatial distribution of potential evaporation. [Spanish] Para calcular la evaporacion potencial en el valle del Yaqui, usando la formula de Makkink, se utilizaron datos de dos estaciones meteorologicas automaticas. La mencionada formula se basa en la radiacion solar incidente observada y en ciertos valores climatologicos de temperatura del aire. Se evaluo la utilidad de esta formula, comparandola con las de Penman-Monteith, Pennan y Priestley-Taylor, asi como con mediciones de radiacion neta. Se desarrollo una metodologia para estimar la radiacion solar incidente usando la banda visible del satelite GOES. Se hizo una comparacion con mediciones de dos piranometros instalados en el valla del Yaqui, obteniendose buenos resultados, principalmente en meses con poca nubosidad. Se utilizaron imagenes de agosto de 1993 para producir un mapa de la distribucion espacial de la evaporacion potencial.

  11. Modification of residual stress in Al-[AlBO]w/Al compound plate

    Institute of Scientific and Technical Information of China (English)

    姜传海; 吴建生; 王德尊

    2001-01-01

    The application of compound parts of Al-[AlBO]w/Al not only reduces the cost of the parts but also improves its properties. However, there is a large thermal residual stress between Al and [AlBO]w/Al, and it is harmful for practical application. From the theoretical analyses and experimental results, it was found that by the compressive pre-plastic deformation perpendicular to the interface between Al and [AlBO]w/Al, the interlayer residual stress of compound parts can be reduced, while the mechanical properties of compound parts can be improved.

  12. Altern als Widerstand

    Directory of Open Access Journals (Sweden)

    Roberta Maierhofer

    2005-07-01

    Full Text Available Gullettes kulturwissenschaftliche Untersuchung Aged by Culture ist wie bereits ihre zwei vorangehenden Werke, die sich mit Altern beschäftigen – Safe at Last in the Middle Years: The Invention of the Midlife Progress Novel (1988 und Declining to Decline. Cultural Combat and the Politics of the Middle (1997 –, von großem persönlichen Engagement und durch ein politisches Anliegen motiviert. Sowohl die Dringlichkeit als auch der Widerstand, den Gullette, die sich als „age critic“ definiert, als moralische und politische Notwendigkeit postuliert, werden in der Zweiteilung der Abhandlung angesprochen: „Cultural Urgencies“ und „Theorizing Age Resistantly“. Während Gullette den Begriff „aged by culture“ bereits in Declining to Decline einführt, stellt sie ihn nun in den Mittelpunkt ihrer Untersuchung. Das Buch ist einerseits einer gesellschaftspolitischen Analyse der USA gewidmet, andererseits wird eine Theorie des Widerstands gegenüber Altersdiskriminierung entwickelt.

  13. Pornographie als Metapher

    Directory of Open Access Journals (Sweden)

    Caroline Schubarth

    2010-03-01

    Full Text Available In diesem Artikel werden unterschiedliche metaphorische Verwendungen des Pornografiebegriffs und deren Implikationen untersucht. Während die Existenz von Pornografie der feministischen Anti-Porno-Bewegung als Erklärung für die anhaltende Diskriminierung von Frauen in westlichen Gesellschaften dient, nutzen rechtskonservative Kräfte den Pornografievorwurf als Rechtfertigung für die Zensur von als deviant empfundenen Identitäten und sexuellen Praktiken.This article examines different metaphorical uses of the term pornography and the resulting implications. While the existence of pornography for the feminist anti-porno movement serves as factor in the continuing discrimination of women in western societies, conservative powers on the right use the allegation of pornography as a justification for censorship of those identities and sexual practices deemed deviant.

  14. Participation rates in the selection of population controls in a case-control study of colorectal cancer using two recruitment methods Tasas de participación en la selección de controles poblacionales en un estudio de casos y controles de cáncer colorrectal usando dos métodos de reclutamiento

    Directory of Open Access Journals (Sweden)

    Gemma Castaño-Vinyals

    2011-10-01

    Full Text Available Objectives: Low participation rates in the selection of population controls are an increasing concern for the validity of case-control studies worldwide. Methods: We conducted a pilot study to assess two approaches to recruiting population controls in a study of colorectal cancer, including a face-to-face interview and blood sample collection. In the first approach, persons identified through a population roster were invited to participate through a telephone call by an interviewer telephoning on behalf of our research center. In the second approach, individuals were identified from the lists of selected family practitioners and were telephoned on behalf of the family practitioner. Results: When the second method was used, participation rates increased from 42% to 57% and the percentage of refusals decreased from 47% to 13%. The reasons for refusing to participate did not differ significantly between the two methods. Conclusions: Contact through the family practitioner yielded higher response rates in population controls in the study area.Objetivos: Las bajas tasas de participación de controles poblacionales son una preocupación para la validez de los estudios de casos y controles. Métodos: Realizamos un estudio piloto utilizando dos estrategias de reclutamiento de controles poblacionales en un estudio de cáncer colorrectal, incluyendo una entrevista personal y una extracción de sangre. Con la primera estrategia, una entrevistadora llamaba en nombre del centro de investigación a los sujetos de un censo. Con la segunda estrategia, los sujetos fueron seleccionados a partir de los listados de población asignada a los médicos de familia y la llamada se hacía en nombre del médico. Resultados: Las tasas de participación aumentaron del 42% al 57% usando el segundo método; el porcentaje de rechazos disminuyó del 47% al 13%. Las razones de rechazo no diferían según la estrategia. Conclusiones: El contacto a través del médico de familia

  15. Wikipedia als Referenzorgan

    OpenAIRE

    Voß, Jakob

    2006-01-01

    Wikipedia wird inzwischen von vielen Nutzern regelmäßig als Nachschlagewerk genutzt. Aufgrund des offenen Charakters der Online-Enzyklopädie, bei der sich jeder direkt beteiligen kann, ist jedoch zusätzliche Medienkompetenz notwendig, um die Qualität einzelner Wikipedia-Artikel einschätzen zu können. Im Vortrag sollen Methoden zur Beurteilung von Wikipedia-Artikeln dargestellt und die Frage beleuchtet werden, unter welchen Umständen Wikipedia als Referenzorgan geeignet ist.

  16. Análisis sociocultural constructivista de las dificultades asociadas al estudio de temas geométricos en el nivel escolar: una alternativa metodológica usando recursos educativos abiertos

    OpenAIRE

    Ricaldi, Myrian

    2014-01-01

    La presente investigación se basa en el uso de la tecnología con bases teóricas socio-constructivistas y el enfoque teórico de Van Hiele para el análisis de tópicos de geometría. La pregunta de investigación planteada fue: ¿Cómo la aplicación de recursos educativos abiertos impacta en la comprensión de la geometría en estudiantes del nivel de educación secundaria? El diseño es cualitativo y se aplicó en un salón de clase de una institución privada de la ciudad de Lima. El estudio pretende con...

  17. BERKELEY: ALS ring

    International Nuclear Information System (INIS)

    Everybody at Lawrence Berkeley Laboratory's Center for Beam Physics is pleased with the rapid progress in commissioning LBL's Advanced Light Source (ALS) electron storage ring, the foundation for this third-generation synchrotron radiation facility. Designed for a maximum current of 400 mA, the ALS storage ring reached 407 mA just 24 days after storing the first beam on 16 March. ALS construction as a US Department of Energy (DOE) national user facility to provide high-brightness vacuum ultra-violet and soft x-ray radiation began in October 1987. One technical requirement marking project completion was to accumulate a 50-mA current in the storage ring. The ALS passed this milestone on 24 March, a week ahead of the official deadline. Once injected, the electron beam decays quasi-exponentially primarily because of interactions with residual gas molecules in the storage-ring vacuum chamber. Eventually, when the pressure in the vacuum chamber with beam decreases toward the expected operating level of 1 nano Torr, it will only be necessary to refill the storage ring at intervals of four to eight hours. At present the vacuum is improving rapidly as surfaces are irradiated (scrubbed) by the synchrotron radiation itself. At 100 mA, beam lifetime was about one hour (9 April)

  18. Al Shanker Remembers.

    Science.gov (United States)

    American Educator, 2000

    2000-01-01

    In a 1996 interview shortly before his death, Al Shanker, longtime president of the American Federation of Teachers, discussed such topics as: his own educational experiences; how he learned about political fighting in the Boy Scouts; the appeal of socialism; multinational corporations and the nation state; teaching tough students; and John Dewey…

  19. Modelado de Materiales Compuestos por Elementos Finitos usando Restricciones Cinemáticas Finite Element Modeling of Composite Materials using Kinematic Constraints

    Directory of Open Access Journals (Sweden)

    Oscar E. Ruiz

    2009-12-01

    Full Text Available El propósito de este artículo es presentar simulaciones del comportamiento de materiales compuestos basado en restricciones cinemáticas entre las mismas fibras y entre las fibras y la resina circundante. En la revisión de literatura, los autores han encontrado que las restricciones cinemáticas no han sido plenamente explotadas para modelar materiales compuestos, probablemente debido a su alto costo computacional. El propósito de este articulo es exponer la implementación y resultados de tal modelo, usando Análisis por Elementos Finitos de restricciones geométricas prescritas a los nodos de la resina y las fibras. Las descripciones analíticas del comportamiento de materiales compuestos raramente aparecen. Muchas aproximaciones para describir materiales compuestos en capas son basadas en la teoría de funciones C1Z y C0 Z, tal como la Teoría Clásica de Capas (CLT. Estas teorías de funciones contienen significativas simplificaciones del material, especialmente para compuestos tejidos. Una aproximación hibrida para modelar materiales compuestos con Elementos Finitos (FEA fue desarrollada por Sidhu y Averill y adaptada por Li y Sherwood para materiales compuestos tejidos con polipropileno de vidrio.The purpose of this article is to present simulations of the behavior of composite materials based on kinematic restrictions among the fibers themselves and among fibers and the surrounding resine. In the literature review the authors have found that the kinematic restrictions have not been fully exploited for modeling composite materials, probably due to their high computational expense. The purpose of this article is to show the implementation and results of such a model, by using a Finite Element Analysis of geometric restrictions prescribed to the resine and fiber nodes. Closed analytic descriptions on behavior of layered composite materials are very rare. Many approaches to describe layered composite material are based on the theory of

  20. Disfunção tireoidiana e conduta dos cardiologistas em pacientes usando amiodarona Thyroid dysfunction and cardiological management in patients receiving amiodarone

    Directory of Open Access Journals (Sweden)

    Anna Gabriela Fuks

    2004-06-01

    Full Text Available OBJETIVO: Determinar a prevalência de disfunção tireoidiana em pacientes usando amiodarona e os possíveis fatores associados. Verificar através de questionário aplicado a cardiologistas, a importância do fármaco causar alterações na função tireoidiana. MÉTODO: Avaliados 56 pacientes em uso crônico (> 3 meses de amiodarona com dosagens séricas de TSH, T4 livre, T3 total e Anti-TPO e definidos como portadores de disfunção tireoidiana (DT pacientes com TSH alterado. RESULTADOS: A prevalência de disfunção tireoidiana foi de 33,9%. Não houve diferença entre este grupo e os pacientes sem disfunção, exceto em relação à prevalência de anti-TPO positivo maior nos pacientes com DT (p=0,02. Hipotireoidismo subclínico foi diagnosticado em 10 (17,9% pacientes e hipotireoidismo clínico em 6 (10,7%. A prevalência de hipertireoidismo subclínico foi de 3,6% e de hipertireoidismo clínico de 1,8%. Anticorpos anti-TPO foram positivos em 5 (8% pacientes (dos quais 4 apresentavam disfunção. Quando comparados aos doentes sem anti-TPO positivo este grupo teve maior prevalência de disfunção (80% vs 29,4%; p=0,04. Verificado que apenas 49,2% dos cardiologistas faziam acompanhamento da função tireoidiana rotineiramente e a prevalência de disfunção referida na experiência da maioria era de 1 a 10%. CONCLUSÃO: A prevalência de disfunção tireoidiana na nossa população foi elevada, mostrando a necessidade de implementação de uma rotina laboratorial. Houve grande divergência entre os cardiologistas em relação ao tipo de acompanhamento utilizado nos pacientes em uso de amiodarona.OBJECTIVE: To determine the prevalence of thyroid dysfunction in patients receiving amiodarone, and the possible associated factors. The study also aimed at assessing the effect of amiodarone on thyroid function through the application of a questionnaire to cardiologists. METHOD: Fifty-six patients chronically (> 3 months receiving amiodarone were

  1. Estabelecimento de pastagem de capim-tanzânia usando milheto como cultura acompanhante The establishment of tanzania grass pasture using millet as a companion crop

    Directory of Open Access Journals (Sweden)

    Marcos Carvalho Maia

    2000-10-01

    Full Text Available Este estudo objetivou avaliar o rendimento e a composição química da forragem de milheto e de capim-tanzânia, a primeira espécie como cultura companheira, na formação de pastagem da gramínea perene Panicum maximum Jacq. cv. Tanzânia I, bem como a viabilidade do emprego desta prática. Os tratamentos avaliados foram quatro combinações de mistura de sementes, numa densidade de semeadura básica de 8 kg/ha, de capim-tanzânia/milheto: (08/00; 05/03; 04/04 e 03/05 kg/ha e três freqüências de corte (três cortes -- 40, 70 e 100 dias após a semeadura; dois cortes -- 50 e 100 dias após a semeadura; um corte -- 100 dias após a semeadura, no delineamento de blocos ao acaso, em esquema de parcelas subdivididas. As densidades de semeadura foram alocadas nas parcelas principais e as freqüências de cortes nas subparcelas. As produções de MS da associação entre milheto e capim-tanzânia foram maiores que as do capim-tanzânia exclusivo. A concentração de PB na MS de ambas as espécies aumentou, ao passo que os teores de FDN e FDA reduziram, com o aumento do número de cortes, porém, na consorciação, verificam-se valores semelhantes nos teores destas variáveis e pequena redução no teor de PB, quando comparados aos teores do capim-tanzânia exclusivo. Com base nestes resultados, conclui-se que é viável a formação de pastagem do capim-tanzânia usando o milheto como cultura acompanhante.The objective was to evaluate the forage yield and chemical composition of millet and Tanzania grass, the first one as a companion crop, in the formation of the Panicum maximum Jacq. cv. Tanzania I pasture, as well as the viability of the use of this practice. The evaluated treatments were four seed mixture combinations based on sowing density of 8 kg/ha of Tanzania grass/millet (08/00; 05/03; 04/04 and 03/05 kg/ha and three cutting frequencies (three cuttings - 40, 70 and 100 days after sowing, two cuttings - 50 and 100 days after sowing; one

  2. ALS insertion devices

    International Nuclear Information System (INIS)

    The Advanced Light Source (ALS), the first US third generation synchrotron radiation source, is currently under construction at the Lawrence Berkeley Laboratory. The low-emittance, 1.5 GeV electron storage ring and the insertion devices are specifically designed to produce high brightness beams in the UV to soft X-Ray range. The planned initial complement of insertion devices includes four 4.6 m long undulators, with period lengths of 3.9 cm, 5.0 cm (2) and 8.0 cm, and a 2.9 m long wiggler of 16 cm period length. Undulator design is well advanced and fabrication has begun on the 5.0 cm and 8.0 cm period length undulators. This paper discusses ALS insertion device requirements; general design philosophy; and design of the magnetic structure, support structure/drive systems, control system and vacuum system. 18 refs., 9 figs., 5 tabs

  3. De GPS al mapa

    Directory of Open Access Journals (Sweden)

    Esteban Dörries

    2016-03-01

    Full Text Available Las coordenadas Lambert obtenidas a partir de mediciones con equipos GPS de mano, llamados a veces navegadores, en ciertos casos confunden al usuario, por diferir claramente de su posición real al ser graficadas en un mapa del Instituto Geográfico Nacional (IGN: Esto puede resolverse con suficiente exactitud mediante una transformación de Molodensky, seguida de la correspondiente proyección cartográfica. Sin embargo, los tres parámetros necesarios para la transformación, supuestamente válidos para Costa Rica, se encuentran en muchas variantes y producen obviamente resultados diferentes. En este trabajo se analizan los fundamentos del problema y sus posibles soluciones, culminando con un estudio comparativo de ocho casos, que permite seleccionar los valores más adecuados para los parámetros.

  4. Acarbose als Carbophor

    OpenAIRE

    Merettig, Nadine

    2014-01-01

    Das Pseudotetrasaccharid Acarbose ist seit 1990 als kompetitiver Inhibitor intestinaler α-Glucosidasen (GlucobayTM/PrecoseTM) in der medizinischen Anwendung bei der Therapie von Diabetes mellitus Typ-2. Charakteristisch für die Struktur der Acarbose ist die Acarviosyleinheit, bei der Valinamin und Desoxyglucose N-glycosidisch verknüpft sind; des Weiteren ist an die Acarviosyleinheit ein Maltosylrest gebunden. Der Inhibitoreffekt beruht auf der irreversiblen Bindung zwischen ...

  5. Augmented Reality als Bildungsenhancement?

    OpenAIRE

    Damberger, Thomas

    2015-01-01

    Die Realität, die sich mithilfe von Datenbrillen und Smartphone Applikationen in die virtuelle Welt hinein ausdehnt, erfährt eine Form des Enhancements. Ein solches Enhancement kann unter bestimmten Voraussetzungen als Bildungsenhancement verstanden werden. Der Text befasst sich mit Formen der erweiterten Realität, ferner mit dem, um was es wesentlich bei der Bildung geht und zuletzt mit den Bedingungen, die erforderlich sind, um diesem Wesentlichen mit Hilfe von augmented reality besser zum ...

  6. Carta al editor

    OpenAIRE

    Harry Pachajoa

    2012-01-01

    Recently, Valencia et al., published a very interesting article called «Lipid profile in a group of patients with Turner’s syndrome at Clínica Universitaria Bolivariana in the city of Medellín between 2000 and 2009". An article which evaluated lipid levels in patients withTurner syndrome in a Colombian clinic, the study associated results of lipid profile with karyotype and other risk factors for coronary heart disease.

  7. Modelação da distribuição espacial da qualidade do ar em Lisboa usando sistemas de informação geográficas

    OpenAIRE

    Mesquita, Sandra Maria Pereira

    2010-01-01

    Com a presente dissertação pretendeu-se demonstrar a importância e potencialidade dos Sistemas de Informação Geográfica (SIG) na avaliação da poluição atmosférica. Usando ferramentas SIG, foram aplicadas e comparadas várias metodologias para modelar a distribuição espacial anual do poluente atmosférico dióxido de azoto (NO2) na cidade de Lisboa. Foram usados dados de NO2 da rede fixa de estações de monitorização de qualidade do ar e de duas campanhas com cerca de 100 tubos de d...

  8. Rastreamento da fibrose cística usando-se a análise combinada do teste de IRT neonatal e o estudo molecular da mutação DF508

    OpenAIRE

    Cabello Giselda M.K.; Cabello Pedro H; Roig Silvia R.S.; Fonseca Armando; Carvalho Eulália C.D.; Fernandes Octavio

    2003-01-01

    Um total de 117 cartões de rastreamento neonatal foi selecionado anonimamente para a avaliação de fibrose cística (FC) pela análise da mutação deltaF508 usando-se a técnica da reação em cadeia da polimerase (PCR), seguida de eletroforese em gel de poliacrilamida (Page) e pela quantificação da imunotripsina reativa (IRT, Delfia). Uma concentração de IRT menor que 140ng/ml foi encontrada em 116 recém-nascidos. Entre estes foi detectado um heterozigoto deltaF508 com uma concentração de IRT de 4,...

  9. Secagem do polissacarídeo λ-carragena usando um leito de jorro fluidizado bidimensional / drying of λ-carrageenan using a two dimensional spouted fluidized bed dryer

    OpenAIRE

    Ciro Velásquez, Héctor José; Menegalli, Florencia Cecilia; Lopes Da Cunha, Rosiane

    2012-01-01

    Resumo. Suspensões de λ-carragena foram secas usando um secador de leito de jorro fluidizado bidimensional com partículas inertesplásticas de ABS (acrilonitrilo-butadieno-estireno). O desempenho do secador (produção de pó e retenção de sólidos) e qualidade do produto seco obtido (propriedades reológicas e teor de umidade) foi avaliado. Os resultados mostraram que a eficiência de produção média de pó foi de 23% com uma retenção média de 71%. A variável mais relevante na secagem das suspensões ...

  10. Secagem do Polissacarídeo l-Carragena Usando um Leito de Jorro Fluidizado Bidimensional Drying of l-Carrageenan Using a Two Dimensional Spouted Fluidized Bed Dryer

    OpenAIRE

    Héctor José Ciro Velásquez; Florencia Cecilia Menegalli; Rosiane Lopes Da Cunha

    2012-01-01

    Resumo. Suspensões de l-carragena foram secas usando um secador de leito de jorro fluidizado bidimensional com partículas inertesplásticas de ABS (acrilonitrilo-butadieno-estireno). O desempenho do secador (produção de pó e retenção de sólidos) e qualidade do produto seco obtido (propriedades reológicas e teor de umidade) foi avaliado. Os resultados mostraram que a eficiência de produção média de pó foi de 23% com uma retenção média de 71%. A variável mais relevante na secagem das suspensões ...

  11. Proyección de emisiones vehiculares en Bogotá D.C., a 2050 usando como año base el año 2008

    OpenAIRE

    Guzmán Ramos, Luis Elkin

    2014-01-01

    El estudio muestra los resultados obtenidos de la proyección de emisiones vehiculares para la ciudad de Bogotá D.C., a 2050 usando como año base el año 2008. Para la realización del inventario se uso como software de apoyo el “Sistema de Planificación de Alternativas Energéticas de Largo Plazo” (LEAP); que es una herramienta para modelar escenarios energéticos y ambientales. Para alimentar el modelo se uso información energética de los consumos de combustible para la ciudad en el año base de ...

  12. Implantación y Parametrización del Subsitio Seguimiento y mejorarás usando la Tecnología de Windows Sharepoint Services

    OpenAIRE

    Chippirrás Andújar, Marta

    2010-01-01

    Proyecto Fin de Carrera leído en la Universidad Rey Juan Carlos en el curso académico 2009/2010. Tutor del Proyecto: Javier Martínez Moguerza En este proyecto se va a analizar y detallar el proceso de desarrollo e implantación del subsitio ¿Seguimiento y Mejoras¿, dentro del portal calidad construido Windows SharePoint Services. Orientado al soporte de sistemas de gestión de calidad que supone una alternativa al modelo tradicional de gestión. Su objetivo es simplificar la gestión de ...

  13. Um sistema de laje mista para edificações residenciais usando perfis de chapa dobrada com corrugações Composite slab system for residential constructions using cold-formed steel plates with embossments

    Directory of Open Access Journals (Sweden)

    Juliana Cruz Vianna

    2007-06-01

    Full Text Available Sistemas mistos aço-concreto têm sido largamente utilizados na construção civil e vêm motivando o desenvolvimento de sistemas de lajes de piso com forma de aço incorporado, usando-se perfis formados a frio com corrugações na alma. O sistema aqui investigado baseou-se em protótipos de fôrmas metálicas, usando várias formas de ligação na interface aço/concreto. Para desenvolver um novo perfil metálico, que apresentasse uma boa aderência mecânica entre o concreto e o aço e com comportamento dúctil, avaliou-se uma seção transversal ideal. Diversas variáveis foram consideradas, tais como: peso, altura, espessura e tensão de escoamento. A investigação, também, contemplou ensaios em escala real de forma a validar, experimentalmente, o sistema de laje mista (aço-concreto proposto.The composite steel-concrete system has been used in various major projects motivating the development of an efficient composite floor system using cold-formed steel sections with web corrugations. The system was based on previous investigations that involved the development of steel deck prototypes using various types of interlocking mechanisms in the concrete to steel deck interface. An ideal section evaluation was made to determine an efficient steel profile that presented a good mechanical adherence to the concrete interface while keeping a ductile behavior. Variables like weight, height, thickness and yield stress amongst others were investigated. An experimental program consisting of a full-scale composite slab test was executed to validate the proposed composite cold-formed system.

  14. Análisis de Tráfico Auto-similar en Redes de Comunicaciones Usando Onditas (Wavelets Analysis of Self-similar Traffic in Communication Networks using Wavelets

    Directory of Open Access Journals (Sweden)

    V. Alarcón-Aquino

    2005-01-01

    Full Text Available En este artículo se presenta un análisis de tráfico auto-similar (fractal en redes de comunicaciones usando onditas (wavelets. El objetivo del trabajo es mostrar la eficiencia del método basado en onditas para el análisis de procesos auto-similares, los cuales son caracterizados por estadísticas similares a diferentes escalas de tiempo. Se presenta un análisis comparativo de la estimación del parámetro de Hurst usando onditas tipo Daubechies en tráfico Ethernet e Internet. Los resultados muestran que el comportamiento del tráfico Ethernet es asintóticamente auto-similar y con dependencia en amplio rango, mientras que el tráfico Internet muestra aproximadamente un comportamiento con dependencia en corto rango. Estos resultados indican que los modelos de tráfico basados en una naturaleza auto-similar son más adecuados para modelar tráfico Ethernet, mientras que los modelos de Poisson pueden ser usados para modelar tráfico Internet.This paper presents an analysis of self-similar (fractal traffic in communication networks using wavelets. The aim of this work is to show the efficiency of the wavelet-based method for the analysis of self-similar processes, which posses similar statistical features over a long range of time scales. A comparative analysis of the estimated Hurst parameter using Daubechies wavelets in Ethernet and Internet traffic, are presented. The results reported in this paper show that the behavior of Ethernet traffic is asymptotically self-similar, while the Internet traffic shows behavior approximating short-range dependence. These results indicate that traffic models based on a self-similar nature are more suitable for modeling Ethernet traffic, while Poisson models may be used to model Internet traffic.

  15. MODELADO DEL PRECIO DEL CAFÉ COLOMBIANO EN LA BOLSA DE NUEVA YORK USANDO REDES NEURONALES ARTIFICIALES MODELLING OF THE COLOMBIAN COFFEE PRICE IN THE NEW YORK STOCK EXCHANGE USING ARTIFICIAL NEURAL NETWORKS

    Directory of Open Access Journals (Sweden)

    Juan David Velásquez Henao

    2007-12-01

    Full Text Available En este artículo, se modela el precio promedio mensual del café colombiano en la Bolsa de Nueva York, usando varios modelos alternativos. El modelo final seleccionado está compuesto por una componente lineal autorregresiva más una red neuronal artificial tipo perceptron multicapa con dos neuronas en la capa oculta, que permite representar la dinámica que sigue el valor esperado de la serie de precios; mientras que la dinámica de los residuales es especificada usando un proceso heterocedástico condicional autoregresivo de primer orden. Los residuales normalizados del modelo son incorrelacionados y homocedásticos, y siguen aproximadamente una distribución normal. Los resultados indican que el precio actual depende de los precios ocurridos en los últimos cuatro meses.In this paper, the monthly average price of the Colombian coffee in the New York Stock Exchange, is modelling by means of several alternative models. The preferred model is composed by a lineal autoregressive component plus a multilayer perceptron neural network with two neurons in the hidden layer, that allow us to representing the dynamic following by the expected value of the price time series; while, the dynamic of the residuals is specified by an autoregressive conditional heterocedastic model of first order. The normalized residuals of the preferred model are uncorrelated, homocedastic and are distributed following a normal distribution. The results indicate that the current price depend of the prices in the previous four months.

  16. Lesão brônquica e pneumotórax após reintubação usando um cateter para troca da via aérea Lesión brónquica y neumotórax posterior a la reintubación usando un catéter para el cambio de la vía aérea Bronchial injury and pneumothorax after reintubation using an airway exchange catheter

    OpenAIRE

    Almeida, Juliano P; Ludhmila A. Hajjar; Júlia T. Fukushima; Rosana E. Nakamura; Rodolfo Albertini; Filomena R.B.G. Galas

    2013-01-01

    JUSTIFICATIVA E OBJETIVOS: Relatamos um caso de pneumotórax causado por perfuração brônquica durante uma reintubação usando um cateter para troca da via aérea (CTVA) em um paciente com câncer de cabeça e pescoço. RELATO DE CASO: Paciente do sexo masculino, 53 anos, com carcinoma de orofaringe, foi internado na UTI com pneumonia grave e síndrome da angústia respiratória aguda (SARA). O paciente foi identificado como sendo de difícil intubação e uma sonda endotraqueal (SET) foi inserida através...

  17. FEEDER RECONFIGURATION AND CAPACITOR PLACEMENT IN DISTRIBUTION SYSTEMS: AN APPROACH FOR SIMULTANEOUS SOLUTION USING A GENETIC ALGORITHM RECONFIGURACIÓN Y UBICACIÓN DE CONDENSADORES EN SISTEMAS DE DISTRIBUCIÓN: METODOLOGÍA DE SOLUCIÓN SIMULTÁNEA USANDO ALGORITMOS GENÉTICOS

    Directory of Open Access Journals (Sweden)

    Horacio Díaz R

    2010-04-01

    Full Text Available This paper presents an effective approach to simultaneous solution of capacitor placement and feeder reconfiguration for power-energy loss cost minimization and voltage profile enhancement in radial distribution systems. Considering a time variation load, an optimization method using a genetic algorithm is proposed to determine the optimal location and size of fixed and switchable capacitors, as well as the open/closed states of the sectionalizing and tie switches. Reduction of overall power and energy losses and capacitor costs are involved in problem formulation. The proposed approach is demonstrated using example systems from the literature and results show that taken into account both capacitor placement and feeder reconfiguration simultaneously can generate around 10% more energy and peak loss reduction than considering them separately. Simulations results are presented for a 16 bus IEEE system and for a 733 bus practical distribution network.Este trabajo presenta una metodología para la solución simultánea de los problemas de ubicación de condensadores y reconfiguración de alimentadores en sistemas eléctricos de distribución radiales, con el fin de mejorar el perfil de voltaje de la red y, al mismo tiempo, reducir los costos asociados a las pérdidas de energía y potencia. Considerando un perfil de carga dado, se propone un método de optimización usando un algoritmo genético para determinar el tamaño óptimo, ubicación, tipo y número de condensadores fijos o conmutables, así como los estados abierto/cerrado de las llaves (switches seccionadoras y de interconexión. La formulación del problema considera la minimización de los costos totales, incluyendo costos fijos y variables de los bancos de condensadores. El método propuesto se ha probado en diversas redes y los resultados muestran que considerando ambos problemas simultáneamente los costos debidos a las pérdidas se pueden minimizar hasta un 10% más que tomando

  18. Aproximándose al “Link perdido”: pointing y lenguaje como intencionalidad compartida.

    Directory of Open Access Journals (Sweden)

    Ernesto E. Guerra

    2008-12-01

    Full Text Available Los humanos se comunican a través de un sistema distinto a otros seres vivos. Este artículo tiene como objetivo responder dos preguntas fundamentales sobre este sistema, el lenguaje humano; 1 ¿qué es lo que hace al lenguaje humano tan diferente de otras formas de comunicación? y 2 ¿qué nos ha llevado a desarrollar un sistema tan particular? Usando evidencia teórica y empírica, mostraremos como el lenguaje humano es único, ya que es una parte intrínseca de las habilidades cognitivas, y ya que la motivación comunicativa es fundamentalmente distinta a otras formas de comunicación entre seres vivos. Este sistema particular se ha desarrollado como el resultado de la aparición de habilidades cognitivo-sociales y de motivaciones sociales de comunicación, ambas manifiestas originalmente a través del acto de pointing (señalar, el cual aceptamos como un precursor del sistema de lenguaje humano más complejo. Esta proposición encuentra soporte tanto filo - como ontogenéticamente. Sobre el final, presentamos una hipótesis comprobable, sobre la evolución del lenguaje, basada en la intencionalidad compartida la cual de ser acertada daría aún mayor soporte a las ideas planteadas en este artículo.

  19. AL-USRCRN Station Information

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Documentation of United States Alabama Regional Climate Reference Network (AL-USRCRN) installations in 2006. Installations documented are for AL-USRCRN pilot...

  20. Derivados vinculados al seguro.

    Directory of Open Access Journals (Sweden)

    De Paz Cobo, Sonia

    2003-01-01

    Full Text Available El presente trabajo tiene como objetivo la presentación de los derivados financieros como instrumentos de cobertura de los riesgos del seguro, así como de los principales proyectos que se desarrollan a través de los mismos, como por ejemplo los derivados sobre el clima. Hay que tener presente las pérdidas multimillonarias ocasionadas en casos como el de la banca Baring’s, o el de Orange County, por citar algunas, que si bien ciertos autores afirman que están en relación directa con el uso de estos productos, no podemos olvidar que los instrumentos derivados se desarrollaron con el objetivo principal de proteger al usuario de la posible volatilidad del activo subyacente. Ya en la industria aseguradora los derivados vinculados a tal actividad son instrumentos donde el pago se condiciona a la ocurrencia de su suceso de siniestro, o serie de sucesos múltiples que disparen las pérdidas. Tras el repaso efectuado y la descripción que este tipo de instrumentos puede tener en la gestión del riesgo por parte de la industria aseguradora, concluiremos con la exposición de las relaciones con el reaseguro tradicional así como una breve referencia al futuro de este tipo de instrumentos

  1. Gliricidia sepium al establecimiento

    Directory of Open Access Journals (Sweden)

    J. L. Valle

    2004-01-01

    Full Text Available Se asoció Cenchrus ciliaris (Cc y Gliricidia sepium (Gs para evaluar la producción de biomasa y la composición química de los forrajes en la fase de establecimiento, en el estado de Morelos, México, en condiciones de trópico seco. Se empleó un análisis de varianza con diseño en bloques al azar, en donde T1 fue pasto solo, T2 Cc más Gs con 5,000 plantas ha-1 y el T3 Cs más Gs con 14,285 plantas ha-1. Se midió la producción de forraje individual y asociado con materia seca (t MS/Ha, la altura (A en cm, la proteína cruda (PC%, las fracciones de fibra (FDN% y FDA% y la digestibilidad in vitro de la materia seca (DIVMS%. El T3 tuvo una mejor producción de biomasa (P0.05. La asociación de 14,285 plantas ha-1 de G. sepium con pasto Cenchrus ciliaris mejoró la producción de biomasa y la disponibilidad total de nutrientes por superficie cultivada al establecimiento

  2. Utilidade do Ultrassom intracardíaco no isolamento de veias pulmonares usando cateter-balão a laser Utilidad del ultrasonido intracardíaco en el aislamiento de venas pulmonares usando catéter-balón láser Utility of intracardiac ultrasound imaging to guide pulmonary vein ablation using laser balloon catheter

    Directory of Open Access Journals (Sweden)

    Luiz Leite

    2009-12-01

    Full Text Available FUNDAMENTO: O isolamento das veias pulmonares (IVP tem sido usado como endpoint para a ablação da fibrilação atrial (FA com cateter balão. OBJETIVO: Determinar a utilidade do ultrassom intracardíaco (USIC para guiar o IVP, usando cateter balão a laser. MÉTODOS: 59 VP foram ablacionadas em 27 cães. Imagens de Doppler foram usadas para identificar os vazamentos do fluxo sanguíneo entre a VP e o balão. Após cada liberação de energia, o cateter de mapeamento circular foi reposicionado para verificar se o isolamento tinha sido obtido. A posição de vazamento foi então correlacionada com a posição do gap no estudo patológico. A análise de regressão logística multivariada foi realizada. RESULTADOS: Cinquenta e nove VP foram submetidas à ablação. O tempo médio de energia liberada foi de 279±177 seg., o diâmetro médio do balão era de 23±3 mm, e o comprimento médio do balão era 25±4 mm. O isolamento completo foi obtido em 38/59 (64%, e foi significantemente mais comum sem vazamento: [30/38 (79% versus 8/23 (35%, pFUNDAMENTO: Se usó el aislamiento de las venas pulmonares (AVP como endpoint para la ablación de la fibrilación atrial (FA con catéter-balón. OBJETIVO: Determinar la utilidad del ultrasonido intracardíaco (USIC para guiar el AVP, usando catéter-balón láser. MÉTODOS: Se ablacionaron 59 VP en 27 perros. Se usaron imágenes de Doppler para identificar los derrames del flujo sanguíneo entre la VP y el balón. Tras cada liberación de energía, se reposicionó el catéter de mapeamiento circular para verificar si se obtuvo el aislamiento. Se correlaccionó, entonces, la posición del derrame con la posición del gap en el estudio patológico. Se realizó el análisis de regresión logística multivariada. RESULTADOS: Se sometieron 59 VP a la ablación. El tiempo promedio de energía liberada fue de 279±177 seg., el diámetro promedio del balón era de 23±3 mm, y la largura promedio del balón era 25±4 mm

  3. Hydrogen-induced changes in the crystalline structure and mechanical properties of a Zn-Al eutectoid alloy rapidly solidified

    Energy Technology Data Exchange (ETDEWEB)

    Sandoval Jimenez, Alberto; Iturbe Garcia, Jose Luis [Instituto Nacional de Investigaciones Nucleares, Ocoyoacac, Estado de Mexico (Mexico)]. E-mail: alberto.sandoval@inin.gob.mx; asandovalj@correo.unam.mx; Negrete Sanchez, Jesus [Universidad Autonoma de San Luis Potosi, San Luis Potosi (Mexico); Torres Villasenor, Gabriel [Instituto de Investigaciones en Materiales, UNAM, Mexico D.F. (Mexico)

    2009-09-15

    Ribbon fractions of a zinc-aluminum eutectoid (Zn40.8Al%at.) alloy, obtained by rapid solidification using melt spinning technique, were submitted to a thermo-hydrogenation process by periods of 1, 6, 18, 24, 30, and 48 hours, to 200 degrees Celsius and 20 atmospheres. Thermo-hydrogenated samples were analyzed by transmission electron microscopy (TEM). Hydrogen-induced changes were produced, such as microstructure refining, development of crystalline defects, microhardness changes and modification of stable crystalline structures to {alpha}R meta-stable phase at room temperature. [Spanish] Fracciones de tiras de una aleacion eutectoide de zinc-aluminio (Zn40.8Al%at.), obtenidas mediante solidificacion rapida usando la tecnica de melt spinning, se sometieron a un proceso de termohidrogenacion por periodos de 1, 6, 18, 24, 30 y 48 horas, a 200 grados centigrados y 20 atmosferas. Las muestras termohidrogenadas se analizaron por microscopia electronica de transmision (MET). Se produjeron cambios inducidos por hidrogeno, tales como la refinacion de la microestructura, el desarrollo de defectos cristalinos, cambios de microdureza y modificacion de las estructuras cristalinas estables a fase metaestable {alpha}R a temperatura ambiente.

  4. Epitaxial growth of Al/Al2O3 multilayer structures

    International Nuclear Information System (INIS)

    In order to obtain Al-Al2O3 quantum effect devices, it is necessary to deposit epitaxially Al on Al2O3 and Al2O3 on Al. We have already obtained an epitaxial Al/Al2O3/Al structures on Si(111). In this paper, we have deposit Al/Al2O3/Al structures on Si(111), and investigated the crystallinity by using RBS. (author)

  5. Doppelthydrophile Blockcopolymere als Mineralisationstemplate

    Science.gov (United States)

    Kasparova, Pavla

    2002-07-01

    Die vorliegende Arbeit beschäftigt sich mit der Synthese und den Eigenschaften von doppelthydrophilen Blockcopolymeren und ihrer Anwendung in einem biomimetischen Mineralisationsprozeß von Calciumcarbonat und Bariumsulfat. Doppelthydrophile Blockcopolymere bestehen aus einem hydrophilen Block, der nicht mit Mineralien wechselwirkt und einem zweiten Polyelektrolyt-Block, der stark mit Mineraloberflächen wechselwirkt. Diese Blockcopolymere wurden durch ringöffnende Polymerisation von N-carboxyanhydriden (NCA's) und a-methoxy-ω-amino[poly(ethylene glycol)] PEG-NH2 als Initiator hergestellt. Die hergestellten Blockcopolymere wurden als effektive Wachstumsmodifikatoren für die Kristallisation von Calciumcarbonat und Bariumsulfat Mineralien eingesetzt. Die so erhaltenen Mineralpartikel (Kugeln, Hantel, eiförmige Partikel) wurden durch Lichtmikroskopie in Lösung, SEM und TEM charakterisiert. Röntgenweitwinkelstreuung (WAXS) wurde verwendet, um die Modifikation von Calciumcarbonat zu ermitteln und die Größe der Calciumcarbonat- und Bariumsulfat-Nanopartikel zu ermitteln. This work describes the synthesis and characterization of double hydrophilic block copolymers and their use in a biomimetic mineralization process of Calcium Carbonate and Barium Sulfate. Double hydrophilic block copolymers consist of a hydrophilic block that does not interact with minerals and another hydrophilic polyelectrolyte block that strongly interacts with mineral surfaces. These polymers were synthesised via ring opening polymerisation of N-carboxyanhydride (NCA), and the first hydrophilic block a-methoxy-ω-amino[poly(ethylene glycol)] PEG-NH2 was used as an initiator. The prepared block copolymers were used as effective crystal growth modifiers to control the crystallization of Calcium Carbonate and Barium Sulfate minerals. The resulting mineral particles (spheres, dumbbells, egg-like particles) were characterised by light microscopy in solution, by SEM, and by TEM. X-Ray scattering

  6. Fretting wear performances of multilayered PVD TiAlZrN/TiAlN/TiAl on AISI 4140 steel

    OpenAIRE

    Tlili, Brahim; NASRI, Mustapha; F. Ayari; Nouveau, Corinne

    2008-01-01

    Nowadays, most surface treatments are realized through vapor deposition techniques as thin hard coatings to guarantee; high surface hardness, low friction coefficient and improve wear resistance. Several experimental investigations have let to the development of a (TiAlCN/TiAlN/TiAl) and (TiAlZrN/TiAlN/TiAl) coatings in preference to the traditional TiN coating. In the current paper research conducted on fretting wear of a (TiAlCN/TiAlN/TiAl) and a (TiAlZrN/TiAlN/TiAl) multilayer coatings de...

  7. Desarrollo de un algoritmo de identificación de parámetros de líneas de transmisión y de la posición del cambiador de tomas (TAPS), usando técnicas de estimación de estado y mediciones fasoriales sincronizadas / Development of a parameter identification algorithm for transmission lines and tap changer position (TAPS), using state estimation techniques and synchronized phasor measurements

    OpenAIRE

    Borda Zapata, Carlos Eduardo

    2009-01-01

    Esta tesis presenta los resultados de un trabajo de investigación orientado a resolver el problema de obtener valores más exactos de los parámetros de la red de transmisión en un sistema de potencia. En este documento se describen varias metodologías de estimación de parámetros usando mediciones fasoriales sincronizadas obtenidas durante la operación. Se proponen varios algoritmos de estimación de parámetros para las líneas de transmisión y los transformadores, usando datos históricos de medi...

  8. Malamih al-Ashwat al-'Arabiyyah wa Makharijaha

    Directory of Open Access Journals (Sweden)

    Amrah Muhammad Kasim

    2015-12-01

    Full Text Available This writing discusses on al-ashwat al-‘arabiyyah that is known with “phonetic” term. It talks and interprets makharij al-huruf or place for producing sounds and also processing production of sounds by parts of mouth in Arabic language. The problems of sounds and its systems in Arabic language have been conducted by the scholars of al-ashwat al-‘arabiyyah attractively, neatly, and detail and gotten ahead the phonetic western scholars. Part of their analysis results formulate the study about al-ashwat al-sakinah (al-Shamit is known with vocal and consonant sounds in research questions shawait – shawamit. Ibnu Jinni has formulated “harakat”(wowel in Arabic language and dimension of letter  mad and liyn on alif  letter - waw - ya’ (ا و ي, from these letters create  harakat fathah, dammah, and kasrah. Moreover, in this writing also exist the description of hija’i letters and its makhraj that are correct from parts of mouth and the unity of coordinative sounds that produce sounds in morphemes arrangement, in one word that produces meaning. The result of phonological study has divided al-ashwat to be kinds of sound like the pronounced sounds, produced sounds from mouth, and heard sound.

  9. Efecto de la depuración en la biomasa del caracol Pomacea patula [Baker, 1922] usando el índice de condición

    Directory of Open Access Journals (Sweden)

    M. García-Ulloa

    2006-01-01

    Full Text Available La depuración de organismos acuáticos en cultivo es una práctica común. El tiempo de exposición de los animales al agua tratada es uno de los factores más importantes para su eficiencia, pudiendo afectar su biomasa. Se evaluó el efecto de la depuración en adultos de Pomacea patula mediante la aplicación del índice de condición (IC, bajo condiciones de laboratorio. Caracoles adultos obtenidos en cultivo se mantuvieron en peceras (Grupo 1 expuestos a un flujo de agua constante, tratada con radiación ultravioleta y limpieza diaria y en condiciones normales de mantenimiento (Grupo 2, con 5 réplicas por grupo. Se obtuvo el peso húmedo y longitud total individualmente, al inicio y después de una depuración de 10 días. El valor promedio del coeficiente de correlación (animales iniciales y de los Grupos 1 y 2 fue mayor a 0.90. El IC entre el valor inicial (771.81 ± 40.41 y los Grupos 1 y 2 (763.527 ± 25.24 y 765.465 ± 38.59, respectivamente, no mostró diferencias significativas (P > 0.05 al final del experimento. Los resultados sugieren que el proceso de depuración usado no afectó la biomasa de adultos de P. patula. El IC se mostró como una herramienta práctica de evaluación sin considerar la diferencia inicial de tallas de caracoles adultos

  10. Editorial: Cartas al Editor

    Directory of Open Access Journals (Sweden)

    Guillermo Llanos

    2006-06-01

    Full Text Available En todas las revistas biomédicas del mundo existe una sección habitual denominada como el título de este editorial y que en Colombia Médica la llamamos correspondencia. Este espacio tiene como objetivo fundamental que los lectores escriban a los autores (investigadores comentando los artículos que se han publicado en números anteriores de la revista. Las cartas son, entonces, breves comentarios de desacuerdo o acuerdo (conceptual, metodológico, interpretativo sobre falencias ubicadas por un lector alerta al tema debatido en cualquiera de las secciones como en los artículos originales, editoriales, revisiones, presentación de casos, etc. publicados previamente en la revista. Las cartas deben permitir el intercambio de opiniones y formas de pensar y analizar los problemas planteados entre los autores y los lectores. En ocasiones una serie de cartas motivadas por un artículo original puede ser tan o más interesante como el artículo que generó la correspondencia. Las cartas son también un formato adecuado para comunicar un hecho novedoso de una observación clínica juiciosa no descrita antes. Un ejemplo de ello es la carta de un gineco-obstetra australiano cuando informó a Lancet los primeros efectos adversos informados de la talidomida. Colombia Médica, a pesar de mantener vigente esta sección, no ha sido muy afortunada en establecer una buena cultura del envío de cartas al editor. Pero últimamente han llegado juiciosas observaciones a las cuales se les ha dado prioridad en su publicación. Toda carta que comenta los hallazgos de un artículo es enviada a los autores para su respuesta, porque ello genera el debate académico buscado, y luego se publican, tanto la carta como su respuesta. El Estilo Vancouver recomienda que la carta y su respuesta deban ser breve, no pasar de dos o tres párrafos y contener sólo cuatro o cinco referencias. En lo posible (a menos que sea indispensable no presentar ni cuadros ni gráficos. El t

  11. As tecnologias no contexto educativo : identificaçao e classificação dos resultados de aprendizagem usando a web semántica

    OpenAIRE

    Angélico Gonçalves, Maria José

    2014-01-01

    Los cambios en el Espacio Europeo de Enseñanza Superior (EEES) producidos por el proceso de Bolonia, asociados a modificaciones pedagógicas y metodológicas, han originado un nuevo paradigma enseñanza/aprendizaje. Las Tecnologías de la Información asumen, por tanto, uma creciente relevancia, al plantear nuevos desafíos y modelos a la educación. Por ello, la existencia de información en la Web Semántica (WS) sobre las Unidades Curriculares (UC) y sus respectivas Competencias y Resultados del...

  12. Implementación de un amplificador sincrónico digital (Lock-in) usando un dispositivo FPGA (Field Programmable Gate Array)

    OpenAIRE

    Cifuentes Castro, Ángel Sergio

    2014-01-01

    El contar con la capacidad de distinguir entre señales útiles y ruido es un problema común en los laboratorios científicos. Algunos fenómenos físicos, como por ejemplo los fenómenos fototérmicos, generan señales de muy baja intensidad al ser estudiados. Estas señales pueden perderse fácilmente entre ruido de diversas fuentes, como por ejemplo el ruido térmico. Un amplificador sincrónico digital (LIA por sus siglas en inglés) es un instrumento capaz de proveer una alta selectividad de frecuenc...

  13. Eliminación de microorganismos patógenos en aguas mediante filtración usando complejos polímeros-minerales de arcilla.

    OpenAIRE

    Undabeytia López, Tomás; Posada, R.; Nir, Shlomo; Galindo, I.; Laiz Trobajo, L.; Sáiz-Jiménez, Cesáreo; Morillo González, Esmeralda

    2014-01-01

    Los procesos de desinfección son cruciales en servicios de tratamientos de agua. La desinfección se realiza tradicionalmente en plantas de tratamiento de aguas mediante cloración, que reduce enormemente los patógenos presentes en el agua, pero puede presentar un serio riesgo para la salud humana por la formación de bioproductos de desinfección. Los procesos de desinfección mejoran enormemente al combinarlos con otros procesos de tratamiento. La filtración en lecho se encuentra incorporada en ...

  14. Compensación de corriente usando filtro activo de potencia en derivación para fuentes armónicas de tensión

    OpenAIRE

    Trujillo Orozco, Odair Augusto

    2015-01-01

    El presente documento muestra los resultados de investigación sobre la compensación de problemas de calidad de la potencia, específicamente los problemas de distorsión armónica en las redes de distribución de energía a nivel industrial. Se introduce al lector a los problemas de la calidad de la potencia, para posteriormente acotar el tema a los armónicos en la corriente y la tensión, sus fuentes de generación y la compensación o filtrado de los mismos. Los problemas de calidad de la potenc...

  15. Determinación de parámetros cosmológicos usando oscilaciones acústicas de bariones en cartografiados fotométricos de galaxias

    OpenAIRE

    Carnero Rosell, Aurelio

    2011-01-01

    El descubrimiento de la materia oscura y la energía oscura en el siglo XX ha supuesto una revolución para la cosmología y nos ha permitido entender que la contribución de las estrellas y los planetas al contenido energético del Universo es despreciable. La naturaleza de estas dos componentes es completamente desconocida y entenderla es uno de los interrogantes más importantes a los que se enfrenta la física a principios del siglo XXI. Las principales técnicas de estudio de la energía oscura s...

  16. Modelo híbrido para el control inteligente de procesos, usando tecnología de conjuntos difusos, redes neuronales o artificiales y sistemas basados en conocimientos

    OpenAIRE

    ÁLVAREZ ZAPATA, HERNÁN DARÍO

    1995-01-01

    Resumen: En el presente trabajo, se muestra una visión global de lo que es el control de procesos, para, posteriormente, concentrar toda la atención en el control asistido por computador y más concretamente en la aplicación de técnicas de inteligencia artificial al control de procesos. Las redes neuronales artificiales (RNA), los sistemas basados en conocimientos (SBCS) y la lógica difusa (LD), tres técnicas de inteligencia artificial, se estudian en detalle con el fin de detectar sus fortale...

  17. Diseño y construcción de un micro-robot usando tarjetas Arduino y una impresora 3D

    OpenAIRE

    Mate Martínez, Ángel

    2013-01-01

    El principal objetivo de este trabajo de fin de grado es la construcción de varios micro-robots como plataforma para la docencia. Este trabajo constara de dos partes una mecánica y otra electrónica. En cuanto a la mecánica diseñaremos el robot basándonos en el skybot. Para fabricar las piezas diseñadas se empleara una impresora 3D. En cuanto a la electrónica se emplearan varios tipos de sensores para aportar al robot una mayor flexibilidad. Se diseñara una shield impresa para la placa a...

  18. Escalado de un proceso de biooxidación de residuos de minería ricos en sulfuros usando reactores de tanque agitado

    OpenAIRE

    MUÑOZ ECHEVERRI, LAURA MARÍA

    2015-01-01

    Resumen: En este trabajo se presenta el escalado y evaluación del proceso de biooxidación de un residuo de minería aurífera (proveniente de la mina La Maruja, Marmato-Caldas), desde una escala de laboratorio hasta un nivel de planta piloto en reactores de tanque agitado. Para procurar el éxito del escalado, se realizó una caracterización mineralógica inicial del residuo y una adaptación del agente biológico, Acidithiobacillus ferrooxidans, al mineral. A escala de laboratorio se determinó el n...

  19. Predicción de la cristalización de la tripalmitina en la trioleina usando como herramienta redes neuronales artificiales

    OpenAIRE

    Morales Castro, Juliana; González-Laredo, Rubén F.; Rocha Guzmán, Nuria E.; Rico-Martínez, Ramiro; Gallegos-Infante, José-Alberto

    2003-01-01

    The use of classical theories in lipid crystallization (i.e. Avrami model), give only a partial fit of the experimental data. This fact was explained because its was shown a drastic drop in the values of the interfacial free energy of the blends, but in the tripalmitin pure not. An alternative to the modeling to this type of systems was demonstrated with a one type of ANN. It compares the predictions of the ANN Vs the predictions of the Avrami model. The predictions of the ANN were good in al...

  20. ¿Por qué enseñar a escribir usando técnicas de "Focus on Form"?

    OpenAIRE

    Rosa Mª Lucha Cuadros

    2006-01-01

    El estudio que aquí presentamos aborda los siguientes temas: 1. Indaga acerca de si una enseñanza intensiva centrada en la forma induce o no a obtener resultados más positivos en la adquisición, al menos en la memoria a corto plazo, de estructuras lingüísticas significativas; en nuestro caso estructuras para comparar y expresar ventajas e inconvenientes. 2. Permite postular la efectividad del uso de herramientas informáticas para evaluar la “calidad de información” (Díaz y Ruggia 2004) de...

  1. Variabilidad genética de Aedes aegypti en algunas áreas del Perú usando Single Stranded Conformational Polymorphism (SSCP)

    OpenAIRE

    Nélida Leiva G; Omar Cáceres R

    2004-01-01

    Aedes aegypti es el vector responsable de la transmisión del virus del dengue, su distribución geográfica se ha ampliado rápidamente debido principalmente a la intervención de los seres humanos. Objetivo: Analizar la variabilidad genética de este mosquito mediante la comparación del Segundo Espaciador Transcrito Interno (ITS 2) perteneciente al ADN ribosomal (rADN). Materiales y Métodos: Se analizaron muestras de ocho localidades (Jaén, Tingo María, Iquitos, Lambayeque, el distrito de El Rima...

  2. Ocultamiento del Mensaje de Señales de Voz usando la Transformada de Ondita Haar Discreta Message Concealment of Voice Signals using the Discrete Haar Wavelet Transform

    Directory of Open Access Journals (Sweden)

    Alejandro Martínez

    2010-01-01

    Full Text Available Este trabajo presenta un método de ocultamiento del mensaje para transmisión de señales de voz utilizando codificación por medio de bancos de filtros multi-resolución de análisis y de síntesis para la Transformada de Ondita Haar Discreta. Por medio de un banco de filtros Haar multi-resolución se realiza la separación de la señal en sus componentes y después se realiza una distorsión reversible de la síntesis multi-resolución de sus señales componentes, obteniendo una señal de salida que, aunque mantiene la misma información de la señal de entrada, el mensaje de la señal de voz que esta porta queda oculto en ella misma. Este método puede aplicarse para la transmisión codificada de señales de voz ya sea en su forma digital o analógica, y por su simplicidad resulta adecuado para implementarse en sistemas electrónicos digitales, ya sea como un arreglo de compuertas programables por campo, o como circuito integrado de aplicación específica.This work introduces a message concealment method for voice signals transmission using codification through multi-resolution filter banks implementation for analysis and synthesis for the Discrete Haar Wavelet Transform. Through these multi-resolution filter banks of Haar wavelet the voice signal can be split in its components, and later a reversible distortion of the synthesis of its multi-resolution component signals is made, obtaining an output signal that, although maintains the same information of the original input signal, hides the message of the carried voice signal in itself. This method can be applied in codified transmission of voice, analog or digital signals, and due to the simplicity of the method it’s suitable to be implemented on digital electronic systems like FPGA, or ASIC.

  3. Determinação de umidade em café cru usando espectroscopia NIR e regressão multivariada Determination of moisture in raw coffee by near infra-red reflectance spectroscopy and multivariate regression

    Directory of Open Access Journals (Sweden)

    Marcelo Antonio Morgano

    2008-03-01

    Full Text Available A espectroscopia na região do infravermelho próximo (NIR foi usada para determinar o teor de umidade em amostras de café cru. Foram construídos modelos de regressão usando o método dos mínimos quadrados parciais (PLS com diferentes pré-tratamentos de dados e 157 espectros NIR coletados de amostras de café usando um acessório de reflectância difusa, na região entre 4500 e 10000 cm-1. Os espectros originais passaram por diferentes transformações e pré-tratamentos matemáticos, como a transformação Kubelka-Munk; a correção multiplicativa de sinal (MSC; o alisamento com SPLINE e a média móvel, e os dados foram escalados pela variância. O modelo de regressão permitiu determinar o teor de umidade nas amostras de café cru com erro quadrático médio de calibração (SEC de 0,569 g.100 g -1; erro quadrático médio de validação de 0,298 g.100 g -1; coeficiente de correlação (r 0,712 e 0,818 para calibração e validação, respectivamente; e erro relativo médio de 4,1% para amostras de validação.Near infra-red reflectance (NIR spectroscopy was used to measure the moisture content in raw coffee. Different models using partial least squares (PLS with data pre-processing were used. Regression models were built with 157 spectra of the samples of raw coffee collected using a near infrared spectrometer with an accessory of diffuse reflectance, between 4500 and 10000 cm-1. The original NIR spectra went through different transformations and mathematical pre treatments, such as the Kubelka-Munk transformation; multiplicative signal correction (MSC; spline smoothing and movable average, and the data were scaled by variance. The regression model permitted the determination of the moisture content of the raw coffee samples with a standard error of calibration (SEC = 0.569 g.100 g -1; standard error of validation = 0.298 g.100 g -1; correlation coefficient (r 0.712 and 0.818 for calibration and validation, respectively, and average

  4. Determinación simultanea de seis analgésicos en plasma humano usando extracción en fase sólida y cromatografía liquida

    Directory of Open Access Journals (Sweden)

    P. Fernández

    2012-01-01

    Full Text Available Se desarrolló un método analítico para la determinación simultánea de paracetamol, ácido salicílico, metamizol, tramadol, ibuprofeno y diclofenaco en plasma, usando Cromatografía Líquida de Alta Resolución acoplada a un detector de array de diodos (HPLC-PDA. Se realizó una extracción en fase sólida (SPE con cartuchos Oasis HLB® . Después de acondicionar los cartuchos con acetato de etilo, metanol y tampón fosfato pH 4, e introducir la muestra de plasma, los analitos fueron eluídos con acetato de etilo; el extracto se evaporó a sequedad, se redisolvió en fase móvil y se inyectaron 30 μLen el cromatógrafo. La separación cromatográfica fue realizada TM usando una columna XBridge Shield RP18 (250x4.6 mm id, 5 μm tamaño partícula, y la elución se hizo con una fase móvil, compuesta por acetonitrilo, tampón fosfato pH 6,0 y agua Milli-Q, a un flujo de 1 mL/min, en modo gradiente. La respuesta del detector es lineal en el rango 0,1-20 μg/mL en plasma, con coeficientes de correlación mayores de 0.997. Los límites de detección variaron desde 7,3 a 30,1 ng/mL. Los coeficientes de variación fueron menores de 8%, y las recuperaciones oscilaron entre 90,1% para diclofenaco y 100,2% para ácido salicílico. Finalmente, se aplicó el método a 16 muestras de plasma procedentes de sujetos intoxicados con uno o más analgésicos.

  5. Evaluation of Top-Cross Popcorn Hybrids Using Mixed Linear Model Methodology Evaluación de Híbridos Top-Cross de Maíz-Roseta Usando Modelos Lineales Mixtos

    Directory of Open Access Journals (Sweden)

    Emmanuel Arnhold

    2009-03-01

    Full Text Available The market for popcorn (Zea mays L. has been continuously growing in Brazil fact has required the development of cultivars adapted to local environmental conditions. For this reason, the analytical objectives of this study were to evaluate top-cross popcorn hybrids in relation to popping expansion and grain yield in three different eco-geographic regions of Brazil, in order to estimate variance components using Restricted Maximum Likelihood (REML and predict breeding values using Best Linear Unbiased Prediction (BLUP. Genetic evaluation considered a linear model with heterogeneous residual (environmental variances. The Restricted Likelihood Ratio Test (RLRT evidenced significant differences (p Evaluación de híbridos top-cross de maíz-roseta usando modelos lineales mixtos. El mercado del maíz-roseta (Zea mays L. está en continuo crecimiento en Brasil, lo cual ha demandado el desarrollo de cultivares adaptados a las condiciones locales. Por ello, los objetivos del presente trabajo fueron evaluar híbridos top-cross de maíz-roseta en función de la capacidad de expansión y el rendimiento de los granos, en diferentes regiones eco-geográficas de Brasil; estimar componentes de varianza usando Máxima Verosimilitud Restringida (REML y predecir los valores genotípicos a través de la Mejor Predicción Linear Insesgada (BLUP. La evaluación genética consideró un modelo lineal con una estructura de varianza residual (ambiental heterogénea. La prueba de la razón de verosimilitud (restringida evidenció diferencias significativas (p < 0,01 para el efecto genotípico. La producción de granos mostró ser una característica de heredabilidad media (h² = 0,26-0,39. En la capacidad de expansión se evidenció un mayor control genético aditivo (h² = 0,58-0,85. Las correlaciones genéticas y de Spearman entre las características fueron negativas, indicando que la selección basada en el rendimiento de granos tendría un efecto negativo sobre la

  6. Análisis mecánico y tribológico de los recubrimientos fe-cr-ni-c y ni-al-mo

    Directory of Open Access Journals (Sweden)

    JORGE E. MUÑOZ

    2007-01-01

    Full Text Available En este trabajo de investigación se evaluaron dos recubrimientos aplicados por medio de la técnica de rociado térmico por combustión, la aleación: Ni=89%, Al = 5,5%, Mo=5,5% y la aleación Fe=81,8%, Cr=16%, Ni=2%, C=0,2. La preparación superficial de las probetas se realizó usando chorro de arena. Se realizaron pruebas de resistencia al cortante, adherencia, desgaste abrasivo, desgaste por deslizamiento y flexión en cuatro puntos. El recubrimiento Fe-Cr-Ni-C presentó menor pérdida de masa, tanto para desgaste abrasivo como para el desgaste por deslizamiento. La multicapa presentó una mayor porosidad en el recubrimiento Ni-Al- Mo usado como capa base y la capa exterior de Fe-Cr-Ni-C presentó mayor cantidad de partículas no fundidas y óxidos. La falla ocurrida en el ensayo de adherencia para las probetas con recubrimiento multicapa fue de característica adhesiva y cohesiva. El esfuerzo en el que se presenta la fisura por flexión en el recubrimiento multicapa disminuyó con el aumento del espesor

  7. A estrutura de capital das maiores empresas brasileiras: análise empírica das teorias de pecking order e trade-off, usando panel data.

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Correa

    2013-08-01

    Full Text Available Pesquisas sobre estrutura de capital das empresas são consideradas dentre as mais relevantes na área de finanças. Diversas abordagens teóricas têm sido discutidas e testadas na literatura financeira. Este estudo buscou analisar o nível de endividamento das maiores empresas brasileiras, à luz das duas principais teorias que versam sobre o assunto, a teoria de Pecking Order e a teoria de trade--off, testando seus determinantes. A teoria do Pecking Order sugere a existência de uma hierarquia no uso de fontes de recursos, enquanto a teoria de trade-off considera a existência de uma estrutura meta de capital que seria perseguida pela empresa. O estudo é uma adaptação do artigo de Gaud et al. (2005, cujo trabalho serviu como base e principal referência para a escolha das principais variáveis e dos testes econométricos realizados. Tal como Gaud et al. (2005, desenvolvemos as análises estatísticas utilizando a metodologia de Panel Data, que considera os dados da amostra em corte transversal e longitudinal. Além de testes estáticos, foram feitos testes dinâmicos, com o objetivo de analisar o processo de ajuste da estrutura de capital ao longo do tempo, em direção a um suposto nível-alvo ótimo. Os resultados demonstraram relação negativa entre o nível de endividamento das empresas e o grau de tangibilidade dos ativos e a rentabilidade, bem como relação positiva do endividamento com o risco. Demonstraram ainda que empresas de capital estrangeiro são mais endividadas que empresas nacionais. De um modo geral, os resultados sugerem que a teoria de Pecking Order é mais consistente do que a teoria de trade-off para explicar a estrutura de capital das companhias abertas brasileiras. Em especial, destacamos a relação negativa entre endividamento e rentabilidade, confirmando vários outros resultados de pesquisa obtidos na realidade brasileira. A análise dinâmica demonstrou baixa velocidade do processo de ajuste da estrutura de

  8. Alexandria (Al Iskandariya), Egypt

    Science.gov (United States)

    2002-01-01

    This image of Alexandria was taken by astronauts on board the International Space Station in December 2000 using an Electronic Still Camera. A wider-angle view (STS088-739-90) taken from the Space Shuttle in December 1998 is available for context. Alexandria (Al Iskandariya) occupies a T-shaped peninsula and strip of land separating the Mediterranean from Lake Mariout. Originally the town was built upon a mole (stone breakwater) called Heptastadium, which joined the island of Pharos (see referenced website, below) to the mainland. Since then sedimentary deposits have widened the mole. Since 1905, when the 370,000 Alexandrians lived in an area of about 4 sq km between the two harbors, the city (population 4 million; see referenced website, below) has grown beyond its medieval walls and now occupies an area of about 300 sq km. The Mahmudiya Canal, connecting Alexandria with the Nile, runs to the south of the city and, by a series of locks, enters the harbor of the principal port of Egypt (note ships). The reddish and ochre polygons west of Lake Mariout are salt-evaporation, chemical-storage, and water-treatment ponds within the coastal lagoon. Reference Youssef Halim and Fatma Abou Shouk, 2000, Human impacts on Alexandria's marine environment: UNESCO, Coastal Regions and Small Islands Unit (CSI), Coastal Management Sourcebooks 2 (accessed December 20, 2000) Additional photographs taken by astronauts can be viewed at NASA-JSC's Gateway to Astronaut Photography of Earth. Image ISS001-ESC-5025 provided by the Earth Sciences and Image Analysis Laboratory, Johnson Space Center.

  9. Undulators at the ALS

    International Nuclear Information System (INIS)

    At Lawrence Berkeley Laboratory's (LBL) Advanced Light Source (ALS), three 4.6 m long undulators have been completed, tested and installed. A fourth is under construction. The completed undulators include two 5.0 cm period length, 89 period devices (U5.0s) which achieve a 0.85 T effective field at a 14 mm minimum gap and a 8.0 cm period length, 55 period device (U8.0) that reaches a 1.2 T effective field at a 14 mm minimum gap. The undulator under construction is a 10.0 cm period length, 43 period device (U10.0) that is designed to achieve 0.98 T at a 23 mm gap. Undulator magnetic gap variation (rms) is within 25 microns over the periodic structure length. Reproducibility of the adjustable magnetic gap has been measured to be within +/- 5 microns. Gap adjusting range is from 14 mm to 210 mm, which can be scanned in one minute. The 5.1 m long vacuum chambers are flat in the vertical direction to within 0.74 mm and straight in the horizontal direction to within 0.08 mm over the 4.6 m magnetic structure sections. Vacuum chamber base pressures after UHV beam conditioning are. in the mid 10-11 Torr range and storage ring operating pressures with full current are in the low 10-10 Torr range. Measurements show that the uncorrelated magnetic field errors are 0.23%, and 0.20% for the two U5.Os and the U8.0 respectively and that the field integrals are small over the 1 cm by 6 cm beam aperture. Device description, fabrication, and measurements are presented

  10. Variación del índice de niebla usando un corpus obtenido a partir de los libros digitalizados por google

    OpenAIRE

    Felipe Ovares Barquero; José Alberto Rubí Barquero

    2016-01-01

    En lingüística, principalmente en el idioma inglés, se usa el Índice de Niebla de Gunning para determinar la legibilidad de un texto. El índice estima los años de educación formal necesarios para comprender el texto en una primera lectura. Un Índice de 11 años apunta a una persona con el colegio finalizado, (Gunning, 1973). Analizamos en esta investigación la variación del Índice al cambiar la forma de obtener uno de los parámetros. En la fórmula original se consideran “palabras complejas”...

  11. Predicción de la cristalización de la tripalmitina en la trioleina usando como herramienta redes neuronales artificiales

    Directory of Open Access Journals (Sweden)

    Morales Castro, Juliana

    2003-09-01

    Full Text Available The use of classical theories in lipid crystallization (i.e. Avrami model, give only a partial fit of the experimental data. This fact was explained because its was shown a drastic drop in the values of the interfacial free energy of the blends, but in the tripalmitin pure not. An alternative to the modeling to this type of systems was demonstrated with a one type of ANN. It compares the predictions of the ANN Vs the predictions of the Avrami model. The predictions of the ANN were good in all cases in the levels of cooling was low, but Avrami cannot fit the experimental data. The analysis of the ANN shown the possibility of the presence of two mechanism of crystallization associated to the cooling.El uso de teorías estándar en cristalización de lípidos, por ejemplo el modelo de Avrami, proporcionan solo un ajuste parcial con los datos experimentales obtenidos. Lo cual fue explicado por una drástica caída en la energía libre interfacial en las mezclas a diferencia del sistema puro. Una alternativa al modelado de este tipo de sistemas, fue demostrada mediante el uso de un tipo de red neuronal artificial. Comparando las predicciones de esta con aquellas obtenidas por el modelo de Avrami. Encontrando que la red neuronal artificial era exitosa en todos los casos en donde no se tenia un nivel elevado de enfriamiento, en tanto que el modelo de Avrami fallaba en reproducir los resultados experimentales. Los resultados del análisis de la red neuronal artificial, mostraron la posible existencia de dos diferentes mecanismos de cristalización, asociados al nivel de enfriamiento.

  12. Epistemologi Sufi : Perspektif Al-Hakim Al-Tirmidzi

    Directory of Open Access Journals (Sweden)

    Ainul Abidin Shah

    2012-06-01

    Full Text Available Abstract : This article deals with some epistemological terms and theoretical postulates in the thought of a well known sufi  from the 9th century AD., Abu `Abdu’lLah Muhammad b. `Ali al-Hakim al-Tirmidzi, in order to describe the path (sulūk of a sufi towards the Ultimate Reality. In his own style thought about the sufis, placing an emphasis upon the strong relations between the walāyah (sufi  sainthood and the ma`rifa (sufi knowledge in the one side, and between the two a philosophy of Sufi Ethics. So, it is nothing out of the ordinary to fi nd his ethical inclinations as a dominant feature in every aspect of his epistemological thoughts. In addition, sufi epistemology in the perspective of philosophers focuses on enforcing the inner positive potents of the Self more so than to eliminate “the satanic influences” to the heart, because – in al-Tirmidzi’s argument is that the former would greatly improve the immunity of the self, and encourage it to tread consistently on the right path as well.Keywords :  Dhawq, eros, heart, exoteric, esoteric, al-Haqq, al-`Adl, al-Shidq Abstrak : Artikel ini membahas istilah-istilah epistemologi dan beberapa postulat dari seorang sufi terkenal abad ke-9, Abu `Abdu’lLahMuh ammad b.`Ali al-Hakim al-Tirmidzi, dalam upaya menggambarkan perjalanan suluk seorang sufi menuju Realitas Mutlak. Dalam gaya pemikirannya tentang sufi, kita menemukan bahwa figur ini cenderung  menekankan hubungan-hubungan yang kuat antara wal āyah (kewalian sufi dan ma‘rifa (pengetahuan sufi di satu sisi, dan antara keduanya dengan filsafat moral sufi.  Jadi, tidak aneh jika kita menemukan kecenderungan - kecenderungan etis yang dominan dalam setiap aspek  pemikiran epistemologinya. Dan epistemologi sufi dalam perspektif para filsuf lebih menekankan potensi inner Diri yang positif daripada menghapuskan “cara-cara syaitan” dalam hati, karena - menurut pendapat al-Tirmidzi – ia akan meningkatkan

  13. Comparação das técnicas transarterial e de estimulação de múltiplos nervos para bloqueio do plexo braquial por via axilar usando lidocaína com epinefrina Comparación de las técnicas transarterial y de estimulación de múltiples nervios para bloqueo del plexo braquial por vía axilar usando lidocaína con epinefrina Comparison of transarterial and multiple nerve stimulation techniques for axillary block using lidocaine with epinephrine

    OpenAIRE

    Luiz Eduardo Imbelloni; Lúcia Beato; José Antônio Cordeiro

    2005-01-01

    JUSTIFICATIVA E OBJETIVOS: A técnica transarterial com grandes doses de anestésico local resulta em alta efetividade para o bloqueio axilar do plexo braquial. A técnica utilizando múltiplos estímulos exige mais tempo e maior experiência. Este estudo prospectivo compara a latência e o índice de sucesso do bloqueio do plexo braquial usando duas técnicas de localização: transarterial ou múltipla estimulação dos nervos. MÉTODO: A lidocaína com epinefrina, 800 mg, foi usada inicialmente para o blo...

  14. Al2O3 sintered pellets as thermoluminescent dosimeters Pastillas sinterizadas de Al2O3 como dosímetros termoluminiscentes

    Directory of Open Access Journals (Sweden)

    Amalia Osorio

    2012-06-01

    Full Text Available Verification of the radiation doses received by the area exposed during medical treatment is essential for assessing any scheme radiotherapy. This workdescribes the characteristic thermoluminescent (TL of sintered Al2O3 pellets, for its use as dosimeter dose low. Sintered Al2O3 pellets under different calcinations with a diameter of 5 mm and a thickness of 1 mm, they were irradiated to different dose using an unit of60 Co Theratron 780Cr in air to ambient temperature. The reading was carried in a Harshaw TLD 4500. Themain dosimetric properties of the material (glow curve, response reproducibility, reutilization, linearity and fading have been studied in detail. The glowcurve of the thin sintered Al2O3 pellets presents an intense peak TL to about 165◦C, which can be used for dosimetry. The results show that the pellets canbe used in quality control programs as thermoluminescent dosimeter in therapeutic dose range. The importance of this work is that the aluminum oxide (α−Al2O3 is a promising alternative in TL materials used for dosimetry “in vivo” within quality control programs.La verificación de la dosis de radiación recibida por el área expuesta durante eltratamiento médico es esencial para la evaluación de cualquier régimen de radioterapia.Este trabajo describe las caracteríısticas termoluminiscentes (TLde pastillas sinterizadas de Al2O3, para su posible uso como dosímetro TL de baja dosis. Pastillas de Al2O3 sinterizadas bajo diferentes condiciones decalcinación, con un diámetro de 5 mm y un espesor de 1 mm, fueron irradiadasa diferentes dosis usando una unidad de 60Co Theratron 780Cr enaire a temperatura ambiente. La lectura se realizó en un Harshaw TLD 4500.Las principales propiedades dosimétricas del material (curva de brillo, reproducibilidadde la respuesta, reutilización, linealidad y decaimiento térmicohan sido estudiadas en detalle. La curva de brillo de las pastillas sinterizadasde Al2O3 presenta un intenso

  15. El miedo al rey

    Directory of Open Access Journals (Sweden)

    François FORONDA

    2007-01-01

    Full Text Available La peur du roi. Sources et premières réflexions à propos d’une émotion aristocratique dans la Castille du XIVe siècleFace à un roi qui à présent pousse les effets de son ire jusqu’au meurtre pour faire le vide autour de lui et imposer sa différence souveraine, ses parents et les riches hommes, soit les principaux visés par cette politique de l’arbitraire qui enfreint les règles du jeu autant qu’elle contribue à les redéfinir, disent la peur (metus qu’ils ressentent, qu’ils utilisent aussi afin de donner à leur stratégie de pouvoir un fondement légitime. Et l’expression de cette émotion politique, qui tend à se muer en un stéréotype d’un discours aristocratique d’opposition, surtout présente dans les chroniques, mises ici en relation ici avec d’autres sources, notamment des correspondances, marque profondément l’histoire des relations souvent conflictuelles au sein de cette compagnie en définitive très étroite pendant un siècle, de la fin du XIIIe siècle à la fin du XIVe siècle. Cet article se propose d’ébaucher une première réflexion sur le sujet et d’en présenter les principales sources.El miedo al rey. Fuentes y primeras reflexiones acerca de una emoción aristocrática en la Castilla del siglo XIVFrente a un rey que ahora lleva hasta la muerte los efectos de su ira para hacer el vacío entorno a su persona e imponer su soberana, sus parientes y ricos hombres, o sea los principales afectados por esta política de la arbitrariedad que rompe las reglas del juego a la vez que contribuye a redefinirlas, dicen el miedo (metus que sienten, que utilizan también para darle a su estrategia de poder un fundamento legítimo. Y la expresión de esta emoción política, que tiende a convertirse en un estereotipo de un discurso aristocrático de oposición, sobre todo presente en la crónicas, aquí puestas en relación con otras fuentes, en particular cartas, marca profundamente la historia de

  16. CORRELACCIONES MATEMATICAS PARA LA OBTENCION DE RENDIMIENTO DE PRODUCCION, REMOCION DE CENIZAS Y PARTICION DE AGUA USANDO UN HIDROCICLON "SOLO AGUA"

    Directory of Open Access Journals (Sweden)

    JULIO ETAYO

    2009-01-01

    Full Text Available Se obtuvieron correlaciones matemáticas de rendimiento de producción, remoción de cenizas y partición de agua para describir el comportamiento de un hidrociclon "solo agua" (usa solamente agua como medio denso desde el punto de vista hidráulico y geométrico. Se utilizó un hidrociclón de 254mm de diámetro y un carbón de la mina la Yolanda (Valle del Cauca. La concentración másica de carbón usada fue entre 3.0 y 10.0% (p/p, la longitud del "vortex finder" entre 152.4 y 228.6mm y el diámetro del "apex" entre 19.1 y 44.5mm. A partir de las diferentes pruebas se obtuvieron rendimientos de producción entre 11.9 y 83.2% (p/p y remociones de cenizas entre 41.8 y 95.2% (p/p. Las ecuaciones matemáticas obtenidas presentaron factores de correlación superiores al 98.7% lo cual predice buena confiabilidad entre los resultados experimentales y los teóricos.

  17. Fabricación de electrodos para control de transporte y alineamiento a micro y nanoescalas usando técnicas bottom-up y top-down

    Directory of Open Access Journals (Sweden)

    Darwin Rodríguez

    2014-12-01

    Full Text Available El continuo avance de aplicaciones en dispositivos de autoensamble, posicionamiento, sensores, actuadores, y que permitan controladamente la manipulación de micro y nanoestructuras, han generado amplio interés en el desarrollo de metodologías que permitan optimizar la fabricación de dispositivos para el control y manipulación a micro y nanoescalas. Este proyecto explora técnicas de fabricación de electrodos con el fin de encontrar una técnica óptima y reproducible. Se compara el rendimiento de cada técnica y se describen protocolos de limpieza y seguridad. Se diseñan e implementan tres geometrías para movilizar y posicionar micro y nanopartículas de hierro en una solución de aceite natural. Finalmente se generan campos eléctricos a partir de electroforesis, con el fin de encontrar la curva que describe el desplazamiento de las partículas con respecto al potencial aplicado. Estos resultados generan gran impacto en los actuales esfuerzos de fabricación bottom-up (controlando con campos la ubicación y la movilidad en dispositivos electrónicos. El hecho de fabricar geometría planar con electrodos genera la posibilidad de que se pueda integrar movimiento de partículas a los circuitos integrados que se fabrican en la actualidad.

  18. Controle das emissões de chumbo particulado no entorno de uma reformadora de baterias da cidade do Rio de Janeiro usando ar como indicador

    Directory of Open Access Journals (Sweden)

    Simone Lorena Quiterio

    2003-04-01

    Full Text Available No período entre abril a julho de 1999, foram realizadas determinações dos níveis de chumbo no ar ambiente nas proximidades de uma reformadora de baterias (RB situada em Olaria (Rio de Janeiro, Brasil. A maioria das amostras coletadas a uma distância de até 25m da RB excederam o limite de 1,5µg.Pb.m-3 estabelecido pela Environmental Protect Agency (EPA, Estados Unidos. Esses resultados já foram publicados previamente (Quiterio et al., 2001. Neste trabalho, foram propostas a instalação de um sistema de exaustão Venture e algumas mudanças nos procedimentos operacionais. Após as modificações na RB, foi realizada uma nova campanha de monitoramento (agosto e setembro de 2000. As coletas foram realizadas nos três pontos considerados mais críticos, segundo as determinações anteriores. As concentrações medidas estiveram no intervalo 0,8-17,6µg.Pb.m-3, mostrando que as emissões de chumbo na atmosfera tiveram uma diminuição adequada. Contudo, a concentração na saída da chaminé é ainda maior que os limites estabelecidos pela EPA e, certamente, serão necessárias outras melhorias nas instalações e procedimentos.

  19. Análisis de la capacidad de servicio de mantenimiento de la cadena TRD Caribe Sancti Spíritus usando la simulación.

    Directory of Open Access Journals (Sweden)

    Manuel Hung Varela

    2014-09-01

    Full Text Available La investigación, tiene su origen en la necesidad de conocer, si la unidad de servicio de mantenimiento en la Cadena TRD Caribe Sancti Spíritus, es capaz de satisfacer o no las demandas de la Cadena, ya que se presenta una tendencia al crecimiento en la demanda, así como en las quejas por parte de los clientes que aseveraban largas esperas para ser servidos. Se definió el procedimiento para la simulación por eventos discretos a utilizar (Barceló Bugeda, 1996. Se definieron las fronteras del sistema, se construyó el modelo matemático para el sistema objeto de estudio y se programó en el software especializado Promodel 4.0. Para la simulación del modelo matemático, se recopiló información a través de técnicas como el muestreo aleatorio. El modelo fue verificado y validado (Barceló Bugeda, 1996; Aracil Santonja, 1995. Se simuló el modelo, haciendo uso del método de los lotes. Se procesaron los resultados de la simulación, y se concluyó que la unidad de servicio de mantenimiento no dispone de capacidad suficiente bajo las condiciones actuales para satisfacer las demandas de la cadena TRD Caribe en el territorio de Sancti Spíritus.

  20. El pensamiento frente al arte

    OpenAIRE

    Bergmann, Antonio

    2012-01-01

    Es un hecho histórico de gran importancia el que el hombre haya creado arte antes de haberse dedicado a la filosofía. Al mencionar esto no pienso en las pinturas pre-históricas que se encuentran en las cuevas de España y en el Sur de Francia, sino ante todo, en el arte egipcio y mesopotámico.  En Egipto y Mesopotamia --y Mesopotamia parece ser la región más importante -no nació sino que se creó al hombre humano, al hombre como ser arquitectónico.

  1. ANÁLISIS BAYESIANO DE ESTABILIDAD FENOTIPICA USANDO A PRIORI DE JEFFREYS BAYESIAN PHENOTYPIC STABILITY ANALYSIS USING JEFFREYS’S PRIOR

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    José Miguel Cotes Torres

    2006-06-01

    Full Text Available Uno de los métodos utilizados para evaluar estabilidad fenotípica es el propuesto por Shukla, el cual calcula la varianza de los genotipos dentro de la interacción genotipo por ambiente, para lo cual se hace uso de la estimación de los componentes de varianza dentro del análisis de varianza combinado. El acceso al cálculo de metodologías como REML e ML permitieron trabajar con datos que presentan algún grado de desbalance, sin embargo no solucionan de una manera adecuada el problema de la estimación de componentes de varianza negativos, los cuales son asumidos como cero y redistribuidos en los demás componentes positivos. El uso de la metodología bayesiana en la estimación de componentes de varianza resuelve satisfactoriamente este problema sin afectar los demás componentes. En este trabajo, se utilizaron datos de producción comercial de papa de 10 pruebas regionales realizadas en la región andina colombiana y se utilizó la metodología bayesiana en la solución del modelo mixto para la estimación de la varianza de Shukla con base en una distribución a priori no informativa de Jeffreys. Fueron obtenidas muestras de la distribución a posteriori conjunta mediante el algoritmo Independence Chain, con un tamaño de muestreo de 1,16x10(5 y un burnin de 500. Los resultados muestran que en la estimación REML de componentes de varianza tres genotipos presentan componentes de varianza estimados como cero. Las estimativas bayesianas son 89,35; 377,18 y 101,12; y los respectivos intervalos de credibilidad al 95% son: (2,13 - 371,70, (35,26 - 1363,67 y (2,33 - 434,53. Finalmente con estas estimativas no se afectó la estimación de los demás componentes de varianza.Shukla's variance is a very useful method for the analysis of phenotypic stability, computing the genotypic variance among the genotype by environment interaction, using variance component estimation of combined analysis of variance. New methodologies like REML or ML allow

  2. Estudio de la cinética de adsorción de Cu y Hg a partir de soluciones binarias usando quitosano

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    Martha Benavente

    2011-06-01

    Full Text Available In this work, the adsorption kinetic of Cu(II and Hg(II onto chitosan was studied from a binary solution at different initial concentration of metallic ions, at different particle sizes and agitation rate. Chitosan was obtained from shrimp shells. Solutions of 1 L of Cu(II and Hg(II were placed in contact with 2 g of chitosan and the mixture was agitated by 8 h. Afterwards, the samples were analysed by atomic absorption. The experimental data were tested by application of kinetic models of pseudo-first order and pseudo-second order. The results of adsorption process showed that in the most cases, both ions were effectively adsorbed by chitosan. The percentage of adsorption was 43-100 % and 94-100 % for Cu(II and Hg(II, respectively. The results also showed that at low concentrations, experimental data were better adjusted by pseudo-first order models; meanwhile, at high concentration, the data were well described by the pseudo-second model. Therefore, the rate-limiting step is the adsorption reaction and not mass transfer. Keywords: Adsorption kinetics; Binary solution; Chitosan; Kinetic models; Shrimp shell En este trabajo se estudió la cinética de adsorción de Cu(II y Hg(II en quitosano a partir de una solución binaria, a diferentes concentraciones iniciales de los iones metálicos, tamaño de partículas del adsorbente y velocidad de agitación. El quitosano fue extraído por métodos químicos de caparazón de camarón. Soluciones de 1 L de Cu(II y Hg(II fueron puestas en contacto con 2 g de quitosano y se agitaron por un período de 8 h. Al final del proceso, las muestras fueron analizadas en un espectrómetro de absorción atómica. Los datos experimentales fueron evaluados aplicando los modelos cinéticos de pseudo-primer orden y pseudo-segundo orden. Los resultados del proceso de adsorción de los iones metálicos Cu(II y Hg(II con quitosano, mostraron que en la mayoría de los casos, ambos iones fueron eficazmente adsorbidos por la

  3. Diseño de un molino para reciclar pastas de freno de tracto-camiones usando el método de bond

    Directory of Open Access Journals (Sweden)

    Arturo Ocampo Ramírez

    2015-01-01

    Full Text Available Actualmente existe en el trasporte público la necesidad de reemplazar constantemente las pastas de freno debido principalmente al factor de desgaste y por razones de seguridad. En este trabajo se propone crear las bases del diseño general de una máquina prototipo capaz de re-utilizar y reducir el tamaño de las pastas de freno del transporte público que están fuera de uso para ser empleadas como agente principal en una mezcla pastosa. Esta pasta se utilizará como material aislante en construcciones, recubrimiento de paredes y techos, así mismo en la elaboración de pavimentación en base sólida de calles. Para llevar a cabo esta propuesta se hace uso del método de Bond con el objetivo de estimar las dimensiones iniciales del molino y la potencia necesaria, mediante la creación de un programa numérico BM-Crush, evitando con esto construir molinos pilotos hasta donde esto es posible. Entre los principales resultados se obtiene la metodología general para calcular la potencia mecánica y las dimensiones necesarias del molino con base a cualquier cambio en las condiciones iniciales de operación, así como la distribución de los medios moledores y sus dimensionamiento. Se estima la velocidad crítica, estableciéndose con base en esto la velocidad optima con la que debe girar el molino de bolas.

  4. Consoer et al PFOS dataset

    Data.gov (United States)

    U.S. Environmental Protection Agency — This ScienceHub entry was developed for the published paper: Consoer et al., 2016, Toxicokinetics of perfluorooctane sulfonate in rainow trout (Oncorhynchus...

  5. DESAFÍOS AL ORDEN

    Directory of Open Access Journals (Sweden)

    Evangelina De los Rios

    2012-03-01

    Full Text Available Fradkin, Raúl y Gelman, Jorge (Compiladores, Desafíos al Orden. Política y sociedades rurales durante la Revolución de Independencia, Prohistoria ediciones, Rosario, 2008, 157 pp.

  6. Seltzer_et_al_2016

    Data.gov (United States)

    U.S. Environmental Protection Agency — This dataset supports the modeling study of Seltzer et al. (2016) published in Atmospheric Environment. In this study, techniques typically used for future air...

  7. Note intorno al Teatro Vagante

    OpenAIRE

    Scabia, Giuliano

    2013-01-01

    In questo testo-intervista Scabia traccia, alternando racconto e riflessione, un percorso che abbracciatutta l'attività del suo Teatro Vagante: dalle azioni nelle scuole degli inizi degli anni '70 - agli alboridell'Animazione Teatrale, che anche da qui prese le mosse - al lavoro all'Università di Bologna,organica continuazione di quei primi esperimenti. Dalla poesia alle azioni teatrali in strada;dall'architettura della pagina al respiro della parola detta in presenza ; dalle aule ...

  8. Information als Gegenstand von Informationskompetenz

    OpenAIRE

    Ingold, Marianne

    2011-01-01

    Der Informationsbegriff als zentraler Gegenstand von Informationskompetenz wird in der bibliothekarischen Diskussion in der Regel nicht explizit thematisiert, sondern lässt sich aus Fachliteratur und Bibliothekspraxis nur implizit erschließen. Eine theoretische Beschäftigung mit dem Informationsbegriff ist jedoch unabdingbar, soll das Konzept "Informationskompetenz" auch außerhalb des bibliothekarischen Kontextes verständlich und nutzbar gemacht werden. Im vorliegenden Text, der sich als Beit...

  9. Response to Brosch et al.

    OpenAIRE

    Pihlajamäki, Jussi; Lerin, Carles; Kaminska, Dorota; Venesmaa, Sari; Itkonen, Paula; Boes, Tanner; Floss, Thomas; Schroeder, Joshua; Dearie, Farrell; Crunkhorn, Sarah; Burak, Furkan; Jimenez-Chillaron, Josep C.; Kuulasmaa, Tiina; Miettinen, Pekka; Park, Peter J.

    2012-01-01

    We would like to respond to Brosch et al. regarding our manuscript “Expression of the Splicing Factor Gene SFRS10 Is Reduced in Human Obesity and Contributes to Enhanced Lipogenesis” (Pihlajamäki et al., 2011b). Brosch performed RT-PCR in liver samples from 13 lean and 34 obese individuals, finding no differences in SFRS10 or LPIN1 expression. We wish to address points raised by Brosch, including experimental strategy and analysis of human SFRS10 expression.

  10. ¿Por qué enseñar a escribir usando técnicas de "Focus on Form"?

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    Rosa Mª Lucha Cuadros

    2006-05-01

    Full Text Available El estudio que aquí presentamos aborda los siguientes temas: 1. Indaga acerca de si una enseñanza intensiva centrada en la forma induce o no a obtener resultados más positivos en la adquisición, al menos en la memoria a corto plazo, de estructuras lingüísticas significativas; en nuestro caso estructuras para comparar y expresar ventajas e inconvenientes. 2. Permite postular la efectividad del uso de herramientas informáticas para evaluar la “calidad de información” (Díaz y Ruggia 2004 de producciones escritas. Las herramientas utilizadas han sido, por un lado, el analizador-etiquetador Connexor, y, por otro lado, el software Childes (MacWhinney 1987, formado por diferentes programas informáticos, que permite la cuantificación automática de la frecuencia de aparición de categorías sintácticas elegidas previamente. En la investigación participaron dos grupos de estudiantes del programa Erasmus de la Universitat Pompeu Fabra. El primer grupo recibió una enseñanza intensiva centrada en la forma tras la cual realizó una tarea de expresión escrita consistente en la redacción de un texto expositivo. El segundo grupo realizó la misma tarea de expresión escrita, pero sin la previa instrucción centrada en la forma. //// The present study analyses the effectiveness of instructed second language teaching through focus on form in a group of learners compared with a control group. Written production was elicited through a final task after refreshing grammar and lexis content in the experimental group while the control just did the final task. The final product of both students’ groups was analysed with semiautomatic processors (Childes and Connexor and the patterns resulting compared and evaluated separately. Data show that the experimental group, which underwent treatment, did perform more native-like than the control group.

  11. Dosimetria em folículos tireoidianos devido aos elétrons de baixa energia do iodo usando o método Monte Carlo Dosimetry in thyroid follicles due to low-energy electrons of iodine using the Monte Carlo method

    Directory of Open Access Journals (Sweden)

    Laélia Campos

    2008-12-01

    Full Text Available OBJETIVO: Avaliar a dose absorvida em folículos tireoidianos devido aos elétrons de baixa energia, como os elétrons Auger e os de conversão interna, além das partículas beta, para os radioisótopos de iodo (131I, 132I, 133I, 134I e 135I usando o método Monte Carlo. MATERIAIS E MÉTODOS: O cálculo da dose foi feito ao nível folicular, simulando elétrons Auger, conversão interna e partículas beta, com o código MCNP4C. Os folículos (colóide e células foliculares foram modelados como esferas, com diâmetros do colóide variando de 30 a 500 mm. A densidade considerada para os folículos foi a da água (1,0 g.cm-³. RESULTADOS: Considerando partículas de baixa energia, o percentual de contribuição do 131I na dose total absorvida pelo colóide é de aproximadamente 25%, enquanto os isótopos de meia-vida física curta apresentaram contribuição de 75%. Para as células foliculares, esse percentual é ainda maior, chegando a 87% para os iodos de meia-vida curta e 13% para o 131I. CONCLUSÃO: Com base nos resultados obtidos, pode-se mostrar a importância de se considerar partículas de baixa energia na contribuição para a dose total absorvida ao nível folicular (colóide e células foliculares devido aos radioisótopos de iodo (131I, 132I, 133I, 134I e 135I.OBJECTIVE: To evaluate the absorbed dose in thyroid follicles due to low-energy electrons such as Auger and internal conversion electrons, besides beta particles, for iodine radioisotopes (131I, 132I, 133I, 134I and 135I utilizing the Monte Carlo method. MATERIALS AND METHODS: The dose calculation was performed at follicular level, simulating Auger, internal conversion electrons and beta particles, with the MCNP4C code. The follicles (colloid and follicular cells were modeled as spheres with colloid diameter ranging from 30 to 500 mm, and with the same density of water (1.0 g.cm-³. RESULTS: Considering low-energy particles, the contribution of 131I for total absorbed dose to

  12. Surgeons overestimate the risk of malignancy in thyroid nodules. Evaluation of subjective estimates using a Bayesian analysis Los cirujanos sobreestiman el riesgo de malignidad de los nódulos tiroideos. Evaluación de los estimados subjetivos usando un análisis bayesiano

    Directory of Open Access Journals (Sweden)

    Alvaro Sanabria

    2011-06-01

    subjetivas.
    Objetivo. Determinar las probabilidades subjetivas asignadas a las característi-cas clínicas de un paciente con un nódulo tiroideo, para evaluar el grado de in-fluencia de estas probabilidades en la sospecha clínica final de malignidad en comparación con los datos objetivos.
    Materiales y métodos. Se diseñó un análisis bayesiano para predecir el riesgo de malignidad en un nódulo tiroideo basado en la relación causal conocida de factores clínicos y demográficos durante la primera consulta. Se desarrolló un modelo con las variables clínicas y demográficas usando como expertos a los ci-rujanos.
    Resultados. La mayor probabilidad de malignidad (94% se asignó al caso clíni-co de un hombre mayor de 60 años, con disfonía y disfagia, nódulo de creci-miento rápido, antecedentes de radioterapia cervical y familiar con cáncer de ti-roides, con nódulos múltiples, mayores de 1 cm de consistencia dura y con adenomegalias cervicales palpables. Para los casos de bajo riesgo, con nódulos sin características de malignidad, la probabilidad de malignidad asignada por los clínicos fue de 33,59%, para los de alto riesgo fue de 75,54%.
    Conclusión. Los cirujanos toman decisiones diagnósticas basadas en creen-cias subjetivas que no necesariamente corresponden con los datos objetivos de las características de nódulos.

  13. Desenvolvimento de software e hardware para irrigação de precisão usando pivô central Development of software and hardware for precision irrigation using the center pivot

    Directory of Open Access Journals (Sweden)

    Tadeu M. de Queiroz

    2008-03-01

    Full Text Available O presente trabalho teve por objetivo desenvolver softwares e hardwares para aplicação ao monitoramento e controle automático para a irrigação de precisão usando sistemas do tipo pivô central. O trabalho foi desenvolvido no Departamento de Engenharia Rural - LER, da Escola Superior de Agricultura "Luiz de Queiroz" - ESALQ, da Universidade de São Paulo - USP, em Piracicaba - SP. Foram utilizados componentes eletrônicos discretos, circuitos integrados diversos, módulos de radiofreqüência, microcontroladores da família Basic Step e um microcomputador. Foram utilizadas as linguagens Delphi e TBasic. O hardware é constituído de dois circuitos eletrônicos, sendo um deles para "interface" com o computador e o outro para monitoramento e transmissão da leitura de tensiômetros para o computador via radiofreqüência. Foram feitas avaliações do alcance e da eficiência na transmissão de dados dos módulos de radiofreqüência e do desempenho do software e do hardware. Os resultados mostraram que tanto os circuitos quanto os aplicativos desenvolvidos apresentaram funcionamento satisfatório. Os testes de comunicação dos rádios indicaram que esses possuem alcance máximo de 50 m. Concluiu-se que o sistema desenvolvido tem grande potencial para utilização em sistemas de irrigação de precisão usando pivô central, bastando para isso que o alcance dos rádios seja aumentado.The objective of this work was to develop softwares and hardwares applied to the management and automatic control for precision irrigation using center pivot systems. They were developed in the Rural Engineering Department - LER, at the "Luiz de Queiroz" College of Agriculture - ESALQ, of São Paulo University - USP, in Piracicaba, SP-Brazil. It was used discrete electronic components, several integrated circuits, radio frequency modules, microcontrollers from the Basic Step family and a microcomputer. The computer software was developed in Delphi language, and

  14. D’al-Ẓāhir Baybars à ʿAlī al-Zaybaq

    OpenAIRE

    Dorlian, Georges

    2014-01-01

    « Toi par le courage, moi par la filouterie » aimait répéter Baṭṭāl à la princesse Ḏāt al-Himma, comme pour délimiter les espaces d’action revenant à chacun. Et d’ajouter, pour mieux dépeindre son rôle : « Mon métier n’est pas celui de la guerre, des armes et des exploits, mais celui de la ruse et de la fourberie dans un château fort ou une forteresse. » Baṭṭāl était un ʿayyār adjoint à la princesse Ḏāt al-Himma et à ʿAbd al-Wahhāb pour servir leur cause sublime et leur idéal chevaleresque. E...

  15. Prevalência e fatores associados à infecção pelo Mycobacterium tuberculosis entre agentes comunitários de saúde no Brasil, usando-se a prova tuberculínica

    Directory of Open Access Journals (Sweden)

    Wesley Pereira Rogerio

    2015-10-01

    Full Text Available Resumo Este artigo tem por objetivo determinar a prevalência e os fatores associados à infecção latente pelo Mycobacterium tuberculosis entre agentes comunitários de saúde (ACS, usando dois pontos de corte da prova tuberculínica 5mm e 10mm. Trata-se de estudo transversal, com dados coletados sobre sexo, idade, cicatriz de BCG, prova tuberculínica (PT anterior, tempo que trabalha na profissão de ACS, atuar em unidade básica de saúde (UBS, ter tido contato intradomiciliar com tuberculose (TB, usar álcool, ser fumante e apresentar comorbidades. Para controle de variáveis de confusão e estimativa da medida de efeito (OR, foi empregada a regressão logística. Aplicou-se PT, com leitura após 48-72 horas. As prevalências foram de 57,88% e 37,3%, respectivamente, para 5mm e 10mm. Manteve-se associada à positividade para o ponto de corte de 10mm a condição de trabalhar em UBS com Programa de Controle de Tuberculose (PCT implementado e já ter tido contato intradomiciliar com TB. Já para o ponto de corte de 5mm, trabalhar em UBS com PCT e implementado. São necessárias ações de conscientização nos municípios e fortalecimento das ações de educação permanente sobre a temática.

  16. Intermittent water discharges for family orchards using photovoltaic energy and a system self-operating for a TDF; Riego intermitente para huertos familiares usando energia fotovoltaica y un sistema auto-operante para un TDF

    Energy Technology Data Exchange (ETDEWEB)

    Millan Diaz, Candido; Garcia Villanueva, Nahun H [Instituto Mexicano de Tecnologia del Agua, Jiutepec, Morelos (Mexico); Sanchez Juarez, Aaron [Centro de Investigacion en Energia, UNAM, Temixco, Morelos (Mexico)

    2000-07-01

    This work present the design of a system for automatic opening and closing of a Discharge Bottom Tank (DBT) to produce intermittent water discharges. In order to modernize and increase the production in the family orchards, the application of a integral system built with a self-operating opening and closing valve, a DBT and a PV water pumping system, is suggested. The results obtained from this integral system, is suggested. The results obtained from this integral system applied in a family experimental farm of 144 m{sup 2} are shown below. The PV system size for pumping the required water per day for that family prototype farm was of 106 W-p. Comparing the yield obtained for green tomato, red tomato, and squash in existing technical irrigation process against our integral system, it is shown that our production is almost the same. [Spanish] En este trabajo se presenta el diseno de un sistema de apertura y cierre automatico para producir descargas de agua intermitentes en un Tanque de Descarga de Fondo (TDF). Con el objeto de aumentar la produccion agricola en los huertos familiares, se sugiere la aplicacion de un sistema integral, para riego intermitente en ellos, formado por: el sistema auto operante disenado, un TDF y un sistema de bombeo fotovoltaico, como una alternativa para modernizar y mejorar las eficiencias del riego por gravedad en ellos. Se dan a conocer los resultados obtenidos de este sistema integral en un huerto familiar experimental de 144 m{sup 2}. El tamano del sistema de bombeo fotovoltaico para extraer el agua requerida por dia-cultivo para ese huerto familiar prototipo fue de 106 W-p. El rendimiento por hectarea obtenido para cultivos de jitomate, tomate y calabacita muestra que nuestra produccion, usando el sistema integral, es comparable con los rendimientos por hectarea que se obtienen con metodologias de riego tecnificadas.

  17. Immunoblot analysis using antigen from Taenia crassiceps cysticerci in the diagnosis of swine cysticercosis Análisis del inmunoblot usando antígeno de cisticercos de Taenia crassiceps en el diagnóstico de la cisticercosis

    Directory of Open Access Journals (Sweden)

    Paulo Sérgio de Arruda Pinto

    2001-01-01

    Full Text Available Se utilizó la técnica del inmunoblot para el diagnóstico de la cisticercosis porcina usando un antígeno total de cisticercos de Taenia crassiceps. Fueron analizados 13 sueros del cerdo con cisticercosis, 30 sueros controles negativos y ocho sueros del cerdo con hidatidosis, así como nueve del suino con macracantorincosis, 10 con ascaridiosis y ocho con pulmonía. El uso de este antígeno en el inmunoblot con suero de cerdos no se había publicado previamente. El inmunoblot fue padronizado por análisis de titulación en bloque mostrando 100.0% de sensibilidad y 96.7% de especificidad. Los péptidos específicos para la cisticercosis en orden de frecuencia fueron: 72-68 kD (100%, 16-15 kD (77%, 39-36 kD (62%, 18-17 kD (54%, 21 kD (31%, 14 kD (23%, 25-23 kD (8%, y 20-19 kD (8%. Reacción cruzada (72-68 y 18-17 kD sólo se descubrió en una muestra (12.5% de cerdo con hidatidosis. Debido a sus altas tasas de desempeño, el inmunoblot debe ser útil para confirmar el diagnóstico de cisticercosis porcina y es más eficaz que otras pruebas empleadas para este propósito, como examen de la lengua, examen anatomopatológico y ELISA

  18. Estudio de la Incertidumbre en la Programación de Actividades usando la Matriz de Estructura Dependiente Study of the Uncertainty of Task Programming using the Dependency Structure Matrix

    Directory of Open Access Journals (Sweden)

    Edelmira D Gálvez

    2012-01-01

    Full Text Available Se presenta un estudio sobre el efecto de la incertidumbre en la programación de actividades de proyectos usando la matriz de estructura dependiente (DSM y la teoría gris. Se aplica la teoría gris para representar la incertidumbre en la estimación del tiempo de duración de proyectos, desarrollando las ecuaciones necesarias para determinar el tiempo convencional gris, el tiempo normal gris y el tiempo normal gris con superposición natural. Con base en el estudio se concluye que la aplicación de la teoría de gris a la DSM permite: i considerar la incertidumbre en la programación del proyecto; ii identificar las etapas más críticas; iii analizar el efecto de la incertidumbre de cada etapa en la duración total del proyecto; y iv comparar diferentes estrategias de programación.A study about the effect of uncertainty on the planning of project activities using the dependency structure matrix (DSM and grey theory. The grey theory is applied to represent the uncertainty in estimating project extension. As a result, the equations to determine the grey conventional time, the grey normal time and the grey normal time with natural overlap were developed. Based on the case studies it is concluded that the application of the grey theory to the DSM allows: considering the uncertainty in project planning; ii identifying the most critical stages; iii analyzing the effect of the uncertainty of each stage in the total project duration; and iv comparing different programming strategies.

  19. Análisis de la variación genética en clones de caucho (Hevea brasiliensis de Asia, Suramérica y Centroamérica usando marcadores RAPD

    Directory of Open Access Journals (Sweden)

    Hernández R César Augusto

    2006-12-01

    Full Text Available El caucho natural (Hevea brasiliensis representa a especies potenciales para reforestación y programas de explo­tación comercial en ciudades tropicales como Colombia. La variabilidad genética de una colección de caucho que se encuentra en la Estación experimental de Paraguaycito en Buenavista, departamento del Quindio en Colom­bia fue estudiada para aumentar el conocimiento en cuanto a las especies y realizar un mejor uso de los árboles disponibles. Un total de 25 clones, seis de Sur América, 17 de Asia y 2 de América Central fueron seleccionados y analizados usando RAPDs. Las muestras aisladas de ADN de los árboles fueron con 102 primers, 23 de los cuales mostraron polimorfismos. Aunque se encontró un alto grado de similaridad, los análisis grupales de datos llevaron a diferenciar los árboles de de caucho en términos de su origen geográfico. Por lo tanto, las relaciones genéticas que se encontraron entre los clones podrían ayudar a seleccionar parentales para uso en programas de reproducción y diseño de estrategias para la conservación de los clones que tengan características agronómicas deseables. Palabras clave: identificación de cultivos, distancia genética, diversidad genética, Hevea brasiliensis, marcadores RAPD.

  20. Evaluation of a Heating System in Poultry Houses Using a CFD Model / Evaluación de un Sistema de Calefacción en Galpones Avicolas Usando un Modelo en CFD

    Directory of Open Access Journals (Sweden)

    Flávio Alves Damasceno

    2014-06-01

    Full Text Available Abstract.. The objective of this study was to adapt and validate a computer model using the Computational Fluid Dinamics (CFD, in the prediction of temperature and air speed in a duct distribution system coupled to a heating furnace that is used in typical poultry houses in tropical and subtropical countries. The validation of the model with experimental data was satisfactory, presentingnormalized mean square error NMSE values of 0.25 and 0.02 for air temperature and air speed, respectively. The results evidenced that the proposed model is adequate for predicting the air speed and temperature for this type of system, and could be used to improve the efficiency of the distribution of heat inside and around air ducts using different air speeds, types of materials and dimensions. / Resumen. El objetivo de este estudio fue adaptar y validar un modelo computacional haciendo uso de la dinámica de fluidos computacional (CFD para predecir la temperatura y la velocidad del aire en un sistema de distribución de ductos acoplado a un sitema de calefacción que es utilizado en las instalaciones avícola en los países tropicales y subtropicales. La validación del modelo con los datos experimentales fue satisfactoria, presentando valores medios normalizados del error cuadrado NMSE de 0,25 y 0,02 para la temperatura y velocidad del aire respectivamente. Los resultados muestran que el modelo propuesto es adecuado para predecir la velocidad del aire y la temperatura alrededor de este tipo de sistema, y podría ser utilizado para mejorar la eficiencia la distribución de calor en el interior y alrededor de los conductos, usando diferentes velocidades, tipos de materiales y dimensiones. 

  1. Correlación de Propiedades de Aceites Vegetales y Sebo Vacuno Usando Aproximantes de Padé Correlation of Vegetable Oil and Beef Tallow Properties Using Padé Approximants

    Directory of Open Access Journals (Sweden)

    Mónica P Guerrero

    2008-01-01

    Full Text Available Se han utilizado los aproximantes de Padé para correlacionar algunas propiedades necesarias para el diseño y modelado de intercambiadores de calor de tubo y coraza usados en procesos de elaboración de aceites vegetales y sebo vacuno y en la producción de biodiesel, entre otras aplicaciones. Los aproximantes de Padé son funciones racionales que tienen la capacidad de representar funciones complejas con un número reducido de parámetros. Se ha considerado la densidad, el calor específico, la viscosidad y la conductividad térmica de estas sustancias y se han determinado los parámetros del modelo estudiado usando datos experimentales de estas propiedades. El modelo de Padé usado muestra ser adecuado para el cálculo de las propiedades estudiadas obteniendo desviaciones similares o inferiores a otros modelos altamente no lineales.Padé approximants have been used to correlate some properties needed in the modeling and design of shell and tube heat exchangers used in the production of vegetables oils, beef tallow and biodiesel. Padé approximants are rational functions that have the capacity of representing complex functions with a reduce number of parameters. The properties considered were density, specific heat, viscosity and thermal conductivity of these substances and model parameters were determined using experimental data from the literature. The proposed general Padé model shows to be adequate to estimate the properties studied, obtaining deviations similar or lower than those of other highly non-linear models.

  2. Estudo do efeito de memória de forma em ligas inoxidáveis usando ensaio de compressão Study of shape memory effect in stainless steel using compression tests

    Directory of Open Access Journals (Sweden)

    Fabiana Cristina Nascimento

    2010-09-01

    Full Text Available As propriedades de recuperação de forma da liga à base de Fe-Mn-Si-Cr-Ni-Co foram estudadas usando ensaio de compressão. Foram analisadas medidas de recuperação elástica (Re, recuperação de forma (Rf e recuperação de forma total (R T = Re + Rf em função do número de ciclos de treinamento. Os resultados indicaram que 3,3 foi a melhor razão entre altura (h o = 20 mm e diâmetro (φo = 6 mm para se conseguirem uma deformação homogênea e curvas de carregamento bem definidas. A maior contribuição para a R T foi atribuída à recuperação de forma. No último ciclo de treinamento, foi obtida uma R T = 90%, sendo 25% atribuída a Re.The shape recovery properties of an Fe-Mn-Si-Cr-Ni-Co based alloy were studied using compression tests. Analyzed were the elastic recovery (Er, shape recovery (Sr and total shape recovery (T SR = Er + Sr measurements as a function of training cycles. The results indicated that 3.3 was the best ratio between height (h o = 20 mm and diameter (φo = 6 mm to obtain a homogeneous deformation and defined loading curves. A major contribution of T SR was attributed to shape recovery. In the last training cycle, a T SR = 90 % was obtained, where 25% was attributed to Er.

  3. Estudio de fallas incipientes en rodamientos usando la técnica de la envolvente y cepstrum Study on incipient fault bearing detection based on enveloping and cepstrum techniques

    Directory of Open Access Journals (Sweden)

    Jabid E Quiroga

    2012-12-01

    Full Text Available Este artículo presenta un estudio comparativo del desempeño de los métodos de detección de fallas incipientes en rodamientos FFT, envolvente y cepstrum usando señales de vibración. Diferentes condiciones de fallas son estudiadas, desde incipientes hasta severas a través de un banco de prueba construido para ese propósito. Adicionalmente se utilizan registros de vibraciones obtenidos en el website (CWRU, de Case Western Reserve University, para evaluar el desempeño de las técnicas. Las técnicas de FFT, envolvente y cepstrum implementadas en ambiente Matlab® son aplicadas a las señales de vibración en cada caso de estudio. Envolvente y cepstrum muestran un desempeño satisfactorio en detección de fallas incipientes, ubicándolas como técnicas apropiadas para ser parte de un sistema de monitoreo en máquina rotativa.This paper presents a comparative study to determine the performance of FFT, Enveloping and cepstrum incipient bearing fault detection techniques using vibration signal. Differentfault scenarios are executed in an experimental test bench from incipient to severe conditions in order to evaluate each technique. Additionally, vibration information given by Case Western Reserve University (CWRU website is also used to evaluate both techniques. FFT, enveloping and cepstrum techniques are implemented in Matlab® environment to detect each fault condition. Enveloping and cepstrum provide satisfactory results in fault detection. Therefore, they can be suitable candidates to be used in a rotative machine condition monitoring system.

  4. Strain sensing with sub-micron sized Al-AlOx-Al tunnel junctions

    OpenAIRE

    Koppinen, P. J.; Lievonen, J. T.; Ahlskog, M.; Maasilta, I. J.

    2009-01-01

    We demonstrate a local strain sensing method for nanostructures based on metallic Al tunnel junctions with AlOx barriers. The junctions were fabricated on top of a thin silicon nitride membrane, which was actuated with an AFM tip attached to a stiff cantilever. A large relative change in the tunneling resistance in response to the applied strain (gauge factor) was observed, up to a value 37. This facilitates local static strain variation measurements down to ~10^{-7}.

  5. Epistemologi Sufi : Perspektif Al-Hakim Al-Tirmidzi

    OpenAIRE

    Ainul Abidin Shah

    2012-01-01

    Abstract : This article deals with some epistemological terms and theoretical postulates in the thought of a well known sufi  from the 9th century AD., Abu `Abdu’lLah Muhammad b. `Ali al-Hakim al-Tirmidzi, in order to describe the path (sulūk) of a sufi towards the Ultimate Reality. In his own style thought about the sufis, placing an emphasis upon the strong relations between the walāyah (sufi  sainthood) and the ma`rifa (sufi knowledge) in the one side, and between the two a philosophy of Sufi Et...

  6. Al clamor de les vuvuzeles

    Directory of Open Access Journals (Sweden)

    Javier Olivera Betrán

    2010-09-01

    Full Text Available El Mundial de Futbol de Sud-àfrica ha situat l’Àfrica al mapa mundial i ha mostrat al món el triomf de l’estil de futbol d’Espanya basat en la col·lectivitat, l’esperit d’equip, la humilitat, la cohesió interna i el joc bonic. L’organització africana, seriosa i eficaç, ha sabut mobilitzar i il·lusionar la població del país que ha participat en el mundial des de l’orgull de ser africà, amb l’esperit alegre, festiu i també reivindicatiu de la gent de l’Àfrica. Aquest esdeveniment suposa el llançament de la marca “Sud-àfrica” al món amb un avís clar d’optar a l’organització d’uns primers Jocs Olímpics a Àfrica (potser els de 2020. S’obre una finestra d’esperança al segle xxi per al continent perdut de la mà de l’esport espectacle tan universal, massiu, emocional i mercantil que també es juga a la canxa de la política i de l’economia.

  7. A united refinement technology for commercial pure Al by Al-10Ti and Al-Ti-C master alloys

    International Nuclear Information System (INIS)

    Because flake-like TiAl3 particles in Al-Ti-C master alloys prepared in a melt reaction method dissolve slowly when they are added into Al melt at 720 deg. C, Ti atoms cannot be released rapidly to play the assistant role of grain refinement, leading to a poor refinement efficiency of Al-Ti-C master alloys. A united refinement technology by Al-10Ti and Al-Ti-C master alloys was put forward in this paper. The rational combination of fine blocky TiAl3 particles in Al-10Ti and TiC particles in Al-Ti-C can improve the nucleation rate of α-Al. It not only improves the grain refinement efficiency of Al-Ti-C master alloys, but also reduces the consumption

  8. Modeling of the ALS linac

    International Nuclear Information System (INIS)

    The ALS injector linac is used for the Beam Test Facility (BTF) and the Damping Experiments when it is available in between the ALS filings. These experiments usually require higher quality beams and a better characterization than is normally required for ALS operations. This paper focuses on the beam emittance, energy tilt, and especially the longitudinal variation of the beam parameters. For instance, the authors want to avoid longitudinal variations at the low beta section of the BTF. On the other hand, a large energy tilt is required for post-acceleration compression of the bunch using an alpha magnet. The PARMELA code was modified to calculate and display longitudinal variations of the emittance ellipse. Using the Microsoft Development Studio under Windows NT environment the code can handle a much larger number of particles than was previously possible

  9. Conjuntivitis alérgica

    Directory of Open Access Journals (Sweden)

    Alejandro Tello Hernández

    2008-07-01

    Full Text Available La conjuntivitis alérgica es una de las causas más comunesde consulta externa en oftalmología y tiene una muy altarelación con las reacciones alérgicas sistémicas. Lafisiopatología de las reacciones de hipersensibilidad noshace entender los cuadros clínicos característicos de estapatología y sus diferentes grados de severidad. Eldiagnostico diferencial es amplio, sin embargo hay clavesdiagnosticas que nos orientan rápidamente al diagnosticocorrecto. El tratamiento se enfoca en las medidasfarmacológicas y no farmacológicas, utilizándolas enconjunto para disminuir la recurrencia del cuadro y prevenirsecuelas visuales.

  10. ALS:A SAIRASTAVAN TOIMINTATERAPIA

    OpenAIRE

    Vuorinen, Johanna

    2013-01-01

    Amyotrofinen lateraali skleroosi on harvinainen, etenevä sairaus. Sairaus surkastuttaa edetessään potilaan tahdonalaisen lihaksiston. Sairauden oireet näkyvät yleensä ensin raajoissa, mutta myös nielun lihaksista alkava bulbaarinen taudinmuoto on mahdollinen. ALS voi myös aiheuttaa frontotemporaalista dementiaa. Sairaus etenee yksilöllisesti, mutta sen kesto on yleensä noin 3-5 vuotta. Keski-Suomen keskussairaalassa ALS:n sairastuneen kuntoutukseen osallistuu moniammatillinen työryhmä, j...

  11. Diseño y puesta en marcha de un "sistema semicontinuo en dos etapas: hidrólisis • fermentación" para la producción de etanol a partir de almidón de papa usando simultáneamente aspergillus nigery saccharomyces cerevisiae

    OpenAIRE

    Amleto León Téllez; Graciela Chalela Alvarez; Alba Lucía Roa

    2010-01-01

    Se describe el diseño y evaluación de las variables que gobiernan el sistem semicontinuo en dos etapas: hidrólisis fermentación para la producción de etanol a partir de almidón de papa usando simultáneamente Aspergillus niger y Saccharomyces cerevisiae, con resultados comparables a los del método clásico de monocultivo pero con tiempos de bioproducción inferiores. La hidrólisis del almidón y posterior fermentación produjo cantidades significativas de biomasa, azúcares simples, y enzimas...

  12. Formação de biofilme em aço inoxidável por Aeromonas hydrophila e Staphylococcus aureus usando leite e diferentes condições de cultivo Biofilm formation by Aeromonas hydrophila and Staphylococcus aureus on stainless steel using milk and different conditions of cultivation

    OpenAIRE

    Cleube Andrade Boari; Mariana Pereira Alves; Victor Maximiliano Reis Tebaldi; Taciana Villela Savian; Roberta Hilsdorf Piccoli

    2009-01-01

    O objetivo desta pesquisa consistiu em avaliar a formação de biofilme em aço inoxidável por Aeromonas hydrophila e Staphylococcus aureus usando leite e diferentes condições de cultivo. As variáveis em estudo consistem no cultivo monoespécie e combinado, dos referidos microrganismos e nas temperaturas de 4, 7 e 18 °C. Recipientes contendo 1000 mL de leite, densidade populacional de 10(5) UFC.mL-1 de cada microrganismo e 10 cupons de aço inoxidável (10 × 20 mm) foram lacrados e armazenados, sob...

  13. Generation and evolution of nanoscale AlP and Al13Fe4 particles in Al-Fe-P system

    International Nuclear Information System (INIS)

    Highlights: • Diffusion and gradual solid reactions between Al and FexP phases in Al-Fe-P alloy were investigated. • Nanoscale AlP clusters are in-situ generated and evolve during the whole process. • This novel Al-Fe-P alloy has an excellent low-temperature refining performance on hypereutectic Al-Si alloy. - Abstract: In this paper, the gradual solid reactions between Al and FexP phases in Al-Fe-P alloy were investigated. The results show that the whole reaction process undergoes four main stages: the diffusion of Al atom, the generation of (Al, Fe, P) intermediate compound, the precipitation of nano AlP and Al13Fe4 clusters and their growth to submicron particles. The microstructure of Fe-P particles evolves from the “egg-type”, the “sponge-type” to the “sesame-cake” structure. AlP and Al13Fe4 nano phases have in-situ generated and evolved during the whole process. The gradual reaction mechanism has been discussed. Furthermore, a novel Al-Fe-P alloy which contains (Al, Fe, P) intermediate compounds and nano AlP particles has been synthesized and its low-temperature refining performance on A390 alloy has also been investigated

  14. Dynamic Modeling of ALS Systems

    Science.gov (United States)

    Jones, Harry

    2002-01-01

    The purpose of dynamic modeling and simulation of Advanced Life Support (ALS) systems is to help design them. Static steady state systems analysis provides basic information and is necessary to guide dynamic modeling, but static analysis is not sufficient to design and compare systems. ALS systems must respond to external input variations and internal off-nominal behavior. Buffer sizing, resupply scheduling, failure response, and control system design are aspects of dynamic system design. We develop two dynamic mass flow models and use them in simulations to evaluate systems issues, optimize designs, and make system design trades. One model is of nitrogen leakage in the space station, the other is of a waste processor failure in a regenerative life support system. Most systems analyses are concerned with optimizing the cost/benefit of a system at its nominal steady-state operating point. ALS analysis must go beyond the static steady state to include dynamic system design. All life support systems exhibit behavior that varies over time. ALS systems must respond to equipment operating cycles, repair schedules, and occasional off-nominal behavior or malfunctions. Biological components, such as bioreactors, composters, and food plant growth chambers, usually have operating cycles or other complex time behavior. Buffer sizes, material stocks, and resupply rates determine dynamic system behavior and directly affect system mass and cost. Dynamic simulation is needed to avoid the extremes of costly over-design of buffers and material reserves or system failure due to insufficient buffers and lack of stored material.

  15. Cathodic electrochemiluminescence at double barrier Al/Al2O3/Al/Al2O3 tunnel emission electrodes

    International Nuclear Information System (INIS)

    Double insulating barrier tunnel emission electrodes were fabricated by adding a new pure aluminum layer upon oxidized aluminum electrodes by vacuum evaporation and thermally oxidizing the new aluminum layer in air at room temperature. Resulting Al/Al2O3/Al/Al2O3 electrodes allow the use of various aluminum alloys in the electrode body necessary for hardness or shaping ability of the electrode while obtaining the luminescence properties of pure aluminum oxide. During electrical excitation of luminescent labels by cathodic hot electron injection into aqueous electrolyte solution, the background noise is mainly based on high-field-induced solid-state electroluminescence and F-center luminescence of the outer aluminum oxide film. The more defect states and/or impurity centers the outer oxide film contains, the higher is the background emission intensity. The present electrode fabrication method provides a considerable improvement in signal-to-noise ratio for time-resolved electrochemiluminescence (TR-ECL) measurements when the original native oxide film of the electrode body contains luminescence centers displaying long-lived luminescence. The excellent performance of the present electrodes is demonstrated by extremely low-level detection of Tb(III) chelates, luminol, Pt(II) coproporphyrin and Tb(III) labels in an immunometric immunoassay by time-resolved electrochemiluminescence

  16. Derecho humano al agua y al saneamiento: derechos estrechamente vinculados al derecho a la vida

    OpenAIRE

    Fernández Aller, Maria Celia; Luis Romero, Elena de; Guzmán Acha, Cristina

    2013-01-01

    Los derechos humanos al agua y al saneamiento están íntimamente relacionados con otros derechos esenciales para la vida, como la alimentación o la salud. Su reconocimiento como derechos humanos en 2010 marca un hito importante en el respeto, protección y realización de estos derechos, que se encuentran seriamente vulnerados para una mayoría de población más vulnerable y empobrecida, sobre todo en el ámbito rural. Mucho camino queda aún para conseguir no sólo la disponibilidad de agua y saneam...

  17. Efectividad del uso de alcohol glicerinado para la descontaminación de manos en una población sin aceso al agua potable posterremoto en Pisco, Perú

    Directory of Open Access Journals (Sweden)

    César Cabezas

    2008-10-01

    Full Text Available Se evaluó la efectividad del uso de alcohol glicerinado en la desinfección de manos, de personas que preparaban los alimentos en ollas comunes para damnificados de albergues y comités vecinales sin acceso al agua potable, en los primeros días posteriores al terremoto de Pisco. Se realizó un preexperimento con 20 mujeres adultas que no se habían lavado las manos, se cuantificó la carga bacteriana de aerobios mesófilos, enterobacterias y Staphylococcus aureus en sus manos antes y después de la aplicación de alcohol glicerinado, usando la prueba de Wilcoxon se encontró una reducción significativa (p<0,001 de la carga bacteriana. En conclusión, la aplicación de alcohol glicerinado es efectiva para la desinfección de manos en manipuladores de alimentos en una población sin acceso al agua y posterremoto.

  18. Personalidad y tolerancia al dolor

    Directory of Open Access Journals (Sweden)

    JESÚS M.ª CARRILLO

    2005-01-01

    Full Text Available Se examina la relación de algunas variables de personalidad -EPQ-A (Eysenck y Eysenck, 1975, NEO-PI (McCrae y Costa, 1988 y STA -personalidad esquizotípica- y STB -personalidad límite-, de Claridge y Broks (1984, con la tolerancia al dolor experimental inducido mediante agua fría (cold pressor test, según el procedimiento de Staats, Heckmat y Staats (1998 en una muestra filtrada mediante un cuestionario sobre dolor crónico, dolores de cabeza, de espalda, artritis, síndrome de Raynaud, y personas bajo medicación. La tolerancia al dolor experimental se evaluó mediante el Umbral del dolor (tiempo en segundos desde la introducción de la mano en el agua hasta el primer informe de dolor, Mantenimiento del dolor (duración en segundos de la inmersión de la mano desde la aparición del umbral hasta su retirada y Tolerancia al dolor (duración total en segundos de la inmersión de la mano desde su introducción hasta su retirada. Un análisis correlacional, factorial y de regresión por pasos mostraron un efecto cruzado entre medidas de ansiedad (tolerancia negativa al dolor y psicoticismo, siendo psicoticismo junto con control emocional predictores de tolerancia positiva al dolor. En cuanto a psicoticismo, parece que son sus elementos de naturaleza paranoide y de "dureza" los que afectan a una percepción atenuada del dolor.

  19. 75 FR 62858 - United States, et al.

    Science.gov (United States)

    2010-10-13

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF JUSTICE Antitrust Division United States, et al. v. American Express Company, et al.; Proposed Final Judgment and... of America, et al. v. American Express Company, et al., Civil Action No. CV-10-4496. On October...

  20. 76 FR 38700 - United States, et al.

    Science.gov (United States)

    2011-07-01

    ... published in the Federal Register on October 13, 2010 (75 FR 62858); and (3) published summaries of the... Antitrust Division United States, et al. v. American Express Company, et al.; Public Comments and Response... Final Judgment in United States, et al. v. American Express Company, et al., Civil Action No....

  1. Al/Au/n-Si/Al surface barrier detector

    International Nuclear Information System (INIS)

    Charged-particle detectors are required to be operated sometimes in ambient light for applications like alpha counting and range finding. Detectors like Al/p-Si surface barrier with aluminium on the front side are found quite suitable. Gold/n-Si surface barrier detectors are not usable because of their excessive background photo current. These detectors, we fabricate for use in nuclear experiments, were given an aluminium coating on their gold side for use in room light. The Au/n-Si/Al surface barrier diodes were characterized for their electrical properties and performance as alpha detectors. Detectors showing good energy resolution (∼ 50 KeV) were selected and provided with another thin reflecting coat of aluminium on their front sides

  2. Electrowinning Al from Al2S3 in Molten Salt

    OpenAIRE

    Xiao, Y; Van der Plas, D.W.; Bohte, J.; Lans, S.C.; Van Sandwijk, A.; Reuter, M.A.

    2007-01-01

    In order to investigate an alternative process for the production of primary aluminum via a sulfide intermediate, the electrochemical behavior of Al2S3 in molten salt has been studied on a laboratory scale. The effects of electrolyte composition, temperature, and cell design on the cell performance have been investigated. Temperature and cryolite addition have positive effects on the current density. Increasing the anode-to-cathode surface area (closer to unity) and shortening the interelectr...

  3. Thermal conductance of a pressed Al-Al contact

    Science.gov (United States)

    Wanner, M.

    1981-01-01

    Thermal conductance of a screw-fastened joint between two blocks of Al-alloys has been measured. An AlMg4.5Mn-block, the end of which is cooled by liquid helium, constitutes the upper part of the sample and the contact is formed at the face surface of a cylindrical extension of that block onto which a cylinder, made of AlMgSi1, is pressed by means of a copper-nickel screw. Pressing of the contact was carried out at room temperature by applying a defined torque, M, to the fastening screw. Three samples of the same shape but with differently treated surfaces of contact (machined flat, electro-chemically polished, with gold plated contacts) were studied. The results showed that the machined flat surfaces yield the best contact and that the contact conductance (measured in the range 4.2 K to 1.8 K) of all samples increased with increasing torque. In addition to thermal measurements, a study of the electrical conductance would be very interesting to determine the different contributions of phonon and electron heat conduction by means of the Wiedemann-Franz law. The work is useful for the GIRL (German Infra-Red Laboratory) space experiment.

  4. Caffeine degradation by Rhizopus delemar in packed bed column bioreactor using coffee husk as substrate Degradação de cafeína por Rhizopus delemar em biorreator de colunas usando casca de café como substrato

    Directory of Open Access Journals (Sweden)

    Cristiane Vanessa Tagliari

    2003-11-01

    Full Text Available Various microorganisms including bacteria, yeast and fungi can degrade caffeine. There are few publications about caffeine degradation pathway in filamentous fungi, mainly by solid-state fermentation (SSF. Studies were carried out on degradation of caffeine and their metabolites by filamentous fungi in SSF using coffee husk as substrate. The purpose of this work was to investigate the caffeine degradation pathway by Rhizopus delemar in packed bed column fermenter and to compare this degradation metabolism with glass flasks fermentation. The methylxanthines were quantified by HPLC analysis. The experiments were realized with the optimized conditions in previous experiments: pH 6.5, 28ºC, inoculation rate 10(6 spores/g substrate, aeration rate 60 mL/min and initial moisture 73%. Under these conditions, after 72 hous of fermentation was achieved only 0.19% of caffeine and 0.014% of theophylline in the coffee husk. The strain proved to be able for caffeine and theophylline degradation by SSF in packed bed column bioreactor.Diversos microrganismos incluindo bactérias, fungos e leveduras são capazes de assimilar a cafeína de meios sintéticos ou de resíduos de café. Existem poucos trabalhos sobre a via de degradação da cafeína em fungos filamentosos, principalmente por fermentação no estado sólido (FES. Estudos de degradação da cafeína por fungos filamentosos em FES usando casca de café como substrato vêm sendo realizados. O objetivo deste trabalho foi investigar a via de degradação da cafeína por Rhizopus delemar em biorreator de colunas aeradas e comparar este metabolismo de degradação com o da fermentação em frascos de vidro. As metilxantinas foram quantificadas por análises em HPLC. Os experimentos foram realizados com as condições otimizadas previamente: pH 6,5, 28ºC, 10(6 espores/g substrato, vazão de ar 60 mL/min e 73% de umidade inicial. Após 90 horas de fermentação, 65% da cafeína foi reduzida, resultando 0

  5. Lesão brônquica e pneumotórax após reintubação usando um cateter para troca da via aérea

    Directory of Open Access Journals (Sweden)

    Juliano P. de Almeida

    2013-02-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: Relatamos um caso de pneumotórax causado por perfuração brônquica durante uma reintubação usando um cateter para troca da via aérea (CTVA em um paciente com câncer de cabeça e pescoço. RELATO DE CASO: Paciente do sexo masculino, 53 anos, com carcinoma de orofaringe, foi internado na UTI com pneumonia grave e síndrome da angústia respiratória aguda (SARA. O paciente foi identificado como sendo de difícil intubação e uma sonda endotraqueal (SET foi inserida através de um broncoscópio. Após uma semana de tratamento, observou-se ruptura do manguito endotraqueal. A troca da sonda endotraqueal foi necessária para obter uma ventilação pulmonar satisfatória. Um cateter para troca da via aérea (Cook, tamanho 14 foi usado para realizar a reintubação. Depois da reintubação, o paciente apresentou piora na saturação de oxigênio e uma radiografia revelou um grande pneumotórax. Um dreno torácico foi inserido e uma melhora imediata na saturação de oxigênio foi observada. A repetição da radiografia confirmou o posicionamento correto do dreno torácico e a reexpansão do pulmão direito. A broncoscopia realizada mostrou uma laceração posterior do brônquio principal direito. O paciente foi extubado no dia seguinte. Depois de quatro dias, o dreno torácico foi removido. A radiografia realizada um dia depois da retirada do dreno revelou um pequeno pneumotórax no lobo superior direito, mas o paciente permaneceu assintomático. CONCLUSÕES: O cateter para troca da via aérea é uma ferramenta valiosa para lidar com pacientes difíceis de intubar. Embora os médicos geralmente concentrem sua atenção em evitar um barotrauma causado pelo suplemento de oxigênio ou ventilação a jato através do CTVA, a preocupação com a técnica de inserção pode minimizar as complicações que ameaçam a vida e aumentar a segurança do CTVA.

  6. Estimativa das condições de conforto térmico para avicultura de postura usando a teoria dos conjuntos Fuzzy Estimated thermal comfort condition for layers according to Fuzzy theory

    Directory of Open Access Journals (Sweden)

    Henrique L. de Oliveira

    2005-08-01

    Full Text Available Neste trabalho, foi utilizada uma ferramenta matemática promissora na análise de sistemas e/ou processos, particularmente na área de produção animal. Essa ferramenta é a desenvolvida segundo a abordagem da teoria dos Conjuntos Fuzzy e, neste caso específico, permitiu a análise da composição das variáveis climáticas independentes, como temperatura de bulbo seco e umidade relativa do ar, que influenciam na variável dependente denominada conforto térmico das aves. Foi realizada a construção de regras baseadas na intuição humana, segundo o conhecimento de especialistas da área, a partir do que é possível simular cenários distintos para o suporte à decisão de construção de galpões para abrigo a animais. Neste trabalho, foi estimado o conforto térmico para alojamento de aves poedeiras em produção. Os resultados foram analisados, usando-se o ambiente de computação científica MATLAB 6.5, o que pode ser realizado iterativamente a cada cenário gerado. Com base nos resultados obtidos, pode-se analisar as condições de conforto para distintas composições das variáveis de entrada.In this research a promising mathematical tool in system's analysis and/or process particularly in the area of Animal Production was used. Such tool was developed according to Fuzzy theory which in this specific case allows analyzing the composition of independent climatic variables, such as temperature and humidity that may influence the dependent variable named bird's thermal comfort. It was necessary to build up rules based on human intuition according to experts in this area, from which was possible to simulate distinct scenarios for supporting the decision of the construction of animal's housing. In this research thermal comfort for layer's housing in production were considered. The results were analyzed using the scientific computer environment of MATLAB 6.5, which could be done iteratively for each generated scenario. Based on the results

  7. Secagem do Polissacarídeo l-Carragena Usando um Leito de Jorro Fluidizado Bidimensional Drying of l-Carrageenan Using a Two Dimensional Spouted Fluidized Bed Dryer

    Directory of Open Access Journals (Sweden)

    Héctor José Ciro Velásquez

    2012-06-01

    Full Text Available Resumo. Suspensões de l-carragena foram secas usando um secador de leito de jorro fluidizado bidimensional com partículas inertesplásticas de ABS (acrilonitrilo-butadieno-estireno. O desempenho do secador (produção de pó e retenção de sólidos e qualidade do produto seco obtido (propriedades reológicas e teor de umidade foi avaliado. Os resultados mostraram que a eficiência de produção média de pó foi de 23% com uma retenção média de 71%. A variável mais relevante na secagem das suspensões foi a vazão de alimentação, sendo que um aumento desta variável produziu um baixo rendimento de pó e aumentou a retenção de sólidos dentro do leito. O produto reconstituído de l-carragena obtido nas condições otimizadas de secagem formou suspensões de natureza altamente pseudoplástica, porém com propriedades viscoelásticas características de suspensões altamente diluídas (G''>G', mostrando valores de viscosidade, módulos elástico (G' e de perda (G'' menores que o produto comercial.Abstract. l-carrageenan suspensions were dried using a two dimensional spouted fluidized bed dryer with inert particles of ABS (acrylonitrile butadine styrene. The dryer performance (powder production and solid retention and quality properties of final product (rheological properties and moisture content were evaluated. According to results the mean powder production of l-carrageenan using ABS as inert particle was of 23% with a solid retention of 71%. The most significant variable in the drying of suspension was the feed mass flow rate, as its increase produced a diminishing of the powder production and increasing of the solids retention in the bed. The reconstituted suspensions of l-carrageenan obtained from optimized conditions of drying formed highly pseudoplastic suspensions with viscoelastic properties of highly diluted (G''>G' systems. In addition, the rheological characteristics as viscosity, storage (G' and loss moduli (G'' were lower

  8. Utilização do AutoCAD 2004 para quantificação de pesquisas usando fotomicrografias eletrônicas AutoCAD 2004 to quantify electron-photomicrography

    Directory of Open Access Journals (Sweden)

    Carla Albertina Martins Almeida

    2007-08-01

    Full Text Available OBJETIVO: Avaliar o uso do programa AutoCAD 2004 para estudos quantitativos em microscopia eletrônica. MÉTODOS: A demonstração da utilização do AutoCAD 2004 foi feita em um modelo experimental de diabetes induzido em ratos, divididos em Grupo Controle (GC-10 animais e Grupo Diabético (GD - 10 animais, avaliados 1 mês depois da indução do diabetes. Os olhos foram removidos após o sacrifício dos animais e preparados para exame em microscópio eletrônico, tendo sido feitas fotografias dos vasos retinianos. Foi utilizado o programa AutoCAD2004 para avaliar a espessura da membrana basal dos vasos. Os resultados foram avaliados estatisticamente. RESULTADOS: Usando o método proposto foi possível realizar medidas quantitativas na membrana basal de vasos retinianos de ratos diabéticos. CONCLUSÃO: O AutoCAD 2004 se mostrou efetivo, seguro e de fácil utilização para a quantificação de fenômenos biológicos, sendo possível sugerir este meio para a realização de avaliações quantitativas em experimentos biológicos.OBJECTIVE: To determine if the AutoCAD 2004 program is available to be used in quantitative research on electron microscopy. METHODS: A demonstrative of the AutoCAD2004 was done in an experimental model of diabetes induced in rats. The animals were divided by lot in control group animals (GC-10 animals and diabetic group (GD - 10 animals, evaluated 1 month after the diabetes induction. The eyes were removed after sacrifice and prepared to electron microscopy. The retina was photographed and the AutoCAD2004 program was used to measure the basal membrane of retina vessels. The results were submitted to statistical analysis. RESULTS: The AutoCAD2004 was effective to obtain quantitative measures from the basal membrane of retina vessels and there were no difference between the studied groups. CONCLUSION: The AutoCAD2004 was effective, safe and easy to apply to quantify biological parameters, which allowed suggest it to

  9. Sinterização ultra-rápida de materiais cerâmicos usando radiação laser Ultra-fast laser sintering of ceramic materials

    Directory of Open Access Journals (Sweden)

    Z. S. Macedo

    2000-12-01

    Full Text Available Nessa comunicação apresentamos nossos primeiros resultados de sinterização ultra-rápida em materiais cerâmicos óxidos usando a radiação de um laser de CO2 como fonte de aquecimento. Os compostos Bi4Ti3O12 (BIT e Bi4Ge3O12 (BGO foram sintetizados via reação do estado sólido, conformados em corpos cerâmicos cilíndricos de 12 mm de diâmetro e 2 mm de espessura e, posteriormente, levados ao laser para o processo de sinterização. A análise dos pós reagidos, efetuada por difratometria de raios X, confirmou a presença de fase cristalina única em cada um dos sistemas investigados. A potência máxima do laser necessária para a sinterização apresentou forte dependência com a estratégia usada na irradiação. A análise da microestrutura, realizada por microscopia eletrônica de varredura (MEV, revelou um alto grau de eficiência do processo desenvolvido. Em alguns casos, pudemos verificar que a sinterização ocorreu a uma profundidade de até 1 mm, apontando para a viabilidade de obtenção de corpos cerâmicos sinterizados como um todo.In this communication we present our first results on ultra-fast laser sintering of oxide ceramics employing a CO2 laser as the heating source. The Bi4Ti3O12 (BIT and Bi4Ge3O12 (BGO compounds were synthesized following a solid state route in air atmosphere. Cylindrical ceramic bodies with 12 mm in diameter and 2 mm in thickness were shaped and sintered under laser irradiation. The X-ray diffraction of the calcined powders confirmed the presence of single phase in each of the investigated systems. The maximum laser power required to the sintering process showed to have a strong dependency on the strategy used for irradiation. The microstructure analysis of the samples, performed by scanning electron microscopy (SEM, revealed the high efficiency of the process. In some cases we could verify that the sintering occurred until a depth of 1mm, indicating the feasibility of obtaining the ceramic bodies

  10. Type idéal

    OpenAIRE

    Paugam, Serge

    2014-01-01

    L’usage de types idéaux constitue pour Max Weber une démarche sociologique fondamentale. Le type idéal est pour lui un moyen de comprendre le sens que les individus donnent à leurs expériences vécues, ce qui conduit à mettre ces dernières en relation avec l’organisation de la société à un moment historique de son évolution. Définir un type idéal ne signifie pas repérer sa forme majoritaire d’un point de vue statistique, mais discerner à partir des formes historiques des sociétés contemporaine...

  11. Al-Hadith Text Classifier

    Directory of Open Access Journals (Sweden)

    Mohammed Naji Al-Kabi

    2005-01-01

    Full Text Available This study explore the implementation of a text classification method to classify the prophet Mohammed (PBUH hadiths (sayings using Sahih Al-Bukhari classification. The sayings explain the Holy Qur`an, which considered by Muslims to be the direct word of Allah. Present method adopts TF/IDF (Term Frequency-Inverse Document Frequency which is used usually for text search. TF/IDF was used for term weighting, in which document weights for the selected terms are computed, to classify non-vocalized sayings, after their terms (keywords have been transformed to the corresponding canonical form (i.e., roots, to one of eight Books (classes, according to Al-Bukhari classification. A term would have a higher weight if it were a good descriptor for a particular book, i.e., it appears frequently in the book but is infrequent in the entire corpus.

  12. The effect of Si in Al-alloy on electromigration performance in Al filled vias

    Science.gov (United States)

    Kageyama, Makiko; Hashimoto, Keiichi; Onoda, Hiroshi

    1998-01-01

    Electromigration performance of vias filled with Al-Si-Cu alloys on Ti glue layers was investigated in comparison with W-stud vias. In Al-Si-Cu filled vias, voids were formed at only a few locations in the test structure, while voids were formed at every via in W-stud via chains. It is supposed that Al moves through the Al-Si-Cu via during electromigration in spite of the existence of a glue layer at the via bottom. This phenomenon was observed only in the vias filled with Al-Si-Cu alloy. Al movement was prohibited in Al-Cu filled vias. In Al-Si-Cu filled vias, an Al-Ti-Si alloy was formed at the via bottom while Al3Ti was formed at Al-Cu filled vias. Al is speculated to move through this Al-Ti-Si alloy during electromigration.

  13. Lernhabitus als Grundlage lebenslanger Lernprozesse

    OpenAIRE

    Herzberg, Heidrun

    2005-01-01

    'In diesem Artikel wird die These vertreten, dass das Habitus-Konzept von Bourdieu, wenn es bei der Analyse von lebenslangen (biographischen) Lern- und Bildungsprozessen angewandt wird, einer biographietheoretischen Reformulierung bedarf. Vor diesem Hintergrund wird das eigene Konzept des biographischen Lernhabitus vorgestellt. Als Ergebnis einer Zwei-Generationen-Studie im Rostocker Werftarbeitermilieu können zwei deutlich voneinander zu entscheidende Lernhabitusmuster präsentiert werden. In...

  14. Utilitarismus als Methode der Ethik

    OpenAIRE

    Daniels, Malte Cornelius

    2011-01-01

    In diesem Buch schlage ich eine radikal neuartige Sicht auf den Utilitarismus vor. Meine Hauptthese ist, dass der Utilitarismus selbst keine vollständige normative Theorie ist, aus der sich per se Handlungsbewertungen ableiten ließen, sondern normativ untersättigt und neutral ist. Sein normativer Gehalt ist vollständig abhängig von angenommenen Nutzenfunktionen. Jede konsistente Menge von moralischen Regeln (Moralsystem) kann, wie ich im Anhang beweise, als ein Spezialfall des Utilitarismus i...

  15. Vormundschaftsrecht als Grundlage politischer Herrschaft

    Directory of Open Access Journals (Sweden)

    Arne Duncker

    2006-07-01

    Full Text Available In ihrer beachtlichen und sehr gewissenhaft dokumentierten Arbeit über vormundschaftliche Regentschaften im 16. und 17. Jahrhundert beschreibt Pauline Puppel unter ausführlichem Bezug auf zeitgenössische Literatur und Archivalien sowohl die allgemeine Rechtslage im damaligen Reich als auch die Anwendungsfälle in Hessen, wo zwischen 1500 und 1700 insgesamt viermal eine Landgräfin als Vormünderin des Fürsten zur Regentin ihres Landes wurde. Dies steht exemplarisch für eine bereits in der Frühen Neuzeit mögliche und nicht einmal ganz seltene Form politischer Frauenherrschaft, die bisher oft nicht hinreichend gewürdigt wurde. Puppels Untersuchung ist in zwei Hauptteile gegliedert. Der erste Teil (Das juristische Regelwerk“, S. 34-143 behandelt die zeitgenössischen Rahmenbedingungen der durch Frauen ausgeübten Vormundschaft und Regentschaft. Der zweite Abschnitt („Die Landgräfinnen von Hessen als Regentinnen“, S. 144-307 befasst sich mit der Ausfüllung dieser Regeln durch konkrete Fallbeispiele in Gestalt von Leben und Regentschaft der regierenden Landgräfinnen von Hessen.

  16. Microstructure of interaction interface between Al-Si, Zn-Al alloys and Al2O3p/6061Al composite

    Institute of Scientific and Technical Information of China (English)

    许志武; 闫久春; 吕世雄; 杨士勤

    2004-01-01

    Interaction behaviors between Al-Si, Zn-AI alloys and Al2O3p/6061AI composite at different heating temperatures were investigated. It is found that Al2O3p/6061Al composite can be wetted well by AlSi-1, AlSi-4 and Zn-Al alloys and an interaction layer forms between the alloy and composite during interaction. Little Al-Si alloys remain on the surface when they fully wet the composite and Si element in Al-Si alloy diffuses into composite entirely and assembles in the composite near the interface of Al-Si alloy/composite to form a Si-rich zone. The microstructure in interaction layer with Si penetration is still dense. Much more residual Zn-Al alloy exists on the surface of composite when it wets the composite, and porosities appear at the interface of Zn-Al alloy/composite. The penetration of elements Zn, Cu of Zn-Al alloy into composite leads to the generation of shrinkage cavities in the interaction layer and makes the microstructure of Al2 O3p/6061A1 composite loose.

  17. The Structure and Main Issues of “al-Tasdid” of Husam al-Din al-Syghnaqi

    Directory of Open Access Journals (Sweden)

    Daniyar B. Shalkarov

    2015-07-01

    Full Text Available The study of the theological maturidia in the Central Asia was developed by the majority of outstanding scientists in the Turkic area and was known from generation to generation with manuscripts. One of these famous scientists was Abu al-Mu‘in al-Nasafi. In Central Asia, in the branch of the Islamic kalam theology there were the works “Tabsira al-Adilla”, “Bahr al-Kalam”, “al-Tamheed li qawa‘id al-Tawheed”, which considered the issues of maturidia theological study. In the XIV century the great scientist from Syghanaq Husam al-din al-Syghnaqi made a detailed research of the work “al-Tamheed li qawa‘id al-Tawheed” of Abu al-Mu‘in al-Nasafi and wrote the work “al-Tasdeed fi sharh al-Tamheed” by giving a full explanation of all questions relating to the issue. This article considers the content and the kept versions in the World libraries and the importance of this work for today. There is a different information about the original version of the manuscript. The first, the manuscript is by Amca Zade Huseyn 309 number, written by Husam al-din al-Syghnaqi personally and kept in the turkic library. This information is written in the work “Syghanaq Sanlagi/ The star of the Syghanaq” of Shamshaddin Kerim, the second manuscript is kept in the Egypt Arabic Republic, in the library “Dar al-Kutub Misrya”. It is written in this manuscript, that the manuscript was published in 1125 according hizhra calendar. Therefore the article gives an explanation of the main maturidia kalam principles, which cover five chapters of the work. 

  18. Armaflex in Burj al Arab; Armaflex im Burj al Arab

    Energy Technology Data Exchange (ETDEWEB)

    Steiner, B.

    2003-07-01

    This article describes the Burj al Arab in Dubai, the unique seven-star high-rise hotel. The construction of the hotel, that is built on 250 piles driven into the sand of an artificial island in the Persian Gulf, is described. In particular, various special materials used in the building are described, as are the luxurious fittings and furnishings of the hotel. The cooling and air-conditioning installations that are necessary as a result of the desert climate of Dubai are described and the use of 'Armaflex' elastomer insulating material for the insulation of refrigeration machines and cold-water piping is discussed.

  19. De los derechos humanos al derecho al aborto

    OpenAIRE

    Zúñiga Fajuri, Alejandra

    2013-01-01

    Ninguna otra persona, en ninguna situación, es obligada a realizar el acto supererogatorio que se exige a la mujer embarazada. Aun cuando una adecuada aplicación de la teoría general de los derechos humanos permite reconocer el derecho al aborto durante los dos primeros trimestres del embarazo sobre la base de que los derechos sólo pueden restringirse por mor de los propios derechos. En esa línea, se intenta responder a quienes sostienen que el problema del aborto no puede resolverse pues no ...

  20. Friction Stir Welding of Al 5052 with Al 6061 Alloys

    OpenAIRE

    Kumbhar, N. T.; Bhanumurthy, K.

    2012-01-01

    Friction stir welding (FSW), a solid-state joining technique, is being extensively used in similar as well as dissimilar joining of Al, Mg, Cu, Ti, and their alloys. In the present study, friction stir welding of two aluminium alloys—AA6061 and AA5052—was carried out at various combinations of tool rotation speeds and tool traverse speeds. The transverse cross-section of the weld was used for optical as well as electron microscopy observations. The microstructural studies were used to get an ...

  1. Memahami Tasawuf Ibnuu Arabi dan Ibnuu al Farid: Konsep al Hubb Illahi, Wahdat al Wujud, Wahdah al Syuhud dan Wahdat al Adyan

    Directory of Open Access Journals (Sweden)

    Muhammad Robith Fuadi

    2013-12-01

    Full Text Available Kaum sufi menapaki jalan yang berbeda untuk menuju hakikat, mereka tidak menggunakan akal dan rasio untuk sampai pada hakikat. Akan tetapi, akal bukan satu-satunya jalan untuk menuju hakikat. Karena kita sering melihat sesuatu yang di luar jangkauan akal dalam hidup ini. Jalan yang ditempuh kaum sufi untuk menuju hakikat seperti kasyf, dzauq, 'iyan, musyahadah dan sebagainya dinilai sebagai sesuatu yang samar, tidak mempunyai batasan dan kaidah pasti, bahkan sering kali bercampur dengan igauan, mimpi, khayalan dan angan-angan. Tapi yang perlu kita ingat adalah bahwa media-media tersebut telah mampu menuntun manusia untuk memecahkan sesuatu yang tidak bisa dipecahkan oleh akal dan hukum-hukum fisika. Tulisan ini akan mengkaji gagasan-gagasan dua tokoh tasawuf besar yaitu Ibnu Arabi dan Ibnu al-Farid yang hidup  pada abad keenam dan ketujuh Hijriah. Tulisan ini secara spesifik akan mengkaji tiga gagasan penting ke dua tokoh tersebut. Yaitu al hubb al Ilahi, wahdat al Wujud dan wahdat al adyan.

  2. POS-Tagging usando pesquisa local

    OpenAIRE

    Laranjinho, João; Rodrigues, Irene; Ferreira, Lígia

    2013-01-01

    Neste artigo apresenta-se um sistema de part-of-speech tagging, independente do domínio, para etiquetação gramatical de texto para o Português e Inglês. O etiquetador usa informação morfo-sintáctica que vem de um dicionário local que completa a sua informação recorrendo a dicionários disponíveis na rede como o da Priberam e do LookWayUP. Este etiquetador é baseado numa função heurística que é usada na optimização dos seus parâmetros e posterior etiquetação de texto. Na optimização d...

  3. Campimetría usando realidad virtual

    Directory of Open Access Journals (Sweden)

    Juan Posada

    2001-04-01

    Full Text Available

    La campimetría es de gran utilidad en el diagnóstico y seguimiento
    de enfermedades retinianas y ha evolucionado de los métodos
    manuales a las modernas técnicas automatizadas. Los objetivos principales son: diseñar, desarrollar y validar un programa en realidad virtural (RV para la realización de campimetrías, desarrollar una página WEB para presentación de avances del proyecto y crear una línea de investigación para el desarrollo de otras aplicaciones médicas con RV.

     

     

  4. Juego de rol usando RPG Maker

    OpenAIRE

    Tregon Muniesa, Adrià

    2009-01-01

    En la documentación del proyecto encontramos una introducción a los videojuegos, explicación del rol y sus características más relevantes, y una pincelada sobre el mercado actual de la industria española del videojuego.Los objetivos a alcanzar en la realización del proyecto. Explicación de la historia, de los personajes con sus respectivas estadísticas y un storyboard completo del juego. Explicación de las características más relevantes de RPG Maker VX, así como un diagrama de las clase...

  5. Criptografia usando curvas hiperelípticas

    Directory of Open Access Journals (Sweden)

    Alonso Sepúlveda Castellanos

    2006-01-01

    Full Text Available In this work we present some properties of the hyperelliptical curves and their Jacobians, aiming at the implementation of criptossystems of public key. Also we show the algorithm of Cantor to add points in the Jacobian manifold, which is important for the effectiveness of criptossystems, and an algorithm to attack the problem of the discrete logarithms on these groups. The untractability of this problem is essential for the security of criptossystems.

  6. The Eminent Turkish Logician al-Abhari and "al-Risalah fî al-Kavâid al-Mantıqiyyah"

    OpenAIRE

    el-EBHERÎ, Esîrüddîn Mufaddal b. Ömer es-Semerkandî

    2014-01-01

    Athar al-Din al-Abhari is an important figure whose works had been textbooks in the Ottoman schools for centuries al-Abhari who wrote so many books in such areas as philosophy, mathematics, astronomy and logic is especially known for his books Hidayat al-Hikmat and İsaghuji He took logic into account in all of his works of philosophy. He also wrote some books and treatises specially concerning logical problems. Here, we are going to present the Turkish translation of his al-Risâlah fi al-Kava...

  7. United modification of Al-24Si alloy by Al-P and Al-Ti-C master alloys

    Institute of Scientific and Technical Information of China (English)

    韩延峰; 刘相法; 王海梅; 王振卿; 边秀房; 张均艳

    2003-01-01

    The modification effect of a new type of Al-P master alloy on Al-24Si alloys was investigated. It is foundthat excellent modification effect can be obtained by the addition of this new type of A1-P master alloy into Al-24Simelt and the average primary Si grain size is decreased below 47 μm from original 225 μm. It is also found that theTiC particles in the melt coming from Al8Ti2C can improve the modification effect of the Al-P master alloy. Whenthe content of TiC particles in the Al-24Si melt is 0.03 %, the improvement reaches the maximum and keeps steadywith increasing content of TiC particles. Modification effect occurs at 50 min after the addition of the Al-P master al-loy and TiC particles, and keeps stable with prolonging holding time.

  8. Diseño y simulación de la implementación de tecnologías y procedimientos de transición del protocolo IPv6 en INTRANETS usando un IPv6 test bed

    OpenAIRE

    Mercado, Gustavo; Taffernaberry, Juan Carlos; Dantiacq, Alejandro; Pérez, Santiago; Moralejo, Raúl O.

    2007-01-01

    El Protocolo de Internet actual, conocido como IPv4, comienza a dar señales de encontrarse al límite de su diseño y ya no puede seguir brindando respuestas adecuadas [1]. El Internet Enginering Task Force (IETF) desarrolló un nuevo protocolo de Internet, denominado IPv6 que reemplazará al antiguo [2]. Una de las tareas fundamentales es la transición del viejo protocolo al nuevo IPv6 [3]. Esta afirmación define un conjunto de mecanismos y procedimientos que las redes de Internet deben imple...

  9. The Al-Al3Ni Eutectic Reaction: Crystallography and Mechanism of Formation

    Science.gov (United States)

    Fan, Yangyang; Makhlouf, Makhlouf M.

    2015-09-01

    The characteristics of the Al-Al3Ni eutectic structure are examined with emphasis on its morphology and crystallography. Based on these examinations, the mechanism of formation of this technologically important eutectic is postulated. It is found that a thin shell of α-Al forms coherently around each Al3Ni fiber. The excellent thermal stability of the Al-Al3Ni eutectic may be attributed to the presence of this coherent layer.

  10. Filtros digitales de tangente hiperbólica aplicados al alisado de las perturbaciones en los datos de resistividad de fosfato de Marruecos

    Directory of Open Access Journals (Sweden)

    M. Amrani

    2008-06-01

    Full Text Available Es posible diseñar filtros pasa bajos y pasa bandas por medio de una combinación de funciones tangente hiperbólica en el dominio de la frecuencia, usando los teoremas de escalamiento y deslizamiento de las transformadas de Fourier. Las funciones de filtro correspondientes en el dominio del tiempo pueden ser derivadas analíticamente a partir de las expresiones en el dominio de la frecuencia. Los parámetros de suavidad controlan las pendientes en las regiones de corte y permiten la construcción de filtros relativamente pequeños al mismo tiempo que reducen las oscilaciones de la respuesta del filtro en el dominio del tiempo. Se pueden elegir diferentes parámetros de suavidad para las frecuencias de corte alta y baja en el diseño de filtros pasa banda. Siguiendo el esquema propuesto en este artículo se pueden derivar fácilmente los otros tipos de filtro.

  11. Reply to Pachai et al.

    Science.gov (United States)

    Harrison, William J; Bex, Peter J

    2016-05-01

    Peripheral vision is fundamentally limited by the spacing between objects. When asked to report a target's identity, observers make erroneous reports that sometimes match the identity of a nearby distractor and sometimes match a combination of target and distractor features. The classification of these errors has previously been used to support competing 'substitution' [1] or 'averaging' [2] models of the phenomenon known as 'visual crowding'. We recently proposed a single model in which both classes of error occur because observers make their reports by sampling from a biologically-plausible population of weighted responses within a region of space around the target [3]. It is critical to note that there is no probabilistic substitution or averaging process in our model; instead, we argue that neither substitution nor averaging occur, but that these are misclassifications of the distribution of reports that emerge when a population response distribution is sampled. This is a fundamentally different way of thinking about crowding, and on this basis we claim to have provided a mechanism unifying categorically distinct perceptual errors. Our goal was not to model all crowding phenomena, such as the release from crowding when target and flanks differ in color or depth [4]. Pachai et al.[5] have suggested that our model is not unifying because it inaccurately predicts perceptual performance for a particular stimulus. Although we agree that our model does not predict their data, this specific demonstration overlooks the critical aspect of the model: perceptual reports are drawn from a weighted population code. We show that Pachai et al.'s [5] own data actually provide evidence for the population code we have described [3], and we suggest a biologically-plausible analysis of their stimuli that provides a computational basis for their 'grouping' account of crowding. PMID:27166690

  12. Al-Hadith Text Classifier

    OpenAIRE

    Mohammed Naji Al-Kabi; Ghassan Kanaan; Riyad Al-Shalabi; Saja I. Al- Sinjilawi; Ronza S. Al- Mustafa

    2005-01-01

    This study explore the implementation of a text classification method to classify the prophet Mohammed (PBUH) hadiths (sayings) using Sahih Al-Bukhari classification. The sayings explain the Holy Qur`an, which considered by Muslims to be the direct word of Allah. Present method adopts TF/IDF (Term Frequency-Inverse Document Frequency) which is used usually for text search. TF/IDF was used for term weighting, in which document weights for the selected terms are computed, to classify non-vocali...

  13. The ALS Gun Electronics system

    International Nuclear Information System (INIS)

    The ALS Gun Electronics system has been designed to accommodate gun with a custom made socket and high speed electronics circuit which is capable of producing single and multiple electron bunches with time jitters measured at better than 50 PS. The system generates the gated RF signal at ground level before sending it up to the 120 KV-biased gun deck via a fiber optic cable. The current pulse width as a function of grid bias, using an Eimac 8847A planar triode simulating an electron gun, was measured to show the relationship between the two parameters

  14. The ALS project: lessons learned

    Science.gov (United States)

    Monckton, Simon; Collier, Jack; Giesbrecht, Jared; Broten, Greg; MacKay, David; Erickson, David; Verret, Sean; Digney, Bruce

    2006-05-01

    In support of Canadian Forces transformation, Defence R&D Canada (DRDC) has established an ongoing program to develop machine intelligence for semi-autonomous vehicles and systems. Focussing on mine clearance and remote scouting for over a decade, DRDC Suffield has developed numerous UGVs controlled remotely over point-to-point radio links. Though this strategy removes personnel from potential danger, DRDC recognized that human factors and communications bandwidth limit teleoperation and that only networked, autonomous unmanned systems can conserve these valuable resources. This paper describes the outcome of the first autonomy project, Autonomous Land Systems (ALS), designed to demonstrate basic autonomous multivehicle land capabilities.

  15. Analisis Salasilah Tarekat Shaykh Shams al-Din al-Sumatra’i

    OpenAIRE

    ROHAIMI RASTAM; MOHD SYUKRI YEOH ABDULLAH; YUSRI MOHAMAD RAMLI

    2015-01-01

    This article examines the spiritual chain (silsilah tariqah) of Shaykh Shams al-Din al-Sumatra’i (alt. al-Sumatrani), Qadi al-Malik al-‘Adil (Prime Minister and Mufti) of Aceh during the reign of Sultan Iskandar Muda in 1607 to 1627. The study is primarily based on his manuscript of Mir’at al-Muhaqqiqin as well as Shaykh Abdul Haqq Muhaddith Dahlawi’s Zad al-Muttaqin. By mapping the lineage of all data available, this study features al-Sumatra’is spiritual chain that consist of Qadiriyyah, Sh...

  16. Grainreifnementlimit of commercialpureAl inoculatedbyAl-Ti-C(B)masteralloys

    Institute of Scientific and Technical Information of China (English)

    En-zhao Wang; Xiang-fa Liu

    2015-01-01

    The grain reifnement limits of commercial pure Al inoculated by Al-5Ti-1B, Al-5Ti-0.25C and Al-5Ti-0.3C-0.2B master al oys were studied, and the inlfuence of melting temperature on the grain reifning performance of these three master al oys was investigated using a high scope video microscope (HSVM), a ifeld-emission scanning electron microscope (FESEM), an electron probe micro-analyzer (EPMA) and X–ray diffraction (XRD) method. Results show that there is a grain reifnement limit of commercial pure Al reifned by these three master al oys; with the same addition level of 1.5% under the present experimental conditions, the grain reifnement limits (smal est average grain size) of commercial pure Al reifned by Al-5Ti-1B, Al-5Ti-0.25C and Al-5Ti-0.3C-0.2B master al oys are 50 µm, 80 µm and 80 µm, respectively. In addition, with an increase in the melting temperature of the pure Al, the grain reifning performance of Al-5Ti-1B and Al-5Ti-0.25C master al oys decreases, but the grain reifning performance of Al-5Ti-0.3C-0.2B changes little.

  17. Formaline of alternatieven als ontsmettingsmiddel voor broedeieren

    OpenAIRE

    Meijerhof, R.; Dijk, D. van

    1997-01-01

    Formaline wordt algemeen gezien als een goed middel om broedeieren te ontsmetten. Toch geeft ontsmetting met middelen als ozon en waterstofperoxyde vaak een iets beter broedresultaat. Een eventuele verklaring hiervoor is momenteel nog niet te geven.

  18. Benefits for Military Veterans with ALS

    Science.gov (United States)

    ... Chapters Certified Centers and Clinics Support Groups About ALS About Us Our Research In Your Community Advocate ... Veterans Resources for Military Veterans, Families & Survivors The ALS Association is working everyday to support people with ...

  19. Uso de probióticos na rinite alérgica Probiotics in allergic rhinitis

    Directory of Open Access Journals (Sweden)

    Janaina Cândida Rodrigues Nogueira

    2011-02-01

    Full Text Available Probióticos são microrganismos viáveis, usados como suplemento alimentar, normalmente bactérias ácidas lácticas, que podem modificar a composição e/ou a atividade metabólica da microbiota intestinal, modulando o sistema imune de forma que beneficie a saúde do indivíduo. OBJETIVO: Fazer uma revisão sobre o uso de Probióticos (Lactobacillus e Bifidobacterium na rinite alérgica. MATERIAL E MÉTODO: Foram pesquisados artigos originais no Pubmed. RESULTADOS: Os resultados encontrados indicam que os probióticos, Lactobacillus e Bifidobacterium parecem prevenir as recorrências alérgicas, aliviar a severidade dos sintomas e promover melhora da qualidade de vida dos pacientes com rinite alérgica. Estes efeitos ocorrem devido à modulação do sistema imunológico através da indução da produção de citocinas que promovem uma resposta TH1 dominante em alérgicos, através do efeito da modulação no balanço TH1/TH2. CONCLUSÃO: O uso de bactérias probióticas pode ser uma forma efetiva e segura de prevenção e/ou tratamento de rinite alérgica, mas seu mecanismo exato de ação permanece desconhecido. No entanto, estudos clínicos usando probióticos e intervenção dietética deverão ser o foco de futuras investigações, para permitir um uso mais amplo.Probiotics are live microorganisms used as supplementary food, usually lactic acid bacteria that can change either the composition and/or the metabolic activities of the gut microbiota modulating the immune system in a way that benefits the person's health. AIM: To review the use of Probiotics (Lactobacillus and Bifidobacterium in allergic rhinitis patients. MATERIALS AND METHODS: Pubmed original articles were used as data source. RESULTS: Results indicate that probiotics, Lactobacillus and Bifidobacterium appear to prevent allergy recurrences, alleviate the severity of symptoms and improve the quality of life of patients with allergic rhinitis. This happens because of the immune

  20. AlON-SiAlON复合材料的制备及特性%Preparation and properties of AlON-SiAlON composites

    Institute of Scientific and Technical Information of China (English)

    山下敬; 山口明良

    2003-01-01

    为提高AlON陶瓷材料的抗氧化性能,制备了AlON-SiAl7O2N7复相材料.在1750℃、0.5 MPa的N2气氛中,保温2 h烧成不同Al2O3/AlN/Si3N4配比的原料得到不同AlON/SiAl7O2N7比的复相材料.因为在烧结SiAl7O2N7的过程中,蒸发-凝聚的同时伴随着SiO气体的挥发,因此很难得到致密的AlON-SiAl7O2N7复相材料.研究了AlON-SiAl7O2N7复相材料在1300℃、空气中的抗氧化性能,同时作为比较,研究了相同条件下单相的AlON材料的抗氧化性能.结果表明,AlON-SiAl7O2N7复相材料显示了较之单相的AlON陶瓷材料更好的抗氧化性能,这是因为氧化过程中所形成的含玻璃相的表面氧化层抑制了氧的向内扩散所致.

  1. Betaalde arbeid als verdringer van vrijwilligerswerk? Overbelasting als mogelijke verklaring

    Directory of Open Access Journals (Sweden)

    Angela Kok-Van Meer

    2014-06-01

    Full Text Available Do paid work activities displace volunteering? A potential explanation from role overload theoryRecent changes in Dutch society might lead to a shortage of volunteers. On the one hand, the demand for volunteers is increasing: in the social welfare domain because of governmental austerity policies and in other domains such as sports because of the higher supervision intensity of activities. On the other hand, the supply of volunteers is likely to decrease as more and more women and older workers are active in the labor market, which reduces the time that is available for volunteering. Role overload theory would suggest that the increasing labor participation rate of certain categories of workers goes along with a decline of participation in voluntary work. The secondary data analysis shows that various role loads (work, care for children living at home are associated with differences in participation in voluntary work. However, while a higher number of contractual work hours and hours spent on work-related training are negatively associated with volunteer work, care for children living at home is positively associated with volunteering. These results provide only limited support for role overload theory.Betaalde arbeid als verdringer van vrijwilligerswerk? Overbelasting als mogelijke verklaringDe afgelopen jaren hebben zich enkele maatschappelijke veranderingen voorgedaan, die wellicht tot schaarste op de Nederlandse vrijwilligersmarkt zouden kunnen leiden. Enerzijds neemt de vraag naar vrijwilligers toe doordat subsidieregelingen versoberen (bijvoorbeeld in zorg en welzijn en de begeleidingsintensiteit in bepaalde organisaties stijgt (bijvoorbeeld in sport. Anderzijds neemt het aanbod van vrijwilligers af doordat vrouwen en ouderen meer en langer op de arbeidsmarkt actief zijn, waardoor minder tijd beschikbaar is voor vrijwilligerswerk. In dit artikel wordt aan de hand van de role overload theorie nagegaan of het al dan niet deelnemen aan

  2. Thermoluminescence properties of AlN ceramics

    DEFF Research Database (Denmark)

    Trinkler, L.; Christensen, P.; Agersnap Larsen, N.; Berzina, B.

    The paper describes thermoluminescence (TL) properties of AlN:Y2O3 ceramics irradiated with ionising radiation. A high TL sensitivity of AlN:Y2O3 ceramics to radiation encouraged a study of the AlN ceramics for application as a dosimetric material. The paper presents experimental data on: glow...

  3. Electroplating Zn-Al Alloy Technology

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The method of controlling separating anode and separating power source was used to perform orthogonal optimization for the parameters in electroplating Zn-Al alloy.The electroplating Zn-Al alloy technology was decided, in which the content of Al is about 12%-15%.

  4. The fabrication of 26Al targets

    International Nuclear Information System (INIS)

    Targets with up to 1.4x101626Al atoms have been fabricated. The artificial production of the 26Al nuclei via the reaction 26Mg(p, n)26Al was carried out at the cyclotrons in Juelich and Muenchen. The experimental procedures in the fabrication of these targets as well as some test measurements are described. (orig.)

  5. Nonstoichiometry of Al-Zr intermetallic phases

    Energy Technology Data Exchange (ETDEWEB)

    Radmilovic, V.; Thomas, G.

    1994-06-01

    Nonstoichiometry of metastable cubic {beta}{prime} and equilibrium tetragonal {beta} Al-Zr intermetallic phases of the nominal composition Al{sub 3}Zr in Al-rich alloys has been extensively studied. It is proposed that the ``dark contrast`` of {beta}{prime} core in {beta}{prime}/{sigma}{prime} complex precipitates, in Al-Li-Zr based alloys, is caused by incorporation of Al and Li atoms into the {beta}{prime} phase on Zr sublattice sites, forming nonstoichiometric Al-Zr intermetallic phases, rather than by Li partitioning only. {beta}{prime} particles contain very small amounts of Zr, approximately 5 at.%, much less than the stoichiometric 25 at.% in the Al{sub 3}Zr metastable phase. These particles are, according to simulation of high resolution images, of the Al{sub 3}(Al{sub 0.4}Li{sub 0.4}Zr{sub 0.2}) type. Nonstoichiometric particles of average composition Al{sub 4}Zr and Al{sub 6}Zr are observed also in the binary Al-Zr alloy, even after annealing for several hours at 600{degree}C.

  6. Topiramat als Phasenprophylaktikum - ein Fallbericht

    Directory of Open Access Journals (Sweden)

    Letmaier M

    2001-01-01

    Full Text Available Topiramat ist ein neues Antiepileptikum mit einem breiten Wirkspektrum. Aktuelle klinische Studien geben Hinweise darauf, daß Topiramat stimmungsstabilisierende Eigenschaften besitzt und somit effizient in der Behandlung der bipolaren affektiven Störung sein könnte. Vor dem Hintergrund dieser Studienberichte, behandelten wir eine 41jährige, erstmals vor 10 Jahren erkrankte Patientin mit der Diagnose einer therapierefraktären, bipolaren affektiven Störung (Rapid-Cycling mit Topiramat. Im Rahmen ihrer Erkrankung wurde die Patientin insgesamt 12mal stationär aufgenommen und meist aufgrund von akuten manischen Episoden behandelt. Dabei kamen seit 1991 folgende Phasenprophylaktika zur Anwendung: Carbamazepin, Valproat und Lamotrigin ? zuletzt nur mit mäßigem Erfolg. Daraufhin wurde zu Beginn einer neuerlichen manischen Episode ambulant eine Therapie mit Topiramat begonnen. Acht Wochen nach Therapiestart kam die Patientin in stationäre Behandlung. Der Aufenthalt dauerte weniger als drei Wochen; Topiramat wurde von der Patientin gut vertragen. Infolge eines belastenden Lebensereignisses kam es unter kontinuierlicher Therapie mit Topiramat zu einer Destabilisierung des psychischen Zustandsbildes (manische Symptome. Durch eine ambulante Erhöhung der Topiramatdosis bei gleichzeitiger Gabe von Risperidon und Clonazepam konnte jedoch eine neuerliche manische Episode erstmals ambulant behandelt werden. Die Patientin erhält derzeit 200 mg Topiramat pro Tag und ist seit mehr als 20 Monaten nahezu beschwerdefrei.

  7. Estimação da evapotranspiração de referência no estado do Rio de Janeiro usando redes neurais artificiais Reference evapotranspiration estimate in Rio de Janeiro state using artificial neural networks

    Directory of Open Access Journals (Sweden)

    Sidney S. Zanetti

    2008-04-01

    Full Text Available Propor uma rede neural artificial (RNA para estimar a evapotranspiração de referência (ETo em função das coordenadas de posição geográfica e da temperatura do ar no Estado do Rio de Janeiro, motivou a realização do presente estudo. Os dados utilizados no treinamento da rede foram obtidos de 17 séries históricas de elementos climáticos localizadas nesse Estado. A ETo diária calculada pelo método de Penman-Monteith (FAO-56 foi utilizada como referência para treinar as redes. As RNAs, do tipo perceptron de múltiplas camadas, foram treinadas para estimar a ETo em função da latitude, longitude, altitude, temperatura média do ar, amplitude térmica diária e dia do ano. Após o treinamento com várias configurações de rede, selecionou-se a que apresentou o melhor desempenho, a qual é composta de apenas uma camada intermediária (com vinte neurônios e função de ativação do tipo sigmóide logística e uma camada de saída (com um neurônio e função de ativação linear. Pelos resultados obtidos conclui-se que, levando-se em consideração apenas as coordenadas de posição geográfica e a temperatura do ar, pode-se estimar a ETo (valores diários em 17 localidades do Estado do Rio de Janeiro usando uma RNA.This work was performed with the aim of proposing an artificial neural network (ANN to estimate the reference evapotranspiration (ETo as a function of geographic position coordinates and air temperature in the State of Rio de Janeiro. Data used for the network training were collected from 17 historical time series of climatic elements located in the State of Rio de Janeiro. The daily ETo calculated by Penman-Monteith (FAO-56 method was used as a reference for network training. ANNs of multilayer perceptron type were trained to estimate ETo as a function of latitude, longitude, altitude, mean air temperature, thermal daily amplitude and day of the year. After training with different network configurations, the one showing

  8. Controle dos vasos renais usando clips vasculares e fio cirúrgico em nefrectomias vídeo-assistidas de doadores vivos Control of renal vessels using titanium clips and cotton suture in hand-assisted laparoscopic live donor nephrectomy

    Directory of Open Access Journals (Sweden)

    Alcides José Branco Filho

    2005-02-01

    Full Text Available OBJETIVO: A nefrectomia laparoscópica em doadores vivos para transplante renal vem assumindo um papel importante na era das cirurgias minimamente invasivas, acarretando menor morbidade aos doadores, e resultados semelhantes à técnica aberta no que se refere ao enxerto renal. O objetivo do presente artigo é relatar a experiência do nosso serviço utilizando a técnica de controle dos vasos renais usando fio cirúrgico e clips vasculares. MÉTODO: Foram realizadas 45 nefrectomias utilizando a técnica vídeo-assistida, com ligadura dos vasos renais com clips de titânio (LT-300 e fio cirúrgico. As variáveis analisadas foram tempo cirúrgico, perda sangüínea, tempo de isquemia quente, permanência hospitalar, necessidade de conversão e complicações. RESULTADOS: O procedimento foi realizado com sucesso em todos os casos. O tempo cirúrgico médio foi de 118 minutos, com perda sangüínea estimada em 84ml e tempo de isquemia quente de 4,3 minutos. Dois casos de íleo prolongado, uma lesão de veia gonadal, um escape de artéria renal e uma necrose de ureter foram observados. A permanência hospitalar média foi de 3,7 dias. O uso de clips vasculares e fio cirúrgico reduziu a perda de tecido venoso comparado à técnica com staplers e gerou redução de custos. CONCLUSÕES: A nefrectomia vídeo-assistida com a técnica descrita é factível e mostrou ser efetiva na contenção de gastos e na redução de tecido venoso perdido.BACKGROUND: Laparoscopic live donor nephrectomy has acquired an important role in the minimally invasive surgery era, decreasing morbidity to kidney donors, with an equivalent renal graft outcome compared with open surgery. The aim of this article is report our experience using the technique of renal vessels control with metallic clips and cotton suture. METHODS: Fourty-five nephrectomies were performed following the hand-assisted technique and using titanium clips (LT-300 and cotton suture for renal vessels

  9. Avaliação do custo do tratamento de úlceras por pressão em pacientes hospitalizados usando curativos industrializados Evaluation of the cost of treating pressure ulcers in hospitalized patients using industrialized dressings

    Directory of Open Access Journals (Sweden)

    Angela Cristina Beck Lima

    2011-01-01

    Full Text Available Este trabalho avaliou o uso de curativos industrializados: poliuretano, hidrogel, carvão ativo e também hidrogel com alginato, no tratamento de úlcera por pressão na Clínica Neurocirúrgica do Hospital da Restauração. O objetivo foi identificar o fator crítico que aumenta a demanda e custos com curativos industrializados. A avaliação, realizada na Clínica Neurocirúrgica, identificou os indivíduos que apresentaram risco de desenvolver úlcera por pressão. 62 pacientes foram avaliados e a prevalência foi de 22,6%, segundo escore obtido na escala de Braden. A avaliação comparativa entre indivíduos que receberam medidas preventivas e entre os que não receberam mostrou que o custo médio diário de hospitalização para o primeiro grupo foi 45% maior que para o segundo grupo. O teste de Wilcoxon-Mann-Withiney comparou a população de risco com a população de baixo risco, mostrando que a análise dos escores da Escala de Braden entre os grupos apresenta diferenças estatisticamente significativas quando estas duas populações são comparadas, intervalo de confiança de 95%. Úlcera por pressão é um indicador de qualidade dos serviços de saúde. Pode-se reduzir custo e oferecer serviços públicos de maior qualidade se forem implantados treinamentos com a equipe de enfermagem, usando um protocolo de medidas preventivas baseado em um teste de avaliação de risco como a escala de Braden.This work evaluated wound dresses used in the Neurosurgery Department of Restauração Hospital: polyurethane, hydrogel and activated carbon wound dresses and hydrogel with alginate used for pressure ulcer care. This work aimed to identify a critical factor that increases demand and cost of wound dresses. The evaluation conducted at the Neurosurgery Department identified individuals at risk of pressure ulcer development. Sixty-two patients were evaluated and the prevalence of pressure ulcer was 22.6% according to the Braden scale. Comparative

  10. Comparação entre as medidas da espessura central corneana usando a paquimetria óptica e a ultra-sônica Comparison between the measurements of central corneal thickness using optic and ultrasonic pachymeters

    Directory of Open Access Journals (Sweden)

    Aline Leonel Maimone

    2007-10-01

    Full Text Available OBJETIVOS: Comparar a medida da espessura corneana central (ECC obtida pelo paquímetro óptico Haag-Streit e a paquimetria ultrassônica DGH 500 (PachetteTM. MÉTODOS: Foram avaliados, 200 olhos de 100 pacientes utilizando-se o paquímetro óptico (PO e o ultrassônico (PU. As medidas foram realizadas na área central da córnea, respeitando a área dos 3 mm, em pacientes com córneas normais, em olhos hipermétropes, emétropes e míopes, excluindo doenças oculares, usuários de lentes de contato ou submetidos às cirurgias. RESULTADOS: A média geral da ECC medida pelo PO foi 603,8± 32,6µm, e 568,2±40,5 µm pelo PU. As comparações entre as medidas dos dois aparelhos foram realizadas ao nível de 5% de significância e a diferença entre os dois aparelhos foi 35,7±26,4 µm (p=0,0000, indicando diferença significativa entre os métodos utilizados. Não houve diferença estatística entre olhos hipermétropes, emétropes e míopes usando o PU. CONCLUSÃO: A medida da ECC é superestimada pelo PO quando comparada com o PU.PURPOSE: To compare measurements of central corneal thickness obtained using a Haag-Streit optic pachymeter and a DGH 500 (Pachette Ttm ultrasonic pachymeter in normal patients. METHODS: An evaluation was made of 200 eyes of 100 patients using Optic (PO and Ultrasonic (PU pachymeters. Measurements were made in the area of the central cornea (ECC respecting the 3.0 mm territory, in patients with normal corneas of hypermetropic, emetropic and myopic eyes. Patients with ocular diseases, ocular surgeries, and contact lens wearers, were excluded. A statistical analysis was performed using a Paired Student's t test to compare measurements between instruments at the 5% level of significance. RESULTS: The mean thickness of the ECC measured by the PO was 603.8±32.6µm and by the PU, 568.2±40.5µm. The difference between the two instruments was 35.7±26.4µm. Applying the t test with p = <5%, the difference was significant. We

  11. Produção de amilase por rizóbios, usando farinha de pupunha como substrato Production of amylase by rhizobia using peach palm flour as substrate

    Directory of Open Access Journals (Sweden)

    Arlem Nascimento de Oliveira

    2007-03-01

    Full Text Available As amilases estão entre as mais importantes enzimas industriais e são de grande interesse na biotecnologia atual. Embora elas possam ser derivadas de diversas fontes, as de origem microbiana são geralmente as mais procuradas pelas indústrias. As espécies do gênero Bacillus são consideradas as principais fontes de amilases. Apesar disso, a busca por novas fontes microbianas vem crescendo em todo o mundo. O presente estudo objetivou avaliar a produção de amilase por rizóbios nativos, usando farinha de pupunha como substrato. Neste estudo, foi adotado o delineamento experimental inteiramente casualizado, com três repetições. Foram determinados ainda os coeficientes de correlação de Pearson entre as variáveis pH do meio, proteína extracelular, biomassa celular, diâmetro médio da colônia (DMC, diâmetro médio do halo (DMH, índice enzimático (IE e atividade amilolítica das bactérias selecionadas. Dos 19 isolados com atividade amilolítica em meio YMA modificado, sete (36,8% exibiram "IE" > 2,1, o que permite considerá-los bons produtores de amilase. Os "IE" apresentados pelos isolados INPA R-987, 950 e 915B foram significativamente inferiores (p Amylases are among the most important industrial enzymes and are of great significance in present-day biotechnology. Although they can be derived from various sources, enzymes from microbial sources are generally the most required by industry. Species of the genus Bacillus are considered to be the main sources of amylases, although screening for new microbial sources is increasing all over the world. The objective of the present study was to evaluate the production of amylase by indigenous rhizobia, using peach palm flour as substrate. In this study, a completely randomized experimental design was adopted with three replicates. Pearson's correlation coefficients were calculated for medium pH, extracellular protein, cellular biomass, mean colony diameter (MCD, mean halo diameter (MHD

  12. Rhizobia amylase production using various starchy substances as carbon substrates Produção de amilase por rizóbios, usando várias substâncias amiláceas como substratos de carbono

    Directory of Open Access Journals (Sweden)

    Arlem Nascimento de Oliveira

    2007-06-01

    Full Text Available Six isolates of indigenous rhizobia of Central Amazonia were screened for the production of amylases in liquid media using various starchy substances as carbon sources. All rhizobia strains could produce more extracellular protein, biomass and amylases with the different kinds of carbon substrates. Among the carbon sources tested maltose was the best substrate for protein and amylase production. In general, peach palm flour and corn starch (maizena® were also considered to be good carbon sources for rhizobia amylases. On the other hand, the biomass production by the rhizobia isolates was higher in the presence of oat flour. INPA strain R-926 was a good amylase producer in maltose (1.94 U and corn starch (0.53 U media. INPA strain R-991 was also a good amylase producer in maltose (1.66 U and corn starch (1.59 U yielding significant extracellular amylase. Correlation analysis showed significant and positive relationships between rhizobia amylases and final pH (r = 0.49, P Seis isolados de rizobia nativos da Amazonia Central foram selecionados para a produção de amilases em meio de cultura líquido, usando várias substâncias amiláceas como fontes de carbono. Os resultados mostraram que todos os isolados de rizobia podem produzir quantidades diferenciadas de proteína extracelular, biomassa e amilases com diferentes tipos de fontes de carbono. Entre as fontes testadas, maltose foi a melhor para as produções de proteína e amilase. Por outro lado, a produção de biomassa pelos isolados de rizobia foi maior na presença de farinha de aveia. O isolado INPA R-926 mostrou-se um bom produtor de amilase nos meios com maltose (1,94 U e amido de milho (0,53 U. O isolado INPA R-991 também foi um bom produtor de amilase com rendimentos significativos na presença de maltose (1,66 U e amido de milho (1,59 U. As análises de correlação revelaram relações positivas e significativas entre as atividades de amilase e pH final (r = 0,49, P < 0,05, prote

  13. Calculation of attenuation by rain using the DAH model and diameter of antennas for the Ka Band in Mexico; Calculo de atenuacion por lluvia usando el modelo DAH y diametro de antena para Banda Ka en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Landeros-Ayala, S.; Neri-Vela, R; Cruz-Sanchez, H.; Hernandez-Bautista, H. [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)

    2002-03-01

    Fatim Haidara), combinado con los mapas globales de distribucion de lluvia de Crane, para el calculo de la atencion por lluvia en sistema de comunicacion por satelite que operen en la Banda Ka. Ademas, se proponen diametros de antena para los sistemas de comunicaciones en Banda Ka en diferentes localidades de la Republica Mexicana, empleando para ello, los margenes de atencion por lluvia obtenidos a trav del Modelo DAH, y usando como referencia las caracteristicas del satelite de comunicaciones ANIK F2 y de una estacion terrena VSAT.Se muestra una fig. de la atenuacion por lluvia a 27.5 gHz y de los diametros de antena para banda Ka en Mexico. Se da una tabla de la atenuacion por lluvia a 29.5 GHz y a 20.2 GHz.

  14. Systems Engineering Techniques for ALS Decision Making

    Science.gov (United States)

    Rodriquez, Luis F.; Drysdale, Alan E.; Jones, Harry; Levri, Julie A.

    2004-01-01

    The Advanced Life Support (ALS) Metric is the predominant tool for predicting the cost of ALS systems. Metric goals for the ALS Program are daunting, requiring a threefold increase in the ALS Metric by 2010. Confounding the problem, the rate new ALS technologies reach the maturity required for consideration in the ALS Metric and the rate at which new configurations are developed is slow, limiting the search space and potentially giving the perspective of a ALS technology, the ALS Metric may remain elusive. This paper is a sequel to a paper published in the proceedings of the 2003 ICES conference entitled, "Managing to the metric: an approach to optimizing life support costs." The conclusions of that paper state that the largest contributors to the ALS Metric should be targeted by ALS researchers and management for maximum metric reductions. Certainly, these areas potentially offer large potential benefits to future ALS missions; however, the ALS Metric is not the only decision-making tool available to the community. To facilitate decision-making within the ALS community a combination of metrics should be utilized, such as the Equivalent System Mass (ESM)-based ALS metric, but also those available through techniques such as life cycle costing and faithful consideration of the sensitivity of the assumed models and data. Often a lack of data is cited as the reason why these techniques are not considered for utilization. An existing database development effort within the ALS community, known as OPIS, may provide the opportunity to collect the necessary information to enable the proposed systems analyses. A review of these additional analysis techniques is provided, focusing on the data necessary to enable these. The discussion is concluded by proposing how the data may be utilized by analysts in the future.

  15. El efecto de la distancia al mercado sobre la pobreza rural en la Región Metropolitana de Santiago

    Directory of Open Access Journals (Sweden)

    Rodrigo Pérez

    2013-01-01

    Full Text Available La pobreza en Chile ha disminuido notablemente desde 1990. En el año 2006, la incidencia de la pobreza rural cayó bajo la de áreas urbanas, debido en parte a la movilidad poblacional. No obstante, los pobres rurales mantienen niveles educacionales y de ingresos bajos, lo que se explica, en parte, por el mayor aislamiento y el menor acceso que tienen a los mercados. Teniendo eso en consideración, este estudio sostiene que la distancia a áreas urbanas (en tiempo de viaje se encuentra correlacionada con la pobreza, una vez que se controla por otros factores. Usando un modelo econométrico que relaciona información geográfica y socioeconómica de la Región Metropolitana, se concluye que el nivel de pobreza en un sector censal aumenta con la distancia, y que para una determinada distancia, la tasa de pobreza es menor si aumenta el acceso a medios de movilización, al mitigar el efecto de distancia.The national poverty headcount in Chile has declined considerably since 1990. In 2006, rural poverty ratefell below that of urban areas, due in part to population mobility. Rural areas, however, are still characterized by low educational levels and incomes, explained, in part, by low population density, remoteness to services, and limited access to markets for rural-produced products. This study finds that distance (measured as travel time of rural populations to urban areas is associated with the incidence of poverty in rural communities after controlling for other factors. Using an econometric model based on geographical and socioeconomic information of the Metropolitan Region of Santiago, the studyfinds that poverty levels in census tracts increase with distance to Santiago, and, for a given distance, access to transportation reduces poverty, through a mitigation of the distance effect.

  16. Child malnutrition in Mexico in the last two decades: prevalence using the new WHO 2006 growth standards Malnutrición preescolar en México en las últimas dos décadas: prevalencias usando los estándares de la OMS-2006

    Directory of Open Access Journals (Sweden)

    Teresa González-de Cossío

    2009-01-01

    Full Text Available OBJECTIVE: To describe preschool malnutrition prevalence and trends in Mexican children for the 1988, 1999 and 2006 Mexican National Nutrition Surveys using WHO-2006 standards and National Center for Health Statistics/WHO (NCHS/WHO references. MATERIAL AND METHODS: Prevalence of undernutrition ( plus 2 z-score for weight/height were calculated. RESULTS: Height/age and weight/height have increased over time (pOBJETIVO: Describir las prevalencias y tendencias de malnutrición en preescolares mexicanos, según resultados de las Encuestas Nacionales de Nutrición 1988, 1999 y 2006, usando estándares de la Organización Mundial de la Salud de 2006 y referencias del National Center for Health Statistics/ World Health Organization (NCHS/WHO. MATERIAL Y MÉTODOS: Se calcularon prevalencias de desnutrición (puntaje z +2z peso/talla. RESULTADOS: La talla/edad y el peso/talla han aumentado con el tiempo (p< 0.05. Usando los estándares de la OMS de 2006, el desmedro en menores de cinco años de edad era de 26.9, 21.5 y 15.5% en 1988, 1999 y 2006, respectivamente. Los valores de emaciación fueron 6.2, 2.1 y 2.0%. La emaciación en 2006 en los menores de seis meses de edad fue de 4.9%. El sobrepeso aumentó de 1988 a 1999 (6.1 a 7.5% y se estabilizó en 2006 (7.6%. Las diferencias entre grupos étnicos y socioeconómicos disminuyeron con el tiempo. CONCLUSIONES: El desmedro disminuyó marcadamente, pero continúa siendo el principal problema de malnutrición. El sobrepeso emergió como problema de salud pública en niños. Las estimaciones de desnutrición en preescolares previamente publicadas usando las referencias del NCHS/WHO subestimaban las verdaderas cifras. Las desviaciones en la talla alcanzada a partir de los 12 meses de edad revelan prácticas de lactancia y alimentación infantil pobres, probablemente aunadas a infecciones tempranas. Estos resultados refuerzan la necesidad de mejorar la calidad de los programas de nutrición y de promover pr

  17. Polythermal cutting of Al-Si-YAl2 system

    International Nuclear Information System (INIS)

    Given the out come of the research of the Al-Si-YAl2 system with studies of polythermal cutting. It was found out that the most cutting of Al-YSi2Al2, Al-YSiAl2, Al-Y5SiAl14, YSiAl2-YSi2Al2, Y5SiAl14-YSiAl2 and Y5SiAl14-YAl2, Si-YSiAl2 has the nature of quasibinary eutectics

  18. Progresses in analyzing 26Al with SMCAMS

    International Nuclear Information System (INIS)

    Shanghai Mini-Cyclotron based Accelerator Mass Spectrometer (SMCAMS) was especially designed for analyzing 14C. In order to accelerate and analyze 26Al the accelerated orbit and beam optics in injection system were calculated and harmonic number and acceleration turns was optimized. Preliminary experiment was carried out. In which a beam current of 1.15 x 10-9A for 27Al- and 0.038 CPS background for 26Al were measured. The limited sensitivity of 26Al/27Al is 5.25 x 10-12. (authors)

  19. AlON粉体的合成

    Institute of Scientific and Technical Information of China (English)

    赵小军; 茹红强; 张宁; 孙有政

    2009-01-01

    以α-Al2O3和AlN为原料,利用高温固相反应在氮气气氛下常压合成了AlON粉体。研究了成分配比、合成温度、保温时间对合成AlON粉体含量的影响,并通过热分析测试了合成过程热流和质量的变化。结果表明,当原料Al2O3和AlN的质量比为81:18、合成工艺为1750℃,2h时,得到AlON相的含量达到95%以上。

  20. Trato verbal paterno al adolescente

    Directory of Open Access Journals (Sweden)

    Rodríguez Juan Carlos

    1995-06-01

    Full Text Available

    En alguna ocasión se ha escuchado una palabra, que causa un sentimiento y a la vez un recuerdo, que lleva a evocar la adolescencia o la infancia, se recuerda quien la pronunciaba y en que ocasión la decía. Este es el poder que tiene una palabra y más aún si es dicha por el padre, puesto que este es la figura significativa que se lleva en la memoria. De aquí nace el interés de realizar un estudio, en donde se describe y analice la percepción y el sentimiento del adolescente, quien en esta etapa es vulnerable al cambio, ya que está buscando su propia identidad; que con el trato verbal paterno la encontrara sin ninguna dificultad o por el contrario nunca la encontrará.

     

  1. Orientation of Al3Ti platelets in Al-Al3Ti functionally graded material manufactured by centrifugal method

    International Nuclear Information System (INIS)

    Al-Al3Ti functionally graded materials (FGMs) were manufactured by the centrifugal method with a commercial ingot of Al-5 mass% Ti master alloy. The alloy was melted at a liquid/solid coexisting temperature, at which Al3Ti remains as a solid, and then it was cast into a thick-walled ring. It was found that the Al-Al3Ti functionally graded material can be successfully fabricated by the centrifugal method. It was also found that the volume fraction of the Al3Ti can be increased by repetition of the centrifugal method. Since the shape of Al3Ti particles in a commercial alloy ingot is that of a platelet, the Al3Ti particles are arranged with their platelet planes nearly perpendicular to the radial direction. The orientation effects become stronger when the G number becomes larger. Although the final centrifugal casting was conducted under a very large centrifugal force for the specimen cast three times, the orientation effects were weaker than those in the specimen cast one time. From these observations, it is concluded that the origin of orientation of Al3Ti platelets can be attributed to the angular velocity gradient of the melt along the radial direction produced by the difference in the viscosity. (orig.)

  2. TEM characterization of Al-C-Cu-Al2O3 composites produced by mechanical milling

    International Nuclear Information System (INIS)

    Novel Al-based composites (Al-C-Cu-Al2O3) obtained by mechanical milling (MM), were characterized by transmission electron microscopy (TEM) and electron energy loss spectroscopy (EELS). Analyses of composites were carried out in both, the as-milled and the as-sintered conditions. C nanoparticles were found in the as-milled condition and Al2O3 nanofibers were found in as-sintered products, as determined by EELS. C and Cu react with Al to crystallize in Al3C4 and Al2Cu structures, respectively

  3. MARTENSITIC TRANSFORMATION AND THERMAL STABILITY IN Cu-Al-Co AND Cu-Al-Zr ALLOYS

    Institute of Scientific and Technical Information of China (English)

    Y. Q. Ma; C.B. Jiang; H.B. Xu

    2003-01-01

    Cu-Al-Co and Cu-Al-Zr alloys were explored with Co or Zr additions in Cu-Al alloys for high temperature shape memory alloys. Samples were quenched after homogenized at 850℃ for 48h. It was found that both Cu-Al-Co and Cu-Al-Zr show AlCu3 martensitic phase at room temperature and exhibit martensitic transformation temperatures higher than 200℃, showing the potentials for developing as high temperature shape memory alloys. Thermal cycles were performed by DSC instrument on both Cu-Al-Co and Cu-Al-Zr alloys. The results show that Cu-Al-Co loses its martensitic transformation after five thermal cycles, and Cu-Al-Zr exhibits no martensitic transformation in the second thermal cycle.

  4. INDICADORES FECALES Y PATÓGENOS EN AGUA DESCARGADA AL RÍO BRAVO

    Directory of Open Access Journals (Sweden)

    Evangelina Olivas-Enriquez

    2011-01-01

    Full Text Available Existen pocos estudios disponibles con base en microorganismos enteropatógenos que confirmen el impacto del Río Bravo en la frontera norte sobre la salud pública, aunque algunos datos revelan descargas diarias de millones de litros de aguas residuales, la mayoría sin el más mínimo tratamiento. Las partes bajas del río reciben las aguas negras de áreas urbanas, drenaje agrícola y descargas de la industria, lo que sugiere su alta y peligrosa contaminación con patógenos intestinales. El objetivo fue determinar la calidad microbiológica del agua del Río Bravo, proveniente de drenes y canales que desembocan en ambos lados de la frontera Juárez- El Paso (región denominada Paso del Norte mediante la detección de organismos indicadores de contaminación fecal, los que permiten inferir la presencia de patógenos intestinales. Se identificaron y cuantificaron los indicadores fecales Cryptosporidium y Giardia por técnicas de separación inmunomagnética e inmunofluorescencia; otros indicadores fueron las bacterias coliformes totales y Escherichia coli, usando la técnica de filtración por membrana. Los resultados mostraron que el 100% de las muestras presentaron los dos parásitos y por lo menos alguno de los indicadores bacterianos, aunque en números fluctuantes, atribuido al tipo de descargas. Con base en que estos indicadores deben ser cero en el agua para beber y utilizando referencias para cuerpos de agua, se pudo deducir la calidad microbiológica, no siendo segura en el 100% de las muestras ni para actividades recreativas ni aptas para riego agrícola. Se observó un número mayor de parásitos y bacterias en las muestras del lado mexicano; asimismo, en ambas fronteras se encontró un número mayor del parásito Giardia que de Cryptosporidium. Actualmente la presencia indiscutible de enteropatógenos en el agua del Río Bravo constituye un riesgo para la salud pública, principalmente para los agricultores que la manejan y en el

  5. Concentração espermática e tempo de incubação na fecundação in vitro usando-se sêmen de touros da raça Guzerá Sperm concentration and incubation period on in vitro fecundation using sperm of Guzera bulls

    OpenAIRE

    L.P.B. Dias; W.F. Sá; L.S.A. Camargo; A.A. Ramos; A.M. Ferreira; J.H.M. Viana; L.A.G. Nogueira

    2006-01-01

    Estudou-se o efeito da concentração espermática e período de incubação e da interação dessas características sobre a fecundação in vitro (FIV) usando-se sêmen de touros Guzerá. Oócitos (n=1146) maturados in vitro foram divididos em tratamentos objetivando a FIV, em esquema fatorial 3×2×2 (três touros - A, B e C, duas concentrações espermáticas - 2 e 4×10(6) espermatozóides/ml e dois tempos de incubação 12 e 18 horas). Utilizaram-se espermatozóides viáveis obtidos por swin-up...

  6. Rastreamento da fibrose cística usando-se a análise combinada do teste de IRT neonatal e o estudo molecular da mutação deltaF508 Cystic fibrosis screening by two-tiered newborn IRT assay and deltaF508 mutation molecular analysis

    OpenAIRE

    Giselda M.K. Cabello; Cabello, Pedro H.; Silvia R.S. Roig; Armando Fonseca; Eulália C.D. Carvalho; Octavio Fernandes

    2003-01-01

    Um total de 117 cartões de rastreamento neonatal foi selecionado anonimamente para a avaliação de fibrose cística (FC) pela análise da mutação deltaF508 usando-se a técnica da reação em cadeia da polimerase (PCR), seguida de eletroforese em gel de poliacrilamida (Page) e pela quantificação da imunotripsina reativa (IRT, Delfia). Uma concentração de IRT menor que 140ng/ml foi encontrada em 116 recém-nascidos. Entre estes foi detectado um heterozigoto deltaF508 com uma concentração de IRT de 4,...

  7. Determinação espectrofotométrica do arsênio em solo da cidade de Santana-AP usando o método do dietilditiocarbamato de prata (SDDC) modificado Arsenic spectrophotometric determination in soil of the Santana-AP city using the silver diethyldithiocarbamate (SDDC) modified method

    OpenAIRE

    Simone de Fátima Pinheiro Pereira; Geiso Rafael Fonseca Oliveira; Johny da Silva Oliveira; Juliane da Silva e Silva; Pedro Moreira de Sousa Junior

    2009-01-01

    Várias toneladas de rejeito de manganês contendo arsênio, gerado por uma empresa de mineração, foram utilizadas como aterro de ruas da cidade de Santana-AP. A possibilidade de exposição das pessoas residentes nessas localidades levou ao estudo de quantificação de arsênio total nos solos. Após a digestão, os teores de arsênio foram quantificados por espectrofotometria de absorção molecular usando um sistema automático de geração de hidretos (HG-MAS), diciclohexilamina/CHCl3 como solvente do di...

  8. Influences of Al particles on the microstructure and property of electrodeposited Ni-Al composite coatings

    Science.gov (United States)

    Cai, Fei; Jiang, Chuanhai

    2014-02-01

    Ni-Al composite coatings with different contents of Al microparticles were prepared from a conventional Watt bath. The influences of Al particle loadings in the bath on the surface morphology, composition, texture, grain size, microstrain, residual stress and anti-corrosion of the Ni-Al composite coating were investigated. The friction coefficients of the coatings at 200 °C were also evaluated by a pin-on-disctribometer. The results showed that the surface morphology of the coatings changed from pyramid + colonied structure to colonied structure with increasing Al particle loadings. The (2 0 0) preferred orientation for pure Ni coating evolved to random orientation with increasing Al particle loadings. The grain size obtained the minimum value of 72.28 nm at Al particle loading of 100 g/L and the microstrain of the coating increased with increasing the Al particle loadings. The incorporation of Al particles decreased the residual stress of the electro-deposited coating and all the coatings deposited at different Al particle loadings possessed low residual stress. As the Al particle loading increased, the anti-corrosion of the Ni-Al coatings increased owing to the combined effect of increasing Al content in the coatings and the texture evolution from (2 0 0) plane to (1 1 1) plane. The wear result suggested that the increasing Al particle content did not improve the wear performance of the Ni-Al composite coatings.

  9. Efficiency droop in high-Al-content AlGaN/AlGaN quantum wells

    Energy Technology Data Exchange (ETDEWEB)

    Tamulaitis, G.; Mickevicius, J.; Kazlauskas, K.; Zukauskas, A. [Institute of Applied Research and Department of Semiconductor Physics, Vilnius University, Sauletekio 9-III, 10222 Vilnius (Lithuania); Shur, M.S. [Department of ECE and CIE, Rensselaer Polytechnic Institute, 110 Eighth Street, Troy, NY 12180 (United States); Yang, J.; Gaska, R. [Sensor Electronic Technology Inc., 1195 Atlas Road, Columbia, SC 29209 (United States)

    2011-07-15

    Excitation power density dependence of photoluminescence (PL) efficiency is studied in the temperature range from 8 to 300 K for AlGaN multiple quantum well structures containing quantum wells of different width. PL efficiency droop is observed and dependence of the droop effect on the well width and lattice temperature is discussed. Photoluminescence band shape reveals strong carrier heating. It is shown that the heating effect has a substantial influence on the photoluminescence efficiency droop, especially at low lattice temperatures. Fitting of the temperature dependence of the PL band width with that obtained by the Monte Carlo simulation of carrier (exciton) hopping via localized states shows that (i) the potential fluctuations can be fairly accurately described using a double-scaled potential profile model, (ii) the localization becomes stronger in narrower quantum wells. (copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  10. Al-Si/Al2O3 in situ composite prepared by displacement reaction of CuO/Al system

    Directory of Open Access Journals (Sweden)

    Zhang Jing

    2010-02-01

    Full Text Available Al2O3 particle-reinforced ZL109 composite was prepared by in situ reaction between CuO and Al. The microstructure was observed by means of OM, SEM and TEM. The Al2O3 particles in sub-micron sizes distribute uniformly in the matrix, and the Cu displaced from the in situ reaction forms net-like alloy phases with other alloy elements. The hardness and the tensile strength of the composites at room temperature have a slight increase as compared to that of the matrix. However, the tensile strength at 350 ℃ has reached 90.23 MPa, or 16.92 MPa higher than that of the matrix. The mechanism of the reaction in the CuO/Al system was studied by using of differential scanning calorimetry(DSC and thermodynamic calculation. The reaction between CuO and Al involves two steps. First, CuO reacts with Al to form Cu2O and Al2O3 at the melting temperature of the matrix alloy, and second, Cu2O reacts with Al to form Cu and Al2O3 at a higher temperature. At ZL109 casting temperature of 750–780 ℃, the second step can also take place because of the effect of exothermic reaction of the first step.

  11. Fabrication of TiAl3 coating on TiAl-based alloy by Al electrodeposition from dimethylsulfone bath and subsequent annealing

    OpenAIRE

    Miyake, Masao; Tajikara, Seiya; Hirato, Tetsuji

    2011-01-01

    TiAl3 coating was formed on TiAl alloy by Al electrodeposition from a dimethylsulfone (DMSO2) bath and subsequent annealing. Before the Al electrodeposition, anodic dissolution of TiAl substrate in the DMSO2 bath was conducted to remove the surface oxide layer of the TiAl substrate. By performing the Al electrodeposition immediately after the anodic dissolution, uniform Al films adherent to the TiAl substrate could be obtained. Annealing at 650–1000 °C yielded a single TiAl3 layer or two laye...

  12. Orientation relationship of eutectoid FeAl and FeAl2

    Science.gov (United States)

    Scherf, A.; Kauffmann, A.; Kauffmann-Weiss, S.; Scherer, T.; Li, X.; Stein, F.; Heilmaier, M.

    2016-01-01

    Fe–Al alloys in the aluminium range of 55–65 at.% exhibit a lamellar microstructure of B2-ordered FeAl and triclinic FeAl2, which is caused by a eutectoid decomposition of the high-temperature Fe5Al8 phase, the so-called ∊ phase. The orientation relationship of FeAl and FeAl2 has previously been studied by Bastin et al. [J. Cryst. Growth (1978 ▸), 43, 745] and Hirata et al. [Philos. Mag. Lett. (2008 ▸), 88, 491]. Since both results are based on different crystallographic data regarding FeAl2, the data are re-evaluated with respect to a recent re-determination of the FeAl2 phase provided by Chumak et al. [Acta Cryst. (2010 ▸), C66, i87]. It is found that both orientation relationships match subsequent to a rotation operation of 180° about a 〈112〉 crystallographic axis of FeAl or by applying the inversion symmetry of the FeAl2 crystal structure as suggested by the Chumak data set. Experimental evidence for the validity of the previously determined orientation relationships was found in as-cast fully lamellar material (random texture) as well as directionally solidified material (∼〈110〉FeAl || solidification direction) by means of orientation imaging microscopy and global texture measurements. In addition, a preferential interface between FeAl and FeAl2 was identified by means of trace analyses using cross sectioning with a focused ion beam. On the basis of these habit planes the orientation relationship between the two phases can be described by (01)FeAl || (114) and [111]FeAl || [10]. There is no evidence for twinning within FeAl lamellae or alternating orientations of FeAl lamellae. Based on the determined orientation and interface data, an atomistic model of the structure relationship of Fe5Al8, FeAl and FeAl2 in the vicinity of the eutectoid decomposition is derived. This model is analysed with respect to the strain which has to be accommodated at the interface of FeAl and FeAl2. PMID:27047304

  13. Electron channelling enhanced microanalysis on Ni-Al-Mn and Al-Mn-Si

    International Nuclear Information System (INIS)

    Atom location by channelling enhanced microanalysis (ALCHEMI) was performed for Ni-Al-Mn compounds and Al-Mn-Si quasicrystals. For Ni75Al25-xMnx (x=5,9) with the L12-type structure, an occupation fraction of Mn atoms at the Ni site was quantitatively determined using planar channelling conditions. The occupation fraction increases with the Mn concentration or by quenching the compound from high temperature. In quasicrystals of Al74Mn20Si6 and Al68Mn20Ru8Si4, axial channelling conditions were used to locate Si and Ru, respectively. It was shown that Si atoms occupy the Al site in Al74Mn20Si6 whereas Ru atoms occupy the site different from that of Al in Al68Mn20Ru8Si4. (author)

  14. Microstructure and mechanical properties of Ti2AlC-reinforced TiAl composites

    International Nuclear Information System (INIS)

    Ti2AlC/TiAl composites were successfully in-situ synthesized by reaction hot pressing using Ti, Al, TiC and CNTs as starting materials. The results indicate that the as-sintered composites mainly consist of Ti2AlC and TiAl phases. The mechanical properties of the 23 wt.% Ti2AlC/TiAl composite exhibit the highest values, with a flexural strength and fracture toughness of 652.5 ± 76.8 MPa and 6.6 ± 0.5 MPa m1/2, respectively. The complex structure coupled with dispersed Ti2AlC micro-particulates is responsible for the enhancement in the strength. Toughening of the composite is mainly attributed to crack deflection, crack bridging, crack branching and pull-out of the Ti2AlC particles, as well as transgranular cracking.

  15. High pressure studies of UFe5Al7 and UFe7Al5 actinide compounds

    International Nuclear Information System (INIS)

    The ternary inter-metallic compounds, UFe5Al7 and UFe7Al5, crystallize in a tetragonal ThMn12 type structure. In the as-cast samples a residual phase of FeAl (∼2%wt) was identified in the grain boundaries. The amount of the residual cubic phase of FeAl was determined by Rietveld analysis and reduced by the annealing process. UFe5Al7 and UFe7Al5 maintain the tetragonal symmetry as a function of pressure, while FeAl keeps the cubic structure as was determined by the Rietveld analysis. The volume-pressure curve calculated from the X-ray analysis gives V/V0=0.87 for UFe5Al7 at 26.0 GPa and 0.89 at 24.6 GPa for UFe7Al5. (author)

  16. Chemical mixing at "Al on Fe" and "Fe on Al" interfaces

    Science.gov (United States)

    Süle, P.; Kaptás, D.; Bujdosó, L.; Horváth, Z. E.; Nakanishi, A.; Balogh, J.

    2015-10-01

    The chemical mixing at the "Al on Fe" and "Fe on Al" interfaces was studied by molecular dynamics simulations of the layer growth and by 57Fe Mössbauer spectroscopy. The concentration distribution along the layer growth direction was calculated for different crystallographic orientations, and atomically sharp "Al on Fe" interfaces were found when Al grows over (001) and (110) oriented Fe layers. The Al/Fe(111) interface is also narrow as compared to the intermixing found at the "Fe on Al" interfaces for any orientation. Conversion electron Mössbauer measurements of trilayers—Al/57Fe/Al and Al/57Fe/Ag grown simultaneously over Si(111) substrate by vacuum evaporation—support the results of the molecular dynamics calculations.

  17. Fabrication of /sup 26/Al targets

    Energy Technology Data Exchange (ETDEWEB)

    Buchmann, L.; Baumeister, H.; Rolfs, C.

    1984-06-01

    Targets with up to 1.4x10/sup 16/ /sup 26/Al atoms have been fabricated. The artificial production of the /sup 26/Al nuclei via the reaction /sup 26/Mg(p, n)/sup 26/Al was carried out at the cyclotrons in Juelich and Muenchen. The experimental procedures in the fabrication of these targets as well as some test measurements are described.

  18. The wobbler mouse, an ALS animal model

    OpenAIRE

    Moser, Jakob Maximilian; Bigini, Paolo; Schmitt-John, Thomas

    2013-01-01

    This review article is focused on the research progress made utilizing the wobbler mouse as animal model for human motor neuron diseases, especially the amyotrophic lateral sclerosis (ALS). The wobbler mouse develops progressive degeneration of upper and lower motor neurons and shows striking similarities to ALS. The cellular effects of the wobbler mutation, cellular transport defects, neurofilament aggregation, neuronal hyperexcitability and neuroinflammation closely resemble human ALS. Now,...

  19. A New Phase in ALS Research.

    Science.gov (United States)

    Chong, P Andrew; Forman-Kay, Julie D

    2016-09-01

    In this issue of Structure, Conicella et al. (2016) present evidence that the low complexity C-terminal region of TDP-43 undergoes liquid-liquid phase separation. ALS-associated mutations alter this phase separation process, providing a possible mechanism for the pathology caused by these TDP-43 mutations. The work is strongly supportive of toxic loss of RNA processing function in ALS. PMID:27602988

  20. Growth of CdTe: Al films

    International Nuclear Information System (INIS)

    CdTe: AI films were grown by the close space vapor transport technique combined with free evaporation (CSVT-FE). The Aluminum (Al) evaporation was made by two kinds of sources: one made of graphite and the other of tantalum. The films were deposited on glass substrates. The Al source temperature was varied maintaining the CdTe source temperature fixed as well as the substrate temperature. The films were characterized by x-ray energy dispersive analysis (EDAX), x-ray diffraction and optical transmission. The results showed for the films grown with the graphite source for Al evaporation, the Al did not incorporate in the CdTe matrix, at least to the level of EDAX sensitivity; they maintained the same crystal structure and band gap. For the samples grown with the tantalum source, we were able to incorporate the Al. The x-ray diffraction patterns show that the films have a crystal structure that depends on Al concentration. They were cubic up to 2.16 at. % Al concentration; for 19.65 at. % we found a mixed phase; for Al concentration higher than 21 at. % the films were amorphous. For samples with cubic structure it was found that the lattice parameter decreases and the band gap increases with Al concentration. (Author)

  1. Genetics of Familial and Sporadic ALS

    Science.gov (United States)

    2016-03-21

    Amyotrophic Lateral Sclerosis (ALS); Familial Amyotrophic Lateral Sclerosis; Amyotrophic Lateral Sclerosis With Frontotemporal Dementia; Lou Gehrig's Disease; Motor Neuron Disease; Primary Lateral Sclerosis

  2. 关于w-al-CL空间%On w-al-CL Spaces

    Institute of Scientific and Technical Information of China (English)

    林丽琼; 张云南

    2011-01-01

    给出w-al-CL空间的定义,比较几种CL性的关系,讨论w-al-CL空间的c0和与l1和的稳定性,并讨论C(K,X)空间的w-al-CL性.%Gives the definition of w-al-CL spaces, compare the relationship of some properties of CL, discusses the stability of c0 -sums and l1 -sums of w-al-CL spaces, and discusses the property of w-al-CL of C(K,X) spaces.

  3. Interfacial strength of Al/Al and Al/Zr/Du-10wt%Mo subject to different loading modes

    International Nuclear Information System (INIS)

    Compact tension (CT) experiments were conducted with fixtures that allowed mode-I (tensile opening mode), mode-Il (shearing mode), and mixed-mode loading to measure the interfacial strength between HIP-clad Al and Al, and Al and Zr/DU-10wt%Mo. Specimens were made with the same HIP process used for making thin composite foils, but instead used 25 mm thick Al-6061 cladding that allowed specimens to be gripped without adhesives. Three configurations of specimens were tested: (1) Al/Al specimens with a pre-crack along the seam; (2) specimens containing both a Zr/DU-10wt%Mo layer and an Al/Al seam along part of the interface; and (3) specimens containing only a Zr/DU-10wt%Mo layer at the interface, but with a pre notch along part of the interface. Digital image correlation (DIC) was used to measure full-field deformations during the test. The results show that mode-I loaded interfaces exhibit the weakest strength and the widest scatter. The strength increases when more shearing component is introduced

  4. Estudio de la fracción de materia orgánica de mayor remoción en el proceso de coagulación-floculación usando agua superficial

    Directory of Open Access Journals (Sweden)

    Indiana García

    2011-06-01

    óbica (MH y ligeramente hidrofóbica (LH; y el tipo hidrofílica formada por las fracciones cargada (CHA y neutral (NEU. Las aguas obtenidas de cada fracción fueron sometidas a un proceso de coagulación-floculación-sedimentación a escala de laboratorio usando sulfato de aluminio como coagulante; donde la fracción hidrofílica (CHA y NEU fue poco removida ( 65 %. Se utilizaron parámetros sustitutos para caracterizar dicha MON como carbono orgánico disuelto (COD, color, absorbancia ultravioleta (UV y absorbancia especifica ultravioleta (SUVA. Se determinó que estas aguas cruda presentan una mezcla de materia orgánica hidrofóbica e hidrofílica ya que los valores de SUVA estaban entre 2-4 L/mg-m, sin embargo la fracción hidrofóbica (MH+LH fue la predominante ya que representa 63.6 % y 65 % medidos como COD en época seca para Boaco y Juigalpa respectivamente, en época lluviosa los porcentajes fueron un poco más alto (71.2 % y 66.1 %. Finalmente se halló que el agua de río (Boaco contiene mayor concentración de trihalometanos (89-166 µg/L que el agua del lago (Juigalpa (28-80 µg/L después de ser clorada. Encontrándose que la fracción hidrofóbica fue la que más contribuyó a la formación de trihalometanos (THMs en 68.5 % (Boaco y 78.6 % (Juigalpa en la época seca en ambas aguas tratadas. Para la época lluviosa, la formación de THMs fue un poco mayor.Palabras claves: Materia orgánica; Trihalometanos; Fraccionamiento; Agua superficial

  5. Cognitive control associated with irritability induction: an autobiographical recall fMRI study Controle cognitivo associado à indução de irritabilidade: um estudo de RMf usando recordações autobiográficas

    Directory of Open Access Journals (Sweden)

    Carlos T. Cerqueira

    2010-06-01

    Full Text Available OBJECTIVE: Despite the relevance of irritability emotions to the treatment, prognosis and classification of psychiatric disorders, the neurobiological basis of this emotional state has been rarely investigated to date. We assessed the brain circuitry underlying personal script-driven irritability in healthy subjects (n = 11 using functional magnetic resonance imaging. METHOD: Blood oxygen level-dependent signal changes were recorded during auditory presentation of personal scripts of irritability in contrast to scripts of happiness or neutral emotional content. Self-rated emotional measurements and skin conductance recordings were also obtained. Images were acquired using a 1,5T magnetic resonance scanner. Brain activation maps were constructed from individual images, and between-condition differences in the mean power of experimental response were identified by using cluster-wise nonparametric tests. RESULTS: Compared to neutral scripts, increased blood oxygen level-dependent signal during irritability scripts was detected in the left subgenual anterior cingulate cortex, and in the left medial, anterolateral and posterolateral dorsal prefrontal cortex (cluster-wise p-value OBJETIVO: Apesar da relevância de emoções de irritabilidade para o tratamento, prognóstico e classificação dos transtornos psiquiátricos, as bases neurobiológicas deste tipo de estado emocional foram raramente investigadas até hoje. Este estudo avaliou os circuitos cerebrais subjacentes à irritabilidade induzida por scripts pessoais em voluntários saudáveis (n = 11 usando ressonância magnética funcional. MÉTODO: Mudanças no sinal dependente do nível de oxigenação sanguínea (blood-oxygen level dependent signal foram registradas durante a apresentação por via auditiva de scripts pessoais de irritabilidade em contraste com scripts de felicidade ou de conteúdo emocional neutro. Escores em escalas de autoavaliação emocional e medidas de condutância da

  6. Untersuchung der Nitridierung V/Al-intermetallischer Phasen

    OpenAIRE

    Lewalter, Hartmut Berthold

    2004-01-01

    Schichten V/Al-Intermetallischer Phasen und Schichten aus V(Al) (Schichtdicken 150- 300 nm) wurden durch Interdiffusion von V/Al- und V5Al8/V-Mehrfachschichten bei 400-800°C im Vakuum bei 3 x 10-8 mbar hergestellt. Des Weiteren wurden V5Al8-Schichten durch Sputtern einer V5Al8-Legierung erzeugt. Die Gesamtstöchiometrie der Schichten lag zwischen Al0,86V0,14 und Al0,19V0,81. Als Substrat dienten einkristalline (012) Saphirwafer. Die V/Al-Intermetallischen Phasen und V(Al) wurden im RTP-System ...

  7. Response to Signorovitch et al.

    Science.gov (United States)

    Flot, Jean-François; Debortoli, Nicolas; Hallet, Bernard; Van Doninck, Karine

    2016-08-22

    Signorovitch et al.[1] comment that an Oenothera-like meiosis [2] could produce a pattern similar to what we observed in our study of natural isolates of the bdelloid rotifer Adineta vaga, which we attributed to horizontal gene transfers (HGTs) [3]. Indeed, our HGT hypothesis appears at first sight difficult to conciliate with their observation of a congruent pattern of allele sharing at four large loci possibly located on different chromosomes [4]. However, one might imagine conditions under which massive horizontal gene transfer between bdelloid individuals could produce such a pattern, notably if the individuals involved had previously lost most of their heterozygosity because of their exposure to frequent desiccation (which produces DNA double-strand breaks [5]). In the published A. vaga genome the loss of heterozygosity due to large-scale gene conversion events or break-induced replication covers only about 10% of the genome [6], but this percentage may be much higher in environmental isolates that often experience dessication. Besides, if an Oenothera-like mode of meiosis occurs in bdelloids frequently enough to be detected in a single sampling of 29 individuals (as in [4]), one would expect males and meiosis to be observed at least occasionally, and instances of congruent allele sharing across loci should turn up frequently in genetic surveys. This was not the case in [3]: among the 82 A. vaga individuals sequenced for four nuclear markers, no trio of individuals presented congruent patterns of shared sequences at different loci. For these reasons, and in the absence of any direct evidence for an Oenothera-like meiosis in bdelloids, we still consider inter-bdelloid HGTs a more parsimonious explanation for our results. PMID:27554651

  8. Atomic structure and oxygen deficiency of the ultrathin aluminium oxide barrier in Al/AlOx/Al Josephson junctions.

    Science.gov (United States)

    Zeng, Lunjie; Tran, Dung Trung; Tai, Cheuk-Wai; Svensson, Gunnar; Olsson, Eva

    2016-01-01

    Al/AlOx/Al Josephson junctions are the building blocks of a wide range of superconducting quantum devices that are key elements for quantum computers, extremely sensitive magnetometers and radiation detectors. The properties of the junctions and the superconducting quantum devices are determined by the atomic structure of the tunnel barrier. The nanoscale dimension and disordered nature of the barrier oxide have been challenges for the direct experimental investigation of the atomic structure of the tunnel barrier. Here we show that the miniaturized dimension of the barrier and the interfacial interaction between crystalline Al and amorphous AlOx give rise to oxygen deficiency at the metal/oxide interfaces. In the interior of the barrier, the oxide resembles the atomic structure of bulk aluminium oxide. Atomic defects such as oxygen vacancies at the interfaces can be the origin of the two-level systems and contribute to decoherence and noise in superconducting quantum circuits. PMID:27403611

  9. Band edge modulation and interband optical transition in AlN:MgAl-ON nanotubes

    International Nuclear Information System (INIS)

    AlN nanotubes (NTs) have many novel characteristics and great potential applications in electronic and optoelectronic nanodevices. However, little is known about the influence of MgAl-ON co-doping effects on their optical properties. Here, we focus on investigating the electronic structures, clarify the interband optical transition mechanism and give a clear atomic picture for the important electron/hole localization centre in AlN:MgAl-ON NTs using the GGA-1/2 method. We find that the MgAl doping efficiency can be improved effectively due to ON doping in AlN NTs. The MgAl and ON form MgAl-ON defect complex easily along the AlN NT axis (C-axis). The MgAl-ON defect complex can result in a remarkable charge transfer around it and modify the valence band maximum and conduction band minimum significantly. Meanwhile, the MgAl-ON defect complex also forms the important exciton localization centre and effectively enhances the interband radiative recombination rate. Moreover, the light emission/absorption sensitively depends on its polarization. The parallel polarized light (E∥C) is much stronger than the perpendicular one (E⊥C). The MgAl-ON co-doping thus paves a new way for improving the performance of electronic and optoelectronic nanodevices based on AlN NTs. (papers)

  10. The theory of the moon in the al-Zij al-Kamil fi-l-taalim of Ibn al-Ha'im

    OpenAIRE

    Puig i Tàrrech, Roser

    2000-01-01

    Al the beginning of Ihe thirteenth cenrury (60tH I 1204-1205) Abli Muhammad Abd al-Haqq al-Ghafiqi al-lshbiIi known as Ibn al-Ha'im composed his work entitled al-Zi] al-Kamil fi-l-Taalim in honour of the Caliph Abu Abd Allah Muhammad al-Nasir (who reigned from 1199- 1213). All we know of lbn al-Ha'im's live is that he came from Seville and that he appears to have worked in North Africa.

  11. Estudio del mecanismo de reacción durante la refinación de magnesio de aleaciones de aluminio líquidas usando partículas de SiO2

    Directory of Open Access Journals (Sweden)

    Flores, A.

    2008-04-01

    Full Text Available An analysis of the results regarding the permanent contact reaction that occurs between the Mg dissolved in molten aluminum and SiO2 particles is presented. The experiments were carried out at constant temperature and molten metal stirring velocity. In the Scanning Electron Microscope, the crystallographic characteristics of the reaction products were determined using the Electron Backscattered Diffraction Technique, thus allowing to establish the stoichiometry and the mechanism of reaction. The results indicate that the mechanism of reaction is governed by Al, Mg, and Si ions diffusion through the layers of reaction products composed of MgAl2O4 and Al2O3 phases. It was found that during the process the composition of the reaction products changed as the concentration of Mg in the boundary layer diminished.

    Se presentan y discuten los resultados de un estudio acerca de la reacción de contacto permanente que ocurre entre partículas de sílice y el magnesio disuelto en una aleación de aluminio líquida, a temperatura y velocidad de agitación constantes. Se obtuvieron muestras en función del tiempo de contacto, siendo caracterizadas mediante Difracción de Electrones Retrodispersados (EBSD en el Microscopio Electrónico de Barrido. Esto, permitió definir la estructura cristalina de los compuestos que se forman durante las reacciones involucradas y como consecuencia determinar la estequiometría y el mecanismo de reacción. Los resultados indicaron que dicho mecanismo está gobernado por la difusión de los iones de aluminio, magnesio y silicio a través de la porosidad de las capas de MgAl2O4 y Al2O3 que se forman como productos de reacción, encontrándose, además, que la composición de dichos productos cambiaba conforme la concentración de magnesio en la interfase sólido (SiO2-fundido (Al-Mg disminuía.

  12. Effect of Al coating conditions on laser weldability of Al coated steel sheet

    Institute of Scientific and Technical Information of China (English)

    Jung-Han LEE; Jong-Do KIM; Jin-Seok OH; Seo-Jeong PARK

    2009-01-01

    Al coated steel sheets with excellent heat resistance, thermal reflection, and corrosion resistance are widely used in various applications. The laser weldability of the Al coated steel sheet for full penetration welding was reported. The phenomenon caused by intermixed aluminum and behavior of aluminum in the weld were investigated. Al coated steel sheets that have various thickness and coating mass were prepared for laser welding. The effects of parameters such as welding conditions and Al coating conditions were investigated. Al content mixed in the weld after laser welding was evaluated, and then a correlation between the mixed Al and mechanical properties was investigated. The results show that the Al-rich zones which have Fe-Al intermetallic compounds are found in the weld. The intermetallic compounds cause the decreased strength of the weld.

  13. Studies on SiC(p) reinforced Al-Al sub 3 Ni eutectic matrix composites

    International Nuclear Information System (INIS)

    An investigation on processing of Al-5.69wt% Ni eutectic with SiC particulate composites is reported. The intermetallic composites are prepared by elemental powder metallurgy route and sintered at two different temperatures, i.e., 600 degree C and 620 degree C. Results show that the metal matrix was Al-Al sub 3 Ni eutectic. The phase analysis by XRD identified the presence of Al sub 3 Ni and Al as dominant phases together with silicon and Al sub 4 C sub 3 phase as minor phases. The Al sub 4 C sub 3 and Si phases are formed during sintering due to SiC-Al interface reaction. SEM micrographs also reveal the formation of microvoid surrounding the SiC particle

  14. Diana Al-Hadid: Identity and Heritage

    Science.gov (United States)

    Jungerberg, Tom; Smith, Anna; Borsh, Colleen

    2012-01-01

    Diana Al-Hadid's sculptures reflect the many locations, cultures, histories, and mythologies that have shaped her as an artist. In large-scale works which have the appearance of architectural ruins, Al-Hadid employs imagery drawn from many diverse interests including science and technology, history, and literature. She also incorporates images and…

  15. Kus on al-Zarqawi? / Aadu Hiietamm

    Index Scriptorium Estoniae

    Hiietamm, Aadu, 1954-

    2005-01-01

    Suurbritannia nädalalehe Sunday Times andmetel on Iraagi tagaotsituim mässaja, terrorivõrgustiku al Qaeda liitlane Abu-Musab al-Zarqawi pärast USA raketirünnakus haavatasaamist riigist põgenenud

  16. Als je vrienden hebt dan win je

    NARCIS (Netherlands)

    Effing, R. (Robin); Huibers, T. (Theo); Krosse, de L. (Luc)

    2010-01-01

    Als je wint, heb je vrienden’ is een Nederlandse klassieker van Herman Brood en Henny Vrienten. Hiermee werd de gevoelige snaar bloot gelegd dat pas als je hebt gewonnen je vrienden hebt. Rijen dik, echte vrienden. In de politiek werkt het andersom; je moet vrienden (stemmen) hebben, ve

  17. MOSQUE ARCHITECTURE AS A SUSTAINABLE BUILDING IN URBAN (Case Study: Al Markas Al Islamic Mosque Makassar)

    OpenAIRE

    Imriyanti Imriyanti

    2014-01-01

    Abstract Mosque Architecture is a part of Islamic architecture. Mosque should be fused with elements of nature because its function as a place to pray to God who created the universe. Al Markas Al Islamic Makassar mosque is used as a center of Islamic aspirations of the people and the government to accommodate all the activities of moslems in Makassar. Through this function, the provision of Al Markas Al Islamic mosque began from the desire of Islamic societies in Makassar, which want...

  18. High temperature creep behaviour of Al-rich Ti-Al alloys

    Energy Technology Data Exchange (ETDEWEB)

    Sturm, D; Heilmaier, M; Saage, H [Otto von Guericke University Magdeburg, Institute for Materials and Joining Technology, PO Box 4120, D-39016 Magdeburg (Germany); Aguilar, J; Schmitz, G J; Drevermann, A [ACCESS e.V., Intzestrasse 5, D-52072 Aachen (Germany); Palm, M; Stein, F; Engberding, N [Max-Planck-Institut fuer Eisenforschung GmbH, Max-Planck-Str. 1, D-40237 Duesseldorf (Germany); Kelm, K; Irsen, S, E-mail: daniel.sturm@ovgu.d [Stiftung caesar, Electron Microscopy, Ludwig-Erhard-Allee 2, D-53175 Bonn (Germany)

    2010-07-01

    Compared to Ti-rich {gamma}-TiAl-based alloys Al-rich Ti-Al alloys offer an additional reduction of in density and a better oxidation resistance which are both due to the increased Al content. Polycrystalline material was manufactured by centrifugal casting. Microstructural characterization was carried out employing light-optical, scanning and transmission electron microscopy and XRD analyses. The high temperature creep of two binary alloys, namely Al{sub 60}Ti{sub 40} and Al{sub 62}Ti{sub 38} was comparatively assessed with compression tests at constant true stress in a temperature range between 1173 and 1323 K in air. The alloys were tested in the cast condition (containing various amounts of the metastable phases Al{sub 5}Ti{sub 3} and h-Al{sub 2}Ti) and after annealing at 1223 K for 200 h which produced (thermodynamically stable) lamellar {gamma}-TiAl + r-Al{sub 2}Ti microstructures. In general, already the as-cast alloys exhibit a reasonable creep resistance at 1173 K. Compared with Al{sub 60}Ti{sub 40}, both, the as-cast and the annealed Al{sub 62}Ti{sub 38} alloy exhibit better creep resistance up to 1323 K which can be rationalized by the reduced lamella spacing. The assessment of creep tests conducted at identical stress levels and varying temperatures yielded apparent activation energies for creep of Q = 430 kJ/mol for the annealed Al{sub 60}Ti{sub 40} alloy and of Q = 383 kJ/mol for the annealed Al{sub 62}Ti{sub 38} material. The latter coincides well with that of Al diffusion in {gamma}-TiAl, whereas the former can be rationalized by the instability of the microstructure containing metastable phases.

  19. Corrosion Studies of 2195 Al-Li Alloy and 2219 Al Alloy with Differing Surface Treatments

    Science.gov (United States)

    Danford, M. D.; Mendrek, M. J.

    1998-01-01

    Corrosion studies of 2195 Al-Li and 2219 Al alloys have been conducted using the scanning reference electrode technique (SRET) and the polarization resistance (PR) technique. The SRET was used to study corrosion mechanisms, while corrosion rate measurements were studied with the PR technique. Plates of Al203 blasted, soda blasted and conversion coated 2219 Al were coated with Deft primer and the corrosion rates studied with the EIS technique. Results from all of these studies are presented.

  20. Assessment of the al corner of the ternary Al-Fe-Si system

    OpenAIRE

    Eleno, Luiz; Vezelý, Josef; Sundman, Bo; Cieslar, Miroslav; Lacaze, Jacques

    2010-01-01

    The present work provides a review of the information available on the Al-rich corner of the Al-Fe-Si system as well as a CALPHAD type assessment making use of the COST 507 database as a starting point. The description of the intermetallic compounds has been modified to account for substitution of Al and Si in the ternary Al-Fe-Si system and to take new experimental information into account.

  1. The annealing behaviour of hydrogen implanted into Al metal and Al-Si alloy

    International Nuclear Information System (INIS)

    In the present experiment, we have investigated how defects and elements as additive play a role as trap site by observing the annealing behaviour of hydrogen implanted into Al and Al-Si alloy. It was found that hydrogen is trapped as molecules in grain boundaries of Si in Al. (author)

  2. Shadow evaporation of epitaxial Al/Al2O3/Al tunnel junctions on sapphire utilizing an inorganic bilayer mask

    OpenAIRE

    Welander, Paul B.; Bolkhovsky, Vladimir; Weir, Terence J.; Gouker, Mark A.; Oliver, William D.

    2012-01-01

    This letter describes a new inorganic shadow mask that has been employed for the evaporation of all-epitaxial Al/Al2O3/Al superconducting tunnel junctions. Organic resists that are commonly used for shadow masks and other lift-off processes are not compatible with ultra-high vacuum deposition systems, and they can break down at even moderately elevated temperatures. The inorganic mask described herein does not suffer these same shortcomings. It was fabricated from a Ge/Nb bilayer, comprising ...

  3. Realidad virtual, destinada al desarrollo de aplicaciones para las diferentes áreas del conocimiento

    Directory of Open Access Journals (Sweden)

    CARLOS AREVALO

    2006-01-01

    Full Text Available Con el presente artículo se quiere dar a conocer un proyecto realizado por el grupo de investigación en realidad virtual de la Universidad Tecnológica de Pereira, el cual pretende utilizar la realidad virtual y sus ventajas, aplicadas a las diferentes áreas del conocimiento manejadas actualmente en la universidad, así como motivar su estudio e investigación a través del laboratorio que el grupo planea implementar, y en donde la comunidad universitaria podrá experimentar, investigar y desarrollar aplicaciones como mundos o ambientes virtuales, usando VRML o cualquiera de los diferentes programas de modelado tridimensional, para posteriormente ser aplicados en el área donde se requiera, usando dispositivos 3D.

  4. Japanese version of the ALS-FTD-Questionnaire (ALS-FTD-Q-J).

    Science.gov (United States)

    Watanabe, Yasuhiro; Beeldman, Emma; Raaphorst, Joost; Izumi, Yuishin; Yoshino, Hiide; Masuda, Michihito; Atsuta, Naoki; Ito, Satoru; Adachi, Tadashi; Adachi, Yoshiki; Yokota, Osamu; Oda, Masaya; Hanashima, Ritsuko; Ogino, Mieko; Ichikawa, Hiroo; Hasegawa, Kazuko; Kimura, Hideki; Shimizu, Toshio; Aiba, Ikuko; Yabe, Hayato; Kanba, Makoto; Kusumi, Kimiyoshi; Aoki, Tetsuya; Hiroe, Yu; Watanabe, Hirohisa; Nishiyama, Kazutoshi; Nomoto, Masahiro; Sobue, Gen; Nakashima, Kenji

    2016-08-15

    Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) share common clinical, genetic and neuropathological features. Some ALS patients have behavioral/personality changes, which could result in significant obstacles in the care provided by family members and caregivers. An easy screening tool would contribute greatly to the evaluation of these symptoms. We translated the ALS-FTD-Questionnaire, developed in the Netherlands, into Japanese (ALS-FTD-Q-J) and examined the clinimetric properties (internal consistency, construct and clinical validity). Patients with ALS and/or behavioral variant FTD (bvFTD) were evaluated alongside healthy controls in this multicenter study. All ALS patients, regardless of bvFTD status, were further evaluated by the frontal behavioral inventory (FBI) and for frontal/executive function, cognition, anxiety/depression, and motor functions. Data from 146 subjects were analyzed: ALS (92), ALS-bvFTD (6), bvFTD (16), and healthy controls (32). The internal consistency of the ALS-FTD-Q-J was good (Cronbach α=0.92). The ALS-FTD-Q-J showed construct validity as it exhibited a high correlation with the FBI (r=0.79). However, correlations were moderate with anxiety/depression and low with cognitive scales, in contrast to the original report, i.e. a moderate correlation with cognition and a low correlation with anxiety/depression. The ALS-FTD-Q-J discriminated ALS patients from (ALS-)bvFTD patients and controls. Thus, the ALS-FTD-Q-J is useful for evaluating Japanese ALS/FTD patients. PMID:27423564

  5. DISTINGSI DAN DIASPORA TASAWUF ABÛ AL-HASAN AL-SHÂDHILÎ

    OpenAIRE

    Saifulah Saifulah

    2015-01-01

    This article discusses Shâdhilîyah, one of the most recognized sufi orders, which possesses quite distinct aspects in the conception of its mystical teachings. This sufi order was founded by Abû al-H}asan al-Shâdhilî, a sufi who has moderate and open view of the worldly life. Al-Shâdhilî explained about how a sufi should behave towards and deal with worldly matters. Although al-Shâdhilî asserted that a person who practice tasawwuf should not pay more adoration on the worldly matters (hubb al-...

  6. The influence of Al content on the Zener relaxation of Fe-Al alloys

    International Nuclear Information System (INIS)

    The effect of Al content on the Zener relaxation peak of annealed Fe-Al alloys has been investigated using a computer-controlled automatic inverted torsion pendulum through the method of free decay and forced vibration. It has been shown that alloys with medium Al contents show strong relaxation while lower or higher Al contents lead to relatively weak Zener relaxation peaks. The Zener relaxation in Fe-Al alloys originates from the next-nearest-neighbour atom pairs and their interaction rather than the nearest-neighbour atom pairs. The latter may not produce Zener relaxation because of the ordered structure, which suppresses Zener relaxation

  7. Magnetism in bcc Fe-Al alloy

    Energy Technology Data Exchange (ETDEWEB)

    Elzain, M.E. [Sultan Qaboos Univ., Al-Khod (Oman). Dept. of Phys.; Yousif, A.A. [Sultan Qaboos Univ., Al-Khod (Oman). Dept. of Phys.

    1994-11-01

    The magnetic moment {mu}, hyperfine field B{sub hf} and isomer shift IS at the Fe site in bcc Fe-Al alloys were calculated from first principle. Contrary to the belief that Al atoms reside in the iron lattice as magnetic holes, it was found that the local magnetic moment of Fe is decreased when Al is at a nearest neighbour site (NN), while it increases if Al is at a next-nearest neighbour site (NNN). Consequently, the average {mu} per Fe atom was found to be, initially, independent of Al content. Assuming a linear dependence of {mu}{sub Fe} on the number of Al atoms at NN and NNN sites, we calculated the average {mu}, which was found to agree with experimental results of cold worked alloys for disordered Fe-Al alloy. On the other hand, antiferromagnetic coupling appears in the CsCl ordered structures. The average B{sub hf} was also calculated and compared to experimental data and the trends in the IS are considered. (orig.)

  8. Comparative study on interface and bulk charges in AlGaN/GaN metal-insulator-semiconductor heterostructures with Al2O3, AlN, and Al2O3/AlN laminated dielectrics

    Science.gov (United States)

    Zhu, Jie-Jie; Ma, Xiao-Hua; Chen, Wei-Wei; Hou, Bin; Xie, Yong; Hao, Yue

    2016-05-01

    In this paper, the interface and bulk charges in AlGaN/GaN metal-insulator-semiconductor (MIS) heterostructures with AlN, Al2O3, and Al2O3/AlN laminated dielectrics were studied. In situ plasma pretreatment resulted negligible interface trap states and voltage hysteresis. The fixed charge density at Al2O3/AlN (or Al2O3/barrier) interface was estimated to be 1.66 × 1013 cm-2 by using flat-band voltage shift, and the oxide bulk charge concentration was 2.86 × 1017 cm-3. The interface charge density at other interfaces were at the order of 1011 cm-2. Simulation results using the above charge density/concentration indicated that Al2O3/AlN interface fixed charges dominated the dielectric-related voltage shift in AlGaN/GaN MIS heterostructures, which caused a large voltage shift of -3 V with 10 nm Al2O3 thickness, while the flat-band voltage variety resulting from other types of charges was within 0.1 V.

  9. Tracing Al Shabaab’s Decision to Cooperate with Al Qaeda in Somalia (2008

    Directory of Open Access Journals (Sweden)

    Adlini Ilma Ghaisany Sjah

    2014-02-01

    Full Text Available 'Al Shabaab, a Somali insurgent with predominantly nationalistic causes (alongside transnational [global Jihad] and Islamic goals made the choice to fight on behalf of Al Qaeda in 2008. The decision to do so contrasted with Al Shabaab’s previous behaviour of actively denying cooperation and distancing itself from Al Qaeda. This study aims to uncover factors that contributed to Al Shabaab’s decision through the use of process-tracing. The results show that Al Shabaab’s declaration of cooperation with Al Qaeda in August 2008 was brought about by a series of events that traced back to four factors: public reactions to the implementation of a Salafi ideology, the shift to a radical leadership, Al Shabaab’s inability to maintain stability in areas under its control and its increasing attacks by Al Shabaab on the Somali public. Al Shabaab pursued cooperation with Al Qaeda after realizing that their nationalistic preference was no longer achievable in the near future.' ' '

  10. Optical characterization of Al- and N-polar AlN waveguides for integrated optics

    Science.gov (United States)

    Rigler, Martin; Buh, Jože; Hoffmann, Marc P.; Kirste, Ronny; Bobea, Milena; Mita, Seiji; Gerhold, Michael D.; Collazo, Ramon; Sitar, Zlatko; Zgonik, Marko

    2015-04-01

    Dispersion of the extraordinary and ordinary refractive indices of Al- and N-polar AlN waveguides is measured by multiple angle-of-incidence and spectroscopic ellipsometry techniques. The polarity-controlled AlN layers are grown by metal-organic chemical vapor deposition on (0001)-sapphire substrates. Taking into consideration the different surface morphologies of the Al- and N-polar AlN waveguides, we propose two optical models to describe the measured ellipsometry data. The results indicate that there is no difference between the refractive indices of the AlN grown in opposite directions, which confirms the potential of the AlN lateral polar structures for use in nonlinear optical applications based on quasi phase matching.

  11. Oxidation of Al2O3 continuous fiber-reinforced/NiAl composites

    Science.gov (United States)

    Doychak, J.; Nesbitt, J. A.; Noebe, R. D.; Bowman, R. R.

    1992-01-01

    The 1200 C and 1300 C isothermal and cyclic oxidation behavior of Al2O3 continuous fiber-reinforced/NiAl composites were studied. Oxidation resulted in formation of Al2O3 external scales in a similar manner as scales formed on monolithic NiAl. The isothermal oxidation of an Al2O3/NiAl composite resulted in oxidation of the matrix along the fiber/matrix interface near the fiber ends. This oxide acted as a wedge between the fiber and the matrix, and, under cyclic oxidation conditions, led to further oxidation along the fiber lengths and eventual cracking of the composite. The oxidation behavior of composites in which the Al2O3 fibers were sputter coated with nickel prior to processing was much more severe. This was attributed to open channels around the fibers which formed during processing, most likely as a result of the diffusion of the nickel coating into the matrix.

  12. A Rechargeable Al/S Battery with an Ionic-Liquid Electrolyte.

    Science.gov (United States)

    Gao, Tao; Li, Xiaogang; Wang, Xiwen; Hu, Junkai; Han, Fudong; Fan, Xiulin; Suo, Liumin; Pearse, Alex J; Lee, Sang Bok; Rubloff, Gary W; Gaskell, Karen J; Noked, Malachi; Wang, Chunsheng

    2016-08-16

    Aluminum metal is a promising anode material for next generation rechargeable batteries owing to its abundance, potentially dendrite-free deposition, and high capacity. The rechargeable aluminum/sulfur (Al/S) battery is of great interest owing to its high energy density (1340 Wh kg(-1) ) and low cost. However, Al/S chemistry suffers poor reversibility owing to the difficulty of oxidizing AlSx . Herein, we demonstrate the first reversible Al/S battery in ionic-liquid electrolyte with an activated carbon cloth/sulfur composite cathode. Electrochemical, spectroscopic, and microscopic results suggest that sulfur undergoes a solid-state conversion reaction in the electrolyte. Kinetics analysis identifies that the slow solid-state sulfur conversion reaction causes large voltage hysteresis and limits the energy efficiency of the system. PMID:27417442

  13. Magnetic properties and crystal structure of HoNiAl and UNiAl hydrides

    International Nuclear Information System (INIS)

    The effect of hydrogenation on the magnetic properties and crystal structure of 4f and 5f intermetallics was studied on HoNiAlH2.0, UNiAlH2.3 and UNiAlD2.1. The incorporation of hydrogen into HoNiAl leads to a decrease of the magnetic ordering temperature from 13 to 6 K, while it increases from 19 K to values in the range 90-100 K in the UNiAl-H system. The crystal lattices of all compounds are anisotropically expanded. Moreover, the crystal symmetry is lowered to orthorhombic in HoNiAlH2.0, but remains hexagonal for UNiAlH(D)x. Three different deuterium positions were found for both compounds. (c) 2000 American Institute of Physics

  14. AlON粉体的合成%Synthesis of AlON Powder

    Institute of Scientific and Technical Information of China (English)

    赵小军; 茹红强; 张宁; 孙有政

    2009-01-01

    以α-Al_2O_3和AlN为原料,利用高温固相反应在氮气气氛下常压合成了AlON粉体.研究了成分配比、合成温度、保温时间对合成AlON粉体含量的影响,并通过热分析测试了合成过程热流和质量的变化.结果表明,当原料Al_2O_3和AlN的质量比为81:18、合成工艺为1750 ℃, 2 h时,得到AlON相的含量达到95%以上.

  15. Adherencia al tratamiento en la esquizofrenia

    OpenAIRE

    Ruiz Manrique, Olatz

    2015-01-01

    [Es]La adherencia al tratamiento es un problema real en los pacientes esquizofrénicos, que dificulta su inserción en la sociedad y puede ocasionarles graves repercusiones médicas. Por ello, el objetivo de esta revisión es valorar la eficacia de las intervenciones psicoeducacionales con la ayuda del personal sanitario y/o familiares, en la adherencia al tratamiento de los pacientes esquizofrénicos. Se realizó una revisión sistemática para dar respuesta al objetivo planteado, analizando las res...

  16. Amyotrofinen lateraaliskleroosi (ALS) ja potilaan ohjaus

    OpenAIRE

    Korkeaniemi, Lotta; Kaakinen, Leena

    2009-01-01

    Saimme opinnäytetyömme toimeksiantona Hyvinkään sairaalan sisätautien vuodeosastolta. Tavoitteena oli luoda ALS potilaille potilasopas trakeostomiasta ja sen kanssa elämisestä. Oppaan tarkoituksena on auttaa ALS potilaita päättämään, kuinka pitkälle he haluavat viedä heidän hengitystukihoitonsa. Samalla hoitajat saavat tuki materiaalia, jonka avulla he voivat käydä läpi hengitystukihoitoja ja erityisesti trakeostomiaan liittyviä asioita. ALS eli amyotrofinen lateraaliskleroosi on tahdona...

  17. Suspected variables among Al Sufi stars.

    Science.gov (United States)

    Hoffleit, D.

    In the tenth century Al Sufi compiled a catalogue of some 1100 stars. J.E. Gore, around 1900, wrote extensively on the magnitudes of these stars. On intercomparing them with a few other catalogues, Gore surmised that some 38 stars appeared to show secular variations. Here all the Al Sufi magnitudes have been compared with numerous additional sources, but smooth secular variations are not substantiated although some stars seem to have undergone comparatively sudden changes after about 1600. About 70 Al Sufi stars are now named or suscpected variable stars, but nearly all with amplitudes under 0.3 V.

  18. TAFSIR SEMANTIK TERHADAP SURAT AL-KAFIRUN

    Directory of Open Access Journals (Sweden)

    Imam Muslimin

    2011-10-01

    Full Text Available The problems about the reading of al-Qur’an is always interesting to be discussed, in which the use of Arabic includes sound or ‘nash’ is acrucial factor to understand the implicit meaning of the Arabic-written texts. Al-Qur’an discusses problem based on the society’s culture. Al-Kafirun discusses not only about the normative theology but more about sociological contexts in which it tends to show transparency, fight against fanaticism and regionalism. And all of the will bring to the first process of the making of the text meaning to the situational context that creates them.

  19. Linija za transport Al-polizdelkov

    OpenAIRE

    Capl, Žiga

    2012-01-01

    V diplomski nalogi je predstavljena linija za transport Al-polizdelkov, ki je sestavljena iz dveh verižnih transporterjev in dveh manipulatorjev. Omenjeni transporterji morajo transportirati Al-polizdelke od sprejemnega mesta do poti v stiskalnico. V okviru diplomskega dela smo opravili analizo obstoječega ogrodja z naklonom, linije za transport Al-polizdelkov in podali možne rešitve za novo učinkovitejšo izvedbo. Na podlagi tehnično-tehnoloških zahtev smo izbrali najprimernejšo rešitev i...

  20. Characterization of AlInN/AlN/GaN Heterostructures with Different AlN Buffer Thickness

    Science.gov (United States)

    Çörekçi, S.; Dugan, S.; Öztürk, M. K.; Çetin, S. Ş.; Çakmak, M.; Özçelik, S.; Özbay, E.

    2016-07-01

    Two AlInN/AlN/GaN heterostructures with 280-nm- and 400-nm-thick AlN buffer grown on sapphire substrates by metal-organic chemical vapor deposition (MOCVD) have been investigated by x-ray diffraction (XRD), atomic force microscopy (AFM), photoluminescence (PL) and Hall-effect measurements. The symmetric (0002) plane with respect to the asymmetric (10bar{1}2) plane in the 280-nm-thick AlN buffer has a higher crystal quality, as opposed to the 400-nm-thick buffer. The thinner buffer improves the crystallinity of both (0002) and (10bar{1}2) planes in the GaN layers, it also provides a sizeable reduction in dislocation density of GaN. Furthermore, the lower buffer thickness leads to a good quality surface with an rms roughness of 0.30 nm and a dark spot density of 4.0 × 108 cm-2. The optical and transport properties of the AlInN/AlN/GaN structure with the relatively thin buffer are compatible with the enhancement in its structural quality, as verified by XRD and AFM results.

  1. Evolution of ConAl clusters and chemisorption of hydrogen on ConAl clusters

    International Nuclear Information System (INIS)

    The growth behavior of ConAl (n = 1–15) and the chemisorptions of hydrogen on the ground state geometries have been studied using the density functional theory (DFT) within the generalized gradient approximation (GGA). The growth pattern for ConAl is Al-substituted Con+1 clusters, and it keeps the similar frameworks of the most stable Con+1 clusters except for n = 2, 3, and 6. The Al atom substitutes the surface atom of the Con+1 clusters for n ≤ 13. Starting from n = 14, the Al atom completely falls into the center of the Co-frame. The dissociation energy, the second-order energy differences, and the HOMO–LUMO gaps indicate that the magic numbers of the calculated ConAl clusters are 7, 9, and 13, corresponding to the high symmetrical structures. To my knowledge, this is the first time that a systematic study of chemisorption of hydrogen on cobalt aluminum clusters. The twofold bridge site is identified to be the most favorable chemisorptions site for one hydrogen adsorption on ConAl (n = 1–6, 8, 10), and two hydrogen adsorption on ConAl (n = 1–7), while threefold hollow site is preferred for one hydrogen adsorption on ConAl (n = 7, 9, 11–15) and two hydrogen adsorption on ConAl (n = 8–10, 12–15) clusters. The ground state structure of two hydrogen adsorption on Co11Al is exceptional. In general, the binding energy of both H and 2H of ConAl (n = 1–12) is found to increase with the cluster size. And the result shows that large binding energies of the hydrogen atoms and large fragmentation energies for Co11AlH and Co12AlH make these species behaving like magic clusters.

  2. Wali Allah menurut al-Hakim al-Tirmidzi dan Ibnu Taimiyyah

    Directory of Open Access Journals (Sweden)

    Lilik Mursito

    2015-12-01

    Full Text Available The discussion about wali presented in the early time on the hand of al-Hakim al Tirmidzi, which reaps number of responses from Muslim scholar because of his misleading. One of them is Ibn Taimiyyah. Al-Hakim and Ibn Taymiyyah have their own view about wali with several distinctions. In the definition of wali, al-Hakim al-Tirmidzi used more general language than Ibn Taimiyyah, as well as characteristics, how to be wali, the classification, concept of karamah, and the concept of khatm al-awliya’. According to writer, al-Hakim al-Tirmidzi’s view about wali able to deepen our understanding about Sufism, meanwhile Ibn Taimiyyah’s view will led us to comprehend Sufism from modernist point of view. This paper conclude that: both of figures seen that wali of Allah are the servants submissive and obedient in running His command; according to al-Hakim al Tirmidzi, degree of wali can be reached purely from Allah’s bounty and the effort of servants themselves, while Ibn Taimiyyah seen that the degree could be reached in the way of faith and piety of the servant; al-Hakim al-Tirmidzi seen that karamah is the most urgent for wali, while Ibn Taimiyyah did not; al-Hakim al-Tirmidzi utilized the quality of deeds to measure the best people and purity of heart to measure the best wali, while Ibn Taymiyyah utilized the quality of deeds as the assessment standard to measure best people and wali.

  3. Hydrometeor and latent heat profiles of tropical cyclones Conson, Ivan and Catarina using PR/TRMM data Perfis de hidrometeoros e de calor latente dos ciclones tropicais Conson, Ivan e Catarina usando dados do PR/TRMM

    Directory of Open Access Journals (Sweden)

    Marcelo Barbio Rosa

    2010-06-01

    Full Text Available ABSTRACT Microphysical and thermodynamical features of two tropical systems, namely Hurricane Ivan and Typhoon Conson, and one sub-tropical, Catarina, have been analyzed based on space-born radar PR measurements available on the TRMM satellite. The procedure to classify the reflectivity profiles followed the Heymsfield et al (2000 and Steiner et al (1995 methodologies. The water and ice content have been calculated using a relationship obtained with data of the surface SPOL radar and PR in Rondonia State in Brazil. The diabatic heating rate due to latent heat release has been estimated using the methodology developed by Tao et al (1990. A more detailed analysis has been performed for Hurricane Catarina, the first of its kind in South Atlantic. High water content mean value has been found in Conson and Ivan at low levels and close to their centers. Results indicate that hurricane Catarina was shallower than the other two systems, with less water and the water was concentrated closer to its center. The mean ice content in Catarina was about 0.05 g kg-1 while in Conson it was 0.06 g kg-1 and in Ivan 0.08 g kg-1. Conson and Ivan had water content up to 0.3 g kg-1 above the 0ºC layer, while Catarina had less than 0.15 g kg-1. The latent heat released by Catarina showed to be very similar to the other two systems, except in the regions closer to the center.No presente trabalho foram analisados as características microfísicas e termodinâmicas de dois sistemas tropicais, o Furacão Ivan e o Tufão Conson, e um sub-tropical, Catarina, a partir de medições feitas com o radar PR a bordo do satélite TRMM. Na análise, os perfis de refletividade foram classificados conforme as técnicas de Heymsfield et al (2000 e Steiner et al (1995 e em seguida foram calculados os conteúdos de água e gelo, a partir de uma relação obtida no Estado de Rondônia (Brasil. Com estes perfis calculou-se a taxa de aquecimento diabático devido a liberação de calor

  4. In Situ Fabrication of AlN Coating by Reactive Plasma Spraying of Al/AlN Powder

    Directory of Open Access Journals (Sweden)

    Mohammed Shahien

    2011-10-01

    Full Text Available Reactive plasma spraying is a promising technology for the in situ formation of aluminum nitride (AlN coatings. Recently, it became possible to fabricate cubic-AlN-(c-AlN based coatings through reactive plasma spraying of Al powder in an ambient atmosphere. However, it was difficult to fabricate a coating with high AlN content and suitable thickness due to the coalescence of the Al particles. In this study, the influence of using AlN additive (h-AlN to increase the AlN content of the coating and improve the reaction process was investigated. The simple mixing of Al and AlN powders was not suitable for fabricating AlN coatings through reactive plasma spraying. However, it was possible to prepare a homogenously mixed, agglomerated and dispersed Al/AlN mixture (which enabled in-flight interaction between the powder and the surrounding plasma by wet-mixing in a planetary mill. Increasing the AlN content in the mixture prevented coalescence and increased the nitride content gradually. Using 30 to 40 wt% AlN was sufficient to fabricate a thick (more than 200 µm AlN coating with high hardness (approximately 1000 Hv. The AlN additive prevented the coalescence of Al metal and enhanced post-deposition nitriding through N2 plasma irradiation by allowing the nitriding species in the plasma to impinge on a larger Al surface area. Using AlN as a feedstock additive was found to be a suitable method for fabricating AlN coatings by reactive plasma spraying. Moreover, the fabricated coatings consist of hexagonal (h-AlN, c-AlN (rock-salt and zinc-blend phases and certain oxides: aluminum oxynitride (Al5O6N, cubic sphalerite Al23O27N5 (ALON and Al2O3. The zinc-blend c-AlN and ALON phases were attributed to the transformation of the h-AlN feedstock during the reactive plasma spraying. Thus, the zinc-blend c-Al

  5. PEMBARUAN MASLA╩AH DALAM MAQĀ╤ID AL- SHARĪ‘AH: TELAAH HUMANISTIS TENTANG AL-KULLIYYĀT AL-KHAMSAH

    Directory of Open Access Journals (Sweden)

    Zaenuddin Mansyur

    2015-03-01

    Full Text Available Abstract:   In order to answer a variety of issues faced by human being in the current era, such as human rights abuses, social disintegration, and terrorism, the renewal of Islamic law in the level of theoretical and practical aspects is very urgent. This paper aims to examine one of the Islamic legal reform efforts, namely to build a more technical understanding of the concept of ma╣la╪ah contained in the maqā╣īd sharī‘ah, called the al-kulliyat al-khamsah. Therefore, the concept of ma╣la╪ah in ╪if╬ al-dīn is technically defined as al-╪urriyah al-i‘tiqād (freedom of religion and schools; in ╪if╬ al-nafs as al-karamat al-insān (human being breeding; in ╪if╬ al-nasl as ╪if╬ al-usrah (wholeness and harmony of the family; in ╪if╬ al-māl as al-ta╨ammun al-insān (social solidarity , and in ╪if╬ al-‘aql as al-╪uqūq as al-tarbiyāt (increasing human resources quality.Abstrak: Demi menjawab aneka persoalan zaman yang dihadapi manusia era sekarang, seperti penyelewengan terhadap HAM, disintegrasi sosial, dan terorisme, maka pembaharuan hukum Islam dalam tataran teoretis dan praktis urgen dilakukan. Tulisan ini bertujuan untuk mengkaji salah satu upaya pembaruan hukum Islam, yaitu membangun pemahaman yang lebih teknis terhadap konsep ma╣la╪ah yang terkandung dalam maqā╣īd sharī‘ah, yang disebut dengan al-kulliyāt al-khamsah. Oleh karena itu, konsep ma╣la╪ah dalam ╪if╬u al-dīn secara teknis dimaknai sebagai ╪urriyah al-i‘tiqād (kebebasan untuk beragama dan beraliran; dalam ╪if╬u al-nafs sebagai al-karāmāt al-insān (pemuliaan kemanusiaan; dalam ╪if╬u al-nasl sebagai ╪if╬u al-usrah (keutuhan dan keharmonisan keluarga; dalam ╪if╬u al-māl sebagai al-ta╨ammun al-insān (solidaritas sosial; dan dalam ╪if╬u al-‘aql sebagai al-╪uqūq al-tarbiyāt (peningkatan sumber daya manusia.

  6. Voxel-based investigations of regional cerebral blood flow abnormalities in Alzheimer's disease using a single-detector SPECT system Investigações voxel-a-voxel de anormalidades de fluxo sanguíneo cerebral regional na doença de Alzheimer usando equipamento de SPECT de detector único

    Directory of Open Access Journals (Sweden)

    Fabio L. S. Duran

    2007-01-01

    Full Text Available PURPOSE: To evaluate the feasibility of using the Statistical Parametric Mapping (SPM program for an automated, voxel-by-voxel assessment of regional cerebral blood flow (rCBF deficits in Alzheimer's disease (AD subjects relative to age-matched controls studied with a conventional, single-detector SPECT system. METHODS: We used a databank of 99mTc-HMPAO images of 19 patients with a diagnosis of probable AD and 15 elderly healthy volunteers; data were acquired using an Orbiter-Siemens single-detector SPECT system. Using SPM, images were transformed spatially, smoothed (12mm, and the data were compared on a voxel-by-voxel basis with t-tests. RESULTS: There were significant rCBF reductions in AD patients relative to controls involving regions predicted a priori to be affected in AD, namely the left temporal and parietal neocortices, and the right posterior cingulate gyrus (pOBJETIVO: Avaliar a viabilidade de emprego do programa Statistical Parametric Mapping (SPM para investigar de forma automatizada, voxel-a-voxel, a presença de déficits de fluxo sanguíneo cerebral regional (FSCr em pacientes com doença de Alzheimer (DA comparados a sujeitos-controle pareados para idade, usando imagens de SPECT adquiridas com um equipamento convencional de detector único. MÉTODOS: Foi utilizado um banco de imagens adquiridas após injeção de 99mTc-HMPAO em 19 pacientes com diagnóstico provável de DA e 15 voluntários idosos saudáveis, usando um equipamento de SPECT Orbiter-Siemens de detector único. Empregando o programa SPM, as imagens foram transformadas espacialmente, suavizadas (12mm FWHM, e comparadas estatisticamente voxel-a-voxel entre os dois grupos, usando o teste de T. RESULTADOS: Foram identificadas reduções significativas de FSCr nos pacientes com DA comparados aos controles em regiões previstas a priori como afetadas por esta forma de demência, quais sejam os neocórtices temporal e parietal em hemisfério esquerdo e o c

  7. Medida y caracterización de deformaciones usando técnicas geodésicas y de teledetección. Aplicación en volcanología y sismotectónica.

    OpenAIRE

    González Méndez, Pablo José

    2010-01-01

    Programa de doctorado interuniversitario de “Ciencia y tecnología de la ingeniería geodésica y cartográfica”. Memoria presentada por Pablo José González Méndez en el Departamento de Física de la Tierra, Astronomía y Astrofísica - I. (Sección Departamental de Astronomía y Geodesia) para optar al grado de Doctor por la Universidad Complutense de Madrid. Director y tutor, José Fernández Torres.

  8. Un modelo de planificación instruccional usando razonamiento basado en casos en sistemas multi-agente para entornos integrados de sistemas tutoriales inteligentes y ambientes colaborativos de aprendizaje

    OpenAIRE

    JIMÉNEZ BUILES, JOVANI ALBERTO

    2006-01-01

    La Inteligencia Artificial en la Educación es un área interdisciplinar en la que se mezclan investigadores con diversas formaciones y objetivos. Principalmente, trabajan en ella personas interesadas en diferentes campos como: la pedagogía, psicología, informática entre otros. Cada una de ellas aporta desde su perspectiva a la construcción de la disciplina con el propósito de aplicar diversas técnicas al desarrollo de sistemas de enseñanza / aprendizaje de manera inteligente. El término “intel...

  9. Simulación de la hidrogenación de aceite de girasol usando dióxido de carbono supercrítico y cosolvente. Impacto del cosolvente en la seguridad de la planta

    OpenAIRE

    Cuevas Baquero, Daniel

    2008-01-01

    Este proyecto trata la problemática que representa para la sociedad el consumo excesivo de grasas hidrogenadas y sus consecuencias sobre la salud. El consumo de grasas hidrogenadas está presente en la bollería industrial, en las patatas fritas, margarinas, etc. Al hidrogenar las grasas suceden reacciones secundarias no deseadas que dan lugar a productos perjudiciales para el consumo humano, es este punto el que se ha estudiado: el proceso de obtención de margarinas. Se propo...

  10. A DEMODULATOR OF PWM SIGNALS GENERATED FOR A DIGITAL ACCELEROMETER IS DEVELOPED USING A MICROCONTROLLER UN DEMODULADOR DE SEÑALES PWM GENERADAS POR UN ACELERÓMETRO DIGITAL ES DESARROLLADO USANDO UN MICROCONTROLADOR

    Directory of Open Access Journals (Sweden)

    Eduardo Pérez Lobato

    2006-08-01

    Full Text Available This paper presents the use of a microcontroller to demodulate two Pulse Width Modulated (PWM signals which are being generated by a digital accelerometer, to obtain their pulse widths and transmit them serially to a parallel port of a general purpose computer.Esta publicación presenta el uso de un microcontrolador para demodular dos señales PWM que están siendo generadas por un acelerómetro digital, obtener sus anchos y enviarlas en forma serial al puerto paralelo de un computador de propósitos generales.

  11. Localización de faltas en sistemas de distribución de energía eléctrica usando métodos basados en el modelo y métodos basados en el conocimiento

    OpenAIRE

    MORA FLÓREZ, JUAN JOSÉ

    2006-01-01

    La calidad de energía eléctrica incluye la calidad del suministro y la calidad de la atención al cliente. La calidad del suministro a su vez se considera que la conforman dos partes, la forma de onda y la continuidad. En esta tesis se aborda la continuidad del suministro a través de la localización de faltas. Este problema se encuentra relativamente resuelto en los sistemas de transmisión, donde por las características homogéneas de la línea, la medición en ambos terminales y la disponibilid...

  12. Evaluación de siete tipos de vegetales herbáceas cultivadas en acuaponia usando el efluente del cultivo de tilapia (Oreochromis niloticus x O. aureous) en condiciones salobres.

    OpenAIRE

    Campos Pulido, Rosa

    2013-01-01

    Los objetivos de este estudio fueron caracterizar fisicoquímicamente un efluente salobre de cultivo de tilapia en producción comercial, evaluar el crecimiento de siete especies vegetales herbáceas en acuaponia y conocer criterios para seleccionar plantas de acuerdo a las características del efluente. El diseño experimental fue completamente al azar. Los datos se analizaron mediante estadística descriptiva y análisis de varianza. Para comparar las medias de los parámetros evaluados se realizó ...

  13. Implementación de un mantenimiento basado en la condición usando modelado y simulación: caso de estudio de un motor sin-crónico de imanes permanentes

    OpenAIRE

    Quiroga Méndez, Jabid; Oviedo Castillo, Silvia

    2011-01-01

    Este artículo introduce la arquitectura de un CBM (mantenimiento basado en la condición) en una aplicación eléctrica. La detección de fallas de manera oportuna y eficiente constituye uno de los retos más importantes asociados al CBM y el enfoque basado en modelos en el medio para conseguirlo. Un caso de estudio en un motor sincrónico de imanes permanentes (PMSM) es ejecutado para ilustrar cómo el modelado es utilizado en la implementación de un CBM. El monitoreo fue implementado en tiempo rea...

  14. Corrección de atenuación de imágenes PET usando datos de TAC en el escáner para animales pequeños Argus PET/CT

    OpenAIRE

    Vicente, Esther; Udías, Ángel; López Herraiz, Joaquín; Desco, Manuel; Vaquero, Juan José; Udías, José Manuel

    2010-01-01

    Actas de: XXVIII Congreso Anual de la Sociedad Española de Ingeniería Biomédica (CASEIB 2010). Madrid, 24-26 de noviembre de 2010. Existen diversos efectos físicos que degradan la calidad de la imagen PET, como por ejemplo la atenuación que sufren los fotones al atravesar el cuerpo en estudio. Este efecto reduce el número de fotones detectados, pero puede corregirse si se dispone de información anatómica del objeto. En este trabajo se describe la corrección de atenuación basada en una imag...

  15. Pesticides Linked to Raised Risk of ALS

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_158737.html Pesticides Linked to Raised Risk of ALS One toxin ... MONDAY, May 9, 2016 (HealthDay News) -- Exposure to pesticides and other chemicals may increase the risk for ...

  16. Pesticides Linked to Raised Risk of ALS

    Science.gov (United States)

    ... nlm.nih.gov/medlineplus/news/fullstory_158737.html Pesticides Linked to Raised Risk of ALS One toxin ... MONDAY, May 9, 2016 (HealthDay News) -- Exposure to pesticides and other chemicals may increase the risk for ...

  17. Stem Cells Deemed Safe for ALS Patients

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_159627.html Stem Cells Deemed Safe for ALS Patients But further research needed to see if injections into spine would provide any benefit, researchers say To use the sharing features on ...

  18. ALS: Recent Developments from Genetics Studies.

    Science.gov (United States)

    Therrien, Martine; Dion, Patrick A; Rouleau, Guy A

    2016-06-01

    Amyotrophic lateral sclerosis (ALS) is a fatal disorder that is characterized by a progressive degeneration of the upper and lower motor neurons. Most cases appear to be sporadic, but 5-10 % of cases have a family history of the disease. High-throughput DNA sequencing and related genomic capture tools are methodological advances which have rapidly contributed to an acceleration in the discovery of genetic risk factors for both familial and sporadic ALS. It is interesting to note that as the number of ALS genes grows, many of the proteins they encode are in shared intracellular processes. This review will summarize some of the recent advances and gene discovery made in ALS. PMID:27113253

  19. Het Nederlandse bos als vorm van bodemgebruik

    NARCIS (Netherlands)

    Slangen, L.H.G.; Boven, van B.

    1983-01-01

    Behandeling van de oppervlakte en verdeling van het bos en de veranderingen die hierin zijn opgetreden, met de bedrijfsgrootte-struktuur als belangrijke invalshoek daarbij; de rol van de overheid: doeleinden, instrumenten en effekten van het beleid

  20. In situ (Al3Zr + Al2O3np)/2024Al metal matrix composite with novel reinforcement distributions fabricated by reaction hot pressing

    International Nuclear Information System (INIS)

    Highlights: •(Al3Zr + Al2O3np)/2024Al MMC with a novel network distribution was tailored. •Al3Zr and Al2O3np were in situ synthesized at 740 °C using the 2024Al–ZrO2 system. •The effect of sintering parameters on Al3Zr morphology was investigated. •Influence of Al3Zr morphology on tensile properties of the composite was studied. -- Abstract: In situ hybrid (Al3Zr + Al2O3np)/2024Al metal matrix composites with unique controlled reinforcement distributions were fabricated using low energy ball milling and reactive hot pressing. The reaction system between 2024Al and ZrO2 was studied using differential thermal analysis (DTA). In situ formed aluminium oxide (Al2O3) and zirconium tri-aluminide (Al3Zr) with varying morphology and sizes were produced under different fabricating conditions. Al3Zr with varying morphologies such as particle, plate and flakes were observed. With a total 10 vol.% of reinforcements, the composite containing a three-dimensional network of closely spaced in situ synthesized Al3Zr and Al2O3 particles had a YS of 175 MPa and a UTS of 261 MPa, effectively strengthening the 2024Al matrix. The effect of different sintering conditions on the microstructure and tensile properties of the composite was systematically investigated

  1. Hans Freudenthal als docent en collega

    OpenAIRE

    Verhulst, Ferdinand; Verhoef, Nellie

    2010-01-01

    Hans Freudenthal heeft een belangrijke invloed gehad op de ontwikkeling van het basiswiskundeonderwijs. Niet minder belangrijk was zijn activiteit als docent en onderzoeker gedurende tientallen jaren op het Mathematisch Instituut van de Universiteit Utrecht. Hoe waren toen zijn ideeën over onderwijs, hoe was hij als collega en hoe waren zijn colleges? Nellie Verhoef en Ferdinand Verhulst interviewden voormalige collega’s en studenten van Freudenthal.

  2. Effects of Al substitution on goethite formation

    OpenAIRE

    Premoli, Alessandra Maria; Melis, Pietro; Gessa, Carlo Emanuele; Deiana, Salvatore Andrea

    1984-01-01

    Goethites containing up to 32.7 mole % Al were synthesized and characterized through diffractometry, spectrometry, DSC and chemical techniques. Results indicate that crystal growth was favoured or hindered depending on the percentage of aluminum incorporated into the structure. Goethites to which 5-10 mole % Al were initially added crystallized best, as shown by the highest crystallite dimensions calculated from X-ray and Mössbauer analyses, and by the lowest surface areas values. Over suc...

  3. Anerkennung als Voraussetzung gesellschaftlicher und unternehmerischer Teilhabe

    OpenAIRE

    Eurich, Johannes; Brink, Alexander

    2003-01-01

    Angesichts des neuen Phänomens der sozialen Exklusion wird soziale Gerechtigkeit nicht mehr nur über die Verteilung von Gütern hergestellt, vielmehr spielt auch die Ebene der Partizipation eine Rolle. Anerkennung ist eine Grundvoraussetzung für Partizipation. Die Verfasser diskutieren Fragen der Unternehmensethik auf der Dimension der Anerkennung. Sie votieren für ein normatives Stakeholder-Management als freiwillige Verpflichtung, das auch strategischen Anforderungen gerecht werden kann. Als...

  4. Information als Gegenstand von Informationskompetenz. Eine Begriffsanalyse

    OpenAIRE

    Ingold, Marianne

    2011-01-01

    Der Informationsbegriff als zentraler Gegenstand von Informationskompetenz wird in der bibliothekarischen Diskussion in der Regel nicht explizit thematisiert, sondern lässt sich aus Fachliteratur und Bibliothekspraxis nur implizit erschließen. Eine theoretische Beschäftigung mit dem Informationsbegriff ist jedoch unabdingbar, soll das Konzept "Informationskompetenz" auch außerhalb des bibliothekarischen Kontextes verständlich und nutzbar gemacht werden. Im vorliegenden Text, der sich als B...

  5. Plasma nitriding of Al 99.5

    OpenAIRE

    Chen, H. -Y; Stock, H.-R.; Mayr, P.

    1993-01-01

    Aluminium nitride (AlN) is a very interesting ceramic because of its combination of properties such as high thermal stability, high hardness and an unusual combination of high thermal and low electrical conductivity. But it is very difficulty to obtain an AlN layer on the aluminium substrates by thermochemical nitriding process. Since a thin film of aluminium oxide existing on the surface of every aluminium substrate prevents the nitrogen atoms from diffusing into the aluminium lattice. Howev...

  6. Communication Support for People with ALS

    OpenAIRE

    David Beukelman; Susan Fager; Amy Nordness

    2011-01-01

    Almost all people with amyotrophic lateral sclerosis (ALS) experience a motor speech disorder, such as dysarthria, as the disease progresses. At some point, 80 to 9 5 % of people with ALS are unable to meet their daily communication needs using natural speech. Unfortunately, once intelligibility begins to decrease, speech performance often deteriorates so rapidly that there is little time to implement an appropriate augmentative and alternative communication (AAC) intervention; therefore, app...

  7. Performance of the ALS injection system

    International Nuclear Information System (INIS)

    The authors started commissioning the Advanced Light Source (ALS) storage ring on January 11, 1993. The stored beam reached 60 mA on March 24, 1993 and 407 mA on April 9, 1993. The fast pace of storage ring commissioning can be attributed partially to the robust injection system. In this paper they describe the operating characteristics of the ALS injection system

  8. Del latín al rumano

    Directory of Open Access Journals (Sweden)

    Montes Giraldo José Joaquín

    2003-06-01

    Full Text Available

    Marius Sala, Del latín al rumano. Versión española de Valeria Neagu, París, Unión Latina - Bucarest, Univers enciclopedic, 2002. El texto se dirige al lector corriente, no especialista, y por eso el aparato técnico-bibliográfico no se presenta en el curso de la exposición.

  9. Next-generation sequencing of 28 ALS-related genes in a Japanese ALS cohort.

    Science.gov (United States)

    Nakamura, Ryoichi; Sone, Jun; Atsuta, Naoki; Tohnai, Genki; Watanabe, Hazuki; Yokoi, Daichi; Nakatochi, Masahiro; Watanabe, Hirohisa; Ito, Mizuki; Senda, Jo; Katsuno, Masahisa; Tanaka, Fumiaki; Li, Yuanzhe; Izumi, Yuishin; Morita, Mitsuya; Taniguchi, Akira; Kano, Osamu; Oda, Masaya; Kuwabara, Satoshi; Abe, Koji; Aiba, Ikuko; Okamoto, Koichi; Mizoguchi, Kouichi; Hasegawa, Kazuko; Aoki, Masashi; Hattori, Nobutaka; Tsuji, Shoji; Nakashima, Kenji; Kaji, Ryuji; Sobue, Gen

    2016-03-01

    We investigated the frequency and contribution of variants of the 28 known amyotrophic lateral sclerosis (ALS)-related genes in Japanese ALS patients. We designed a multiplex, polymerase chain reaction-based primer panel to amplify the coding regions of the 28 ALS-related genes and sequenced DNA samples from 257 Japanese ALS patients using an Ion Torrent PGM sequencer. We also performed exome sequencing and identified variants of the 28 genes in an additional 251 ALS patients using an Illumina HiSeq 2000 platform. We identified the known ALS pathogenic variants and predicted the functional properties of novel nonsynonymous variants in silico. These variants were confirmed by Sanger sequencing. Known pathogenic variants were identified in 19 (48.7%) of the 39 familial ALS patients and 14 (3.0%) of the 469 sporadic ALS patients. Thirty-two sporadic ALS patients (6.8%) harbored 1 or 2 novel nonsynonymous variants of ALS-related genes that might be deleterious. This study reports the first extensive genetic screening of Japanese ALS patients. These findings are useful for developing genetic screening and counseling strategies for such patients. PMID:26742954

  10. Heterogeneous nucleation of solid Al from the melt by Al 3 Ti : Molecular dynamics simulations

    KAUST Repository

    Wang, Junsheng

    2010-10-27

    It has been known experimentally for some time that Al3 Ti is a powerful nucleant for the solidification of aluminum from the melt; however, a full microscopic understanding is still lacking. To develop this understanding, we have performed molecular dynamics simulations of the nucleation and early stages of growth using published embedded atom method potentials for Al-Ti, but modified by us to stabilize the D 022 structure. We discover that Al3 Ti can indeed be very effective in promoting the growth of solid Al but the manner in which growth takes place depends sensitively on the surface on which the Al nucleates. In particular, complete growth of solid Al from the liquid on the (001) and (110) surfaces of Al3 Ti occurs at a lower temperature than on the (112) surface. This anisotropy agrees with observations in previous experiments. We explain this observation in terms of interfacial energies. On the preferential (111) surface of Al the solid-liquid interfacial energy is highest while the solid-vacuum energy is lowest. Our simulations also show that the extent of ordering taking place in liquid Al close to the Al 3 Ti substrate above the melting point correlates well with the effectiveness of the substrate as a nucleant below the melting temperature: this could provide a computationally efficient scheme to identify good nucleants. © 2010 The American Physical Society.

  11. Al4C3 Hydration Thermochemical Analysis for Burned Carbon-containing Refractories with Al

    Institute of Scientific and Technical Information of China (English)

    YANG Ding'ao; YU Zhiming; FAN Liuwu

    2003-01-01

    In this paper, X-ray diffractogram analysis and SEM observation of Al4 C3 formed at high temperature from carbon-containing refractories with Al have been carried out.Aluminum added to carbon-containing refractories reacts with C(s)to form Al4 C3(s) gradually during heating from 600 ℃ to 1200℃.It is considered that the interlocked structure of Al4 C3 plate crystals promotes the outstanding increase of hot modulus of rupture of carbon-containing refractories with Al. The HMOR of carbon-containing refractories added with Al additive from 0 to 5wt% increases by 2.8 times being from 6.5MPa to 18.2MPa.After a thermochemical calculation for hydration reaction processes of Al4 C3 and H2O(g), the equilibrium partial pressure chart of H2O(g)in H2O-Al4C3-Al(OH)3 system vs various temperatures has been attained . The H2O (g) partial pressure in the air needed for the Al4 C3 hydration reaction is no more than 10~18 atm at the temperature below 120℃.It is considered that the burned carbon-containing refractories with Al is extremely easy to hydrate and the cracking of burned carbon-containing refractories is generated because that the hydration expansion is 2.11 times during transforming from Al4 C3 to Al(OH)3.The fundamental measure against hydration of the refractories is to insulate the refractories from H2O(g)by various means such as pitch impregnation or other sealing materials.

  12. DISTINGSI DAN DIASPORA TASAWUF ABÛ AL-HASAN AL-SHÂDHILÎ

    Directory of Open Access Journals (Sweden)

    Saifulah Saifulah

    2015-09-01

    Full Text Available This article discusses Shâdhilîyah, one of the most recognized sufi orders, which possesses quite distinct aspects in the conception of its mystical teachings. This sufi order was founded by Abû al-H}asan al-Shâdhilî, a sufi who has moderate and open view of the worldly life. Al-Shâdhilî explained about how a sufi should behave towards and deal with worldly matters. Although al-Shâdhilî asserted that a person who practice tasawwuf should not pay more adoration on the worldly matters (hubb al-dunyâ, the person does not have to abhor and leave such lively aspects as wealth and position behind. The most important thing to a sufi, according to al-Shadhili, is how he obeys the requirements of shar‘ by avoiding away from immoral deeds and at the same time recognizing God in his heart (ma‘rifat Allâh. Al-Shâdhilî initiated tasawuf ‘amalî which is affiliated to the Ahl al-Sunnah wa al-Jamâ‘ah school, an Islamic mystical thought that adheres to the principles of sharî‘ah based on the foundation of al-Qur’ân dan H}adîth. The concept of al-Shâdhilî’s tasawuf has been subsequently revealed into the great sufi order spectrum, namely al-Shâdhilîyah, where during its historical development this sufi order has led to the emergence of many branches with different names.Keywords: Shâdhilîyah, open view, hubb al-dunyâ, ma‘rifat Allâh.

  13. Clinical trials for neuroprotection in ALS.

    Science.gov (United States)

    Siciliano, G; Carlesi, C; Pasquali, L; Piazza, S; Pietracupa, S; Fornai, F; Ruggieri, S; Murri, L

    2010-07-01

    Owing to uncertainty on the pathogenic mechanisms underlying motor neuron degeneration in amyotrophic lateral sclerosis (ALS) riluzole remains the only available therapy, with only marginal effects on disease survival. Here we review some of the recent advances in the search for disease-modifying drugs for ALS based on their putative neuroprotective effetcs. A number of more or less established agents have recently been investigated also in ALS for their potential role in neuroprotection and relying on antiglutamatergic, antioxidant or antiapoptotic strategies. Among them Talampanel, beta-lactam antibiotics, Coenzyme Q10, and minocycline have been investigated. Progress has also been made in exploiting growth factors for the treatment of ALS, partly due to advances in developing effective delivery systems to the central nervous system. A number of new therapies have also been identified, including a novel class of compounds, such as heat-shock protein co-inducers, which upregulate cell stress responses, and agents promoting autophagy and mitochondriogenesis, such as lithium and rapamycin. More recently, alterations of mRNA processing were described as a pathogenic mechanism in genetically defined forms of ALS, as those related to TDP-43 and FUS-TLS gene mutations. This knowledge is expected to improve our understanding of the pathogenetic mechanism in ALS and developing more effective therapies. PMID:20406180

  14. Estudo da capacidade de complexação de íons Cu2+ em solução aquosa usando celulose modificada com anidrido succínico e com poliaminas Study of copper removal from aqueous solutions using modified celluloses with succinic anhydride and polyamines

    Directory of Open Access Journals (Sweden)

    Gabriela S. Corti

    2004-12-01

    Full Text Available Nesse trabalho foi realizada a preparação de novos materiais, a partir da celulose, para complexar íons de metais pesados em solução aquosa e assim, descontaminar águas poluídas por tais metais. Na primeira parte foi realizada a modificação química da celulose usando o anidrido succínico. As funções carboxílicas introduzidas no material foram usadas para ancorar poliaminas produzindo-se três celuloses modificadas inéditas. Todos os materiais obtidos foram caracterizados por espectroscopia no infravermelho (IV e submetidos à análise elementar. A segunda parte do trabalho foi constituída da avaliação do poder de adsorção das celuloses modificadas obtidas em relação aos íons Cu2+ em solução aquosa. O estudo foi realizado usando a titulometria, um método analítico tradicional. Os vários materiais mostraram uma capacidade máxima de complexação variando entre 141 e 263 mg de Cu2+ por grama do material modificado. A eficiência na complexação dos íons Cu2+ mostrou-se proporcional ao número de funções aminas introduzidas na celulose.This work describes the preparation of new materials, derived from cellulose, to be used as complexing agents for heavy metal ions in aqueous solutions and, hence, to decontaminate waters polluted by such metals. The first part deals with the chemical modification of the cellulose using succinic anhydride. The carboxylic acid functions introduced in the material were used to anchor polyamines resulting in three novel modified celluloses. The materials obtained were characterized by elemental analysis and infrared spectroscopy (IR. The second part of the work features the evaluation of the adsorption capacity of the modified celluloses in relation to Cu2+ ions in aqueous solutions. The study was accomplished by titration, a traditional analytical method. The various materials showed a maximum complexing capacity ranging from 141 to 263 mg of Cu2+ per gram of the modified material. The

  15. Preliminary results of a high-resolution refractometer using the Hartmann-Shack wave-front sensor: part I Resultados preliminares com refratrômetro de alta resolução, usando sensor de frente de onda de Hartmann-Shack: parte I

    Directory of Open Access Journals (Sweden)

    Luis Alberto Carvalho

    2003-06-01

    Full Text Available In this project we are developing an instrument for measuring the wave-front aberrations of the human eye using the Hartmann-Shack sensor. A laser source is directed towards the eye and its diffuse reflection at the retina generates an approximately spherical wave-front inside the eye. This wave-front travels through the different components of the eye (vitreous humor, lens, aqueous humor, and cornea and then leaves the eye carrying information about the aberrations caused by these components. Outside the eye there is an optical system composed of an array of microlenses and a CCD camera. The wave-front hits the microlens array and forms a pattern of spots at the CCD plane. Image processing algorithms detect the center of mass of each spot and this information is used to calculate the exact wave-front surface using least squares approximation by Zernike polynomials. We describe here the details of the first phase of this project, i. e., the construction of the first generation of prototype instruments and preliminary results for an artificial eye calibrated with different ametropias, i. e., myopia, hyperopia and astigmatism.Neste projeto estamos desenvolvendo instrumento para medidas das aberrações de frente de onda do olho humano usando um sensor Hartmann-Shack. Uma fonte de luz laser é direcionada ao olho e sua reflexão difusa na retina gera frente de onda aproximadamente esférica dentro do olho. Esta frente de onda atravessa os diferentes componentes do olho (humor vítreo, lente, humor aquoso e córnea trazendo informações sobre as aberrações ópticas causadas por estes componentes. No meio externo ao olho existe sistema óptico formado por uma matriz de microlentes e uma câmera CCD. A frente de onda incide nesta matriz e forma um padrão aproximadamente matricial de "spots" no plano do CCD. Algoritmos de processamento de imagens são utilizados para detectar os centróides de cada "spot" e esta informação é utilizada para

  16. Disordered crystal structure of 20H-AlON, Al10O3N8

    International Nuclear Information System (INIS)

    The disordered crystal structure of 20H-AlON (Al10O3N8) was determined by combined use of X-ray powder diffraction and transmission electron microscopy. The title compound is hexagonal with space group P63/mmc (Z=2) and the unit-cell dimensions are a=0.307082(5) nm, c=5.29447(8) nm and V=0.432376(12) nm3. The structural model showed the positional disordering of three of the six Al sites in the unit cell. The reliability indices calculated from the Rietveld method were Rwp=6.97%, S (=Rwp/Re)=1.68, Rp=5.45%, RB=5.13% and RF=4.56%. We interpreted the disordered structure of 20H-AlON as a statistical average of six different types of ordered structural configurations, which are composed of an octahedral [Al(O, N)6] layer and tetrahedral [Al(O, N)4] layers. We demonstrated the high correlations between the hexagonal unit-cell dimensions and the octahedral layer concentrations for AlON and SiAlON polytypoids. - Graphical abstract: Variations of a and c/(nO+nT) with nO/(nO+nT). The a and c are the hexagonal unit-cell dimensions of AlON, SiAlON and AlN. The nO and nT are, respectively, the numbers of octahedral and tetrahedral layers in the unit cells. The unit-cell dimensions in literature are plotted in black plus for AlON and black cross for SiAlON. The unit-cell dimensions of AlN are a=0.3110 nm and c=0.4980 nm. - Highlights: • Crystal structure of Al10O3N8 is determined by laboratory X-ray powder diffraction. • The atom arrangements are represented by the split-atom model. • Six types of ordered atom arrangements are derived from the disordered structure. • Hexagonal unit-cell dimensions changed systematically for AlON and SiAlON compounds

  17. Prinsip Pendidikan Karakter dalam Islam: Studi Komparasi Pemikiran Al-Ghazali dan Burhanuddin Al-Zarnuji

    Directory of Open Access Journals (Sweden)

    Agus Setiawan

    2014-06-01

    Full Text Available The impelemtantion of character education that is done by the Indonesian government recently has been provoked by al-Ghazali and Burhanuddin al-Zarnuji long ago. It was proven by some written thoughts of al-Ghazali and Burhanuddin al-Zarnuji. They were very famous scientists in their era and widely welknown as educational experts who produced some phenomenal thoughts many people use today. Al-Ghazali and Burhanuddin al-Zarnuji lived in the era of Bani Abbasiyah monarchy, but Both of them lived in different era. Al-Ghazali was born first, then Burhanuddin al-Zarnuji. They had different mazhab, al-Ghazali went to the traditional principle of mazhab Syafi’I and Burhanuddin al-Zarnuji went to the modern principle of mazhab Hanafi. The differences, of course, would create a different thought. Still, they might have a similar principle of Islamic character education. The thoughts of character education of al-Ghazali have been poured in the “Ayyuha Walad” focusing to the students’ character building characterized by religiously obedient, skillfull of general and religious knowledge, socially helpful, affectionate, generous, good citizen, and coloring the society. Some applicable thoughts of character education of Ayyuha al-Walad of al-Gazhali to the contemporary education are: the balance of the happiness purposes of the recent life and the life after death, qana’ah and tawakal, affectionate, caring other, patience, honesty, philanthrophy, social works, generousity, democratic, peace makers, and patriotic. Those characters are also directed in the islamic character education nowdays. So that, the thoughts of al-Ghazali positively and responsively are absorbed by the Indonesian government to build the national character widely implementing in the national curriculum based on the local wisdom and the Islamic values. In the end, the students are able to live happily based on the Islamic rules by implementing the good behavior. Similar to the al

  18. Morphology of phase separation in AlN-Al2OC and SiC-AlN ceramics

    International Nuclear Information System (INIS)

    Solid solutions in the AIN-Al2OC and SiC-AlN systems were fabricated by hot-pressing powder mixtures in graphite dies. X-ray diffraction showed the samples to be single phases of 2H structure. The samples were annealed between 1600 degrees and 1900 degrees C for up to 1000 h. In the SiC-AlN system, optical microscopy and X-ray diffraction failed to reveal microstructural or phase changes. However, electron microscopy showed that samples had decomposed. Streaking of diffraction spots occurred along directions orthogonal to [012] planes (∼43 degrees off the c axis), which is approximately the direction along which the elastic energy function is a minimum. The orientation-dependent Young's modulus was also a minimum along this direction. In AlN-Al2OC, optical microscopy and X-ray diffraction indicated the occurrence of decomposition. The precipitates were disk-shaped with [001] orthogonal to the disks. The occurrence of decomposition along the [001] direction suggests that it is the elastically soft direction

  19. Nanocrack-induced leakage current in AlInN/AlN/GaN

    International Nuclear Information System (INIS)

    Here we report on the study of nano-crack formation in Al1−xInxN/AlN/GaN heterostructures, on its association with composition fluctuation and on its local electrical properties. It is shown here that indium segregation at nano-cracks and threading dislocations originating from the non-pseudomorphic AlN interlayer could be the cause of the high reverse-bias gate leakage current of Ni/Au Schottky contacts on Al1−xInxN/AlN/GaN heterostructures and significantly affects the contact rectifying behavior. Segregation of indium around crack tips in Al1−xInxN acting as conductive paths was assessed with conductive atomic force microscopy.

  20. Scattering induced by Al segregation in AlGaN/GaN heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xiwen; Lu, Yanwu, E-mail: ywlu@bjtu.edu.cn [Department of Physics, Beijing Jiaotong University, Beijing 100044 (China); Ji, Dong [School of Electrical, Computer and Energy Engineering, Arizona State University, Tempe, Arizona 85281 (United States)

    2015-08-17

    The effect of Al segregation near dislocations on the mobility of two-dimensional electron gas in AlGaN/GaN heterostructure-based high-electron-mobility transistors was investigated. Exponentially varied composition fluctuation was effective in describing Al segregation near dislocations when calculating scattering behavior. Mobility, which was limited by Al segregation surrounding dislocation lines, was calculated to be in the order of 10{sup 3} cm{sup 2}/Vs to 10{sup 6} cm{sup 2}/Vs. Results indicated that the mobility in AlGaN/GaN heterojunction was enhanced upon the reduction of dislocation density at low temperature. This study contributes to generating higher electron mobility in AlGaN/GaN heterojunctions.

  1. Scattering induced by Al segregation in AlGaN/GaN heterostructures

    International Nuclear Information System (INIS)

    The effect of Al segregation near dislocations on the mobility of two-dimensional electron gas in AlGaN/GaN heterostructure-based high-electron-mobility transistors was investigated. Exponentially varied composition fluctuation was effective in describing Al segregation near dislocations when calculating scattering behavior. Mobility, which was limited by Al segregation surrounding dislocation lines, was calculated to be in the order of 103 cm2/Vs to 106 cm2/Vs. Results indicated that the mobility in AlGaN/GaN heterojunction was enhanced upon the reduction of dislocation density at low temperature. This study contributes to generating higher electron mobility in AlGaN/GaN heterojunctions

  2. 60Co gamma radiation effect on AlGaN//AlN/GaN HEMT devices

    International Nuclear Information System (INIS)

    The testing techniques and experimental methods of the 60Co gamma irradiation effect on AlGaN/AlN/GaN high electron mobility transistors (HEMTs) are established. The degradation of the electrical properties of the device under the actual radiation environment are analyzed theoretically, and studies of the total dose effects of gamma radiation on AlGaN/AlN/GaN HEMTs at three different radiation bias conditions are carried out. The degradation patterns of the main parameters of the AlGaN/AlN/GaN HEMTs at different doses are then investigated, and the device parameters that were sensitive to the gamma radiation induced damage and the total dose level induced device damage are obtained. (authors)

  3. 60Co gamma radiation effect on AlGaN/AlN/GaN HEMT devices

    Institute of Scientific and Technical Information of China (English)

    WANG Yan-Ping; LUO Yin-Hong; WANG Wei; ZHANG Ke-Ying; GUO Hong-Xia; GUO Xiao-Qiang; WANG Yuan-Ming

    2013-01-01

    The testing techniques and experimental methods of the 60Co gamma irradiation effect on AlGaN/AlN/GaN high electron mobility transistors (HEMTs) are established.The degradation of the electrical properties of the device under the actual radiation environment are analyzed theoretically,and studies of the total dose effects of gamma radiation on AlGaN/AlN/GaN HEMTs at three different radiation bias conditions are carried out.The degradation patterns of the main parameters of the AlGaN/AlN/GaN HEMTs at different doses are then investigated,and the device parameters that were sensitive to the gamma radiation induced damage and the total dose level induced device damage are obtained.

  4. Al-based precipitate evolution during high temperature annealing of Al implanted in Si

    International Nuclear Information System (INIS)

    Al-based precipitate evolution for 80 keV Al ions implanted in Si has been investigated. Precipitates are formed during high temperature annealings of 1 x 1015/cm2 implanted samples. They are located at two depths where Al concentration peaks are detected. Al atoms are gettered into the extended defects present in the crystal and/or precipitate when their concentration is higher than the solid solubility value at the annealing temperature. Increasing annealing time, precipitates dissolve out and only a small fraction of atoms diffuses into the sample, meanwhile the greater part evaporates from the sample. At 1 x 1013/cm2 dose Al concentration is below the solid solubility limit. The secondary defects are not detected and the dopant profile does not display anomalous peaks. Moreover, all the implanted Al is electrically active and remains in the sample during the first instant of annealing. At higher annealing times it diffuses out of the sample reducing the residual dose

  5. Microscopic Properties of Long-Period Ordering in Al-Rich TiAl Alloys

    Science.gov (United States)

    Hata, S.; Nakano, T.; Kuwano, N.; Itakura, M.; Matsumura, S.; Umakoshi, Y.

    2008-07-01

    The ordering mechanism of long-period superstructures (LPSs) in Al-rich TiAl alloys has been investigated by high-resolution transmission electron microscopy (HRTEM). The LPSs are classified in terms of arrangements of base clusters with different shapes and compositions formed in Ti-rich (002) layers of L10-TiAl matrix: square Ti4Al, fat rhombus Ti3Al, and lean rhombus Ti2Al type clusters. The HRTEM observations revealed that antiphase boundaries of long-range-ordered LPS domains and short-range-ordered microdomains are constructed by various space-filling arrangements of the base clusters. Such a microscopic property characterized by the base clusters and their arrangements is markedly analogous to that of the {left< {{text{1,1/2,0}}} rightrangle } * special-point ordering alloys such as Ni-Mo.

  6. Observation of Electronic Shells and Characteristic Products from Mass Abundance Spectra of Al Cluster and Al-C Cluster Anions

    Institute of Scientific and Technical Information of China (English)

    LIU Bing-Chen; ZHAI Hua-Jin; ZHOU Ru-Fang; NI Guo-Quan; XU Zhi-Zhan

    2000-01-01

    Using a laser vaporization/pulsed molecular beam cluster source, Al cluster anions and Al-C mixed cluster anions are produced and recorded by a time of flight mass spectrometer. Mass abundance spectra of the Al cluster anions in the size range from Al2 to Al42 show that Al-13, Al23, Al35, and slightly, Al37 are local maxima, as predicted by the electronic jellium model. Mixed clusters Aln C- and Aln C2 are also shown, among which the most abundant species are Al3 C2 , Al6 C2 , Al7 C- and Al7 C2 in the small size range. The formation mechanism of these products is discussed.

  7. Grain refinement of hypoeutectic Al-Si alloy prepared with ELTA by Al-4B master alloy

    Institute of Scientific and Technical Information of China (English)

    WANG Ming-xing; MENG Xiang-yong; LIU Zhi-yong; LIU Zhong-xia; WENG Yong-gang; SONG Tian-fu; YANG Sheng

    2006-01-01

    Electrolytic low-titanium aluminum (ELTA) was produced by adding TiO2 powder to an industrial aluminum electrolyzer.The grain refining effect of Al-4B master alloy in the hypoeutectic Al-Si alloy prepared by using ELTA was investigated, and compared with those of Al-5Ti, Al-5Ti-1B and Al-4B master alloys in the similar alloy prepared by using pure Al. The results indicate that when Al-4B is added to the melt of the alloy prepared by using ELTA in terms of the Ti/B mass ratio of 5:1, the grain refining effect is better than those of Al-5Ti, Al-5Ti-1B and Al-4B master alloys. Thus, using Al-4B to refine the grain of Al-Si alloys prepared by using ELTA will possibly become a feasible way of obtaining Al-Si alloy with homogeneous and fine microstructure.

  8. In-Situ Synthesis of AlN Powders and Composite AlN Powders with Yttrium Addition

    Institute of Scientific and Technical Information of China (English)

    郑新和; 王群; 林志浪; 李春国; 周美玲

    2002-01-01

    Using Al-Mg and Al-Mg-Y alloys as raw materials and nitrogen as gas reactants, AlN powders and composite AlN powders by in-situ synthesis method were prepared. AlN lumps prepared by the nitriding of Al-Mg and Al-Mg-Y alloys have porous microstructure, which is favorable for pulverization. They have high purity, containing 1.23%(mass fraction) oxygen impurity, and consisted of AlN single phase. The average particle size of AlN powders is 6.78 μm. Composite AlN powders consist of AlN phases and rare earth oxide Y2O3 phase. The distribution of particle size of AlN powders shows two peaks. In view of packing factor, AlN powders with such size distribution can easily be sintered to high density.

  9. Generation and evolution of nanoscale AlP and Al{sub 13}Fe{sub 4} particles in Al-Fe-P system

    Energy Technology Data Exchange (ETDEWEB)

    Qiao, Huan; Gao, Tong; Zhu, Xiangzhen; Wu, Yuying; Qian, Zhao; Liu, Xiangfa, E-mail: xfliu@sdu.edu.cn

    2015-02-15

    Highlights: • Diffusion and gradual solid reactions between Al and Fe{sub x}P phases in Al-Fe-P alloy were investigated. • Nanoscale AlP clusters are in-situ generated and evolve during the whole process. • This novel Al-Fe-P alloy has an excellent low-temperature refining performance on hypereutectic Al-Si alloy. - Abstract: In this paper, the gradual solid reactions between Al and Fe{sub x}P phases in Al-Fe-P alloy were investigated. The results show that the whole reaction process undergoes four main stages: the diffusion of Al atom, the generation of (Al, Fe, P) intermediate compound, the precipitation of nano AlP and Al{sub 13}Fe{sub 4} clusters and their growth to submicron particles. The microstructure of Fe-P particles evolves from the “egg-type”, the “sponge-type” to the “sesame-cake” structure. AlP and Al{sub 13}Fe{sub 4} nano phases have in-situ generated and evolved during the whole process. The gradual reaction mechanism has been discussed. Furthermore, a novel Al-Fe-P alloy which contains (Al, Fe, P) intermediate compounds and nano AlP particles has been synthesized and its low-temperature refining performance on A390 alloy has also been investigated.

  10. TEM characterization of oxidized AlGaAs/AlAs nonlinear optical waveguides

    OpenAIRE

    Guillotel, E; Langlois, C.; Ghiglieno, F.; Leo, G.; Ricolleau, C.

    2010-01-01

    Abstract The internal interfaces of multilayer Al x Ga 1-x As/AlAs nonlinear optical waveguides are investigated by high-angle annular-dark-field and energy-filtered scanning transmission electron microscopy, before and after partial wet oxidation of AlAs layers. Via a simple phenomenological model, the corresponding roughness parameters allow predicting the scattering-induced waveguide optical losses, which are in reasonable agreement with the experimental value of 0.5 cm -1. We also find...

  11. Modified Mechanism of Eutectic Silicon in Al2O3/Al-Si Alloy

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Al2O3/Al-Si alloy composite was manufactured by squeeze casting. The morphology of the eutectic silicon in the composite was observed by scanning electronic microscope (SEM), and the modified mechanism of eutectic silicon in the composite was approached. The alumina fiber in the composite can trigger twin during the growth of Al-Si eutectic and lead to the modification of eutectic silicon near the fiber.

  12. Two-Phase (TiAl+TiCrAl) Coating Alloys for Titanium Aluminides

    Science.gov (United States)

    Brady, Michael P. (Inventor); Smialek, James L. (Inventor); Brindley, William J. (Inventor)

    1998-01-01

    A coating for protecting titanium aluminide alloys, including the TiAl gamma + Ti3Al (alpha(sub 2)) class, from oxidative attack and interstitial embrittlement at temperatures up to at least 1000 C. is disclosed. This protective coating consists essentially of titanium, aluminum. and chromium in the following approximate atomic ratio: Ti(41.5-34.5)Al(49-53)Cr(9.5-12.5)

  13. Effect of the interface in laminated composites of Al-1100 and Al-2024

    International Nuclear Information System (INIS)

    Laminated composites consisting of alternating layers of Al-1100 and Al-2024 were produced by hot rolling, with 45% Al-2024 volume fraction. These composites were subjected to cyclic thermal treatment (various numbers of cycles) and to isothermal treatment (various numbers of cycles) and to isothermal treatment (at peak temperature and for times equivalent to those of the thermal cycles. Microhardness, tensile and fatigue crack arrester modes) were studied in the initial state and after treatments. (E.G.)

  14. Another Security Improvement over the Lin et al.'s E-voting Scheme

    Science.gov (United States)

    Asaar, Maryam Rajabzadeh; Mohajeri, Javad; Salmasizadeh, Mahmoud

    In 2003, Lin et al. have proposed an electronic voting scheme which can be utilized in large-scale elections, and claimed it detects double voting. But in this paper, by presenting an attack, we show that voters can successfully vote more than once without being detected. Hence, we propose a new modified scheme based on the Lin et al.'s scheme with the same efficiency to solve this weakness and analyze its security.

  15. Melt Processing and Characterization of Al-SiC Nanocomposite, Al, and Mg Foam Materials

    OpenAIRE

    Ahmed M. Nabawy; Khalil Abdelrazek Khalil; Al-Ahmari, Abdulrahman M.; Sherif, El-Sayed M.

    2016-01-01

    In the present work, metallic foams of Al, Mg and an Al-SiC nanocomposite (MMNC) have been fabricated using a new manufacturing technique by employing melt infiltration assisted with an electromagnetic force. The aim of this investigation was to study and to develop a reliable manufacturing technique consisting of different types of metallic foams. In this technique, an electromagnetic force was used to assist the infiltration of Al-SiC slurry and of pure liquid metal into a leachable pattern...

  16. Fabrication, phase transformation studies, and characterization of SiC-AlN-Al2OC ceramics

    International Nuclear Information System (INIS)

    Principal focus was on phase transformation, microstructure development, and elevated temperature creep, with some effort on room- temperature mechanical properties of selected materials. Fabrication was largely hot pressing, although many of the compositions can be densified by pressureless sintering; hot pressing was to ensure full attainment of density with fine microstructure. Most of the work was on SiC-AlN and AlN-Al2OC pseudobinaries

  17. Class Schedule Assignment Based on Students Learning Rhythms Using A Genetic Algorithm Asignación de horarios de clase basado en los ritmos de aprendizaje de los estudiantes usando un algoritmo genético

    Directory of Open Access Journals (Sweden)

    Victor F. Suarez Chilma

    2013-03-01

    Full Text Available The objective of this proposal is to implement a school day agenda focused on the learning rhythms of students of elementary and secondary schools using a genetic algorithm. The methodology of this proposal takes into account legal requirements and constraints on the assignment of teachers and classrooms in public educational institutions in Colombia. In addition, this proposal provides a set of constraints focused on cognitive rhythms and subjects are scheduled at the most convenient times according to the area of knowledge. The genetic algorithm evolves through a process of mutation and selection and builds a total solution based on the best solutions for each group. Sixteen groups in a school are tested and the results of class schedule assignments are presented. The quality of the solution obtained through the established approach is validated by comparing the results to the solutions obtained using another algorithm.El objetivo de esta propuesta es implementar un horario escolar que tenga en cuenta los ritmos de aprendizaje en los estudiantes de educación primaria y secundaria, utilizando un algoritmo genético. La metodología considera los requerimientos legales y las restricciones necesarias para la asignación de maestros y aulas en instituciones educativas públicas de Colombia. Adicionalmente, se establecen un conjunto de restricciones relacionadas con el enfoque en los ritmos cognitivos, determinando las horas de la jornada en las que es más conveniente la ubicación de ciertas materias de acuerdo al área del conocimiento al que pertenecen. El algoritmo genético evoluciona mediante un proceso de mutación y selección, a través del cual se construye una solución completa a partir de la búsqueda de las mejores soluciones por grupo. Se presentan los resultados de las pruebas realizadas para la asignación de una institución con 16 grupos. La calidad de las soluciones obtenidas de acuerdo al enfoque establecido es validada

  18. Synthesis of core–shell AlOOH hollow nanospheres by reacting Al nanoparticles with water

    Science.gov (United States)

    Lozhkomoev, A. S.; Glazkova, E. A.; Bakina, O. V.; Lerner, M. I.; Gotman, I.; Gutmanas, E. Y.; Kazantsev, S. O.; Psakhie, S. G.

    2016-05-01

    A novel route for the synthesis of boehmite nanospheres with a hollow core and the shell composed of highly crumpled AlOOH nanosheets by oxidizing Al nanopowder in pure water under mild processing conditions is described. The stepwise events of Al transformation into boehmite are followed by monitoring the pH in the reaction medium. A mechanism of formation of hollow AlOOH nanospheres with a well-defined shape and crystallinity is proposed which includes the hydration of the Al oxide passivation layer, local corrosion of metallic Al accompanied by hydrogen evolution, the rupture of the protective layer, the dissolution of Al from the particle interior and the deposition of AlOOH nanosheets on the outer surface. In contrast to previously reported methods of boehmite nanoparticle synthesis, the proposed method is simple, and environmentally friendly and allows the generation of hydrogen gas as a by-product. Due to their high surface area and high, slit-shaped nanoporosity, the synthesized AlOOH nanostructures hold promise for the development of more effective catalysts, adsorbents, vaccines and drug carriers.

  19. Strain Rates and Grain Growth in Al 5754 and Al 6061 Friction Stir Spot Welds

    Science.gov (United States)

    Gerlich, A.; Yamamoto, M.; North, T. H.

    2007-06-01

    The stir zone temperature and microstructures are compared in friction stir spot welds produced in Al 5754 and Al 6061 alloys. Electron backscattered diffraction was used to determine the relationship between tool rotation speed during welding and final stir zone grain size. Comparison of the grain sizes in rapidly quenched welds with those in air-cooled joints confirmed that grain growth occurred only in Al 6061 spot welds. There was no evidence of abnormal grain growth in the stir zones of Al 6061 welds; the final grain size could be represented using an Arrhenius equation. The strain rates during welding were determined by incorporating the stir zone temperature and average subgrain sizes in quenched spot welds in the Zener-Hollomon relation. When the tool rotation speed increased from 750 to 3000 RPM, the strain rate values ranged from 180 to 497 s-1 in Al 5754 spot welds and from 55 to 395 s-1 in Al 6061 spot welds. It is suggested that a no-slip boundary condition may be appropriate during numerical modeling of Al 5754 and 6061 friction stir spot welding. This is not the case during Al 7075, Al 2024, and Mg-alloy AZ91 spot welding because spontaneous melting facilitates slippage at the tool contact interface.

  20. Study on Mg/Al Weld Seam Based on Zn–Mg–Al Ternary Alloy

    Directory of Open Access Journals (Sweden)

    Liming Liu

    2014-02-01

    Full Text Available Based on the idea of alloying welding seams, a series of Zn–xAl filler metals was calculated and designed for joining Mg/Al dissimilar metals by gas tungsten arc (GTA welding. An infrared thermography system was used to measure the temperature of the welding pool during the welding process to investigate the solidification process. It was found that the mechanical properties of the welded joints were improved with the increasing of the Al content in the Zn–xAl filler metals, and when Zn–30Al was used as the filler metal, the ultimate tensile strength could reach a maximum of 120 MPa. The reason for the average tensile strength of the joint increasing was that the weak zone of the joint using Zn–30Al filler metal was generated primarily by α-Al instead of MgZn2. When Zn–40Al was used as the filler metal, a new transition zone, about 20 μm-wide, appeared in the edge of the fusion zone near the Mg base metal. Due to the transition zones consisting of MgZn2- and Al-based solid solution, the mechanical property of the joints was deteriorated.

  1. Tetragonal phase in Al-rich region of U-Fe-Al system

    Energy Technology Data Exchange (ETDEWEB)

    Meshi, L. [Department of Materials Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Zenou, V. [Nuclear Research Center-Negev, P.O. Box 9001, Beer-Sheva (Israel); Ezersky, V. [Department of Materials Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel); Munitz, A. [Nuclear Research Center-Negev, P.O. Box 9001, Beer-Sheva (Israel); Talianker, M. [Department of Materials Engineering, Ben-Gurion University of the Negev, Beer-Sheva 84105 (Israel)]. E-mail: mital@bgumail.bgu.ac.il

    2005-10-27

    A new ternary aluminide U{sub 2}FeAl{sub 20} with the approximate composition Al-4.2at% Fe-8.5at% U was observed in the Al-rich corner of the U-Al-Fe system. Transmission electron microscopy and electron microdiffraction technique were used for characterization of the structure of this phase. It has a tetragonal unit cell with the parameters a=12.4A and c=10.3A and can be described by the space group I4-bar 2m.

  2. Tetragonal phase in Al-rich region of U-Fe-Al system

    International Nuclear Information System (INIS)

    A new ternary aluminide U2FeAl20 with the approximate composition Al-4.2at% Fe-8.5at% U was observed in the Al-rich corner of the U-Al-Fe system. Transmission electron microscopy and electron microdiffraction technique were used for characterization of the structure of this phase. It has a tetragonal unit cell with the parameters a=12.4A and c=10.3A and can be described by the space group I4-bar 2m

  3. AlN/IDT/AlN/Sapphire SAW Heterostructure for High-Temperature Applications.

    Science.gov (United States)

    Legrani, Ouarda; Aubert, Thierry; Elmazria, Omar; Bartasyte, Ausrine; Nicolay, Pascal; Talbi, Abdelkrim; Boulet, Pascal; Ghanbaja, Jaafar; Mangin, Denis

    2016-06-01

    Recent studies have evidenced that Pt/AlN/Sapphire surface acoustic wave (SAW) devices are promising for high-temperature high-frequency applications. However, they cannot be used above 700°C in air atmosphere as the Pt interdigital transducers (IDTs) agglomerate and the AlN layer oxidizes in such conditions. In this paper, we explore the possibility to use an AlN protective overlayer to concurrently hinder these phenomena. To do so, AlN/IDT/AlN/Sapphire heterostructures undergo successive annealing steps from 800°C to 1000°C in air atmosphere. The impact of each step on the morphology, microstructure, and phase composition of AlN and Pt films is evaluated using optical microscopy, scanning and transmission electron microscopy (SEM and TEM), X-ray diffraction (XRD), and secondary ion mass spectroscopy (SIMS). Finally, acoustical performance at room temperature of both protected and unprotected SAW devices are compared, as well as the effects of annealing on these performance. These investigations show that the use of an overlayer is one possible solution to strongly hinder the Pt IDTs agglomeration up to 1000°C. Moreover, AlN/IDT/AlN/Sapphire SAW heterostructures show promising performances in terms of stability up to 800°C. At higher temperatures, the oxidation of AlN is more intense and makes it inappropriate to be used as a protective layer. PMID:27076407

  4. Sintering Behavior of CNT Reinforced Al6061 and Al2124 Nanocomposites

    OpenAIRE

    2014-01-01

    Ball milling and spark plasma sintering were successfully used to produce carbon nanotube reinforced Al6061 and Al2124 nanocomposites which have potential applications in the fields of aerospace, automotive, electronics, and high precision instrumentation. Al2124 and Al6061 nanocomposite powders containing 0.5 to 2 wt.% CNTs prepared through sonication and wet ball milling were spark plasma sintered at 400, 450, and 500°C for 20 minutes under a pressure of 35 MPa. CNTs were better dispersed, ...

  5. Microstructure and mechanical properties of Al2O3/TiAl composite

    Institute of Scientific and Technical Information of China (English)

    AI Tao-tao; WANG Fen; ZHU Jian-feng

    2006-01-01

    Al2O3/TiAl composites were fabricated by PAXD (pressure-assisted exothermic dispersion) method. The effects of Nb2O5 content on the microstructure and mechanical properties of the composites were investigated. The results show that the ultimate phases of the composite consist of TiAl, Ti3Al, Al2O3 and a small amount of NbAl3. SEM reveals that a submicron γ+(α2/γ) dual phases structure can be presented after sintered at 1 200 ℃. Furthermore, with the increase of Nb2O5 content, the ratio of TiAl to Ti3Al phase decreases correspondingly, the grains of the composites are remarkably refined, and the produced Al2O3 particles are uniformly dispersed. When 6% Nb2O5 is added, the composite has the best comprehensive properties. It exhibits a Vickers hardness of 4.77 GPa and a bending strength of 642 MPa. Grain-refinement and dispersion-strengthening are the main strengthening mechanisms.

  6. Production of AlN-Si-Al Ceramic-Metal Composites via Pressurless Infiltration Method

    OpenAIRE

    KALEMTAŞ, Ayşe; ARSLAN, Gürsoy; KARA, Ferhat

    2014-01-01

    In this work, the production of light (∼2,9 g/cm3) and dense (> 99 %) AlN based ceramic metal composites was conducted by the pressureless melt infiltration method. These composites contain a high ceramic volume fraction (> 50 vol %) which is the result of the reaction between Si3N4 and Al in the Si3N4-Al system. The production of the ceramic-metal composites was achieved via infiltrating 2024 Al alloys at different temperatures and holding times into the porous pellets which were prepared us...

  7. Coating of a layer of Au on Al13 : The findings of icosahedral Al@Al12Au20- and Al12Au202- fullerenes using ab initio pseudopotential calculations

    Science.gov (United States)

    Kumar, Vijay

    2009-02-01

    We report results of ab initio pseudopotential calculations on the nanocoating of gold on an icosahedral Al13 cluster and the findings of icosahedrally symmetric endohedral Al@Al12Au20- and empty cage Al12Au202- compound fullerenes formed of metal atoms. Twelve Al atoms cap the pentagonal faces of a dodecahedral Au20 cage in which each Au atom has three Al atoms and three Au atoms as nearest neighbors. Mixing of Al13 and Au20 magic clusters leads to a large heat of formation of 0.55 eV/atom and high stability of the Al@Al12Au20 compound fullerene. The binding energies of Al12Au20 and Al@Al12Au20 are 3.017 and 3.007 eV/atom, respectively, which are much larger than 2.457 eV/atom for Au32 fullerene, leading to the possibility of their high abundance.

  8. Deletion of ALS5, ALS6 or ALS7 increases adhesion of Candida albicans to human vascular endothelial and buccal epithelial cells

    OpenAIRE

    Zhao, Xiaomin; Oh, Soon-Hwan; Hoyer, Lois L.

    2007-01-01

    C. albicans yeast forms deleted for ALS5, ALS6 or ALS7 are more adherent than a relevant control strain to human vascular endothelial cell monolayers and buccal epithelial cells. In the buccal and vaginal reconstituted human epithelium (RHE) disease models, however, mutant and control strains caused a similar degree of tissue destruction. Deletion of ALS5 or ALS6 significantly slowed growth of the mutant strain; this phenotype was not affected by addition of excess uridine to the culture medi...

  9. Análisis de órbitas experimentales del LHC usando el método de salto de acción y fase / Analysis of the LHC experimental orbits using the action and phase method

    OpenAIRE

    Blanco García, Oscar Roberto

    2012-01-01

    En este trabajo se mencionan diferentes técnicas para la corrección del órbitas en aceleradores de partículas, y se desarrolla el método de salto de acción y fase, que fue revisado y analizado para su aplicación en el Gran Colisionador de Hadrones (LHC, Large Hadron Collider). Al ser aplicado, se obtuvieron valores representativos para la región de interacción 3. Se estableció el límite para la precisión del método en ±0.01% en condiciones ideales y ±1.56% en condiciones donde los datos ti...

  10. Estudio del equilibrio y cinética de adsorción de Cd(II), Ni(II) y Cr(VI) usando Quitosano y Quitosano modificado con cobre

    OpenAIRE

    Benavente, M.; Castro, S; N. Betanco; F. Canelo; López, X. (Xosé); García, A.

    2013-01-01

    En este trabajo, se estudió el equilibrio y la cinética de adsorción de Cd(II), Ni(II) en quitosano y Cr(VI) en quitosano modificado con cobre. Para ello, soluciones de iones metálicos a diferentes concentraciones, fueron puestas en contacto con el adsorbente y se agitaron por un período de 3 – 4 h. Al final del proceso, las muestras fueron analizadas en un espectrómetro de absorción atómica. Los datos experimentales del equilibrio de adsorción de los iones metálicos fueron evaluados aplicand...

  11. Melting Transition of Small Aluminium Clusters Al11-20

    Institute of Scientific and Technical Information of China (English)

    ZHANG Wei; ZHANG Feng-Shou; ZHU Zhi-Yuan

    2007-01-01

    Heat capacities of small aluminium clusters Al11-20 are investigated using MD simulation with empirical manybody Gupta potential. The heat capacities of some clusters Al11, Al12, Al13 and Al19 show well-defined peaks while the heat capacities of Al15-18 indicate a gradual melting transition. The spectra of isomers obtained by quenches along the MD trajectory give good interpretation for those results.

  12. Kerja Perspektif Al-Qur'an

    Directory of Open Access Journals (Sweden)

    Ahmad Munir

    2011-05-01

    Full Text Available The moslem ethics of life is based on movement as ex­pressed in certain terms like al-sharī’ah, al-tarīqah, al-sirāt, al-sabīl and al-manhaj, that make sense of way and teachings to achieve good life. Islam obliges and gives appreciation of the achievements of Mus­lims. The Qur’an uses several terms to refer to such work; ‘charity, kasb, juhd, ibtighâ’, sa ’yu and su ’âl. From this concept, the Qur’an considers work as nob­le, while begging is despicable. Work means thankful to God for the potential He bestows. The Qur’an promotes work not only because it is the way to achieve the wealth, but also because it possesses the its sacred value for the benefit of fulfilling livelihood. Therefore the work should also be done based on ethical values .

  13. 26Al in the interstellar medium

    International Nuclear Information System (INIS)

    Several different lines of physical reasoning have converged on the importance of the radioactive nucleus 26Al. The sciences of meteoritics, nucleosynthesis, gamma-ray astronomy, galactic chemical evolution, solar system formation, and interstellar chemistry all place this nucleus in a central position with possible profound implications. Perhaps more importantly the study of this radioactivity can unite these diverse fields in a complicated framework which will benefit all of them. This review traces the evolution of ideas concerning 26Al in the context of these disciplines. 26Al was first discussed for the possibility that its decay energy could melt meteorite parent bodies, and its daughter, 26Mg, was later found in meteorites with enhanced abundance. It was also among the first radioactivities expected to be synthesized in interestingly large quantities in nulceosynthetic events. The first definitive detection of gamma-rays from an interstellar radioactivity is that of 1.809 MeV gamma-rays from 26Al. This discovery has many implications, some of which are outlined here. The whole problem of isotopic anomalies in meteorites is greatly influenced by the specific issues surrounding excess 26Mg, whether it represents in situ decay of 26Al or memory of conditions of the ISM. The relationships among these ideas and their implications are examined. (orig.)

  14. Cd ion implantation in AlN

    International Nuclear Information System (INIS)

    Highlights: ► Cd ion implanted in AlN thin films. ► XRD shows damage produced during implantation. ► Annealing recovers damage in low fluence sample. ► RBS/C measurements show that Cd occupies substitutional sites. ► Cd can be a good candidate for p-type doping. - Abstract: AlN thin films were implanted with cadmium, to fluences of 1 × 1013 and 8 × 1014 at/cm2. The implanted samples were annealed at 950 °C under flowing nitrogen. Although implantation damage in AlN is known to be extremely stable the crystal could be fully recovered at low fluences. At high fluences the implantation damage was only partially removed. Implantation defects cause an expansion of the c-lattice parameter. For the high fluence sample the lattice site location of the ions was studied by Rutherford Backscattering/Channelling Spectrometry. Cd ions are found to be incorporated in substitutional Al sites in the crystal and no significant diffusion is seen upon thermal annealing. The observed high solubility limit and site stability are prerequisite for using Cd as p-type dopant in AlN.

  15. Survey and alignment at the ALS

    International Nuclear Information System (INIS)

    This paper describes survey and alignment at the Lawrence Berkeley National Laboratory's Advanced Light Source (ALS) accelerators from 1993 to 1995. The ALS is a 1.0 - 1.9 GeV electron accelerator producing extremely bright synchrotron light in the UV and soft-X-ray wavelengths. At the ALS, electrons are accelerated in a LINAC to 50 MeV, injected into a booster ring for further acceleration and finally injected into the storage ring. This is shown schematically in Figure 1. The storage ring, some 200 m in circumference, has been run with electron currents above 400 mA with lifetimes as high as 24 hours. The ALS is a third generation light source and requires for efficient storage ring operation, magnets aligned to within 150 mm of their ideal position. To accomplish this a network of monuments was established and their positions measured with respect to one another. The data was reduced using GEONET'' and STAR*NET'' software. Using the monuments as reference points, magnet positions were measured and alignment confirmed using the Kem Electronic Coordinate Determination System (ECDS''). A number of other papers dealing with survey and alignment (S ampersand A) at the ALS have been written that may further elucidate some details of the methods and systems described in this paper

  16. Direct laser cooling Al+ ions optical clocks

    CERN Document Server

    Zhang, J; Luo, J; Lu, Z H

    2016-01-01

    Al$^+$ ions optical clock is a very promising optical frequency standard candidate due to its extremely small blackbody radiation shift. It has been successfully demonstrated with indirect cooled, quantum-logic-based spectroscopy technique. Its accuracy is limited by second-order Doppler shift, and its stability is limited by the number of ions that can be probed in quantum logic processing. We propose a direct laser cooling scheme of Al$^+$ ions optical clocks where both the stability and accuracy of the clocks are greatly improved. In the proposed scheme, two Al$^+$ ions traps are utilized. The first trap is used to trap a large number of Al$^+$ ions to improve the stability of the clock laser, while the second trap is used to trap a single Al$^+$ ions to provide the ultimate accuracy. Both traps are cooled with a continuous wave 167 nm laser. The expected clock laser stability can reach $9.0\\times10^{-17}/\\sqrt{\\tau}$. For the second trap, in addition to 167 nm laser Doppler cooling, a second stage pulsed ...

  17. Epistemologi Penafsiran Ilmiah al-Qur’an

    Directory of Open Access Journals (Sweden)

    Sujiat Zubaidi Saleh

    2011-04-01

    Full Text Available The main objective in interpretating al-Qur’an is to explain the will of God and the operationalization of the will in the field of faith, laws, or ethics. At the phase of Islamic civilization, when the linguistic and philosophy science codified, raises the various method (manhaj, and interpretation streams (ittijahat, exegesis school (madzhab of al-Qur’an. In addition, also found in various shades of interpretation such as: fiqhi, kalami, balaghi, and isyari/ sufi, even philosophical. It was also discovered methods of tafsir ‘ilmi oriented to the utilization of the discovering science in order to prove the truth of scientific fact. The last pattern was ignited pro and contra among scholars and mufassir. As we know that alQur’an was not descended in the condition of cultural vacuum but it is a form of dialectics and the response to the condition and social situation, politic, and religion. This is relevant to the characteristics of al-Qur’an which can be applied throughout the periods. As we understood that interpretation is one of reflections of thought and civilization products. It always developed and influenced by the dynamics of human civilization, so in its development, science and al-Qur’an can be brought together in dialogue, although with some prerequisites specified interpretation.

  18. MOSQUE ARCHITECTURE AS A SUSTAINABLE BUILDING IN URBAN (Case Study: Al Markas Al Islamic Mosque Makassar

    Directory of Open Access Journals (Sweden)

    Imriyanti Imriyanti

    2014-02-01

    Full Text Available Abstract Mosque Architecture is a part of Islamic architecture. Mosque should be fused with elements of nature because its function as a place to pray to God who created the universe. Al Markas Al Islamic Makassar mosque is used as a center of Islamic aspirations of the people and the government to accommodate all the activities of moslems in Makassar. Through this function, the provision of Al Markas Al Islamic mosque began from the desire of Islamic societies in Makassar, which wants the Islamic center to be equipped with facilities and infrastructure as well as architectural, monumental buildings and structures that can be last for hundreds of years (continuous, blend with the environment, and also can be used by the public. Having regard to the function of a mosque especially at the Al Markas Al Islamic Makassar mosque, then the problem that arise is how the Al Markas Al Islamic mosque can be survived/sustainable  in order  to function  as a place  of worship  and  as a center  of Islam.  This research  is a descriptive qualitative research that is trying to generate data in the form of systematic and accurate picture of the object of study. The sustaiprophetlity  of Al Markas AL Islamic mosque can be known through the concept of Islam  in accordance with the view of Islam as well as the sustaiprophetlity of the buildings that seen in the spatial pattern of the mosque, appearance, natural lighting, natural ventilation, and user behavior of the mosque. Keywords: mosque architecture, sustaiprophetlity, view of Islam     Abstrak Arsitektur masjid merupakan bagian dari arsitektur Islam. Bangunan masjid sebaiknya dapat menyatu dengan unsur alam karena masjid difungsikan sebagai wadah dalam bersujud/sembahyang  kepada Allah SWT yang menciptakan alam semesta ini. Masjid Al Markas Al Islamic Makassar merupakan kompleks kegiatan Islam yang digunakan sebagai pusat aspirasi masyarakat  dan pemerintahan  yang dapat menampung

  19. Percutaneous vertebroplasty: a comparison between the procedure using the traditional and the new side-opening cannula for osteoporotic vertebral fracture Vertebroplastia percutânea: uma comparação entre o procedimento usando a cânula tradicional e a nova cânula de orifício lateral para fratura vertebral osteoporótica

    Directory of Open Access Journals (Sweden)

    Nicandro Figueiredo

    2009-06-01

    Full Text Available A total of 47 percutaneous vertebroplasties (PVs were performed for osteoporotic vertebral fractures in 31 patients, 25 PVs were performed using the frontal-opening cannula (FOC and 22 using the new side-opening cannula (SOC, randomly distributed. The incidence of cement extrusion was 27% with the SOC, and 68% with the FOC, all asymptomatic (pUm total de 47 vertebroplastias percutâneas (VP foram realizadas para fraturas vertebrais osteoporóticas em 31 pacientes, 25 VP foram realizadas usando-se a cânula de orifício frontal (COF e 22 com a nova cânula de orifício lateral (COL, distribuídos randomicamente. A incidência de extrusão de cimento ortopédico ocorreu em 27% com a COL, e 68% com a COF, todas assintomáticas (p<0,01. O controle da dor foi similar em ambos os grupos, com boa melhora da dor na maioria dos pacientes, sem complicações clínicas relevantes. A extrusão do cimento pode ser significativamente reduzida com esta nova COL, que permite uma melhor injeção do cimento para o centro do corpo vertebral, aumentando a segurança do procedimento, sem aumento no seu custo.

  20. Reducciones temporales para convertir la sintaxis abstracta del diagrama de flujo de tareas no estructurado al álgebra de tareas

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Fernández-y-Fernández

    2015-12-01

    Full Text Available Este artículo describe nuestro trabajo en el modelado de software usando reducciones temporales para representar diagramas de flujo no estructurado, como una representación intermedia para construir una expresión textual en una álgebra de procesos particular. Este trabajo fue realizado para poder construir una herramienta CASE de apoyo para la fase del modelado de tareas en el Método Discovery para el desarrollo de software. Inicialmente explicaremos las similitudes entre dos tipos de diagramas, el diagrama de actividades de UML y el diagrama de flujo de tareas con su representación formal (el álgebra de tareas. Posteriormente, ofreceremos una explicación explicando la generación automática, usando las reducciones temporales, de expresiones en el álgebra de tareas usando información abstracta que es obtenida de los diagramas de flujo de tareas.

  1. Instability of TiC and TiAl3 compounds in Al-10Mg and Al-5Cu alloys by addition of Al-Ti-C master alloy

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The performance of Al-Ti-C master alloy in refining Al-10Mg and A1-5Cu alloys was studied by using electron probe micro-analyzer (EPMA) and X-ray diffractometer (XRD) analysis.The results indicate that there are obvious fading phenomena in both Al-10Mg and Al-5Cu alloys with the addition of Al-5Ti-0.4C refiner which contains TiC and TiAl3 compounds.Mg element has no influence on the stability of TiC and TiAl3, while TiC particles in Al-10Mg alloy react with Al to form Al4C3 particles, resulting in the refinement fading.However, TiC particles are relatively stable in Al-5Cu alloy, while TiAl3 phase reacts with Al2Cu to produce a new phase Ti(Al, Cu)2, which is responsible for the refinement fading in Al-5Cu alloy.These indicate that the refinement fading will not occur only when both the TiC particles and TiAl3 compound of Al-Ti-C refiner are stable in Al alloys.

  2. Study of corrosion inhibition of coupled Al2Cu–Al and Al3Fe–Al by cerium cinnamate using scanning vibrating electrode technique and scanning ion-selective electrode technique

    International Nuclear Information System (INIS)

    Highlights: • The corrosion inhibition of coupled Al2Cu–Al and Al3Fe–Al by cerium cinnamate was studied. • SVET and SIET were used to study the distribution of current densities and pH. • The corrosion inhibition mechanisms were analyzed. - Abstract: The galvanic corrosion of the coupled Al2Cu and Al as well as Al3Fe and Al in 0.005 M NaCl in and without the presence of cerium cinnamate was studied. Scanning vibrating electrode technique and scanning ion-selective electrode technique were used to measure the distribution of current densities and pH. The results indicate that cerium cinnamate played inhibiting effect on the coupling corrosion of Al2Cu–Al and Al3Fe–Al. For Al2Cu–Al, the inhibition was mainly influenced by the production of cerium oxide/hydroxide on Al2Cu surface. However, for Al3Fe–Al, the inhibition was mainly influenced by the adsorbed cerium cinnamate on the Al3Fe surface

  3. MgAl2O4–-Al2O3 solid solution interaction: mathematical framework and phase separation of -Al2O3 at high temperature

    Indian Academy of Sciences (India)

    Soumen Pal; A K Bandyopadhyay; S Mukherjee; B N Samaddar; P G Pal

    2011-07-01

    Although existence of MgAl2O4–-Al2O3 solid solution has been reported in the past, the detailed interactions have not been explored completely. For the first time, we report here a mathematical framework for the detailed solid solution interactions of -Al2O3 in MgAl2O4 (spinel). To investigate the solid solubility of -Al2O3 in MgAl2O4, Mg–Al spinel (MgO–Al2O3; = 1, 1.5, 3, 4.5 and an arbitrary high value 30) precursors have been heat treated at 1000°C. Presence of only non-stoichiometric MgAl2O4 phase up to = 4.5 at 1000°C indicates that alumina (as -Al2O3) present beyond stoichiometry gets completely accommodated in MgAl2O4 in the form of solid solution. → alumina phase transformation and its subsequent separation from MgAl2O4 has been observed in the Mg–Al spinel powders ( > 1) when the 1000°C heat treated materials are calcined at 1200°C. In the mathematical framework, unit cell of MgAl2O4 (Mg8Al16O32) has been considered for the solid solution interactions (substitution of Mg2+ ions by Al3+ ions) with -Al2O3. It is suggested that combination of unit cells of MgAl2O4 takes part in the interactions when > 5 (MgO–Al2O3).

  4. Al- Khwarizmi and axiomatic foundation of algebra

    International Nuclear Information System (INIS)

    This paper intends to investigate the axiomatic foundations of algebra, as they were presented in the book of algebra of al-Khwarizmi (9 th century), and as they were developed in many subsequent Arabic works. The paper gives also a description of algebra evolution towards a discipline independent ofgeometry and arithmetic: the two disciplines whosemarriage had led to its birth.By an in depth reading of some details in the text of al Khwarizmi , we concluded that this mathematician intended to lay down the axiomatic foundations of that new discipline. His resort to arithmetical and geometrical means was a way of making his theory more accessible. He used them to justify the axioms: those that were not explicitly introduced per se, and those that were remained implicit. The paper also relies on some unedited writingsof al-Khwarizmi's successors, which could shedlight on the ways they used to consolidate the foundations of algebra and improve its methods. (author)

  5. Moessbauer studies on Al-Co ferrites

    International Nuclear Information System (INIS)

    Moessbauer spectroscopy studies have been performed on the spinel CoAlxFe2-xO4 (.2≤x≤1.7) in the temperature range 77-750 K using either a liquid nitrogen bath cryostat or a furnace. The samples are magnetic at 77 K giving spectra that have magnetic sextets coexisting with a central line which increases in population with the Al-content indicating relaxation effects. The data shows that Al possesses no preference to either tetrahedral or octahedral sites of the ferrite over the whole range of concentration. The Moessbauer hyperfine interaction parameters and magnetic transition temperatures were determined. As expected the hyperfine field and Curie temperature decrease when the Al-content increases. (orig.)

  6. Magnetic Properties of NdAl2

    DEFF Research Database (Denmark)

    Bak, P.

    1974-01-01

    The magnetic properties of NdAl2 are calculated using a Hamiltonian including crystal-field and isotropic exchange interaction terms. A two-dimensional mean-field theory is evaluated to calculate single-crystal magnetization curves. It is shown that the magnetic properties can be understood using...... the crystal-field parameters derived from the magnetic exciton spectrum measured by Houmann et al. by means of inelastic neutron scattering. The combined lambda -Schottky anomaly in the heat capacity is explained. No additional parameters are introduced.......The magnetic properties of NdAl2 are calculated using a Hamiltonian including crystal-field and isotropic exchange interaction terms. A two-dimensional mean-field theory is evaluated to calculate single-crystal magnetization curves. It is shown that the magnetic properties can be understood using...

  7. Autologous Stem Cell Transplant for AL Amyloidosis

    Directory of Open Access Journals (Sweden)

    Vivek Roy

    2012-01-01

    Full Text Available AL amyloidosis is caused by clonal plasma cells that produce immunoglobulin light chains which misfold and get deposited as amyloid fibrils. Therapy directed against the plasma cell clone leads to clinical benefit. Melphalan and corticosteroids have been the mainstay of treatment for a number of years and the recent availability of other effective agents (IMiDs and proteasome inhibitors has increased treatment options. Autologous stem cell transplant (ASCT has been used in the treatment of AL amyloidosis for many years. It is associated with high rates of hematologic response and improvement in organ function. However, transplant carries considerable risks. Careful patient selection is important to minimize transplant related morbidity and mortality and ensure optimal patient outcomes. As newer more affective therapies become available the role and timing of ASCT in the overall treatment strategy of AL amyloidosis will need to be continually reassessed.

  8. Thermal Properties of Al-50%Si Alloys

    Institute of Scientific and Technical Information of China (English)

    Akio Nishimoto; Katsuya Akamatsu; Kazuyoshi Nakao; Kazuo Ichii

    2004-01-01

    In order to prepare a hypereutectic Al-Si alloy with low coefficients of thermal expansion (CTE), Al-50was produced by powder metallurgy (P/M) and ingot metallurgy (I/M). P/M specimen was prepared by mechanical alloying(MA) and pulsed electric-current sintering (PECS). The microstructures of specimens were characterized by optical microscopy and scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectroscopy (EDS). Vickers microhardness and CTE measurements were performed. The grains in the P/M specimen were refined with increasing MA time. Primary Si and eutectic Si in the I/M specimen were remarkably refined by adding minute amounts of Sr. The CTE of P/M and I/M specimens were estimated as 7.8×10-6 and 10.7×10-6, respectively. These values were as same as a CTE of Al2O3 ceramics.

  9. Kritik Terhadap Pemikiran Tasawuf Al-Raniri

    Directory of Open Access Journals (Sweden)

    Syaifan Nur

    2013-12-01

    Full Text Available Abstract : Al-Raniri is often positioned by some scholars as “superior” figure, which is contrasted to Hamzah Fansuri and Syamsuddin Sumaterani, and that is why they predicate him as one of pioneer of Islamic reformer in Malay- Indonesian archipelago. Anti-wujūdiyyah Sufism campaign by al-Raniri quite successful to some extent to amputate the rate of development of philosophical Sufism was brought by Fansuri and Sumaterani in the one hand, and strike off the nature of moral Sufism in the other, redeemed by bloodshed. This article discussed the “superiority” of al-Raniri’s thought of Sufism, viewed from a broader spectrum, either in relation to problems of faith or theology and politics surrounding the circumstance of his time.Keywords : Philosophical tasawuf, neo-sufism, panteism, tajalli, God’s attributeAbstrak : Al-Raniri oleh banyak kalangan seringkali diposisikan sebagai tokoh “superior” yang diperlawankan dengan Hamzah Fansuri dan Syamsuddin Sumaterani, dan itu sebabnya para ahli memberinya predikat sebagai seorang pelopor pembaru (mujaddid Islam di Nusantara. Anti tasawuf wujūdiyyah yang dikampanyekan oleh al-Raniri cukup berhasil mengamputasi laju perkembangan tasawuf falsafi yang dibawa oleh Fansuri dan Sumaterani di satu sisi, dan melancarkan laju corak tasawuf akhlaki di sisi lain, yang ditebus dengan cara pertumpahan darah. Tulisan ini mendiskusikan “superioritas” pemikiran tasawuf al-Raniri tersebut, dilihat dari spektrum yang lebih luas, baik menyangkut persoalan keyakinan atau teologi maupun politik yang mengitari situasi zamannya.Kata kunci : Tasawuf falsafi , neo-sufisme, panteisme, tajalli, sifat Tuhan

  10. Fabrication of Al-Al3Ti/Ti3Al Functionally Graded Materials under a Centrifugal Force

    Directory of Open Access Journals (Sweden)

    Yoshimi Watanabe

    2010-09-01

    Full Text Available Fabrication of Al-Al3Ti functionally graded materials (FGMs under the centrifugal force has recently attracted some attention. The controlled compositional gradient of the fabricated FGMs, the low cost of the process, and the good mold filling, are the main advantages of the centrifugal method (CM. Using the conventional CM techniques such as the centrifugal solid-particle method and centrifugal in-situ method, FGMs rings with gradually distributed properties could be achieved. As a more practical choice, the centrifugal mixed-powder method (CMPM was recently proposed to obtain FGMs containing nano-particles selectively dispersed in the outer surface of the fabricated parts. However, if a control of the particles morphology, compound formulas or sizes, is desired, another CM technique is favored. As a development of CMPM, our novel reaction centrifugal mixed-powder method (RCMPM has been presented. Using RCMPM, Al‑Al3Ti/Ti3Al FGMs with good surface properties and temperature controlled compositional gradient could be achieved. In this short review, this novel method will be discussed in detail and the effect of RCMPM processing temperature on the reinforcement particles morphology, size and distribution through the fabricated samples, will be reviewed.

  11. Total energy, equation of state and bulk modulus of AlP, AlAs and AlSb semiconductors

    Indian Academy of Sciences (India)

    A R Jivani; H J Trivedi; P J Gajjar; A R Jani

    2005-01-01

    Recently proposed model potential which combines both linear and quadratic types of interactions is employed for the investigation of some properties like the total energy, equation of state and bulk modulus of AlP, AlAs and AlSb semiconductor compounds using higher-order perturbation theory. The model potential parameter is determined using zero pressure condition. The ratio of the covalent bonding term E cov to the second-order term 2 is 6.77% to 11.85% which shows that contribution from higher order terms are important for zinc-blende-type crystals. The calculated numerical results of the total energy, energy band gap at Jones-zone face and bulk modulus of these compounds are in good agreement with the experimental data and found much better than other such theoretical findings. We have also studied pressure–volume relations of these compounds. The present study is carried out using six different screening functions along with latest screening function proposed by Sarkar et al. It is found from the present study that effect of exchange and correlation is clearly distinguishable.

  12. Diffusion AlSi-MeCrAlY coatings obtained on intermetallic γ-TiAl phase

    Directory of Open Access Journals (Sweden)

    M. Góral

    2012-12-01

    Full Text Available Purpose: The development of new protective coatings for TiAl intermetallics was conducted. The MeCrAlYAlSi slurry was used with different amount of aluminium-silicon powder in the binder.Design/methodology/approach: The slurry consisting of aluminium and silicon powder with the addition of MeCrAlY powder were used during the procedure. The inorganic solution made from chromic and phosphoric acid was applied as a binder. The preliminary research of microstructure of obtained coatings was conducted.Findings: The obtained coating consisting of 3 or 4 zones (depending on chemical composition of the slurry was obtained during the annealing process (950°C/4h.Research limitations/implications: The research results revealed the possibility of obtaining coatings with complex phase and chemical composition.Practical implications: Many problems connected with sedimentation of heavier MeCrAlY powder were observed.Originality/value: The copletele new technologies was described in article

  13. Melting, Processing, and Properties of Disordered Fe-Al and Fe-Al-C Based Alloys

    Science.gov (United States)

    Satya Prasad, V. V.; Khaple, Shivkumar; Baligidad, R. G.

    2014-09-01

    This article presents a part of the research work conducted in our laboratory to develop lightweight steels based on Fe-Al alloys containing 7 wt.% and 9 wt.% aluminum for construction of advanced lightweight ground transportation systems, such as automotive vehicles and heavy-haul truck, and for civil engineering construction, such as bridges, tunnels, and buildings. The melting and casting of sound, porosity-free ingots of Fe-Al-based alloys was accomplished by a newly developed cost-effective technique. The technique consists of using a special flux cover and proprietary charging schedule during air induction melting. These alloys were also produced using a vacuum induction melting (VIM) process for comparison purposes. The effect of aluminum (7 wt.% and 9 wt.%) on melting, processing, and properties of disordered solid solution Fe-Al alloys has been studied in detail. Fe-7 wt.% Al alloy could be produced using air induction melting with a flux cover with the properties comparable to the alloy produced through the VIM route. This material could be further processed through hot and cold working to produce sheets and thin foils. The cold-rolled and annealed sheet exhibited excellent room-temperature ductility. The role of carbon in Fe-7 wt.% Al alloys has also been examined. The results indicate that Fe-Al and Fe-Al-C alloys containing about 7 wt.% Al are potential lightweight steels.

  14. Adhesion of metal carbide/nitride interfaces: Al/TiC and Al/TiN

    Science.gov (United States)

    Liu, L. M.; Wang, S. Q.; Ye, H. Q.

    2003-12-01

    We employ density functional theory to investigate and compare Al/TiC and Al/TiN interfaces by electronic structures, relaxed atomic geometries and adhesions. The results show that the preferred bonding site is the interfacial Al atoms above the ceramic's metalloid atoms for both systems. The calculated adhesion energies are quantitatively in agreement with other calculated and experimental results of Al on the carbide and nitride. A detailed comparison of the adhesion energies and relaxed structures shows weaker bonding and less relaxation in the Al/nitride case, which is correlated with the lower surface energy of the ceramic. We have thoroughly characterized the electronic structure and determined that the polar covalent Al3sp-C(N)2s bonds constitute the primary interfacial bonding interaction. The larger overlapping bonding states at the Al/TiC interface reveal the reason why it exhibits relatively larger adhesion energy. Cleavage may take place preferentially at the interface, especially for the Al/TiN, which is in agreement with experimental results.

  15. Adhesion of metal-carbide/nitride interfaces: Al/TiC and Al/TiN

    International Nuclear Information System (INIS)

    We employ density functional theory to investigate and compare Al/TiC and Al/TiN interfaces by electronic structures, relaxed atomic geometries and adhesions. The results show that the preferred bonding site is the interfacial Al atoms above the ceramic's metalloid atoms for both systems. The calculated adhesion energies are quantitatively in agreement with other calculated and experimental results of Al on the carbide and nitride. A detailed comparison of the adhesion energies and relaxed structures shows weaker bonding and less relaxation in the Al/nitride case, which is correlated with the lower surface energy of the ceramic. We have thoroughly characterized the electronic structure and determined that the polar covalent Al3sp-C(N)2s bonds constitute the primary interfacial bonding interaction. The larger overlapping bonding states at the Al/TiC interface reveal the reason why it exhibits relatively larger adhesion energy. Cleavage may take place preferentially at the interface, especially for the Al/TiN, which is in agreement with experimental results

  16. InAlGaAs/AlGaAs quantum wells: line widths, transition energies and segregation

    DEFF Research Database (Denmark)

    Jensen, Jacob Riis; Hvam, Jørn Märcher; Langbein, Wolfgang

    2000-01-01

    We investigate the optical properties of InAlCaAs/AlGaAs quantum wells pseudomorphically grown on GaAs using molecular beam epitaxy (MBE). The transition energies, measured with photoluminescence (PL), are modelled solving the Schrodinger equation, and taking into account segregation in the group...

  17. Introducción al derecho

    OpenAIRE

    Collado Luis, Santiago

    2012-01-01

    Manual de la asignatura introducción al derecho. Nivel educativo: Grado El origen de este texto –materiales docentes- que lleva por título “Introducción al Derecho” ha sido escrito respondiendo a una estricta necesidad docente y por tanto necesariamente pedagógica. En efecto, era totalmente necesario que los alumnos, del Grado de Administración y Dirección de Empresas y otras titulaciones no jurídicas, contasen con un texto para facilitar el estudio de las principales categorías conceptual...

  18. Quadrupole scattering in PrAl2

    Science.gov (United States)

    Sablik, M. J.; Pureur, P.; Creuzet, G.; Fert, A.; Levy, P. M.

    1983-10-01

    We derive the spontaneous anisotropy of the resistivity of the ferromagnetic compound PrAl2 from magnetoresistance measurements on a single crystal of PrAl2. We ascribe this spontaneous anisotropy of the resistivity to scattering of the conduction electrons by the thermal quadrupole disorder and we account for our experimental results by using the theoretical model previously developed by us. We find that quadrupole scattering gives a very important contribution to the total magnetic disorder (spin and quadrupole) resistivity but that only a small part of this quadrupole contribution is anisotropic.

  19. Amyotrofisen lateraaliskleroosin (ALS) fysioterapia : Systemaattinen kirjallisuuskatsaus

    OpenAIRE

    Finne, Ida

    2015-01-01

    Amyotrofinen lateraaliskleroosi eli ALS on harvinainen motoneuronisairaus, jonka ominaispiirteenä on selkäytimen, aivorungon ja aivokuoren motoneuroneiden etenevä degeneraatio ja tuhoutuminen. Tähän parantumattomaan sairauteen sairastuu Suomessa vuosittain noin 120–150 henkilöä. Keskimääräinen sairastumisikä on noin 60 vuotta ja elinikä diagnoosin saamisen jälkeen on noin 3 - 5 vuotta. Fysioterapia on tärkeä osa ALS-potilaan hoitoa ja kuntoutusta. Fysioterapian vaikutut-tavuutta on tästä ...

  20. Aspectos biopsicosociales asociados al embarazo adolescente

    OpenAIRE

    Regina Cogollo Jiménez

    2012-01-01

    Introducción: El embarazo en la adolescencia, es un evento inesperado, sorpresivo. Este artículo establece la importancia de identificar los aspectos biopsicosociales asociados al embarazo adolescente en las embarazadas asistentes al programa de Control Prenatal de una Empresa Social del Estado de nivel 1 en Montería en 2009, para comprender las actitudes y los comportamientos asociados a esta etapa tan temprana. Materiales y Métodos: Es un estudio descriptivo, cuantitativo, de corte transver...

  1. Recent research highlights from the ALS OML

    OpenAIRE

    Yashchuk, Valeriy V.

    2013-01-01

    The main mission of the Optical Metrology Laboratory (OML) at the Advanced Light Source (ALS) is to ensure state-of-the-art performance of beamline optics. New beamlines and instruments laid out in the ALS strategic plan as well as the plan for New Generation Light Source (NGLS) facility all involve increasingly complex optical systems that need ultra-high precision optics to achieve the specifications and goals of their state-of-the art research programs. In order to manufacture, measure, tu...

  2. The wobbler mouse, an ALS animal model

    DEFF Research Database (Denmark)

    Moser, Jakob Maximilian; Bigini, Paolo; Schmitt-John, Thomas

    2013-01-01

    This review article is focused on the research progress made utilizing the wobbler mouse as animal model for human motor neuron diseases, especially the amyotrophic lateral sclerosis (ALS). The wobbler mouse develops progressive degeneration of upper and lower motor neurons and shows striking...... disease mechanism and testing various therapeutic approaches and discuss the relevance of these advances for human ALS. The identification of the causative mutation linking the wobbler mutation to a vesicle transport factor and the research focussed on the cellular basis and the therapeutic treatment of...

  3. The ALS Storage Ring RF System

    International Nuclear Information System (INIS)

    The ALS Storage Ring RF System is characterized by the use of the following features: (1) High power loading of two single cell cavities. (2) The use of a tubular ceramic input window employing aperture coupling. (3) The use of waveguide filters and matchers designed for HOM absorption. (4) A comprehensive HOM monitoring system. (5) The use of waveguide water-wedge loads for the magic tee and circulator loads. The results of cavity measurements and high power tests are reported together with the performance of the system during the commissioning and operation phases of the ALS project. Plans for future window development are discussed

  4. Al-Yawahir Al-Saniyya Fi Sarh-Al-Yarrumiyya, de Al-Ta c Alibi (s.VII-XIV)

    OpenAIRE

    Bellachehab, Ahmed

    1994-01-01

    Edición critica, realizada sobre varios manuscritos, de una interesante fuente gramatical magrebi, del siglo VIII de la hégira XIV de nuestra era. Estudio sobre el autor, at-ta alibi, típico gramático tardío del norte de África, y estudio sobre su producción escrita, en general y en concreto sobre este al-yawahir al-saniyya que es un interesante comentario de la celebre yarrumiyya, comentario hasta hoy inédito que representa un hito en la tradición de estudios gramaticales del occidente islám...

  5. Metamagnetism in Ce(Ga,Al)2

    Indian Academy of Sciences (India)

    K G Suresh; S Radha; A K Nigam

    2002-05-01

    Effect of Al substitution on the magnetic properties of Ce(Ga1-Al)2 ( = 0, 0.1 and 0.5) system has been studied. The magnetic state of CeGa2 is found to be FM with a C of 8 K, whereas the compounds with =0.1 and 0.5 are AFM and possess N of about 9 K. These two compounds undergo metamagnetic transition and the critical fields are about 1.2 T and 0.5 T, respectively at 2 K. These variations are explained on the basis of helical spin structure in these compounds.

  6. Periodistas: el acceso al mercado laboral

    OpenAIRE

    2006-01-01

    El presente estudio analiza la situación profesional de los Licenciados en Periodismo en España. Para ello esta investigación sigue la lógica del proceso de acceso al mercado laboral, es decir, se estudia, en primer lugar, la oferta de egresados y las demandas del sector; a continuación, se analiza la forma en la que un titulado en la Licenciatura de Periodismo accede al mercado laboral y el tiempo que tarda en hacerlo; y por último, se examinan los medios de comunicación en lo...

  7. Surface phonon polariton characteristics of In(0.04)Al(0.06)Ga(0.90)N/AlN/Al(2)O(3) heterostructure.

    Science.gov (United States)

    Ng, S S; Lee, S C; Bakhori, S K Mohd; Hassan, Z; Abu Hassan, H; Yakovlev, V A; Novikova, N N; Vinogradov, E A

    2010-05-10

    Surface phonon polariton (SPP) characteristics of In(0.04)Al(0.06)Ga(0.90)N/AlN/Al(2)O(3) heterostructure are investigated by means of p-polarized infrared (IR) attenuated total reflection spectroscopy. Two absorption dips corresponding to In(0.04)Al(0.06)Ga(0.90)N SPP modes are observed. In addition, two prominent dips and one relatively weak and broad dip corresponding to the Al(2)O(3) SPP mode, In(0.04)Al(0.06)Ga(0.90)N/Al(2)O(3) interface mode, and Al(2)O(3) bulk polariton mode, respectively, are clearly seen. No surface mode feature originating from the AlN layer is observed because it is too thin. Overall, the observations are in good agreement with the theoretical predictions. PMID:20588890

  8. Microstructural defects modeling in the Al-Mo system

    International Nuclear Information System (INIS)

    In this work we have utilized computer simulation techniques to study microstructural defects, such as point defects and interfaces, in the Al-Mo alloy. Such alloy is taken as a model to study the Al(fcc)/U-Mo(bcc) interface. The EAM interatomic potential used has been fitted to the formation energy and lattice constant of the AlMo3 intermetallic. Formation of vacancies for both components Al and Mo and anti-sites, AlMo and MoAl, as well as vacancy migration was studied in this structure. We found that the lowest energy defect complex that preserves stoichiometry is the antisite pair AlMo+MoAl, in correspondence with other intermetallics of the same structure. Our results also suggest that the structure of the Al(fcc)/Mo(bcc) interface is unstable, while that of the Al(fcc)/Al5Mo interface is stable, as observed experimentally. (author)

  9. Liquidus temperatures of Na3AlF6-AlF3-CaF2-KF-LiF-Al2O3 melts

    Directory of Open Access Journals (Sweden)

    Peng J.P.

    2014-01-01

    Full Text Available Temperatures for the primary crystallization of Na3AlF6-AlF3-CaF2-KF-LiF-Al2O3 system adopted in aluminum electrolysis process were determined by thermal analysis. An empirical equation was derived to describe the liquidus temperatures for the primary crystallization of this multicomponent electrolyte system: t/℃=1011 + 0.7w(AlF3 - 0.232w(AlF32 - 7.65w(Al2O3 + 0.523w(Al2O32 - 8.96w(LiF + 0.043w(LiF2 - 3.32w(KF - 0.12w(KF2 - 3.28w(CaF2 +0.037w(CaF22 + 0.091w(AlF3w(LiF + 0.074w(AlF3w(KF + 0.084w(AlF3w(CaF2 - 0.27w(Al2O3w(LiF, where w(AlF3 denotes the mass fraction of excess aluminum fluoride with respect to cryolite. While w(Al2O3 ranges from 2% to 4%, w(LiF, w(KF and w(CaF2 from 0 to 7%, and the molar ratio of NaF/AlF3 from 2.2 to 3.

  10. An impedance study of complex Al/Cu-Al{sub 2}O{sub 3} electrode

    Energy Technology Data Exchange (ETDEWEB)

    Denisova, J; Katkevics, J; Viksna, A [Faculty of Chemistry, University of Latvia, Kr. Valdemara Str. 48, Riga, LV-1013 (Latvia); Erts, D, E-mail: arturs.viksna@lu.lv [Institute of Chemical Physics, University of Latvia, Kronvalda blvd. 4, Riga, LV-1586 (Latvia)

    2011-06-23

    Electrochemical impedance spectroscopy (EIS) was used to investigate different Cu deposition regimes on Al surface obtained by internal electrolysis and to characterize properties of fabricated electrodes. EIS experimental data confirmed that Cu deposition by internal electrolysis is realized and the complex electrode system is obtained. The main difficulty in preparation of Al/Cu electrodes is to prevent aluminium oxidation before and during electrochemical deposition of Cu particles. In this work NaCl, CH{sub 3}COONa, K{sub 2}SO{sub 4}, mono- and diammonium citrate electrolytes were examined to determine their suitability for impedance measurements. Al/Cu-Al{sub 2}O{sub 3} electrode composition was approved by equivalent circuit analysis, optical and scanning electron microscope methods. The most optimal Cu deposition mode using internal electrolysis was determined. The obtained results are promising for future electrochemical fabrication of nanostructures directly on Al surfaces by internal electrolysis.

  11. FABRICATION OF Al/Al2O3 FGM ROTATING DISC

    Directory of Open Access Journals (Sweden)

    A. B. Sanuddin

    2012-06-01

    Full Text Available This study presents a method of fabricating a disc made of Al/Al2O3 functionally graded materials (FGM, using a powder metallurgy manufacturing process. The aim is to develop a processing method for a rotating disc made of FGM, by stacking the slurry, layer by layer in a radial direction. A three-layer functionally graded material of Al/Al2O3 is fabricated with compositions of 10, 20, 30 vol.% Al2O3. The ceramic composition increases from the discs inner (centre to the outer. The combination of these materials can offer the ability to withstand high temperature conditions whilst maintaining strength in extreme environments.

  12. In situ microscopy of rapidly heated nano-Al and nano-Al/WO3 thermites

    Science.gov (United States)

    Sullivan, Kyle T.; Chiou, Wen-An; Fiore, Richard; Zachariah, Michael R.

    2010-09-01

    The initiation and reaction mechanism of nano-Al and nano-Al thermites in rapid heating environments is investigated in this work. A semiconductor-based grid/stage was used, capable of in situ heating of a sample from room temperature to 1473 K, and at a rate of 106 K/s, inside an electron microscope. Nano-Al was rapidly heated in a transmission electron microscope, and before and after images indicate that the aluminum migrates through the shell, consistent with a diffusion-based mechanism. A nano-Al/WO3 composite was then heated in a scanning electron microscope. The results indicate that a reactive sintering mechanism is occurring for the nano-Al/WO3 thermite, as the products are found to be in surface contact and significantly deformed after the heating pulse.

  13. Serious Flaws in Korf et al.'s Analysis on Time Complexity of A*

    CERN Document Server

    Dinh, Hang

    2008-01-01

    Understanding the effect of a heuristic on the time complexity of the well-known A* search algorithm has been a subject of a large research body in AI. Among those researches is Korf et al.'s analysis (Korf & Reid, 1998; Korf et al., 2001; Korf, 2000a; Korf, 2000b), which concluded that the effect of a heuristic is to reduce the effective depth rather than effective branching factor. Since this conclusion conflicts with both previous analysis and recent analysis by other authors, we try to investigate the causes of such contradictions and finally find out that Korf et al.'s analysis has many serious flaws from which their main conclusion was drawn.

  14. Tensile deformation behavior of a sub-micrometer Al2O3/6061Al composite

    International Nuclear Information System (INIS)

    A 0.3 μm Al2O3/6061Al composite with 33% volume fraction of Al2O3 was fabricated by the patented squeeze-casting technology. The tensile properties were studied, and the dynamic tensile deformation behavior was investigated by an in situ TEM tensile technique. The as-cast composite exhibits excellent tensile properties with a fracture strength of 504 MPa, and the strength increases to 579 MPa after a T6 treatment. The high strength is mainly attributed to the dispersion strengthening effect of the finer sub-micrometer Al2O3 particles. Dynamic transmission electron microscopy indicates that micro-cracks initiate and propagate mainly in the matrix. The Al2O3 particles can hinder the growth and deflect the cracks, but the resistance of the particles to crack propagation is small. The propagation stage is accordingly short, leading to the fracture of the composite

  15. Different magnetic behaviour of the Kondo compounds Al3Ce and Al11Ce3

    International Nuclear Information System (INIS)

    Neutron diffraction experiments on the Al3Ce and Al11Ce3 compounds have been performed on the multidetector of the I.L.L. high flux reactor. No magnetic structure has been detected on the Al3Ce compound down to 20 mK. This confirms the non magnetic ground state of Al3Ce. For Al11Ce3, two magnetic structures have been observed: a ferromagnetic one at 4.2 K and an antiferromagnetic one at 2 K. The antiferromagnetic structure, which corresponds to a propagation vector (0,0,1/3), implies a strong reduction of the magnetic moment of determined sites; this reflects the Kondo character of the compounds

  16. InAlGaAs/AlGaAs quantum wells: line widths, transition energies and segregation

    DEFF Research Database (Denmark)

    Jensen, Jacob Riis; Hvam, Jørn Märcher; Langbein, Wolfgang

    We investigate the optical properties of InAlCaAs/AlGaAs quantum wells pseudomorphically grown on GaAs using molecular beam epitaxy (MBE). The transition energies, measured with photoluminescence (PL), are modelled solving the Schrodinger equation, and taking into account segregation in the group...... III sublattice. From a fit to the transition energies, an empirical band gap relation for InAlGaAs is found, in the composition range relevant for growth on GaAs. The PL lines at low temperature (T = 10 K) are broadened due to random alloy fluctuations and an interface roughness of 1.1 monolayers....... Finally, the use of InAlGaAs/AlGaAs quantum wells for making strained T-shaped quantum wires is demonstrated. (C) 2000 Elsevier Science B.V. All rights reserved....

  17. Effect of stress on the Al composition evolution in AlGaN grown using metal organic vapor phase epitaxy

    Science.gov (United States)

    He, Chenguang; Qin, Zhixin; Xu, Fujun; Zhang, Lisheng; Wang, Jiaming; Hou, Mengjun; Zhang, Shan; Wang, Xinqiang; Ge, Weikun; Shen, Bo

    2016-05-01

    Two series of AlGaN samples with different stresses were designed to investigate the effect of stress on the Al composition. X-ray diffraction reciprocal space mapping (XRD RSM) demonstrated that the AlGaN epilayers with different stresses have large Al composition differences despite the same growth conditions. The largest Al composition difference reached up to 21.3%, which was also confirmed using secondary ion mass spectroscopy (SIMS). This result is attributed to a large stress discrepancy in the AlGaN epilayers. Finally, the dependences of the solid-phase Al composition on the gas-phase Al composition under different stresses were systematically analyzed.

  18. The constitution of alloys in the Al-rich corner of the Al-Si-Sm ternary system

    International Nuclear Information System (INIS)

    The constitution of alloys and the liquidus surface in the Al-rich corner of the Al-Si-Sm ternary system were determined by the examination of controlled heated and cooled specimens, as well as heat-treated specimens by means of optical and scanning electron microscopy, energy-dispersive X-ray spectroscopy, differential thermal analysis and X-ray diffraction. The Al-rich corner of the Al-Si-Sm ternary system comprises five regions of primary crystallisation (αAl, βSi, Al3Sm, Al2Si2Sm and AlSiSm) with following characteristic invariant reaction sequences: ternary eutectic reaction L → αAl + βSi + Al2Si2Sm, and two liquidus transition reactions, i. e., L + Al3Sm → αAl + AlSiSm, and L + AlSiSm → αAl + Al2Si2Sm. Along with the position of ternary eutectic and both interstitial points in the Al-rich corner of the Al-Si-Sm ternary system, the temperatures for each reaction were determined. (orig.)

  19. Microscopic phase field study of the antisite defect of Ni3 Al in binary Ni-Al alloys

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The temporal evolution feature of a microscopic phase field model is utilized to study the antisite defects of L1 2-Ni 3 Al;this is quite different from other physicist’ interests.There are mainly two points in brief.Firstly,antisite defects Ni Al and Al Ni ,which are caused by the deviation from the stoichiometric Ni 3 Al,coexist in the Ni 3 Al phase.The surplus Ni atom in the Ni-rich side is prone to substitute Al thus producing the antisite defect Ni Al that maintains the stability of the L1 2 structure.In other case,the surplus Al atom in the Al-rich side is accommodated by a Ni sublattice consequently giving rise to antisite defect Al Ni .The calculated equilibrium occupancy probability of Ni Al is much higher than that of Al Ni .This point is generally in line with other theoretical and experimental works.Additionally,both Ni Al and Al Ni have a strong negative correlation to time step during the disorder-order transformation.Since the initial value of Ni Al and Al Ni on each site of the matrix is right at the concentration that we set,we can observe the decrease process of Ni Al and Al Ni from the initial disordered high anti-structure state to their respective equilibrium state,i.e.to the result of the ordering process further coarsening.

  20. The modulation structure induced changes in mechanical properties of TiAlN/Al2O3 multilayers

    International Nuclear Information System (INIS)

    TiAlN/Al2O3 multilayers which had different separate layer thickness of TiAlN or Al2O3 were synthesized by sputtering Ti3Al and Al2O3 targets with N2 and Ar gases. The influence of modulation periods and modulation ratios on structure and properties of TiAlN/Al2O3 multilayers was investigated using scanning electron microscopy, X-ray diffraction, X-ray Photoelectron Spectroscopy, surface profiler, and nanoindenter. Compared to TiAlN layer with only (2 0 0) preferred orientation, TiAlN/Al2O3 multilayers were crystallized with orientations in the TiAlN (1 1 1), TiAlN (2 2 2) and AlN (1 0 0). Besides, weak Al2O3 (0 2 2) orientation is observed, when modulation period is 8.9 nm. The maximum hardness about 36.6 GPa was obtained at modulation period of 10.4 nm and modulation ratio of 10:1. The hardness and the toughness of TiAlN/Al2O3 multilayers increase as individual TiAlN layer thickness increases