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Sample records for acondicionamiento con calor

  1. Dimensionamiento de intercambiadores de calor de coraza y tubos, con ayuda de computador

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    Gabriel Eduardo Rocha Camino

    2011-02-01

    Full Text Available En este trabajo se plantea el problema de optimizar el diseño de un intercambiador de calor del tipo coraza y tubos, y se propone un método para resolverlo, con base en la técnica del "estudio paramétrico de la respuesta". Además, se muestra la necesidad de utilizar el computador como herramienta para Implementar dicho método, y se describe un programa escrito con tal fin.

  2. The use of cooling systems with desiccants in the condition of buildings; El uso de sistemas de enfriamiento con desecantes en el acondicionamiento de edificaciones

    Energy Technology Data Exchange (ETDEWEB)

    Alpuche Cruz, Maria G; Avila Segura, Francisco [Centro de Investigacion en Energia, UNAM, Temixco, Morelos (Mexico)

    2000-07-01

    In this document some papers about the development of solid and liquid desiccant cooling systems and dehumidification are analyzed. In a desiccant cooling cycle, the desiccant reduces the quantity of humidity of the air and temperature is decreases by others components such as heat exchangers, cooling evaporatives or conventional coolers. The main advantage of this systems is the capacity to use a low-grade thermal energy. These systems are being used in residence and commercial constructions to reduce energy and to optimize costs, however the initial cost is significantly higher that the conventional cooling systems. Recent studies have been focused in analyzing desiccant cooling systems, through computer modeling. [Spanish] En este documento se analizan algunas publicaciones sobre el desarrollo de los sistemas de enfriamiento y deshumidificacion con desecantes solidos y liquidos. En el ciclo de enfriamiento en el desecante, el desecante reduce la cantidad de humedad del aire y la temperatura se reduce por medio de otros componentes tales como intercambiadores de calor, enfriadores evaporativos o enfriadores convencionales. La ventaja principal que ofrecen estos sistemas es la capacidad de utilizar una baja cantidad de energia termica. Estos sistemas estan siendo utilizados en edificaciones habitacionales y comerciales para reducir el consumo de energia y optimizar costos, sin embargo el costo inicial es significativamente mas alto que los sistemas de enfriamiento convencionales. Estudios recientes se han enfocado en analizar estos sistemas de enfriamiento con desecantes, a traves de la modelacion por computadora.

  3. Calor: Una Propuesta Didáctica Constructivista con Enfoque de Ciencia Integrada

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    Castillo Alberto de L.

    2002-01-01

    Full Text Available Realizamos un estudio comparativo entre dos diseños didácticos constructivistas para la enseñanza del tema Calor en estudiantes de carreras en ciencias naturales. Uno con un enfoque de ciencia integrada y el otro con un enfoque no integrador. En el primer diseño el alumno construye su propio conocimiento resolviendo situaciones problemáticas relacionadas a la biología y el medio-ambiente, que le permite analizar y relacionar los conceptos involucrados, mientras que en el segundo construye su conocimiento a través de la resolución de situaciones problemáicas físicas pero no biológicas. Concluimos que el primer diseño favorece en los alumnos la construcción de una estructura cognitiva del tipo integrada, que les facilita internalizar y transferir los conceptos físicos a problemas concretos de su especialidad.

  4. Research on heat pumps in Mexico operating with geothermal energy and waste heat; Investigacion sobre bombas de calor en Mexico operando con energia geotermica y calor de desecho

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Gutierrez, A; Barragan-Reyes, R.M; Arellano-Gomez, V [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: aggarcia@iie.org.mx

    2008-01-15

    The Instituto de Investigaciones Electricas and the Comision Federal de Electricidad have done research and development (R&D) on heat pumps (HP) in past years. Tested systems include mechanical compression, absorption and heat-transformers. The main R&D aspects on HP are briefly described, and also a more detailed description about three of the main studies is presented: (a) a mechanical compression HP of the water-water type operated with low-pressure geothermal steam at the Los Azufres; Mich., geothermal field, and designed for purification of brine; (b) an absorption HP for cooling and refrigeration operating with ammonia-water and low-enthalpy geothermal energy, which was tested in the Los Azufres and Cerro Prieto, BC, geothermal fields; and (c) a heat-transformer by absorption-Absorption Heat Pump Type II-tested to assess the performance of several ternary solutions as work fluids. Plans exist to install and test a geothermal heat pump at Cerro Prieto or Mexicali, BC. [Spanish] El Instituto de Investigaciones Electricas y la Comision Federal de Electricidad han realizado trabajo de investigacion y desarrollo (I&D) sobre bombas de calor (BC) en el pasado. Los sistemas probados incluyen compresion mecanica, absorcion y transformadores termicos. Este trabajo describe brevemente los principales aspectos de I&D sobre bombas de calor en forma general, y se da una descripcion mas detallada de tres de los principales estudios: (a) una BC por compresion mecanica tipo agua-agua disenada para purificacion de salmueras operando con vapor geotermico de baja presion en el campo geotermico de Los Azufres, Mich.; (b) una BC por absorcion para enfriamiento y refrigeracion operando con amoniaco-agua y energia geotermica de baja entalpia, la cual fue probada en los campos geotermicos de Los Azufres y Cerro Prieto, BC; y (c) un transformador termico por absorcion -llamado Bomba de Calor por Absorcion Tipo II--, el cual fue probado para evaluar el comportamiento de diversas

  5. Estudios sobre el calor de hidratación desarrollado en morteros con materiales puzolánicos: naturales y subproductos industriales

    OpenAIRE

    Sánchez de Rojas, María Isabel; Frías Rojas, Moisés; Rivera, J

    2000-01-01

    [ES] Con la incorporación de materiales con características puzolánicas en morteros y hormigones se puede rebajar el calor desarrollado en las reacciones de hidratación. Sin embargo, la disminución en el calor de hidratación no es directamente proporcional a la cantidad de cemento sustituido, esto es debido al aporte de calor generado en la reacción puzolánica, de forma que con materiales muy activos, como el humo de sílice o las rocas opalinas, incluso se incr...

  6. Acondicionamiento térmico de semillas en la germinación, emergencia, vigor y etapa vegetativa de albahaca (Ocimum basilicum L.

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    Mirella Romero-Bastidas

    2016-01-01

    Full Text Available La importancia económica de la albahaca (Ocimum basilicum L. a nivel mundial, ha impulsado la búsqueda de estrategias como el acondicionamiento previo a la semilla para mejorar los índices de vigor en la planta, relacionados con un rendimiento mayor, calidad y tolerancia a algún tipo de estrés. El objetivo del presente estudio fue determinar el umbral óptimo de acondicionamiento de la semilla con diferentes gradientes de escarificación sobre las características de vigor relacionadas a variables morfométricas y fisiológicas en plántulas de albahaca durante las etapas de germinación, emergencia y desarrollo vegetativo inicial. Semillas de albahaca variedad Nuffar se sometieron a tratamientos de acondicionamiento térmico mediante la exposición de calor seco, en cuatro gradientes de temperatura (40, 50, 60 y 70°C y diferentes intervalos de tiempo (30, 60 y 90 min y un tratamiento control (25°C, mediante un diseño completamente al azar con arreglo factorial con cuatro y/o cinco repeticiones. Los resultados mostraron que la temperatura y los tiempos de exposición afectaron significativamente (p≤0.05 las variables de tasa y porcentaje de germinación y emergencia, así como las variables morfométricas y fisiológicas de la planta. En la etapa de germinación, el tratamiento de 70ºC afectó negativamente la respuesta de la planta en todas las variables evaluadas, independientemente de los tiempos de exposición, mientras que los tratamientos de 40, 50 y 60ºC fueron iguales al control. En la etapa de emergencia, se observó una tendencia determinada hacia el tratamiento de 60ºC por un tiempo de exposición de 60 min, el cual mejoró significativamente las características de vigor. Sin embargo, no fue así para el tratamiento de 70ºC, el cual provocó disminución en las variables evaluadas. Asímismo, durante la etapa vegetativa inicial, la exposición a 60ºC por 30 y 60 min mejoró significativamente las variables morfo fisiol

  7. Refrigeración local de vehículos con calor excedente

    OpenAIRE

    Matarazzo Zinoni, Gustavo

    2014-01-01

    RESUMEN: Existe una gran cantidad de energía que normalmente desperdiciamos cuando trabajamos con máquinas térmicas tales como los motores de nuestros vehículos. ¿Por qué no empezamos a aprovechar mejor esta energía? Los gases de escape del motor de nuestro automóvil salen con una temperatura y una velocidad muy alta, es decir, salen con mucha energía. ¿Por qué la desperdiciamos? Por otro lado, cuando encendemos el aire acondicionado de nuestro vehículo quitamos eficiencia al motor porque tom...

  8. Desarrollo de una golosina tipo gomita reducida en calorías mediante la sustitución de azúcares con Stevia rebaudiana B

    OpenAIRE

    Irma Aranda-González; Óscar Tamayo-Dzul; Enrique Barbosa-Martín; Maira Segura-Campos; Yolanda Moguel-Ordoñez; David Betancur-Ancona

    2015-01-01

    Las gomitas son golosinas de consumo difundido entre personas de diferentes edades aunque principalmente por los niños. La formulación de este producto requiere azúcar que contribuye a su sabor y consistencia, aunque con el efecto indeseable de incrementar su índice glicémico y calorías provenientes de azúcares simples; se sabe que el consumo de productos con estas dos últimas características están relacionados con la obesidad infantil, la cual es una enfermedad en crecimiento a nivel mundial...

  9. Research and technological development on heat pumps in Mexico operating with geothermal energy; Investigacion y desarrollo tecnologico sobre bombas de calor en Mexico operando con energia geotermica

    Energy Technology Data Exchange (ETDEWEB)

    Garcia Gutierrez, Alfonso; Barragan Reyes, Rosa Maria; Arellano Gomez, Victor Manuel [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2008-07-01

    The Instituto de Investigaciones Electricas (IIE) and the Comision Federal de Electricidad (CFE) carried out in the past an extensive work of research and development (R&D) on heat pumps (HP). The systems tried on include heat pumps by mechanical compression, thermal absorption and thermal transformers. This paper briefly describes the main aspects of R&D on heat pumps and presents a more detailed description of three of the main studies: a) a Heat Pump (HP) by mechanical compression water-water type, designed for brine purification, operating with low pressure geothermal steam at the geothermal field Los Azufres, Michoacan, Mexico; b) a HP by absorption for cooling and refrigeration, operating with ammoniac/water and low enthalpy geothermal energy, which was tested in the geothermal fields of Los Azufres, Michoacan and Cerro Prieto, Baja California, and c) a thermal transformer by absorption, named Heat Pump by Absorption Type 2, which was tested to evaluate the behavior of diverse ternary solutions as working fluids. To date, there are plans to install and test a geothermal heat pump (connected to the subsoil), in Cerro Prieto, Mexicali, Baja California, Mexico. [Spanish] El Instituto de Investigaciones Electricas (IIE) y la Comision Federal de Electricidad (CFE) realizaron un trabajo extenso de investigacion y desarrollo (I&D) sobre bombas de calor (BC) en el pasado. Los sistemas que se probaron incluyen bombas de calor por compresion mecanica, absorcion y transformadores termicos. Este trabajo describe brevemente los principales aspectos de I&D sobre bombas de calor y se da una descripcion mas detallada de tres de los principales estudios: a) una Bomba de Calor (BC) por compresion mecanica tipo agua-agua, disenada para purificacion de salmueras, operando con vapor geotermico de baja presion en el campo geotermico de Los Azufres, Michoacan; b) una BC por absorcion para enfriamiento y refrigeracion, operando con amoniaco/agua y energia geotermica de baja entalpia

  10. Acondicionamiento de cavidades terapéuticas

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    Berástegui, Esther; Pumarola Suñé, José; Roig Cayón, Miguel

    1997-01-01

    La aparición de materiales nuevos obliga a replantearse la preparación del sustrato dental para recibir el material de obturaión. El objetivo de estudio fue analizar la situación actual en lo referente al acondicionamiento de cavidades en operatoria dental previa a la obturación. Para ello se ha revisado la literatura más moderna en tres aspectos: la tinción de la caries, desinfección y la protección del complejo pulpodentinario. Después del estudio del tema llegamos a la conclusión que la de...

  11. Solución numérica de procesos de transferencia de calor en aleaciones con condiciones de contorno no lineales

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    Alhama, F.

    2005-12-01

    Full Text Available Thermal properties of a great number of alloys, especially specific heat, show a sharply temperature dependence both during the phase change and the allotropic transformations. This fact, in conjunction with the existence of convection or radiation boundary conditions, or both simultaneously, increase the complexity of the transient heat transfer problem because of the inherent no linearity. The numerical model proposed for the solution of this problem is able to assume the above hypothesis as well as the temperature dependencies of the thermal conductivity. Applications to alloys are presented.

    Las propiedades térmicas de numerosas aleaciones, especialmente la capacidad calorífica, acusan una marcada dependencia con la temperatura tanto en los cambios de fase como en las transformaciones alotrópicas. Este hecho, junto con la aplicación de condiciones de contorno de convección, radiación o ambas, simultáneamente, aumentan la complejidad del problema de transferencia de calor en los procesos transitorios debido a la no linealidad inherente. El modelo numérico propuesto para la solución de este problema es capaz de asumir las hipótesis anteriores así como las posibles dependencias de la conductividad térmica con la temperatura. Se presentan aplicaciones a procesos térmicos en aleaciones.

  12. FLUJO INTERNO MIXTO CON DIFUSIÓN DOBLE DE CALOR Y MASA EN UNA CAVIDAD RECTANGULAR MIXED INTERNAL FLOW WITH DOUBLE DIFFUSION OF HEAT AND MASS

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    Carlos H Salinas Lira

    2008-09-01

    Full Text Available El presente trabajo muestra resultados de transporte de calor y masa (Doble al interior de una cavidad rectangular ocasionado por un flujo convectivo forzado y natural (Mixto. El modelo matemático consta de las ecuaciones de Navier-Stokes para describir el flujo laminar de un fluido incompresible. Además es modelado el transporte de calor y masa a través de dos ecuaciones diferenciales lineales de segunda orden, incorporando en forma lineal los efectos de los gradientes de concentración y de temperaturas. El modelo matemático es resuelto numéricamente a través del Método de Volúmenes Finitos descrito en coordenadas curvilíneas y variables colocalizadas, representando los términos difusivos a través de diferencia central y usando un esquema potencial para los términos convectivos. Se muestran resultados originales de patrones de flujo: Isotermas, isoconcentraciones y números de Nusselt y de Sherwood en regiones características para el problema de flujo interno mixto con difusión de calor y masa.The present work shows the relationship of the transport of heat and mass (double in a rectangular cavity caused by a forced and natural convection. The mathematical model consists of the Navier-Stokes equations to describe the incompressible laminar flow. The transport of heat and mass are modelled through two second order no-linear differential equations, incorporating in linear way the effects of gradients of concentrations and temperature. The mathematical problems is solved numerically through the Finite Volumes Method, in curvilinear coordinated and co-located variables, representing the diffusion through central difference and using a potential schemes for the convection terms. Original results of flow models are shown: Isotherms, isoconcentrations and numbers of Nusselt and Sherwood in characteristic regions for the mixed internal flow problem with heat and mass are shown.

  13. Control en modo deslizante aplicado a sistemas de acondicionamiento de potencia de satélites

    OpenAIRE

    Calvente Calvo, Francisco Javier

    2001-01-01

    El sistema de acondicionamiento de potencia es clave para el funcionamiento correcto del resto de sistemas eléctricos de un satélite. Los reguladores conmutados continua - continua son las piezas que enlazan los paneles solares y las baterías con el bus principal de alimentación. La estabilidad, precisión y robustez del sistema de control son fundamentales en el diseño de esos convertidores.Desde el punto de vista de los especialistas en control, los convertidores conmutados son sistemas de e...

  14. Acondicionamiento físico precompetitivo para el tenis

    OpenAIRE

    Cetina Pinilla, Jefferson

    2015-01-01

    El Acondicionamiento Físico Precompetitivo para el Tenis, es una propuesta de una nueva forma de preparación física del tenista minutos antes de una competencia de tenis en cualquiera de los tres tipos de superficie mas jugadas en el mundo (polvo de ladrillo, hierba y cemento). Esta tesis retoma desde la bibliografía referentes de los momentos previos a una competencia como "Calentamiento" y preparación del deportista como "Acondicionamiento Físico"; se hablará también del aspecto fisiológico...

  15. Estudio macroscópico y genético de piezas dentarias sometidas a calor con fines forenses

    OpenAIRE

    Sioli Durán, José Manuel

    2014-01-01

    Introducción: muchos casos forenses precisan la interpretación de cadáveres humanos quemados, carbonizados y/o incinerados, como es el caso de accidentes aéreos, automovilísticos, atentados con bombas, cremaciones ilícitas, y en menor medida, en homicidios, suicidios, e incluso muertes accidentales. En situaciones extremas, donde la acción del fuego daña o degrada excesivamente la totalidad de los tejidos, suelen ser los huesos y más aún los dientes, la única evidencia disponible en los proce...

  16. Transferencia de calor incrementada en espacios anulares con elementos helicoidales insertados//Review of augmentation techniques for heat transfer coefficient in annular spaces using helical elements

    OpenAIRE

    Josué Imbert‐González; Octavio García‐Valladares; Viedma, A.; Reinaldo Guillen‐Gordín

    2014-01-01

    La transferencia de calor incrementada por métodos pasivos se emplea en diversosintercambiadores de calor de alta efectividad. El objetivo del trabajo presentado fue la evaluación del estado de las investigaciones en el campo de la transferencia de calor mejorada en espacios anulares, a partir del empleo de elementos turbulizadores helicoidales como técnicas pasivas. La revisión se centró en el empleo de láminas helicoidales y espirales, la obtención de ecuaciones de correlación del coeficien...

  17. Acondicionamiento osmótico en semilla de Brassica oleracea L.

    OpenAIRE

    J. E. Rodríguez-Pérez; J. Martínez-Solís; R. Mora-Aguilar; M. F. Ireta-Hernández

    2006-01-01

    Las brassicaceas, como brócoli, coliflor y col, son cultivos importantes en México por su calidad nutricional, propiedades anticancerígenas y generación de divisas por la exportación de su producción. Para determinar el tratamiento óptimo de acondicionamiento osmótico y su efecto en la calidad fisiológica, se sometió semilla de brócoli, coliflor y col a soluciones de Polietilenglicol 6000 con potencial osmótico de 0, -5, -10, -15 y -20 atm durante 8, 16 y 24 h, además de un testigo absoluto (...

  18. Thermal and friction drop characteristic of heat exchangers with elliptical tubes and smooth fins//Caracterización térmica e hidráulica de intercambiadores de calor con tubos elípticos y aletas lisas

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    Rubén Borrajo-Pérez

    2012-09-01

    Full Text Available Pressure drop and heat transfer are the most important parameters in compact heat exchanger. There is a lack of information in the literature about heat exchanger with elliptical tube. The objective of this work was the experimental characterization of compact heat exchangers models using elliptical tube with eccentricity of 0,5 and smooth fins. The Reynolds numbers and the spacing were varied and always inside laminar regime. The experiments were conducted in an open wind tunnel using sublimation of naphthalene and the heat and mass transfer analogy. As results, the average and local Nusselt number and friction factor for 36 models were obtained. Correlations for Colburn and friction factors were presented. This correlations were obtained for 200calor son importantes parámetros en intercambiadores de calor. Existe falta de información cuando de intercambiadores de calor y tubos elípticos se trata. El objetivo del trabajo fue caracterizar experimentalmente modelos de intercambiadores de calor con tubos elípticos yaletas lisas. El numero de Reynolds y los espaciamientos fueron variados, dentro del régimen laminar. Los experimentos fueron desarrollados en un túnel de viento de circuito abierto usando la sublimación de naftaleno y la analogía calor y masa. Los números de Nusselt medio, locales y el factor de fricción fueronobtenidos en forma de correlaciones de Factores de Fricción y Colburn. Las correlaciones, validas para 200

  19. Indicadores Antropométricos en un Centro de Acondicionamiento Físico Urbano de la Provincia de Heredia

    OpenAIRE

    Gustavo Rivera Cabezas; Pedro Ureña Bonilla

    2014-01-01

    El propósito de este estudio fue identificar los valores antropométricos y su relación con la salud en los usuarios del Centro de Acondicionamiento Físico (CAF) de la Escuela de Ciencias de la Salud y Calidad de Vida (CIEMHCAVI) de la Universidad Nacional. Se analizó 1000 expedientes, aunque por razones de ausencia de datos se trabajó con 563. La información recopilada correspondió a 315 hombres y 248 mujeres con edad promedio de 28,5 ± 11,3 y de 30,2 ± 11,3 años, respectivamente. Cada expe...

  20. ESTUDIO NUMÉRICO DE LA CONVECCIÓN NATURAL EN UNA CAVIDAD CUADRADA EN 2-D CON INTERFASE FLUIDO-MEDIO POROSO Y GENERACIÓN DE CALOR

    OpenAIRE

    H. Jiménez-Islas; M. Calderón-Ramírez; J. L. Navarrete-Bolaños; J. E. Botello-Álvarez; G. M. Martínez-González; F. López-Isunza

    2009-01-01

    Se estudió numéricamente el fenómeno de convección natural bidimensional en una cavidad cuadrada que contiene dos regiones horizontales formadas por un fluido homogéneo y un medio poroso isótropo, el cual presenta generación de calor. Para la modelación, se utilizó el enfoque de dominio simple con un parámetro binario para que las ecuaciones de momentum y de energía tengan validez en todo el dominio. Las ecuaciones de transporte se discretizaron mediante colocación ortogonal y el sistema de...

  1. Transferencia de calor incrementada en espacios anulares con elementos helicoidales insertados//Review of augmentation techniques for heat transfer coefficient in annular spaces using helical elements

    Directory of Open Access Journals (Sweden)

    Josué Imbert‐González

    2014-08-01

    Full Text Available La transferencia de calor incrementada por métodos pasivos se emplea en diversosintercambiadores de calor de alta efectividad. El objetivo del trabajo presentado fue la evaluación del estado de las investigaciones en el campo de la transferencia de calor mejorada en espacios anulares, a partir del empleo de elementos turbulizadores helicoidales como técnicas pasivas. La revisión se centró en el empleo de láminas helicoidales y espirales, la obtención de ecuaciones de correlación del coeficiente de transferencia de calor incrementado, el coeficiente de fricción y la evaluación que se realiza de este proceso por parte de diferentes autores. El análisis crítico permitió realizar valoraciones integradas y recomendar sobre los aspectos que podrían ser analizados en el futuro en esta temática.Palabras claves: transferencia de calor incrementada, láminas helicoidales, espirales, espacios anulares, métodos pasivos._______________________________________________________________________________AbstractThe transfer enhancement by passive methods is used in several heat exchanger of high effectiveness. The objective of the presented work was the evaluation of the state of the investigations in heat transfer enhancement in annular spaces, from the employment of elements helical. The revision was centered in the employment of twisted tape and wire coil in spiral, the equations of correlation obtained of the coefficient of transfer of increased heat, the coefficient of friction and the evaluation that was carried out of this process on the part of different authors. From the critical analysis of the published results, the authors recommend on the topics that can be analyzed in the future in this area.Key words: heat transfer enhancement, twisted tape, helical springs, annular spaces, passive methods.

  2. Automobilismo: no calor da competição Automovilismo: en el calor de la competición Car racing: in the heat of competition

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    Luiz Oswaldo Carneiro Rodrigues

    2004-06-01

    ções ambientais do autódromo no dia de sua morte.El presente artículo cuestiona el papel del calor como un factor de riesgo adicional para el accidente que sufrió Ayrton Senna. El automovilismo de competición constituye un desafío biológico, una situación estresante desde el punto de vista mental y físico. El mantenimiento de la performance depende de la disponibilidad de los carbohidratos y del oxígeno, hidratación adecuada y temperatura interna constante entre 37 y 38 grados centígrados. La disipación de calor producido por el metabolismo que ocurre a través del aumento del flujo de sangre para mantener la temperatura cerebral constante constituye un problema permanente. Se ha verificado experimentalmente que la energía requerida para conducir un auto de carrera es similar a la requerida para practicar un deporte como el voleibol. Durante una carrera, el individuo está expuesto a un microambiente caliente dentro de la cabina que puede llegar hasta los 50 grados centígrados generado por fuentes de calor como las mecánicas y las ambientales. El bloque del sudor por el mameluco resulta en humedad y disconfor personal, lo que implica un mayor esfuerzo personal para conducir el auto. Las medidas contra el calor comienzan antes de la carrera, cuidando el estado nutricional, la hidratación y principalmente el acondicionamiento físico a través de ejercicios aeróbicos regulares y adecuados, que permitan aumentar la capacidad de trabajo y la tolerancia al calor, lo que resulta en una menor fatiga durante la carrera. Otro procedimiento importante debería ser la aclimatación de los pilotos en ambientes calientes y húmedos. Se debe realizar lo posible en el acondicionamiento del vehículo para respetar el sistema de banderas de advertencia para los riesgos de hipertermia. En conclusión, si ahora Ayrton Senna fuera un individuo con mayor riesgo de desarrollar hipertermia, independientemente de otras causas, no parece haber habido tiempo suficiente en la carrera para

  3. Evaluación de un sistema de ventilación mecánica de una vivienda con recuperación de calor del aire

    OpenAIRE

    Castro Núñez, David

    2013-01-01

    En este trabajo se pretenden evaluar distintas actuaciones destinadas a la reducción de la demanda térmica de una vivienda unifamiliar situada en Gijón. Para ello se analizará el comportamiento térmico del edificio en distintos supuestos y se valorarán distintas actuaciones desde el punto de vista de la eficiencia energética, económica y ambiental. Entre estas actuaciones se incluyen la recuperación de calor, la reducción de los requerimientos de ventilación, el aumento del espesor de aislami...

  4. Acondicionamiento de la plaza del viejo mercado en Rouen – Francia

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    Arretche, L.

    1980-06-01

    Full Text Available The aim sought in conditioning the Old Market square of Rouen has been to integrate three elements of very different functions in a harmonious unit. These are: — the church — the covered market, and — the Joan of Arc national monument. The various frameworks are based on the traditional naval construction and are made up of tuned surfaces: hyperbolic paraboloids made in wood. The thirteen XVI century stained glass windows miraculously saved from the destruction of Saint Vincent's Church are an outstanding feature.

    Con el acondicionamiento de la plaza del Viejo Mercado de Rouen se ha pretendido integrar en un conjunto armonioso tres elementos de tan distintas funciones como son: — la iglesia, — el mercado cubierto, y — el monumento nacional a Juana de Arco. Los diversos entramados se basan en la construcción naval tradicional y están constituidos por superficies regladas: paraboloides hiperbólicos hechos de madera. Destacan en el conjunto las trece vidrieras del siglo XVI, salvadas milagrosamente de la destrucción de la iglesia de San Vicente.

  5. Diseño y acondicionamiento acústico de la sala de grabación musical de Basic Productions en Valencia

    OpenAIRE

    CORBI ALBELLA, DIDAC

    2013-01-01

    El objetivo de este proyecto es el estudio del comportamiento del sonido en recintos cerrados para después realizar con éxito el diseño y acondicionamiento de la sala de grabación de los estudios Basic Productions. Esta sala será utilizada para grabaciones musicales por lo que se tendrá en cuenta esto a la hora de valorar las condiciones acústicas más adecuadas para este. Se considerará como objetivo principal el control del tiempo de reverberación para obtener uno adecuado al ...

  6. EFECTO DE UN PROGRAMA DE HIDROQUINESIA Y ACONDICIONAMIENTO FÍSICO EN LA MOVILIDAD ARTICULAR DE ADULTAS MAYORES

    OpenAIRE

    Cinthya Campos Salazar; Luis Solano Mora

    2001-01-01

    El propósito de este estudio fue determinar el efecto de un programa combinado de hidroquinesia y acondicionamiento físico y otro de acondicionamiento físico solamente en la movilidad articular en las caderas de un grupo de adultas mayores. Sesenta y tres sujetos (edad promedio = 66.06 años, S.D. ±6.77) fueron asignados a los grupos control, hidroterapia y acondicionamiento físico y solo acondicionamiento físico. La duración del programa fue de una hora por sesión, dos veces a la semana duran...

  7. Renovación de los equipos de producción de calor en un hotel : apoyo con energía solar

    OpenAIRE

    Fernández Fernández, Carlos

    2011-01-01

    El conjunto del presente documento dotará a todo el inmueble de las infraestructuras necesarias para la instalación del sistema de energía solar térmica. Asimismo, los condicionantes que mueven con especial cuidado el objeto de este proyecto son: - Elaborar un documento con carácter didáctico incorporando fundamentos de tecnología solar térmica y una memoria descriptiva en la que se detalle los distintos procedimientos de cálculo para la obtención de la cobertura solar para su posterior compa...

  8. Nursing Care and Patient Safety: Visualizing Medication Organization, Storage and Distribution with Photographic Research Methods Cuidado de enfermería y seguridad del paciente: visualizando la organización, acondicionamiento y distribución de medicamentos con método de investigación fotográfica Cuidados de enfermagem e segurança do paciente: visualizando a organização, acondicionamento e distribuição de medicamentos com método de pesquisa fotográfica

    Directory of Open Access Journals (Sweden)

    Anna Carolina Raduenz

    2010-12-01

    Full Text Available In this qualitative study, we adapted photographic research methods from earlier nursing research to identify factors related to organization, storage and distribution that could lead to errors in the selection, preparation and administration of medications. The research excerpt presented here was developed in a clinical unit of an urban Brazilian public hospital. The research participants were nurses working at that unit and students from the two final semesters of the Undergraduate Nursing Course. We collected digital photographs of the medication system and subsequently used photo elicitation to review the images with research participants, so as to obtain their perceptions and narratives of working with medications in the unit. We report selected findings here on the organization, storage and distribution of medications, which indicate there is room to improve the safety of the medication system.En este estudio cualitativo, se adoptó el método de investigación fotográfica de estudios anteriores, para identificar factores relacionados a la organización, acondicionamiento y distribución, los que podrían conducir a errores en la selección, preparación y administración de medicamentos. Esta parte de la investigación que se presenta fue desarrollada en una unidad de clínica médica de un Hospital Público, en Brasil. Los participantes de la investigación fueron enfermeros que trabajaban en aquella unidad y estudiantes de los dos últimos semestres del Curso de Graduación en Enfermería. Fueron obtenidas fotografías digitales del sistema de medicación y subsecuentemente, se obtuvieron las fotos para analizar las imágenes con los participantes de la investigación, a fin de obtener sus percepciones y narrativas al respecto del trabajo con medicamentos en aquella unidad. Se presenta una selección de los principales hallazgos de la investigación sobre organización, acondicionamiento y distribución de medicamentos, indicando que

  9. Acondicionamiento de reproductores y caracterización gonadal de Tawera gayi (Hupé, 1854 (Bivalva: Veneridae bajo condiciones controladas de cultivo.

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    P.Trigo

    2013-12-01

    Full Text Available El presente estudio describe el acondicionamiento de reproductores bajo sistema controlado del bivalvo Tawera gayi (Hupé, 1854, en el cual se caracterizó el estado de madurez gonadal en base a la presencia de células germinales masculinas y femeninas, estableciéndose su identificación mediante histología a través de microscopia óptica. Como metodología para el acondicionamiento se empleó una bandeja de 15,31 L de volumen útil donde fueron mantenidos 100 ejemplares de T. gayi. El sistema se mantuvo con agua de mar a 29-30 ppm con recambio de agua cada 3 días a temperatura promedio de 16 -18 °C. Con alimentación continua de una mezcla de microalgas de Isochrysis galbana y Chaetoceros muelleri. Los resultados obtenidos, ponen en manifiesto que T. gayi es una especie dioica, sin dimorfismo sexual. Presenta fecundación externa, con un ciclo reproductivo continuo, asincrónico y sin reposo gonadal. Durante las primeras semanas de aclimatación los machos presentaron 100 % de madurez máxima, mientras que las hembras demostraron un 71 % de madurez avanzada y 29% de madurez máxima. Una vez acondicionadas y con alimento continuo, se logró 100% de evacuación parcial en hembras y 50% de evacuación parcial y total en machos, obteniendo desove en cautiverio.

  10. Simulación y Análisis de la Operación de Sistemas de Acondicionamiento de Aire por Adsorción Analysis and Simulation of the Operation of an Adsorption Air Conditioning System

    Directory of Open Access Journals (Sweden)

    D. Builes

    2004-01-01

    Full Text Available En este trabajo se efectúa un análisis termodinámico de la operación de un sistema de acondicionamiento de aire, basado en el uso de una rueda deshumidificadora, una rueda de calor, un calentador de aire y humidificadores adiabáticos. El análisis se basó en un modelo macroscópico de balances de materia y energía, teniendo en cuenta las relaciones de equilibrio de adsorción aplicadas a la sorción de vapor de agua en sílica gel. El modelo permitió simular las condiciones de operación, y determinar la variación del coeficiente de desempeño, con respecto al incremento de temperatura requerido en el calentador de aire para la regeneración del desecante. Se determinó que el coeficiente de desempeño disminuye cuando la temperatura para la regeneración aumenta. Además, es posible obtener las condiciones de confort tan sólo variando la velocidad angular de la rueda, y la alimentación de agua en un humidificador, manteniendo un fácil control del sistemaIn this study a thermodynamic analysis is made of the operation of an air conditioning system based on the use of a dehumidifying wheel, a heat wheel, an air heater, and adiabatic humidifiers. The analysis was based on a macroscopic model of material and energy balances, taking into account the adsorption equilibrium relationships applied to the sorption of water vapor in silica gel. The model allowed to simulate the operating conditions and to determine the variation of the coefficient of performance with regard to the required temperature increment in the air heater for desiccant regeneration. It was determined that the coefficient of performance decreases when regeneration temperature increases. Furthermore, it is possible to obtain comfort conditions by varying only the angular speed of the wheel and the water feed to a humidifier, thus maintaining easy control of the system

  11. Transmisión de Calor y Materia con Reducción de Volumen Durante el Secado de Ladrillos de Cerámica Heat and Mass Transfer with Shrinkage During the Drying of Ceramic Bricks

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    José J. S Nascimento

    2006-01-01

    Full Text Available Se presenta un modelo matemático tridimensional transitorio aplicado al fenómeno de difusión de calor y materia con reducción de volumen en el interior de sólidos paralelepípedos. El modelo se ha aplicado al proceso de secado de ladrillos cerámicos. Se usó el método de los volúmenes finitos considerando propiedades térmicas y mecánicas constantes y una condición de contorno convectiva en la superficie del material. El modelo fue utilizado para estudiar el proceso de secado de un ladrillo de cerámica a temperaturas de 60 y 80ºC y en con humedades relativas del aire de 10,07 y 4,66%. Los resultados numéricos de contenido de humedad, temperatura y reducción de volumen, fueron comparados con datos experimentales para determinar los coeficientes de transporte. Se pudo concluir que: el fenómeno de reducción de volumen tiene dos periodos y afecta considerablemente la velocidad de secado del sólido, así como la distribución del contenido de humedad en el interior del mismo.A three-dimensional, transitional mathematical model is presented, as applied to the phenomenon of diffusion of heat and material which results in the reduction of volume in the interiors of parallelepiped solids. The model has been applied to the drying process of ceramic bricks. The method of finite volumes was employed, considering constant thermal and mechanical properties and surrounding convective conditions over the surface of the material. The model was used to study the process of drying of a ceramic brick at temperatures of 60° and 80°C with relative humidities of surrounding air of 10.07 and 4.66% . The numerical results of moisture content, temperature, and reduction in volume were compared with experimental data to determine the transport coefficients. It can be concluded that the phenomenon of reduction in volume occurs over two periods and considerably affects the drying of the solid, as well as the distribution of the moisture content within the

  12. Oleoyl-estrone metabolic effects in relation with caloric restriction in inbred Beta rats with spontaneous obesity and type 2 diabetes Efectos metabólicos de la oleoil-estrona en relación con la restricción calórica en ratas Beta endocriadas, con obesidad espontánea y diabetes tipo II

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    Marta D. Posadas

    2004-08-01

    Full Text Available Spontaneously hypertriacylglycerolemic obese and diabetic inbred IIM Beta rats were treated with oleoyl- estrone for 10 days. Pair-feeding was performed to determine some oleoyl-estrone effects dependent on the caloric restriction it promotes. Twenty-five 200 day-old Beta males receiving a daily gavage of 0.2 ml sunflower oil were divided into the following groups: 1 daily dose of 10 nmol/g oleoyl-estrone; 2 pair-fed; 3 control. The variables measured were: whole body protein, water and lipid; retroperitoneal and epididymal fat depot weights; plasma urea, glucose, insulin, triacylglycerols and cholesterol. Biomass and food intake were assessed daily. Oleoyl-estrone and pair-fed groups expressed similar variations in body composition and significant body weight losses due to reduction in food intake. Oleoyl-estrone and pair-fed treatments significantly reduced retroperitoneal fat depot weights, but not epididymal ones. In oleoyl-estrone and pair-fed groups hyperglycemia decreased and insulinemia lowered significantly. Plasma normal total cholesterolemia and hypertriacylglycerolemia values typical of Beta rats decreased strongly compared to controls, though attaining significantly different values between oleoyl-estrone and pair-fed groups. Plasma total cholesterol appeared as more sensitive to caloric restriction than triacylglycerols through a specific oleoyl-estrone- mediated effect.Ratas endocriadas de la línea IIMBeta con obesidad, hipertriacilglicerolemia y diabetes espontáneas fueron tratadas con oleoil-estrona durante 10 días. Un grupo con restricción alimentaria fue incluido en el estudio a fin de aislar algunos efectos de la oleoil-estrona dependientes de la restricción calórica que ésta promueve. Veinticinco ratas Beta macho de 200 días de edad a los que se suministró 0.2 ml de aceite de girasol por día se dividieron en los siguientes grupos: (1 dosis diaria de 10 nmol/g de oleoil-estrona; (2 restringido; (3 control. Las

  13. El comportamiento del hueco de ventana en la arquitectura vernácula mediterránea española ante las necesidades de acondicionamiento solar

    Directory of Open Access Journals (Sweden)

    Larrumbide, E.

    2015-09-01

    Full Text Available The window opening is one of the most important elements of the thermal envelope of a building passive conditioning, and therefore more sensitive to heat exchange with the outside and variations in sunlight conditions that manifest in the environment. Vernacular architecture, with a broad representation of types in the Iberian Peninsula, becomes the appropriate framework of analysis of the interrelationship between the building and the environment, and in particular between the window opening and the irradiation of the place. Developing a methodology to facilitate the study of the window opening from the point of view of sunlight, can get answers on the degree of adaptation featuring the same solar conditioning needs that are required in each climate zone.El hueco de ventana es uno de los elementos de acondicionamiento pasivo más importante de la envolvente térmica de una construcción, y por tanto el más sensible al intercambio térmico con el exterior y a las variaciones en las condiciones de soleamiento que se manifiesten en el entorno. La arquitectura vernácula, que cuenta con una amplia representación de tipos en la Península Ibérica, se convierte en el marco adecuado del análisis de la interrelación existente entre la edificación y el entorno, y en concreto entre el hueco de ventana y el soleamiento del lugar. El desarrollo de una metodología que facilite el estudio del hueco de ventana, desde el punto de vista del soleamiento, permite obtener respuestas sobre la mayor o menor adaptación que ofrece el mismo a las necesidades de acondicionamiento solar que se requieran en cada zona climática.

  14. Indicadores Antropométricos en un Centro de Acondicionamiento Físico Urbano de la Provincia de Heredia

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    Gustavo Rivera Cabezas

    2014-08-01

    Full Text Available El propósito de este estudio fue identificar los valores antropométricos y su relación con la salud en los usuarios del Centro de Acondicionamiento Físico (CAF de la Escuela de Ciencias de la Salud y Calidad de Vida (CIEMHCAVI de la Universidad Nacional. Se analizó 1000 expedientes, aunque por razones de ausencia de datos se trabajó con 563. La información recopilada correspondió a 315 hombres y 248 mujeres con edad promedio de 28,5 ± 11,3 y de 30,2 ± 11,3 años, respectivamente. Cada expediente contenía información sobre los valores antropométricos índice de masa corporal (IMC, peso, porcentaje de grasa, circunferencia de cintura y cadera. Los resultados relativos al porcentaje de grasa corporal e IMC correspondieron a una población sana según parámetros internacionales. Tanto hombres como mujeres mostraron IMC similares, aunque las mujeres evidenciaron valores promedio significativamente superiores a los hombres en cuanto al porcentaje de grasa y riesgo cardiovascular. Asimismo, se registró correlaciones positivas y significativas entre IMC, porcentaje de grasa y relación cintura cadera. En general, los datos analizados evidenciaron valores antropométricos saludables para la mayoría de la población que asistió al CAF de la CIEMHCAVI en el periodo comprendido entre el 2004 – 2006.

  15. Mejora del valor proteico para rumiantes de la harina de girasol mediante tratamientos combinados con ácidos (málico y fosfórico) y calor = Improvement of the protein value for ruminants of sunflower meal by combined treatments with acids (malic and orthophosphoric) and heat

    OpenAIRE

    Arroyo Martínez, José María

    2012-01-01

    El objetivo principal de esta tesis fue incrementar el valor proteico para rumiantes de la harina de girasol mediante tratamientos combinados con ácidos y calor para proteger sus proteínas frente a la degradación ruminal. Estos estudios comprenden dos experimentos realizados sobre ovinos mediante tecnologías in vitro (experimento 1) o in situ e in vivo (experimento 2), empleando siempre dos ácidos: málico u ortofosfórico. Aprovechando este último experimento, también se consideraron otros obj...

  16. Energy saving in hotels by means of heat pumps application; Ahorro de energia en hoteles mediante la aplicacion de bombas de calor

    Energy Technology Data Exchange (ETDEWEB)

    Romero Paredes R, Hernando; Ambriz G, Juan Jose [Universidad Autonoma Metropolitana, Unidad Iztapalapa (Mexico)

    2005-07-15

    The thermal energy is presented as an alternate saving technology for utilities by means of the acute implementation of heat pumps. The objective is to demonstrate the technical and economical feasibility of the application of commercial heat pumps to installations where the handling of opposite temperatures for the conditioning of a space and/or of a fluid is required. In this article it is described the functioning of a heat pump, its different operation principles or types as well as the large diversity of applications they can have in industry, utilities and residential buildings. As an application example the substitution of an electric boiler by a heat pump is presented in a hotel installation and its differences in performance regarding the environmental conditioning of a nearby area and the heating of swimming pool water are analyzed. [Spanish] Se presenta la energia termica como una tecnologia de ahorro alterna para empresas de servicios valiendose de la implementacion agudizada de bombas de calor. El objetivo es demostrar la factibilidad tecnica y economica de la aplicacion de bombas de calor comerciales a instalaciones donde se requiere la manipulacion de temperaturas opuestas para el acondicionamiento de un espacio y/o un fluido. Se describe el funcionamiento de una bomba de calor, sus diferentes principios de operacion o tipos, asi como la gran diversidad de aplicaciones que pueden tener en la industria, empresas de servicios y edificios residenciales. Como ejemplo de aplicacion se presenta la sustitucion de una caldera electrica por una bomba de calor en una instalacion hotelera y sus diferencias de rendimiento en el calentamiento de agua de alberca y el acondicionamiento ambiental de un area cercana.

  17. Las obras de acondicionamiento del Salto del Mont-Cenis

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    Vié, Georges

    1969-06-01

    Full Text Available The new dam at Mont Cenis has increased to water volume in the reservoir from 32 to 320 million m3 and provides a potential energy of 650.000 million Mp x m. This article describes the work involved in the construction of this project. Among other features, the water has been led to the reservoir along a network of varying cross-section, and of 28 km total length. The pressure conduit has been designed for a flow rate of 51 m3/s, its diameter varying between 4 and 5 m. The new power stations at Villarodin are fed by a pipe 3.6 km in length and 3 m in diameter. This conduit runs along a trench and is isolated from the ground, because of the gypsum and anhydrites contained in the soil. Its weight is 10.000 Mp, which is a European record. The power station comprises to vertical Pelton turbines of 195 MVA each, and a yearly output of 485 kWh.La capacidad de la nueva presa del Mont-Cenis ha aumentado con estas obras desde 32 hasta 320 millones de m3, permitiendo el abastecimiento de una energía potencial de 650.000 millones de Mp x m. En el artículo se describen las obras y operaciones necesarias para ello; entre otras, que las aguas captadas han sido llevadas al embalse por una red de galerías de sección variable de 28 km de longitud; y que la conducción forzada, de 18 km de longitud, fue dimensionada para un caudal de 51 m3/s, con un diámetro comprendido entre 4 y 5 metros. Las nuevas centrales de Villarodin están alimentadas por una desviación de 3,6 km de longitud y 3 m de diámetro. Este conducto, colocado en un foso inclinado para aislarlo del ter reno, en esa zona de yesos y anhidritas, principalmente, tiene un peso de 10.000 Mp, lo que constituye un récord europeo. La Central comprende dos grupos verticales de turbinas Pelton de 195 MVA cada uno, con una productividad de 485 millones de kWh.

  18. Determination of heat losses in the Cerro Prieto, Baja California, geothermal field steam transportation network based on the thermal insulation condition of the steam pipelines; Determinacion de perdidas de calor en la red de transporte de vapor del campo geotermico de Cerro Prieto, Baja California, con base en el estado fisico del aislamiento termico de vaporductos

    Energy Technology Data Exchange (ETDEWEB)

    Ovando Castelar, Rosember; Garcia Gutierrez, Alfonso; Martinez Estrella, Juan Ignacio [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: rovando@iie.org.mx; Canchola Felix, Ismael; Jacobo Galvan, Paul; Miranda Herrera, Carlos; Mora Perez, Othon [Comision Federal de Electricidad, Gerencia de Proyectos Geotermoelectricos, Residencia General de Cerro Prieto, Mexicali, B.C. (Mexico)

    2011-07-15

    In Cerro Prieto Geothermal Field (CPGF), the steam from producing wells is transported to power plants through a large and complex system of pipes thermally insulated with a 2 inches thick mineral wool or a fiber glass layer and an external aluminum or iron cover. The insulation material has been exposed to weather conditions during the field operation and has suffered density and thickness changes. In some cases the insulation has been lost completely, increasing heat transfer from the pipes to the environment. This paper analyzes the impact of the conditions of thermal insulation on heat losses in the CPGF steam-pipeline network. The heat losses are calculated by applying an iterative method to determine the surface temperature based on a heat balance calculated from the three basic mechanisms of heat transfer: conduction, convection, and radiation. Finally, using length and diameter data corresponding to the condition of the thermal insulation of each pipeline-and field operation data, the overall heat losses are quantified for steam lines throughout the pipeline network in the field. The results allow us to evaluate the magnitude of the heat losses in comparison with the overall energy losses occurring during steam transport from wells to the power plants. [Spanish] En el Campo Geotermico de Cerro Prieto (CGCP), BC, el transporte de vapor desde los pozos hasta las plantas generadoras de electricidad se lleva a cabo mediante un extenso y complejo sistema de tuberias que tipicamente se encuentran aisladas termicamente con una capa de 2 pulgadas de material aislante a base de lana mineral o fibra de vidrio, y una proteccion mecanica de aluminio o hierro galvanizado. Debido a la exposicion a las condiciones meteorologicas a traves del tiempo de operacion del campo, el aislamiento ha experimentado cambios en su densidad y espesor y en ocasiones se ha perdido por completo, lo cual repercute en una mayor transferencia de calor de las tuberias hacia el medio ambiente

  19. Calor de respiración de frutas y vegetales

    OpenAIRE

    Orrego Alzate, Carlos Eduardo

    2001-01-01

    El enfriamiento y la refrigeración de frutas y vegetales recién cosechados se complica debido a la generación de calor de estos materiales originada en su actividad respiratoria. El artículo que se presenta ilustra dos sistemas de cálculo para estimar el calor de respiración con propósitos de diseño de sistemas de almacenamiento refrigerado y reúne abundante información experimental sobre este tema, tomada de diversas fuentes bibliográficas, incluyendo datos sobre especies tropicales / ...

  20. Heat pumping using the thermal earth gradient to produce air conditioned and hot water with savings of up to 70%; Bombeo de calor utilizando el gradiente termico de la tierra para producir aire acondicionado y agua caliente con ahorros de hasta un 70%

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez Ramirez, Alejandro [Novaenergia de Mexico S.A. de C.V. (Mexico)

    2003-07-01

    The pumping of heat using the Earth heat as partial energy source bases its principle on which the energy of the ground is constant and the energy efficiency to produce air conditioning and hot water simultaneously is important, obtaining savings up to 70%, comparing itself with the traditional equipment and what these operate of separated way to produce each one of them the cold air and the hot water. The use of this technology presents an opportunity to reduce the energy costs of and the demand of the company. [Spanish] El bombeo de calor utilizando el calor de la tierra como fuente parcial de energia basa su principio en que la energia del suelo es constante y el rendimiento energetico para producir simultaneamente aire acondicionado y agua caliente es importante, obteniendose ahorros hasta de un 70%, comparandose con los equipos tradicionales y que estos operan de manera separada para producir cada uno de ellos el aire frio y el agua caliente. El uso de esta tecnologia presenta una oportunidad para reducir los costos de energia y demanda de la empresa.

  1. Nutritional intervention improves the caloric and proteic ingestion of head and neck cancer patients under radiotherapy La intervención nutricional mejora la ingestión calórica y proteica de los pacientes con cáncer de cabeza y cuello sometidos a radioterapia

    Directory of Open Access Journals (Sweden)

    M.ª C. Gonçalves Dias

    2005-10-01

    Full Text Available Malnutrition is commonly associated with head and neck cancer, due especially to anorexia, which is aggravated by radiotherapy. The objective of this study was to evaluate modifications to nutritional ingestion following three types of nutritional intervention. Sixty-four male out-patients (62.1 ± 1.5 years were divided into three groups: oral group, (n = 32 that received an adapted oral diet; feeding tube group, (n = 16 under home enteral nutrition via a nasoenteral feeding tube (6x/day; and supplement group, (n = 16 with oral diet associated to oral alimentary supplement between meals (3x/day. The groups were homogeneous and counseled to maintain a caloric ingestion of 40 kcal/kg. The diet for the oral group was adapted to the age and to the side effects of radiotherapyThe nutritional state of the three groups was evaluated for the caloric-proteic ingestion, anthropometric indicators (body weight, body mass index, triceps skinfold thickness, midarm muscle area, laboratorial indicators (total proteins, albumin, hematocrit, hemoglobin and total lymphocytes count, The results showed that all of the groups presented an increase in the ingestion of calories and proteins (p La malnutrición se asocia habitualmente con el cáncer de cabeza y cuello, especialmente debida a la anorexia, que se agrava por la radioterapia. El objetivo de este estudio fue evaluar las modificaciones de la ingestión nutricional tras tres tipos de intervención nutricional. Se dividió a 64 pacientes varones (62,1 ± 1,5 años en tres grupos: el grupo oral (n = 32, que recibió una dieta oral adaptada; el grupo con sonda de alimentación (n = 16, con nutrición enteral domiciliaria a través de una sonda nasoentérica de alimentación (6 veces/día; y el grupo con suplemento (n = 16 con dieta oral asociada a un suplemento alimenticio oral entre las comidas (3 veces/día. Los grupos eran homogéneos y orientados para mantener una ingestión calórica de 40 kcal/kg. La dieta

  2. Diseño, construcción y evaluación de un equipo tipo baúl para desinfección de sustratos agrícolas con calor Desing, construction and evaluation of trunk type equipment for agriculture sustrate disinfection with heat

    Directory of Open Access Journals (Sweden)

    Noel Chávez-Aguilera

    Full Text Available El objetivo de este estudio fue diseñar, construir y evaluar un equipo tipo baúl para desinfección en estático de sustratos agrícolas mediante aplicación de calor, a través de aire caliente y con vapor de agua aireado. La investigación se realizó en 2005 en los talleres y laboratorios de la Universidad Autónoma Chapingo, Texcoco, Estado de México, México. El diseño experimenetal utilizado fue factorial 2*2*3, el primer factor fue la fuente y medio de transferencia de calor: 1 resistencia eléctrica y aire caliente; y 2 combustión de diesel y vapor de agua aireado; el segundo, contenido de humedad del sustrato: 75 y 61%; el tercer factor fue tiempo de desinfección: 15, 30 y 45 min. Las variables respuesta fueron: tiempo para alcanzar la temperatura mínima deseada, rango de temperatura durante la desinfección, eficiencia de desinfección de Fusarium oxisporum culmorum y costo específico de energía. La desinfección con aire caliente mostró los mayores valores en tiempo para alcanzar la temperatura mínima deseada, rango de temperatura, eficiencia de desinfección y costo especifico de energía, en comparación con vapor de agua aireado.The objective of this study was the design, construction and evaluation of equipment for in static disinfection of agricultural substrates by applying heat from hot air and aerated steam sources. The research was conducted in 2005 at the workshops and laboratories of the Universidad Autonoma Chapingo, Texcoco, State of Mexico, Mexico. A factorial 2*2*3 experimental design was utilized, the first factor was the source and means of heat transfer: 1 electrical resistance and hot air and 2 combustion of diesel and aerated steam, the second factor was substrate moisture content:75 and 61% and disinfection time: 15, 30 and 45 min. The studied variables were: time to reach the desired temperature, temperature range during disinfection, disinfection efficiency of Fusarium oxisporum culmorum, specific

  3. Leucemia mieloblástica aguda tras un trasplante de progenitores hematopoyéticos en pacientes con leucemia aguda mieloblástica: características citogenéticas y moleculares

    OpenAIRE

    Grau Cat, Javier

    2016-01-01

    Las LAM que acontecen tras un TPH efectuado a pacientes con LAM siempre han sido consideradas recaídas de la LAM inicial. Sin embargo, estos pacientes han recibido tratamientos con regímenes que incluyen antraciclinas y citarabina y, posteriormente, se han consolidado con un TPH, previo acondicionamiento con agentes alquilantes, antimetabolitos e ICT. Dado que la quimioterapia previa recibida, principalmente la dosis total acumulada de agentes alquilantes, se considera el factor de riesgo más...

  4. The caloric cost of pregnancy.

    Science.gov (United States)

    1973-06-01

    To determine the amount of extra calories a pregnant woman needs to ensure normal growth of her fetus, a study was conducted using 11 normal women who were willing to spend 1 week in the hospital during the last half of pregnancy. The women were given a constant diet of known composition which closely approximated their normal diet at home. Data on fasting weight and fluid balance, nitrogen excretion (from urine samples), 24-hour oxygen consumption and CO2 production were recorded daily. The diet consisted of 80 gm. or more of high-quality protein and supplementary vitamins and iron. 7 women were in positive caloric balance eating 1600 to 2000 Kcal/day; their mean weight gain was 6.8 kg. The other 4, who were obese or who were prone to obesity, were on a lower caloric intake of 1200 to 1600 Kcal/day; despite this, their average gestational weight gain was 10.0 kg. All babies, except for 1 (the mother had placental insufficiency due to low implantation, premature separation, and antepartum hemorrhage; her baby weighed 2.58 kg. at 38 weeks), were born at term with a birthweight of more than 3 kg. The authors concluded that pregnancy hardly imposes any increase in physical activity on the women, and whatever physical effort is exerted is offset by a reduction in physical activity. A pregnant woman requires approximately 600 Kcal. daily for her activities; this amounts to total caloric requirements of 2100, 2200 and 2300 Kcal/day in each of the 3 trimesters. 12 oz. of homogenized milk per day is adequate to meet the extra caloric requirements of a well-nourished woman during her pregnancy. The findings suggest that a normal woman need not overeat to ensure normal growth of her fetus. PMID:4581116

  5. Bioclimatic conditioning places for propagation the plants; Acondicionamiento Bioclimatico de locales para programacion de plantas

    Energy Technology Data Exchange (ETDEWEB)

    Iriarte, Adolfo [Catamarca, (Argentina); Lesino, Gabriela [Buenos Aires, (Argentina); Matias, Cesar [Catamarca, (Argentina)

    2000-07-01

    A special tax reduction to promote agricultural investments in the Province of Catamarca in Argentina has created a strong demand of high quality plants of olive (Olea europea L.), walnut (Junglans regia L.) and fig (Ficus carica L.) trees. The method used for plant propagation consists of three stages: rooting of stem cuttings (two months), growth under controlled conditions in a greenhouse (four to five months) and rustication and acclimatization to outdoor conditions in a half-shadow protected area (three to four months). The plant is ready to be transferred to the field in nine to ten months. The rooting stage cannot take place outdoors in hot, arid and windy climates. This paper refers to the design, construction and monitoring of a building where the ambient temperature, humidity and illumination levels are controlled to promote the growth of roots, maintain the stem hydrated and allow restrained photosynthetic activity. Excellent thermal and agronomic results were obtained with rooting efficiencies of 43 to 75 % in summer and 30 to 60 % in winter for olive stems. [Spanish] La necesidad de produccion de olivo (Olea europea L.), nogal (Junglans regia L.) e higueras (Ficus carica L.) de alta calidad para satisfacer la demanda de los establecimientos agropecuarios, ha obligado a utilizar para la produccion de plantas la tecnica de enraizamiento de estacas semilenosas, lo que permite obtener plantas identicas a la planta madre. En regiones de climas calidos y ventosos los factores climaticos externos dificultan el control y mantenimiento de las condiciones ambientales dentro de los recintos destinados a la produccion de plantas mediante estacas. Esto exige disponer de una camara que permita controlar la temperatura y la humedad simultaneamente obtener niveles de iluminacion natural compatible con las necesidades fotosinteticas de las estacas. En el presente trabajo se describen los aspectos constructivos de una casa de vegetacion, analizandose el balance de calor

  6. Caloric beverage consumption patterns in Mexican children

    OpenAIRE

    Rivera Juan A; Hernández-Barrera Lucia; Bonvecchio Anabelle; Campirano Fabricio; Barquera Simon; Popkin Barry M

    2010-01-01

    Abstract Background Mexico has seen a very steep increase in child obesity level. Little is known about caloric beverage intake in this country as well as all other countries outside a few high income countries. This study examines overall patterns and trends in all caloric beverages from two nationally representative surveys from Mexico. Methods The two nationally representative dietary intake surveys (1999 and 2006) from Mexico are used to study caloric beverage intake in 17, 215 children. ...

  7. Efectos de la pérdida de peso mediante una dieta muy baja en calorías (VLCD sobre la pérdida de peso tras derivación biliopancreática en pacientes con obesidad severa

    Directory of Open Access Journals (Sweden)

    M. D. Ballesteros Pomar

    2013-02-01

    Full Text Available Introducción: Se ha comunicado recientemente que la reducción de peso previa a cirugía bariátrica mediante dieta muy baja en calorías (VLCD durante 2 semanas supone menor tasa de complicaciones postoperatorias. Es debatido, sin embargo, si la pérdida de peso preoperatoria con VLCD puede favorecer pérdida de peso postoperatoria. Objetivos: Valorar la eficacia de una VLCD, seguida durante 6 semanas preoperatorias, en el descenso de peso conseguido al año de la cirugía bariátrica. Evaluar los cambios en parámetros antropométricos y bioquímicos conseguidos con dicha dieta. Metodología: Estudio prospectivo no controlado en los pacientes obesos sometidos a derivación biliopancréatica en la Unidad de Obesidad de referencia en el periodo 2008-2010. Los pacientes recibieron durante 6 semanas previas a la intervención una VLCD que aportaba diariamente 840 kcal y 60 g de proteínas (Optisource®. Los datos descriptivos se presentan como media y desviación estándar (DS, y tras comprobar su distribución normal, fueron analizados mediante prueba t de Student, ANOVA o correlación de Pearson. Resultados: Fueron valorados 107 pacientes obesos, de 43,5 (10,2 años, el 72 % fueron mujeres con peso inicial 122,4 (18,6 Kg e IMC de 46,8 (5,5 kg/m². Un 24,5% perdieron más de 10 % de su peso inicial y un 73,5% más de 5% tras VLCD. La media de porcentaje pérdida de exceso de peso (% PSP a los 12 meses de la intervención fue 59,6 (13,4%, y aunque fue mayor en los pacientes que habían perdido peso con VLCD, no se asoció de forma significativa: aquellos pacientes con pérdida mayor de 5% perdieron a los 12 meses 59,5 (13,8% de PSP y 68,4 and 71 (16,2 % de exceso de IMC (%PEIMC, frente a 57,9 (13,1 % y 68,5 (16,6 % si no conseguían esa pérdida. El grupo de pacientes con pérdida mayor de 10 % consiguió %PSP de 63,3 (13,7 y %PEIMC de 70,9 (14,7 vs 58,2 (14,0 y 67,7 (16,7 si no perdieron >10% del peso inicial. No se encontró correlación entre

  8. Carnot to Clausius: Caloric to Entropy

    Science.gov (United States)

    Newburgh, Ronald

    2009-01-01

    This paper discusses how the Carnot engine led to the formulation of the second law of thermodynamics and entropy. The operation of the engine is analysed both in terms of heat as the caloric fluid and heat as a form of energy. A keystone of Carnot's thinking was the absolute conservation of caloric. Although the Carnot analysis was partly…

  9. Impairment of Caloric Function after Cochlear Implantation

    Science.gov (United States)

    Kuang, Heide; Haversat, Heather H.; Michaelides, Elias M.

    2015-01-01

    Purpose: This article seeks to review current literature on caloric function following cochlear implantation while analyzing any correlations of caloric function changes with vestibular symptoms. Method: This article is a systematic review of evidence-based literature. English language articles published between 1980 and 2014 that presented some…

  10. Colapso pelo calor esforço induzido: reconhecimento para salvar vidas e tratamento imediato em instalações atléticas Choque térmico relacionado con el ejercício: reconocimiento y tratamiento locales para salvar vidas Exertional heat stroke: life-saving recognition and onsite treatment in athletic settings

    Directory of Open Access Journals (Sweden)

    2005-12-01

    Full Text Available O prognóstico do colapso pelo calor esforço induzido depende do produto do tempo de duração em que a temperatura central ficou elevada e do grau da elevação. O atleta com EHS que tem pronta descoberta e que é resfriado de maneira eficiente, muito provavelmente irá sobreviver ao episódio com pouco ou nenhum efeito residual. Em contraste, o atleta com apresentação atrasada para o tratamento, especialmente se a área sob a curva de resfriamento for > 60 graus-minuto (centígrados terá um curso complicado e geralmente fatal. Os métodos de condução do resfriamento com imersão em gelo ou água gelada ou envolvimento em toalhas com água gelada proporcionarão uma rápida e consistente redução da temperatura de todo o corpo, que irá salvar tanto os órgãos quanto a vida. O reconhecimento depende em alto grau da suspeita por parte dos próprios atletas, treinadores e pessoal médico local. Em condições de alto risco, os atletas devem se supervisionar, procurando por mudanças sutis que podem ser sinais de EHS.El pronóstico del choque térmico (CT relacionado con el ejercicio depende del producto del periodo de tiempo en que la temperatura central se mantenga elevada y de la magnitud de esta elevación. El atleta con CT que sea diagnosticado y sea rápida y eficientemente refrescado probablemente sobrevivirá al episodio con ninguna o pocas complicaciones. Por otra parte aquel atleta que halla tenido un inicio tardío en el tratamiento con una área por debajo de la curva mayor de 60 grados-minuto (centigrados tendrá complicaciones y de seguro una evolución fatal. Los métodos de enfriamiento con hielo o inmersión en agua fría o toallas con agua helada en rotación permiten una reducción consistente y rápida de la temperatura corporal capaz de preservar los órganos y la vida. El reconocimiento depende del elevado grado de sospecha por parte de los atletas, técnicos y personal de apoyo médico. En condiciones de alto riesgo

  11. Caloric beverage consumption patterns in Mexican children

    Directory of Open Access Journals (Sweden)

    Rivera Juan A

    2010-10-01

    Full Text Available Abstract Background Mexico has seen a very steep increase in child obesity level. Little is known about caloric beverage intake in this country as well as all other countries outside a few high income countries. This study examines overall patterns and trends in all caloric beverages from two nationally representative surveys from Mexico. Methods The two nationally representative dietary intake surveys (1999 and 2006 from Mexico are used to study caloric beverage intake in 17, 215 children. The volume (ml and caloric energy (kcal contributed by all beverages consumed by the sample subjects were measured. Results are weighted to be nationally representative. Results The trends from the dietary intake surveys showed very large increases in caloric beverages among pre-school and school children. The contribution of whole milk and sugar-sweetened juices was an important finding. Mexican pre-school children consumed 27.8% of their energy from caloric beverages in 2006 and school children consumed 20.7% of their energy from caloric beverages during the same time. The three major categories of beverage intake are whole milk, fruit juice with various sugar and water combinations and carbonated and noncarbonated sugared-beverages. Conclusion The Mexican government, greatly concerned about obesity, has identified the large increase in caloric beverages from whole milk, juices and soft drinks as a key target and is initiating major changes to address this problem. They have already used the data to shift 20 million persons in their welfare and feeding programs from whole to 1.5% fat milk and in a year will shift to nonfat milk. They are using these data to revise school beverage policies and national regulations and taxation policies related to an array of less healthful caloric beverages.

  12. Evaluación del potencial reproductivo del chorito (Mytilus chilensis de dos poblaciones naturales sometidas a diferentes temperaturas de acondicionamiento Assessment of the reproductive potential of the mussel (Mytilus chilensis from two natural populations subjected to different conditioning temperatures

    Directory of Open Access Journals (Sweden)

    Luis Lagos

    2012-07-01

    Full Text Available Mytilus chilensis tiene ciclos reproductivos que varían latitudinalmente. Presenta reducida diferenciación genética y morfológica debido a un gran potencial de dispersión. Se acondicionaron reproductores de bahía Yaldad (Chiloé y bahía Zenteno (Punta Arenas a 9 ± 0,5°C y 15 ± 0,5°C, alimentados con dieta (1:1 de Isochrysis galbana y Chaetoceros neogracile. Se espera dilucidar si el acondicionamiento a diferentes temperaturas produce variaciones en el potencial reproductivo de las poblaciones. El menor desarrollo gonadal se produjo en los reproductores acondicionados a 9°C, mientras que el mayor se produjo en los reproductores acondicionados a 15°C provenientes de Chiloé. La fecundidad de los reproductores de Yaldad fue mayor que los de Zenteno. El diámetro de los ovocitos fue mayor en los reproductores de Zenteno y en ambas poblaciones fue mayor a 9°C. Ni el porcentaje de huevos fecundados ni el porcentaje de eclosión de larvas D mostraron diferencias significativas entre las poblaciones a ninguna de las temperaturas de acondicionamiento. De acuerdo con estos resultados, no se logra establecer diferencias en el potencial reproductivo en las poblaciones y bajo las condiciones de este estudio.The reproductive cycles of Mytilus chilensis vary latitudinally. This species has reduced genetic and morphological differentiation due to its high potential for dispersal. Broodstocks from Yaldad Bay (Chiloé and Zenteno Bay (Punta Arenas were conditioned at 9 ± 0.5°C and 15 ± 0.5°C, and were fed a diet (1:1 of Isochrysis galbana and Chaetoceros neogracile. We expected to determine whether conditioning at different temperatures produces changes in the reproductive potential of the populations. Gonadal development was lowest in the broodstocks conditioned at 9°C, and highest in those conditioned at 15°C, from Chiloé. Fertility was greater in broodstocks from Yaldad than in those from Zenteno. Oocyte diameter was greater in broodstocks

  13. Análise da redistribuição de calor com agentes inalatórios, em ratos submetidos a laparotomia e pneumoperitônio, através da termografia infravermelha Análisis de la redistribución de calor con agentes inhalatorios, en ratones sometidos a laparotomia y pneumoperitonio, a través de termografia infraroja Analysis of heat loss using inhalation agents in rats subjected to laparotomy and increased intra-abdominal pressure, using digital infrared thermal image

    Directory of Open Access Journals (Sweden)

    Daniel Colman

    2002-06-01

    Full Text Available JUSTIFICATIVA E OBJETIVOS: A Anestesiologia envolve o manuseio de situações inerentes ao ato anestésico e operatório que cursam com o desequilíbrio da homeostase térmica do paciente, ocasionando efeitos fisiológicos deletérios. O presente estudo objetiva qualificar e quantificar os fenômenos de redistribuição térmica em ratos submetidos à anestesia inalatória, durante a indução, e em situações cirúrgicas de laparotomia e pneumoperitônio. MÉTODO: Foram utilizados 90 ratos, que foram submetidos à anestesia inalatória, distribuídos em três grupos, em que foram utilizados: halotano, isoflurano e sevoflurano. Em cada grupo houve divisão em outros três sub-grupos: I - controle, II - laparotomia mediana com exposição de alças intestinais; III - pneumoperitônio de 15 mmHg. A análise termodinâmica realizou-se de duas formas: através da temperatura central esofágica e da imagem digital térmica infravermelha. RESULTADOS: Não houve diferença significativa em relação aos anestésicos inalatórios entre os grupos I e II em relação a perda de calor. Em relação ao grupo III, houve diferença entre o isoflurano e o sevoflurano, sendo o isoflurano o anestésico responsável pela maior perda de temperatura no animal. CONCLUSÕES: O sevoflurano foi o agente anestésico inalatório que determinou menor perda de calor frente ao pneumoperitônio, em relação ao isoflurano e halotano.JUSTIFICATIVA Y OBJETIVOS: La Anestesiología envuelve el manoseo de situaciones inherentes al acto anestésico y operatorio que cursan con el desequilibrio de la homeóstasis térmica del paciente, ocasionando efectos fisiológicos deletéreos. El presente estudio objetiva calificar y cuantificar los fenómenos de redistribución térmica en ratones sometidos a anestesia inhalatoria, durante la inducción, y en situaciones quirúrgicas de laparotomia y pneumoperitonio. MÉTODO: Fueron utilizados 90 ratones, sometidos a anestesia inhalatoria

  14. Atomistic simulations of caloric effects in ferroelectrics

    Science.gov (United States)

    Lisenkov, Sergey; Ponomareva, Inna

    2013-03-01

    The materials that exhibit large caloric effects have emerged as promising candidates for solid-state refrigeration which is an energy-efficient and environmentally friendly alternative to the conventional refrigeration technology. However, despite recent ground breaking discoveries of giant caloric effects in some materials they appear to remain one of nature's rarities. Here we use atomistic simulations to study electrocaloric and elastocaloric effects in Ba0.5Sr0.5TiO3 and PbTiO3 ferroelectrics. Our study reveals the intrinsic features of such caloric effects in ferroelectrics and their potential to exhibit giant caloric effects. Some of the findings include the coexistence of negative and positive electrocaloric effects in one material and an unusual field-driven transition between them as well as the coexistence of multiple giant caloric effects in Ba0.5Sr0.5TiO3 alloys. These findings could potentially lead to new paradigms for cooling devices. This work is partially supported by the U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under award DE-SC0005245.

  15. Isla de calor en Toluca, México

    Directory of Open Access Journals (Sweden)

    Carlos Constantino Morales Méndez

    2007-01-01

    Full Text Available El clima de la ciudad de Toluca y del mundo ha sido modificado como consecuencia del crecimiento de su población y el aumento de las dimensiones de su distribución territorial. Las variaciones atmosféricas son más acusadas entre los espacios urbanos y rurales a medida que las ciudades son más grandes y su mancha urbana es más extensa,así como de la reducción de la vegetación, el aumento en la calefacción en casas y edificios y por la contaminación del aire. Para identificar los espacios con calor más intenso por la infraestructura urbana, se propone una metodología que consiste en la determinación de los valores de temperatura que se registraron en dos días típicos de invierno y verano, durante el día y la noche,mostrando la distribución de la isla de calor en la zona de estudio, a partir de los datos delas estaciones de la Red Automática de Monitoreo Ambiental (RAMA. Asimismo, se considera el comportamiento y variación de algunas variables atmosféricas como humedad relativa, precipitación y viento, para mostrar su comportamiento relativamente anómalo en la zona urbana.

  16. Coeficientes de transferencia de calor y pérdida de eficiencia en intercambiadores de calor de placas durante el enfriamiento del licor amoniacal

    Directory of Open Access Journals (Sweden)

    Enrique Torres-Tamayo

    2011-10-01

    Full Text Available En la planta de Recuperación de Amoniaco de la empresa niquelera Ernesto Che Guevara la pérdida de eficiencia del proceso de enfriamiento del licor amoniacal, mediante el uso de intercambiadores de calor de placas, se asocia a la incorrecta estimación de los coeficientes de transferencia de calor y la acumulación de incrustaciones en la superficie de intercambio; lo anterior incrementa el consumo de agua, la energía disponible en el sistema y los costos de mantenimiento. Se realizó una investigación en un intercambiador de calor de placas, con el objetivo de determinar los coeficientes de transferencia y la influencia de las incrustaciones en la pérdida de eficiencia de la instalación. Mediante un procedimiento iterativo se determinó la ecuación del número de Nusselt y su dependencia con el Reynolds y Prandtl, para ello se utilizó un diseño experimental multifactorial y mediciones de los parámetros de trabajo de la instalación en función del tiempo. Los resultados predicen el conocimiento de los coeficientes para el cálculo del número de Nusselt, con los valores de Reynolds y Prandtl, para ambos fluidos (licor amoniacal y agua. Los valores de los coeficientes del licor son inferiores, ello se debe a la presencia de componentes gaseosos. La comparación con resultados de otros autores muestra correspondencia con los de Thonon. Se recomienda la limpieza y mantenimiento de la instalación en un período de 27 días debido a la reducción de la eficiencia térmica hasta valores inferiores al 70 %.

  17. Calidad de vida relacionada con la salud en pacientes con trasplante de progenitores hematopoyéticos

    Directory of Open Access Journals (Sweden)

    Margarita Ruiz Seixas

    2014-12-01

    Full Text Available El Trasplante de Progenitores Hematopoyéticos (TPH es la primera opción de tratamiento en múltiples patologías. El análisis de la calidad de vida de estos pacientes es necesario para evaluar resultados y ofrecer información al paciente. Objetivo: Se analiza la evolución de la calidad de vida mediante estudio descriptivo longitudinal, en la Unidad Clínica de Hematología del Hospital Universitario Virgen del Rocío. Resultados: El análisis con SF36 rinde en las mediciones basal, 2 y 9 meses tras TPH, en escala física 43.5, 39.2 y 43.2 y en mental 48.7, 44.7 y 51.2. No se observaron diferencias por modalidad de trasplante (autólogo o alogénico o tipo de acondicionamiento. Conclusión: La calidad de vida inicial de los pacientes con TPH es inferior a la población estándar, empeorando a los dos meses y produciéndose mejoría en funcionamiento mental a los 9. No hay evidencias de que influya la modalidad de TPH o el acondicionamiento previo.

  18. Epigenetic regulation of caloric restriction in aging

    Directory of Open Access Journals (Sweden)

    Daniel Michael

    2011-08-01

    Full Text Available Abstract The molecular mechanisms of aging are the subject of much research and have facilitated potential interventions to delay aging and aging-related degenerative diseases in humans. The aging process is frequently affected by environmental factors, and caloric restriction is by far the most effective and established environmental manipulation for extending lifespan in various animal models. However, the precise mechanisms by which caloric restriction affects lifespan are still not clear. Epigenetic mechanisms have recently been recognized as major contributors to nutrition-related longevity and aging control. Two primary epigenetic codes, DNA methylation and histone modification, are believed to dynamically influence chromatin structure, resulting in expression changes of relevant genes. In this review, we assess the current advances in epigenetic regulation in response to caloric restriction and how this affects cellular senescence, aging and potential extension of a healthy lifespan in humans. Enhanced understanding of the important role of epigenetics in the control of the aging process through caloric restriction may lead to clinical advances in the prevention and therapy of human aging-associated diseases.

  19. Use of caloric and non-caloric sweeteners in US consumer packaged foods, 2005–9

    OpenAIRE

    Ng, Shu Wen; Slining, Meghan M.; Popkin, Barry M

    2012-01-01

    Our understanding of the use of caloric (CS) and non-caloric sweeteners (NCS) in the US food supply is limited. This study utilizes full ingredient list and nutrition facts panel (NFP) data from Gladson Nutrition Database, and nationally representative purchases of consumer packaged foods from Nielsen Homescan in 2005 through 2009 to understand the use of CS (including FJC) and NCS in CPG foods.

  20. CALIDAD DEL PALMITO EN FUNCIÓN DE LA FERTILIZACIÓN Y DEL ACONDICIONAMIENTO POSCOSECHA

    Directory of Open Access Journals (Sweden)

    Francisco Paulo Chaimsohn

    2009-01-01

    días. El palmito empacado en las bolsas plásticas a 5 °C se conservó en buenas condiciones hasta el final del almacenamiento. La bandeja de poliestireno cubierta con plástico fue inapropiada para la conservación del producto.

  1. Conservación por calor

    OpenAIRE

    Cobos García, Angel; Díaz Rubio, Olga

    2011-01-01

    Esta unidade didáctica denominada Conservación por calor forma parte da materia «Tecnoloxía do procesado de alimentos» que se impartirá no primeiro semestre do 2º curso do Grao en Nutrición Humana e Dietética. A materia estrutúrase en diferentes unidades didácticas, tratando cada unha delas as diferentes tecnoloxías de procesado dos alimentos, tanto de conservación coma de transformación. A presente unidade didáctica aborda a conservación dos alimentos por calor. Este método permite destruír ...

  2. The Effectiveness of four Motor Games for the Abdominal Conditioning Eficacia de cuatro juegos motores para el acondicionamiento de los músculos del abdomen

    Directory of Open Access Journals (Sweden)

    B. Flores

    2010-09-01

    la coactivación de los músculos del abdomen entre las diferentes tareas. Los juegos motores produjeron niveles de actividad eléctrica iguales o superiores a los obtenidos por el encorvamiento del tronco en los músculos OE y OI. La carretilla fue la tarea que generó las intensidades de contracción más elevadas en todos los músculos analizados. El encorvamiento del tronco activó principalmente los músculos RA y OI. Por el contrario, los juegos activaron con mayor intensidad los músculos oblicuos. Según estos resultados, los juegos referidos son tareas eficaces para el acondicionamiento de la musculatura abdominal.
    PALABRAS CLAVE: juegos motores, ejercicios, entrenamiento, músculos abdominales, electromiografía.

  3. Absorption heat pump integrated in an effluent purification system; Bomba de calor por absorcion integrada a un sistema de purificacion de efluentes

    Energy Technology Data Exchange (ETDEWEB)

    Santoyo, Socrates; Siqueiros, Javier; Heard, Christopher; Santoyo, Edgar [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1996-12-31

    The results derived of the integration of an absorption heat pump to an industrial effluents purification system, are presented. The advantages of these heat pumps with respect to heat pumps by mechanical compression of vapor, as well as the advantages in using absorption heat pumps in simple distillation systems, are mentioned. Finally, a description is made of the equipment designed and built, as well as the results obtained in a preliminary test. [Espanol] Se presentan los resultados derivados de la integracion de una bomba de calor por absorcion a un sistema de purificacion de efluentes industriales. Se mencionan las ventajas de este tipo de bombas de calor con respecto a las de calor por compresion mecanica de vapor, asi como las ventajas de usar bombas de calor en sistemas de destilacion simple. Finalmente, se describe el equipo disenado y construido, asi como los resultados obtenidos de una prueba preliminar.

  4. Use of non-caloric edulcorants in children

    Directory of Open Access Journals (Sweden)

    Calzada León Raúl

    2014-07-01

    Full Text Available We analyze the health normativity for the denomination of non caloric edulcorants in Mexico, and the authorization for the use of natural and synthetic non caloric edulcorants in newborn and until puberty. Special emphasis was given to the consecutive points of safety required in order to assure that they are free of secondary effects. For each non caloric edulcorant available in Mexico, we looked into the studies which mention their side effects in terms of growth and overall.

  5. "Land Productivity and Economic Development: Caloric Suitability vs. Agricultural Suitability"

    OpenAIRE

    Oded Galor; Omer Ozak

    2015-01-01

    This paper establishes that the Caloric Suitability Index (CSI) dominates the commonly used measure of agricultural suitability in the examination of the effect of land productivity on comparative economic development. The analysis demonstrates that the agricultural suitability index does not capture the large variation in the potential caloric yield across equally suitable land, reflecting the fact that land suitable for agriculture is not necessarily suitable for the most caloric-intensive ...

  6. Modeling microscale heat transfer using Calore.

    Energy Technology Data Exchange (ETDEWEB)

    Gallis, Michail A.; Rader, Daniel John; Wong, Chung-Nin Channy; Bainbridge, Bruce L.; Torczynski, John Robert; Piekos, Edward Stanley

    2005-09-01

    Modeling microscale heat transfer with the computational-heat-transfer code Calore is discussed. Microscale heat transfer problems differ from their macroscopic counterparts in that conductive heat transfer in both solid and gaseous materials may have important noncontinuum effects. In a solid material, three noncontinuum effects are considered: ballistic transport of phonons across a thin film, scattering of phonons from surface roughness at a gas-solid interface, and scattering of phonons from grain boundaries within the solid material. These processes are modeled for polycrystalline silicon, and the thermal-conductivity values predicted by these models are compared to experimental data. In a gaseous material, two noncontinuum effects are considered: ballistic transport of gas molecules across a thin gap and accommodation of gas molecules to solid conditions when reflecting from a solid surface. These processes are modeled for arbitrary gases by allowing the gas and solid temperatures across a gas-solid interface to differ: a finite heat transfer coefficient (contact conductance) is imposed at the gas-solid interface so that the temperature difference is proportional to the normal heat flux. In this approach, the behavior of gas in the bulk is not changed from behavior observed under macroscopic conditions. These models are implemented in Calore as user subroutines. The user subroutines reside within Sandia's Source Forge server, where they undergo version control and regression testing and are available to analysts needing these capabilities. A Calore simulation is presented that exercises these models for a heated microbeam separated from an ambient-temperature substrate by a thin gas-filled gap. Failure to use the noncontinuum heat transfer models for the solid and the gas causes the maximum temperature of the microbeam to be significantly underpredicted.

  7. A Dissociation Between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks.

    Science.gov (United States)

    Delogu, Franco; Huddas, Claire; Steven, Katelyn; Hachem, Souheila; Lodhia, Luv; Fernandez, Ryan; Logerstedt, Macee

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). Fifty-five college students rated 14 commercially available carbonated soft drinks in terms of sweetness and likeability. They were also asked to recognize, if the drinks contained sugar or a non-caloric artificial sweetener. Overall, participants showed poor accuracy in discriminating drinks' sweeteners, with significantly lower accuracy for SSBs than ASBs. Interestingly, we found a dissociation between sweetener recognition and drink pleasantness. In fact, in spite of a chance-level discrimination accuracy of SSBs, their taste was systematically preferred to the taste of non-caloric beverages. Our findings support the idea that hedonic value of carbonated soft drinks is dissociable from its identification and that the activation of the pleasure system seems not to require explicit recognition of the sweetener contained in the soft drink. We hypothesize that preference for carbonated soft drinks containing sugar over non-caloric alternatives might be modulated by metabolic factors that are independent from conscious and rational consumers' choices. PMID:26858681

  8. A Dissociation Between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    Science.gov (United States)

    Delogu, Franco; Huddas, Claire; Steven, Katelyn; Hachem, Souheila; Lodhia, Luv; Fernandez, Ryan; Logerstedt, Macee

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). Fifty-five college students rated 14 commercially available carbonated soft drinks in terms of sweetness and likeability. They were also asked to recognize, if the drinks contained sugar or a non-caloric artificial sweetener. Overall, participants showed poor accuracy in discriminating drinks’ sweeteners, with significantly lower accuracy for SSBs than ASBs. Interestingly, we found a dissociation between sweetener recognition and drink pleasantness. In fact, in spite of a chance-level discrimination accuracy of SSBs, their taste was systematically preferred to the taste of non-caloric beverages. Our findings support the idea that hedonic value of carbonated soft drinks is dissociable from its identification and that the activation of the pleasure system seems not to require explicit recognition of the sweetener contained in the soft drink. We hypothesize that preference for carbonated soft drinks containing sugar over non-caloric alternatives might be modulated by metabolic factors that are independent from conscious and rational consumers’ choices. PMID:26858681

  9. A Dissociation between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    Directory of Open Access Journals (Sweden)

    Franco eDelogu

    2016-01-01

    Full Text Available Consumption of sugar-sweetened beverages (SSBs is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs. 55 college students rated 14 commercially available carbonated soft drinks in terms of sweetness and likeability. They were also asked to recognize if the drinks contained sugar or a non-caloric artificial sweetener. Overall, participants showed poor accuracy in discriminating drinks’ sweeteners, with significantly lower accuracy for SSBs than ASBs. Interestingly, we found a dissociation between sweetener recognition and drink pleasantness. In fact, in spite of a chance-level discrimination accuracy of SSBs, their taste was systematically preferred to the taste of non-caloric beverages. Our findings support the idea that hedonic value of carbonated soft drinks is dissociable from its identification and that the activation of the pleasure system seems not to require explicit recognition of the sweetener contained in the soft drink. We hypothesize that preference for carbonated soft drinks containing sugar over non-caloric alternatives might be modulated by metabolic factors that are independent from conscious and rational consumers’ choices.

  10. Caloric versus low-caloric sweeteners: Can the body be fooled?

    NARCIS (Netherlands)

    Smeets, P.A.M.

    2010-01-01

    Low-caloric artificial sweeteners have been around for several decades now. Still, the debate over their usefulness in decreasing energy intake is ongoing. In principle, replacing sugar-containing foods with 'light' versions will lead to decreased energy intake. However, the reality of food intake b

  11. Transferencia de calor en el secado solar a la intemperie de menas lateríticas ferroniquelíferas

    Directory of Open Access Journals (Sweden)

    Yoalbys Retirado-Mediaceja

    2011-03-01

    Full Text Available En Moa, las menas lateríticas son sometidas a secado solar a la intemperie para reducirles el contenido de humedad antes de incorporarlas al proceso de secado térmico convencional. Este artículo evalúa los procesos de transferencia de calor fundamentales que tienen lugar durante el secado natural con el propósito de determinar el modo predominante de transferencia de calor. En dos pilas de menas lateríticas expuestas a secado solar natural se midieron las variables climatológicas y termodinámicas que influyen en la transferencia de calor por convección y radiación durante el secado y se calcularon, además, los criterios adimensionales para determinar el tipo predominante de convección. Se comprobó que durante el secado solar a la intemperie predomina la convección y que en las condiciones de experimentación analizadas la radiación tuvo una incidencia secundaria. Los resultados evidenciaron que el calor se transfiere por convección libre, forzada y mixta, predominando la forzada, para la cual los coeficientes de transferencia de calor mínimos y máximos mostraron pequeñas variaciones entre ambas pilas. Los flujos de calor por convección promedios fueron 978,74 y 1 156,58 W/m2 , mientras que los flujos por radiación ascendieron a 324,71 y 355,36 W/m2 para las pilas #1 y #2, respectivamente.

  12. Heat pump for purification of geothermal brines; Bomba de calor para purificacion de salmuera geotermica

    Energy Technology Data Exchange (ETDEWEB)

    Santoyo-Gutierrez, S; Barragan-Reyes, R.M; Holland, F.A [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: rmb@iie.org.mx

    2007-01-15

    Integrated use of geothermal resources is one of the most important goals for the future. Presently geothermal heat pumps offer two benefits: using heat from residual brines and converting these brines into very pure water. Designs and descriptions are presented of an experimental system to purify geothermal brines integrated to an adsorption heat-pump. The system was constructed and tested in the IIE (Institute for Electrical Research) facilities. During the experimental stage, pure water was obtained. Maximum capacity for pure water was 4.3 kg per hour, presenting an Actual Coefficient of Performance (COP)A of 1.4. The results are encouraging to project units at an industrial level for operating with geothermal and/or solar heat. [Spanish] El aprovechamiento integral de los recursos geotermicos en todas sus formas es una de las metas importantes a lograr en los proximos anos. Hoy en dia, el uso de las bombas de calor en la geotermia ofrece un doble beneficio: aprovechan el calor de los fluidos de desecho y tienen la capacidad de transformar la salmuera geotermica en agua de alta pureza. Se presenta el diseno y descripcion de un sistema experimental para purificacion de salmuera geotermica integrado a una bomba de calor por absorcion, el cual fue construido y probado en el Instituto de Investigaciones Electricas. En toda la etapa de experimentacion se obtuvo agua pura. La capacidad maxima alcanzada de produccion de agua pura de este sistema fue de 4.3 kg por hora, mostrando un rendimiento en terminos del Coeficiente Real de Rendimiento (COP)A de 1.4. Estos resultados se consideran alentadores para la proyeccion de unidades a escala industrial que puedan ser operadas con calor geotermico y/o solar.

  13. Efecto del calor aportado en recargues nanoestructurados base hierro

    Directory of Open Access Journals (Sweden)

    Agustín Gualco

    2013-12-01

    Full Text Available En los últimos años se han desarrollado consumibles de soldadura que depositan recubrimientos duros de aleaciones base hierro nanoestructuradas de gran resistencia al desgaste abrasivo. Las resistencias al desgaste erosivo y abrasivo están controladas principalmente por la composición química y la microestructura. A su vez, la microestructura del metal depositado puede presentar variaciones con el procedimiento de soldadura empleado, especialmente en relación al aporte térmico. Los parámetros operativos que definen el aporte térmico (tensión, corriente y velocidad de soldadura afectan aspectos como la geometría del cordón (ancho, penetración y sobremonta y la dilución con el material base. El propósito de este trabajo fue estudiar el efecto del calor aportado sobre las características geométricas del cordón, la dilución y la evolución microestructural de una aleación nanoestructurada base hierro, depositada por FCAW. Se soldaron muestras con aportes térmicos de entre 0,5 y 3,5 kJ/mm. Sobre cada cupón soldado se realizó un relevamiento dimensional, se analizó la composición química y se caracterizó la microestructura usando microscopías óptica y electrónica de barrido y difracción de rayos X. También se midieron la microdureza del depósito, el tamaño de cristalita y el grado de dilución. Se observó una gran influencia de las condiciones de proceso sobre la geometría del cordón. La dilución varió entre un 30 y un 40%, la microdureza del depósito se encontró entre 800 y 870 HV1 y el tamaño de cristalita osciló entre 105 y 130 nm, en función de las variables de proceso empleadas. Las mayores durezas y los menores tamaños de cristalita se obtuvieron con el menor aporte térmico, asociado a una menor dilución.

  14. Caloric Restriction Mimetics Enhance Anticancer Immunosurveillance.

    Science.gov (United States)

    Pietrocola, Federico; Pol, Jonathan; Vacchelli, Erika; Rao, Shuan; Enot, David P; Baracco, Elisa E; Levesque, Sarah; Castoldi, Francesca; Jacquelot, Nicolas; Yamazaki, Takahiro; Senovilla, Laura; Marino, Guillermo; Aranda, Fernando; Durand, Sylvère; Sica, Valentina; Chery, Alexis; Lachkar, Sylvie; Sigl, Verena; Bloy, Norma; Buque, Aitziber; Falzoni, Simonetta; Ryffel, Bernhard; Apetoh, Lionel; Di Virgilio, Francesco; Madeo, Frank; Maiuri, Maria Chiara; Zitvogel, Laurence; Levine, Beth; Penninger, Josef M; Kroemer, Guido

    2016-07-11

    Caloric restriction mimetics (CRMs) mimic the biochemical effects of nutrient deprivation by reducing lysine acetylation of cellular proteins, thus triggering autophagy. Treatment with the CRM hydroxycitrate, an inhibitor of ATP citrate lyase, induced the depletion of regulatory T cells (which dampen anticancer immunity) from autophagy-competent, but not autophagy-deficient, mutant KRAS-induced lung cancers in mice, thereby improving anticancer immunosurveillance and reducing tumor mass. Short-term fasting or treatment with several chemically unrelated autophagy-inducing CRMs, including hydroxycitrate and spermidine, improved the inhibition of tumor growth by chemotherapy in vivo. This effect was only observed for autophagy-competent tumors, depended on the presence of T lymphocytes, and was accompanied by the depletion of regulatory T cells from the tumor bed. PMID:27411589

  15. Caloric vestibular stimulation in aphasic syndrome

    Directory of Open Access Journals (Sweden)

    David eWilkinson

    2013-12-01

    Full Text Available Caloric vestibular stimulation (CVS is commonly used to diagnose brainstem disorder but its therapeutic application is much less established. Based on the finding that CVS increases blood flow to brain structures associated with language and communication, we assessed whether the procedure has potential to relieve symptoms of post-stroke aphasia. Three participants, each presenting with chronic, unilateral lesions to the left hemisphere, were administered daily CVS for 4 consecutive weeks. Relative to their pre-treatment baseline scores, two of the three participants showed significant improvement on both picture and responsive naming at immediate and one-week follow-up. One of these participants also showed improved sentence repetition, and another showed improved auditory word discrimination. No adverse reactions were reported. These data provide the first, albeit tentative, evidence that CVS may relieve expressive and receptive symptoms of aphasia. A larger, sham-controlled study is now needed to further assess efficacy.

  16. A Dissociation Between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    OpenAIRE

    Delogu, Franco; Huddas, Claire; Steven, Katelyn; Hachem, Souheila; Lodhia, Luv; Fernandez, Ryan; Logerstedt, Macee

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). Fifty-five college students rated 14 commercially available carbonated soft drinks in terms ...

  17. A Dissociation between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    OpenAIRE

    Franco eDelogu; Claire eHuddas; Katelyn eSteven; Souheila eHachem; Luv eLodhia; Ryan eFernandez; Macee eLogerstedt

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). 55 college students rated 14 commercially available carbonated soft drinks in terms of sweet...

  18. Normal Caloric Responses during Acute Phase of Vestibular Neuritis

    Science.gov (United States)

    Lee, Sun-Uk; Park, Seong-Ho; Kim, Hyo-Jung; Koo, Ja-Won

    2016-01-01

    Background and Purpose We report a novel finding of caloric conversion from normal responses into unilateral paresis during the acute phase of vestibular neuritis (VN). Methods We recruited 893 patients with a diagnosis of VN at Dizziness Clinic of Seoul National University Bundang Hospital from 2003 to 2014 after excluding 28 patients with isolated inferior divisional VN (n=14) and those without follow-up tests despite normal caloric responses initially (n=14). We retrospectively analyzed the neurotological findings in four (0.5%) of the patients who showed a conversion from initially normal caloric responses into unilateral paresis during the acute phase. Results In those four patients, the initial caloric tests were performed within 2 days of symptom onset, and conversion into unilateral caloric paresis was documented 1–4 days later. The clinical and laboratory findings during the initial evaluation were consistent with VN in all four patients except for normal findings in bedside head impulse tests in one of them. Conclusions Normal findings in caloric tests should be interpreted with caution during the acute phase of suspected VN. Follow-up evaluation should be considered when the findings of the initial caloric test are normal, but VN remains the most plausible diagnosis. PMID:26932259

  19. Unix version of CALOR89 for calorimeter applications

    International Nuclear Information System (INIS)

    CALOR89 is a system of coupled Monte Carlo particle transport computer codes which has been successfully employed for the estimation of calorimeter parameters in High Energy Physics. In the past CALOR89 has been running on various IBM machines and on CRAY X-MP at Lawrence Livermore Lab. These machines had non-unix operating systems. In this report we present a UNIX version of CALOR89, which is especially suited for the UNIX work stations. Moreover CALOR89 is also been supplemented with two new program packages which makes it more user friendly. CALPREP is a program for the preparation of the input files for CALOR89 in general geometry and ANALYZ is an analysis package to extract the final results from CALOR89 relevant to calorimeters. This report also provides two script files LCALOR and PCALOR. LCALOR runs CALOR89 sequences of programs and EGS4 for a given configuration sequentially on a single processor and PCALOR concurrently on a multiprocessor unix workstation

  20. Acondicionamiento de la delegación de Zaragoza del Colegio Oficial de Arquitectos de Aragón y La Rioja Zaragoza/España

    Directory of Open Access Journals (Sweden)

    García Lorza, Isabel

    1982-05-01

    Full Text Available The conditioning of this building achieved all those works necessary for the accommodation of the new functions of the college organization, as well as the structural reinforcement and renovation of the rooves which needed to be carried out. The architectural elements of great historical-artistic importance (central courtyard, stuccoes ceilings, etc. have been respected and revalued as to all their possibilities, trying to reclaim them in their real primitive state.El acondicionamiento de este edificio alcanzó a todas aquellas obras necesarias para su adecuación a las nuevas funciones de organización colegial, así como a los refuerzos estructurales y de renovación de cubiertas que su estado exigió realizar. Los elementos arquitectónicos de gran importancia histórico-artística (patio central, artesonado, etc. han sido respetados y revalorizados en todas sus posibilidades, intentando recuperarlos a su verdadero estado primitivo.

  1. Some strategies for improving caloric responses with ferroelectrics

    Science.gov (United States)

    Liu, Yang; Scott, James F.; Dkhil, Brahim

    2016-06-01

    Many important breakthroughs and significant engineering developments have been achieved during the past two decades in the field of caloric materials. In this review, we address ferroelectrics emerging as ideal materials which permit both giant elastocaloric and/or electrocaloric responses near room temperature. We summarize recent strategies for improving caloric responses using geometrical optimization, maximizing the number of coexisting phases, combining positive and negative caloric responses, introducing extra degree of freedom like mechanical stress/pressure, and multicaloric effect driven by either single stimulus or multiple stimuli. This review highlights the promising perspective of ferroelectrics for developing next-generation solid-state refrigeration.

  2. DISEÑO Y CONSTRUCCIÓN DE PROTOTIPO PARA MEDICIÓN DE FLUJO DE CALOR APLICANDO CALORIMETRÍA DIRECTA: SENSADO POR FLUJO DE CALOR

    Directory of Open Access Journals (Sweden)

    OSCAR CADENA

    2008-01-01

    Full Text Available El presente artículo describe el diseño de un prototipo inalámbrico para la medición de flujo de calor, que permita a futuro aplicar el método de calorimetría directa por gradiente de flujo de calor en el área de la electrónica médica. Esta técnica se desarrolla gracias al avance y creación de sensores que permiten medir este tipo de variables, y se postula como una alternativa a las formas de medición utilizadas actualmente, presentando mejoras en su desempeño y costo. Los resultados obtenidos luego de efectuar la calibración del equipo permiten inferir que la técnica propuesta se adapta de forma eficiente y puede utilizarse como un sustituto significativamente más ventajoso comparado con los métodos existentes en la actualidad y aplicados en el seguimiento metabólico de personas.

  3. Acondicionamiento de sensores capacitivos

    OpenAIRE

    Campos López, Pedro

    2010-01-01

    Los sensores son componentes de instrumentación cuyo objetivo principal es detectar una magnitud física del entorno y transforarla en una magnitud eléctrica. El posterior tratamiento de esta señal permite valorar la magnitud física en su unidad característica. Actualmente en el mercado se encuentra una gran variedad de sensores y la tendencia destaca su aumento año tras año. Un tipo de sensor es clasificado como sensor capacitivo, cuya característica eléctrica es el valor de...

  4. Sistemas de transmisión de calor para hornos de vía seca en la fabricación de cemento

    Directory of Open Access Journals (Sweden)

    Tonry, J. Richard

    1961-12-01

    Full Text Available Not availableEn los últimos años se han puesto en marcha numerosos sistemas para mejorar la transmisión de calor en los hornos de vía seca y, en consecuencia, el consumo de combustible en la industria del cemento. El objetivo principal ha sido el ahorro de combustible y la obtención de mayores velocidades de producción en comparación con los hornos horizontales normales. Estos sistemas pueden dividirse en dos grupos: (1 externos, donde fluyen en contracorriente sólidos y gases calientes, 71 (2 internos, con exposición de superficie y radiación de la misma como medio de transmisión de calor. Esta tendencia a sistemas de este tipo puede compararse a la que hubo hace cuarenta años con las calderas de recuperación de calor en hornos de vía seca. El primer objetivo, tanto entonces como ahora, es la mejor utilización del calor en los gases de escape.

  5. Caloric restriction and Metabolism in Lean and Obese rats.

    Data.gov (United States)

    U.S. Environmental Protection Agency — Data related to obese and lean strains of rat commonly used in the laboratory that are calorically restricted and its effects on physiologic parameters (Body...

  6. Status of selected nutrients in obese dogs undergoing caloric restriction

    OpenAIRE

    Linder, Deborah E; Freeman, Lisa M.; Holden, Shelley L; Biourge, Vincent; German, Alexander J.

    2013-01-01

    Background The purpose of this study was to test the hypothesis that dog plasma concentrations of selected nutrients decrease after undergoing caloric restriction for weight loss. Thirty-one overweight dogs that had successfully lost at least 15% of initial body weight were included in the study. Nutrients that had been previously identified to be at potential risk of deficiency during caloric restriction were measured in plasma (choline, amino acids) and urine (selenium) at the initiation an...

  7. Characteristics of non caloric dulcorants and their use in children

    Directory of Open Access Journals (Sweden)

    Calzada León Raúl

    2014-07-01

    Full Text Available This is a descriptive review of the elaboration routes, the physical and chemical characteristics, metabolism and clearance, sweetener level, residual flavor, maximal recommended ingestion, security levels and the assessment of growth and development problems in children (from newborns, including prematures, to the end of puberty, of the main no caloric edulcorants used in Mexico. The no caloric edulcorants included in this review are: aspartame, acesulfame-K, sucralose, sacarin, ciclamates, thaumatin, D- tagatose, estevia and alitame.

  8. Role of caloric homeostasis and reward in alcohol intake in Syrian golden hamsters

    OpenAIRE

    Gulick, Danielle; Green, Alan I.

    2010-01-01

    The Syrian golden hamster drinks alcohol readily, but only achieves moderate blood alcohol levels, and does not go through withdrawal from alcohol. Because the hamster is a model of caloric homeostasis, both caloric content and reward value may contribute to the hamster’s alcohol consumption. The current study examines alcohol consumption in the hamster when a caloric or non-caloric sweet solution is concurrently available and caloric intake in the hamster before, during, and after exposure t...

  9. Islas de calor urbano en Tampico, México. Impacto del microclima a la calidad del hábitat

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Fuentes Pérez

    2014-01-01

    Full Text Available De todas las modificaciones climáticas por causa urbana, las térmicas son las más conocidas por los propios ciudadanos. La acción transformadora del espacio natural sobre el que se realiza el emplazamiento de la ciudad, llega a ser productora en gran medida de sus condiciones ambientales, incluida la climatología urbana. Todo proceso de urbanización sustituye los suelos y áreas naturales por superficies construidas, cuyos materiales se caracterizan por una baja reflectividad, con disminución de la capacidad de absorción de agua y un comportamiento térmico propicio para el almacenamiento y la emisión de calor. Estos elementos coadyuvan a realzar la temperatura atmosférica de la ciudad en relación con su entorno menos urbanizado a través de un fenómeno conocido como efecto de islas de calor urbano, produciendo un impacto del microclima a la calidad del hábitat. La presente investigación experimental aplicada tiene como objetivo, demostrar la metodología de investigación adoptada, para realizar las islas de calor urbanas en Tampico, México.

  10. Diseño de un prototipo para la medición de flujo de calor mediante calorimetría directa usando sensado por variación de temperatura

    Directory of Open Access Journals (Sweden)

    Oscar Reyes

    2007-01-01

    Full Text Available Este artículo muestra las principales características del módulo para el monitoreo de flujo de calor mediante sensado de temperatura en pacientes que se encuentran en estado post-operatorio, como planteamiento de solución a los inconvenientes y falencias que presentan los actuales métodos de seguimiento del consumo de calorías. Este proyecto es un prototipo que se construye con el fin de guiar estudios posteriores sobre el tema, por lo tanto, las pruebas de calibración de flujo de calor y temperatura no se realizarán en seres humanos sino en generadores de calor controlados.

  11. Integración arquitectónica y constructiva de sistemas fotovoltaicos de tecnología de lámina delgada en relación con la disipación térmica y almacenamiento de calor

    OpenAIRE

    Cerón Vinasco, Isabel Cristina

    2014-01-01

    Esta tesis doctoral contribuye al análisis y desarrollo de nuevos elementos constructivos que integran sistemas de generación eléctrica a través de células fotovoltaicas (FV); particularmente, basados en tecnología FV de lámina delgada. Para ello se estudia el proceso de la integración arquitectónica de éstos elementos (conocido internacionalmente como “Building Integrated Photovoltaic – BIPV”) mediante diferentes metodologías. Se inicia con el estudio de los elementos fotovoltaicos existente...

  12. Changes of ampulla pressure in the semicircular canal of pigeons by caloric stimulation

    Science.gov (United States)

    Wada, Yoshiro; Suzuki, Hiroyuki; Watanabe, Satoru

    Still now several hypotheses about the mechanisms of the caloric nystagmus have been in conclusive. In this study we confirmed the convection effect and the volume change effect of the endolymph in horizontal semicircular canal following the caloric stimulation using pigeons ( Columba livia). Although the direction of the caloric nystagmus depended on the head position and the stimulus site of calorization, the caloric nystagmus disappeared after plugging of horizontal semicircular canal. On the other hand, the ampulla pressure increased by cold calorization and decreased by hot calorization and these pressure changes had no relation to the head position. These results show that the main role of the mechanisms of the caloric nystagmus under 1G is the convection effect but the volume change effect may act on the caloric nystagmus not only under 1G but also under microgravity.

  13. Principios de los métodos core y pilates y su relación con el abordaje terapéutico de la función muscular respiratoria y la capacidad de esfuerzo en personas con EPOC leve-moderada

    OpenAIRE

    Ávila Enciso, Yuri Magaly; Pineda Ortiz, Gustavo Adolfo; Salcedo Revelo, Erika Tatiana

    2013-01-01

    Objetivo: Relacionar los principios biomecánicos, fisiológicos y de control motor de los métodos Core y Pilates, el acondicionamiento de los músculos respiratorios y la tolerancia al esfuerzo en personas con EPOC. Métodos: Estudio Descriptivo – Correlacional: a partir de la recopilación, descripción y análisis de las fuentes bibliográficas se realiza una síntesis de las bases teórico-conceptuales que fundamentan la relación entre la estabilización central, función muscular respiratoria y tol...

  14. Systematic effects in CALOR simulation code to model experimental configurations

    International Nuclear Information System (INIS)

    CALOR89 code system is being used to simulate test beam results and the design parameters of several calorimeter configurations. It has been bench-marked against the ZEUS, Dθ and HELIOS data. This study identifies the systematic effects in CALOR simulation to model the experimental configurations. Five major systematic effects are identified. These are the choice of high energy nuclear collision model, material composition, scintillator saturation, shower integration time, and the shower containment. Quantitative estimates of these systematic effects are presented. 23 refs., 6 figs., 7 tabs

  15. Constrained caloric curves and phase transition for hot nuclei

    CERN Document Server

    Borderie, Bernard; Rivet, M F; Raduta, Ad R; Ademard, G; Bonnet, E; Bougault, R; Chbihi, A; Frankland, J D; Galichet, E; Gruyer, D; Guinet, D; Lautesse, P; Neindre, N Le; Lopez, O; Marini, P; Parlog, M; Pawlowski, P; Rosato, E; Roy, R; Vigilante, M

    2013-01-01

    Simulations based on experimental data obtained from multifragmenting quasi-fused nuclei produced in central $^{129}$Xe + $^{nat}$Sn collisions have been used to deduce event by event freeze-out properties in the thermal excitation energy range 4-12 AMeV [Nucl. Phys. A809 (2008) 111]. From these properties and the temperatures deduced from proton transverse momentum fluctuations, constrained caloric curves have been built. At constant average volumes caloric curves exhibit a monotonic behaviour whereas for constrained pressures a backbending is observed. Such results support the existence of a first order phase transition for hot nuclei.

  16. Modelo matemático de la transferencia de calor para predecir el perfil de durezas en probetas Jominy

    Directory of Open Access Journals (Sweden)

    López, E.

    2013-04-01

    Full Text Available The heat transfer coefficient was estimated at the bottom surface at Jominy bar end quench specimen by solution of the heat inverse conduction problem. A mathematical model based on the finite-difference method was developed to predict thermal paths and volume fraction of transformed phases. The mathematical model was codified in the commercial package Microsoft Visual Basic v. 6. The calculated thermal path and final phase distribution were used to evaluate the hardness distribution along the AISI 4140 Jominy bar.En el presente trabajo se estimó el coeficiente de transferencia de calor en la superficie que se encuentra en contacto con el chorro de agua en la probeta Jominy mediante la solución del problema inverso de conducción de calor. Con el objetivo de predecir los perfiles térmicos y las fracciones de fase transformadas se formuló un modelo matemático con el método de diferencias finitas y se codificó en el software comercial Microsoft Visual Basic v. 6. Los perfiles térmicos y las fracciones de fase calculadas se utilizaron para predecir el perfil de durezas en una probeta Jominy de acero AISI 4140 mediante el uso de correlaciones empíricas.

  17. Modelo para estudios de estabilidad de calderas de recuperación de calor (HRSG) y turbina de vapor

    OpenAIRE

    Corasaniti, Víctor Fabián; Agüero, Jorge Luis; Bianchi Lastra, Raúl E.

    2013-01-01

    En este trabajo se presenta la determinación y validación de los parámetros de un modelo digital para estudios de estabilidad que representa dos Calderas de Recuperación de Calor (HRSG, del inglés Heat Recovery Steam Generator), conjuntamente con la Turbina de Vapor a la cual suministran vapor. Los 2 HRSG producen vapor a partir de los gases de escape de 2 turbinas de gas. El modelo de simulación se implementa en el programa PSS/E (Power System Simulator), programa usado para estudios de est...

  18. VARIACIÓN EN EL TIEMPO DE LAS PROPIEDADES FÍSICAS DE UN SUELO CON ADICIÓN DE ENMIENDAS ORGÁNICAS Changes in soil physical properties over time after the addition of organic amendments

    OpenAIRE

    Oscar Seguel S.; Víctor García de Cortázar G. de C.; Manuel Casanova P

    2003-01-01

    La presente investigación tuvo como objetivo evaluar la potencialidad del bioabono y el estiércol de bovino como agente mejorador de las propiedades físicas del suelo. El bioabono aplicado provino de un biodigestor tipo Batch, mientras que el estiércol provino de una lechería. El acondicionamiento del suelo fue realizado en parcelas de 6 x 3 m, con 4 tratamientos y 3 repeticiones. Los tratamientos, en mezcla volumétrica, fueron: testigo sin acondicionar, mezcla de suelo:bioabono en relación 3...

  19. Cupula dynamics under caloric stimulation of the semicircular canal

    Science.gov (United States)

    Kondrachuk, A. V.; Sirenko, S. P.

    Caloric stimulation of the semicircular canal SC is widely applied in studies of vestibular impairments Barany 1906 suggested that caloric response of SC results from mechanism of endolymph convection due to density changes of endolymph and therefore depends on the action of gravity forces However the Skylab experiments 1983 showed that the caloric reaction of SC can take place even under microgravity The studies of Scherer Clarke 1985 Harada Ariki 1985 Baumgarten et al 1985 considered the thermal expansion of endolymph to be a concurrent mechanism The model of caloric response based on the buoyancy force due to density change in the endolymph induced by thermal stimulation was proposed by Gentine et al 1990 1991 It should be noted that the first qualitative model that took into account the effect of endolymph thermal expansion under local heating to analyze the properties of primary afferents was proposed by Gusev Orlov 1977 However these models failed to answer the question which of the mentioned effects will be dominant under certain conditions The purpose of present study was to account for the expansion and convection of endolymph and to determine under which conditions one mechanism dominates over the other The consideration is based on the following model of SC Kondrachuk Sirenko 1990 an isolated torus filled by a compressible viscous Newton liquid endolymph the torus interior is plugged by an elastic body cupula the cupula surface in contact with endolymph is supposed to be stretched along the

  20. Influence of caloric intake on experimental carcinogenesis: a review.

    Science.gov (United States)

    Kritchevsky, D; Klurfeld, D M

    1986-01-01

    The effect of caloric intake on tumor growth has been recognized for over 70 years. Inhibition of tumor growth depends primarily on the extent of caloric restriction, but tumor type, animal strain, and dietary composition all exert some influence. Caloric restriction is most effective when maintained during both initiation and promotion, but if limited to one of these phases, restriction during promotion appears to be the more effective modality. The types of tumor that have been studied include spontaneous mammary and lung tumors as well as tumors induced by organ-specific carcinogens or irradiation with ultraviolet light. Numerous investigators have studied the effects of fat, and a diet low in calories but high in fat is generally significantly more effective in inhibiting carcinogenesis than is a diet high in calories but low in fat. Mice fed high fat, low calorie diets exhibited 48% fewer chemically induced skin tumors and 61% fewer tumors induced by ultraviolet irradiation than did mice fed low fat, high calorie diets. Mice fed a diet containing 2% fat exhibited a 66% incidence of skin tumors, whereas mice fed an isocaloric diet containing 61% fat showed a 78% incidence. Rats whose diet was restricted in calories by 40% exhibited no mammary tumors (coconut oil as primary dietary fat) or 75% fewer tumors (corn oil as dietary fat) compared to ad libitum-fed controls; they also exhibited 47% fewer colonic tumors. The mechanism by which caloric restriction exerts its tumor-inhibiting effects remains to be elucidated.

  1. CALOR87: HETC87, MICAP, EGS4, and SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Gabriel, T.A.; Alsmiller, F.S.; Alsmiller, R.G. Jr.; Bishop, B.L.; Hermann, O.W.; Johnson, J.O.

    1987-01-01

    A brief history of CALOR (HETC, EGS, MICAP, SPECT) is presented to indicate the evolution of this code system. Details concerning the current modifications and additions to the high-energy transport code, HETC, are also presented and new comparisons with experimental data are included to verify the new physics improvements. 27 refs., 5 figs.

  2. Development of adherence metrics for caloric restriction interventions

    Science.gov (United States)

    Objective measures are needed to quantify dietary adherence during caloric restriction (CR) while participants are freeliving. One method to monitor adherence is to compare observed weight loss to the expected weight loss during a prescribed level of CR. Normograms (graphs)of expected weight loss ca...

  3. Development of adherence metrics for caloric restriction interventions

    Science.gov (United States)

    Objective measures are needed to quantify dietary adherence during caloric restriction (CR) while participants are freeliving. One method to monitor adherence is to compare observed weight loss to the expected weight loss during a prescribed level of CR. Normograms (graphs) of expected weight loss c...

  4. Preparados estándar de nutrición parenteral y ajuste calórico Standard parenteral nutrition preparations and caloric adjustment

    Directory of Open Access Journals (Sweden)

    J. Llop

    2009-10-01

    Full Text Available Introducción: En nutrición parenteral es necesario adecuar el aporte a los requisitos calóricos estimados. Estas necesidades se podrían cubrir mediante preparados bi/tricamerales (NPE aunque presenten rigidez en su composición. Objetivo: Evaluar la adecuación del aporte calórico al utilizar NPE, determinar los factores que la condicionan y las complicaciones asociadas. Métodos: Estudio de cohortes, observacional y prospectivo durante nueve meses en pacientes quirúrgicos. Se compararon las necesidades calculadas con el aporte real. Se estudiaron que factores condicionaban el exceso y el déficit (peso, edad, factor de estrés, altura, glucemia y trigliceridemia mediante un modelo multivariante. Se estudiaron las complicaciones metabólicas (hiperglucemias, hipertrigliceridemias asociadas al exceso o al déficit mediante la t de Student. Se compararon los cálculos teóricos de la ecuación de Harris-Benedict y de Mifflin mediante una regresión lineal-correlación. Resultados: Se estudiaron 94 pacientes. En el 87% el aporte calórico estaba dentro del rango ± 15% de la media teórica. 30 pacientes estuvieron en exceso calórico y 61 en déficit. Los pacientes de peso elevado (> 68 kg, factor de estrés superior a 1,2 e hipertrigliceridemias (> 3 mmol/L tenían mayor riesgo de déficit calórico. El 22,8% presentaron hiperglucemias que se relacionaron con exceso calórico. El 19,8% presentaron hipertrigliceridemias que se asociaron con déficit calórico. En la comparación de las dos fórmulas los valores se correlacionaban excepto en pacientes con bajo peso y edad avanzada. Discusión: Aunque la NPE se adecua a los requisitos calóricos de la mayoría de los pacientes, en pacientes con elevado peso, hipercatabolismo e hipertrigliceridemia existe un riesgo de déficit.Introduction: In parenteral nutrition it is necessary to adjust the intake to the estimated caloric requirements. These needs may be achieved by the use of bi- or

  5. The caloric vestibular nystagmus during short lasting microgravity

    Science.gov (United States)

    Oosterveld, W. J.; de Jong, H. A. A.; Kortschot, H. W.

    In human subjects the caloric vestibular test was conducted during parabolic flight. The ear irrigation was performed from 35 secs. till 5 secs. before the onset of microgravity. Nystagmography covered a 10-minutes period, including three parabolic manoeuvres of the aircraft. a. The slow phase velocity (SPV) of the caloric nystagmus increased proportionally with the value of the g-force. Introduction of microgravity induced an exponential decrease of the SPV decay. b. The nystagmus disappeared completely in microgravity, but SPV decay showed a specific time constant. c. The averaged time constant values of the caloric nystagmus SPV decay after sudden onset of microgravity and the averaged time constant of the SPV decay following a sudden stop after sustained rotation during 0-g appeared to be on the same level (10.2 s. and 10.6 s.). d. These two averaged time constant values obtained during shortlasting microgravity proved to be on a lower level than those time constants (15.5 secs.; 15.9 secs.) found in ground-based conditions. e. Because of the similarities in the characteristics of both SPV decay's and their accompanying time constants, a common working mechanism of cupular stimulation is likely. Most probably a fluid movement (or pressure) provokes a cupula deflexion followed by a cupula reflexion, either caused by a sudden stop after a sustained rotation or by a sudden onset of microgravity after g-load calorization. The present results support the Bárány convection theory with regard the endolymph stimulatory properties following the caloric test.

  6. Evaluación de un sistema de recirculación y acondicionamiento de agua en truticultura

    OpenAIRE

    Daury García-Pulido; Iván Gallego-Alarcón; Carlos Díaz-Delgado; Cheikh Fall; Cristina Burrola-Aguilar

    2011-01-01

    La principal variable crítica del crecimiento de la acuicultura en México ha sido la disponibilidad de agua en cantidad suficiente, sobre todo con calidad adecuada. En este trabajo se presenta un desarrollo tecnológico para el tratamiento de agua residual acuícola en cultivos cerrados de trucha arcoíris, como una alternativa de producción sostenible que favorece la generación de alimento de alto rendimiento y calidad nutritiva para la población. El objetivo principal de la investigación fue e...

  7. La investigación arquitectónica, el proyecto de arquitectura y el acondicionamiento ambiental en el proyecto de adecuación de la planta principal del Palacio de Carlos V de Granada

    Directory of Open Access Journals (Sweden)

    Muñoz, S

    2007-09-01

    Full Text Available The Charles V Palace is located in the Complex of Monuments of the Alhambra in Granada; despite the fact that it appears to be a fi nished building according to the design by Pedro Machuca, actually it was never completed. It is a clear example of what modern history writers would term a “longduration” building. Its main fl oor currently houses the Fine Arts Museum of Granada. The proposal to install this museum here was put forward in the 1940s, after the palace was completed in 1928 by Torres Balbás. The project was implemented by F. Prieto Moreno and the museum was opened in 1958. In 2000, the project to adapt the main fl oor of the Charles V Palace was drawn up. This project has already been implemented, although the museum project is expected to be completed in 2007. Based on architectural research, the abovementioned project includes environmental conditioning of the palace rooms, especially light, hygrothermal and air quality conditioning, as well as the installations required for exposition purposes, which mainly guarantee the visual observation of the works of art on display, conservation conditions of these works, visitors’ comfort and energy effi ciency. This article details the respectful way in which this adaptation project is meeting those objectives.El Palacio de Carlos V, situado en el Conjunto Monumental de la Alhambra de Granada, a pesar de su apariencia de edifi cio concluido de acuerdo a un proyecto, el de Pedro Machuca, no llegó a ser ejecutado en su totalidad. Constituye un claro ejemplo de lo que la historiografía moderna denominaría como edifi cio sujeto a “larga duración”. Su planta principal acoge en la actualidad el Museo de Bellas Artes de Granada. Tras el proyecto de terminación del Palacio realizado por Torres Balbás en 1928, la idea de instalar dicho museo se produce en la década de 1940, con un proyecto realizado por F. Prieto Moreno e inaugurado en 1958. En el año 2000 se redacta

  8. DETERMINACIÓN EXPERIMENTAL DE LA CANTIDAD DE CALOR EMITIDA POR UN CIRCUITO ELECTRÓNICO EXPERIMENTAL MEASUREMENT OF THE AMOUNT OF HEAT GENERATED BY AN ELECTRONIC CIRCUIT

    Directory of Open Access Journals (Sweden)

    Jeison Marín

    2012-06-01

    Full Text Available El presente artículo describe un calorímetro que en la actualidad se utiliza para la determinación experimental de la cantidad de calor generado por circuitos electrónicos con la particularidad de permitir la entrada de potencia eléctrica al circuito electrónico bajo ensayo, para poder hacer seguimiento de su dinámica de generación de calor por efecto Joule. Para ello, se construyeron varios circuitos electrónicos básicos y cuyos resultados se presentan. Se logró de esta manera disponer de un sistema que permite contrastar las predicciones teóricas realizadas por un diseñador en cuanto a la generación de calor, frente a resultados experimentales.This article describes a calorimeter created for the experimental determination of the amount of heat generated by an electronic circuit. It has the particularity of allowing the power input to the electronic circuit under experiment, with the purpose of making possible to follow its dynamic heat flows generation by Joule effect. Several simple electronic circuits were making and their results are presented. In this way, there is now available a system which allows to evaluate the proposed theoretical predictions done by a designer and related to the heat generation, against experimental results.

  9. Ejercicios físicos para el acondicionamiento de la mano del pianista: acercamiento a su sentido y aplicación a partir de un estudio de su repertorio

    OpenAIRE

    Illera Ordóñez, Fernando Andrés

    2015-01-01

    El presente artículo pretende proponer ejercicios físicos para el acondicionamiento de la mano del pianista a partir de una descripción fisiológica y técnica de su repertorio canónico -- Su proposición también incluye la problematización de su planteamiento y abre posibilidades secundarias de reflexión acerca de la “correcta” técnica pianística, así como su pertinencia e importancia para el pianista en formación

  10. Estudio de máquinas de absorción con la disolución nitrato de litio-amoniaco : ciclos híbridos potenciados con compresión mecánica

    OpenAIRE

    Ventas Garzón, Rubén

    2010-01-01

    En esta Tesis doctoral se lleva a cabo un estudio de máquinas de absorción para refrigeración que sean capaces de funcionar con menores temperaturas de generación que los ciclos basados en simple efecto. Esto permitiría aprovechar calores residuales y calor solar a menor temperatura con la consiguiente reducción de emisiones de CO2. Los ciclos híbridos de absorción basados en simple efecto, potenciados con compresión mecánica, ofrecen esta posibilidad además de permitir una modulación en pote...

  11. Calefacción por bomba de calor geotérmica utilizando los refrigerantes de nueva generación

    OpenAIRE

    Lázaro Lozano, Cristina

    2009-01-01

    El objetivo principal de este proyecto es desarrollar un sistema de calefacción mediante una bomba de calor geotérmica, con la particularidad de que funcionará con refrigerantes de nueva generación. Se hará una comparación económica y energética entre los nuevos refrigerantes y los hasta ahora utilizados. También será objeto de comparación la emisión de dióxido de carbono. El motivo de las sustitución de los refrigerantes comunmente utilizados por otros es reducir los efectos medioambientales...

  12. Solar thermal power plants for heat and electricity generation; Presentacion de plantas termosolares para generacion de calor y energia electrica

    Energy Technology Data Exchange (ETDEWEB)

    Estrada Cajigal, V. [Solartronic S. A. de C. V., Cuernavaca (Mexico); Manzini, F.; Sanchez, A. [Laboratorio de Energia Solar (IIM-UNAM), Temixco (Mexico)

    1992-12-31

    Solar thermal technology is presented for concentration into a point for the production of heat and energy in small and large scale, emphasis is made on the capacity for the combination with current technologies using fossil fuels for electricity generation and process steam, increasing the global efficiency of the power plants and notably reducing the pollutants emission to the air during the insolation hours. It is successfully compared with other solar-thermal technologies. [Espanol] Se presenta la tecnologia termosolar de concentracion puntual para produccion de calor y de energia en pequena y gran escala, se enfatiza su capacidad de combinacion con las tecnologias actuales que utilizan combustibles fosiles para produccion de electricidad y vapor de proceso, aumentando la eficiencia global de las plantas y reduciendo notablemente sus emisiones contaminantes a la atmosfera durante las horas de insolacion. Se le compara exitosamente con otras tecnologias termosolares.

  13. Análisis de la dispersión axial de masa y calor en reactores de lecho fijo

    Directory of Open Access Journals (Sweden)

    Rangel Jara Hermes Augusto

    2011-06-01

    Full Text Available Dentro del espíritu investigativo a nivel teórico del estudio de los reactores químicos, el presente trabajo desarrolla e implementa un análisis conceptual y numérico de los fenómenos de dispersión axial de calor y masa en reactores de lecho fijo. Se pretende disponer de una alternativa numérica que permita en una forma rápida y precisa la solución de las ecuaciones diferenciales junto con las respectivas condiciones de frontera del modelo matemático. Para la simulación del reactor de lecho fijo se empleó un modelo unidimensional pseudohomogeneo con parámetros aglomerados.

  14. Caloric values for young sprouts of nine hardwood species

    Energy Technology Data Exchange (ETDEWEB)

    Neenan, M. (An Foras Taluntais, Oak Park, Carlow, Ireland); Steinbeck, K.

    1979-09-01

    Caloric content, specific gravity, and ash content of 6- to 15-year-old sprouts of nine hardwood species were determined in midsummer. Energy values for wood, bark, first order branches, twigs, and leaves were determined with an adiabatic bomb calorimeter. The values found for coppice material averaged 4791 cal/g and were comparable to published values for older wood. Intraspecific differences among tissues were greater than the relatively small but significant differences among species. Differences in yield potential are therefore likely to outweigh variations in caloric content among species where total energy production per unit of land area is concerned. Ash content varied from 0.65 percent for wood to 5.88 percent for bark.

  15. The urban climate: urban heat island of Salamanca El clima de las ciudades: isla de calor de Salamanca

    Directory of Open Access Journals (Sweden)

    Mª Salud Alonso García

    2004-12-01

    Full Text Available We have determined the existence of the urban heat island (UHI in a medium-sized city, with an extreme climate and few important foci of industrial pollution. It was seen that urban warming can arise in cities of these characteristics, being able to influence in the alive beings of the zone. By comparing the temperature series in an urban area and those from a nearby rural area, we studied the temporal evolution of the intensity of the UHI for the three-year period between 1996 and 1998. We detected two phenomenons: nocturnal heat island, when the difference of temperature between city and rural zone is positive, and diurnal heat island, when is negative. The most intense nocturnal heat island was seen in autumn, and the most intense diurnal heat island was seen in spring. Statistical study of the annual series corresponding to the night-time heat island permits a definition for Salamanca: a weak island, such as the one showing an intensity lower than 2.0 oC, a moderate island, if the intensity lies between 2.0 oC and 4.0 oC, and an intense island when a values greater than 4.0 oC is passed.En este trabajo se ha determinado la existencia de la isla de calor urbana (ICU, en una ciudad de tamaño medio, con un clima extremado y focos industriales de poca actividad. Con lo que se puede comprobar cómo afecta el calentamiento urbano a ciudades de estas características, pudiendo influir en los seres vivos de la zona. La existencia del fenómeno isla de calor, y su evolución en el tiempo, se han observado comparando los datos de temperatura registrados en una estación meteorológica situada en la ciudad, con los de otra estación fuera del radio de acción de la urbe, durante el período 1996-1998. Se han detectado dos fenómenos: la isla de calor nocturna, cuando la diferencia térmica entre la ciudad y la zona rural es positiva, que presenta sus valores más altos en otoño, y la isla de calor diurna, cuando la diferencia es negativa, que

  16. Caloric Restriction Enhances Fear Extinction Learning in Mice

    OpenAIRE

    Riddle, Megan C; McKenna, Morgan C.; Yoon, Yone J; Pattwell, Siobhan S.; Santos, Patricia Mae G; Casey, B. J.; Glatt, Charles E.

    2013-01-01

    Fear extinction learning, the ability to reassess a learned cue of danger as safe when it no longer predicts aversive events, is often dysregulated in anxiety disorders. Selective serotonin reuptake inhibitors (SSRI's) enhance neural plasticity and their ability to enhance fear extinction learning may explain their anxiolytic properties. Caloric restriction (CR) has SSRI-like effects on neural plasticity and anxiety-related behavior. We implemented CR in mice to determine its effects on condi...

  17. Early postnatal caloric restriction protects adult male intrauterine growth-restricted offspring from obesity.

    Science.gov (United States)

    Garg, Meena; Thamotharan, Manikkavasagar; Dai, Yun; Thamotharan, Shanthie; Shin, Bo-Chul; Stout, David; Devaskar, Sherin U

    2012-06-01

    Postnatal ad libitum caloric intake superimposed on intrauterine growth restriction (IUGR) is associated with adult-onset obesity, insulin resistance, and type 2 diabetes mellitus (T2DM). We hypothesized that this paradigm of prenatal nutrient deprivation-induced programming can be reversed with the introduction of early postnatal calorie restriction. Ten-month-old male rats exposed to either prenatal nutrient restriction with ad libitum postnatal intake (IUGR), pre- and postnatal nutrient restriction (IPGR), or postnatal nutrient restriction limited to the suckling phase (50% from postnatal [PN]1 to PN21) (PNGR) were compared with age-matched controls (CON). Visceral adiposity, metabolic profile, and insulin sensitivity by hyperinsulinemic-euglycemic clamps were examined. The 10-month-old male IUGR group had a 1.5- to 2.0-fold increase in subcutaneous and visceral fat (P metabolic inflexibility (Vo(2)) versus CON. The IPGR group remained lean, euglycemic, insulin sensitive, and active while maintaining metabolic flexibility. The PNGR group was insulin sensitive, similar to IPGR, but less active while maintaining metabolic flexibility. We conclude that IUGR resulted in obesity without insulin resistance and energy metabolic perturbations prior to development of glucose intolerance and T2DM. Postnatal nutrient restriction superimposed on IUGR was protective, restoring metabolic normalcy to a lean and active phenotype. PMID:22461568

  18. Hybrid system: Heat pump-solar air dryer for grains; Sistema hibrido: bomba de calor - calentador solar de aire para el secado de productos agricolas

    Energy Technology Data Exchange (ETDEWEB)

    Soto Gomez, Willfredo [Instituto Tecnologico de Tijuana, Tijuana (Mexico); Ortega Herrera, Jose Angel [Instituto Politecnico Nacional, Mexico, D.F. (Mexico)

    2000-07-01

    Design, building, operation and evaluation energy wise of a hybrid experimental type, with heat pump, that uses no chloride, does not destroy the ozone layer. It is solar air dryer for grains. In this research we dry rice. It has tree systems: 1.- A mechanical compression heat pump, 2.- An air solar heater, and 3.- An agriculture products dryer. The drying capacity is 20 pounds of grain /day, with a median daily solar radiation. The costs is approximately U.S. $ 6 000.00. The heat pump used 22 refrigerant first, and now works with refrigerant SUVA 9000. This refrigerant will be available this year in the I.S., it is one of the ecological class that substitutes the chlorofluorocarbonates. [Spanish] Se disena, construye, opera, y evalua energeticamente, un sistema hibrido tipo experimental, con bomba de calor que utiliza refrigerante que no contiene cloro, y no destruye la capa de ozono y un calentador solar de aire, para secar granos. En este trabajo secamos arroz. Se compone de tres sistemas: 1.- Bomba de calor por compresion mecanica, 2.- Calentador solar de aire, 3.- Secador de productos agricolas. La capacidad de secado es de 10 Kilos de granos/dia promedio. Tiene un costo aproximado de $ 60 000. La bomba de calor utiliza refrigerante 22 en una primera generacion, y actualmente opera con un refrigerante SUVA 9000, en una segunda generacion, este refrigerante se comercializara en este ano, en la Union Americana, pertenece a la familia de los llamados refrigerantes ecologicos, sustitutos de los clorofluorocarbonados.

  19. Estudio y Modelado de una Bomba de Calor con CO2

    OpenAIRE

    Monticelli, Giuseppe

    2009-01-01

    CFCs (chlorofluorocarbons) have been abolished and HCFCs (hydrochlorofluorocarbons) are in process of being abolished as working fluids due to their high global warming potential (GWP) and ozone depletion potential (ODP). CO2 is non-toxic, non-flammable, has zero ODP and negligible GWP as working fluid. In the present work the behavior of transcritical CO2 from the point of view of its thermal and mechanical properties through the correlations of Gnielinski (1976), Pitla (2002)...

  20. Estudio secuencial y cuantitativo del quimerismo hemopoyético en pacientes sometidos a un trasplante alogénico de progenitores hemopoyéticos con depleción linfoide T o con acondicionamiento sub-mieloablativo.

    OpenAIRE

    Fernández Avilés, Francesc

    2004-01-01

    [spa] El objetivo principal de esta Tesis Doctoral es analizar cual es la frecuencia y la relevancia clínica de la persistencia de células linfoides T y de células mieloides originarias del receptor (quimerismo mixto) tras un trasplante alogénico de progenitores hemopoyéticos. La hipótesis de trabajo es comprobar si el estudio secuencial y cuantitativo del patrón de quimerismo mixto en linfocitos T y en neutrófilos permite predecir el rechazo del injerto alogénico o la recidiva leucémica, res...

  1. The Lexicocalorimeter: Gauging public health through caloric input and output on social media

    CERN Document Server

    Alajajian, S E; Reagan, A J; Alajajian, S C; Frank, M R; Mitchell, L; Lahne, J; Danforth, C M; Dodds, P S

    2015-01-01

    We propose and develop a Lexicocalorimeter: an online, interactive instrument for measuring the "caloric content" of social media and other large-scale texts. We do so by constructing extensive yet improvable tables of food and activity related phrases, and respectively assigning them with sourced estimates of caloric intake and expenditure. We show that for Twitter, our naive measures of "caloric input", "caloric output", and the ratio of these measures---"caloric balance"---are all strong correlates with health and well-being demographics for the contiguous United States. Our caloric balance measure outperforms both its constituent quantities, is tunable to specific demographic measures such as diabetes rates, provides a real-time signal reflecting a population's health, and has the potential to be used alongside traditional survey data in the development of public policy and collective self-awareness. Because our Lexicocalorimeter is a linear superposition of principled phrase scores, we also show we can m...

  2. La isla de calor estival en Temuco, Chile

    Directory of Open Access Journals (Sweden)

    Alicia Capelli de Steffens

    2001-01-01

    Full Text Available Temuco es una ciudad localizada en el centro sur de Chile (38º 45’ S y 72º 40’ W. Morfológicamente, el sitio de la ciudad corresponde a las terrazas fluviales del río Cautín que se desarrollan en forma encajonada entre los cerros Ñielol (350 m y Conunhueno (360 m. Esta ciudad se ha desarrollado rápidamente en las últimas décadas, por lo tanto es necesario conocer el efecto antrópico en la misma. Para evaluar parte de ese efecto se analiza la isla de calor urbana estival en la ciudad de Temuco, Chile. Se efectuaron mediciones de temperatura del aire y humedad a través de la ciudad para determinar la forma y la intensidad de la isla de calor urbano. Se utilizaron estaciones móviles e información de una estación meteorológica fija. La ciudad presenta un comportamiento térmico diferente a lo largo del día. Durante el día genera una isla de calor que responde en líneas generales al modelo ideal de calentamiento urbano. La intensidad de la isla calórica (∆Tu-r fue 6.3ºC y 1.2ºC durante el día y la noche, respectivamente. La influencia de los cerros que limitan la ciudad es importante. El estudio confirma la idea que el clima urbano de una ciudad es un mosaico de microclimas que interactuan continuamente.

  3. Perspective food addiction, caloric restriction, and dopaminergic neurotransmission

    DEFF Research Database (Denmark)

    Stankowska, Arwen Urrsula Malgorzata; Gjedde, Albert

    2013-01-01

    for a reduced cognitive reward condition. The combination of caloric restriction and food addiction imparts a high risk of relapse as a result of further reduction of dopaminergic neurotransmission and the subsequent loss of reward. As with drugs of abuse, ingestion of large quantities of sugar in circumstances......, and reduced activity in prefrontal regions of the cerebral cortex. The neurobiological characteristics suggest that obese people also have a pathological dependence in common with addicts, in the form of food addiction. Malnutrition and dieting both relate to binge eating, possibly as a compensation...

  4. Caloric restriction: beneficial effects on brain aging and Alzheimer's disease.

    Science.gov (United States)

    Van Cauwenberghe, Caroline; Vandendriessche, Charysse; Libert, Claude; Vandenbroucke, Roosmarijn E

    2016-08-01

    Dietary interventions such as caloric restriction (CR) extend lifespan and health span. Recent data from animal and human studies indicate that CR slows down the aging process, benefits general health, and improves memory performance. Caloric restriction also retards and slows down the progression of different age-related diseases, such as Alzheimer's disease. However, the specific molecular basis of these effects remains unclear. A better understanding of the pathways underlying these effects could pave the way to novel preventive or therapeutic strategies. In this review, we will discuss the mechanisms and effects of CR on aging and Alzheimer's disease. A potential alternative to CR as a lifestyle modification is the use of CR mimetics. These compounds mimic the biochemical and functional effects of CR without the need to reduce energy intake. We discuss the effect of two of the most investigated mimetics, resveratrol and rapamycin, on aging and their potential as Alzheimer's disease therapeutics. However, additional research will be needed to determine the safety, efficacy, and usability of CR and its mimetics before a general recommendation can be proposed to implement them. PMID:27240590

  5. Lifelong caloric restriction increases working memory in mice.

    Directory of Open Access Journals (Sweden)

    Angela Kuhla

    Full Text Available Caloric restriction (CR is argued to positively affect general health, longevity and the normally occurring age-related reduction of cognition. This issue is well examined, but most studies investigated the effect of short-term periods of CR. Herein, 4 weeks old female mice were fed caloric restricted for 4, 20 and especially for 74 weeks. CR mice received 60% of food eaten by their ad libitum (AL fed littermates, and all age-matched groups were behaviorally analyzed. The motor coordination, which was tested by rotarod/accelerod, decreased age-related, but was not influenced by the different periods of CR. In contrast, the age-related impairment of spontaneous locomotor activity and anxiety, both being evaluated by open field and by elevated plus maze test, was found aggravated by a lifelong CR. Measurement of cognitive performance with morris water maze showed that the working memory decreased age-related in AL mice, while a lifelong CR caused a better cognitive performance and resulted in a significantly better spatial memory upon 74 weeks CR feeding. However, a late-onset CR feeding in 66 weeks old mice did not ameliorate the working memory. Therefore, a lifelong CR seems to be necessary to improve working memory.

  6. Lifelong caloric restriction increases working memory in mice.

    Science.gov (United States)

    Kuhla, Angela; Lange, Sophie; Holzmann, Carsten; Maass, Fabian; Petersen, Jana; Vollmar, Brigitte; Wree, Andreas

    2013-01-01

    Caloric restriction (CR) is argued to positively affect general health, longevity and the normally occurring age-related reduction of cognition. This issue is well examined, but most studies investigated the effect of short-term periods of CR. Herein, 4 weeks old female mice were fed caloric restricted for 4, 20 and especially for 74 weeks. CR mice received 60% of food eaten by their ad libitum (AL) fed littermates, and all age-matched groups were behaviorally analyzed. The motor coordination, which was tested by rotarod/accelerod, decreased age-related, but was not influenced by the different periods of CR. In contrast, the age-related impairment of spontaneous locomotor activity and anxiety, both being evaluated by open field and by elevated plus maze test, was found aggravated by a lifelong CR. Measurement of cognitive performance with morris water maze showed that the working memory decreased age-related in AL mice, while a lifelong CR caused a better cognitive performance and resulted in a significantly better spatial memory upon 74 weeks CR feeding. However, a late-onset CR feeding in 66 weeks old mice did not ameliorate the working memory. Therefore, a lifelong CR seems to be necessary to improve working memory.

  7. Modelación y simulación de disipadores de calor para procesadores de computadora en COMSOL Multiphysics Modeling and simulation of heat sinks for computer processors in COMSOL Multiphysics

    Directory of Open Access Journals (Sweden)

    Sulin Garro Acón

    2012-11-01

    Full Text Available En este estudio se analizó la transferencia de calor en tres disipadores de calor utilizados para enfriar los procesadores de computadoras de escritorio. El objetivo de estos disipadores es evitar el sobrecalentamiento de la unidad de procesamiento y la consecuente reducción de la vida útil del computador. Los disipadores de calor se modelaron usando COMSOL Multiphysics con las dimensiones reales de los dispositivos y la generación de calor se modeló con una fuente puntual. Luego se modificaron los diseños de los disipadores para lograr una temperatura más baja en la zona más caliente del procesador. El resultado fue una reducción en la temperatura en el rango de 5-78 grados Kelvin, al rediseñarse el disipador de calor con variaciones feasibles como la reducción del grosor de las placas de intercambio de calor y el aumento de su número. Esto demuestra la posibilidad de desarrollar diseños optimizados para disipadores de calor que no requieran más materiales sino una mejor ingeniería. El trabajo se inició como parte del curso CM-4101 Modelización y Simulación.In this study, the heat transfer of three desktop- computer heat sinks was analyzed. The objective of using these heat sinks is to avoid overheating of the computer’s processing unit and in turn reduce the corresponding loss in the unit’s service time. The heat sinks were modeled using COMSOL Multiphysics with the actual dimensions of the devices, and heat generation was modeled with a point source. In the next step, the heat sink designs were modified to achieve a lower temperature in the higher temperature location on the heat sink. The results were temperature reductions in the range of 5-78 degrees Kelvin, by making feasible variations in design such as reducing the thickness of the heat exchanger fins and increasing their number. This paper demonstrates that there is room to develop improved designs that do not require more materials but rather a better engineering

  8. Transferencia de calor en la colada continua de aceros. II parte. Enfriamiento secundario

    Directory of Open Access Journals (Sweden)

    Cicutti, C.

    1997-12-01

    Full Text Available Once the strand leaves the mold, the solidification of steel progresses due to the heat extracted in the secondary cooling zone of the continuous casting machine. In this zone, heat is extracted mainly by: the incidence of water from sprays, radiation to surroundings contact with rolls and run out water accumulated between rolls and strand. In this work, all these mechanisms are evaluated and, when it is possible, they are quantified. Methods which are usually employed to measure solidification profiles in the continuous casting machine are also reviewed. Finally, the incidence of secondary cooling on the quality of cast products is discussed.

    La solidificación del acero iniciada en el molde continúa en la zona de enfriamiento secundario de la máquina donde el calor es extraído, principalmente por la incidencia del agua de los rociadores, la radiación al medio ambiente, el contacto con los rodillos y el agua acumulada en ellos. En este trabajo se revisa cada uno de estos mecanismos determinando, en los casos en que es posible, valores cuantitativos de los mismos. Además, se analizan los distintos métodos empleados para medir el avance del espesor solidificado en la máquina de colada continua. Por último, se discute la incidencia del enfriamiento secundario en la calidad final de los productos colados.

  9. Absorption refrigeration using waste heat; Refrigeracion por absorcion utilizando calor de desecho

    Energy Technology Data Exchange (ETDEWEB)

    Heard, Christopher; Ayala, Ramon; Best, Roberto [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1994-07-01

    In this article a detailed analysis is made of the absorption refrigeration system that uses waste heat and because of being of low temperature, can make the processes more efficient being at the same time an important factor in the country`s energy resources saving, since the system permits to increase the availability of electricity and fuel`s energy. The Instituto de Investigaciones Electricas (IIE) and the Universidad Nacional Autonoma de Mexico (UNAM) absorption refrigeration experience is described and the economic aspects related with this system are analyzed. [Espanol] En este articulo se presenta un analisis detallado del sistema de refrigeracion por absorcion que utiliza calor de desecho y que, siendo de baja temperatura, puede hacer mas eficientes los procesos y ser a la vez un factor importante en el ahorro de los recursos energeticos del pais, pues el sistema permite aumentar la disponibilidad energetica de electricidad y combustibles. Se describe la experiencia del Instituto de Investigaciones Electricas (IIE) en refrigeracion por absorcion y la de la Universidad Nacional Autonoma de Mexico (UNAM), y se analizan los aspectos economicos relacionados con este sistema.

  10. Modelo para la Simulación en Estado Estable de Redes de Recuperación de Calor Model for Steady State Simulation of Heat Recovery Networks

    Directory of Open Access Journals (Sweden)

    M Picón-Núñez

    2004-01-01

    Full Text Available En este trabajo se desarrolla un modelo para la simulación en estado estable de redes de recuperación de calor considerando una sola fase. Se utilizan el modelo básico de la efectividad térmica y de las relaciones con el Número de Unidades de Transferencia de Calor para la simulación de la operación de intercambiadores de calor. La aplicación del modelo se demuestra en un caso de estudio tomado de la literatura donde se determinan las nuevas temperaturas de una red una vez que las perturbaciones de tipo flujo másico y temperatura entran al sistema. Se concluye que la simulación en estado estable desarrollada entrega resultados confiables.In this work, a model for the steady state simulation of heat recovery networks in single phase is developed. The basic model of the thermal effectiveness and its relation to the Number of Heat Transfer Units are used for the simulation of the operation of heat exchangers. The application of the model is demonstrated for a study case from the literature where network temperatures are calculated after perturbation to the flow rate and to the temperature are introduced into the system. It is concluded that the steady state simulation developed in this work gives reliable results.

  11. Modelamiento y simulación del efecto de la entrada de calor en la penetración de una junta soldada

    Directory of Open Access Journals (Sweden)

    Lina Gómez

    2003-01-01

    Full Text Available En esta investigación se realizó el simulador SimVol, en el cual se experimentó con el fin de encontrar una relación entre la entrada de calor y la penetración de la junta soldada. SimVol se basó en un modelo en 2D, que describe el flujo de calor y el flujo de metal líquido en el charco de una soldadura realizada con el proceso GTAW (Gas Tungsten Arc Welding. En el modelo matemático se incluyen las ecuaciones de Navier-Stokes y la ecuación de energía, las cuales constituyen un sistema de ecuaciones diferenciales parciales de segundo orden, no-lineales, no homogéneas y transitorias. El modelo numérico se desarrolla en Volúmenes Finitos en un esquema totalmente implícito, con malla regular y escalonada; además, debido al desconocimiento del campo de presión es necesario utilizar el algoritmo SIMPLE (Semi-Implicit Method for Pressure-Linked Equations. La investigación también incluye una serie de experimentos que permitieron validar el modelo planteados.

  12. Análisis exergético comparativo entre intercambiadores de calor // A comparative exergetic analysis of compact heat exchangers

    Directory of Open Access Journals (Sweden)

    Rubén Borrajo-Pérez

    2011-08-01

    Full Text Available Los intercambiadores de calor son equipos de importancia primordial en la industria y enaplicaciones domésticas en general. El trabajo está relacionado con el area de la intensificacion de latransferencia de calor en intercambiadores de calor compactos y la comparación entre diferentestipos de superficies intensificadas. La comparación es realizada a partir del análisis de la exergíadestruída por la superfície de intercambio como resultado de las perdidas por fricción y delintercambio térmico entre cuerpos con diferencia finita de temperaturas. El análisis de Segunda Leyde la Termodinámica permite identificar en que superfície de intercambio se genera mas entropía.Como resultado fundamental se obtiene la dependencia entre la exergía destruída y elespaciamiento transversal para una superfície formada por una fila de tubos elipticos a diferentesvalores del numero de Reynolds. Se identifica al intercambio térmico como la de mayor aporte a laentropía generada. Finalmente se demuestra la viabilidad de la intensificación de la transferencia decalor empleando generadores de vórtices en intercambiadores de calor.Palabras claves: generadores de vórtices, intecambiadores de calor compactos, tubos elípticos, exergía.__________________________________________________________________AbstractThe heat exchangers are important devices in both industry and household applications. This work isabout heat transfer enhancement in heat exchangers surface. Many heat transfer enhancementtechniques can be applied and then a comparative tool is needed to evaluate its performance.Thermodynamics is one of these tools and the exergetic analysis can be applied to heat exchangersurfaces. The exergy destroyed because both of thermal exchange between bodies with differenttemperatures and destroyed by friction drag is calculated. These results are used to compare heatexchanger surfaces. Heat exchanger surfaces in smooth configuration and the same surfaces

  13. Coeficientes de transferencia de calor experimental para el enfriamiento de licor en intercambiadores de placas//Experimental heat transfer coefficients for the liquor cooling in plate heat exchanger

    Directory of Open Access Journals (Sweden)

    Enrique Torres‐Tamayo

    2014-01-01

    Full Text Available La pérdida de eficiencia del proceso de enfriamiento del licor amoniacal, mediante el uso de intercambiadores de calor de placas, está asociada a imprecisiones en la estimación de los coeficientes de transferencia de calor y la acumulación de incrustaciones en la superficie de intercambio. El objetivo de la investigación es determinar los coeficientes de transferencia de calor y la influencia de lasincrustaciones en la pérdida de eficiencia de la instalación. Mediante un procedimiento iterativo se estableció la ecuación del número de Nusselt y su relación con el número de Reynolds y Prandtl. Se utilizó un diseño experimental multifactorial. Los resultados predicen el conocimiento de los coeficientespara el cálculo del número de Nusselt en ambos fluidos. Los valores de los coeficientes del licor amoniacal son inferiores, ello se debe a la presencia de componentes gaseosos. La ecuación obtenida muestra correspondencia con el modelo de Buonapane, el error comparativo es del 3,55 %.Palabras claves: intercambiador de calor de placas, coeficientes de transferencia de calor, eficiencia térmica.______________________________________________________________________________AbstractThe loss of efficiency of the ammonia liquor cooling process, by means of the plate heat exchanger, is associated to the incorrect estimate of the heat transfer coefficients and the accumulation of inlays in the exchange surface. The objective of the investigation is to determine the transfer coefficients and the influence of the inlays in the efficiency loss of the installation. By means of an iterative procedure was obtained the Nusselt number equation and the relationship with the Reynolds and Prandtl number, for it was used it a design experimental multifactorial. The results predict the knowledge of the coefficients forthe calculation of the Nusselt number for both fluids. The ammonia liquor coefficients values are inferior, due to the presence of gassy

  14. Study of the internal heat transfer of the water flow in nucleate boiling; Estudio de la transferencia de calor del flujo interno de agua en ebullicion nucleada

    Energy Technology Data Exchange (ETDEWEB)

    Payan Rodriguez, Luis Alfredo

    2003-09-01

    propuestos se utilizaron en un caso de estudio derivado de un problema real en una planta termoelectrica, donde se requeria simular el proceso de ebullicion en los tubos del hogar del generador de vapor para determinar las causas de las fallas que ocurrieron en un numero considerable de tubos. Con los resultados obtenidos se logro establecer que las fallas en los tubos del generador de vapor analizado se debieron a que la relacion de transferencia de calor en el hogar alcanzo valores criticos que provocaron la desviacion de la ebullicion nucleada a ebullicion pelicular, ocasionando la disminucion del coeficiente de transferencia de calor con el consecuente incremento subito en la temperatura de la pared del tubo.

  15. Cementos con cenizas volantes

    Directory of Open Access Journals (Sweden)

    Ossa M., Mauricio

    1984-03-01

    additions of 20 and 30% .

    Casi la generalidad de los estudios realizados sobre cementos con adición de cenizas volantes se refieren a sus características y comportamiento en pastas, morteros y hormigones, siempre en relación con aquéllos del cemento portland. Esta vez, se desarrolló un trabajo experimental orientado a relacionar entre sí los cementos con adiciones de cenizas volantes y de puzolana natural. Para ello se fabricaron a escala de laboratorio cementos de ambos tipos, empleando como materias primas comunes clinker y yeso y, como variables, diferentes porcentajes de las dos adiciones, que cumplieron previamente los requisitos normalizados en cuanto a sus actividades puzolánicas. La calidad de los cementos fabricados resultó adecuada y concordante con la del cemento portland-puzolánico obtenido a escala industrial con los mismos clinker, yeso y puzolana natural de este estudio. Posteriormente, se determinaron las características de los cementos experimentales y se confeccionaron morteros normales para la realización de ensayos físicos y mecánicos. Los resultados de ensayos indicaron que los cementos con adición de cenizas volantes (CCV requieren menos agua para consistencia normal, presentan tiempos de fraguado mayores y expansiones en autoclave menores que los cementos con adición de puzolana (CP. Los calores de hidratación a 7 y 28 días de edad fueron aproximadamente similares para ambos tipos de cemento. En morteros normales, los cementos CCV mostraron menor retracción de secado, mayor retentividad y mayor fluidez (para igual cantidad de agua que los cementos CP. En los ensayos de exudación se observó que ésta depende más de la finura que el tipo de adición. Finalmente, los ensayos mecánicos señalaron que las resistencias a compresión y flexotracción de los morteros con cementos CCV son menores a edades inferiores que 14 días (del orden de 5 a 10% a un día de edad, pero que a partir de entonces pasan a ser mayores que las de

  16. Tolerancia al calor y humedad atmosférica de diferentes grupos raciales de ganado bovino

    Directory of Open Access Journals (Sweden)

    Ariel Guillén T

    2011-04-01

    Full Text Available Objetivo. Comparar algunas respuestas fisiológicas al calor y humedad atmosférica entre bovinos Chinampos (Bos taurus; Ch, ½ Charolais ½ Brahman (CB, Holstein (H y Jersey (J. Materiales y métodos. Se realizó un estudio en La Paz, México. Se utilizaron 12 vacas H, 10 J, 15 Ch y 8 CB. Durante el verano se midieron cada semana (a las 0600 y 1600 horas la frecuencia respiratoria (FR y temperatura rectal (TR. Se registraron las variables climáticas para calcular el índice de temperatura-humedad (ITH. Resultados. Durante todo el verano, la FR en los cuatro grupos estuvo por encima de los valores fisiológicos para el ganado bovino, siendo superior en H y J que en Ch y CB (p<0.01. En todos los grupos, la TR estuvo dentro de los límites fisiológicos de la especie estudiada. El grupo racial más afectado fue H (p<0.05. Cuando las constantes fisiológicas fueron analizadas dentro de cada una de tres categorías de ITH (<72, ≥72<78, y ≥78, las vacas H y J mostraron FR superior a las Ch y CB (p<0.01. La TR aumentó conforme se elevó el ITH siendo más marcado en J y H. El incremento de la FR entre la mañana y la tarde de cada día de medición fue mayor en H y J que en Ch y CB (p<0.05. La TR se incrementó más en H que en Ch (p<0.05. Conclusiones. Los grupos raciales más tolerantes al estrés por calor, determinado con base en FR y TR fueron Ch y CB.

  17. Heat transfer in simple houses; Transferencia de calor en casas habitacion

    Energy Technology Data Exchange (ETDEWEB)

    Porta, Miguel Angel; Rubio, Eduardo; Fernandez, Jose Luis [Centro de Investigaciones Biologicas del Noroeste, Baja California Sur, (Mexico); Gomez Munoz, Victor [Centro Interdiciplinario de Ciencias Marinas, Baja California Sur (Mexico)

    2000-07-01

    habitacion bajo distintas combinaciones de factores geometricos, incluyendo la orientacion de la vivienda, los parteluces y otros protectores de la fachada, los materiales y los metodos constructivos. El articulo presenta el balance energetico del sistema, que aqui se representa mediante tres ecuaciones de equilibrio energetico, que describen cada una, la ventana, la obra de mamposteria y el aire interior. La solucion simultanea de las ecuaciones diferenciales se obtiene por el metodo de Kutta, de la que se despejan las temperaturas medias representativas de cada uno de los elementos anteriores, y se calcula el flujo de calor entre ellos a lo largo del dia, asi como los flujos de intercambio con el exterior.

  18. Low Caloric Sweeteners for Diabetes and Obesity Care and Their

    Directory of Open Access Journals (Sweden)

    Mohammad Asif

    2015-10-01

    Full Text Available Diabetes and obesity are two common human disorders that affecting human health and invite various diseases and disorders in normal body functions. These diseases are very common worldwide. Diabetes occurs when high blood sugar levels develop. This happens when body can’t make and use all of the insulin it needs to blood sugar normally to keep blood sugar levels as normal as possible to control diabetes. Diabetic patients will need to follow a diet plan, do exercise and possibly take insulin injections. As part of eating plan, health care provider, and dietitian may ask to limit the amount of carbohydrates eat each day. Low-calorie sweeteners are one easy tool to help for follow eating plan. Obesity is more susceptible and often been associated with frequent ingestion of high energy food in high amount and high intake of sugars such as fermentable sugars such as sucrose, fructose, glucose, and maltose. Both diseases are may be genetically or due to hormonal imbalances. High energy sweeteners may causes caries in the teeth particularly susceptible to the children. Increased calorie intake associated with sugars and carbohydrates, especially when associated with physical inactivity, has been implicated in obesity. Fortunately, low calorie artificial and natural alternatives of sugars have been developed as alternatives to fermentable sugars and have shown promise in these health issues. Although there are only few artificial sweeteners (saccharin, aspartame, acesulfam potassium, sucralose, cyclamate that have been approved as food additives by the Food and Drug Administration and additional other low-caloric sweeteners (sugar alcohols, neotame, stevia, erythritol, xylitol, tagatose that have FDA-generally recognized as safe. Given the health impact of sugars and other carbohydrates, professionals should be aware of the marketed available low caloric sweeteners and both their benefits and potential risks.

  19. Desarrollo de la ingenieria basica de una planta industrial para extraccion con CO2 liquido. I. Extractores

    Directory of Open Access Journals (Sweden)

    GOLDENBERG Julio Fernando

    1998-01-01

    Full Text Available En base a los resultados obtenidos en una unidad piloto cuyo diseño, montaje y puesta en operación fueron realizados con la finalidad de poder producir el cambio de escala, se dio inicio al proyecto de una planta de producción con características modulares por su flexibilidad operativa en cuanto a capacidad de producción y tipo de materia prima. Se desarrolló la ingeniería conceptual, consistente en la definición de las bases de diseño; las diferentes etapas del proceso, la capacidad de producción a instalar, los rangos de trabajo de las variables operativas, el régimen, la especificación de los materiales de construcción, características de la carga, materiales auxiliares y tipo de instrumentación y control. La ingeniería básica, especificación de equipos y componentes auxiliares, para: alimentación de CO2, bombeo y presurización, acondicionamiento térmico, extracción, separación fluido/extracto, medida y control del caudal, temperatura y presión, se encuentra en una etapa avanzada de ejecución. Se ha comenzado con la ingeniería de detalle de extractores con diferente capacidad.

  20. Calores de Solución y Propiedades Termodinámicas Relacionadas: Un método Gráfico General de Cálculo

    Directory of Open Access Journals (Sweden)

    Alfredo Gómez O.

    2009-07-01

    Full Text Available Se presenta un método gráfico de cálculo con el cual es posible evaluar a partir de datos de calor de solución. diferentes propiedades termodinámicas de interés tales como: caloresres diferenciales de solución del soluto y del solvente. A HD,P 2 V ^ HOIF.I • calor de solución a dilución infinita A tH°; entalpias molares parciales relativas del soluto y del solvente. Lj y L,. y la entalpia molar aparente relativa, L^. El método está basado en la representación gráfica del calor integral de solución expresado por mol de soluto, A H||,fr.2 en función de la relación entre el número de moles de solvente y soluto, n^/nj. Cuando k>s datos experimentales de calor de solución son tomados hasta alta dilución, puede obtenerse con precisión el vak>r de A H°, con to cual el diagrama propuesto corresponde también a la representación gráfica de(^L2 en función de n^/nj. Se discute el significado f fsk» de las propiedades consideradas así como las relaciones existentes entre ellas. El diagrama propuesto presenta ventajas ya que además de su carácter más general, resulta más preciso y conveniente que k>s métodos particulares comúnmente empleados, especialmente en la evaluación de las propiedades citadas para el caso del soluto en soluciones muy diluidas. de(^L2 en función de n^/nj. Se discute el signifteado f fsk» de las propiedades conskJeradas asi como las relaciones existentes entre ellas. El diagrama propuesto presenta ventajéis ya que además de su caráctermás general, resulta más preciso y conveniente que k>s métodos particulares comúnmente empleados, especialmente en la evaluackin de las propiedades citadas para el caso del soluto en soluctones muy diluidas.

  1. Evaluación de una bomba de calor de Carnot operando en tiempo finito

    OpenAIRE

    José Alfredo Jiménez Bernal; Claudia del Carmen Gutiérrez Torres; Juan Gabriel Barbosa Saldaña; Pedro Quinto Diez

    2006-01-01

    El desarrollo de un nuevo modelo matemático para la evaluación del coeficiente de operación de una bomba de calor de Carnot que opera en tiempo finito (COPBCTF) se presenta en este trabajo. Se asume que el ciclo en el que opera esta bomba de calor es internamente reversible y externamente irreversible. Las irreversibilidades que ocurren debido a la duración finita de tiempo del ciclo se incluyen en los dos procesos de trasferencia de calor que forman parte del ciclo. Por otra parte, la contri...

  2. Isla de calor y ocupación espacial urbana en San Juan, Argentina: análisis evolutivo. Island heat effect and spatial urban occupancy in San Juan, Argentina: evolution analysis Ilha de calor e ocupação do espaço urbano em San Juán, Argentina: análise evolutiva

    Directory of Open Access Journals (Sweden)

    Mario Cúnsulo

    2011-06-01

    Full Text Available Resumen:En este artículo se presentan resultados finales de un proyecto de investigación bianual (2009-2010, denominado Variación histórica y espacial de la isla de calor urbana en zona árida, financiado por la Universidad Nacional de San Juan, Argentina. Su objetivo principal es determinar la progresiva modificación de la isla de calor urbana en un periodo de quince años (1995-2010 y la correlación de esta con la ocupación del área urbana del Gran San Juan (GSJ, localizada en la diagonal árida de Sudamérica. Los resultados obtenidos demuestran la interrelación entre la ocupación urbana y la espacialización de la isla de calor en la ciudad.Abstract:In this paper, final result of a bi-annual project (2009-2010 called Historic and spatial variation of the urban island heat effect in an arid zone –financed by Universidad Nacional de San Juan, Argentina –are presented. Its main aim is determining the progressive changing of urban island heat effect during a fifteen year period (1995-2010 and its correlationwith the occupancy of Great San Juan (GSJ urban area, located in South America’s arid diagonal. Results show the interrelationship between urban occupancy and the spread of island heat effect in the city.Resumo:Este artigo apresenta resultados finais do projeto de pesquisa de dois anos (2009-2010, chamado A variação histórica e espacial da ilha de calor urbana em uma zona árida, financiado pela Universidad Nacional de San Juán, Argentina. Seu principal objetivo é determinar a modificação progressiva da ilha de calor urbana por um período de 15 anos (1995-2010 e a correlação desta com a ocupação da área urbana da Gran San Juan (GSJ, localizada na diagonal árida de América do Sul. Os resultados obtidos demonstram a relação entre ocupação urbana e espacialização da ilha de calor na cidade.

  3. Modelación de la transferencia de calor y masa en el absorbedor de una máquina de refrigeración por absorción. // Heat and mass transference modeling in the absorvetor of an absorption cooling device.

    OpenAIRE

    C. Cisneros Ramírez

    2003-01-01

    En este artículo se dan las expresiones que caracterizan el comportamiento de la temperatura y del producto coeficienteglobal de traspaso de calor (U) por el área de traspaso de calor (A) , de un absorbedor de una máquina de refrigeración porabsorción que trabaja con la solución amoniaco – agua.Palabras claves: Modelación, absorbedores, refrigeración por absorción.______________________________________________________________________________Abstract.In this article the expressions that charac...

  4. ANÁLISIS DE EJERCICIOS DE ACONDICIONAMIENTO MUSCULAR EN SALAS DE MUSCULACIÓN. INCIDENCIA SOBRE EL RAQUIS EN EL PLANO SAGITAL

    Directory of Open Access Journals (Sweden)

    Pedro Ángel López Miñarro

    2005-01-01

    Full Text Available Se evaluó, mediante un inclinómetro ISOMED Unilevel, la curva dorsal y lumbar en bipedestación a 772 varones que realizan ejercicio en salas de musculación por motivos relacionados con la salud. También, se evaluó la cifosis dorsal en los ejercicios de press francés en polea, polea tras nuca, remo sentado con apoyo en tórax y curl de bíceps con barra; la lordosis lumbar en la extensión de tronco en banco romano, curl femoral, estiramiento del cuádriceps en bipedestación, polea al pecho, extensión de codo en bipedestación y curl de bíceps con barra; la cifosis total en los estiramientos de isquiosurales y adductores, remo en polea baja, remo con mancuerna, pájaro, incorporación del tronco, curl de bíceps con mancuerna, bíceps en banco predicador, elevación de cargas en bipedestación y en sedentación; y el protocolo de calentamiento y vuelta a la calma en 435 y 371 usuarios, respectivamente.

  5. MODELADO DE DINÁMICA DE FLUIDOS Y TRANSFERENCIA DE CALOR Y MASA EN PROCESOS AGROALIMENTARIOS POR MÉTODO DE VOLÚMENES FINITOS

    Directory of Open Access Journals (Sweden)

    NELSON O. MORAGA

    2011-01-01

    Full Text Available Se describe la transferencia de momento, calor y masa transitorio bi-dimensional en procesos agroalimentarios. Estos procesos son: la pre-cosecha y la deshidratación por aire caliente de frutas. La metodología incluye modelación matemática y simulación computacional para describir la convección y difusión de calor y masa conjugada que resulta de la interacción entre el alimento y el aire. El modelo matemático emplea las ecuaciones diferenciales parciales no lineales acopladas de continuidad, momento lineal, energía y materia. Se considera que las propiedades físicas de las frutas calculadas mediante correlaciones empíricas, varían con la temperatura y la concentración de humedad. El método de volúmenes finitos junto el algoritmo SIMPLE se utiliza para obtener los resultados de la variación en el tiempo de las distribuciones de velocidades (v, temperaturas (T y concentraciones de humedad (C para los procesos en estudio. Las propiedades termofísicas variables de los alimentos se obtuvieron a partir de modelos empíricos. Los resultados obtenidos incluyen distribuciones de las variables dependientes (v, T, C en el tiempo, los cuales se comparan con resultados experimentales y numéricos de la literatura especializada.

  6. Conjugate heat transfer analysis using the Calore and Fuego codes.

    Energy Technology Data Exchange (ETDEWEB)

    Francis, Nicholas Donald, Jr.

    2007-09-01

    Full coupling of the Calore and Fuego codes has been exercised in this report. This is done to allow solution of general conjugate heat transfer applications that require more than a fluid flow analysis with a very simple conduction region (solved using Fuego alone) or more than a complex conduction/radiation analysis using a simple Newton's law of cooling boundary condition (solved using Calore alone). Code coupling allows for solution of both complex fluid and solid regions, with or without thermal radiation, either participating or non-participating. A coupled physics model is developed to compare to data taken from a horizontal concentric cylinder arrangement using the Penlight heating apparatus located at the thermal test complex (TTC) at Sandia National Laboratories. The experimental set-up requires use of a conjugate heat transfer analysis including conduction, nonparticipating thermal radiation, and internal natural convection. The fluids domain in the model is complex and can be characterized by stagnant fluid regions, laminar circulation, a transition regime, and low-level turbulent regions, all in the same domain. Subsequently, the fluids region requires a refined mesh near the wall so that numerical resolution is achieved. Near the wall, buoyancy exhibits its strongest influence on turbulence (i.e., where turbulence conditions exist). Because low-Reynolds number effects are important in anisotropic natural convective flows of this type, the {ovr {nu}{sup 2}}-f turbulence model in Fuego is selected and compared to results of laminar flow only. Coupled code predictions are compared to temperature measurements made both in the solid regions and a fluid region. Turbulent and laminar flow predictions are nearly identical for both regions. Predicted temperatures in the solid regions compare well to data. The largest discrepancies occur at the bottom of the annulus. Predicted temperatures in the fluid region, for the most part, compare well to data. As

  7. DESHIDRATACION Y SOBREHIDRATACION VOLUNTARIAS DURANTE EL EJERCICIO EN EL CALOR: POSIBLES FACTORES RELACIONADOS

    Directory of Open Access Journals (Sweden)

    Andrea Solera Herrera

    2006-12-01

    Full Text Available Los efectos negativos de la deshidratación sobre la salud y el rendimiento han sido bien documentados. Recientemente, también se han documentado problemas por sobrehidratación. La presente investigación se hizo para estudiar los posibles factores que influyen sobre la ingesta voluntaria de líquido durante el ejercicio y determinar si existe relación entre el grado de deshidratación voluntaria y la creencia de que la ingesta de líquido provoca cólico. Para ello, se contó con 94 estudiantes universitarios jóvenes, varones, quienes se ejercitaron a un 60% de su FCmáx durante una hora, alternando cada 10 min. entre bicicleta estacionaria, subir y bajar un escalón, y una máquina simuladora de esquí. Esto se realizó en un laboratorio de ambiente controlado a 30úC, 70% humedad relativa. Durante el ejercicio se midió la ingesta voluntaria de una bebida deportiva, así como también las percepciones de calor ambiental, llenura estomacal, malestar gastrointestinal y palatabilidad de la bebida. Los sujetos fueron pesados desnudos y secos antes y después del ejercicio. Al final se les aplicó un cuestionario sobre la importancia de la hidratación, y sus creencias sobre el cólico. El equilibrio hídrico promedio fue de 0.14 ± 0.98% del peso corporal, con un rango entre -2.38% y 2.84%. La tasa de sudoración promedio fue de 1208.3 ± 381.7ml·h-1; y la ingesta de 1132 ± 610ml·h-1. Dos análisis de regresión múltiple determinaron que: (a los predictores más fuertes de la ingesta voluntaria de líquido fueron la importancia asignada a la hidratación durante el ejercicio (R2 = 0.13; p < 0.0005 y la percepción de llenura estomacal al minuto 25 (R2 = 0.08; p = 0.005; (b los predictores más fuertes del equilibrio hídrico fueron la ingesta voluntaria por kg de peso (R2 = 0.73; p < 0.0005, y la tasa de sudoración (R2 = 0.08; p = 0.006. No obstante, el equilibrio hídrico no estuvo asociado con ninguna de las percepciones, ni con las

  8. DETERMINACIÓN DEL CALOR DE FRAGUADO DE CEMENTO POR MICROCALORIMETRIA DE CONDUCCIÓN DE CALOR: Efecto de glucosa y sacarosa como aditivos retardantes

    Directory of Open Access Journals (Sweden)

    Liliana Giraldo G.

    2010-09-01

    Full Text Available Se determina el calor de fraguado del cemento Río Claro tipo III (Río Claro, Antioquia, Colombia por microcalorimetría de conducción de calor; así como también los efectos de la glucosa y de la sacarosa en el proceso de fraguado de este material. Al emplear 0,15 y 0,05% ( % en peso de estos aditivos en la preparación de las pastas, se observan retardos considerables en el fraguado de las mismas. Los aditivos también modifican el calor de fraguado: la pasta libre de estos presenta un valor de 38,03 J/g en tanto que la adición de glucosa y sacarosa producen valores menores, excepto en el caso de la sacarosa al 0,05% donde se observa un efecto térmico de 55.80 J/s,

  9. Diseño óptimo de un disipador de calor para luminaria LED mediante moderación modelación computacional

    Directory of Open Access Journals (Sweden)

    Daniel Cahue Díaz

    2014-01-01

    Full Text Available En el presente trabajo se desarrolla una selección de materiales y simulación térmica en el diseño de disipadores de calor para sistemas de iluminación de estado sólido (SSL mejor conocidos como luminarias LEDs. Se desarrolló un modelo matemático con la capacidad de predecir el comportamiento térmico de la luminaria cuando se encuentra en operación. El modelo matemático fue resuelto mediante un software de distribución libre el cual permite resolver ecuaciones diferenciales mediante el método de elemento finito. Los resultados obtenidos en el modelo matemático planteado fueron validados con los resultados obtenidos mediante experimentación usando imágenes termográficas.

  10. Use of caloric and noncaloric sweeteners in US consumer packaged foods, 2005-2009.

    Science.gov (United States)

    Ng, Shu Wen; Slining, Meghan M; Popkin, Barry M

    2012-11-01

    Our understanding of the use of caloric and noncaloric sweeteners in the US food supply is limited. This study uses full ingredient list and Nutrition Facts label data from Gladson Nutrition Database and nationally representative purchases of consumer packaged foods from Nielsen Homescan in 2005 through 2009 to understand the use of caloric sweeteners (including fruit juice concentrate) and noncaloric sweeteners in consumer packaged foods. Of the 85,451 uniquely formulated foods purchased during 2005 through 2009, 75% contain sweeteners (68% with caloric sweetener only, 1% with noncaloric sweetener only, 6% with both caloric and noncaloric sweeteners). Caloric sweetener are in >95% of cakes/cookies/pies, granola/protein/energy bars, ready-to-eat cereals, sweet snacks, and sugar-sweetened beverages. Noncaloric sweetener are in >33% of yogurts and sport/energy drinks, 42% of waters (plain or flavored), and most dietetic sweetened beverages. Across unique products, corn syrup is the most commonly listed sweetener, followed by sorghum, cane sugar, high-fructose corn syrup, and fruit juice concentrate. Also, 77% of all calories purchased in the United States in 2005-2009 contained caloric sweeteners and 3% contained noncaloric sweeteners, and 73% of the volume of foods purchased contained caloric sweetener and 15% contained noncaloric sweetener. Trends during this period suggest a shift toward the purchase of noncaloric sweetener-containing products. Our study poses a challenge toward monitoring sweetener consumption in the United States by discussing the need and options available to improve measures of caloric sweetener and noncaloric sweetener and additional requirements on Nutrition Facts labels on consumer packaged foods. PMID:23102182

  11. Fasting and Caloric Restriction in Cancer Prevention and Treatment.

    Science.gov (United States)

    Brandhorst, Sebastian; Longo, Valter D

    2016-01-01

    Cancer is the second leading cause of death in the USA and among the leading major diseases in the world. It is anticipated to continue to increase because of the growth of the aging population and prevalence of risk factors such as obesity, smoking, and/or poor dietary habits. Cancer treatment has remained relatively similar during the past 30 years with chemotherapy and/or radiotherapy in combination with surgery remaining the standard therapies although novel therapies are slowly replacing or complementing the standard ones. According to the American Cancer Society, the dietary recommendation for cancer patients receiving chemotherapy is to increase calorie and protein intake. In addition, there are no clear guidelines on the type of nutrition that could have a major impact on cancer incidence. Yet, various forms of reduced caloric intake such as calorie restriction (CR) or fasting demonstrate a wide range of beneficial effects able to help prevent malignancies and increase the efficacy of cancer therapies. Whereas chronic CR provides both beneficial and detrimental effects as well as major compliance challenges, periodic fasting (PF), fasting-mimicking diets (FMDs), and dietary restriction (DR) without a reduction in calories are emerging as interventions with the potential to be widely used to prevent and treat cancer. Here, we review preclinical and preliminary clinical studies on dietary restriction and fasting and their role in inducing cellular protection and chemotherapy resistance.

  12. Fasting and Caloric Restriction in Cancer Prevention and Treatment.

    Science.gov (United States)

    Brandhorst, Sebastian; Longo, Valter D

    2016-01-01

    Cancer is the second leading cause of death in the USA and among the leading major diseases in the world. It is anticipated to continue to increase because of the growth of the aging population and prevalence of risk factors such as obesity, smoking, and/or poor dietary habits. Cancer treatment has remained relatively similar during the past 30 years with chemotherapy and/or radiotherapy in combination with surgery remaining the standard therapies although novel therapies are slowly replacing or complementing the standard ones. According to the American Cancer Society, the dietary recommendation for cancer patients receiving chemotherapy is to increase calorie and protein intake. In addition, there are no clear guidelines on the type of nutrition that could have a major impact on cancer incidence. Yet, various forms of reduced caloric intake such as calorie restriction (CR) or fasting demonstrate a wide range of beneficial effects able to help prevent malignancies and increase the efficacy of cancer therapies. Whereas chronic CR provides both beneficial and detrimental effects as well as major compliance challenges, periodic fasting (PF), fasting-mimicking diets (FMDs), and dietary restriction (DR) without a reduction in calories are emerging as interventions with the potential to be widely used to prevent and treat cancer. Here, we review preclinical and preliminary clinical studies on dietary restriction and fasting and their role in inducing cellular protection and chemotherapy resistance. PMID:27557543

  13. Herdabilidade da necessidade de calor para a antese e brotação em pessegueiro

    Directory of Open Access Journals (Sweden)

    Citadin Idemir

    2003-01-01

    Full Text Available A herdabilidade da necessidade de calor para antese e brotação em pessegueiro [Prunus persica (L. Batsch] foi estudada em ramos de 16 cultivares e seleções de baixa, média e alta necessidade de calor e 11 progênies oriundas de hibridações entre elas. Os ramos foram submetidos, previamente, a 2 ºC por 500 horas para satisfazer a necessidade de frio. O valor estimado da herdabilidade média para a necessidade de calor em gemas florais foi de 45% e 57%, em 1999 e 2000, respectivamente. Para gemas vegetativas, o valor estimado foi de 30%, em 1999. 'BR-1', 'Barbosa', 'Chula', 'Chinoca' e 'Eldorado' transmitem melhor o caráter necessidade de calor para as progênies do que os demais genótipos estudados. Os registros observados suportam um modelo de herança quantitativa com genes de maior efeito para menor necessidade de calor. A seleção de indivíduos com maior necessidade de calor para floração tende a retardar a floração sem, contudo, retardar com a mesma intensidade a época de brotação.

  14. Caloric compensation for sugar-sweetened beverages in meals: A population-based study in Brazil.

    Science.gov (United States)

    Gombi-Vaca, Maria Fernanda; Sichieri, Rosely; Verly-Jr, Eliseu

    2016-03-01

    Sugar-sweetened beverage (SSB) consumption can cause positive energy balance, therefore leading to weight gain. A plausible biological mechanism to explain this association is through weak caloric compensation for liquid calories. However, there is an ongoing debate surrounding SSB calorie compensation. The body of evidence comes from a diversity of study designs and highly controlled settings assessing food and beverage intake. Our study aimed to test for caloric compensation of SSB in the free-living setting of daily meals. We analyzed two food records of participants (age 10 years or older) from the 2008-2009 National Dietary Survey (Brazil, N = 34,003). We used multilevel analyses to estimate the within-subject effects of SSB on food intake. Sugar-sweetened beverage calories were not compensated for when comparing daily energy intake over two days for each individual. When comparing meals, we found 42% of caloric compensation for breakfast, no caloric compensation for lunch and zero to 22% of caloric compensation for dinner, differing by household per capita income. In conclusion, SSB consumption contributed to higher energy intake due to weak caloric compensation. Discouraging the intake of SSB especially during lunch and dinner may help reduce excessive energy intake and lead to better weight management. PMID:26708263

  15. Caloric stimulation with near infrared radiation does not induce paradoxical nystagmus.

    Science.gov (United States)

    Walther, L E; Asenov, D R; Di Martino, E

    2011-04-01

    Near infrared radiation can be used for warm stimulation in caloric irrigation of the equilibrium organ. Aim of this study was to determine whether near infrared radiation offers effective stimulation of the vestibular organ, whether it is well tolerated by the patients and especially whether it is a viable alternative to warm air stimulation in patients with defects of the tympanic membrane and radical mastoid cavities. Patients with perforations of the tympanic membrane (n = 15) and with radical mastoid cavities (n = 13) were tested both with near infrared radiation and warm dry air. A caloric-induced nystagmus could be seen equally effectively and rapidly in all patients. Contrary to stimulation with warm dry air, no paradoxical nystagmus was observed following caloric irrigation with a warm stimulus (near infrared radiation). Results of a questionnaire showed excellent patient acceptance of near infrared stimulation with no arousal effects or unpleasant feeling. In conclusion, near infrared radiation proved to be an alternative method of caloric irrigation to warm dry air in patients with tympanic membrane defects and radical mastoid cavities. Near infrared radiation is pleasant, quick, contact free, sterile and quiet. With this method an effective caloric warm stimulus is available. If near infrared radiation is used for caloric stimulus no evaporative heat loss occurs.

  16. Computational program to design heat pumps by compression (ciclo 1.0); Programa computacional para diseno de bombas de calor por compresion (ciclo 1.0)

    Energy Technology Data Exchange (ETDEWEB)

    De Alba Rosano, Mauricio [CIE, UNAM, Temixco, Morelos (Mexico)

    2000-07-01

    A new computational program has been developed in order to design single stage compression heat pumps. This software, named CICLO 1.0 allows the design of water-water, water-air, air-water and air-air heat pumps, for industrial and residential applications. CICLO 1.0 simulates three types of compressors: reciprocating, screw and scroll. Also has a data base created with REFPROP software which includes eleven refrigerants. The condenser and evaporator simulation includes global conductance (UA) determination, and when one or both are shell and tube's type, this software shows the even number of tube passes by shell. The software determines the best compressor and refrigerant setup taking the COP as a parameter; in order to obtain this, is necessary to know the inlet/outlet conditions of the fluid to be heated, the inlet conditions of the fluid that gives heat, and the electric motor efficiency that drives the compressor. The afforded results by CICLO 1.0 are: operation conditions from compression cycle, that means, pressures and temperatures at the inlet/outlet from every heat pump component are determined: as well as refrigerant mass flux, COP, power required by compressor, volumetric and isentropic efficiencies, heat exchangers global conductance and more data. CICLO 1.0 has been executed with heat pump data that nowadays are operating, and the results from the simulation have been very similar each other with data reported from operational facilities. [Spanish] Se ha desarrollado un nuevo programa computacional para el diseno de bombas de calor por compresion de vapor de una sola etapa. Este programa, CICLO 1.0, permite el diseno de bombas de calor de tipo: agua-agua, agua-aire, aire-agua y aire-aire, que se utilicen para aplicaciones industriales, de servicios y residenciales. CICLO 1.0 simula tres tipos de compresores: reciprocante, de tornillo y scroll: cuenta con una base de datos de refrigerantes creada con el programa REFPROP la cual incluye once

  17. Cardioprotective Signature of Short-Term Caloric Restriction.

    Directory of Open Access Journals (Sweden)

    Hossein Noyan

    Full Text Available To understand the molecular pathways underlying the cardiac preconditioning effect of short-term caloric restriction (CR.Lifelong CR has been suggested to reduce the incidence of cardiovascular disease through a variety of mechanisms. However, prolonged adherence to a CR life-style is difficult. Here we reveal the pathways that are modulated by short-term CR, which are associated with protection of the mouse heart from ischemia.Male 10-12 wk old C57bl/6 mice were randomly assigned to an ad libitum (AL diet with free access to regular chow, or CR, receiving 30% less food for 7 days (d, prior to myocardial infarction (MI via permanent coronary ligation. At d8, the left ventricles (LV of AL and CR mice were collected for Western blot, mRNA and microRNA (miR analyses to identify cardioprotective gene expression signatures. In separate groups, infarct size, cardiac hemodynamics and protein abundance of caspase 3 was measured at d2 post-MI.This short-term model of CR was associated with cardio-protection, as evidenced by decreased infarct size (18.5±2.4% vs. 26.6±1.7%, N=10/group; P=0.01. mRNA and miR profiles pre-MI (N=5/group identified genes modulated by short-term CR to be associated with circadian clock, oxidative stress, immune function, apoptosis, metabolism, angiogenesis, cytoskeleton and extracellular matrix (ECM. Western blots pre-MI revealed CR-associated increases in phosphorylated Akt and GSK3ß, reduced levels of phosphorylated AMPK and mitochondrial related proteins PGC-1α, cytochrome C and cyclooxygenase (COX IV, with no differences in the levels of phosphorylated eNOS or MAPK (ERK1/2; p38. CR regimen was also associated with reduced protein abundance of cleaved caspase 3 in the infarcted heart and improved cardiac function.

  18. Revisión del cálculo del coeficiente de traspaso de calor en ebullición en minicanales y microcanales//Review of heat transfer coefficient calculation in boiling in minichannels and microchannels

    Directory of Open Access Journals (Sweden)

    César Arnaldo Cisneros‐Ramírez

    2014-05-01

    Full Text Available La necesidad de disipar altas densidades de flujo de calor ha llevado a los investigadores y diseñadores a emplear el cambio de fase como mecanismo para lograr tal objetivo y con ello lograr equipos intercambiadores de calor más compactos. En el presente trabajo se realizó un estudio de la bibliográfica sobre la ebullición en minicanales y microcanales. Para ello se consultaron bibliografíasque datan desde los años 90 hasta la actualidad, con lo cual se revelaron los principales parámetros o tópicos que caracterizan a este proceso en minicanales y microcanales. Es así que se abordan los términos minicanales y microcanales, ebullición en flujo forzado y regímenes (mapa de flujo.Además se presenta un resumen de las ecuaciones para la determinación del coeficiente de traspaso de calor en régimen bifásico (hdf.Palabras claves: ebullición, microcanales, minicanales, coeficiente de traspaso de calor.____________________________________________________________________________AbstractThe necessity of transfer high heat flux had led to researchers and designers to use the change of phase in order to get this objective. In this work was made a review in more of seventy sources of information dating since 90´s up to the present, where were revealed the main parameters that characterize the boiling process in minichanels-microchannels. It deals with terms minimicrochannels,flow boiling and flow pattern map. Also, it is presented a summary of equations used for calculate the two-phase heat transfer coefficient.Key words: boiling, minichannels, microchannels, heat transfer coefficient.

  19. 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

  20. Validation of a smooth configuration surface for compact heat exchangers using a numerical method//Validación de la superficie de un intercambiador de calor compacto en configuración lisa utilizando un método numérico

    Directory of Open Access Journals (Sweden)

    José‐L. Leiro‐Garrido

    2014-08-01

    Full Text Available This work determines the thermo hydraulics behavior of smooth configuration surface for a compact heat exchanger by means of numerical simulation. The objective is to use the results as baseline for research in the enhancement of heat transfer and drag reduction, directed to reduce the energy consumption and diminish the environmental impact. The fin tube heat exchanger models described.The constraints used in the implementation of the equation solver are announced. The average heat transfer coefficient and pressure drop obtained from numerical simulation are compare to experimental results presented in literature for models with the same dimensions and configuration. A good agreement between numerical and experimental results is reached. Local mechanisms responsible for the heat transfer and pressure drop are detailed. The study is conducted inside thelaminar regime for frontal velocities ranging between 0.5 and 6 m/s.Key words: compact heat exchanger, heat transfer coefficient, numerical simulation, pressure drop.______________________________________________________________________________ResumenEste trabajo determina el comportamiento termo hidráulico de una superficie perteneciente a un intercambiador de calor compacto en configuración lisa utilizando un método de simulación numérica. El objetivo es caracterizar la superficie para poder utilizarla como una referencia en las comparaciones con superficies de intercambio de calor intensificadas. Los datos obtenidos seutilizaran en la determinación de los valores relativos de intensificación de la transferencia de calor y el arrastre intentando reducir el consumo energético y su impacto ambiental. Se describe el modelo de intercambiador de calor con tubos aletados. Los resultados numéricos obtenidos presentan unbuen ajuste con los valores experimentales. Los resultados del coeficiente de transferencia de calor global y la caída de presión son explicados a partir de las

  1. Bases moleculares del post-acondicionamiento en corazones reperfundidos : papel de la mitocondria, con énfasis en la participación del poro de la transición de la permeabilidad mitocondrial /

    OpenAIRE

    Correa Segura, Francisco sustentante.

    2009-01-01

     tesis que para obtener el grado de Doctor en Ciencias Biomédicas, presenta Francisco Correa Segura ; asesor Ana Cecilia Zazueta Medizábal. 100, [56] páginas : ilustraciones. Doctorado en Ciencias Biomédicas UNAM, Facultad de Medicina, 2009

  2. Preparatory of X zeolite (faujasite) with surfactant hexa decyl trimethyl ammonium bromide (HMDTA) for adsorption of organic compounds; Acondicionamiento de zeolita X (faujasita) con surfactante bromuro de hexa decil trimetil amonio (HDTMA) para adsorcion de compuestos organicos

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez R, V

    2003-07-01

    The water represents one of the most valuable natural resources for the alive beings, since it is the essential component of the alive matter. Also, it is fundamental part of our planet, since is an indispensable element for the integral development of the same one. The demographic growth, the human being's activities and the industrial growth, he/she brings as consequence an increase in the use of the water and the generation of residual waters that successively contaminate the hydrological basins, becoming an environmental problem urgent. The contamination of the water with compound such as phenol and benzene, it is a problem that it requires the search of solutions, since it is of compound not very biodegradable, able to accumulate through the food chains and very toxic to the alive beings that they enter in contact with them (Tolgyessy, 1993). In the human beings it can take place damages in liver and kidney, the Agency of Protection to the Atmosphere of the United States (EPA) it considers that the exhibition for benzene is related with the leukemia, it is also considered as a carcinogen substance. Of the methods that are used for the treatment of polluted waters, it highlights the use of adsorber and one of them is the zeolites, since they are broadly used in those separation processes. The zeolites is crystalline aluminosilicates, they are characterized for to have a big superficial area and for their great capacity of exchange cationic, due to it the process of adsorption depends on these two characteristics, since to the modified being superficially for surfactants cationic it originates an enriched layer of carbon organic, which has the capacity to remove pollutants of the water. The present work outlines as objective to carry out the superficial modification of zeolite X using hexa decyl trimethyl ammonium bromide (HMDTA-Br) to different concentrations, with the purpose of making it useful in the removal of pollutants organic, present in watery solution. The results of this investigation work indicate that the superficial modification of the zeolite X with HMDTA-Br to the four used concentrations 29, 58, 116 and 174 mmol L was possible, and it is demonstrated by the results of electronic microscopy of sweeping and for the decrease of the content of sodium carried out by Neutron activation analysis. In relation to the removal tests, it was found that the zeolite modified X with the biggest surfactant concentration it presents the highest phenol percentage removed, being this of 38% for a time of contact of 3 hours. In accordance with the results of removal of benzene is observed that the zeolite X removes 56%, but the modified zeolite removes a bigger quantity of until 90%, said percentage varies with regard to the time of contact. Therefore the modification of the zeolite X is favorable for the removal of the benzene. (Author)

  3. Effects of caloric vestibular stimulation on serotoninergic system in the media vestibular nuclei of guinea pigs

    Institute of Scientific and Technical Information of China (English)

    MA Fu-rong; LIU Jun-xiu; LI Xue-pei; MAO Jian-jun; ZHANG Qun-dan; JIA Hong-bo; MAO Lan-quan; ZHAO Rui

    2007-01-01

    Background Anatomic and electrophysiological studies have revealed that the neurons located in the media vestibular nuclei (MVN) receive most of the sensory vestibular input coming from the ipsilateral labyrinth and the responses of MVN neurons to caloric stimulation directly reflect changes in primary vestibular afferent activity. The aim of this study was to clarify the intrinsic characteristics of serotonin (5-hydroxytryptamine, 5-HT) release in the MVN during the period of vertigo induced by caloric stimulation.Methods We used an in vivo microdialysis technique to examine the effects of caloric stimulation on the serotoninergic system in MVN. Twenty four guinea pigs were randomly divided into the groups of irrigation of the ear canal with hot water (n=6), ice water (n=6) and 37℃ water (n=4), and the groups of irrigation of the auricle with hot water (n=4) and ice water (n=4), according to different caloric vestibular stimulation. We examined the animal's caloric nystagmus with a two-channel electronystagmographic recorder (ENG), and meanwhile examine serotonin (5-hydroxytryptamine, 5-HT) level in the MVN with microdialysis technique after caloric stimulation. Results In the caloric test the hot water (44℃) irrigation of the right external auditory canal induced horizontal nystagmus towards the right side lasting about 60 seconds and the ice water irrigation of the right external auditory canal induced it towards the left side lasting for about 90 seconds. No nystagmus was induced by 37℃ water irrigation of the external ear canal. Therefore, it was used as a negative control stimulation to the middle ear. The MVN 5-HT levels significantly increased in the first 5-minute collecting interval and increased to 254% and 189% of the control group in the second collecting interval in response to caloric vestibular stimulation with ice water and hot water respectively. The serotonin release was not distinctly changed by the irrigation of the auricle with ice water

  4. A Biomechanical Model of the Inner Ear: Numerical Simulation of the Caloric Test

    Directory of Open Access Journals (Sweden)

    Shuang Shen

    2013-01-01

    Full Text Available Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. The anterior canal cupula began to receive the caloric stimuli about 20 s after the HC cupula, and it maximally deflected to the canal side by 0.55 μm. The posterior canal cupula did not receive caloric stimuli until approximately 40 s after the HC cupula, and it maximally deflected to the canal side by 0.34 μm. Although the endolymph flow and the cupular deformation change with respect to the head position during the test, the supine test ensures the maximal caloric response in the HC, but no substantial improvement for the responses of the two vertical canals was observed. In conclusion, while the usual supine test is the optimum test for evaluating the functions of the inner ear, more irrigation time is needed in order to effectively clinically examine the vertical canals.

  5. A biomechanical model of the inner ear: numerical simulation of the caloric test.

    Science.gov (United States)

    Shen, Shuang; Liu, Yingxi; Sun, Xiuzhen; Zhao, Wei; Su, Yingfeng; Yu, Shen; Liu, Wenlong

    2013-01-01

    Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC) cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. The anterior canal cupula began to receive the caloric stimuli about 20 s after the HC cupula, and it maximally deflected to the canal side by 0.55 μm. The posterior canal cupula did not receive caloric stimuli until approximately 40 s after the HC cupula, and it maximally deflected to the canal side by 0.34 μm. Although the endolymph flow and the cupular deformation change with respect to the head position during the test, the supine test ensures the maximal caloric response in the HC, but no substantial improvement for the responses of the two vertical canals was observed. In conclusion, while the usual supine test is the optimum test for evaluating the functions of the inner ear, more irrigation time is needed in order to effectively clinically examine the vertical canals.

  6. Construcción de un Calorímetro para la Determinación de Entalpías de Inmersión Construction of a Calorimeter for the Determination of Immersion Enthalpies

    Directory of Open Access Journals (Sweden)

    Vanessa García

    2007-01-01

    Full Text Available Se presenta la construcción de un calorímetro de conducción de calor y se muestra en detalle cada uno de sus elementos constituyentes, con énfasis en el sistema que se usa para detectar el flujo de calor. El calorímetro fue eléctrica y químicamente calibrado y se determinó la entalpía de inmersión de carbones activados en soluciones acuosas de compuestos con capacidad de ionizarse, tales como fenol y nitrato de plomo. En el primer caso la entalpía de inmersión promedio resultó de 48.9 ± 1.4 Jg-1 para un carbón activado de área superficial 950 m²g-1. En el segundo caso, las entalpías de inmersión variaron entre 5 y 65 Jg-1 para distintas soluciones acuosas de Pb2+ y para un carbón activado con área superficial de 585 m²g-1. Se concluye que el calorímetro construido tiene características de estabilidad de línea base, constante de calibración y sensibilidad, adecuadas para las determinaciones de entalpías de inmersión de sólidos porosos en líquidos.The construction and use of a heat conduction calorimeter is presented, given specific details about every component, focusing in the system used to sensor the heat flow. The calorimeter was electrically and chemically calibrated and was used for determining of the immersion enthalpy of activated carbons in aqueous solutions of compounds with capacity of ionization, such as phenol and lead nitrate. In the first case, the immersion enthalpy of an activated carbon with superficial area of 950 m²g-1 gave an average value of 48.9 ± 1.4 Jg-1. In the second case, Pb2+ aqueous solutions and an activated carbon with superficial area of 585 m²g-1, the immersion enthalpies ranged between 5 and 65 Jg-1. It is concluded that the constructed calorimeter has characteristic of base line stability, calibration constant and sensibility, appropriate to determine immersion enthalpies of porous solids in liquids.

  7. Normal physical activity obliterates the deleterious effects of high-caloric intake

    DEFF Research Database (Denmark)

    Krogh-Madsen, Rikke; Pedersen, Maria; Solomon, Thomas;

    2013-01-01

    A high-caloric intake combined with a sedentary lifestyle is an important player in the development of type 2 diabetes mellitus (T2DM). The present study was undertaken to examine if the level of physical activity has impact on the metabolic effects of a high-caloric (+2,000 kcal/day) intake...... visceral fat compared to the active group. Following the two-week period, the inactive group also experienced a poorer glycaemic control, increased endogenous glucose production, decreased hepatic insulin extraction, increased baseline plasma levels of total cholesterol and LDL, and a decreased cognitive....... Therefore, healthy individuals on a high caloric intake were randomized to either 10,000 or 1,500 steps per day for 14 days. Step-number, total energy expenditure, dietary records, neuropsychological tests, maximal oxygen uptake (VO2max), whole body dual-energy X-ray absorptiometry (DXA)- and abdominal...

  8. Determinación del calor de fraguado de cemento por icrocalorimetría

    Directory of Open Access Journals (Sweden)

    Liliana Girlado G.

    2010-07-01

    Full Text Available Se determina el calor de fraguado del cemento Río Claro tipo III (Río Claro, Antioquia, Colombia por microcalorimetría de conducción de calor; así como también los efectos de la glucosa y de la sacarosa en el proceso de fraguado de este material. Al emplear 0,15 y 0,05% ( % en peso de estos aditivos en la preparación de las pastas, se observan retardos considerables en el fraguado de las mismas. Los aditivos también modifican el calor de fraguado: la pasta libre de estos presenta un valor de 38,03 J/g en tanto que la adición de glucosa y sacarosa producen valores menores, excepto en el caso de la sacarosa al 0,05% donde se observa un efecto térmico de 55.80 J/s,

  9. Caloric restriction and exercise “mimetics”: ready for prime time?

    Science.gov (United States)

    Handschin, Christoph

    2016-01-01

    Exercise and diet are powerful interventions to prevent and ameliorate various pathologies. The development of pharmacological agents that confer exercise- or caloric restriction-like phenotypic effects is thus an appealing therapeutic strategy in diseases or even when used as life-style and longevity drugs. Such so-called exercise or caloric restriction “mimetics” have so far mostly been described in pre-clinical, experimental settings with limited translation into humans. Interestingly, many of these compounds activate related signaling pathways, most often postulated to act on the common downstream effector peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) in skeletal muscle. In this review, resveratrol and other exercise- and caloric restriction “mimetics” are discussed with a special focus on feasibility, chances and limitations of using such compounds in patients as well as in healthy individuals. PMID:26658171

  10. Determinaciones termogravimétricas y de calor específico de un concentrado comercial de ulexita, entre temperatura ambiente y 1.000 ºC

    Directory of Open Access Journals (Sweden)

    Flores, H. R.

    2006-12-01

    Full Text Available The important amount of hydration water in the ulexite (NaCaB5O9.8H2O, allows using calcination methods to increase its B2O3 content. This paper analyses the thermal decomposition reaction of a preconcentrated ulexite through weight loss measurements, which occur during the heating of samples until 1000 ºC. Determinations of heat content at each temperature were made using an isoperibol calorimeter. The mean specific heat was calculated from these values, and its dependence on temperature was determined. The maximum weight loss was about 32.5 % and the specific heat obtained was 1,13 kJ/kgºC for solid samples and 1,38 kJ/kgºC for fluid samples.The results are useful for the design of the industrial process, in order to determine the thermal requirements for heating calcined ulexite, and to obtain smelted ulexite.

    El elevado contenido de agua de hidratación de la ulexita (NaCaB5O9.8H2O permite utilizar la calcinación como método de concentración. En este trabajo se analiza la reacción de descomposición térmica de un preconcentrado de ulexita a través de determinaciones de la pérdida de peso ocurrida durante el calentamiento de la muestra hasta 1000 ºC. Por otra parte, se ha determinado el valor del calor sensible a cada temperatura ensayada mediante un calorímetro tipo isoperibol y se ha calculado el calor específico medio de la muestra calcinada, así como su variación con la temperatura. Se obtuvieron pérdidas de peso de 32,5 % y valores del calor específico de 1,13 kJ/kgºC para muestras sólidas y 1,38 kJ/kgºC para las fluidas. Los resultados son de utilidad para el diseño del proceso industrial, para la determinación del requerimiento térmico para el calentamiento de ulexita calcinada y para la obtención de una frita.

  11. Moderate exercise training and chronic caloric restriction modulate redox status in rat hippocampus.

    Science.gov (United States)

    Santin, Katiane; da Rocha, Ricardo Fagundes; Cechetti, Fernanda; Quincozes-Santos, André; de Souza, Daniela Fraga; Nardin, Patrícia; Rodrigues, Letícia; Leite, Marina Concli; Moreira, José Cláudio Fonseca; Salbego, Christianne Gazzana; Gonçalves, Carlos Alberto

    2011-11-01

    Physical activity has been related to antioxidant adaptations, which is associated with health benefits, including those to the nervous system. Additionally, available data suggest exercise and a caloric restriction regimen may reduce both the incidence and severity of neurological disorders. Therefore, our aim was to compare hippocampal redox status and glial parameters among sedentary, trained, caloric-restricted sedentary and caloric-restricted trained rats. Forty male adult rats were divided into 4 groups: ad libitum-fed sedentary (AS), ad libitum-fed exercise training (AE), calorie-restricted sedentary (RS) and calorie-restricted exercise training (RE). The caloric restriction (decrease of 30% in food intake) and exercise training (moderate in a treadmill) were carried out for 3 months. Thereafter hippocampus was surgically removed, and then redox and glial parameters were assessed. Increases in reduced glutathione (GSH) levels and total antioxidant reactivity (TAR) were observed in AE, RS and RE. The nitrite/nitrate levels decreased only in RE. We found a decrease in carbonyl content in AE, RS and RE, while no modifications were detected in thiobarbituric acid reactive substances (TBARS). Total reactive antioxidant potential (TRAP), superoxide dismutase (SOD) activity, S100B and glial fibrilary acid protein (GFAP) content did not change, but caloric restriction was able to increase glutamine synthetase (GS) activity in RS and glutamate uptake in RS and RE. Exercise training, caloric restriction and both combined can decrease oxidative damage in the hippocampus, possibly involving modulation of astroglial function, and could be used as a strategy for the prevention of neurodegenerative diseases. PMID:21974860

  12. Influence of personal and lesson factors on caloric expenditure in physical education

    Institute of Scientific and Technical Information of China (English)

    Ang; Chen; Haichun; Sun; Xihe; Zhu; Catherine; D.Ennis

    2012-01-01

    <正>Background:Increasing caloric expenditure in physical education is considered an effective school-based approach to addressing the child obesity epidemic.This study was designed to determine synergistic influences of student characteristics and lesson factors on caloric expenditure in elementary and middle school physical education. Methods:The study used a multi-level design.Level-1 factors included personal characteristics:age,gender,and body mass index.Level-2 factors included lesson length,content,and school level.Based on the Center for Disease Control and Prevention age—gender adjusted growth chart,students in 87 classes from 14 elementary and 15 middle schools were pre-screened into "Overweight","Healthy weight",or "Thin" groups.One boy and one girl were randomly selected from each group in each class as data providers(264 elementary and 294 middle school students).Caloric expenditure was measured in 243 physical education lessons using accelerometers. Results:Analysis of variance revealed and hierarchical linear modeling confirmed separate age by body mass index,age by gender,and content by lesson—length interaction effects,suggesting that the personal and lesson factors influenced caloric expenditure independently.Older male and heavier students burned more calories in all lessons.Students burned more calories in 45—60 min sport skill or fitness lessons than in shorter (30 min) or longer(75—90 min) game or multi-activity lessons. Conclusions:The hypothesized cross-level interaction was not observed in the data.Caloric expenditure can be optimized in 45—60 min sport skill or fitness development lessons.It can be recommended that schools adopt 45—60 min lesson length and provide skill and fitness development tasks in physical education to maximize caloric expenditure.

  13. Caloric Intake From Fast Food Among Children and Adolescents in the United States, 2011-2012.

    Science.gov (United States)

    Vikraman, Sundeep; Fryar, Cheryl D; Ogden, Cynthia L

    2015-09-01

    Consumption of fast food has been linked to weight gain in adults (1). Fast food has also been associated with higher caloric intake and poorer diet quality in children and adolescents (2). From 1994 through 2006, caloric intake from fast food increased from 10% to 13% among children aged 2-18 years (3). This report presents the most recent data on the percentage of calories consumed from fast food among U.S. children by sex, age group, race and Hispanic origin, poverty status, and weight status. PMID:26375457

  14. Absence of rotation perception during warm water caloric irrigation in some seniors with postural instability

    Directory of Open Access Journals (Sweden)

    Elodie eChiarovano

    2016-01-01

    Full Text Available Falls in seniors are a major public health problem. Falls lead to fear of falling, reduced mobility and decreased quality of life. Vestibular dysfunction is one of the fall risk factors. The relationship between objective measures of vestibular responses and age has been studied. However, the effects of age on vestibular perception during caloric stimulation have not been studied.Twenty senior subjects were included in the study separated in two groups: 10 seniors reporting postural instability (PI and exhibiting absence of vestibular perception when they tested with caloric stimulation and 10 sex and age-matched seniors with no such problems (controls. We assessed vestibular perception on a binary rating scale during the warm irrigation of the caloric test. The function of the various vestibular receptors was assessed using video-head impulse test (vHIT, caloric tests, and cervical and ocular VEMPs. The Equitest was used to evaluate balance. No horizontal canal dysfunction assessed using both caloric test and vHIT was detected in either group. No significant difference was detected between PI and control groups for the peak SPV of caloric induced ocular nystagmus or for the HVOR gain. All of the controls perceived rotation when the maximal SPV during warm irrigation was equal to or greater than 15°/s. None of the subjects in the PI group perceived rotation even while the peak SPV exceeded 15°/s, providing objective evidence of normal peripheral horizontal canal function. All of the PI group had abnormal Equitest results, particularly in the two last conditions.These investigations show for the first time that vestibular perception can be absent during a caloric test despite normal horizontal canal function. We call this dissociation vestibular neglect. Patients with poor vestibular perception may not be aware of postural perturbations and so will not correct for them. Thus, falls in the elderly may result, amongst other factors, from a

  15. Absence of Rotation Perception during Warm Water Caloric Irrigation in Some Seniors with Postural Instability.

    Science.gov (United States)

    Chiarovano, Elodie; Vidal, Pierre-Paul; Magnani, Christophe; Lamas, Georges; Curthoys, Ian S; de Waele, Catherine

    2016-01-01

    Falls in seniors are a major public health problem. Falls lead to fear of falling, reduced mobility, and decreased quality of life. Vestibular dysfunction is one of the fall risk factors. The relationship between objective measures of vestibular responses and age has been studied. However, the effects of age on vestibular perception during caloric stimulation have not been studied. Twenty senior subjects were included in the study, and separated in two groups: 10 seniors reporting postural instability (PI) and exhibiting absence of vestibular perception when they tested with caloric stimulation and 10 sex- and age-matched seniors with no such problems (controls). We assessed vestibular perception on a binary rating scale during the warm irrigation of the caloric test. The function of the various vestibular receptors was assessed using video head impulse test (vHIT), caloric tests, and cervical and ocular vestibular-evoked myogenic potentials. The Equitest was used to evaluate balance. No horizontal canal dysfunction assessed using both caloric test and vHIT was detected in either group. No significant difference was detected between PI and control groups for the peak SPV of caloric-induced ocular nystagmus or for the HVOR gain. All the controls perceived rotation when the maximal SPV during warm irrigation was equal to or ≥15°/s. None of the subjects in the PI group perceived rotation even while the peak SPV exceeded 15°/s, providing objective evidence of normal peripheral horizontal canal function. All the PI group had abnormal Equitest results, particularly in the two last conditions. These investigations show for the first time that vestibular perception can be absent during a caloric test despite normal horizontal canal function. We call this as dissociation vestibular neglect. Patients with poor vestibular perception may not be aware of postural perturbations and so will not correct for them. Thus, falls in the elderly may result, among other factors, from

  16. The behaviour of constrained caloric curves as ultimate signature of a phase transition for hot nuclei

    CERN Document Server

    Borderie, B; Rivet, M F; Raduta, Ad R; Bonnet, E; Bougault, R; Chbihi, A; Galichet, E; Guinet, D; Lautesse, Ph; Neindre, N Le; Lopez, O; Parlog, M; Rosato, E; Roy, R; Spadaccini, G; Vient, E; Vigilante, M

    2012-01-01

    Simulations based on experimental data obtained from multifragmenting quasifused nuclei produced in central 129Xe + natSn collisions have been used to deduce event by event freeze-out properties on the thermal excitation energy range 4-12 AMeV. From these properties and temperatures deduced from proton transverse momentum fluctuations constrained caloric curves have been built. At constant average volumes caloric curves exhibit a monotonous behaviour whereas for constrained pressures a backbending is observed. Such results support the existence of a first order phase transition for hot nuclei.

  17. ILHA DE CALOR: REFLEXÕES ACERCA DE UM CONCEITO (Heat island: reflections on a concept)

    OpenAIRE

    FIALHO, Edson Soares

    2012-01-01

    O conceito de ilha de calor está relacionado às atividades humanas sobre a superfície e sua repercussão na troposfera inferior, ainda assim, não está claro, na literatura, em que momento ou qual diferença de temperatura do ar se pode atestar a existência do fenômeno em questão. Além dessa vulnerabilidade conceitual, hoje existem novas possibilidades de identificar a ilha de calor, tais como: registradores contínuos de temperatura do ar e umidade relativa (data-loggers), balões meteorológicos ...

  18. Changes of endolymphatic pressure in the semicircular canal of pigeon by caloric stimulation

    Science.gov (United States)

    Wada, Y.; Suzuki, H.; Watanabe, S.

    1994-08-01

    It gets into difficult to explain the mechanism of caloric nystagmus only by convection theory from results of microgravity experiments. One of the other theories is an occurrence of a relative volume change due to a temperature change. Since the volume change must lead to a pressure change after caloric stimulation, we tried to measure the ampulla pressure of the horizontal semicircular canal in pigeons (Columba livia) using an improved servo micropipette system. The main result was that the ampulla pressure increased by cooling and decreased by heating. The changes of the ampulla pressure depended on the temperature change but were not influenced by the pigeon's head position.

  19. La función de las edificaciones en el acondicionamiento, contención y organización de actividades en el sistema Kirón

    Directory of Open Access Journals (Sweden)

    Curiel Carías, Ernesto C.

    2006-04-01

    a solventar el divorcio existente entre los esquemas organizativos de los sistemas naturales y el de los artificiales. Apoyándose en la extensa información científica disponible acerca de los sistemas vivos (SV, se infieren en el presente trabajo algunos de los atributos que deben integrar los conceptos relativos a las funciones de acondicionamiento, contención y organización de actividades de aquellas edificaciones estrechamente vinculadas a los SV. Para ello se expone el concepto del Sistema Kiron (SK –elemento que integra el actual desarrollo de la tesis Doctoral del autor– consistente en un nuevo nivel jerárquico de organización, semi-artificial, constituido por tres subsistemas (el ecosistema, el cuerpo humano en tanto organismo o biosistema y la edificación o sistema artificial cuya función es, precisamente, contribuir a disolver la dicotomía entre la lógica organizativa de los sistemas naturales y la de los artificiales. Es en el seno del SK donde se modifican los conceptos de tales funciones. Los límites del Sistema Kiron vienen a constituir el nuevo continente dentro del cual la edificación o sistema artificial (SA organiza y es organizada, contiene y es contenida, y donde su función de acondicionamiento ambiental es conceptuada como un transductor que compatibiliza las entradas y salidas entre el subsistema SE y el subsistema SB, posibilitando la constitución de una red híbrida de elementos naturales y artificiales, cuyo objetivo común es alcanzar su propia estabilidad dinámica y la del SK al que pertenecen.

  20. Prenatal Caloric Intake and the Development of Academic Achievement among U.S. Children from Ages 5 to 14

    Science.gov (United States)

    Connolly, Eric J.; Beaver, Kevin M.

    2015-01-01

    Few studies have examined the relation between maternal caloric intake during pregnancy and growth in child academic achievement while controlling for important confounding influences. Using data from the National Longitudinal Survey of Youth, the current study examined the effects of reduced prenatal caloric intake on growth in scores on the…

  1. Effect of Replacing Sugar with Non-Caloric Sweeteners in Beverages on the Reward Value after Repeated Exposure

    NARCIS (Netherlands)

    Griffioen-Roose, S.; Smeets, P.A.M.; Weijzen, P.L.G.; Rijn, van I.; Bosch, van den I.; Graaf, de C.

    2013-01-01

    Background: The reward value of food is partly dependent on learned associations. It is not yet known whether replacing sugar with non-caloric sweeteners in food is affecting long-term acceptance. Objective: To determine the effect of replacing sugar with non-caloric sweeteners in a nutrient-empty d

  2. RELACION ENTRE LA TERMOESTABILIDAD DE LA MEMBRANA, LA VIABILIDAD CELULAR Y LOS CRITERIOS DE TOLERANCIA EN LA EVALUACIÓN DE LA TOLERANCIA AL CALOR EN TOMATE (Solanum L. sección Lycopersicon subsección Lycopersicon

    Directory of Open Access Journals (Sweden)

    Marilyn Florido Bacallao

    2011-01-01

    Full Text Available El presente trabajo se desarrolló con el objetivo deconocer si existe variabilidad en cuanto a tolerancia al calor enuna muestra representativa del germoplasma de tomate (Solanum L. sección Lycopersicon subsección Lycopersicon conservadoex situ en las colecciones cubanas e identificar las accesionesmás tolerantes para su empleo en los programas de mejoramiento genético. Para ello se calcularon los parámetros estadísticos:media, rango y coeficiente de variación de los caracterestermoestabilidad de la membrana celular (TMC y viabilidadcelular (VC, evaluados a nivel de tejido, así como de los caracteresy criterios de tolerancia: fructificación potencial (FP, fructificaciónen condiciones de estrés (FE, fructificación geométrica del estrés(FGE, tolerancia (TOL, índice de susceptibilidad al estrés (ISE,índice de tolerancia al estrés (ITE e índice de tolerancia relativo(ITR, evaluados a nivel de planta. Se evaluó, asimismo, la relaciónexistente entre estos, mediante estimaciones del índice de coincidencia de las mejores y peores accesiones, y la correlaciónexistente entre ellos. Se pudo comprobar que las evaluaciones anivel de tejido, especialmente la TMC, tuvo altos índices de coincidencia y correlación positiva con los criterios de toleranciaa nivel de planta, sobre todo con ITE o FGE, determinándose 18accesiones que coincidentemente se clasificaron como tolerantes al calor por todos los indicadores evaluados, las cuales seproponen como progenitores en los programas de mejoramientopara tolerancia al calor en el cultivo.

  3. EVALUACIÓN DE LA TOLERANCIA AL CALOR A NIVEL DE PLANTA EN EL GERMOPLASMA DE TOMATE (Solanum L. sección Lycopersicon subsección Lycopersicon CONSERVADO Ex Situ

    Directory of Open Access Journals (Sweden)

    Marilyn Florido

    2009-01-01

    Full Text Available Este trabajo se desarrolló con el objetivo de evaluar la tolerancia al calor en una muestra representativa del germoplasma de tomate (Solanum L. sección Lycopersicon subsección Lycopersicon conservado ex situ en las colecciones cubanas e identificar las accesiones más tolerantes para su empleo en los programas de mejoramiento genético. Para ello se evaluó el porcentaje de fructificación en los períodos óptimo y estresante (primavera-verano del cultivo, para calcular los criterios de estrés siguientes: índice de susceptibilidad al estrés (ISE, valor de tolerancia al estrés (TOL, índice de tolerancia al estrés (ITE, fructificación geométrica del estrés (FGE e índice de tolerancia relativo (IT. Se clasificaron las 122 accesiones por su tolerancia al calor a nivel de planta en base al porcentaje de fructificación en siembras de primavera-verano y la relación entre los índices de tolerancia evaluados se efectuó mediante análisis Biplot. Se pudo comprobar que en el germoplasma evaluado existieron accesiones con altos porcentajes de fructificación en el período de primavera-verano, lo cual indica que en el germoplasma que se conserva ex situ en Cuba existen accesiones tolerantes al calor, que pueden ser explotadas en los programas de mejoramiento genético para obtener variedades e híbridos con buen comportamiento en estas condiciones.

  4. Optimization of air conditioning systems utilizing low temperature thermal storage; Optimizacion de sistemas de acondicionamiento de aire utilizando sistemas de almacenamiento termico de baja temperatura

    Energy Technology Data Exchange (ETDEWEB)

    Contreras Ramirez, J.; Dorantes Rodriguez, R. [Departamento de Energia, Universidad Autonoma Metropolitana - Unidad Azcapotzalco, Mexico, D. F. (Mexico)

    1997-12-31

    sistemas esta relacionado con la variabilidad de la carga termica y las posibilidades de regulacion de la o las maquinas termicas, de tal manera de lograr, a lo largo del dia, un adecuado uso y optimizacion de la carga total instalada, con los mejores beneficios economicos posibles. Entre las estrategias que permiten optimizar la capacidad de la instalacion y la variacion de la carga termica esta el almacenamiento termico de baja temperatura, por ejemplo, el almacenamiento de hielo, el cual se produce y se almacena durante las horas en que normalmente las maquinas de refrigeracion estan paradas, y con el fin de usar esta energia almacenada durante el horario pico y durante las horas de operacion normal del equipo, pero disminuyendo en forma importante la demanda electrica de la instalacion al satisfacer la carga termica con una combinacion almacen termico-maquina de refrigeracion. En este trabajo se presentan algunos antecedentes y tipos de almacenes termicos utilizados comunmente, se discute una metodologia que permite dimensionar un almacen termico, tanto tecnica como economicamente, y se plantean algunos de los problemas en el control y operacion de estos sistemas termicos.

  5. Modelación y Simulación de la Transferencia de Calor en Muros de Bloque de Concreto Hueco Modeling and Simulation of Heat Transfer in Hollow Concrete Block Walls

    OpenAIRE

    Ana C Borbón; Rafael E Cabanillas; Jesús B Pérez

    2010-01-01

    Se presenta el estudio de transferencia de calor en un muro de bloques de concreto con cavidades, para conocer su resistencia térmica. Se plantea un modelo teórico unidimensional en estado estacionario, considerando conducción, radiación y convección. El problema se resuelve numéricamente utilizando el método iterativo de Gauss-Seidel. La simulación se efectúa en forma horaria para dos días en condiciones extremas de temperatura ambiente. Se obtiene un valor promedio de la resistencia térmica...

  6. Validación de dos métodos analíticos: calor de combustión y azufre, en materiales combustibles que pueden ser quemados en hornos de clinker

    Directory of Open Access Journals (Sweden)

    Karen Hooker

    2010-10-01

    Full Text Available Se validaron dos métodos para llevar a cabo la evaluación fisicoquímica de materiales de desecho de diferentes empresas interesadas en tratar sus residuos, para utilizarlos como combustible alternativo para un horno de cemento, que calcina estos materiales a una temperatura máxima de 2000°C. Con este fin se optimizaron las figuras de mérito de la determinación del calor de combustión y del porcentaje de azufre.

  7. Analytical model to describe the thermal behavior of a heat discharge system in roofs; Modelo analitico que describe el comportamiento termico de un sistema de descarga de calor en techos

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez-Gomez, V.H.; Contreras-Espinosa, J.J.; Gonzalez-Ortiz, G.; Morillon-Galvez, D.; Fernandez-Zayas, J.L. [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico)]. E-mail: vichugo@servidor.unam.mx; jjuancon2000@yahoo.com.mx; gilberto_gonzalez25@hotmail.com; damg@pumas.iingen.unam.mx; JFernandezZ@iingen.unam.mx

    2012-01-15

    The present study proposes an analytical model which describes the thermal behavior of a heat discharge system in roof, when the surfaces that constitute it are not translucent. Such a model derives from a thermal balance carried out to a heat discharge system in roofs. To validate it, an experimental prototype that allows simulating the thermal behavior of a heat discharge system in wall and roof was used, and the results were compared to those obtained with the proposed analytical model. It was found that the thermal behavior of the analytical model is similar to the thermal behavior of the experimental prototype; a worthless variation was detected among their respective outcome (The difference of temperatures can be caused by the heat transfer coefficient, of which no studies defining its behavior accurately have been found). Therefore, it can be considered that the proposed analytical model can be employed to simulate the thermal behavior of a heat discharge system in roofs when the surfaces that constitute it are opaque. [Spanish] En el presente estudio se propone un modelo analitico que describe el comportamiento termico de un sistema de descarga de calor en techo, cuando las superficies que lo componen no son translucidos. Dicho modelo surge a partir de un balance termico realizado a un sistema de descarga de calor en techos. Para validarlo, se realizaron dos corridas experimentales en un prototipo que permite simular el comportamiento termico de un sistema de descarga de calor en techo y se compararon los resultados medidos con los calculados por el modelo analitico propuesto. Se encontro que, el comportamiento termico del modelo analitico es similar al comportamiento termico del prototipo experimental, se detecto una variacion despreciable entre los valores arrojados por ambos modelos (la diferencia de temperaturas puede estar ocasionada por la obtencion del coeficiente convectivo de transferencia de calor, del cual no se han encontrado estudios que

  8. Instalación distric heating con energía solar y almacenamiento estacional de calor

    OpenAIRE

    González Mantecón, Miguel Alfonso

    2013-01-01

    Algunos de los objetivos de este proyecto son presentar el estado actual de los sistemas de calefacción por distrito (District Heating, DH), definir sus componentes y presentar sus distintas configuraciones. En este proyecto se lleva a cabo un estudio del comportamiento térmico que tendrá un sistema de calefacción por distrito ubicado en Madrid. Se ha desarrollado una simulación del funcionamiento partiendo de datos meteorológicos reales recogidos en el Instituto Eduardo Torroj...

  9. Acumulación de calor con materiales de cambio de fase en aplicaciones de energía solar

    OpenAIRE

    Domínguez Alonso, Manuel; García Rodríguez, Carmen

    2008-01-01

    6 págs.-- Ponencia presentada en el XIV Congreso Ibérico y IX Congreso Iberoamericano de Energía Solar "Construyendo el futuro sostenible" (Vigo, 17-21 junio 2008). Publicada en el Libro de Actas, eds, Manuel Vázquez y José M. Santos.

  10. Effects of Caloric Restriction on Cardiac Oxidative Stress and Mitochondrial Bioenergetics: Potential Role of Cardiac Sirtuins

    Directory of Open Access Journals (Sweden)

    Ken Shinmura

    2013-01-01

    Full Text Available The biology of aging has not been fully clarified, but the free radical theory of aging is one of the strongest aging theories proposed to date. The free radical theory has been expanded to the oxidative stress theory, in which mitochondria play a central role in the development of the aging process because of their critical roles in bioenergetics, oxidant production, and regulation of cell death. A decline in cardiac mitochondrial function associated with the accumulation of oxidative damage might be responsible, at least in part, for the decline in cardiac performance with age. In contrast, lifelong caloric restriction can attenuate functional decline with age, delay the onset of morbidity, and extend lifespan in various species. The effect of caloric restriction appears to be related to a reduction in cellular damage induced by reactive oxygen species. There is increasing evidence that sirtuins play an essential role in the reduction of mitochondrial oxidative stress during caloric restriction. We speculate that cardiac sirtuins attenuate the accumulation of oxidative damage associated with age by modifying specific mitochondrial proteins posttranscriptionally. Therefore, the distinct role of each sirtuin in the heart subjected to caloric restriction should be clarified to translate sirtuin biology into clinical practice.

  11. Cardiac Frequency and Caloric Cost of Aerobic Dancing in Young Women.

    Science.gov (United States)

    Nelson, Deborah J.; And Others

    1988-01-01

    A study of cardiac frequency during aerobic dancing indicated that it can sustain an elevated cardiac frequency in most cases. The caloric cost of aerobic dancing is approximately 50 percent greater than an equal duration of barre and center-floor exercise by elite ballet dancers. (JD)

  12. A critique of Sadi Carnot's work and a mathematical theory of the caloric

    CERN Document Server

    Dass, N D Hari

    2013-01-01

    In this work, Sadi Carnot;s fundamental work is critically examined, and contrasted with modern thermodynamics. A mathematical theory of his work is given on the basis of the observation that in caloric theory dQ is a perfect differential.

  13. Análisis comparativo del aprendizaje de los conceptos de calor y temperatura utilizando una simulación digital interactiva y un texto ilustrado

    Directory of Open Access Journals (Sweden)

    Cimenna Chao Rebolledo

    2014-06-01

    Full Text Available Esta investigación analizó las diferencias que subyacen al aprendizaje de los conceptos de calor y temperatura en relación a los conceptos de energía térmica y energía cinética, a través de dos modalidades instruccionales: mediante la lectura de un texto ilustrado y a través de una simulación digital interactiva. Se trabajó con alumnos de dos grados escolares : 48 alumnos de segundo de secundaria sin instrucción previa sobre dichos fenómenos y 48 alumnos de tercero de secundaria con conocimientos académicos previos sobre los temas revisados. Se observaron diferencias significativas en la resolución de problemas asociados a los conceptos estudiados siendo mejor el desempeño de los participantes que utilizaron la simulación digital interactiva durante el aprendizaje y significativamente mejor en los alumnos con instrucción previa sobre dichos conceptos. El desempeño de los grupos que utilizaron el texto ilustrado fue significativamente mejor que su contraparte en problemas orientados a la definición literal de los fenómenos estudiados.

  14. Caracterización de mezclas de poliamina alifática comercial con sacarosa, zeolita y composites metálicos mediante espectrometría FTIR

    Directory of Open Access Journals (Sweden)

    Mercedes Guerra

    2010-01-01

    Full Text Available Se caracteriza la mezcla de poliamina alifática comercial con sacarosa, zeolita y composites con aluminio, bronce y hierro, así como mezclas de éstos con resinas furano epoxídicas (FAM, tratadas con y sin calor, mediante espectroscopía FTIR. La caracterización se comienza por la asignación de los espectros IR de cada uno de los componentes de la mezcla y se muestran las posiciones de las bandas con las asignaciones de las frecuencias características más importantes de los componentes que cumplen con la estructura química planteada. Del análisis de los espectros IR se reporta la desaparición de la banda de vibración de streching de la amina primaria y se mantiene la banda de vibración de streching del grupo OH 3350 cm-1 con baja intensidad, lo que evidencia una reacción química con los grupos aminos y OH, pero se observa C-N. Se mantienen las bandas con frecuencia características del anillo furánico y la estructura cíclica de la sacarosa. El tratamiento con calor, aparentemente, no influye sobre la estructura molecular de la mezcla.

  15. Evaluación de Intercambiadores de Calor Compactos de Tubos Aletados Evaluation of Compact Finned-Tube Heat Exchangers

    Directory of Open Access Journals (Sweden)

    M.T. Martínez

    2004-01-01

    Full Text Available En este trabajo, se presenta el análisis térmico teórico de un intercambiador de calor compacto, con y sin condensación de agua en el lado del aire. El fenómeno de la condensación del vapor de agua en la corriente de aire entrante produce una película de agua en la superficie cubriéndola en forma parcial o completa. El análisis considera varias configuraciones geométricas con respecto a: la superficie de las aletas y a la forma de los tubos considerando la forma circular tradicional y también un caso para tubos planos. Los resultados obtenidos reflejan la eficiencia de la aleta en ambos casos: una aleta totalmente seca (sin condensación y a una totalmente húmeda es decir, totalmente cubierta por la película de condensado. Se concluye que la metodología propuesta es una buena alternativa de análisis y caracterización de un intercambiador, ya que los resultados obtenidos coinciden con los reportados en la literaturaThis study presents a theoretical thermal analysis of a compact heat exchanger, with and without water condensation on the air side. The phenomenon of condensation of water vapor in the entering air current produces a film of water on the surface, partially or completely covering the surface. The analysis considers various geometric configurations with respect to the surfaces of the fins and the form of the tubes, including the traditional round form as well as flattened tubes. The results obtained reflect the efficiency of the fins in both cases , including a completely dry fin (no condensation and a completely wet fin, that is completely covered with a film of condensate. It is concluded that the methodology proposed is a good alternative for the analysis and characterization of a heat exchanger since the results agree with those reported in the literature

  16. Simulación numérica en Ingeniería y Ciencias con MATLAB + COMSOL Multiphysics

    OpenAIRE

    Ivorra, Benjamin

    2015-01-01

    En este seminario se tratan las posibles interacciones entre el entorno de programación matricial MATLAB y el software COMSOL Multiphysics, que permite resolver de forma intuitiva sistemas de ecuaciones en derivadas parciales con diversas implementaciones del método de los elementos finitos. Este tipo de ecuaciones modelan los fenómenos correspondientes a los problemas de mecánica de fluidos, transferencia de calor, electromagnetismo, etc. La posibilidad del uso combinado es importante, en pa...

  17. Caloric test results in Paget ́s disease of bone

    Directory of Open Access Journals (Sweden)

    De la Fuente-Cañibano R

    2013-04-01

    Full Text Available Introduction: In Paget's disease, the most common neurological complication relates to the temporal bone involvement intrapetrous level. Vestibular symptoms are common in Paget's disease, but you can pass easily overlooked for its mild intensity. The literature is not clear regarding the result of caloric testing.Methods: The study comprised 50 patient s, 30 patients with PD without skull involvement, 13 patients with skull involvement and without temporal involvement and 7 patients with PD with skull and temporal involvement in scintigraphy. Results: 22% of patient s in the sample had history crises dizzying and yet 46% had deficits in vestibular caloric test result.Conclusions: We found no statistically significant differences between the groups in the analysis of EP vestibular deficit.

  18. (Magneto)caloric refrigeration: is there light at the end of the tunnel?

    Science.gov (United States)

    Pecharsky, Vitalij K; Cui, Jun; Johnson, Duane D

    2016-08-13

    Caloric cooling and heat pumping rely on reversible thermal effects triggered in solids by magnetic, electric or stress fields. In the recent past, there have been several successful demonstrations of using first-order phase transition materials in laboratory cooling devices based on both the giant magnetocaloric and elastocaloric effects. All such materials exhibit non-equilibrium behaviours when driven through phase transformations by corresponding fields. Common wisdom is that non-equilibrium states should be avoided; yet, as we show using a model material exhibiting a giant magnetocaloric effect, non-equilibrium phase-separated states offer a unique opportunity to achieve uncommonly large caloric effects by very small perturbations of the driving field(s).This article is part of the themed issue 'Taking the temperature of phase transitions in cool materials'. PMID:27402923

  19. Control de l'escintil·lador SPD del calorímetre d'LHCb

    OpenAIRE

    Roselló Canal, Maria del Mar

    2009-01-01

    En aquesta tesi es descriu l'electrònica i la gestió de la placa de control de l'SPD. SPD són les sigles corresponents a Scintillator Pad Detector, part del calorímetre d'LHCb de l'accelerador LHC.L'LHC és un accelerador orientat a estudiar els constituents de la matèria on LHCb n'és un dels detectors. El calorímetre és aquella part del detector destinada a mesurar l'energia de les partícules que el travessen. En el nostre cas l'SPD discrimina entre partícules carregades i no carregades contr...

  20. Análisis de la máxima intensidad de la isla de calor urbana nocturna de la ciudad de Rancagua (Chile y sus factores explicativos.

    Directory of Open Access Journals (Sweden)

    Pablo Sarricolea

    2008-12-01

    Full Text Available Las ciudades constituyen el hábitat por excelencia de los seres humanos, y pese a su diversidad presentan características ambientales (clima urbano comunes en muchas partes del mundo, como por ejemplo la presencia de la Isla de Calor Urbana (ICU, que corresponde a un aumento de origen antrópico de las temperaturas de la ciudad en comparación con su entorno inmediato de carácter natural y rural, siendo más intensa dicha diferencia en las noches. Por ello, el propósito de esta investigación es analizar la Máxima Intensidad de la Isla de Calor Urbana (MIICU de Rancagua a partir de mediciones de las temperaturas con transectos móviles y estaciones meteorológicas fijas. Se ha determinado que la máxima intensidad de la isla de calor urbana de Rancagua bordea los 6°C en verano y primavera, y 3°C para invierno y otoño. Los factores que explican las distribuciones de las temperaturas urbanas de Rancagua corresponden a las distancias a fuentes húmedas (río Cachapoal y las densidades poblacionales; y en menor medida las características topográficas del emplazamiento de la ciudad y las áreas verdes urbanas medidas a partir del índice normalizado de diferencias vegetales (NDVI. La principal conclusión de esta investigación indica que la ausencia de parques urbanos en Rancagua explica la distribución de las temperaturas y la elevada intensidad de la isla de calor, y también la no significativa relación entre temperaturas y NDVI. De no revertirse esta situación, la sostenibilidad ambiental futura de la ciudad de Rancagua se verá muy amenazada por el crecimiento urbano.Cities are the environment for excellence in human beings, and despite their diversity, environmental features (urban climate are common in many parts of the world, such as the presence of the Urban Heat Island (UHI. This corresponds to a temperature increase due to human activities in the city compared with its immediate natural and rural surroundings, the difference

  1. Impact of Six-Month Caloric Restriction on Autonomic Nervous System Activity in Healthy, Overweight, Individuals

    OpenAIRE

    de Jonge, Lillian; Moreira, Emilia AM; Martin, Corby K.; Ravussin, Eric

    2009-01-01

    Caloric restriction (CR) increases maximum lifespan but the mechanisms are unclear. Dominance of the sympathetic nervous System (SNS) over the Parasympathetic Nervous System (PNS) has been shown to be a strong risk factor for cardiovascular disease. Obesity and aging are associated with increased SNS activity and weight loss and/or exercise seem to have positive effects on this balance. We therefore evaluated the effect of different approaches of CR on autonomic function in 48 overweight indi...

  2. Attenuation of age-related changes in mouse neuromuscular synapses by caloric restriction and exercise

    OpenAIRE

    Valdez, G; Tapia, J; Kang, H; Clemenson, G.D.; Gage, F.H.; Lichtman, Jeff; Sanes, Joshua R.

    2010-01-01

    The cellular basis of age-related behavioral decline remains obscure but alterations in synapses are likely candidates. Accordingly, the beneficial effects on neural function of caloric restriction and exercise, which are among the most effective anti-aging treatments known, might also be mediated by synapses. As a starting point in testing these ideas, we studied the skeletal neuromuscular junction (NMJ), a large, accessible peripheral synapse. Comparison of NMJs in young adult and aged mice...

  3. Vestibular Function Tests for Vestibular Migraine: Clinical Implication of Video Head Impulse and Caloric Tests

    Science.gov (United States)

    Kang, Woo Seok; Lee, Sang Hun; Yang, Chan Joo; Ahn, Joong Ho; Chung, Jong Woo; Park, Hong Ju

    2016-01-01

    Vestibular migraine (VM) is one of the most common causes of episodic vertigo. We reviewed the results of multiple vestibular function tests in a cohort of VM patients who were diagnosed with VM according to the diagnostic criteria of the Barany Society and the International Headache Society and assessed the efficacy of each for predicting the prognosis in VM patients. A retrospective chart analysis was performed on 81 VM patients at a tertiary care center from June 2014 to July 2015. Patients were assessed by the video head impulse test (vHIT), caloric test, vestibular-evoked myogenic potentials (VEMPs), and sensory organization test (SOT) at the initial visit and then evaluated for symptomatic improvement after 6 months. Complete response (CR) was defined as no need for continued medication, partial response (PR) as improved symptoms but need for continued medication, and no response (NR) as no symptomatic improvement and requiring increased dosage or change in medications. At the initial evaluation, 9 of 81 patients (11%) exhibited abnormal vHIT results, 14 of 73 (19%) exhibited abnormal caloric test results, 25 of 65 (38%) exhibited abnormal SOT results, 8 of 75 (11%) exhibited abnormal cervical VEMP results, and 20 of 75 (27%) exhibited abnormal ocular VEMP results. Six months later, 63 of 81 patients (78%) no longer required medication (CR), while 18 (22%) still required medication, including 7 PR and 11 NR patients. Abnormal vHIT gain and abnormal caloric results were significantly related to the necessity for continued medication at 6-month follow-up (OR = 5.67 and 4.36, respectively). Abnormal vHIT and caloric test results revealed semicircular canal dysfunction in VM patients and predicted prolonged preventive medication requirement. These results suggest that peripheral vestibular abnormalities are closely related to the development of vertigo in VM patients.

  4. General and persistent effects of high-intensity sweeteners on body weight gain and caloric compensation in rats

    OpenAIRE

    Swithers, Susan E.; Baker, Chelsea R.; Davidson, T.L.

    2009-01-01

    In four experiments, we assessed the generality of previous findings (Swithers & Davidson, 2008) that increased caloric intake, body weight gain, and reduced caloric compensation are exhibited by rats that consume a diet containing a nonnutritive, high intensity sweetener. In this earlier work, rats consumed a diet in which saccharin was mixed in low-fat yogurt, and animals were provided with a fixed amount of the yogurt. The present experiments showed that the effects of saccharin on energy ...

  5. Feed restriction and a diet's caloric value: The influence on the aerobic and anaerobic capacity of rats

    OpenAIRE

    Moura Leandro; Kalva-Filho Carlos; Loures João; de Sousa Silva Maria; Zorzetto Lucas; Junior Marcelo; de Araújo Michel; Dalia Rodrigo; de Mello Maria

    2012-01-01

    Abstract Background The influence of feed restriction and different diet's caloric value on the aerobic and anaerobic capacity is unclear in the literature. Thus, the objectives of this study were to determine the possible influences of two diets with different caloric values and the influence of feed restriction on the aerobic (anaerobic threshold: AT) and anaerobic (time to exhaustion: Tlim) variables measured by a lactate minimum test (LM) in rats. Methods We used 40 adult Wistar rats. The...

  6. Method to allow the estimation of heat transfer coefficients in solar stills; Metodo para determinar coeficientes locales de transferencia de calor en destiladores solares

    Energy Technology Data Exchange (ETDEWEB)

    Rubio Cerda, Eduardo; Porta Gandara, Miguel A [CIBNOR, Mexico D.F (Mexico); Fernandez Zayas, Jose Luis [UNAM Mexico, D.F. (Mexico)

    2000-07-01

    This work reports an experimental method that allows to estimate the heat transfer coefficients in the neighborhood of walls or flat plates subject to convective transport phenomena. This method can be applied to a great variety of thermal systems since it is based on the knowledge of the border condition for the temperature at the surface of the plate, and the temperature profile that characterize the dimensionless coefficient of heat transfer in the fluid, according to its definition given by the Nusselt number. The approach of this work are the foundations of the method and the system that has been developed to apply it, that incorporates automatic acquisition equipment for continuos monitoring of the information and elements to control the parameters of interest. In addition, the experimental cavities on which the method will be evaluated are discussed, considering two different scales, as well as experiments in cavities filled with air, and with a mixture of air and steam water, as is the case for solar distillation. [Spanish] En este trabajo se presenta un metodo que permite determinar de manera experimental coeficientes de transferencia de calor por conveccion. Este metodo puede ser aplicado a una gran variedad de sistemas termicos ya que se fundamenta en el conocimiento de la condicion de frontera para la temperatura en la superficie de la placa, y del perfil de temperaturas que caracteriza el coeficiente adimensional de transferencia de calor en el fluido, de acuerdo a la definicion de este, dada por el numero de Nusselt. El trabajo que aqui se reporta esta enfocado a la fundamentacion del metodo y al equipamiento que se ha desarrollado para instrumentarlo, que incorpora equipos automaticos de adquisicion continua de informacion y elementos de control para los parametros de interes. Se presentan ademas, las cavidades experimentales sobre las que sera evaluado el metodo, que considera dos escalas diferentes, asi como experimentos en cavidades llenas de aire

  7. Fluid-structural dynamics of ground-based and microgravity caloric tests

    Science.gov (United States)

    Kassemi, M.; Oas, J. G.; Deserranno, Dimitri

    2005-01-01

    Microgravity caloric tests aboard the 1983 SpaceLab1 mission produced nystagmus results with an intensity comparable to those elicited during post- and pre- flight tests, thus contradicting the basic premise of Barany's convection hypothesis for caloric stimulation. In this work, we present a dynamic fluid structural analysis of the caloric stimulation of the lateral semicircular canal based on two simultaneous driving forces for the endolymphatic flow: natural convection driven by the temperature-dependent density variation in the bulk fluid and expansive convection caused by direct volumetric displacement of the endolymph during the thermal irrigation. Direct numerical simulations indicate that on earth, the natural convection mechanism is dominant. But in the microgravity environment of orbiting spacecraft, where buoyancy effects are mitigated, expansive convection becomes the sole mechanism for producing cupular displacement. A series of transient 1 g and microgravity case studies are presented to delineate the differences between the dynamics of the 1 g and microgravity endolymphatic flows. The impact of these different flow dynamics on the endolymph-cupula fluid-structural interactions is also analyzed based on the time evolutions of cupular displacement and velocity and the transcupular pressure differences.

  8. Importance of silvopastoral systems on caloric stress reduction in tropical livestock productions

    Directory of Open Access Journals (Sweden)

    Alexander Navas Panadero

    2010-06-01

    Full Text Available Livestock systems in Colombia have been developed taking concepts and technologies from the green revolution, where gramineous monocrop is privileged over arboreal cover in grazing lands. This model has not taken into account the climatic conditions of the different tropical ecosystems, in which variables as temperature, relative humidity and evaporation can limit the animal´s productive and reproductive efficiency, besides being a risk factor for illness occurrence in the herd. Bos Taurus and Bos Indicus breeds show termoneutral ranges where its genetic potential can be express. However, out of this comfort area animals can enter in caloric stress which in consequence reduces its performance and sometimes can end up causing death. Silvopastoral systems comprise several functions; it contributes to lessen caloric stress since temperature under the tree canopy can reach between 2 and 9°C lower in comparison to open pastures. Differences in temperature reduction have been found among silvopastoral systems and species, being the tree group arrangements and the species with high density canopy, those with superior effect. Interactions among components should be analyzed in order to design systems that incorporate enough arboreal cover to achieve caloric stress reductions, but without affecting forage production in pastures. Silvopastoral systems contribute to improve animal welfare.

  9. Effects of caloric deprivation and satiety on sensitivity of the gustatory system

    Directory of Open Access Journals (Sweden)

    Zverev Yuriy P

    2004-02-01

    Full Text Available Abstract Background Sensitivity of the gustatory system could be modulated by a number of short-term and long-term factors such as body mass, gender, age, local and systemic diseases and pathological processes, excessive alcohol drinking, drug dependence, smoking, composition of oral fluid, state of oral hygiene, consumption of some foods among many others. A few studies have demonstrated the effects of hunger and caloric satiety on sensitivity of the gustatory system in obese humans and animals. The aim of the present study was to assess the effects of short-term caloric deprivation and satiety on recognition taste thresholds of healthy, non-smoking, non-drinking, non-obese young male subjects. The two-alternative forced-choice technique was used to measure taste threshold. Results Recognition thresholds for sucrose and salt were significantly lower during fasting state than after a meal (t = 2.23, P Conclusions Short-term caloric deprivation in our study model was associated with increased taste sensitivity to sweet and salty substances compared to satiated state while taste sensitivity to bitter substances was not affected by the conditions of measurements. Selective modulation of sensitivity of the gustatory system might reflect the different biological importance of salty, sweet and bitter qualities of taste.

  10. Economic management of vertigo/dizziness disease in a county hospital: video-head-impulse test vs. caloric irrigation.

    Science.gov (United States)

    Rambold, Holger A

    2015-10-01

    The video-head-impulse test (vHIT) is an important test for examining unilateral vestibular hypofunction. Alternatively, one can test for vestibular hypofunction with the caloric irrigation test. Various studies have shown that both tests may not always identify vestibular hypofunction; instead, the results of the tests might be contradictory. This retrospective study reproduces those finding in a much larger group of patients at a county hospital. 1063 patients were examined with the vHIT and bithermal caloric irrigation on the same day and analyzed with respect to side differences. Of those patients 13.3% had pathological vHIT and a caloric irrigation test, 4.6% a pathological vHIT only and 24.1% a pathologic caloric test only. As both tests might be necessary, we calculated the optimal sequence of the two examinations based on savings in time for the different disease groups. Especially in vestibular failure using the vHIT first and only applying the caloric irrigation in case of an unremarkable vHIT saves time and optimizes the diagnostic work up. In contrast, in Menière's disease and vestibular migraine testing caloric irrigation first might be more efficient.

  11. Saccharin and aspartame, compared with sucrose, induce greater weight gain in adult Wistar rats, at similar total caloric intake levels.

    Science.gov (United States)

    Feijó, Fernanda de Matos; Ballard, Cíntia Reis; Foletto, Kelly Carraro; Batista, Bruna Aparecida Melo; Neves, Alice Magagnin; Ribeiro, Maria Flávia Marques; Bertoluci, Marcello Casaccia

    2013-01-01

    It has been suggested that the use of nonnutritive sweeteners (NNSs) can lead to weight gain, but evidence regarding their real effect in body weight and satiety is still inconclusive. Using a rat model, the present study compares the effect of saccharin and aspartame to sucrose in body weight gain and in caloric intake. Twenty-nine male Wistar rats received plain yogurt sweetened with 20% sucrose, 0.3% sodium saccharin or 0.4% aspartame, in addition to chow and water ad libitum, while physical activity was restrained. Measurements of cumulative body weight gain, total caloric intake, caloric intake of chow and caloric intake of sweetened yogurt were performed weekly for 12 weeks. Results showed that addition of either saccharin or aspartame to yogurt resulted in increased weight gain compared to addition of sucrose, however total caloric intake was similar among groups. In conclusion, greater weight gain was promoted by the use of saccharin or aspartame, compared with sucrose, and this weight gain was unrelated to caloric intake. We speculate that a decrease in energy expenditure or increase in fluid retention might be involved.

  12. CARACTERIZACIÓN MOLECULAR Y GERMINACIÓN DE SEMILLAS DE MAÍCES CRIOLLOS AZULES CON ENVEJECIMIENTO ACELERADO

    Directory of Open Access Journals (Sweden)

    Dagoberto Dur\\u00E1n-Hern\\u00E1ndez

    2011-01-01

    Full Text Available El objetivo del presente estudio fue determinar el efecto del envejecimie nto acelerado en semillas de varie dades criollas de maíz azul. En los laboratorios de la Universidad Nacional Autónoma de México y del Instituto Politécnico Nacional, semillas de cuatro varie dades criollas de maíz azul (Cuijingo, Cocotitlán, Puebla y Oaxaca, se sometie ron a dos tip os de envejecimie nto acelerado: calor húmedo (41°C, 72 horas y 100% h. r. y calor seco (60°C, 48 horas. Se evaluaron: protrusión radicular de 0 a 72 horas de imbibición y, a los sie te días de incubación a 25°C, plántulas normales, anormales y semillas muertas. Se obtuvo la caracterización molecular de los tratamie ntos mediante la RA PD y se construyeron los dendogramas respectivos. En plántulas normales provenie ntes de semillas sin envejecimie nto acelerado, las varie dades Oaxaca y Puebla fueron significativamente superiores. El peso seco en las plántulas disminuyó con el deterioro, sie ndo exigua con calor seco. La presencia de plántulas anormales se incrementó con ambos tip os de deterioro en el orden: Oaxaca, Puebla, Cocotitlán y Cuijingo. La diferenciación de los perfiles de bandeo entre semillas testigo y deterioradas ocurrió con la secuencia: Oaxaca (31,6%, Cocotitlán (25,8%, Puebla (19,6% y Cuijingo (18,6%. Estos valores de similitud, a los cuales se ramificaron los perfiles genómicos, se asociaron de manera inversa con el nivel de vigor de las semillas, y directamente con la presencia de anormalidades en las plántulas obtenidas.

  13. Cuidados con el anciano con tos productiva.

    OpenAIRE

    Costa de Moura, María Lucia

    2005-01-01

    A partir de las informaciones y con la motivación para hacer un estudio dirigido a los cuidados con el anciano, sigue la necesidad del desarrollo de acciones pertinentes para la práctica de cuidar, o sea, la asistencia de enfermería prestada directamente al anciano, principalmente a aquellos que llegan a la unidad de salud quejándose de tos. El objeto de este estudio es la asistencia de enfermería basándome en las cuestiones que rodean la percepción del enfermero y cómo el...

  14. Modelación de la transferencia de calor y masa en el absorbedor de una máquina de refrigeración por absorción. // Heat and mass transference modeling in the absorvetor of an absorption cooling device.

    Directory of Open Access Journals (Sweden)

    C. Cisneros Ramírez

    2003-01-01

    Full Text Available En este artículo se dan las expresiones que caracterizan el comportamiento de la temperatura y del producto coeficienteglobal de traspaso de calor (U por el área de traspaso de calor (A , de un absorbedor de una máquina de refrigeración porabsorción que trabaja con la solución amoniaco – agua.Palabras claves: Modelación, absorbedores, refrigeración por absorción.______________________________________________________________________________Abstract.In this article the expressions that characterize the temperature performance and the global heat exchange (U by the heatexchange area (A of the absorvetor of an absorption refrigerating equipment with aqua–ammonia solution are given.Key words: Model, absorber, absorption refrigeration.

  15. Estudio termoeconómico de diferentes configuraciones de ciclo combinado integrado con una planta solar

    Directory of Open Access Journals (Sweden)

    María Dolores Durán García

    2014-01-01

    Full Text Available Se presenta el análisis termoeconómico de una planta de ciclo combinado integrada con una planta solar de canal parabólico, considerada como una sección de la caldera de recuperación de calor, con el objetivo de conseguir un diseño óptimo al determinar los parámetros de diseño optimizados para ambos sistemas. Se aplica una metodología empleada en trabajos previos para la optimización de ciclos combinados, pero ahora con una planta solar. Como resultado, a partir de un análisis de sensibilidad, se obtiene el desempeño de varias configuraciones bajo diferentes condiciones de radiación solar.

  16. Intake of High-intensity Sweeteners alters the Ability of Sweet Taste to Signal Caloric Consequences: Implications for the Learned Control of Energy and Body Weight Regulation

    OpenAIRE

    Davidson, Terry L.; Martin, Ashley A.; Clark, Kiely; Swithers, Susan E.

    2011-01-01

    Recent results from both human epidemiological and experimental studies with animals suggest that intake of non-caloric sweeteners may promote, rather than protect against, weight gain and other disturbances of energy regulation. However, without a viable mechanism to explain how consumption of non-caloric sweeteners can increase energy intake and body weight, the persuasiveness of such results has been limited. Using a rat model, the present research showed that intake of non-caloric sweeten...

  17. El estrés calórico y su amortiguamiento a través de las proteínas del estrés (Hsp - Caloric stress and your deadening to the heat shock protein, Hsp

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    Sánchez-Rodríguez, Sergio Hugo

    2007-12-01

    Full Text Available ResumenLa hipertermia es una amenaza potencial para la vida y es sorprendente como los organismos homeotermos poseen mecanismos fisiológicos de adaptación que reducen los efectos de la hipertermia, mediante la disminución de la producción interna de calor, por incremento en la resistencia del flujo de calor del medio ambiente hacia el organismo y el del flujo de calor del organismo al medio ambiente. El conocimiento de como los organismos responden al estrés calórico a nivel celular es incipiente. Un importante esfuerzo para dilucidar la respuesta celular al estrés calórico se ha dirigido a una familia de proteínas conocidas como proteínas de choque calórico o proteínas chaperonas. Las proteínas de choque calórico, son constituyentes normales de las células y su síntesis se incrementa con la exposición a diversas formas de estrés.SummaryHyperthermia is a potential threat for living and its amazing how homeothermic organism must have or acquire adaptative physiological machanismo that prevent harmfull effects of hyperthermia by reducing inner heat production, by increasing heat flow resistance from theenvironmental to the organism and by increasing the heat flow from the organiosm to the environmental.The knowledge of how the organism respond to heat stress at the cellular leavel is minimal.An important effort to dillucidate the cellular response to heat stress has led to the knowledge of protein family called heat-shock proteins or chaperone proteins. Heat-shock proteins are normal constituents of the living cell and their synthesis increase in response to exposure to several types of stressful agents.

  18. Longitudinal Relationships between Caloric Expenditure and Gray Matter in the Cardiovascular Health Study

    Science.gov (United States)

    Raji, Cyrus A.; Merrill, David A.; Eyre, Harris; Mallam, Sravya; Torosyan, Nare; Erickson, Kirk I.; Lopez, Oscar L.; Becker, James T.; Carmichael, Owen T.; Gach, H. Michael; Thompson, Paul M.; Longstreth, W.T.; Kuller, Lewis H.

    2016-01-01

    Background: Physical activity (PA) can be neuroprotective and reduce the risk for Alzheimer’s disease (AD). In assessing physical activity, caloric expenditure is a proxy marker reflecting the sum total of multiple physical activity types conducted by an individual. Objective:To assess caloric expenditure, as a proxy marker of PA, as a predictive measure of gray matter (GM) volumes in the normal and cognitively impaired elderly persons. Methods: All subjects in this study were recruited from the Institutional Review Board approved Cardiovascular Health Study (CHS), a multisite population-based longitudinal study in persons aged 65 and older. We analyzed a sub-sample of CHS participants 876 subjects (mean age 78.3, 57.5% F, 42.5% M) who had i) energy output assessed as kilocalories (kcal) per week using the standardized Minnesota Leisure-Time Activities questionnaire, ii) cognitive assessments for clinical classification of normal cognition, mild cognitive impairment (MCI), and AD, and iii) volumetric MR imaging of the brain. Voxel-based morphometry modeled the relationship between kcal/week and GM volumes while accounting for standard covariates including head size, age, sex, white matter hyperintensity lesions, MCI or AD status, and site. Multiple comparisons were controlled using a False Discovery Rate of 5 percent. Results: Higher energy output, from a variety of physical activity types, was associated with larger GM volumes in frontal, temporal, and parietal lobes, as well as hippocampus, thalamus, and basal ganglia. High levels of caloric expenditure moderated neurodegeneration-associated volume loss in the precuneus, posterior cingulate, and cerebellar vermis. Conclusion:Increasing energy output from a variety of physical activities is related to larger gray matter volumes in the elderly, regardless of cognitive status. PMID:26967227

  19. Effects of emodin on treating murine nonalcoholic fatty liver induced by high caloric laboratory chaw

    Institute of Scientific and Technical Information of China (English)

    Hui Dong; Fu-Er Lu; Zhi-Qiang Gao; Li-Jun Xu; Kai-Fu Wang; Xin Zou

    2005-01-01

    AIM: To investigate the effects of emodin on the treatment of non-alcoholic fatty liver in rats induced by high caloric laboratory chaw.METHODS: Non-alcoholic fatty liver model was successfully established by feeding with high caloric laboratory chaw for 12 wk. Then the model rats were randomly divided into 3 groups, namely model control group, emodin group and dietary treatment group. The rats in emodin group in othergroups were given distilled water of the same volume. The rats in model control group were fed with high caloric laboratory chaw while animals in other groups were fed with normal diet. Four weeks later, liver index (liver/body weight ratio), serum activities of liver-associated enzymes, blood lipid, fasting blood glucose, fasting plasma insulin, HOMA insulin resistance index (HOMA-IR), hepatic triglyceride content and histology features of all groups were assayed. The expression of hepatic peroxisomal proliferator activated receptor (PPAR) gamma was determined by RT-PCR.RESULTS: The body weight, liver index, serum activities of alanine aminotransferase (ALT), blood lipid, hepatic triglyceride content of model control group were significantly elevated, with moderate to severe hepatocyte steatosis.The expression of hepatic PPAR gamma mRNA was obviously reduced in model control group. Compared with model control group, the body weight, liver index, serum activities of ALT, blood lipids and hepatic triglyceride of emodin group significantly decreased and hepatic histology display was also greatly improved. Meanwhile, the expression of hepatic PPAR gamma mRNA was elevated.However, high serum activities of ALT and hyperlipidemia were persisted in dietary treatment group although liver index was decreased and liver histology was somewhat improved.CONCLUSION: It is suggested that emodin might be effective in the treatment of non-alcoholic fatty liver in rats. Its therapeutic mechanism could be associated with increasing the expression of hepatic PPAR gamma mRNA.

  20. Olas de calor e influencia urbana en Madrid y su área metropolitana

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    Fernández García, F.

    2008-12-01

    Full Text Available The frequency and duration of the warmest temperature episodes, a common phenomenon under the continental Mediterranean conditions of the Spanish Southern Meseta, has increased in the Madrid area since the 80´s, although their magnitude remains unchanged. The effect of the urban environment on those extreme events has exacerbated the heat load due to the persistence of the high temperatures along the night time hours. Nevertheless, the diversity of the urban morphology introduces a spatial variability on the strength of this nocturnal heat load, aggravating it in the densely urbanized areas and mitigating it in the vicinities of the green areas.

    La frecuencia y duración de los episodios cálidos extremos, un fenómeno habitual en el clima mediterráneo continental de la Meseta Meridional, ha aumentado en el área de Madrid desde los años noventa, aunque su magnitud permanece constante. En el interior de la aglomeración urbana, el efecto general de la ciudad sobre estos eventos climáticos extremos ha supuesto una exacerbación del calor, no tanto por un aumento de la temperatura máxima, como por una persistencia del calor en las horas nocturnas. No obstante, la diversidad de la morfología urbana introduce variaciones espaciales en la intensidad de este calor nocturno, agravando sus efectos en las áreas densamente urbanizadas y mitigándolos en las proximidades de las áreas verdes.

  1. Rapid relief of thalamic pain syndrome induced by vestibular caloric stimulation.

    Science.gov (United States)

    Ramachandran, Vilayanur S; McGeoch, Paul D; Williams, Lisa; Arcilla, Gerard

    2007-06-01

    Central post-stroke pain syndrome develops in a minority of patients following a stroke. The most usual causative lesion involves the lateral thalamus. The classic presentation is of severe, unrelenting pain that involves the entire contralateral half of the body. It is largely refractory to current treatments. We found that in two patients with this condition their pain was substantially improved by vestibular caloric stimulation, whereas placebo procedures had no effect. We proposed that this is because vestibular stimulation activates the posterior insula, which in turn inhibits the generation of pain in the anterior cingulate.

  2. Evaluation of a direct contact heat exchanger; Evaluacion de un intercambiador de calor de contacto directo

    Energy Technology Data Exchange (ETDEWEB)

    Siqueiros, J.; Bonilla, O. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    In this paper the application areas of the direct contact heat exchangers is discussed, as well as its main characteristics. A description is made of the experimental equipment designed and built at pilot scale including the instrumentation employed. The methodology employed as well as the analysis and the discussion of the results are also presented. [Espanol] Se mencionan las areas de aplicacion de los intercambiadores de calor de contacto directo, asi como sus caracteristicas principales. Se describe el equipo experimental a nivel piloto disenado y construido incluyendo la instrumentacion utilizada. Se presenta la metodologia empleada asi como el analisis y discusion de los resultados.

  3. Identificación de incrustaciones en ciclones recuperadores de calor de hornos DOPOL

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    Triviño Vázquez, Fernando

    1979-12-01

    Full Text Available Not avaible

    En un ciclón recuperador de calor, situado a la entrada del horno de clinquerización tipo DOPOL, se producían unas incrustaciones sedimentarias que terminaban produciendo la obstrucción del ciclón. Simultáneamente aparecían dificultades de marcha durante el crecimiento, por sedimentación- fusión, de dichas incrustaciones. Finalmente era necesaria la parada del horno para la limpieza del ciclón.

  4. Impact of time since last caloric intake on blood glucose levels

    OpenAIRE

    Moebus, Susanne; Göres, Laura; Lösch, Christian; Jöckel, Karl-Heinz

    2011-01-01

    Blood glucose (BG) is usually measured after a caloric restriction of at least 8 h; however evidence-based recommendations for the duration of a fasting status are missing. Here we analyze the effect of fasting duration on levels of BG to determine the minimal fasting duration to achieve comparable BG levels to conventional fasting measurements. We used data of a cross-sectional study on primary care patients, performed in October 2005. We included 28,024 individuals (age-range 18–99 years; 6...

  5. Modelación y Simulación de la Transferencia de Calor en Muros de Bloque de Concreto Hueco Modeling and Simulation of Heat Transfer in Hollow Concrete Block Walls

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    Ana C Borbón

    2010-01-01

    Full Text Available Se presenta el estudio de transferencia de calor en un muro de bloques de concreto con cavidades, para conocer su resistencia térmica. Se plantea un modelo teórico unidimensional en estado estacionario, considerando conducción, radiación y convección. El problema se resuelve numéricamente utilizando el método iterativo de Gauss-Seidel. La simulación se efectúa en forma horaria para dos días en condiciones extremas de temperatura ambiente. Se obtiene un valor promedio de la resistencia térmica de 0.18 °Cm²/W, con variaciones de 2.3% a 23%. Las aportaciones al flujo total de calor por cada mecanismo son de 25%, 19% y 56%, para conducción, convección y radiación respectivamente. El muro presenta valores de resistencia térmica que tienden a disminuir con el aumento de los diferenciales de temperatura, aspecto que desfavorece su uso para climas cálidos, siendo la radiación el mecanismo que más favorece la transferencia de calor.This paper presents a heat transfers study in a hollow concrete blocks wall to know its thermal resistance. A one dimensional steady-state model was developed, which includes conduction, radiation and convection. The model was solved numerically using Gauss-Seidel iterative method. The simulation was run hourly for two days in climatic extreme conditions. The thermal resistance average value obtained was 0.18 °Cm²/W with variations of 2.3% to 23%. The average contribution to the total heat flow for every transfer mechanism is: 25%, 19% and 56% by conduction, convection and radiation respectively. The wall presents thermal resistance values which tend to decrease with the increase of temperature differential. This aspect presents disadvantages for thermal behavior in warm climate and the radiation into the block cavity is the most important heat transfer process across the wall.

  6. Caloric stimulation

    Science.gov (United States)

    ... be done to diagnose or rule out: Acoustic neuroma Benign positional vertigo Labyrinthitis Meniere disease Risks Too ... Elsevier Saunders; 2012:chap 37. Read More Acoustic neuroma Alertness - decreased Anemia Benign ear cyst or tumor ...

  7. Investigando con personas con dificultades de aprendizaje

    Directory of Open Access Journals (Sweden)

    Borja González Luna

    2013-12-01

    Full Text Available El artículo muestra los orígenes de lo que Walmsley (2008 denomina «investigación inclusiva». Para comprender qué se entiende por investigación inclusiva tenemos que remontarnos a los debates epistemológicos sobre las metodologías cuantitativas y cualitativas, acontecidos en la década de los 90, en torno a la revista Disability & Society. A partir de una síntesis de dichos debates, focalizados en el ámbito de la «discapacidad intelectual y del desarrollo», se exponen dos estrategias de colaboración con dicha población: a una aproximación etnográfica (de trabajo grupal, y b una aproximación biográfica (de trabajo individual. A continuación se esboza un posible diseño de trabajo de campo que intenta superar el paradigma cualitativo «clásico» con el objetivo de incluir a dicho colectivo más allá del rol de «sujetos de la investigación». Para finalizar se recoge el debate sobre la accesibilidad de los resultados de la investigación a los participantes en dichas investigaciones, y con ello la necesaria innovación en el ámbito de las «devoluciones» de los resultados, cuando se trata de incluir a personas que presentan limitaciones para la comprensión del lenguaje abstracto oral y/o escrito.

  8. Transferencia de calor en la colada continua de aceros. I parte. El molde

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    Cicutti, C.

    1997-10-01

    Full Text Available The continuous casting mold plays the important role of receiving the liquid steel and allowing an uniform and defect free solidified skin to be developed. In this work, the different heat transfer mechanisms which are present from the liquid steel to the mold cooling water are reviewed. The effect of operating variables on heat extraction and the relationship between global and distributed heat flux are also analyzed.

    El molde de colada continua cumple la importante función de recibir el acero líquido y permitir que se desarrolle una capa solidificada uniforme y libre de defectos. En este trabajo se revisan los distintos mecanismos implicados en el proceso de transferencia de calor, desde el acero líquido hasta el agua de refrigeración del molde. Se analiza también el efecto de las distintas variables de funcionamiento en la extracción calórica producida y la relación entre el flujo global de calor y su distribución a lo largo del molde.

  9. Caloric restriction and the precision-control of autophagy: A strategy for delaying neurodegenerative disease progression.

    Science.gov (United States)

    Ntsapi, C; Loos, B

    2016-10-01

    Caloric restriction (CR) is known to extend lifespan in most organisms, indicating that nutrient and energy regulatory mechanisms impact aging. The greatest risk factor for neurodegeneration is age; thus, the antiaging effects of CR might attenuate progressive cell death and avert the aggregation of abnormal proteins associated with neurodegenerative diseases. CR is a potent inducer of autophagy, a tightly regulated intracellular process that facilitates recycling of abnormal protein aggregates and damaged organelles into bioenergetic and biosynthetic materials to maintain homeostasis. Thus, dysregulated autophagy can lead to cellular dysfunction, abnormal protein accumulation, proteotoxicity and subsequently the onset of several neurodegenerative diseases. Therefore, the targeted and precision-controlled activation of autophagy represents a promising therapeutic strategy. Non-pharmacological therapeutic interventions that delay aging by modulating specific stages of autophagy might be beneficial against premature aging, neurodegeneration and its associated ailments. However, the dynamic and often compensatory cross-talk that exists between the protein degradation pathways makes clinical translational approaches challenging. Here we review the primary autophagy pathways in the context of age-related neurodegenerative diseases, focusing on compensatory mechanisms and pathway failure. By critically assessing each underlying molecular machinery, we reveal their impact on aging and unmask the role of caloric restriction in changing cellular fate by delayed aging through stimulation of autophagy. This may point towards novel and better targeted interventions that exploit the autophagic machinery in the treatment of neurodegenerative diseases. PMID:27473756

  10. Spatio-temporal pattern of vestibular information processing after brief caloric stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Marcelli, Vincenzo [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Esposito, Fabrizio [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Department of Cognitive Neurosciences, University of Maastricht, Maastricht (Netherlands)], E-mail: fabrizio.esposito@unina.it; Aragri, Adriana [Department of Neurological Sciences, Second University of Naples, Naples (Italy); Furia, Teresa; Riccardi, Pasquale [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Tosetti, Michela; Biagi, Laura [I.R.C.S.S. ' Stella Maris' , Pisa (Italy); Marciano, Elio [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Di Salle, Francesco [Department of Cognitive Neurosciences, University of Maastricht, Maastricht (Netherlands); I.R.C.S.S. ' Stella Maris' , Pisa (Italy); Department of Neurosciences, University of Pisa, Pisa (Italy)

    2009-05-15

    Processing of vestibular information at the cortical and subcortical level is essential for head and body orientation in space and self-motion perception, but little is known about the neural dynamics of the brain regions of the vestibular system involved in this task. Neuroimaging studies using both galvanic and caloric stimulation have shown that several distinct cortical and subcortical structures can be activated during vestibular information processing. The insular cortex has been often targeted and presented as the central hub of the vestibular cortical system. Since very short pulses of cold water ear irrigation can generate a strong and prolonged vestibular response and a nystagmus, we explored the effects of this type of caloric stimulation for assessing the blood-oxygen-level-dependent (BOLD) dynamics of neural vestibular processing in a whole-brain event-related functional magnetic resonance imaging (fMRI) experiment. We evaluated the spatial layout and the temporal dynamics of the activated cortical and subcortical regions in time-locking with the instant of injection and were able to extract a robust pattern of neural activity involving the contra-lateral insular cortex, the thalamus, the brainstem and the cerebellum. No significant correlation with the temporal envelope of the nystagmus was found. The temporal analysis of the activation profiles highlighted a significantly longer duration of the evoked BOLD activity in the brainstem compared to the insular cortex suggesting a functional de-coupling between cortical and subcortical activity during the vestibular response.

  11. Spatio-temporal pattern of vestibular information processing after brief caloric stimulation

    International Nuclear Information System (INIS)

    Processing of vestibular information at the cortical and subcortical level is essential for head and body orientation in space and self-motion perception, but little is known about the neural dynamics of the brain regions of the vestibular system involved in this task. Neuroimaging studies using both galvanic and caloric stimulation have shown that several distinct cortical and subcortical structures can be activated during vestibular information processing. The insular cortex has been often targeted and presented as the central hub of the vestibular cortical system. Since very short pulses of cold water ear irrigation can generate a strong and prolonged vestibular response and a nystagmus, we explored the effects of this type of caloric stimulation for assessing the blood-oxygen-level-dependent (BOLD) dynamics of neural vestibular processing in a whole-brain event-related functional magnetic resonance imaging (fMRI) experiment. We evaluated the spatial layout and the temporal dynamics of the activated cortical and subcortical regions in time-locking with the instant of injection and were able to extract a robust pattern of neural activity involving the contra-lateral insular cortex, the thalamus, the brainstem and the cerebellum. No significant correlation with the temporal envelope of the nystagmus was found. The temporal analysis of the activation profiles highlighted a significantly longer duration of the evoked BOLD activity in the brainstem compared to the insular cortex suggesting a functional de-coupling between cortical and subcortical activity during the vestibular response.

  12. Protective effects of estrogens and caloric restriction during aging on various rat testis parameters

    Institute of Scientific and Technical Information of China (English)

    Khaled Hamden; Dorothee Silandre; Christelle Delalande; Abdelfattah ElFek; Serge Carreau

    2008-01-01

    Aim: To investigate the effects of 17β-estradiol (E2), Peganum harmala extract (PHE) and caloric restriction (CR) on various testis parameters during aging. Methods: Twelve-month-old male rats were treated for 6 months with either E2 or PHE, or submitted to CR (40%). Results: Our results show that estrogens and CR are able to protect the male gonad by preventing the decrease of testosterone and E2 levels as well as the decrease of aromatase and estrogen receptor gene expressions. Indeed, E2, PHE and CR treatments induced an increase in the superoxide dismutase activities and decreased the activity of testicular enzymes: gamma-glutamyl transferase, alkaline phosphatase, lactate deshydrogenase as well as the aspartate and lactate transaminases in aged animals. In addition, the testicular catalase and gluthatione peroxidase activities were enhanced in E2, PHE and CR-treated rats compared to untreated animals at 18 months of age. Moreover, the positive effects of estradiol, PHE and CR were further supported by a lower level of lipid peroxidation. Recovery of spermatogenesis was recorded in treated rats. Conclusion: Besides a low caloric diet which is beneficial for spermatogenesis, a protective antioxydant role of estrogens is suggested. Estrogens delay testicular cell damage, which leads to functional senescence and, therefore, estrogens are helpful in protecting the reproductive functions from the adverse effects exerted by reactive oxygen species (ROS) produced in large quanti-ties in the aged testis.

  13. Caloric vestibular stimulation as a treatment for conversion disorder: A case report and medical hypothesis

    Directory of Open Access Journals (Sweden)

    Michael eNoll-Hussong

    2014-06-01

    Full Text Available Conversion disorder is a medical condition in which a person has paralysis, blindness, or other neurological symptoms that cannot be clearly explained physiologically. To date, there is neither specific nor conclusive treatment. In this paper, we draw together a number of disparate pieces of knowledge to propose a novel intervention to provide transient alleviation for this condition. As caloric vestibular stimulation (CVS has been demonstrated to modulate transiently a variety of cognitive functions associated with brain activations, especially in the temporal-parietal cortex, anterior cingulate cortex, and insular cortex, there is evidence to assume an effect in specific mental disorders. Therefore, we go on to hypothesize that lateralized cold vestibular caloric stimulation will be effective in treating conversion disorder and we present provisional evidence from one patient that supports this conclusion. If our hypothesis is correct, this will be the first time in psychiatry and neurology that a clinically well-known mental disorder, long considered difficult to understand and to treat, is relieved by a simple or common, non-invasive medical procedure.

  14. Caloric Restriction Effect on Proinflammatory Cytokines, Growth Hormone, and Steroid Hormone Concentrations during Exercise in Judokas

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    Salma Abedelmalek

    2015-01-01

    Full Text Available The aim of this study was to evaluate the effect of caloric restriction on the immune and hormonal responses during exercise in judo athletes. In a randomised order, 11 male judokas (age: 20.45 ± 0.51; height: 1.71 ± 0.3 m; and body weight: 75.9 ± 3.1 kg participate in this study during a period of weight maintenance (baseline and after 7 days of caloric restriction (CR. All subjects performed the Special Judo Fitness Test (SJFT during the two conditions. Values for nutrient intakes were obtained from a 7 d food record kept during a period of weight maintenance and after a 7-day food restriction (−5~6 MJ/day. Our results showed that CR resulted in significant decreases in body weight (P<0.05 and performance (P<0.05. However, heart rate and SJFT index (P<0.05 increase significantly during CR in comparison to baseline. Moreover, exercise leads to a significant increase in testosterone, cortisol, growth hormone (GH, leukocytes, neutrophils, TNF-α, and IL-6, in both CR and baseline conditions. Compared to baseline, TNF-α and IL-6 were significantly higher during CR condition (P<0.05. Additionally, CR leads to an increase in cortisol and GH (P<0.05 and a decrease in testosterone concentrations (P<0.05.

  15. The calorically restricted ketogenic diet, an effective alternative therapy for malignant brain cancer

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    Zhou Weihua

    2007-02-01

    Full Text Available Abstract Background Malignant brain cancer persists as a major disease of morbidity and mortality in adults and is the second leading cause of cancer death in children. Many current therapies for malignant brain tumors fail to provide long-term management because they ineffectively target tumor cells while negatively impacting the health and vitality of normal brain cells. In contrast to brain tumor cells, which lack metabolic flexibility and are largely dependent on glucose for growth and survival, normal brain cells can metabolize both glucose and ketone bodies for energy. This study evaluated the efficacy of KetoCal®, a new nutritionally balanced high fat/low carbohydrate ketogenic diet for children with epilepsy, on the growth and vascularity of a malignant mouse astrocytoma (CT-2A and a human malignant glioma (U87-MG. Methods Adult mice were implanted orthotopically with the malignant brain tumors and KetoCal® was administered to the mice in either unrestricted amounts or in restricted amounts to reduce total caloric intake according to the manufacturers recommendation for children with refractory epilepsy. The effects KetoCal® on tumor growth, vascularity, and mouse survival were compared with that of an unrestricted high carbohydrate standard diet. Results KetoCal® administered in restricted amounts significantly decreased the intracerebral growth of the CT-2A and U87-MG tumors by about 65% and 35%, respectively, and significantly enhanced health and survival relative to that of the control groups receiving the standard low fat/high carbohydrate diet. The restricted KetoCal® diet reduced plasma glucose levels while elevating plasma ketone body (β-hydroxybutyrate levels. Tumor microvessel density was less in the calorically restricted KetoCal® groups than in the calorically unrestricted control groups. Moreover, gene expression for the mitochondrial enzymes, β-hydroxybutyrate dehydrogenase and succinyl-CoA: 3-ketoacid Co

  16. Mortalidad por hipertermia en Bizkaia durante la ola de calor del verano de 2003: experiencia forense Heat-related mortality in Bizkaia during the Summer 2003 heat wave: Forensic experience

    Directory of Open Access Journals (Sweden)

    B. Morentin

    2004-04-01

    Full Text Available Durante las olas de calor la mortalidad puede incrementar marcadamente, a veces hasta alcanzar proporciones epidémicas, como ha ocurrido en Francia este verano. Según las estadísticas oficiales provisionales en el País Vasco hubo 3 casos de muerte por golpe de calor. Describimos 2 casos de muerte por golpe de calor (hipertermia diagnosticas en el Departamento de Patología Forense de Bizkaia ocurridas durante la ola de calor que azotó a Europa el pasado verano. Ninguna de ellas fue incluida en las estadísticas oficiales provisionales. Se trataba de 2 varones adultos con factores de riesgo: alcoholismo e intoxicación alcohólica en uno y cardiopatía y posible sobreejercicio en el otro. Se describen los resultados de la autopsia que mostraron quemaduras térmicas de 2º grado y hallazgos histopatológicos inespecíficos. El estudio bioquímico de humor vítreo mostró un patrón de deshidratación en uno de ellos. La temperatura rectal fue de 41º C en uno y de 43º C en el otro. Este trabajo demuestra la importancia de la toma de la temperatura rectal y ambiente en situaciones de posible muerte por golpe de calor. El diagnóstico final requiere una valoración integrada de todos los datos circunstanciales, médicos, patológicos y de laboratorio. También subraya la conveniencia de un flujo rápido de la información desde el sistema forense al sistema sanitario encargado de la epidemiología y prevención del golpe de calor en situaciones de alarma.During severe heat waves, like that experienced in the summer of 2003 in southern Europe, mortality can increase sharply, sometimes even acquiring epidemic proportions. According to the provisional official reports in the Basque Country there were 3 deaths by heatstroke. In this article we describe the experience of the Forensic Pathologhy Departament of Bizkaia during the heat wave last summer- Autopsy reports were reviewed. Two deaths were due to heat stroke (fatal hyperthermia, but neither

  17. Bedside Calculation of Energy Expenditure Does Not Guarantee Adequate Caloric Prescription in Long-Term Mechanically Ventilated Critically Ill Patients: A Quality Control Study

    Directory of Open Access Journals (Sweden)

    E. De Waele

    2012-01-01

    Full Text Available Nutrition is essential in critically ill patients, but translating caloric prescriptions into adequate caloric intake remains challenging. Caloric prescriptions (P, effective intake (I, and caloric needs (N, calculated with modified Harris-Benedict formulas, were recorded during seven consecutive days in ventilated patients. Adequacy of prescription was estimated by P/N ratio. I/P ratio assessed accuracy of translating a prescription into administered feeding. I/N ratio compared delivered calories with theoretical caloric needs. Fifty patients were prospectively studied in a mixed medicosurgical ICU in a teaching hospital. Basal and total energy expenditure were, respectively, 1361±171 kcal/d and 1649±233 kcal/d. P and I attained 1536±602 kcal/d and 1424±572 kcal/d, respectively. 24.6% prescriptions were accurate, and 24.3% calories were correctly administered. Excessive calories were prescribed in 35.4% of patients, 27.4% being overfed. Caloric needs were underestimated in 40% prescriptions, with 48.3% patients underfed. Calculating caloric requirements by a modified standard formula covered energy needs in only 25% of long-term mechanically ventilated patients, leaving many over- or underfed. Nutritional imbalance mainly resulted from incorrect prescription. Failure of “simple” calculations to direct caloric prescription in these patients suggests systematic use of more reliable methods, for example, indirect calorimetry.

  18. Caloric Intake from Fast Food among Children and Adolescents in the United States, 2011-2012. NCHS Data Brief. Number 213

    Science.gov (United States)

    Vikraman, Sundeep; Fryar, Cheryl D.; Ogden, Cynthia L.

    2015-01-01

    Consumption of fast food has been linked to weight gain in adults. Fast food has also been associated with higher caloric intake and poorer diet quality in children and adolescents. From 1994 through 2006, caloric intake from fast food increased from 10% to 13% among children aged 2-18 years. This report presents the most recent data on the…

  19. Influencia del Calor Aportado y Metal de Aporte Sobre las Propiedades Mecánicas y la Microestructura de Juntas Soldadas por FCAW de Acero Microaleado de Alta Resistencia

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    César Marconi

    2015-06-01

    Full Text Available ResumenActualmente, los aceros microaleados son ampliamente utilizados en reemplazo de los aceros al C y C-Mn por sus ventajas en cuanto a propiedades mecánicas, resistencia a la corrosión y soldabilidad, permitiendo una reducción de peso de los vehículos y estructuras sin detrimento de su resistencia. Cuando estos aceros son soldados, el ciclo térmico de la soldadura provoca cambios microestructurales que modifican sus propiedades originales. El calor aportado (HI: heat input es una de las principales variables a tener en cuenta cuando se evalúan estas modificaciones. Las propiedades finales de la unión soldada también se definen por el tipo de consumible utilizado. El objetivo de este trabajo es analizar las propiedades mecánicas y la microestructura de juntas soldadas a tope de un acero microaleado con dos grados de metal de aporte y diferentes HI. Como resultado del trabajo se observó un aumento considerable de tamaño de grano en la ZAC adyacente a la línea de fusión para todas las condiciones, siendo este efecto más marcado cuando se soldó con alto HI; y un ablandamiento en la ZAC de grano fino. Prácticamente se mantuvieron los valores de resistencia a la tracción al soldar con ambos consumibles, con un mejor desempeño cuando se soldó con bajo HI. La tenacidad en la ZAC mejoró con la disminución del HI.

  20. Intake of High-intensity Sweeteners alters the Ability of Sweet Taste to Signal Caloric Consequences: Implications for the Learned Control of Energy and Body Weight Regulation

    Science.gov (United States)

    Davidson, Terry L.; Martin, Ashley A.; Clark, Kiely; Swithers, Susan E.

    2012-01-01

    Recent results from both human epidemiological and experimental studies with animals suggest that intake of non-caloric sweeteners may promote, rather than protect against, weight gain and other disturbances of energy regulation. However, without a viable mechanism to explain how consumption of non-caloric sweeteners can increase energy intake and body weight, the persuasiveness of such results has been limited. Using a rat model, the present research showed that intake of non-caloric sweeteners reduces the effectiveness of learned associations between sweet tastes and postingestive caloric outcomes (Experiment 1) and that interfering with this association may impair the ability of rats to regulate their intake of sweet, but not nonsweet, high-fat and high-calorie food (Experiment 2). The results support the hypothesis that consuming noncaloric sweeteners may promote excessive intake and body weight gain by weakening a predictive relationship between sweet taste and the caloric consequences of eating. PMID:21424985

  1. Funcionando con la computadora

    OpenAIRE

    Álvarez, Eduardo; Astiz, Mercedes; Medina, Perla; Montero, Y.; Oliver, María; Rocerau, M. Cristina; Valdez, Guillermo; Vecino, María; Vilanova, Silvia

    2004-01-01

    En este trabajo se presenta la descripción y resultados de la segunda etapa de una experiencia planteada con el objetivo de indagar la manera en que los alumnos determinan e interpretan funciones que explican situaciones problemáticas valiéndose de una nueva forma de trabajo en el aula: la utilización de la computadora como herramienta y un programa asistente matemático. La primera etapa consistió en el desarrollo de un taller optativo con alumnos de entre 14 y 15 años de edad del Colegio Dr....

  2. en pacientes con obesidad

    Directory of Open Access Journals (Sweden)

    Alcia María Alvarado Sánchez

    2005-01-01

    Full Text Available El objetivo de este estudio fue evaluar la eficacia de una intervención psicológica en pacientes con obesidad. Se utilizó un diseño cuasiexperimental con un grupo de estudio y un grupo control. Después de la intervención, se encontró una diferencia significativa en la reducción de peso entre los grupos. Asimismo, hubo un incremento significativo en la autoestima del grupo estudiado.

  3. The effect of prolonged physical activity performed during extreme caloric deprivation on cardiac function.

    Directory of Open Access Journals (Sweden)

    David Planer

    Full Text Available BACKGROUND: Endurance exercise may induce transient cardiac dysfunction. Data regarding the effect of caloric restriction on cardiac function is limited. We studied the effect of physical activity performed during extreme caloric deprivation on cardiac function. METHODS: Thirty-nine healthy male soldiers (mean age 20 ± 0.3 years were studied during a field training exercise lasted 85-103 hours, with negligible food intake and unlimited water supply. Anthropometric measurements, echocardiographic examinations and blood and urine tests were performed before and after the training exercise. RESULTS: Baseline VO(2 max was 59 ± 5.5 ml/kg/min. Participants' mean weight reduction was 5.7 ± 0.9 kg. There was an increase in plasma urea (11.6 ± 2.6 to 15.8 ± 3.8 mmol/L, p<0.001 and urine osmolarity (692 ± 212 to 1094 ± 140 mmol/kg, p<0.001 and a decrease in sodium levels (140.5 ± 1.0 to 136.6 ± 2.1 mmol/L, p<0.001 at the end of the study. Significant alterations in diastolic parameters included a decrease in mitral E wave (93.6 to 83.5 cm/s; p = 0.003, without change in E/A and E/E' ratios, and an increase in iso-volumic relaxation time (73.9 to 82.9 ms, p = 0.006. There was no change in left or right ventricular systolic function, or pulmonary arterial pressure. Brain natriuretic peptide (BNP levels were significantly reduced post-training (median 9 to 0 pg/ml, p<0.001. There was no elevation in Troponin T or CRP levels. On multivariate analysis, BNP reduction correlated with sodium levels and weight reduction (R = 0.8, p<0.001. CONCLUSIONS: Exposure to prolonged physical activity performed under caloric deprivation resulted in minor alterations of left ventricular diastolic function. BNP levels were significantly reduced due to negative water and sodium balance.

  4. Respostas termorregulatórias de crianças no exercício em ambiente de calor Respuestas termorreguladoras de niños en el ejercicio en ambiente de calor Thermoregulatory responses of children exercising in a hot environment

    Directory of Open Access Journals (Sweden)

    Luis Henrique L. S. Gomes

    2013-03-01

    calor. FUENTES DE DATOS: Se realizó una revisión de 47 artículos publicados entre 1960 y 2011 en las bases de datos electrónicas MedLine y SciELO Brasil, con el uso de los siguientes descriptores: "niños", "calor", "sudoración", "termorregulación", "glándula sudorípara" y "ejercicio", siendo usados aisladamente o en combinación, además de una tesis doctoral sobre el tema. SÍNTESIS DE LOS DATOS: En pre-púberes, la tasa de sudoración durante el esfuerzo es menor en comparación a los adultos. Niños poseen características termorreguladoras diferenciadas, presentando un débito de sudor por glándula mucho menor. La mayor razón entre área de superficie y masa corporal hace que los niños absorban más calor durante el ejercicio bajo estrés térmico, elevando el riesgo de presentar síntomas de hipertermia. El mayor flujo de sangre para la piel contribuye con un mejor control de la homeostasis térmica de niños. El menor tamaño de la glándula, la menor sensibilidad colinérgica, los niveles bajos de catecolaminas circulantes durante el esfuerzo y la falta de hormona androgénica explican la ocurrencia de la baja eliminación de sudor en el ejercicio realizado por niños. CONCLUSIONES: Niños exhiben glándulas sudoríparas inmaturas. Así, la práctica de actividad física combinada a altas temperaturas no es bien tolerada por el público infantojuvenil, que presenta mayor vulnerabilidad a las lesiones térmicas. En el calor, se debe tener un control riguroso de la ingestión de líquidos y una monitoración atenta de las condiciones climáticas para mayor seguridad en la práctica de ejercicios.OBJECTIVE: To review possible peculiarities in biological mechanisms related to responses of thermoregulatory and specific sweat glands in exercise performed by children in hot environments. DATA SOURCES: Review of 47 articles published between 1960 and 2011 in the electronic databases MedLine and SciELO Brazil using the following key-words: 'children', 'heat

  5. Comparison of Vestibular Evoked Myogenic Potential and Caloric Tests Findings in Noise Induced Hearing Loss-Affected and Healthy Individuals

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    Farinoosh Fakharnia

    2010-06-01

    Full Text Available Background and Aim: Balance disturbance is one of the non-auditory effects of noisy industrial environments that is usually neglected. The aim of the current study was to investigate the effect of occupational noise on vestibular system among workers with noise-induced hearing loss (NIHL, based on both vestibular evoked myogenic potentials (VEMP and caloric tests.Methods: Thirty male workers with noise-induced hearing loss and thirty male matched controls were examined by VEMP and caloric tests. Study parameters included unilateral weakness, p13 and n23 latencies, and p13-n23 amplitude. Caloric test was performed only for 20 patients.Results: No significant difference was observed in unilateral weakness between the two groups. On the other hand, the difference in mean latencies of p13 in the right ear (p=0.003 and left ear (p=0.01 was significant between the two groups. However, the difference in n23 latency was significant only in the right ear (p=0.03. There was no significant difference between groups in p13-n23 amplitude.Conclusion: It seems that pars inferior of vestibule is the susceptible part in individuals with NIHL. In general, abnormal findings in both VEMP and caloric tests were more common compared to functional symptoms such as vertigo, which may be due to central compensation and the symmetry of the disorder.

  6. A two year randomized controlled trial of human caloric restriction: feasibility and effects on predictors of health span and longevity

    Science.gov (United States)

    Background: Caloric restriction (CR), energy intake reduced below ad libitum (AL) intake, increases life span in many species. The implications for humans can be clarified by randomized controlled trials of CR. Methods: To determine CRs feasibility, safety, and effects on predictors of longevity, di...

  7. Caloric content of leaves of five tree species from the riparian vegetation in a forest fragment from South Brazil

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    Leandro Fabrício Fiori

    2015-09-01

    Full Text Available Abstract Aim: The measurement of the caloric content evidences the amount of energy that remains in the leaf and that can be released to the aquatic trophic chain. We assessed the energy content of leaves from five riparian tree species of a forest fragment in south Brazil and analyzed whether leaf caloric content varied between leaf species and between seasons (dry and wet. The studied sites are located in Northwest of Paraná State, inside a Semi-Deciduous Forest fragment beside two headwater streams. Methods Sampling sites were located along the riparian vegetation of these two water bodies, and due to its proximity and absence of statistical differences of caloric values, analyzed as one compartment. Results Caloric content varied significantly among species and among all pairs of species, with exception of Nectandra cuspidata Ness and Calophyllum brasiliensis Cambess. Two species presented significant differences between seasons, Sloanea guianensis (Aubl. Ben and Calophyllum brasiliensis Cambess. Conclusions The absence of significant seasonal differences of energy content for some species may be due to the characteristics of the tropical forest, in which temperature did not varied dramatically between seasons. However, the energy differed between species and seasons for some species, emphasizing the necessity of a preliminary inspection of energy content, before tracing energy fluxes instead of using a single value to all species from riparian vegetation.

  8. Behavioural changes are a major contributing factor in the reduction of sarcopenia in caloric-restricted ageing mice

    NARCIS (Netherlands)

    Norren, van K.; Rusli, F.; Dijk, van M.; Lute, C.; Nagel, J.C.; Dijk, F.J.; Dwarkasing, J.T.; Boekschoten, M.V.; Luiking, Y.; Witkamp, R.F.; Müller, M.R.; Steegenga, W.T.

    2015-01-01

    Background - In rodent models, caloric restriction (CR) with maintenance of adequate micronutrient supply has been reported to increase lifespan and to reduce age-induced muscle loss (sarcopenia) during ageing. In the present study, we further investigated effects of CR on the onset and severity of

  9. Short-term caloric restriction normalizes hypothalamic neuronal responsiveness to glucose ingestion in patients with type 2 diabetes

    NARCIS (Netherlands)

    Teeuwisse, W.M.; Widya, R.L.; Paulides, M.; Lamb, H.J.; Smit, J.W.A.; Roos, A. de; Buchem, M.A. van; Pijl, H.; Grond, J. van der

    2012-01-01

    The hypothalamus is critically involved in the regulation of feeding. Previous studies have shown that glucose ingestion inhibits hypothalamic neuronal activity. However, this was not observed in patients with type 2 diabetes. Restoring energy balance by reducing caloric intake and losing weight are

  10. Caloric Restriction in Lean and Obese Strains of Laboratory Rat: Effects on Body Composition, Metabolism, Growth, and Overall Health

    Science.gov (United States)

    NEW FINDINGS: What is the central question of this study? How do lean and obese rats respond physiologically to caloric restriction? What is the main finding and its importance? Obese rats show marked benefits compared with lean animals. Reduced body fat is associated with improv...

  11. REHIDRATACIÓN POST-EJERCICIO CON AGUA DE COCO: ¿IGUAL O MÁS EFECTIVA QUE UNA BEBIDA DEPORTIVA?

    OpenAIRE

    Alexandra Pérez Idárraga; Luis Fernando Aragón Vargas

    2011-01-01

    Objetivo: comparar la efectividad rehidratante del agua de coco fresca, con el agua embotellada y una bebida deportiva. Metodología: once participantes de 22,0 ± 1,9 años y 65,6 ± 13,0 kg de masa corporal (promedio ± D.E), asistieron al laboratorio en tres ocasiones, separadas entre sí por una semana. En cada sesión se deshidrataron por ejercicio en el calor hasta perder 1,84 ± 0,2% de la masa corporal. Luego fueron rehidratados en una hora, con agua comercial embotellada (AE), una bebida dep...

  12. Using Light Charged Particles to Probe the Asymmetry Dependence of the Nuclear Caloric Curve

    CERN Document Server

    McIntosh, Alan B; Kohley, Zachary; Cammarata, Paul J; Hagel, Kris; Heilborn, Lauren; Mabiala, Justin; May, Larry W; Marini, Paola; Raphelt, Andrew; Souliotis, George A; Wuenschel, Sara; Zarrella, Andrew; Yennello, Sherry J

    2013-01-01

    Recently, we observed a clear dependence of the nuclear caloric curve on neutron-proton asymmetry $\\frac{N-Z}{A}$ through examination of fully reconstructed equilibrated quasi-projectile sources produced in heavy ion collisions at E/A = 35 MeV. In the present work, we extend our analysis using multiple light charged particle probes of the temperature. Temperatures are extracted with five distinct probes using a kinetic thermometer approach. Additionally, temperatures are extracted using two probes within a chemical thermometer approach (Albergo method). All seven measurements show a significant linear dependence of the source temperature on the source asymmetry. For the kinetic thermometer, the strength of the asymmetry dependence varies with the probe particle species in a way which is consistent with an average emission-time ordering.

  13. Repletion of TNFα or leptin in calorically restricted mice suppresses post-restriction hyperphagia

    Science.gov (United States)

    Hambly, Catherine; Duncan, Jacqueline S.; Archer, Zoë A.; Moar, Kim M.; Mercer, Julian G.; Speakman, John R.

    2012-01-01

    SUMMARY The causes of post-restriction hyperphagia (PRH) represent a target for drug-based therapies to prevent obesity. However, the factors causing PRH are poorly understood. We show that, in mice, the extent of PRH was independent of the time under restriction, but depended on its severity, suggesting that PRH was driven by signals from altered body composition. Signals related to fat mass were important drivers. Circulating levels of leptin and TNFα were significantly depleted following caloric restriction (CR). We experimentally repleted their levels to match those of controls, and found that in both treatment groups the level of PRH was significantly blunted. These data establish a role for TNFα and leptin in the non-pathological regulation of energy homeostasis. Signals from adipose tissue, including but not limited to leptin and TNFα, regulate PRH and might be targets for therapies that support people engaged in CR to reduce obesity. PMID:21954068

  14. Higher Caloric Refeeding Is Safe in Hospitalised Adolescent Patients with Restrictive Eating Disorders

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    Elizabeth K. Parker

    2016-01-01

    Full Text Available Introduction. This study examines weight gain and assesses complications associated with refeeding hospitalised adolescents with restrictive eating disorders (EDs prescribed initial calories above current recommendations. Methods. Patients admitted to an adolescent ED structured “rapid refeeding” program for >48 hours and receiving ≥2400 kcal/day were included in a 3-year retrospective chart review. Results. The mean (SD age of the 162 adolescents was 16.7 years (0.9, admission % median BMI was 80.1% (10.2, and discharge % median BMI was 93.1% (7.0. The mean (SD starting caloric intake was 2611.7 kcal/day (261.5 equating to 58.4 kcal/kg (10.2. Most patients (92.6% were treated with nasogastric tube feeding. The mean (SD length of stay was 3.6 weeks (1.9, and average weekly weight gain was 2.1 kg (0.8. No patients developed cardiac signs of RFS or delirium; complications included 4% peripheral oedema, 1% hypophosphatemia (<0.75 mmol/L, 7% hypomagnesaemia (<0.70 mmol/L, and 2% hypokalaemia (<3.2 mmol/L. Caloric prescription on admission was associated with developing oedema (95% CI 1.001 to 1.047; p=0.039. No statistical significance was found between electrolytes and calories provided during refeeding. Conclusion. A rapid refeeding protocol with the inclusion of phosphate supplementation can safely achieve rapid weight restoration without increased complications associated with refeeding syndrome.

  15. sistema Web con JSP

    Directory of Open Access Journals (Sweden)

    César Viloria Núñez

    2014-01-01

    Full Text Available Este artículo presenta el desarrollo de un sistema de información que permite la adquisición y la administración de información relacionada con los signos vitales como la presión arterial, la frecuencia cardiaca y respiratoria, y la saturación de oxígeno en la sangre de un paciente. La implementación del sistema se basa en una solución Web, permitiendo así que médicos especialistas puedan monitorear a sus pacientes desde cualquier punto conectado a la red en tiempo real y, al mismo tiempo, dar indicaciones críticas al personal médico que se encuentra en el lugar con el paciente.

  16. pacientes con falla cardiaca

    Directory of Open Access Journals (Sweden)

    Diana Marcela Achury Saldaña

    2007-01-01

    Full Text Available Objetivo: determinar la adherencia al tratamiento de pacientes con falla cardiaca hospitalizados, al aplicar un plan educativo quefomenta el autocuidado.Método: estudio cuasiexperimental (entrevistas enfermera-paciente realizado entre diciembre de 2004 y mayo de 2006, con unamuestra de 50 pacientes seleccionados por conveniencia. Se diseñó un instrumento para evaluar los comportamientos de los pacientes,con base en algunos resultados de la adherencia y sus respectivos indicadores de la taxonomía NOC (Nursing out comes classification. Laadherencia al tratamiento fue medida en dos momentos: el primero durante la hospitalización, seguido de la aplicación del plan educativoantes del alta, que proporcionaba información en el manejo de su enfermedad desde una dimensión física, psicológica y social quepromueve el autocuidado; y el segundo un mes después del alta en su domicilio.Resultados: diferencias estadísticamente significativas (P=0,0001 que demuestran cómo mediante la capacitación al paciente enel manejo de su tratamiento farmacológico y no farmacológico, el establecimiento de una sana relación entre el profesional de enfermeríay el paciente, y la participación de la familia, se logra una total adherencia al tratamiento.Conclusiones: para lograr una adherencia total del paciente con falla cardiaca al tratamiento es necesario un proceso educativo y unseguimiento continuo y personalizado que motive permanentemente al paciente y se le reconozca el papel protagónico en su cuidado y manejo de la enfermedad.

  17. Transporte forestal con cables

    OpenAIRE

    Anaya L. Héctor J.

    2012-01-01

    La explotación forestal es un problema fundamentalmente de transporte. El apeo y la preparación de las trozas, aunque a veces presentan algunas dificultades, son operaciones fáciles de resolver comparadas con la operación de transporte la cual absorbe del 60% al 70% o más del costo total del aprovechamiento del bosque. El 30% o 40% restante es absorbido por las faenas previas de apeo y troceo.

  18. Lectura con adolescentes

    Directory of Open Access Journals (Sweden)

    Silvia Méndez Anchía

    2007-01-01

    Full Text Available Con base en la premisa de que la lectura de textos literarios tiene una función formadora y que esta se acentúa en la adolescencia, me propongo demostrar que el cuento “Rapunzel” puede utilizarse como estrategia para explorar algunas situaciones que los sujetos adolescentes perciben como particulares en relación con su vida, pero que se inscriben dentro de grandes problemáticas estudiadas por varias disciplinas. Para ello, he identificado, desde dos marcos de referencia (sociológico y psicoanalítico, diversas problemáticas y discursos que se desprenden de la lectura del cuento realizada por dos mujeres adolescentes, quienes respondieron una guía de lectura y participaron en una entrevista a profundidad. Concluyo que la lectura y comentario del cuento hacen posible que una serie de experiencias que los sujetos adolescentes viven como únicas (como el embarazo de una amiga, las críticas de las personas adultas y las exigencias de padres y madres, ingresen en el circuito de los conocimientos generales al relacionarlas con los discursos y problemáticas en que se inscriben (por ejemplo, el discurso de la “crisis” de la adolescencia, el enfoque de derechos humanos, el mundo fantasmático materno. Por ello, recomiendo la lectura y comentario de textos literarios como estrategia didáctica para contribuir a la elaboración de la subjetividad de personas adolescentes.

  19. Interpretação e utilidade da prova calórica Interpretation and use of caloric testing

    Directory of Open Access Journals (Sweden)

    Denise Utsch Gonçalves

    2008-06-01

    Full Text Available A prova calórica é o teste da avaliação otoneurológica que verifica a integridade do reflexo vestíbulo-ocular e possibilita avaliar cada labirinto separadamente. Os principais aspectos relacionados à realização, interpretação e utilidade da prova calórica foram revistos. MÉTODOS: Realizou-se revisão sistemática sobre as publicações ocorridas nos últimos cem anos sobre o assunto. Incluíram-se artigos originais transversais e longitudinais, de revisão e meta-análise. Excluíram-se revisões de papeleta, relatos de caso e editoriais. Os descritores utilizados foram: prova calórica, nistagmo, sistema vestibular, preponderância direcional, predomínio labiríntico, teste calórico monotermal, teste calórico com água gelada, fenômeno de Bell. Pesquisou-se as bases de dados COCHRAINE, MEDLINE, LILACS, CAPES. RESULTADOS: De 818 resumos de artigos, selecionou-se inicialmente 93 que preenchiam os critérios de inclusão. A leitura dos artigos resultou na seleção final de 55. Na análise dos artigos, enfatizou-se na discussão fundamentos da prova calórica, tipos de estimulação utilizados, prova calórica monotermal e com água gelada, questões relacionadas à interpretação dos resultados, variáveis e artefatos. COMENTÁRIOS FINAIS: os valores de referência utilizados na prova calórica podem variar de serviço para serviço, com ponto de corte definido a partir de estudos locais. Semiotécnica cuidadosa é fundamental para elevar a sensibilidade do exame.Caloric testing is an otoneurologic evaluation of the status of the vestibular-ocular reflex; it allows an evaluation of each labyrinth separately. The main aspects on the use and interpretation of caloric testing are reviewed. METHOD: A systematic review of papers published in the past one hundred years on caloric testing was undertaken. The inclusion criteria were: cross-sectional, longitudinal, original articles, reviews and meta-analyses. Reviews of patient charts

  20. Estudio sobre las propiedades mecánicas de cementos óseos preparados con metacrilatos funcionalizados

    OpenAIRE

    Islas Blancas, M.E.; Cervantes-UC, J.M; Cauich Rodriguez, J.V.

    2000-01-01

    Los cementos óseos son materiales poliméricos que se utilizan con el objeto de fijar prótesis metálicas. Han estado en el mercado por casi 40 años desde que Sir John Charnley propuso su uso en ortopedia. Los cementos óseos convencionales exhiben altos calores de reacción, alta contracción y un elevado contenido de monómero residual; estas propiedades se traducen en un comportamiento mecánico inadecuado y finalmente en el aflojamiento de la prótesis. Nuevas formulaciones hacen uso ...

  1. Comportamiento Termodinámico de un ORC operando con varias sustancias para el aprovechamiento de Fuentes Térmicas de Bajo Potencial

    Directory of Open Access Journals (Sweden)

    Artemio de Jesús Benítez Fundora

    2011-03-01

    Full Text Available En  el  presente  artículo,  se  m uestra  el  estudio  preliminar  relacionado  con  la  selección  y propuesta  de  varios  fluidos  para  operar  un  Ciclo  Rankine  Orgánico  (ORC  con  el  fin  de recuperar el calor de desperdicio de fuentes industriales. El  principal  criterio de selección fue definido  teniendo  en  cuenta  la  temperatura  promedio  de  la  fuente  industrial  de  calor  y  su disponibilidad. Finalmente, son recomendados dos grupos de sustancias para la recuperación de calor de los gases de combustión emitidos por calderas industriales o calentadores a fuego directo; y para efluentes líquidos de una planta industrial, basándose el análisis en la eficiencia obtenida por el ciclo y el nivel de potencia eléctrica generada por el mismo.

  2. High Caloric Diet for ALS Patients: High Fat, High Carbohydrate or High Protein

    Directory of Open Access Journals (Sweden)

    Sarvin Sanaie

    2015-01-01

    . They showed that patients in the highcarbohydrate/high-calorie groups gained 0.39 kg more weight per month, compared with 0.11kg per month in the control group, and there was an average weight loss of 0.46 kg per month in the high-fat/high-calorie group. However, there are some concerns that highcarbohydrate low-fat diets might increase the risk of ALS and these findings should be interpreted with caution (4. Furthermore, according to Wills et al. high fat-high caloric diets could not be ideal regimens for these patients due to the associated gastrointestinal complications (3. Dorst and associates, in their study, showed that high caloric food supplement with high fat is suitable to establish body weight compared to high carbohydrate formula. Hence, it seems that high protein-high caloric diets could be more appropriate options for both improving negative nitrogen balance and decreasing muscle atrophy in patients with ALS based on the pathophysiology of proteinenergy malnutrition and hypermetabolism which is thought to be due to mitochondria problem. The multifactorial pathophysiology of ALS has resulted in hypotheses that there may be subgroups of patients, eventually defined by a specific underlying etiology or clinical presentation, which selectively respond to a particular regimen. Consequently, further RCTs with larger sample size are required to clarify the best regimen for weight gain and improved survival in ALS patients and it seems that personalized nutritional support or combined regimens might be the best way and could improve the quality of life considering the complex pathophysiology of malnutrition.

  3. Heat transformers simulation coupled to industrial processes and experimental evaluation of a thermal transformer of two KW power; Simulacion de transformadores de calor acoplados a procesos industriales y evaluacion experimental de un transformador termico de dos kw de potencia

    Energy Technology Data Exchange (ETDEWEB)

    Cerezo Roman, Jesus

    2001-12-15

    recovering temperature and between 42% and 96% at high temperature for the use of this additives. [Spanish] La quema de combustibles primarios en los diferentes sectores industriales y de transporte, han provocado grandes problemas de salud a la humanidad y contaminacion al medio ambiente, debido principalmente a sus altas emisiones de sustancias y gases, ademas de problemas socioeconomicos en muchos paises. Debido a esto, muchos paises estan investigando nuevas tecnologias alternas para su sustitucion. Uno de los principales tecnologias propuestas son los transformadores de calor. Estos equipos son capaces de ahorrar energia calorifica principalmente en procesos industriales. Debido a esto, estas tesis realiza estudios teoricos de transformadores de calor en procesos industriales tipicos de la region como es la destilacion de derivados de petroleo y refinacion de azucar morena, para observar la energia que puede ser ahorrada por el uso de estos equipos. Por otra parte se realizo una evaluacion experimental de un transformador de calor con aditivos debido a que aumentan la absorcion en el absorbedor, mejorando el coeficiente de operacion. En la simulacion de la columna de destilacion de petroleo se utilizo el simulador de procesos quimicos Aspen Plus version 9.3-2, debido a que este tiene modelos termodinamicos muy confiables para estudiar el comportamiento de cada uno de sus componentes. Los resultados mostraron que con el transformador de calor de una etapa operando con la mezcla LiBr-H{sub 2} O se puede ahorrar hasta un 45% de la energia suministra a la caldera y hasta un 32% con el transformador de doble absorcion. Para la modelacion de la refineria del azucar morena se uso el paquete Visual Basic, version 6.2. El paquete fue utilizado debido a que es un lenguaje grafico y de facil manejo. Los resultados mostraron que se puede recuperar hasta un 15% de la energia suministrada a la caldera. En la experimentacion se utilizo la mezcla bromuro de litio-agua y bromuro de

  4. Metabolic and behavioral compensations in response to caloric restriction: implications for the maintenance of weight loss.

    Directory of Open Access Journals (Sweden)

    Leanne M Redman

    Full Text Available BACKGROUND: Metabolic and behavioral adaptations to caloric restriction (CR in free-living conditions have not yet been objectively measured. METHODOLOGY AND PRINCIPAL FINDINGS: Forty-eight (36.8+/-1.0 y, overweight (BMI 27.8+/-0.7 kg/m(2 participants were randomized to four groups for 6-months; CONTROL: energy intake at 100% of energy requirements; CR: 25% calorie restriction; CR+EX: 12.5% CR plus 12.5% increase in energy expenditure by structured exercise; LCD: low calorie diet (890 kcal/d until 15% weight reduction followed by weight maintenance. Body composition (DXA and total daily energy expenditure (TDEE over 14-days by doubly labeled water (DLW and activity related energy activity (AREE were measured after 3 (M3 and 6 (M6 months of intervention. Weight changes at M6 were -1.0+/-1.1% (CONTROL, -10.4+/-0.9% (CR, -10.0+/-0.8% (CR+EX and -13.9+/-0.8% (LCD. At M3, absolute TDEE was significantly reduced in CR (-454+/-76 kcal/d and LCD (-633+/-66 kcal/d but not in CR+EX or controls. At M6 the reduction in TDEE remained lower than baseline in CR (-316+/-118 kcal/d and LCD (-389+/-124 kcal/d but reached significance only when CR and LCD were combined (-351+/-83 kcal/d. In response to caloric restriction (CR/LCD combined, TDEE adjusted for body composition, was significantly lower by -431+/-51 and -240+/-83 kcal/d at M3 and M6, respectively, indicating a metabolic adaptation. Likewise, physical activity (TDEE adjusted for sleeping metabolic rate was significantly reduced from baseline at both time points. For control and CR+EX, adjusted TDEE (body composition or sleeping metabolic rate was not changed at either M3 or M6. CONCLUSIONS: For the first time we show that in free-living conditions, CR results in a metabolic adaptation and a behavioral adaptation with decreased physical activity levels. These data also suggest potential mechanisms by which CR causes large inter-individual variability in the rates of weight loss and how exercise may

  5. Accumulation of long-chain glycosphingolipids during aging is prevented by caloric restriction.

    Directory of Open Access Journals (Sweden)

    María José Hernández-Corbacho

    Full Text Available BACKGROUND: Chronic kidney disease and end-stage renal disease are major causes of morbidity and mortality that are seen far more commonly in the aged population. Interestingly, kidney function declines during aging even in the absence of underlying renal disease. Declining renal function has been associated with age-related cellular damage and dysfunction with reports of increased levels of apoptosis, necrosis, and inflammation in the aged kidney. Bioactive sphingolipids have been shown to regulate these same cellular processes, and have also been suggested to play a role in aging and cellular senescence. METHODOLOGY/PRINCIPAL FINDINGS: We hypothesized that alterations in kidney sphingolipids play a role in the declining kidney function that occurs during aging. To begin to address this, the sphingolipid profile was measured in young (3 mo, middle aged (9 mo and old (17 mo C57BL/6 male mice. Interestingly, while modest changes in ceramides and sphingoid bases were evident in kidneys from older mice, the most dramatic elevations were seen in long-chain hexosylceramides (HexCer and lactosylceramides (LacCer, with C14- and C16-lactosylceramides elevated as much as 8 and 12-fold, respectively. Increases in long-chain LacCers during aging are not exclusive to the kidney, as they also occur in the liver and brain. Importantly, caloric restriction, previously shown to prevent the declining kidney function seen in aging, inhibits accumulation of long-chain HexCer/LacCers and prevents the age-associated elevation of enzymes involved in their synthesis. Additionally, long-chain LacCers are also significantly elevated in human fibroblasts isolated from elderly individuals. CONCLUSION/SIGNIFICANCE: This study demonstrates accumulation of the glycosphingolipids HexCer and LacCer in several different organs in rodents and humans during aging. In addition, data demonstrate that HexCer and LacCer metabolism is regulated by caloric restriction. Taken together

  6. Funciones con Microsoft Excel

    OpenAIRE

    Castillo, Dalia Imelda; Estrada, Ana Luisa; Hernández, Brenda Amalia

    2009-01-01

    En este documento se presenta el desarrollo de algunas actividades que se trabajaron con estudiantes de primer semestre de la Universidad Autónoma de Nayarit; utilizando la hoja de cálculo Excel en el tema de visualización de funciones, para la materia de lenguaje y pensamiento matemático. Ya que la tecnología ha adquirido un papel muy importante en el proceso enseñanza-aprendizaje, nos ofrece un medio para que el estudiante explore, analice, verifique y desarrolle habilidades que se serán út...

  7. Creo con mis dedos

    OpenAIRE

    S??nchez Aniceto, Monta??a

    2015-01-01

    Las artes pl??sticas son muy importantes para los ni??os/as sobre todo para Educaci??n Infantil ya que promueven la creatividad mediante diferentes recursos y t??cnicas lo que favorece su motivaci??n en las competencias desde la edad temprana hasta la adolescencia. Es la primera forma que tiene el ni??o/a de expresarse en el mundo (a trav??s de los garabatos), de comunicarse, compartir sus emociones con los dem??s, creando su propio lenguaje que evolucionar?? hacia el lenguaje oral y escri...

  8. Mayonesa con quitosano

    OpenAIRE

    Gaffrey, María Celeste

    2014-01-01

    Introducción: El quitosano es un polímero natural que se obtiene a partir de la quitina, la cual forma parte de la estructura de soporte de numerosos organismos vivos, tales como artrópodos (crustáceos e insectos), moluscos y hongos. Presenta propiedades aplicables en los alimentos, como estabilizante, emulsificante, y quelante. No puede ser digerido por los seres humanos por lo cual está considerado como una fibra dietética con un contenido calórico cero. Objetivos: Evaluar...

  9. Eugenistas, pero con prudencia

    Directory of Open Access Journals (Sweden)

    Pogliano, Claudio

    1999-12-01

    Full Text Available Thinking that one could not describe eugenics like a unique movement, since numerous bound varians took place related to the geographical and cultural context, this article tries to demostrate the peculiarity of the Italian case. If already in 1889 Giuseppe Sergi wanted that the artificial selection take it to end what should make the natural, avoiding the risk of the so called «degeneration», only in the face of the First World War seems to grow the alarm for the decadent quality of the population, finding a more and more wide echo. In 1919 the Siges was born (Società italiana de genetica ed eugenica shocked under the impression of the difusse fear about the butcher the war had caused. From there from now on fastens a «nazional» direction closely related to the traditional thought and also with the new political temper. A «moderate» direction, Fascist, Catholic, that was built in consonance with the pronatalism of the regime and in rough polemic with the presumed Anglo-Saxon eugenics aberration.

    Partiendo de la base de que no se puede describir la eugénica como un movimiento unitario, ya que se produjeron numerosas variantes ligadas al contexto geográfico y cultural, este artículo intenta demostrar la peculiaridad del caso italiano. Si ya en 1889 Giuseppe Sergi deseaba que la selección artificial llevase a cabo lo que debía de hacer la natural, evitando así el riesgo de la «degeneración », sólo ante la Primera Guerra Mundial parece crecer la alarma por la decadente calidad de la población, encontrando un eco cada vez más amplio. En 1919 nació la Sige (Società italiana de genetica ed eugenica bajo la impresión del difuso temor que la carnicería bélica había provocado. De ahí en adelante prende rápidamente una dirección «nazional» que se imbrica tanto con una tradición del pensamiento como con el nuevo temple político. Una dirección «moderada» fascista, católica, que se construyó en consonancia con el

  10. Conversando con... BENEDETTA TAGLIABUE

    OpenAIRE

    Torres, Ana; Cabanes, Miguel

    2011-01-01

    Esta entrevista se realiza en el marco del XIII Congreso Internacional de Expresión Gráfica Arquitectónica realizado en la Escuela Técnica Superior de Arquitectura de Valencia los días 27 al 30 de Mayo de 2010.Benedetta Tagliabue es, en la actualidad, una de las arquitectas con mayor prestigio en el panorama internacional. El Pabellón de España para la Expo de Shanghai 2010, es una de sus últimas obras más representativas, en el que se acentúa y desarrolla un conjunto de características arqui...

  11. Aplicación del Método de la Colonia de Hormigas Mixto a la optimización de intercambiadores de calor de tubo y coraza//Application of the Mixed Ant Colony Method to the optimization of tube and shell heat exchangers

    Directory of Open Access Journals (Sweden)

    Maida Bárbara Reyes‐Rodríguez

    2014-05-01

    Full Text Available Los procesos de transferencia de calor sonuno de los problemas más importantes a resolver en el campo de la Ingeniería. Entre los equipos más usados en la industria para realizar la transferencia de calor están los intercambiadores de calor de tubo y coraza. En el presente trabajo se desarrolla el procedimiento para la optimización del diseño de estos equipos utilizando el método de Kern y aplicando el algoritmo de la colonia de hormigas. Se aplica el mismo a tres ejemplos concretos y los resultados obtenidos se comparan con los obtenidos aplicando otros métodos de la inteligencia artificial. Se optimizan los principales parámetros geométricos de los intercambiadores de calor de tubo y coraza para lograr un menor costo de los mismos. Se demuestra la eficacia del nuevo procedimiento MACO (Mixed Ant Colony Optimization, en el proceso de optimización desde el punto de vista económico utilizando diferentes casos de estudios.Palabras claves: intercambiadores de calor, colonia de hormigas, método de Kern.______________________________________________________________________________AbstractHeat transfer processes are one of the most important problems to be solved in the field of Engineering. Among the most widely used equipment for heat transfer in the industry are the shell and tube heat exchangers. This paper develops the procedure for optimizing the design of shell and tube heat exchangers using the method of Kern and applying the ant colony algorithm. The procedure has been applied to three specific examples and the results obtained are compared with those obtained by applying other methods of artificial intelligence. The main geometric parameters of shell and tube heat exchangers are optimized, to achieve a lower cost of the exchanger. The efficacy of the new procedure MACO (Mixed Ant Colony Optimization for the optimization process from economically point of view was demonstrated, using different case studies.Key words: heat

  12. Modeling Isosteric Heat of Soya Bean for Desorption Energy Estimation Using Neural Network Approach Modelación de Calor Isostérico de Soya para Estimación de Energía de Desorción usando Red neural

    Directory of Open Access Journals (Sweden)

    Reza Amiri Chayjan

    2010-12-01

    Full Text Available Sorption isotherm of soya bean (Glycine max (L. Merr. was obtained by the dynamic experimental method. Artificial Neural Networks (ANNs were used for modeling soya bean equilibrium moisture content (EMC. Thermodynamic equations and trained ANN for prediction of two thermodynamic properties of net isosteric heat and entropy of soya bean were utilized. The ANN models were better compared with mathematical models. In this study, the isosteric heat and entropy of sorption of soya bean were separately predicted by two power models as a EMC function. Predictive power of the models was high (R² ≈ 0.99. At the moisture content above 11% (dry basis, db, isosteric heat and entropy of sorption of soya bean were smoothly decreased, while they were highest at moisture content about 8% (db. Isosteric heat and entropy would be useful in the storage simulation of dried soya bean. The ANN model predicts soya bean EMC more accurately than mathematical models. Hence, better equations could be developed for the prediction of heat of sorption and entropy based on data from the ANN model.La isoterma de desorción de soya (Glycine max (L. Merr. se obtuvo por el método experimental dinámico. Se usaron redes neuronales artificiales (ANN para modelación del contenido de humedad de equilibrio (EMC de soya. Se utilizaron ecuaciones termodinámicas y ANN dirigidas para predicción de dos propiedades termodinámicas, calor isostérico neto y entropía de soya. Los modelos ANN fueron mejores comparados con modelos matemáticos. En este estudio, el calor isostérico y entropía de absorción de soya fueron predichas separadamente por dos modelos de poder como una función de EMC. El poder predictivo de los modelos fue alto (R² ≈ 0.99. A un contenido de humedad superior a 11% (db, el calor isostérico y entropía de absorción de soya fueron ligeramente reducidos, y fueron las más altas a un contenido de 8% (db. El calor isostérico y entropía podrían ser útiles en

  13. Better Living through Chemistry: Caloric Restriction (CR) and CR Mimetics Alter Genome Function to Promote Increased Health and Lifespan.

    Science.gov (United States)

    Gillespie, Zoe E; Pickering, Joshua; Eskiw, Christopher H

    2016-01-01

    Caloric restriction (CR), defined as decreased nutrient intake without causing malnutrition, has been documented to increase both health and lifespan across numerous organisms, including humans. Many drugs and other compounds naturally occurring in our diet (nutraceuticals) have been postulated to act as mimetics of caloric restriction, leading to a wave of research investigating the efficacy of these compounds in preventing age-related diseases and promoting healthier, longer lifespans. Although well studied at the biochemical level, there are still many unanswered questions about how CR and CR mimetics impact genome function and structure. Here we discuss how genome function and structure are influenced by CR and potential CR mimetics, including changes in gene expression profiles and epigenetic modifications and their potential to identify the genetic fountain of youth. PMID:27588026

  14. Abdominal obesity, independent from caloric intake, accounts for the development of intestinal tumors in Apc(1638N/+) female mice.

    Science.gov (United States)

    Huffman, Derek M; Augenlicht, Leonard H; Zhang, Xueying; Lofrese, John J; Atzmon, Gil; Chamberland, John P; Mantzoros, Christos S

    2013-03-01

    To determine whether visceral fat (VF), independent of other confounders, is causally linked to intestinal tumorigenesis, we surgically removed visceral fat in Apc(1638/N+) mice. At 15 weeks of age, male and female Apc(1638/N+) mice were randomized to one of three groups: ad libitum, visceral fat removal (VF-) and ad libitum fed, or caloric restriction, and were studied for effects on tumorigenesis and survival. As compared with ad libitum, VF- and caloric restriction reduced macroadenomas to a similar extent (P visceral fat to intestinal cancer risk, and suggest that factors, other than known metabolic mediators, may impact tumor development. Furthermore, these data emphasize that strategies designed to deplete visceral fat stores in humans should be considered in the prevention of intestinal cancer. Cancer Prev Res; 6(3); 177-87. ©2012 AACR. PMID:23466815

  15. Better Living through Chemistry: Caloric Restriction (CR) and CR Mimetics Alter Genome Function to Promote Increased Health and Lifespan

    Science.gov (United States)

    Gillespie, Zoe E.; Pickering, Joshua; Eskiw, Christopher H.

    2016-01-01

    Caloric restriction (CR), defined as decreased nutrient intake without causing malnutrition, has been documented to increase both health and lifespan across numerous organisms, including humans. Many drugs and other compounds naturally occurring in our diet (nutraceuticals) have been postulated to act as mimetics of caloric restriction, leading to a wave of research investigating the efficacy of these compounds in preventing age-related diseases and promoting healthier, longer lifespans. Although well studied at the biochemical level, there are still many unanswered questions about how CR and CR mimetics impact genome function and structure. Here we discuss how genome function and structure are influenced by CR and potential CR mimetics, including changes in gene expression profiles and epigenetic modifications and their potential to identify the genetic fountain of youth. PMID:27588026

  16. Estimativa do fluxo de calor latente pelo balanço de energia em cultivo protegido de pimentão

    OpenAIRE

    Cunha Antonio Ribeiro da; Escobedo João Francisco; Klosowski Elcio Silvério

    2002-01-01

    O objetivo deste trabalho foi caracterizar e relacionar a radiação líquida com o calor latente equivalente, em mm de água, nos cultivos protegido e de campo, na cultura de pimentão. O experimento foi feito em Botucatu, SP. A estimativa do fluxo de calor latente foi feita pelo método do balanço de energia, por meio da razão de Bowen. Foram feitas medidas instantâneas da radiação líquida (Rn), dos fluxos convectivos de calor latente (LE) e sensível (H), do fluxo de calor no solo (G), e dos grad...

  17. con la cosecha mecanizada

    Directory of Open Access Journals (Sweden)

    Arturo Martínez Rodríguez

    2006-01-01

    Full Text Available Las investigaciones dirigidas a incrementar los indicadores de eficiencia y calidad durante la cosecha mecanizada del café, constituyen un tema de gran actualidad a nivel internacional. La determinación de las propiedades físico-mecánicas de los frutos y del sistema frutopedúnculo, es una etapa indispensable durante las investigaciones relacionadas con la cosecha mecanizada de este producto. En este trabajo se brindan los resultados sobre la determinación de un grupo de propiedades dimensionales, inerciales y elásticas del sistema fruto-pedúnculo de coffea arabica variedad Catuai en diferentes estadios de maduración, relacionadas con la cosecha mecanizada de este cultivo.Así mismo se determina el momento flector requerido para la ruptura de la unión fruto pedúnculo. Durante la investigación se emplearon técnicas de procesamiento de imágenes digitales, así como de extensometría eléctrica. Como resultado de la medición de las diferentes propiedades se apreciaron diferencias sustanciales en las características dimensionales, inerciales y elásticas de los frutos maduros y verdes, así como en el momento requerido para el desprendimiento de los frutos y en las formas en que se produce el desprendimiento.

  18. Abdominal obesity, independently from caloric intake, accounts for the development of intestinal tumors in Apc1638N/+ female mice

    OpenAIRE

    Huffman, Derek M.; Augenlicht, Leonard H.; Zhang, Xueying; Lofrese, John J.; Atzmon, Gil; Chamberland, John P.; Mantzoros, Christos S.

    2013-01-01

    To determine whether visceral fat (VF), independent of other confounders, is causally linked to intestinal tumorigenesis, we surgically removed VF in Apc1638/N+ mice. At 15 wks of age, male and female Apc1638/N+ mice were randomized to one of three groups: sham operated (AL), VF removal (VF-), or sham operated and caloric restricted (CR), and were studied for effects on tumorigenesis and survival. As compared to AL, VF removal and CR reduced macroadenomas to a similar extent (P

  19. Early Shifts of Brain Metabolism by Caloric Restriction Preserve White Matter Integrity and Long-Term Memory in Aging Mice

    OpenAIRE

    Janet eGuo; Vikas eBakshi; Ai-Ling eLin

    2015-01-01

    Preservation of brain integrity with age is highly associated with lifespan determination. Caloric restriction (CR) has been shown to increase longevity and healthspan in various species; however, its effects on preserving living brain functions in aging remain largely unexplored. In the study, we used multimodal, non-invasive neuroimaging (PET/MRI/MRS) to determine in vivo brain glucose metabolism, energy metabolites, and white matter structural integrity in young and old mice fed with eithe...

  20. The effect of brand and caloric information on flavor perception and food consumption in restrained and unrestrained eaters.

    Science.gov (United States)

    Cavanagh, Kevin V; Kruja, Blina; Forestell, Catherine A

    2014-11-01

    The goal of the current study was to determine whether provision of brand and caloric information affects sensory perception and consumption of a food in restrained (n=84) and unrestrained eaters (n=104). Using a between-subjects 2 × 2 × 3 design, female restrained and unrestrained eaters were asked to taste and rate a cookie that was labeled with a brand associated with healthful eating (Kashi(®)) or one associated with unhealthful eating (Nabisco(®)). Additionally, some participants were presented with a nutrition label alongside the brand name indicating that one serving contained 130 calories (Low-Calorie Condition), or 260 calories (High-Calorie Condition). The remaining participants were not shown a nutrition label (No Label Condition). Results indicated that those in the No Label or the High-Calorie Condition perceived the healthful branded cookie to have a better flavor than those who received the unhealthful branded cookie regardless of their restraint status. However, restrained eaters in the No Label Condition consumed more of the healthful than the unhealthful branded cookie, whereas those in the Low-Calorie Condition consumed more of the unhealthful than the healthful branded cookie. In contrast, unrestrained eaters ate more of the healthful branded cookie regardless of the caloric information provided. Thus, although restrained and unrestrained eaters' perceptions are similarly affected by branding and caloric information, brands and caloric information interact to affect restrained eaters' consumption. This study reveals that labeling foods as low calorie may create a halo effect which may lead to over-consumption of these foods in restrained eaters.

  1. Effect of replacing sugar with non-caloric sweeteners in beverages on the reward value after repeated exposure.

    Directory of Open Access Journals (Sweden)

    Sanne Griffioen-Roose

    Full Text Available BACKGROUND: The reward value of food is partly dependent on learned associations. It is not yet known whether replacing sugar with non-caloric sweeteners in food is affecting long-term acceptance. OBJECTIVE: To determine the effect of replacing sugar with non-caloric sweeteners in a nutrient-empty drink (soft drink versus nutrient-rich drink (yoghurt drink on reward value after repeated exposure. DESIGN: We used a randomized crossover design whereby forty subjects (15 men, 25 women with a mean ± SD age of 21 ± 2 y and BMI of 21.5 ± 1.7 kg/m(2 consumed a fixed portion of a non-caloric sweetened (NS and sugar sweetened (SS versions of either a soft drink or a yoghurt drink (counterbalanced for breakfast which were distinguishable by means of colored labels. Each version of a drink was offered 10 times in semi-random order. Before and after conditioning the reward value of the drinks was assessed using behavioral tasks on wanting, liking, and expected satiety. In a subgroup (n=18 fMRI was performed to assess brain reward responses to the drinks. RESULTS: Outcomes of both the behavioral tasks and fMRI showed that conditioning did not affect the reward value of the NS and SS versions of the drinks significantly. Overall, subjects preferred the yoghurt drinks to the soft drinks and the ss drinks to the NS drinks. In addition, they expected the yoghurt drinks to be more satiating, they reduced hunger more, and delayed the first eating episode more. Conditioning did not influence these effects. CONCLUSION: Our study showed that repeated consumption of a non-caloric sweetened beverage, instead of a sugar sweetened version, appears not to result in changes in the reward value. It cannot be ruled out that learned associations between sensory attributes and food satiating capacity which developed preceding the conditioning period, during lifetime, affected the reward value of the drinks.

  2. Estudio de la transferencia de calor en la etapa de cocido en la elaboración de aceitunas verdes al estilo sevillano

    Directory of Open Access Journals (Sweden)

    Tarrado-Castellarnau, M.

    2013-09-01

    Full Text Available This article describes for the first time at the industrial level the temperature rise that occurs inside the processing tank during the lye treatment. Relationships between variables that define the lye treatment have been determined from the study of the thermal characteristics of this process. The initial temperature influences other variables of this treatment, such as its duration or the slope of the linear increase of temperature produced. The study estates that this generation of heat can be principally caused by the alkaline hydrolysis reactions that occur in the interior of the fruit and, to a lesser extent, by the dilution of sodium hydroxide solution with water present in the pulp of the olives.En este artículo se describe por primera vez a nivel industrial el aumento de temperatura que se produce en el interior de los tanques de elaboración durante la etapa de cocido. A partir del estudio de las características térmicas de la etapa de cocido se han podido determinar relaciones entre las variables que definen el proceso. Se ha demostrado que la temperatura al inicio del tratamiento de cocido influye en otras de las características del proceso como la duración de éste o la pendiente del aumento lineal de temperatura durante la etapa. El estudio establece que esta generación de calor puede provenir principalmente de las reacciones de hidrólisis alcalina que ocurren en el interior del fruto y, en menor proporción, de la dilución de la solución de hidróxido de sodio con el agua presente en la pulpa de las aceitunas.

  3. Caloric Restriction Eliminates the Aging-related Declines of NMDA and AMPA Receptor Subunits in the Rat Hippocampus and Induces Homeostasis

    OpenAIRE

    Shi, Lei; Adams, Michelle M.; Linville, M. Constance; Newton, Isabel G.; Forbes, M. Elizabeth; Long, Ashley; Riddle, David R.; Brunso-Bechtold, Judy K.

    2007-01-01

    Caloric restriction (CR) extends lifespan and ameliorates the aging-related decline in hippocampal-dependent cognitive function. In the present study, we compared subunit levels of NMDA and AMPA types of the glutamate receptor and quantified total synapses and multiple spine bouton (MSB) synapses in hippocampal CA1 from young (10 months), middle-aged (18 months), and old (29 months) Fischer 344 x Brown Norway rats that were ad libitum (AL) fed or caloric restricted (CR) from 4 months of age. ...

  4. Eliminación del Biofouling en intercambiadores de calor-condensadores que minimicen el impacto ambiental en el medio marino

    OpenAIRE

    Río Calonge, Belén

    2011-01-01

    RESUMEN: La presente tesis doctoral tiene por objeto tratar de eliminar el fenómeno no deseable de formación de biofouling en diferentes superficies tubulares de intercambiadores de calor, mediante tratamientos físicos y químicos, intentando minimizar el impacto ambiental creado en los efluentes de las instalaciones industriales. El equipo experimental está compuesto por una planta piloto de intercambiadores de calor condensadores dotada de ocho tubos que funcionan como sistemas independie...

  5. Maintenance of cellular ATP level by caloric restriction correlates chronological survival of budding yeast

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Joon-Seok; Lee, Cheol-Koo, E-mail: cklee2005@korea.ac.kr

    2013-09-13

    Highlights: •CR decreases total ROS and mitochondrial superoxide during the chronological aging. •CR does not affect the levels of oxidative damage on protein and DNA. •CR contributes extension of chronological lifespan by maintenance of ATP level -- Abstract: The free radical theory of aging emphasizes cumulative oxidative damage in the genome and intracellular proteins due to reactive oxygen species (ROS), which is a major cause for aging. Caloric restriction (CR) has been known as a representative treatment that prevents aging; however, its mechanism of action remains elusive. Here, we show that CR extends the chronological lifespan (CLS) of budding yeast by maintaining cellular energy levels. CR reduced the generation of total ROS and mitochondrial superoxide; however, CR did not reduce the oxidative damage in proteins and DNA. Subsequently, calorie-restricted yeast had higher mitochondrial membrane potential (MMP), and it sustained consistent ATP levels during the process of chronological aging. Our results suggest that CR extends the survival of the chronologically aged cells by improving the efficiency of energy metabolism for the maintenance of the ATP level rather than reducing the global oxidative damage of proteins and DNA.

  6. Entropy Generation and Human Aging: Lifespan Entropy and Effect of Diet Composition and Caloric Restriction Diets

    Directory of Open Access Journals (Sweden)

    Carlos A. Silva

    2009-01-01

    Full Text Available The first and second laws of thermodynamic were applied to statistical databases on nutrition and human growth in order to estimate the entropy generation over the human lifespan. The calculations were performed for the cases of variation in the diet composition and calorie restriction diets; and results were compared to a base case in which lifespan entropy generation was found to be 11 404 kJ/K per kg of body mass, predicting a lifespan of 73.78 and 81.61 years for the average male and female individuals respectively. From the analysis of the results, it was found that changes of diet % of fat and carbohydrates do not have a significant impact on predicted lifespan, while the diet % of proteins has an important effect. Reduction of diet protein % to the minimum recommended in nutrition literature yields an average increase of 3.3 years on the predicted lifespan. Changes in the calorie content of the diet also have an important effect, yielding a % increase in lifespan equal or higher than the % reduction in the diet caloric content. This correlates well experimental data on small mammal and insects, in which lifespan has been increased by diet restriction.

  7. Evaluation of dysphagia risk, nutritional status and caloric intake in elderly patients with Alzheimer's

    Directory of Open Access Journals (Sweden)

    Vanessa Fernanda Goes

    2014-04-01

    Full Text Available OBJECTIVE: to evaluate the risk of dysphagia and its relationship with the stage of Alzheimer's Disease, as well as the relationship between the risk of dysphagia and nutritional status and caloric intake in elderly people with Alzheimer's disease.METHODS: the sample consisted of 30 subjects of both genders with probable Alzheimer's disease. The stage of the disease, nutritional status, energy intake, and risk of dysphagia were assessed.RESULTS: it was found that increased risk of dysphagia is associated with the advance in the stages of Alzheimer's disease and that even patients in the early stages of disease have a slight risk of developing dysphagia. No association was found between nutritional status and the risk of dysphagia. High levels of inadequate intake of micronutrients were also verified in the patients.CONCLUSION: an association between dysphagia and the development of Alzheimer's disease was found. The results indicate the need to monitor the presence of dysphagia and the micronutrient intake in patients with Alzheimer's disease.

  8. Sexually dimorphic responses to fat loss after caloric restriction or surgical lipectomy.

    Science.gov (United States)

    Shi, Haifei; Strader, April D; Woods, Stephen C; Seeley, Randy J

    2007-07-01

    White adipose tissue is the principal site for lipid accumulation. Males and females maintain distinctive white adipose tissue distribution patterns. Specifically, males tend to accumulate relatively more visceral fat, whereas females accumulate relatively more subcutaneous fat. The phenomenon of maintaining typical sex-specific fat distributions suggests sex-specific mechanisms that regulate energy balance and adiposity. We used two distinct approaches to reduce fat mass, caloric restriction (CR), and surgical fat removal (termed lipectomy) and assessed parameters involved in the regulation of energy balance. We found that male and female mice responded differentially to CR- and to lipectomy-induced fat loss. Females decreased energy expenditure during CR or after lipectomy. In contrast, males responded by eating more food during food return after CR or after lipectomy. Female CR mice conserved subcutaneous fat, whereas male CR mice lost adiposity equally in the subcutaneous and visceral depots. In addition, female mice had a reduced capability to restore visceral fat after fat loss. After CR, plasma leptin levels decreased in male but not in female mice. The failure to increase food intake after returning to ad libitum intake in females could be due to the relatively stable levels of leptin. In summary, we have found sexual dimorphisms in the response to fat loss that point to important underlying differences in the strategies by which male and female mice regulate body weight. PMID:17426110

  9. Maintenance of cellular ATP level by caloric restriction correlates chronological survival of budding yeast

    International Nuclear Information System (INIS)

    Highlights: •CR decreases total ROS and mitochondrial superoxide during the chronological aging. •CR does not affect the levels of oxidative damage on protein and DNA. •CR contributes extension of chronological lifespan by maintenance of ATP level -- Abstract: The free radical theory of aging emphasizes cumulative oxidative damage in the genome and intracellular proteins due to reactive oxygen species (ROS), which is a major cause for aging. Caloric restriction (CR) has been known as a representative treatment that prevents aging; however, its mechanism of action remains elusive. Here, we show that CR extends the chronological lifespan (CLS) of budding yeast by maintaining cellular energy levels. CR reduced the generation of total ROS and mitochondrial superoxide; however, CR did not reduce the oxidative damage in proteins and DNA. Subsequently, calorie-restricted yeast had higher mitochondrial membrane potential (MMP), and it sustained consistent ATP levels during the process of chronological aging. Our results suggest that CR extends the survival of the chronologically aged cells by improving the efficiency of energy metabolism for the maintenance of the ATP level rather than reducing the global oxidative damage of proteins and DNA

  10. Efficient gasification of wet biomass residue to produce middle caloric gas

    Institute of Scientific and Technical Information of China (English)

    Guangwen Xu; Takahiro Murakami; Toshiyuki Suda; Hidehisa Tani; Yutaka Mito

    2008-01-01

    Various process residues represent a kind of biomass resource already concentrated but containing water as much as 60 wt.%.These materials are generally treated as waste or simply combusted directly to generate heat.Recently,we attempted to convert them into middle caloric gas to substitute for natural gas,as a chemical or a high-rank gaseous fuel for advanced combustion utilities.Such conversion is implemented through dual fluidized bed gasification (DFBG).Concerning the high water content of the fuels,DFBG was suggested to accomplish either with high-efficiency fuel drying in advance or direct decoupling of fuel drying/pyrolysis from char gasification and tar/hydrocarbon reforming.Along with fuel drying,calcium-based catalyst can be impregnated into the fuel,without much additional cost,to increase the fuel's gasification reactivity and to reduce tar formation.This article reports the Ca impregnation method and its resulting effects on gasification reactivity and tar suppression ability.Meanwhile,the principle of directly gasifying wet fuel with decoupled dual fluidized bed gasification (D-DFBG) is also highlighted.

  11. The 'balance intervention' for promoting caloric compensatory behaviours in response to overeating: a formative evaluation.

    Science.gov (United States)

    Wammes, Birgitte; Breedveld, Boudewijn; Kremers, Stef; Brug, Johannes

    2006-08-01

    To help people prevent weight gain, the Netherlands Nutrition Centre initiated the 'balance intervention', which promotes moderation of food intake and/or increased physical activity in response to occasions of overeating. The aim of this study was to determine whether intervention materials were appreciated, encouraged information seeking and increased motivation and caloric compensatory behaviours. A three-group randomized trial with pre-intervention measures (n = 963, response 86%) and post-intervention measures (n = 857) using electronic questionnaires was conducted among participants aged 25-40 years, recruited from an Internet research panel. The first group received a printed brochure and electronic newsletters (print group), the second group was exposed to radio advertisements (radio group) and the third group was the control group. Multiple regression analyses were used to investigate the impact of the materials on self-reported prevalence of overeating, attitudes, perceived behavioural control, intentions and compensatory behaviours. At follow-up, we found significantly more positive attitudes, intentions and dietary action in the print and radio groups. However, participants who received the radio advertisement had a significantly lower perceived behavioural control. No effects were found on the prevalence of overeating. The results indicate that the intervention materials have potential for increasing people's attitudes, motivation and self-reported behaviour actions, with a possible negative side-effect on perceived behavioural control. PMID:16606638

  12. Non-Invasive Neuromodulation Using Time-Varying Caloric Vestibular Stimulation

    Science.gov (United States)

    Rogers, Lesco L.; Ade, Kristen K.; Nicoletto, Heather A.; Adkins, Heather D.; Laskowitz, Daniel T.

    2016-01-01

    Caloric vestibular stimulation (CVS) to elicit the vestibulo-ocular reflex has long been used in clinical settings to aid in the diagnosis of balance disorders and to confirm the absence of brainstem function. While a number of studies have hinted at the potential therapeutic applications of CVS, the limitations of existing devices have frustrated that potential. Current CVS irrigators use water or air during short-duration applications; however, this approach is not tenable for longer duration therapeutic protocols or home use. Here, we describe a solid-state CVS device we developed in order to address these limitations. This device delivers tightly controlled time-varying thermal waveforms, which can be programmed through an external control unit. It contains several safety features, which limit patients to the prescribed waveform and prevent the potential for temperature extremes. In this paper, we provide evidence that CVS treatment with time-varying, but not constant temperature waveforms, elicits changes in cerebral blood flow physiology consistent with the neuromodulation of brainstem centers, and we present results from a small pilot study, which demonstrate that the CVS can safely and feasibly be used longitudinally in the home setting to treat episodic migraine. Together, these results indicate that this solid-state CVS device may be a viable tool for non-invasive neuromodulation. PMID:27777829

  13. Manipulation of health span and function by dietary caloric restriction mimetics.

    Science.gov (United States)

    Roth, George S; Ingram, Donald K

    2016-01-01

    After nearly a century of rigorous investigation and testing, dietary caloric restriction (CR) remains the most robust and reproducible method for slowing aging and maintaining health, function, and vitality. This intervention has been applied to species across the evolutionary spectrum, but for a number of reasons, practical applicability to humans has been questioned. To overcome these issues, we initiated the field of CR mimetics in 1998 and have observed its development into a full-fledged antiaging industry. Basically, strategies that enable individuals to obtain the biological benefits of CR without reducing actual food intake can be considered CR mimetics, whether functional, pharmaceutical, nutraceutical, or other. Some of the best known candidates include resveratrol and related agents, the antidiabetic drug metformin, and rapamycin and other mTOR regulators. While the mechanisms of action vary, these and essentially all CR mimetic candidates work through at least some of the same pathways as actual CR. While the entire field continues to evolve rapidly, the current status will be reviewed here, with particular focus on recent developments, the most practical relevance and applicability for potential consumers, and new strategies for the future. PMID:26214681

  14. Whole-transcriptome analysis of mouse adipose tissue in response to short-term caloric restriction.

    Science.gov (United States)

    Kim, Seung-Soo; Choi, Kyung-Mi; Kim, Soyoung; Park, Taesun; Cho, In-Cheol; Lee, Jae-Won; Lee, Cheol-Koo

    2016-04-01

    Caloric restriction (CR) has been shown to extend the lifespan of many species by improving cellular function and organismal health. Additionally, fat reduction by CR may play an important role in lengthening lifespan and preventing severe age-related diseases. Interestingly, CR induced the greatest transcriptome change in the epididymal fat of mice in our study. In this transcriptome analysis, we identified and categorized 446 genes that correlated with CR level. We observed down-regulation of several signaling pathways, including insulin/insulin-like growth factor 1 (insulin/IGF-1), epidermal growth factor (EGF), transforming growth factor beta (TGF-β), and canonical wingless-type mouse mammary tumor virus integration site (Wnt). Many genes related to structural features, including extracellular matrix structure, cell adhesion, and the cytoskeleton, were down-regulated, with a strong correlation to the degree of CR. Furthermore, genes related to the cell cycle and adipogenesis were down-regulated. These biological processes are well-identified targets of insulin/IGF-1, EGF, TGF-β, and Wnt signaling. In contrast, genes involved in specific metabolic processes, including the tricarboxylic acid cycle and the electron transport chain were up-regulated. We performed in silico analysis of the promoter sequences of CR-responsive genes and identified two associated transcription factors, Paired-like homeodomain 2 (Pitx2) and Paired box gene 6 (Pax6). Our results suggest that strict regulation of signaling pathways is critical for creating the optimal energy homeostasis to extend lifespan.

  15. Measuring aging rates of mice subjected to caloric restriction and genetic disruption of growth hormone signaling

    Science.gov (United States)

    Koopman, Jacob J.E.; van Heemst, Diana; van Bodegom, David; Bonkowski, Michael S.; Sun, Liou Y.; Bartke, Andrzej

    2016-01-01

    Caloric restriction and genetic disruption of growth hormone signaling have been shown to counteract aging in mice. The effects of these interventions on aging are examined through age-dependent survival or through the increase in age-dependent mortality rates on a logarithmic scale fitted to the Gompertz model. However, these methods have limitations that impede a fully comprehensive disclosure of these effects. Here we examine the effects of these interventions on murine aging through the increase in age-dependent mortality rates on a linear scale without fitting them to a model like the Gompertz model. Whereas these interventions negligibly and non-consistently affected the aging rates when examined through the age-dependent mortality rates on a logarithmic scale, they caused the aging rates to increase at higher ages and to higher levels when examined through the age-dependent mortality rates on a linear scale. These results add to the debate whether these interventions postpone or slow aging and to the understanding of the mechanisms by which they affect aging. Since different methods yield different results, it is worthwhile to compare their results in future research to obtain further insights into the effects of dietary, genetic, and other interventions on the aging of mice and other species. PMID:26959761

  16. Higher Caloric Refeeding Is Safe in Hospitalised Adolescent Patients with Restrictive Eating Disorders

    Science.gov (United States)

    Parker, Elizabeth K.; Faruquie, Sahrish S.; Anderson, Gail; Gomes, Linette; Kennedy, Andrew; Wearne, Christine M.; Kohn, Michael R.; Clarke, Simon D.

    2016-01-01

    Introduction. This study examines weight gain and assesses complications associated with refeeding hospitalised adolescents with restrictive eating disorders (EDs) prescribed initial calories above current recommendations. Methods. Patients admitted to an adolescent ED structured “rapid refeeding” program for >48 hours and receiving ≥2400 kcal/day were included in a 3-year retrospective chart review. Results. The mean (SD) age of the 162 adolescents was 16.7 years (0.9), admission % median BMI was 80.1% (10.2), and discharge % median BMI was 93.1% (7.0). The mean (SD) starting caloric intake was 2611.7 kcal/day (261.5) equating to 58.4 kcal/kg (10.2). Most patients (92.6%) were treated with nasogastric tube feeding. The mean (SD) length of stay was 3.6 weeks (1.9), and average weekly weight gain was 2.1 kg (0.8). No patients developed cardiac signs of RFS or delirium; complications included 4% peripheral oedema, 1% hypophosphatemia (refeeding syndrome. PMID:27293884

  17. Practical system for the direct measurement of magneto-caloric effect by micro-thermocouples.

    Science.gov (United States)

    Kamarád, J; Kaštil, J; Arnold, Z

    2012-08-01

    A system for direct measurements of the magneto-caloric effect (MCE) exploits a rapid transport of a sample into or from magnetic field in permanent Halbach-type (1 T) or superconducting (4.7 T) magnets. Time dependence of induced changes of the sample temperature, ΔT(t), is detected directly by the differential Cu-Constantan-Cu micro-thermocouples with time steps of 300 ms. A sample placed inside an evacuated simple LN(2) cryostat is either totally isolated (adiabatic conditions) or partly connected with the copper sample holder (non-adiabatic conditions). The last arrangement (a model of the Brayton cycle) is used to simulate an application of MCE in refrigeration techniques. The relations describing ΔT(t) that allow an analysis of MCE of the studied materials are based on the general cooling law. The effect of the first-order magnetic transition on MCE of selected sample is also demonstrated by non-standard ΔT(t) curves measured in the last mentioned experimental arrangements. PMID:22938309

  18. Trombose induzida pelo calor endovenoso: relato de dois casos tratados com rivaroxabana e revisão da literatura

    Directory of Open Access Journals (Sweden)

    Walter Junior Boim de Araujo

    2016-01-01

    Full Text Available Resumo Define-se trombose induzida pelo calor endovenoso como a propagação do trombo a partir de uma veia superficial em direção a uma veia mais profunda. Em geral, é considerada clinicamente insignificante quando não há propagação do trombo para o sistema venoso profundo. Essa condição pode ser tratada com terapia anticoagulante, embora a observação pareça ser suficiente, principalmente para graus menores. Neste estudo, relatamos dois casos de trombose induzida pelo calor endovenoso que teriam indicação de heparina de baixo peso molecular até a resolução do quadro. Porém, optou-se pelo uso da rivaroxabana (15 mg de 12 em 12h, com resolução completa do trombo em 4 semanas (caso 1 e em 7 dias (caso 2. A rivaroxabana pode ser uma alternativa promissora no tratamento da trombose induzida pelo calor endovenoso avançada, pela simplicidade da posologia, sem comprometimento da eficácia ou da segurança. São necessários estudos prospectivos, randomizados e controlados que possibilitem melhor entendimento da condição e o desenvolvimento de recomendações mais definitivas sobre opções de prevenção e tratamento.

  19. Caloric Intake on the Sabbath: A Pilot Study of Contributing Factors to Obesity in the Orthodox Jewish Community.

    Science.gov (United States)

    Rosenberg, Deborah A; Swencionis, Charles; Segal-Isaacson, C J

    2016-10-01

    The American Orthodox Jewish community has specific cultural factors that may contribute to overweight and obesity. This study aimed to look at caloric intake on the Sabbath and its contribution to overweight and obesity. Twelve married or previously married women who identify themselves as Orthodox Jews were recruited to do 24-h food recalls over the phone. The participants were divided into three weight groups (normal, overweight, and obese) based on their BMI. The overweight and obese participants' data were combined into one group for the purposes of statistical testing. Paired t tests looking at the data for all participants showed significantly great caloric intake during an average Sabbath day than an average weekday [t(4) = 7.58, p obese women compared to the normal weight women [F(1) = 7.83, p = 0.02]. No statistical difference was seen between the weekday energy intake of the normal weight women as compared to the combined group of overweight-obese women [F(1) = 0.501, p = 0.499]. These results support the hypotheses that all groups eat significantly more on the Sabbath than on weekdays, and overweight and obese individuals eat significantly more on the Sabbath than normal weight individuals. This supports the theory that caloric intake on the Sabbath is a contributing factor to overweight and obesity within the American Orthodox Jewish community. PMID:26613588

  20. Extension of Drosophila Lifespan by Rhodiola rosea Depends on Dietary Carbohydrate and Caloric Content in a Simplified Diet.

    Science.gov (United States)

    Schriner, Samuel E; Coskun, Volkan; Hogan, Sean P; Nguyen, Cindy T; Lopez, Terry E; Jafari, Mahtab

    2016-03-01

    The root and rhizome extract of Rhodiola rosea has been extensively used in traditional medicine to improve physical and mental performance and to protect against stress. We, and others, have reported that R. rosea can extend lifespan in flies, worms, and yeast. We also previously found that the extract can act independently of dietary restriction (DR), a treatment that can extend lifespan in a range of model organisms. In flies, DR is implemented through a reduction in dietary yeast content. Here, we report that the ability of R. rosea extract to extend lifespan in flies is dependent on the carbohydrate and caloric content when supplemented with a simplified diet composed of yeast and sucrose. R. rosea extract elevated the sugar content in flies and down-regulated hexokinase expression, suggesting that it perturbs carbohydrate metabolism in flies. In our previous studies, bananas, barley malt, and corn syrup provided dietary carbohydrates, and R. rosea extract could extend lifespan with a range of caloric levels. We conclude that the lifespan-extending effect of R. rosea extract in flies is dependent on dietary carbohydrate and caloric contents coupled with an interaction with complex dietary components present in bananas, barley, or corn. PMID:26987024

  1. Caloric Intake on the Sabbath: A Pilot Study of Contributing Factors to Obesity in the Orthodox Jewish Community.

    Science.gov (United States)

    Rosenberg, Deborah A; Swencionis, Charles; Segal-Isaacson, C J

    2016-10-01

    The American Orthodox Jewish community has specific cultural factors that may contribute to overweight and obesity. This study aimed to look at caloric intake on the Sabbath and its contribution to overweight and obesity. Twelve married or previously married women who identify themselves as Orthodox Jews were recruited to do 24-h food recalls over the phone. The participants were divided into three weight groups (normal, overweight, and obese) based on their BMI. The overweight and obese participants' data were combined into one group for the purposes of statistical testing. Paired t tests looking at the data for all participants showed significantly great caloric intake during an average Sabbath day than an average weekday [t(4) = 7.58, p Sabbath for the overweight-obese women compared to the normal weight women [F(1) = 7.83, p = 0.02]. No statistical difference was seen between the weekday energy intake of the normal weight women as compared to the combined group of overweight-obese women [F(1) = 0.501, p = 0.499]. These results support the hypotheses that all groups eat significantly more on the Sabbath than on weekdays, and overweight and obese individuals eat significantly more on the Sabbath than normal weight individuals. This supports the theory that caloric intake on the Sabbath is a contributing factor to overweight and obesity within the American Orthodox Jewish community.

  2. Nonnutritive, Low Caloric Substitutes for Food Sugars: Clinical Implications for Addressing the Incidence of Dental Caries and Overweight/Obesity

    Directory of Open Access Journals (Sweden)

    Michael W. Roberts

    2012-01-01

    Full Text Available Caries and obesity are two common conditions affecting children in the United States and other developed countries. Caries in the teeth of susceptible children have often been associated with frequent ingestion of fermentable sugars such as sucrose, fructose, glucose, and maltose. Increased calorie intake associated with sugars and carbohydrates, especially when associated with physical inactivity, has been implicated in childhood obesity. Fortunately, nonnutritive artificial alternatives and non-/low-caloric natural sugars have been developed as alternatives to fermentable sugars and have shown promise in partially addressing these health issues. Diet counseling is an important adjunct to oral health instruction. Although there are only five artificial sweeteners that have been approved as food additives by the Food and Drug Administration (FDA, there are additional five non-/low caloric sweeteners that have FDA GRAS (Generally Recognized as Safe designation. Given the health impact of sugars and other carbohydrates, dental professionals should be aware of the nonnutritive non-/low caloric sweeteners available on the market and both their benefits and potential risks. Dental health professionals should also be proactive in helping identify patients at risk for obesity and provide counseling and referral when appropriate.

  3. Entrevista con Juan Marichal.

    Directory of Open Access Journals (Sweden)

    - Consejo de Redacción

    1997-01-01

    Full Text Available Juan Marichal nació en Santa Cruz de Tenerife, en 1922, en el seno de una familia ligada al partido republicano insular. Muy joven, en 1935, se trasladó a Madrid, ciudad en la que vive el estallido de la guerra civil. En 1937, pasa a Valencia y luego a Barcelona; tras su exilio en 1938, prosigue sus estudios secundarios en un liceo de París, concluyéndolos en Casablanca. En 1941 emigra a México, formándose en la UNAM: fue alumno de los exiliados José Gaos y Joaquín Xirau así como del mexicano Edmundo O 'Gorman. Luego, becado en Princeton desde 1946, lo fue de América Castro, donde preparó una tesis sobre Feijoo. Apoyado en las vastas perspectivas de sus maestros, fue orientándose hada nuestra historia intelectual, desde el siglo XV hasta hoy. Su carrera profesional se ha desarrollado en los Estados Unidos (coincidiendo con Amado Alonso y con Ferrater Mora: ha sido profesor de estudios hispánicos en la Universidad de Harvard, desde 1948 hasta 1988, año en que se jubiló voluntariamente como numerario (aunque había permanecido en el Bryn Mawr College, entre 1953 y 1957. A este trabajo se suman, con todo, sus conferencias en América Latina y en España. Ha colaborado en las revistas más importantes, en este campo, de México, Nueva York, Puerto Rico, La Habana, Buenos Aires o París así como de las españolas, desde los sesenta. Juan Marichal -hoy, miembro de la Junta Directiva de los Amigos de la Residencia de Estudiantes, director del Boletín de la Institución Libre de Enseñanza y asociado al Instituto Universitario Ortega y Gasset-, reside en España desde otoño de 1989: se considera a sí mismo «voluntario en Madrid», como había dicho Alfonso Reyes en su estancia madrileña (1914-1924.

  4. Aprendiendo a cuidar al recién nacido: un cuidado congruente con la cultura

    Directory of Open Access Journals (Sweden)

    NORMA YANETH NOGUERA ORTIZ

    2008-07-01

    Full Text Available El presente artículo es resultado del trabajo de grado para optar al título como Enfermera Especialista en Enfermería Materno Perinatal, el cual tuvo como propósito realizar una propuesta de cuidado de enfermería al recién nacido desde lo cultural, con base en las prácticas de cuidado que las madres adolescentes realizan con sus hijos durante la etapa de puerperio. Dicha propuesta se desarrolló a partir de los resultados obtenidos en la investigación "Prácticas de cuidado que las madres adolescentes realizan con sus hijos recién nacidos durante la etapa de puerperio" llevada a cabo por Nancy Lucía Bejarano y otros, en el año 2002 (1, en dos ciudades de Colombia con altas tasas de fecundidad. La propuesta de cuidado se diseñó a partir de un estudio exploratorio, descriptivo y documental con abordaje cualitativo, pues se tuvo en cuenta la investigación base, la recolección y la revisión de la bibliografía. Esta propuesta se ocupa de las prácticas de cuidado relacionadas con dos dominios encontrados en la investigación base: 1 favorecer el cierre de las aberturas transitorias con que llega el recién nacido y 2 evitar la entrada de frío y calor para la búsqueda del equilibrio en el cuerpo del mismo. Igualmente formula una alternativa para el cuidado de la salud, aplicando el conocimiento de enfermería desde la perspectiva cultural, teniendo como punto de partida la teoría de Madeleine Leininger.

  5. Entrevista con Geoffrey Lloyd.

    OpenAIRE

    Fernando Colina Pérez; Mauricio Jalón

    2008-01-01

    Helenista y también sinólogo de relieve internacional, Geoffrey E. R. Lloyd nació en Londres (1933), de padres galeses. Es un gran historiador de la ciencia y del pensamiento griegos. En 1940 fue evacuado de Londres con su madre. Sus estudios significativos comenzaron, tras algún rodeo, en el King’s College donde estudiaba su hermano. Éste sería, como su padre, médico, y él mismo dudó en estudiar esa profesión, que late en sus libros. Pero un profesor de clásicas como John Raven –que redactó,...

  6. Entrevista con Georges Duby.

    Directory of Open Access Journals (Sweden)

    - Consejo de Redacción

    1994-01-01

    Full Text Available Duby, heredero de dos grandes historiadores como Marc Bloch y Lucien Febvre, es uno de los más importantes medievalistas europeos. Fue, y sigue siendo, un motor de la importante reforma en la historia producida desde los sesenta. En sus primeros trabajos se acusa la recepción de las ideas económicas y geográficas de la mejor historiografía. Su riguroso estudio sobre la base material de la Edad Media, le permitirá luego irrumpir en la historia de las mentalidades, analizando, como decía Febvre, el utillaje mental (vocabulario, sintaxis, lugares comunes, cuadros lógicos, etc. del Medioevo. Así, el ejemplo de Mauss y LéviStrauss le anima a trabajar sobre el matrimonio, la sexualidad y ciertos sistemas del pensamiento: el primero, con su defensa de los hechos sociales totales, y el segundo, que buscaba las dimensiones simbólicas de lo social, le impulsan a trabajar sobre la ideología entendida no como mero reflejo de la situación material sino como «proyecto de acción sobre lo vivido». A su obra individual, atenta a los impulsos culturales más vivos, se suma su empuje decisivo en la realización de proyectos colectivos como la Historia de la vida privada o la Historia de las mujeres. Prácticamente, han sido traducidos todos sus libros al castellano, y han podido verse en España asimismo varios de sus programas televisivos (ha sido presidente de la SEPT, cadena de televisión cultural fundada en 1985. La amplitud de sus intereses intelectuales, transmitidos en su obra con un lenguaje a la vez muy claro y bellamente elaborado, se hace palpable también en este diálogo.

  7. Quantificação da ilha de calor de curitiba considerando aspectos de estabilidade atmosférica

    Directory of Open Access Journals (Sweden)

    Eduardo Krüger

    2015-12-01

    Full Text Available RESUMO A relação entre crescimento urbano e o surgimento de ilhas de calor urbanas, ou seja, diferenças climáticas entre a área urbana e as áreas rurais no entorno, é demonstrada por diversos autores e em diferentes regiões climáticas. Em Curitiba, a população saltou de aproximadamente 600.000 habitantes para um milhão e meio em três décadas. O objetivo do presente trabalho é propor uma metodologia de análise da ilha de calor urbana de Curitiba (25º25'40"S, 49º16'23"W, 934m acima do nível do mar. A cidade está localizada em região de clima subtropical de altitude; o monitoramento climático foi conduzido segundo uma série anual, entre dezembro de 2011 e fevereiro de 2013, utilizando um par de estações meteorológicas dentro e fora (perifericamente da mancha urbana de Curitiba. De modo a minimizar possíveis influências atmosféricas na análise, foi feita a classificação dos dias de medição por classes de estabilidade atmosférica segundo o método de Pasquill-Gifford-Turner (PGT, procedendo-se à análise para dias com maior estabilidade atmosférica. Como complemento à análise, adota-se um modelo de conforto desenvolvido para Curitiba a partir de uma extensa pesquisa de sensação e percepção térmicas em espaços abertos, de modo a verificar o efeito integrado das diversas variáveis climáticas em termos de percentuais de horas em frio, conforto e calor e suas variações dentro e fora da área urbana. Em Curitiba, a ilha de calor urbana pode ser benéfica durante o inverno, porém trazendo consequências em termos de excesso de calor em ambientes internos no verão.

  8. Heat transfer equipment performance diagnosis of auxiliary systems in electric power stations; Diagnostico de comportamiento de equipo de transferencia de calor de sistemas auxiliares de centrales termoelectricas

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Esparza Gutierrez, Rogelio [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1990-12-31

    In this article the methodology followed to diagnose the performance of the equipment where heat is transferred from the feed water, condensate and circulation water systems in fossil power plants (FPP). The data collection is made with the unit in normal operation, using local instrumentation without taking the equipment out of service for its installation. The equipment diagnosis is made through the analysis of the collected data in actual operation and the design data; for this purpose a thermal balance of the interested systems is performed to obtain all the conditions an operation data. Later on the performance indicative parameters (PIP) of actual operation and design are calculated and compared one against the other. Such a comparison reveals the performance deterioration and the possible equipment faults. The data obtained and the supplementary information are stored in a data base whose objective is that Comision Federal de Electricidad has on hand a prompt access to them in order to control the performance, compare them among similar units and power stations, and inclusively verify possible recurrent causes of low availability in the referred systems. [Espanol] En este articulo se presenta la metodologia seguida para diagnosticar el comportamiento de equipos en los que se transfiere calor de los sistemas de agua de alimentacion, condensado y circulacion de las centrales termoelectricas (CTE). La toma de datos se realiza con la unidad en operacion normal, utilizando instrumentacion local sin necesidad de sacar de servicio a los equipos para su instalacion, ya que se ocupan los mismos puntos para instrumentos con que cuentan por diseno. El diagnostico de los equipos se realiza mediante el analisis de los datos recopilados, tanto de operacion real como de diseno; para ello, se efectua un balance termico de los sistemas de interes para obtener todas las condiciones y los datos de operacion. Posteriormente, se calculan los parametros indicativos de

  9. preescolares desnutridos con madres con obesidad y sin obesidad

    Directory of Open Access Journals (Sweden)

    Viridiana Vanessa Conzuelo-González

    2009-01-01

    Full Text Available El primer objetivo fue conocer cuántos menores de cinco años con diferentes grados de desnutrición tienen una madre con sobrepeso/obesidad/ en una comunidad indígena que vive en extrema pobreza y bajo condiciones de migración masculina internacional. El segundo fue comparar tres variables socionutricionales (ingreso familiar, educación de la madre y adecuación nutrimental de la dieta diaria entre estos hogares y los hogares con desnutrición infantil y madres sin obesidad. Se realizó un estudio transversal (2006-2007, en la comunidad mazahua de San Francisco Tepeolulco, Municipio de Temascalcingo; que incluyó a 85 hogares integrados por preescolares con desnutrición inscritos al programa Oportunidades. Se determinó el estado nutrición de los preescolares con indicadores antropométricos y se obtuvo el IMC de las madres de estos infantes. Se aplicó una encuesta socionutricional, incluida el recordatorio de 24 horas, y complementado con la observación participante (cualitativa. Se encontró que 83% de las madres mazahuas presentaron sobrepeso u obesidad. El estado de nutrición de los preescolares con madres con obesidad presentó un porcentaje mayor de desnutrición (76%. En la variable género, se encontró que 54% de los niños con madres con obesidad tenía baja talla. Al relacionar el nivel educativo de la madre, esta variable resultó ser estadísticamente significativa (p=0.015, donde el analfabetismo está más relacionado con la desnutrición infantil que tienen madres de bajo y/o peso normal. La elevada prevalencia de hogares conformados con preescolares con desnutrición y madres con obesidad, es un síntoma más de la pobreza en zonas indígenas en México, con bajo índice de desarrollo humano.

  10. Desarrollo de una bomba de calor de absorción a gas con fluidos orgánicos e intercambiadores de placas

    OpenAIRE

    Nogués Aymamí, Miquel

    2001-01-01

    El crecimiento de la demanda eléctrica en Cataluña entre 1986 y 1999 ha sido alrededor de un 70% y se prevé para el año 2010 que dicha demanda sea un 43% superior a la actual. Incrementos similares en otras comunidades pueden provocar un colapso en el sistema eléctrico español.A pesar de que el crecimiento del consumo energético se debe principalmente al incremento de la capacidad productiva de nuestro país, cada vez es más significativo el efecto de la proliferación de equipos de climatizaci...

  11. Transferencia de masa y calor en absorbedores adiabáticos con aplicación de la disolución nitrato de litio-amoniaco

    OpenAIRE

    Zacarías Santiago, Alejandro

    2009-01-01

    El continuo cambio climático, la incertidumbre de que los combustibles fósiles pueden agotarse y el aumento de las emisiones de dióxido de carbono, han motivado a varios países a poner especial interés en la investigación de nuevas fuentes de energía y de técnicas que puedan aprovechar mejor los recursos energéticos. Entre las técnicas que apoyan el mejor aprovechamiento de los recursos energéticos, se encuentran los Sistemas de Refrigeración por Absorción, SRA, para producción de frío solar,...

  12. Residual tissue post splenectomy detected by splenic scintillography with erythrocytes damaged by heat; Tejido residual postesplenectomia detectado por centellografia esplenica con eritrocitos danados por calor

    Energy Technology Data Exchange (ETDEWEB)

    Rivera B, B.; Garcia C, E.S.; Garcia O, J.R. [Centro Medico ABC, Departamento de Medicina Nuclear, Mexico, D.F. (Mexico)

    2005-07-01

    Feminine of 26 years old with diagnostic of purple thrombocytopenic idiopathic to those 4 years of age, tried with steroids and splenectomy at 11 years old. Pathway practically asymptomatic until 4 months ago she had presented asthenia, adynamia and general uneasiness, with platelet figures of 40,000 plat/microliter. It was carried out scintillographic study with damaged erythrocytes for post surgical remainder search. Its were took two-dimensional images and tomography by single photon emission (SPECT), being knitted splenic residual in area of anatomical projection of the spleen. (Author)

  13. PREFACE: 16th International Conference on Calorimetry in High Energy Physics (CALOR 2014)

    Science.gov (United States)

    Novotny, Rainer W.

    2015-02-01

    The XVIth International Conference on Calorimetry in High Energy Physics - CALOR 2014 - was held in Giessen, Germany from 6-11 April 2014 at the Science Campus of the University. It was hosted by the Justus-Liebig-University and the HIC for FAIR Helmholtz International Center. The series of conferences on calorimetry were started in 1990 at Fermilab and are focusing primarily on operating and future calorimeter systems within the Hadron and High-Energy Physics community without neglecting the impact on other fields such as Astrophysics or Medical Imaging. Confirmed by the impressive list of over 70 oral presentations, 5 posters and over 100 attendees, the field of calorimetry appears alive and attractive. The present volume contains the written contributions of almost all presentations which can be found at http://calor2014.de. Time slots of 15 or 30 minutes including discussion were allocated. The conference was accompanied by a small exhibition of several industrial companies related to the field. The day before the opening of the scientific program, Richard Wigmans gave an excellent and vivid tutorial on basic aspects on calorimetry meant as an introduction for students and conference attendees new in the field. The opening ceremony was used to give an impression of the present and future status and the scientific program of the new FAIR facility nearby at Darmstadt presented by Klaus Peters from GSI. The conference program of the first day was dedicated to the performance and required future upgrade of the LHC experiments, dominated by ATLAS, CMS and LHCb. The program of the next day contained specific aspects on electronics and readout as well as calorimetry in outer space. Several contributions discussed in detail new concepts for hadron calorimeters within the CALICE collaboration completed by a session on sampling calorimeters. The next sections were dedicated to operating and future calorimeters at various laboratories and covering a wide range of

  14. Mild caloric restriction up-regulates the expression of prohibitin: A proteome study

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Shoko; Masuda, Junko; Shimagami, Hiroshi [Department of Applied Biological Chemistry, The University of Tokyo, Tokyo (Japan); Ohta, Yutaka; Kanda, Tomomasa [Research Laboratories for Health and Gustatory Science, Asahi Breweries Limited, Ibaraki (Japan); Saito, Kenji [Department of Applied Biological Chemistry, The University of Tokyo, Tokyo (Japan); Corporate Sponsored Research Program ' Food for Life' , The University of Tokyo, Tokyo (Japan); Kato, Hisanori, E-mail: akatoq@mail.ecc.u-tokyo.ac.jp [Department of Applied Biological Chemistry, The University of Tokyo, Tokyo (Japan); Corporate Sponsored Research Program ' Food for Life' , The University of Tokyo, Tokyo (Japan)

    2011-02-18

    Research highlights: {yields} Proteomic analysis was performed to elucidate physiological alterations induced by mild CR. {yields} The results suggest good reproducibility and possibility to grasp the important response of CR. {yields} The increase in prohibitin abundance was observed in CR groups by proteomic analysis. {yields} We hypothesize that prohibitin might be involved in the longevity induced by CR. -- Abstract: Caloric restriction (CR) is well known to expand lifespan in a variety of species and to retard many age-related diseases. The effects of relatively mild CR on the proteome profile in relation to lifespan have not yet been reported, despite the more extensive studies of the stricter CR conditions. Thus, the present study was conducted to elucidate the protein profiles in rat livers after mild CR for a relatively short time. Young growing rats were fed CR diets (10% and 30% CR) for 1 month. We performed the differential proteomic analysis of the rat livers using two-dimensional electrophoresis combined with MALDI-TOF mass spectrometry. The most remarkable protein among the differentially expressed proteins was found to be prohibitin, the abundance of which was increased by 30% CR. Prohibitin is a ubiquitously expressed protein shown to suppress cell proliferation and to be related to longevity. The increase in prohibitin was observed both in 10% and 30% CR by Western blot analysis. Furthermore, induction of AMP-activated kinase (AMPK) protein, related to the actions of prohibitin in promoting longevity, was observed. The increased prohibitin level in response to subtle CR suggests that this increase may be one of the early events leading to the expansion of lifespan in response to CR.

  15. Leaf Caloric Value from Tropical to Cold-Temperate Forests: Latitudinal Patterns and Linkage to Productivity.

    Science.gov (United States)

    Song, Guangyan; Hou, Jihua; Li, Ying; Zhang, Jiahui; He, Nianpeng

    2016-01-01

    Leaf caloric value (LCV) reflects the capacity of a leaf to fix and accumulate solar energy through photosynthesis. We systematically investigated the LCV of 745 plant species in 9 forests, representing a range of tropical to cold-temperate forests along the 4700-km North-South Transect of Eastern China. The goals were to explore the latitudinal patterns of LCV at the levels of species, plant functional group, and community and to establish the relationship between LCV and gross primary productivity (GPP). Our results showed that LCV for all species ranged from 12.85 to 22.15 KJ g-1 with an average of 18.46 KJ g-1. Plant functional groups had a significant influence on LCV, with trees > shrubs > herbs, conifers > broadleaved trees, and evergreens > deciduous trees. The different values of LCV represented the long-term evolution and adaptation of plant species to different environments. Unexpectedly, no apparent latitudinal trends of LCV at community level were observed, although LCV at the species level clearly decreased with increasing latitude. Use efficiency of LCV (CUE, gC KJ-1), defined as the ratio of GPP to total LCV at the community level, varied quadratic with latitude and was lower in the middle latitudes. Climate (temperature and precipitation) may explain 52.9% of the variation in spatial patterns of CUE, which was positively correlated with aridity. Our findings are the first large-scale report of the latitudinal patterns of LCV in forests at the species, plant functional group, and community levels and provide new insights into the relationship between LCV and ecosystem functions in forest communities.

  16. Leaf Caloric Value from Tropical to Cold-Temperate Forests: Latitudinal Patterns and Linkage to Productivity.

    Directory of Open Access Journals (Sweden)

    Guangyan Song

    Full Text Available Leaf caloric value (LCV reflects the capacity of a leaf to fix and accumulate solar energy through photosynthesis. We systematically investigated the LCV of 745 plant species in 9 forests, representing a range of tropical to cold-temperate forests along the 4700-km North-South Transect of Eastern China. The goals were to explore the latitudinal patterns of LCV at the levels of species, plant functional group, and community and to establish the relationship between LCV and gross primary productivity (GPP. Our results showed that LCV for all species ranged from 12.85 to 22.15 KJ g-1 with an average of 18.46 KJ g-1. Plant functional groups had a significant influence on LCV, with trees > shrubs > herbs, conifers > broadleaved trees, and evergreens > deciduous trees. The different values of LCV represented the long-term evolution and adaptation of plant species to different environments. Unexpectedly, no apparent latitudinal trends of LCV at community level were observed, although LCV at the species level clearly decreased with increasing latitude. Use efficiency of LCV (CUE, gC KJ-1, defined as the ratio of GPP to total LCV at the community level, varied quadratic with latitude and was lower in the middle latitudes. Climate (temperature and precipitation may explain 52.9% of the variation in spatial patterns of CUE, which was positively correlated with aridity. Our findings are the first large-scale report of the latitudinal patterns of LCV in forests at the species, plant functional group, and community levels and provide new insights into the relationship between LCV and ecosystem functions in forest communities.

  17. Magneto-caloric effect in the pseudo-binary intermetallic YPrFe{sub 17} compound

    Energy Technology Data Exchange (ETDEWEB)

    Alvarez, Pablo [Departamento de Fisica, Universidad de Oviedo, Calvo Sotelo, s/n, 33007 Oviedo (Spain); Gorria, Pedro, E-mail: pgorria@uniovi.es [Departamento de Fisica, Universidad de Oviedo, Calvo Sotelo, s/n, 33007 Oviedo (Spain); Sanchez Llamazares, Jose L. [Division de Materiales Avanzados, Instituto Potosino de Investigacion Cientifica y Tecnologica, Camino a la presa San Jose 2055, CP 78216, San Luis Potosi (Mexico); Perez, Maria J. [Departamento de Fisica, Universidad de Oviedo, Calvo Sotelo, s/n, 33007 Oviedo (Spain); Franco, Victorino [Departamento de Fisica de la Materia Condensada, ICMSE-CSIC, Universidad de Sevilla, P.O. Box 1065, 41080 Sevilla (Spain); Reiffers, Marian; Kovac, Jozef [Institute of Experimental Physics, Watsonova 47, SK-04001 Kosice (Slovakia); Puente-Orench, Ines [Institute Laue Langevin, 6 rue Jules Horowitz, 38042 Grenoble (France); Blanco, Jesus A. [Departamento de Fisica, Universidad de Oviedo, Calvo Sotelo, s/n, 33007 Oviedo (Spain)

    2011-12-15

    Highlights: Black-Right-Pointing-Pointer YPrFe{sub 17} exhibits a broad {Delta}S{sub M}(T) associated with the ferro-to-paramagnetic phase transition (T{sub C} Almost-Equal-To 290 K). Black-Right-Pointing-Pointer We obtain |{Delta}S{sub M}| Almost-Equal-To 2.3 J kg{sup -1} K{sup -1} and RCP Almost-Equal-To 100 J kg{sup -1}for a magnetic field change of 1.5 T. Black-Right-Pointing-Pointer A single master curve for {Delta}S{sub M} is found when compared with other isostructural R{sub 2}Fe{sub 17} binary alloys. - Abstract: We have synthesized the intermetallic YPrFe{sub 17} compound by arc-melting. X-ray and neutron powder diffraction show that the crystal structure is rhombohedral with R3{sup Macron }m space group (Th{sub 2}Zn{sub 17}-type). The investigated compound exhibits a broad isothermal magnetic entropy change {Delta}S{sub M}(T) associated with the ferro-to-paramagnetic phase transition (T{sub C} Almost-Equal-To 290 K). The |{Delta}S{sub M}| ( Almost-Equal-To 2.3 J kg{sup -1} K{sup -1}) and the relative cooling power ( Almost-Equal-To 100 J kg{sup -1}) have been calculated for applied magnetic field changes up to 1.5 T. A single master curve for {Delta}S{sub M} under different values of the magnetic field change can be obtained by a rescaling of the temperature axis. The results are compared and discussed in terms of the magneto-caloric effect in the isostructural R{sub 2}Fe{sub 17} (R = Y, Pr and Nd) binary intermetallic alloys.

  18. Tecnologías emergentes para la conservación de alimentos sin calor

    Directory of Open Access Journals (Sweden)

    Fernández Molina, Juan José

    2001-01-01

    Full Text Available Not available

    Se han investigado los principios básicos de tres tecnologías emergentes para pasteurizar y esterilizar alimentos sin empleo del calor Mediante numerosos estudios se ha comprobado la efectividad de los campos eléctricos pulsantes de alta intensidad (CEPAI, los pulsos de luz (PL y los campos magnéticos oscilantes (CMO en la destrucción de microorganismos y enzimas de sistemas alimentarios. En la inactivación microbiana por CEPA!, el blanco principal es la membrana celular que, al ser sometida a campos eléctricos de alta intensidad, se hace permeable formando huecos o poros cuyo tamaño se incrementa a medida que aumenta la intensidad del campo eléctrico o el tiempo de tratamiento o se reduce la resistencia iónica del medio de pulsación. Por otra parte, los PL inducen reacciones fotoquímicas y fototérmicas en los alimentos, causando la muerte de gran cantidad de microorganismos, especialmente en productos alimenticios envasados. Los CMO producen simulación o inhibición en el crecimiento y reproducción de los microorganismos, un simple pulso de intensidad de 5-10 teslas y frecuencias de 5-500 kHz es suficiente para reducir el número de microorganismos en un mínimo de 2 ciclos logarítmicos. Se ha comprobado que estas tecnologías alargan la vida de anaquel de diversos productos alimenticios y pueden ser consideradas como sustitutos parciales de los procesos convencionales de pasteurización y esterilización de alimentos por tratamientos térmicos.

  19. Leaf Caloric Value from Tropical to Cold-Temperate Forests: Latitudinal Patterns and Linkage to Productivity.

    Science.gov (United States)

    Song, Guangyan; Hou, Jihua; Li, Ying; Zhang, Jiahui; He, Nianpeng

    2016-01-01

    Leaf caloric value (LCV) reflects the capacity of a leaf to fix and accumulate solar energy through photosynthesis. We systematically investigated the LCV of 745 plant species in 9 forests, representing a range of tropical to cold-temperate forests along the 4700-km North-South Transect of Eastern China. The goals were to explore the latitudinal patterns of LCV at the levels of species, plant functional group, and community and to establish the relationship between LCV and gross primary productivity (GPP). Our results showed that LCV for all species ranged from 12.85 to 22.15 KJ g-1 with an average of 18.46 KJ g-1. Plant functional groups had a significant influence on LCV, with trees > shrubs > herbs, conifers > broadleaved trees, and evergreens > deciduous trees. The different values of LCV represented the long-term evolution and adaptation of plant species to different environments. Unexpectedly, no apparent latitudinal trends of LCV at community level were observed, although LCV at the species level clearly decreased with increasing latitude. Use efficiency of LCV (CUE, gC KJ-1), defined as the ratio of GPP to total LCV at the community level, varied quadratic with latitude and was lower in the middle latitudes. Climate (temperature and precipitation) may explain 52.9% of the variation in spatial patterns of CUE, which was positively correlated with aridity. Our findings are the first large-scale report of the latitudinal patterns of LCV in forests at the species, plant functional group, and community levels and provide new insights into the relationship between LCV and ecosystem functions in forest communities. PMID:27341474

  20. Impact of time since last caloric intake on blood glucose levels.

    Science.gov (United States)

    Moebus, Susanne; Göres, Laura; Lösch, Christian; Jöckel, Karl-Heinz

    2011-09-01

    Blood glucose (BG) is usually measured after a caloric restriction of at least 8 h; however evidence-based recommendations for the duration of a fasting status are missing. Here we analyze the effect of fasting duration on levels of BG to determine the minimal fasting duration to achieve comparable BG levels to conventional fasting measurements. We used data of a cross-sectional study on primary care patients, performed in October 2005. We included 28,024 individuals (age-range 18-99 years; 63% women) without known diabetes mellitus and without missing data for BG and fasting status. We computed general linear models, adjusting for age, sex, time of blood withdrawal, systolic blood pressure, waist circumference, total- and HDL-cholesterol, physical activity, smoking, intake of beta-blocker and alcohol. We tested the intra-individual variability with respect to fasting status. Overall, the mean BG differed only slightly between individuals fasting ≥ 8 h and those fasting fasting differences of BG diminished in men to -0.08 mmol/L (95%-CI: -0.15; -0.01 mmol/L), in women to -0.07 mmol/L (-0.12; -0.03 mmol/L) compared to individuals fasting ≥ 8 h. Noteworthy, age, time of day of blood withdrawal, physical activity, and intake of hard liquor influenced BG levels considerably. Our data challenge the necessity for a fasting duration of ≥ 8 h when measuring blood glucose, suggesting a random sampling or a fasting duration of 3 h as sufficient. Rather, our study indicates that essentially more effort on the assessment of additional external/internal factors on BG levels is necessary. PMID:21822717

  1. Thermal treatment of high-caloric waste in fluidized bed incineration plants in Austria

    International Nuclear Information System (INIS)

    The importance of thermal treatment of waste and residues in Austria is expected to rise due to the current changes of the legal situation in waste management. Assessing the rank order of different thermal treatment processes for waste management it has been shown that - especially caused by the rising importance of the mechanical treatment step in the mechanical-biological residual waste treatment and the subsequent necessity of the thermal treatment of a high-caloric preprocessed waste stream - the importance of the fluidized bed technology will increase. The main advantages are the high existing capacities as well as the flexibility of this technology in regard of fuel properties and further on the fact of the lacking influence of the ash towards the quality of a product. This is true although the thermal treatment in fluidized bed incinerators requires some processing of the waste. This doctoral thesis also contains a thorough physical and chemical characterization of various waste fuels - especially those which have been used during full scale incineration experiments. This characterization includes a comparison with fossil fuel. The practical part contains the documentation and balancing of full scale incineration experiments. A comparison of a reference experiment with experiments when waste fuel has been thermally utilized showed that a significant increase of emissions to the atmosphere has not been observed. Based on the incineration experiments conclusions in regard of waste fuels as well as different categories of thermal treatment plants are being stated. Finally, a recommendation of the assignation of various waste streams to different categories of thermal treatment plants is being made. (author)

  2. PREFACE: XVth International Conference on Calorimetry in High Energy Physics (CALOR2012)

    Science.gov (United States)

    Akchurin, Nural

    2012-12-01

    The XVth International Conference on Calorimetry in High Energy Physics, CALOR2012, was held in Santa Fe, New Mexico from 4-8 June 2012. The series of conferences on calorimetry started in 1990 at Fermilab, and they have been the premier event for calorimeter aficionados, a trend that CALOR2012 upheld. This year, several presentations focused on the status of the major calorimeter systems, especially at the LHC. Discussions on new and developing techniques in calorimetry took a full day. Excellent updates on uses of calorimeters or about ideas that are deeply rooted in particle physics calorimetry in astrophysics and neutrino physics were followed by talks on algorithms and special triggers that rely on calorimeters. Finally, discussions of promising current developments and ongoing R&D work for future calorimeters capped the conference. The field of calorimetry is alive and well, as evidenced by the more than 100 attendees and the excellent quality of over 80 presentations. You will find the written contributions in this volume. The presentations can be found at calor2012.ttu.edu. The first day of the conference was dedicated to the LHC. In two invited talks, Guillaume Unal (CERN) and Tommaso Tabarelli de Fatis (Universita' & INFN Milano Bicocca) discussed the critical role electromagnetic calorimeters play in the hunt for the Standard Model Higgs boson in ATLAS and CMS, respectively. The enhanced sensitivity for light Higgs in the two-gamma decay channel renders electromagnetic calorimeters indispensible. Much of the higher mass region was already excluded for the SM Higgs by the time of this conference, and after less than a month, on 4 July, CERN announced the discovery of a new boson at 125 GeV, a particle that seems consistent with the Higgs particle so far. Once again, without the electromagnetic calorimeters, this would not have been possible. Professor Geoffrey West from the Santa Fe Institute gave the keynote address. His talk, 'Universal Scaling Laws

  3. Refrigeración por absorción con nh3/h2o/hidróxidos

    OpenAIRE

    Steiu, Marieta Simona

    2010-01-01

    En esta tesis doctoral se estudia el uso de las mezclas ternarias NH3/H2O/XOH (X: NaOH, KOH, LiOH) en ciclos de refrigeración por absorción activados con energía solar térmica o calor residual. La adición de hidróxidos alcalinos NaOH, KOH o LiOH a la mezcla amoníaco/agua disminuye la temperatura de ebullición de la mezcla y favorece la separación del amoniaco al desplazar el equilibrio de disolución del amoniaco en agua hacia la separación del amoniaco en fase gas, con la consiguiente reducci...

  4. Current status of the second generation of parabolic trough solar concentrator for heat generation process designed at the IIE; Estado actual de la segunda generacion del concentrador solar de canal parabolico para generacion de calor de proceso disenado en el IIE

    Energy Technology Data Exchange (ETDEWEB)

    Ramos Berumen, Carlos; Ramirez Benitez, Juan Rafael; Beltran Adan, Jose [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: cramos@iie.org.mx; rramirez@iie.org.mx; jose.beltran@iie.org.mx

    2010-11-15

    The transformation industry normally uses thermal energy within its process, it obtains this energy burning fossils fuel, a new option is to use new technologies like the thermal solar technology like the parabolic trough, this is a long parabolic mirror used to reflect the sunlight and focused on an absorber tube with a heat-conducting fluid inside. The Instituto de Investigaciones Electricas (IIE) developed a prototype of parabolic trough that is operating in different industries, in this article are showing some improvements to the design, giving like result the second generation of the prototype of parabolic trough of the IIE. [Spanish] La industria de la transformacion normalmente utiliza energia termica dentro de su proceso, los medios convencionales para obtener esta energia es el quemar combustibles fosiles, una opcion que aplica nuevas tecnologias es el uso de la tecnologia termosolar a concentracion que le permitira a la industria utilizar el sol como fuente de energia primaria. El uso de esta tecnologia permitira a las empresas generar calor de proceso sin contaminar el ambiente, lo que dara como resultado empresas competitivas y autosuficientes. Para alcanzar temperaturas utiles a estas aplicaciones se requiere concentrar la energia solar en un area mas pequena, siendo la tecnologia mas extendida la de canal parabolico, el principio de operacion de esta tecnologia es la de concentrar la radiacion solar en el eje receptor preparado con una pintura especial para una mejor absorcion del calor y una cubierta de vidrio para evitar perdidas termicas, dentro del tubo circula un fluido caloportador el cual lleva el calor util hacia el proceso. El Instituto de Investigaciones Electricas (IIE) desarrollo un prototipo de canal parabolico, actualmente estan operando en diferentes industrias, resultado de estas aplicaciones se llevo a cabo una evaluacion del prototipo, se detectaron algunos puntos de mejoras al diseno, los cuales se exponen en este articulo, dando

  5. Analysis regarding steam generator furnace's incident heat, temperature and composition of combustion gases; Analisis de calor incidente, temperatura y composicion de gases de combustion en hornos de generadores de vapor

    Energy Technology Data Exchange (ETDEWEB)

    Diego Marin, Antonio [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2006-07-01

    In order to obtain more precise evaluations of the combustion process in the furnace of a steam generator a suction pyrometer has been integrated to measure the temperature of the combustion gases; an ellipsoidal radiometer to measure the incident heat by thermal radiation in the water walls; a water cooled probe to determine the particle concentration, as well as a water cooled probe to determine the composition of the combustion gases present. This document clarifies the form of use of these instruments and their engineering specifications, simultaneously presenting an analysis that considers, unlike others, the internal conditions of the furnace to obtain a more precise evaluation of the efficiency that the combustion process presents and bases for the taking of preventive actions in specific zones of the furnace. Thus, the present work exhibits instruments and techniques of analysis to study the phenomena occurring within a steam generator. [Spanish] Con el fin de obtener evaluaciones mas precisas del proceso de combustion en el horno de un generador de vapor, se ha integrado un pirometro de succion para medir la temperatura de los gases de combustion; un radiometro elipsoidal para medir el calor incidente por radiacion termica en las paredes del agua; una sonda enfriada con agua para determinar la concentracion de particulas, asi como una sonda refrigerada con agua para determinar la composicion de los gases de combustion presentes. Este documento aclara la forma de uso de estos instrumentos y sus especificaciones tecnicas, a la vez que presenta un analisis que considera, a diferencia de otros, las condiciones internas del horno para obtener una evaluacion mas precisa sobre la eficiencia del proceso de combustion y bases para la toma de acciones preventivas en zonas especificas del horno. Asi, el presente trabajo exhibe instrumentos y tecnicas de analisis para estudiar los fenomenos que ocurren dentro de un generador de vapor.

  6. Entrevista con Alberto Tenenti.

    Directory of Open Access Journals (Sweden)

    - Consejo de Redacción

    1995-01-01

    Full Text Available Gran especialista en historia moderna, Alberto Tenenti nació en Viareggio, en 1924. Tras realizar estudios superiores en Italia, trabajó en el Centre National de la Recherche Scientifique varios años, asesorado por Lucien Febvre. Ha dirigido el Archivo del Estado de Brescia; y, más tarde, ha enseñado en París, desde una cátedra en la École Pratique des Hautes Études en Sciences Sociales (VI Sección, alIado de Braudel. Su Il senso della morte e l'amore della vita nel Rinascimento, de 1957, es una obra maestra sobre los orígenes de la sensibilidad moderna: sin olvidar el naciente vitalismo, estudia el desarrollo de dos motivos, el del ars moriendi, que tiene su evolución propia desde 1350 hasta su difusión impresa, y el de lo macabro, que refleja la crisis de conciencia del siglo XV y adquiere «unas dimensiones desconocidas y verdaderamente anormales». En este libro sobre un problema clave como la muerte, apela de modo notable a la iconografía: Tenenti ha recordado que la cultura tradicional, eclesiástica sobre todo, percibió un mayor peligro en la capacidad de reflexión autónoma y de crítica de los hombres de letras, que en las renovaciones radicales de los artistas. Numerosos trabajos de conjunto realizados por él han perseguido una historia global: Los fundamentos del mundo moderno; Florencia en la época de los Medicis; La formación del mundo moderno; El Renacimiento; el primero de ellos estaba firmado con un historiador de su misma generación, R. Romano, estudioso de las relaciones comerciales en la época moderna en Europa y en la América española. Tenenti ha publicado monografías (Venezia e i corsari, 1961, colecciones de artículos (Credence, ideologie, libertinismi tra medioevo ed eta moderna, 1978; Stato: un'idea, una logica. Dal comune italiano all'assolutismo francese, 1987 y editado a clásicos como Il libri della famiglia de L. B. Alberti, 1969. Es también especialista en temas económicos, como el del

  7. Puentes con vigas pretensadas

    Directory of Open Access Journals (Sweden)

    Editorial, Equipo

    1965-07-01

    Full Text Available This paper describes one of the three bridges which Hidrocivil, S. A., has built in Catalonia (northern Spain, over the river Ripoll. The other two bridges are very similar to this one, both in construction and design, and show only minor adjustments to the local topography. The contracting firm proposed several alterations in the prefabrication and constructional procedure, in relation to the initial project, and these changes were accepted. The main feature of these projects is the use of prestressed beams, built at the workshop in sections, and joined together by means of sixty 7 mm cables in each beam. As the shear forces are more acute at the joints, the end of each section has a kind of diaphragm, to provide a large contact area, and hence greater surface to transmit the shear forces. The methods of construction are also of interest. Briefly, they involve building the bridge piles, and use these to support a provisional structure with transversal movement. This provisional structure, in turn, served as platform for two bridge cranes, which lifted the girders to their final location. After the first span was completed, the deck was concreted and the auxiliary structure pushed forward to the next span, to repeat the same operations. This arrangement saved the use of provisional framework.En este trabajo se describe uno de los tres puentes que Hidrocivil, S. A., ha construido.—previo concurso— en la región catalana; concretamente, el que salva el río Ripoll. Los otros dos no han sido objeto de descripción general por ser muy similares, en lo que a ejecución y concepción se refiere, con la única variante que presentan las características topográficas locales. La empresa propuso ciertas variantes— que fueron aceptadas— en la prefabricación y métodos de construcción. El interés de estas obras se centra en el empleo de vigas pretensadas, prefabricadas en taller por trozos, y solidarizados en el mismo mediante las operaciones

  8. Entrevista con Bernard Vincent.

    Directory of Open Access Journals (Sweden)

    Fernando Colina Pérez

    2006-01-01

    Full Text Available Nacido en París (1941, Bernard Vincent es un historiador de renombre en Europa y América del Sur. Consiguió su agregación universitaria en 1966, y desde sus inicios se centró en la Historia Moderna, particularmente en grupos marginales de la España de los siglos XVI-XVII. Ha residido en nuestro país muchos años. Vincent fue miembro de la sección científica de la Casa de Velázquez inicialmente (1968-1971, algo más tarde director de estudios (1977-1978, y a continuación secretario general (1978-1982 de dicha institución. Asimismo ha encabezado el programa de cooperación francoespañol en ciencias sociales (1993-1996. Por otra parte, ha enseñado en la Universidad de París VII, en varias etapas de su vida; pero, sobre todo, ha pertenecido siempre a centros superiores de investigación: Centre National de la Recherche Scientifique (1976-1978, y a la École des Hautes Études en Sciences Sociales, en donde ha sido director de estudios desde 1988 –era doctor de Estado ya en 1986–, y luego responsable de la Sección de Historia, desde 1996 hasta hoy. Sus colaboraciones con las universidades y centros investigadores españoles han sido constantes hasta el presente. Por añadidura, ha sido miembro del Consejo Nacional de las Universidades en Francia, en lo relativo a la historia moderna y contemporánea (1987-1988, 1992-1995, y es desde hace años miembro de la madrileña Academia de la Historia.

  9. Nutrient and caloric dynamics in Avicennia marina leaves at different developmental and decay stages in Zhangjiang River Estuary, China

    Science.gov (United States)

    Zhou, Hai-Chao; Wei, Shu-Dong; Zeng, Qi; Zhang, Li-Hua; Tam, Nora Fung-yee; Lin, Yi-Ming

    2010-03-01

    Avicennia marina is a typical mangrove species in the subtropical coastlines of China. The main objective of this study was to assess nutrient and caloric dynamics in A. marina leaves at different developmental and decay stages. Decomposition studies using litter bags suggested that the time required for the loss of half of the initial dry weight ( t50) was 19 days. The extracts of A. marina leaves contained non-tannin phenolics and tannin phenolics (hydrolysable tannin), but no condensed tannin. Non-tannin phenolics and tannin phenolics contents did not differ significantly from each other at various developmental stages, but decreased rapidly during leaf decomposition. Avicennia marina leaves had high N levels, and both N and P concentrations decreased significantly during senescence. During decomposition, N concentration of the leaf litter increased gradually but the phosphorus concentration showed a decrease in the first week, and both N and P remained the same towards the end of the experiment. The gross caloric value (GCV) of mature leaves was significantly higher than those of young and senescent leaves, while ash-free caloric value (AFCV) did not change significantly during leaf development and senescence. During leaf decomposition, both GCV and AFCV increased gradually and remained the same at late stages. In subtropical Zhangjiang River Estuary, high N levels and lack of condensed tannins in A. marina leaves were responsible for the fast rate of decay. Non-tannin phenolics and tannin phenolics had no great effect on rate of decay. Nitrogen resorption during leaf senescence, and high litter decomposition followed by nitrogen immobilization are the important nutrient conservation strategy for A. marina.

  10. Calentamiento global con Scratch y escuelas eficientes con Arduino

    OpenAIRE

    Ainzua Cemborain, José Ignacio

    2014-01-01

    Este trabajo final de máster está formado por dos proyectos con metodología de aprendizaje basado en proyectos (ABP). El primero de ellos se realiza en la asignatura de Tecnología y en coordinación con la asignatura de Ciencias Naturales, y el segundo únicamente para Tecnología. En la primera parte del proyecto se analiza la metodología ABP utilizada y se compara con la tradicional. Posteriormente se estudian las tres herramientas utilizadas en este proyecto como son; Scratch, Scratch for...

  11. Chronic Caloric Restriction and Exercise Improve Metabolic Conditions of Dietary-Induced Obese Mice in Autophagy Correlated Manner without Involving AMPK

    Directory of Open Access Journals (Sweden)

    Mingxia Cui

    2013-01-01

    Full Text Available Aim. To investigate the role of AMPK activation and autophagy in mediating the beneficial effects of exercise and caloric restriction in obesity. Methods. Dietary-induced obesity mice were made and divided into 5 groups; one additional group of normal mice serves as control. Mice in each group received different combinations of interventions including low fat diet, caloric restriction, and exercise. Then their metabolic conditions were assessed by measuring serum glucose and insulin, serum lipids, and liver function. AMPK phosphorylation and autophagy activity were detected by western blotting. Results. Obese mice models were successfully induced by high fat diet. Caloric restriction consistently improved the metabolic conditions of the obese mice, and the effects are more prominent than the mice that received only exercise. Also, caloric restriction, exercise, and low fat diet showed a synergistic effect in the improvement of metabolic conditions. Western blotting results showed that this improvement was not related with the activation of AMPK in liver, skeletal muscle, or heart but correlates well with the autophagy activity. Conclusion. Caloric restriction has more prominent beneficial effects than exercise in dietary-induced obese mice. These effects are correlated with the autophagy activity and may be independent of AMPK activation.

  12. Auditory Function in Rhesus Monkeys: Effects of Aging and Caloric Restriction in the Wisconsin Monkeys Five Years Later

    OpenAIRE

    Fowler, Cynthia G.; Chiasson, Kirstin Beach; Leslie, Tami Hanson; Thomas, Denise; Beasley, T. Mark; Kemnitz, Joseph W; Weindruch, Richard

    2010-01-01

    Caloric restriction (CR) slows aging in many species and protects some animals from age-related hearing loss (ARHL), but the effect on humans is not yet known. Because rhesus monkeys are long-lived primates that are phylogenically closer to humans than other research animals are, they provide a better model for studying the effects of CR in aging and ARHL. Subjects were from the pool of 55 rhesus monkeys aged 15–28 years who had been in the Wisconsin study on CR and aging for 8–13.5 years. Di...

  13. Effects of Caloric Intake on Intestinal Mucosal Morphology and Immune Cells in Rats Treated with 5-Fluorouracil

    OpenAIRE

    Murakami, Mariko; Sato, Norifumi; Tashiro, Katsufumi; Nakamura, Tsuyoshi; Masunaga, Hiroaki

    2009-01-01

    Anticancer drugs have been reported to damage the intestinal mucosa. We evaluated the effects of caloric intake on the mucosal morphology and immune cells in rats treated with 5-fluorouracil (5-FU). Rats were received a liquid diet plus 5-FU treatment for 8 days as follows: Low calorie group (25 kcal/day with 5-FU), Normal calorie group (50 kcal/day with 5-FU), and Control group (50 kcal/day with saline). The mucosal morphology, cell numbers and phenotypes of spleen and intraepithelial lympho...

  14. Effects of immobilisation and caloric restriction on antioxidant parameters and T-cell apoptosis in healthy young men

    Science.gov (United States)

    Ellinger, S.; Arendt, B. M.; Boese, A.; Juschus, M.; Schaefer, S.; Stoffel-Wagner, B.; Goerlich, R.

    Background: Astronauts are exposed to oxidative stress due to radiation and microgravity, which might impair immune functions. Effects of hypocaloric nutrition as often observed in astronauts on oxidative stress and immune functions are not clear. We investigated, if microgravity, simulated by 6 Head-down tilt (HDT) and caloric restriction (-25%, fat reduced) with adequate supply of micronutrients affect DNA-damage in peripheral leukocytes, antioxidant parameters in plasma, and T-cell apoptosis. Material & Methods: 10 healthy male non-smokers were subjected to 4 different interventions (normocaloric diet or caloric restriction (CR) in upright position (UP) or HDT) for 14 days each (cross-over). DNA-damage in peripheral leukocytes (Comet Assay), trolox equivalent antioxidant capacity (TEAC) and uric acid in plasma were measured before, after 5, 10, and 13 days of intervention, and after 2 days recovery. T-cell apoptosis (Annexin V binding test) was assessed before and after intervention. Results: Preliminary results show that only endogenous, but not ex vivo H2O2-induced DNA strand breaks were reduced by CR compared to normocaloric diet. In upright position, endogenous DNA strand breaks decreased continuously during CR, reaching significance after recovery. During HDT, caloric restriction seems to counteract a temporary increase in DNA strand breaks observed in subjects receiving normocaloric diet. TEAC was reduced during HDT compared to UP in subjects under caloric restriction. An increase in plasma uric acid related to intervention occurred only after 5 days HDT in CR vs. normocaloric diet. T-cell apoptosis was not affected by any kind of intervention. Conclusion: Neither HDT nor CR with sufficient supply of micronutrients seem to induce oxidative stress or T-cell apoptosis in healthy young men. In contrast, CR might prevent endogenous DNA-damage in peripheral leukocytes. As DNA-damage is a risk factor for carcinogenesis, protective effects of energy reduction are

  15. Distúrbios causados pelo frio e pelo calor durante corridas de longa distância

    Directory of Open Access Journals (Sweden)

    1999-06-01

    Full Text Available Muitos corredores amadores e de elite participam todos os anos de corridas de longa distância. Quando estes eventos ocorrem em temperaturas altas ou baixas, aumenta o risco de distúrbios térmicos. Contudo, a hipertermia induzida pelo exercício, a hipotermia, a desidratação e outros problemas relacionados podem ser minimizados através de esclarecimentos e um preparo antes do evento. Este documento fornece recomendações para o diretor médico e outras autoridades da organização das corridas nas seguintes áreas: planejamento, profissionais envolvidos na organização, instalações, suprimentos, equipamento e comunicação; fornecimento de esclarecimentos aos participantes; avaliação do estresse térmico; fornecimento de líquidos; e prevenção de questões legais em potencial. Este posicionamento oficial também descreve as condições predisponentes, as formas de diagnóstico e o tratamento dos quatro distúrbios ambientais mais comuns: exaustão pelo calor, colapso pelo calor, hipotermia e congelamento de extremidades. Os objetivos deste documento são: 1 Educar os organizadores e os participantes de corridas de longa distância a respeito das formas mais comuns de distúrbios térmicos incluindo as condições predisponentes, sinais de alerta, suscetibilidade e a redução de sua incidência; 2 Alertar os organizadores sobre as suas responsabilidades civis em potencial no que concerne à segurança do evento e à prevenção de lesões; 3 Recomendar que os organizadores consultem arquivos locais de meteorologia e planejem eventos em horas que provavelmente causem menos estresse térmico de modo a minimizar os efeitos deletérios sobre os participantes; 4 Estimular os organizadores a alertar os participantes sobre o estresse térmico no dia da corrida e as suas implicações no que tange aos distúrbios causados pelo frio e pelo calor; 5 Informar os organizadores sobre as ações preventivas que podem reduzir a incidência dos

  16. Recuperación de calor de aire de ventilación en clima frío

    OpenAIRE

    Vakazova, Lilia

    2014-01-01

    El clima es factor determinante en las decisiones tomadas en proyecto de un edificio. Actualmente el ahorro de energía es un tema que cada dia adquiere mas importancia y valor. En los climas frios la demanda de energia depende mucho de demanda en calefacción y el factor cuya influencia es muy alta es ventilación. Las perdidas por ventilación pueden llegar a un porcentaje muy importante, por lo cual para reducir las perdidas se aprovecha el calor de aire de ventilación. En clima fria para v...

  17. Effects of adiposity and 30 days of caloric restriction upon protein metabolism in moderately versus severely obese women

    OpenAIRE

    Henderson, G. C.; Nadeau, D; Horton, E.S.; Nair, K. S.

    2010-01-01

    Protein metabolism adapts during caloric restriction (CR) to minimize protein loss, and it is unclear if greater fat stores favorably affect this response. We sought to determine if protein metabolism is related to degree of obesity and if the response to CR is impacted by pre-CR adiposity level. Whole body protein metabolism was studied in 12 obese women over a wide range of body mass index (BMI) (30-53kg/m2) as inpatients using [1-13C]leucine as a tracer following 5 days of a weight maintai...

  18. Transformaciones Microestructurales en Soldaduras Disímiles de Acero Inoxidable Austenítico con Acero Inoxidable Ferrítico

    Directory of Open Access Journals (Sweden)

    Sara María Aguilar-Sierra

    2015-03-01

    Full Text Available En este trabajo se estudian los fenómenos metalúrgicos que ocurren en la soldadura SMAW de un acero inoxidable ferrítico AISI 430 con un acero inoxidable austenítico AISI 316L. Para el estudio se utilizaron dos tipos de electrodos: austenítico AWS E309L y dúplex AWS E2209-16, ambos con un diámetro de 3,2 mm. Las uniones soldadas se realizaron con un solo pase y se variaron simultáneamente la corriente y la velocidad de soldadura; las condiciones fueron 49 A y 2,4 mm.s–1como valores bajos y 107 A y 4,3 mm.s–1como valores altos. Se evaluó la influencia del tipo de electrodo y de los parámetros de soldadura en la evolución microestructural de las zonas afectadas por el calor y de las zonas de fusión, encontrando diferencias en la morfología y cantidad de ferrita delta para todas las condiciones estudiadas. Se evidenció crecimiento y refinación de grano ferrítico y formación de martensita en la zona afectada por el calor del metal base ferrítico. Se evaluó también la resistencia a la tensión hallando similitudes en todas las soldaduras.

  19. Insights Into The Beneficial Effect Of Caloric/ Dietary Restriction For A Healthy And Prolonged Life

    Directory of Open Access Journals (Sweden)

    Rani ePallavi

    2012-08-01

    Full Text Available Over the last several years, new evidence has kept pouring in about the remarkable effect of caloric restriction (CR on the conspicuous bedfellows- aging and cancer. Through the use of various animal models, it is now well established that by reducing calorie intake one can not only increase life span but, also, lower the risk of various age related diseases such as cancer. Cancer cells are believed to be more dependent on glycolysis for their energy requirements than normal cells and, therefore, can be easily targeted by alteration in the energy-metabolic pathways, a hallmark of CR. Apart from inhibiting the growth of transplantable tumors, CR has been also shown to inhibit the development of spontaneous, radiation and chemically induced tumors. The question regarding the potentiality of the anti-tumor effect of CR in humans has been in part answered by the resistance of a cohort of women, who had suffered from anorexia in their early life, to breast cancer. However, human research on the beneficial effect of CR is still at an early stage and needs further validation. Though the complete mechanism of the anti-tumor effect of CR is far from clear, the plausible involvement of nutrient sensing pathways or IGF-1 pathways proposed for its anti-aging action cannot be overruled. In fact, cancer cell lines, mutant for proteins involved in IGF-1 pathways, failed to respond to CR. In addition, CR decreases the levels of many growth factors, anabolic hormones, inflammatory cytokines and oxidative markers that are deregulated in several cancers.In this review, we discuss the anti-tumor effect of CR, describing experiments done in vitro in tumor models and in vivo in mouse models in which the tumor was induced by means of radiation or chemical exposure, expressing oncogenes or deleting tumor suppression genes. We also discuss the proposed mechanisms of CR anti-tumor action. Lastly, we argue the necessity of gene expression studies in cancerous versus

  20. con el aborto provocado

    Directory of Open Access Journals (Sweden)

    José Luis Redondo Calderón

    2008-01-01

    Full Text Available Las vacunas de células diploides humanas (WI-38, MRC-5 tienen un origen éticamente objetable, dado que dichas células proceden de abortos provocados. Entre ellas destacan vacunas empleadas contra rubéola, sarampión, parotiditis, rabia, poliomielitis, viruela, hepatitis A, varicela y herpes zóster. Actualmente se encuentran en desarrollo otras vacunas cultivadas en células (293, PER.C6 transformadas mediante virus, procedentes de abortos. Entre ellas hay vacunas contra la gripe, virus respiratorio sincitial, parainfl uenza, HIV, virus del Nilo Occidental, virus Ébola, Marburg y Lassa, hepatitis B y C, glosopeda, encefalitis japonesa, dengue, tuberculosis, carbunco, peste, tétanos y paludismo. También con igual origen se trabaja en la elaboración de anticuerpos monoclonales y otras proteínas, terapia génica y genómica. Existe la tecnología necesaria para producir todo lo descrito sin recurrir a abortos provocados. Debe indicarse en los prospectos de vacunas y otros productos el origen de las células empleadas. Debe facilitarse el acceso a las vacunas existentes no cultivadas en células procedentes de abortos provocados. Debe potenciarse la investigación de opciones en aquellos casos en los que no exista una vacuna no originada en células procedentes de abortos provocados. Debe potenciarse la elaboración de anticuerpos monoclonales y de otras proteínas, así como la terapia génica y la genómica sin recurrir a células procedentes de abortos provocados. No sería consecuente rechazar productos obtenidos a partir de células troncales embrionarias y aceptar los originados en células procedentes de abortos provocados. Se debe evitar que la biotecnología basada en el aborto provocado invada todos los terrenos de la medicina.

  1. Estudio del proceso de absorción con amoniaco-agua en intercambiadores de placas para equipos de refrigeración por absorción.

    OpenAIRE

    Cerezo Román, Jesús

    2006-01-01

    En los últimos años ha aumentado la demanda de equipos de refrigeración por absorción de pequeña potencia con accionamiento térmico a baja temperatura. El desarrollo de estos equipos requiere altas prestaciones en los procesos de transferencia de calor y de materia en los componentes más críticos: absorbedor, generador y rectificador. Este trabajo forma parte del proyecto de investigación "Desarrollo de componentes avanzados para el diseño y fabricación de máquinas de refrigeración por absorc...

  2. Menú de textura modificada y su utilidad en pacientes con situaciones de riesgo nutricional

    Directory of Open Access Journals (Sweden)

    Daniel A. de Luis

    2014-04-01

    Full Text Available En el tratamiento nutricional de los pacientes con disfagia y/o ancianos debemos realizar un abordaje multidisciplinar, y una herramienta de trabajo es la modificación de la textura de los alimentos. Los pacientes con disfagia y con necesidades de una dieta modificada de textura, en general no tienen unos requerimientos de calorías y nutrientes diferentes de los que presentan las personas de su misma edad y sexo, salvo que coexista alguna condición o enfermedad. En todos ellos se debe individualizar su textura en función del paciente y del momento evolutivo de su enfermedad. El uso de dietas modificadas de textura sin individualizar, conlleva una clara disminución de la ingesta calórica y proteica, así como potenciales alteraciones nutricionales. Estos pacientes por sus características pueden tener otras patologías asociadas que obligarían a realizar modificaciones especiales, como es el caso de la diabetes mellitus, hipertensión arterial, osteoporosis y estreñimiento. En ocasiones es necesario utilizar diferentes productos artificiales para alcanzar las texturas deseadas, así como platos ya precocinados.

  3. Impactos de las islas térmicas o islas de calor urbano, en el ambiente y la salud humana. Análisis estacional comparativo: Caracas, octubre - 2009, marzo - 2010

    Directory of Open Access Journals (Sweden)

    Karenia Córdova Sáez

    2011-01-01

    Full Text Available En el primer trimestre del año 2010, la ciudad de Caracas experimentó una intensificación en la temporada de sequía con elevación de las temperaturas ambientales, alta incidencias de incendios forestales, fenómenos de calima y smog intensificados por los incendios de vegetación. Mediante el uso de geotecnologias, en particular utilizando la banda térmica del sensor LANDSAT 7 ETM +, es posible observar las variaciones en los patrones de la temperatura superficial urbana, y determinar la intensidad y extensión de las anomalías térmicas, que podrían estar relacionadas con el aumento de las temperaturas en la ciudad y la incidencia de incendios forestales. Se seleccionaron dos imágenes para octubre-2009, correspondiente al período húmedo y marzo del 2010, correspondiente a finales del período seco. Las imágenes LANDSAT-7 ETM+ analizadas, mostraron importantes diferencias en la temperatura superficial registrada en el área urbana y la zona periurbana, entre las imágenes del período húmedo (octubre-2009 y las del período seco (marzo-2010, registrándose una anomalía positiva de +10°C en marzo de2010 respecto a octubre de 2009. Los sectores con temperaturas superficiales entre 24 -27°C predominantes en la ciudad durante el período húmedo, pasan a rangos entre 28-31 °C durante el evento de calor de marzo de 2010. Del mismo modo los sectores del oeste y sur oeste de la ciudad con rangos de temperatura entre 28-31 °C y algunas áreas del sur-este, registran un incremento entre 32 a 34°C. Focos de alta temperatura asociados a incendios forestales (42-45°C ó más se observan con mayor frecuencia en las regiones peri-urbanas que bordean los sectores de bajos ingresos en el oeste y sur-oeste de la ciudad, en tanto que en la imagen de octubre de 2009, las zonas periurbanas registran rangos de temperatura entre 21-23 °C

  4. Effect of Resveratrol as Caloric Restriction Mimetic and Environmental Enrichment on Neurobehavioural Responses in Young Healthy Mice

    Directory of Open Access Journals (Sweden)

    Mustapha Shehu Muhammad

    2014-01-01

    Full Text Available Caloric restriction and environmental enrichment have been separately reported to possess health benefits such as improvement in motor and cognitive functions. Resveratrol, a natural polyphenolic compound, has been reported to be caloric restriction mimetic. This study therefore aims to investigate the potential benefit of the combination of resveratrol as CR and EE on learning and memory, motor coordination, and motor endurance in young healthy mice. Fifty mice of both sexes were randomly divided into five groups of 10 animals each: group I animals received carboxymethylcellulose (CMC orally per kg/day (control, group II animals were maintained on every other day feeding, group III animals received resveratrol 50 mg/kg, suspended in 10 g/L of (CMC orally per kg/day, group IV animals received CMC and were kept in an enriched environment, and group V animals received resveratrol 50 mg/kg and were kept in EE. The treatment lasted for four weeks. On days 26, 27, and 28 of the study period, the animals were subjected to neurobehavioural evaluation. The results obtained showed that there was no significant change (P>0.05 in neurobehavioural responses in all the groups when compared to the control which indicates that 50 mg/kg of resveratrol administration and EE have no significant effects on neurobehavioural responses in young healthy mice over a period of four weeks.

  5. Caloric Vestibular Stimulation Reduces Pain and Somatoparaphrenia in a Severe Chronic Central Post-Stroke Pain Patient: A Case Study.

    Directory of Open Access Journals (Sweden)

    Grazia Fernanda Spitoni

    Full Text Available Central post-stroke pain is a neuropathic syndrome characterized by intolerable contralesional pain and, in rare cases, somatic delusions. To date, there is limited evidence for the effective treatments of this disease. Here we used caloric vestibular stimulation to reduce pain and somatoparaphrenia in a 57-year-old woman suffering from central post-stroke pain. Resting-state functional magnetic resonance imaging was used to assess the neurological effects of this treatment. Following vestibular stimulation we observed impressive improvements in motor skills, pain, and somatic delusions. In the functional connectivity study before the vestibular stimulation, we observed differences in the patient's left thalamus functional connectivity, with respect to the thalamus connectivity of a control group (N = 20, in the bilateral cingulate cortex and left insula. After the caloric stimulation, the left thalamus functional connectivity with these regions, which are known to be involved in the cortical response to pain, disappeared as in the control group. The beneficial use of vestibular stimulation in the reduction of pain and somatic delusion in a CPSP patient is now documented by behavioral and imaging data. This evidence can be applied to theoretical models of pain and body delusions.

  6. Searching the conditions for a table-like shape of the magnetic entropy in magneto-caloric materials

    Energy Technology Data Exchange (ETDEWEB)

    Álvarez, Pablo, E-mail: pablo.alvarez@ehu.es [Departamento de Electricidad y Electrónica, Universidad del País Vasco (UPV/EHU), 48940 Leioa (Spain); Departamento de Física, Universidad de Oviedo, c/ Calvo Sotelo, s/n, 33007 Oviedo (Spain); Gorria, Pedro, E-mail: pgorria@uniovi.es [Departamento de Física, Universidad de Oviedo, c/ Calvo Sotelo, s/n, 33007 Oviedo (Spain); Sánchez Llamazares, José L. [División de Materiales Avanzados, Instituto Potosino de Investigación Científica y Tecnológica, Camino a la presa San José 2055, CP 78216 San Luis Potosí (Mexico); Blanco, Jesús A. [Departamento de Física, Universidad de Oviedo, c/ Calvo Sotelo, s/n, 33007 Oviedo (Spain)

    2013-08-15

    Highlights: •The magnetic entropy change for two-ribbon (amorphous) composite materials is investigated. •The conditions to obtain a table-like shape of the magnetic entropy change are specified. •We give the essential ingredients to maximize the effective refrigerant capacity and the efficiency. •Our findings could be used in other magneto-caloric materials to tune the temperature range for the table-like behavior. -- Abstract: We show a systematic study of the magneto-caloric response carried out on a series of FeZrB(Cu) amorphous ribbons with different Curie temperature values in the 210–320 K interval. The main aim of the work is to investigate the conditions to obtain, from the isothermal magnetic entropy change vs. temperature curves, ΔS{sub M}(T), a table-like behavior of the entropy using two-ribbon composites. Even though the maximum value of ΔS{sub M} for the composite is lower than those of the single components, the existence of a table-like behavior maximizes the effective refrigerant capacity, reaching values around 80 J/kg for an applied magnetic field change of 2 T. Furthermore, we discuss how the temperature range for such a table-like behavior can be tuned and the refrigerant capacity enhanced in terms of energy efficiency.

  7. High-Caloric and Chocolate Stimuli Processing in Healthy Humans: An Integration of Functional Imaging and Electrophysiological Findings

    Directory of Open Access Journals (Sweden)

    Deyar Asmaro

    2014-01-01

    Full Text Available There has been a great deal of interest in understanding how the human brain processes appetitive food cues, and knowing how such cues elicit craving responses is particularly relevant when current eating behavior trends within Westernized societies are considered. One substance that holds a special place with regard to food preference is chocolate, and studies that used functional magnetic resonance imaging (fMRI and event-related potentials (ERPs have identified neural regions and electrical signatures that are elicited by chocolate cue presentations. This review will examine fMRI and ERP findings from studies that used high-caloric food and chocolate cues as stimuli, with a focus on responses observed in samples of healthy participants, as opposed to those with eating-related pathology. The utility of using high-caloric and chocolate stimuli as a means of understanding the human reward system will also be highlighted, as these findings may be particularly important for understanding processes related to pathological overeating and addiction to illicit substances. Finally, research from our own lab that focused on chocolate stimulus processing in chocolate cravers and non-cravers will be discussed, as the approach used may help bridge fMRI and ERP findings so that a more complete understanding of appetitive stimulus processing in the temporal and spatial domains may be established.

  8. Diseño y Acondicionamiento de un Condensador-Separador en Sistema de Destilación de Ácidos Grasos Design and Improvement of a Condenser-Separator in a Fatty Acid Distillation System

    Directory of Open Access Journals (Sweden)

    D. Moreno-Juárez

    2005-01-01

    Full Text Available En este trabajo se presenta una solución al problema de una torre de destilación de ácidos grasos en donde las pérdidas de grasa son considerables, por arrastres hacia el sistema de vacío y por arrastres de ligeros con el destilado. Además, las emisiones contaminantes y la inestabilidad al color de los productos, hacen necesaria una re-destilación. Para esto se diseña un condensador-separador el cual se incorpora a la torre para asegurar la separación de los componentes ligeros. Se introducen una serie de cambios de diseño y operación para mejorar la eficiencia del proceso y la calidad del destilado. El condensador-separador diseñado permite reducir las pérdidas de grasa en efluentes y disminuye el costo del tratamiento del agua de enfriamiento.This study presents a solution of some problems occurring in a fatty acid distillation column in which considerable losses of fatty acids occur by suction into the vacuum system as well as losses of light fatty acids in the distillation step. Also, the polluting emissions and the color instability of the products require that they be re-distilled. For this, a condenser-separator which was installed in the column to assure separation of the lighter fractions was designed. A series of changes in the design and operation for improving the efficiency of the process and the quality of the distillate were introduced. The condenser-separator designed allowed reducing the losses of fat in effluents and lowered the cost of treating the cooling water.

  9. Evolución microestructural y comportamiento mecánico de aceros fundidos resistentes al calor sometidos a alta temperatura de servicio

    Directory of Open Access Journals (Sweden)

    Garin, J. L.

    2008-08-01

    Full Text Available The microstructure and mechanical properties evolution were determined in two cast heat-resistant steels upon annealing processes to induce sigma-phase formation. The research analyzed the influence of heating time at 1053 K on the formation of sigma and its relationship with selected mechanical properties, in HC-type steels (28,6Cr- 1,9Ni-0,4C and HD-type steels (28,3Cr-5,8 Ni-0,4. The obtained results evidenced formation of sigma-phase initially along ferrite-austenite grain boundaries, but at longer times sigma precipitates in the bulk of the ferrite grains, reaching maximum values of approximately 25 % and 55 % in HC and HD respectively, after 120 hours treatment. Precipitation of sigma in both alloys resembled the Johnson-Mehl-Avrami’s mechanism stated for nucleation and growth. The mechanical behavior mainly depicted a strong decrease of toughness and a moderated increase of hardness.

    Se determinaron los cambios producidos en la microestructura y en las propiedades mecánicas de dos aceros fundidos resistentes al calor, al ser sometidos a recocidos para inducir la formación de la fase sigma. La investigación analizó la influencia del tiempo de calentamiento a 1.053 K, en la formación de la fase sigma y su consecuente relación con algunas propiedades mecánicas seleccionadas, de aceros tipo HC (28,6Cr-1,9Ni-0,4C y HD (28,3Cr-5,8 Ni-0,4C. Los resultados obtenidos evidenciaron la formación de fase sigma, inicialmente, en los bordes de grano austenita-ferrita avanzando, luego, masivamente hacia el seno de la matriz ferrítica, para alcanzar valores extremos de aproximadamente 25 % y 55 % en HC y HD, respectivamente, al cabo de 120 h de tratamiento. La precipitación de sigma en ambos materiales exhibió un mecanismo de nucleación y crecimiento del tipo Jonson-Mehl-Avrami. El comportamiento mecánico se caracterizó, principalmente, por una drástica disminución en la tenacidad y un aumento de la dureza.

  10. Desempenho energético de bombas de calor e sistemas solares térmicos considerando perfis de extração normalizados

    OpenAIRE

    David, João Pedro Gonçalves

    2014-01-01

    Tese de mestrado em Engenharia da Energia e do Ambiente, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2014 Este trabalho tem como objetivo comparar o desempenho de sistemas solares térmicos e de bombas de calor para preparação de água quente sanitária, considerando os mesmos perfis de extração. Para o estudo dos sistemas solares efetuaram-se simulações numéricas em ambiente TRNSYS, enquanto para a análise da bomba de calor foi utilizado o método BIN modificado, p...

  11. Systematization of the environmental conditioning project in buildings with a view to optimizing the architectural projects with ragard to environmental control and energy saving. Volume 3. Sistematizacion del proyecto de acondicionamiento ambiental en la edificacion con vistas a la optimizacion de los proyectos arquitectonicos en aspectos de control ambiental y ahorro energetico

    Energy Technology Data Exchange (ETDEWEB)

    Klainsek, J.C.

    1988-07-01

    Due to its significance, energy analysis should be taken into account in both developing and optimization of hygrothermic conditioning system and new building designs. It is also necessary to determine the actual costs of energy saving and conservation modifications for existing buildings. This analysis involves a large number of repetitive calculations, so a computer application has become a necessity and a computer program has been developed to simulate energy needs for a real life office and their functions in one climate region. This program predicts heating and cooling energy requirements. The purpose of the present study is to determine the affect of envelope parameters: orientation, external walls, glazing, shadings, glass-to-wall ratio, surface absorbance of external wells (color), roofs, upon energy saving and conservation for a typical office building in Madrid.

  12. Systematization of the environmental conditioning project in buildings with a view to optimizing the architectural projects with regard to environmental control and energy saving. Sistematizacion del proyecto de acondicionamiento ambiental en la edificacion con vistas a la optimizacion de los proyectos arquitectonicos en aspectos de control ambiental y ahorro energetico

    Energy Technology Data Exchange (ETDEWEB)

    Klainsek, J.C.

    1988-07-01

    Due to its significance, energy analysis should be taken into account in both developing and optimization of hygrothermic conditioning system and new building designs. It is also necessary to determine the actual costs of energy saving and conservation modifications for existing buildings. This analysis involves a large number of repetitive calculations, so a computer application has become a necessity and a computer program has been developed to simulate energy needs for a real life office and their functions in one climate region. This program predicts heating and cooling energy requirements. The purpose of the present study is to determine the effect of envelope parameters: orientation, external walls, glazing, shadings, glass-to-wall ratio, surface absorbance of external walls (color), roofs, upon energy saving and conservation for a typical office building in Madrid.

  13. Systematization of the environmental conditioning project in buildings with a view to optimizing the architectural projects with regard to environmental control and energy saving. Volume 1. Sistematizacion del proyecto de acondicionamiento ambiental en la edificacion con vistas a la optimizacion de los proyectos arquitectonicos en aspectos de control ambiental y ahorro energetico

    Energy Technology Data Exchange (ETDEWEB)

    Klainsek, J.C.

    1988-07-01

    Due to its significance, energy analysis should be taken into account in both developing and optimization of hygrothermic conditioning system and new building designs. It is also necessary to determine the actual costs of energy saving and conservation modifications for existing buildings. This analysis involves a large number of repetitive calculations, so a computer application has become a necessity and a computer program has been developed to simulate energy needs for a real life office and their functions in one climate region. This program predicts heating and cooling energy requirements. The purpose of the present study is to determine the affect of envelope parameters: orientation, external walls, glazing, shadings, glass-to-wall ratio, surface absorbance of external well (color), roofs, upon energy saving and conservation for a typical office building in Madrid.

  14. Control system pre-feedbacked for the super heated steam temperature in heat recovering units; Sistema de control pre-retroalimentado para la temperatura de vapor sobrecalentado en recuperadores de calor

    Energy Technology Data Exchange (ETDEWEB)

    Lopez Alvarez, Hilario; Madrigal Espinosa, Guadalupe [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1996-12-31

    The study that is presented corresponds to the analysis, design and development of a pre-feedbacked control system for the superheated steam temperature regulation in the heat recovery units of a combined cycle thermoelectric power plant. The designs of the feedback controller and the pre-feedback control system were implemented based in a linear model of the tempering zone. This linear model was obtained through the application of parametric identification techniques to the non-linear mathematical model of a combined cycle power plant. [Espanol] El estudio que se presenta corresponde al analisis, diseno y desarrollo de un sistema de control pre-retroalimentado para regular la temperatura de vapor sobrecalentado en los recuperadores de calor de una central termoelectrica de ciclo combinado. Los disenos del controlador retroalimentado y del sistema de control prealimentado se realizaron con base en un modelo lineal de la zona de atemperacion. Este modelo lineal se obtuvo aplicando tecnicas de identificacion parametrica al modelo matematico no-lineal de una central de ciclo combinado.

  15. PREFACE: XVth International Conference on Calorimetry in High Energy Physics (CALOR2012)

    Science.gov (United States)

    Akchurin, Nural

    2012-12-01

    The XVth International Conference on Calorimetry in High Energy Physics, CALOR2012, was held in Santa Fe, New Mexico from 4-8 June 2012. The series of conferences on calorimetry started in 1990 at Fermilab, and they have been the premier event for calorimeter aficionados, a trend that CALOR2012 upheld. This year, several presentations focused on the status of the major calorimeter systems, especially at the LHC. Discussions on new and developing techniques in calorimetry took a full day. Excellent updates on uses of calorimeters or about ideas that are deeply rooted in particle physics calorimetry in astrophysics and neutrino physics were followed by talks on algorithms and special triggers that rely on calorimeters. Finally, discussions of promising current developments and ongoing R&D work for future calorimeters capped the conference. The field of calorimetry is alive and well, as evidenced by the more than 100 attendees and the excellent quality of over 80 presentations. You will find the written contributions in this volume. The presentations can be found at calor2012.ttu.edu. The first day of the conference was dedicated to the LHC. In two invited talks, Guillaume Unal (CERN) and Tommaso Tabarelli de Fatis (Universita' & INFN Milano Bicocca) discussed the critical role electromagnetic calorimeters play in the hunt for the Standard Model Higgs boson in ATLAS and CMS, respectively. The enhanced sensitivity for light Higgs in the two-gamma decay channel renders electromagnetic calorimeters indispensible. Much of the higher mass region was already excluded for the SM Higgs by the time of this conference, and after less than a month, on 4 July, CERN announced the discovery of a new boson at 125 GeV, a particle that seems consistent with the Higgs particle so far. Once again, without the electromagnetic calorimeters, this would not have been possible. Professor Geoffrey West from the Santa Fe Institute gave the keynote address. His talk, 'Universal Scaling Laws

  16. Long-term Effects of High and Low Glycemic Load Diets at Different Levels of Caloric Restriction on Dietary Adherence, Body Composition and Metabolism in CALERIE, a One Year Randomized Controlled Trial

    Science.gov (United States)

    Context The effects of dietary macronutrient composition and level of energy intake on adherence to a calorically-restricted diet remain uncertain. Objective To examine the effects of dietary macronutrients, and level of caloric restriction (CR), for 12 months, on adherence to the prescribed regim...

  17. con mala calidad de vida

    Directory of Open Access Journals (Sweden)

    Agustín Martín-Rodríguez

    2007-01-01

    Full Text Available En este estudio ex post facto se ha analizado si los familiares de pacientes con mala calidad de vida presentan diferencias en las variables clínicas de personalidad y relaciones familiares en función de que el paciente haya estado o no ingresado en una Unidad de Cuidados Intensivos. Seleccionamos dos grupos: 29 familiares de pacientes traumatizados graves transcurridos cuatro años de su ingreso en una UCI de Traumatología y con mala calidad de vida (debido a secuelas físicas y/o psicológicas tras el ingreso, tales como traumatismos craneoencefálicos, politraumatismos y tetraplejias traumáticas y 32 familiares de pacientes con mala calidad de vida con cuatro años de evolución de su enfermedad física (hipertensión, diabetes, artritis reumatoide y síndrome de intestino irritable que no han estado ingresados en la UCI. Para alcanzar nuestro objetivo empleamos una Encuesta Psicosocial y los siguientes instrumentos: Cuestionario de Análisis Clínico, Escala de Clima Social en la Familia y Escala de Adaptación Psicosocial de la Enfermedad. Los resultados mostraron que los familiares de pacientes con mala calidad de vida que estuvieron ingresados en la UCI hace cuatro años, presentan diferencias significativas en las variables agitación y expresividad comparados con los familiares de pacientes con mala calidad de vida que no han estado ingresados en la UCI.

  18. Encuentro con el tiempo: Adagio con variaciones de Alfredo Aracil

    Directory of Open Access Journals (Sweden)

    Rosa María Rodríguez Hernández

    2012-01-01

    Full Text Available Examinando analíticamente la obra sinfónica Adagio con variaciones de Aracil, estudiaremos los principales componentes para concluir con una evaluación de los mismos. A través de la cronología de la obra de Aracil175, observamos la importancia que adquiere en su trayectoria la memoria; su pensamiento va siempre unido a ésta. Uno de sus recursos principales es la cita; es Adagio con variaciones donde claramente observaremos la memoria lejana e inmediata al tiempo: Wagner es el punto de referencia al pasado, Wolf impulsa hacia el presente, y, Aracil advierte el devenir en cada una de sus variaciones.

  19. Considerations over the effects caused by a heat recovery system for exhaust gases, adapted to gas turbines originally designed for the operation in a simple cycle; Consideraciones sobre los efectos causados por un sistema de recuperacion de calor de gases de escape, adaptado a turbinas de gas disenadas originalmente para operar bajo un ciclo simple

    Energy Technology Data Exchange (ETDEWEB)

    Cuesta Escobar, Cesar A. [Instituto Mexicano del Petroleo, Mexico, D. F. (Mexico)

    1994-12-31

    This article sets out the considerations on what a heat recovery system from exhaust gases, to already installed and in operation gas turbines, and that were not originally designed to operate with this system, can cause. The potential effects are set forth on the control systems, on the combustion chambers, and in the gas turbine blades, utilized for natural gas pumping or power generation in land installations or in offshore platforms in trying to adapt to them a regenerative cycle or a heating system. Observed effects, fundamentally in the flame stability loop, flow velocity, thermal intensity coefficient, air/fuel relationships and mass flow. Also are presented the consequences that primary production system would suffer, mainly due to the natural gas pumping reduction, the space availability, the fuel consumption, and the maximum amount of heat susceptible to be recovered, comparing the requirements of this in the system. [Espanol] En este articulo se plantean las consideraciones sobre lo que puede provocar un sistema de recuperacion de calor de gases de escape adaptado a turbinas de gas ya instaladas, operando y que no fueron disenadas originalmente para operar con este sistema. Se plantean los probables efectos en los sistemas de control, en las camaras de combustion y en los empaletados de las turbinas de gas usadas para bombeo de gas natural o generacion electrica en instalaciones de tierra o plataformas marinas, al tratar de adaptarseles un ciclo regenerativo o un sistema para calentamiento. Efectos observados, fundamentalmente, en el LOOP de estabilidad de flama, velocidad del flujo, coeficiente de intensidad termica, relaciones aire-combustible y flujo masico. Tambien se presentan las consecuencias que sufriria el sistema primario de produccion debido, principalmente, a la reduccion del bombeo de gas natural, a la disponibilidad de espacio, al consumo de combustible y a la cantidad maxima de calor susceptible de recuperarse, comparada con los

  20. Caloric expenditure of aerobic, resistance, or combined high-intensity interval training using a hydraulic resistance system in healthy men.

    Science.gov (United States)

    Falcone, Paul H; Tai, Chih-Yin; Carson, Laura R; Joy, Jordan M; Mosman, Matt M; McCann, Tyler R; Crona, Kevin P; Kim, Michael P; Moon, Jordan R

    2015-03-01

    Although exercise regimens vary in content and duration, few studies have compared the caloric expenditure of multiple exercise modalities with the same duration. The purpose of this study was to compare the energy expenditure of single sessions of resistance, aerobic, and combined exercise with the same duration. Nine recreationally active men (age: 25 ± 7 years; height: 181.6 ± 7.6 cm; weight: 86.6 ± 7.5 kg) performed the following 4 exercises for 30 minutes: a resistance training session using 75% of their 1-repetition maximum (1RM), an endurance cycling session at 70% maximum heart rate (HRmax), an endurance treadmill session at 70% HRmax, and a high-intensity interval training (HIIT) session on a hydraulic resistance system (HRS) that included repeating intervals of 20 seconds at maximum effort followed by 40 seconds of rest. Total caloric expenditure, substrate use, heart rate (HR), and rating of perceived exertion (RPE) were recorded. Caloric expenditure was significantly (p ≤ 0.05) greater when exercising with the HRS (12.62 ± 2.36 kcal·min), compared with when exercising with weights (8.83 ± 1.55 kcal·min), treadmill (9.48 ± 1.30 kcal·min), and cycling (9.23 ± 1.25 kcal·min). The average HR was significantly (p ≤ 0.05) greater with the HRS (156 ± 9 b·min), compared with that using weights (138 ± 16 b·min), treadmill (137 ± 5 b·min), and cycle (138 ± 6 b·min). Similarly, the average RPE was significantly (p ≤ 0.05) higher with the HRS (16 ± 2), compared with that using weights (13 ± 2), treadmill (10 ± 2), and cycle (11 ± 1). These data suggest that individuals can burn more calories performing an HIIT session with an HRS than spending the same amount of time performing a steady-state exercise session. This form of exercise intervention may be beneficial to individuals who want to gain the benefits of both resistance and cardiovascular training but have limited time to dedicate to exercise.

  1. Flow prediction and heat transfer in a cooling square duch of a gas turbine blade using CFD; Predicciones de flujo y transferencia de calor en un conductor de alabe enfriado de turbina de gas utilizando CFD

    Energy Technology Data Exchange (ETDEWEB)

    Urquiza B, Gustavo [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Sierra E, Fernando [Universidad Nacional Autonoma de Mexico, Mexico D.F. (Mexico); Kubiak S, Janusz; Campos A, Rafael [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2003-10-15

    A numerical investigation has been conducted to study the turbulent flow and the heat transfer in a blade turbine coolant passage involving a 180 degrees turn. The study provides a comparison test for two turbulence models. The numerical solution was conducted employing two models for turbulence, the renormalization Group Theory (RNG) and the Reynolds Stress Model (RSM), using a refined grid to model with detail the recirculating flow. Computations are performed with a commercial finite volume code which solves three dimensional, incompressible, Navier-Stokes and Energy equations. At the passage turn, significant secondary flows are present, formed by a pair of symmetrical vortices. Results have been compared against published experimental data for Re = 53 000. Very good agreement is achieved for the prediction of the local static pressure distribution along the passage. A strong effect of rotation has been observed mainly in the flow field as described in detail in the paper. [Spanish] En este trabajo se presenta una investigacion numerica para estudiar el flujo turbulento y la transferencia de calor en un conducto de enfriamiento de un alabes de turbina de gas con giro de 180 grados. El estudio proporciona una comparacion de resultados para dos modelos de turbulencia. La solucion numerica emplea dos modelos de turbulencia: el modelo de esfuerzos de Reynolds (RSM) y el modelo de la teoria del grupo de renormalizacion (RNG), utilizando una malla refinada para modelar con detalle el flujo de recirculacion. Los calculos fueron realizados con un codigo comercial de volumenes finitos el cual resuelve las ecuaciones tridimensionales de Navier-Stoke y de energia para flujo incompresible. En la seccion de giro del conductor, aparecen flujos secundarios significativos, formados por un par de celulas simetricas. Los resultados han sido comparados contra datos experimentales de la literatura para Re = 53 000. se obtuvo un buen acuerdo para la prediccion de la distribucion de

  2. Entrevista con Hans Robert Jauss.

    Directory of Open Access Journals (Sweden)

    - Consejo de Redacción

    1997-01-01

    Full Text Available El importante teórico y crítico literario alemán nació en 1921. Tras el largo paréntesis de la segunda guerra mundial, Jauss realizará sus estudios superiores, a partir de 1948, en Heidelberg, licenciándose en filología románica. Se doctora pronto con una tesis, publicada en 1955, sobre el tiempo y el recuerdo en la obra capital de Marcel Proust, En busca del tiempo perdido, y se habilita en 1957 con un trabajo sobre la epopeya animal en la Edad Media. A continuación, escribe un conjunto de estudios sobre la alegoría, y codirige con el gran especialista Erich Kohler una monumental historia de la literatura medieval, campo al que ha dedicado otros artículos, a la par que proseguía sus investigaciones iniciales.

  3. Tratamiento con implantes Leader-Nano en paciente con oligodoncia

    Directory of Open Access Journals (Sweden)

    Salvador Javier Santos Medina

    2015-03-01

    Full Text Available Los implantes dentales de titanio han revolucionado el mundo de la rehabilitación desde su surgimiento. De manera particular, el empleo de implantes de carga inmediata acorta el tiempo quirúrgico y protésico, con el consiguiente bienestar estético. Se presenta el caso de una paciente femenina de 32 años de edad, con antecedentes de oligodoncia de ambos incisivos laterales superiores y portadora de prótesis parcial acrílica. Fue atendida por el equipo multidisciplinario de implantes en la Clínica Estomatológica Docente “3 de Octubre” y se le realizó tratamiento de rehabilitación integral con implantes Leader-Nano y prótesis fija con corona acrílica sobre dichos implantes. La implantología fue satisfactoria en la paciente; la mejoría estética y funcional, así como la satisfacción de la paciente, fueron los principales logros obtenidos

  4. Caloric Restriction reduces inflammation and improves T cell-mediated immune response in obese mice but concomitant consumption of curcumin/piperine adds no further benefit

    Science.gov (United States)

    Obesity is associated with low-grade inflammation and impaired immune response. Caloric restriction (CR) has been shown to inhibit inflammatory response and enhance cell-mediated immune function. Curcumin, the bioactive phenolic component of turmeric spice, is proposed to have anti-obesity and anti-...

  5. Roles of caloric restriction, ketogenic diet and intermittent fasting during initiation, progression and metastasis of cancer in animal models: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Mengmeng Lv

    Full Text Available The role of dietary restriction regimens such as caloric restriction, ketogenic diet and intermittent fasting in development of cancers has been detected via abundant preclinical experiments. However, the conclusions are controversial. We aim to review the relevant animal studies systematically and provide assistance for further clinical studies.Literatures on associations between dietary restriction and cancer published in PubMed in recent twenty years were comprehensively searched. Animal model, tumor type, feeding regimen, study length, sample size, major outcome, conclusion, quality assessment score and the interferential step of cancer were extracted from each eligible study. We analyzed the tumor incidence rates from 21 studies about caloric restriction.Fifty-nine studies were involved in our system review. The involved studies explored roles of dietary restriction during initiation, progression and metastasis of cancer. About 90.9% of the relevant studies showed that caloric restriction plays an anti-cancer role, with the pooled OR (95%CI of 0.20 (0.12, 0.34 relative to controls. Ketogenic diet was also positively associated with cancer, which was indicated by eight of the nine studies. However, 37.5% of the related studies obtained a negative conclusion that intermittent fasting was not significantly preventive against cancer.Caloric restriction and ketogenic diet are effective against cancer in animal experiments while the role of intermittent fasting is doubtful and still needs exploration. More clinical experiments are needed and more suitable patterns for humans should be investigated.

  6. Is less always more? The effects of low-fat labeling and caloric information on food intake, calorie estimates, taste preference, and health attributions.

    Science.gov (United States)

    Ebneter, Daria S; Latner, Janet D; Nigg, Claudio R

    2013-09-01

    The present study examined whether low-fat labeling and caloric information affect food intake, calorie estimates, taste preference, and health perceptions. Participants included 175 female undergraduate students who were randomly assigned to one of four experimental conditions. A 2×2 between subjects factorial design was used in which the fat content label and caloric information of chocolate candy was manipulated. The differences in food intake across conditions did not reach statistical significance. However, participants significantly underestimated the calorie content of low-fat-labeled candy. Participants also rated low-fat-labeled candy as significantly better tasting when they had caloric information available. Participants endorsed more positive health attributions for low-fat-labeled candy than for regular-labeled candy, independent of caloric information. The inclusion of eating attitudes and behaviors as covariates did not alter the results. The study findings may be related to the "health halo" associated with low-fat foods and add to the research base by examining the interaction between low-fat and calorie labeling.

  7. A Multi-stage Carcinogenesis Model to Investigate Caloric Restriction as a Potential Tool for Post-irradiation Mitigation of Cancer Risk

    Science.gov (United States)

    Tani, Shusuke; Blyth, Benjamin John; Shang, Yi; Morioka, Takamitsu; Kakinuma, Shizuko; Shimada, Yoshiya

    2016-01-01

    The risk of radiation-induced cancer adds to anxiety in low-dose exposed populations. Safe and effective lifestyle changes which can help mitigate excess cancer risk might provide exposed individuals the opportunity to pro-actively reduce their cancer risk, and improve mental health and well-being. Here, we applied a mathematical multi-stage carcinogenesis model to the mouse lifespan data using adult-onset caloric restriction following irradiation in early life. We re-evaluated autopsy records with a veterinary pathologist to determine which tumors were the probable causes of death in order to calculate age-specific mortality. The model revealed that in both irradiated and unirradiated mice, caloric restriction reduced the age-specific mortality of all solid tumors and hepatocellular carcinomas across most of the lifespan, with the mortality rate dependent more on age owing to an increase in the number of predicted rate-limiting steps. Conversely, irradiation did not significantly alter the number of steps, but did increase the overall transition rate between the steps. We show that the extent of the protective effect of caloric restriction is independent of the induction of cancer from radiation exposure, and discuss future avenues of research to explore the utility of caloric restriction as an example of a potential post-irradiation mitigation strategy. PMID:27390741

  8. Carlstad Comic Con : En fallstudie

    OpenAIRE

    Fors, Marcus Gabriel

    2013-01-01

    This is a case study of Carlstad Comic Con 2011 and 2012.The purpose is to study the event in relation to a project management and a local culture policy perspective. This in order to analyze the organization of a popular culture event and see how such a local event may benefit Karlstad as a city. Besides studying the organization of Carlstad Comic Con and its outcomes I am sketching a short cultural history of popular culture media and its context within recent year’s globalization.The study...

  9. Energía geotérmica : "el calor robado a la tierra"

    OpenAIRE

    HEREDIA BENITO, JUANA

    2014-01-01

    La energía geotérmica está considerada como renovable, y es muy conocida en países donde existe una gran demanda de calefacción como Alemania o los países nórdicos. En el presente TFG se pretende dar una visión más práctica del principal uso que tiene esta energía: la climatización de edificios. El proyecto consta de una primera parte teórica donde se hace una introducción a la energía geotérmica a lo largo de la historia, se vincula con el desarrollo sostenible y se da a conocer la repercusi...

  10. SÍNTESIS DE REDES DE INTERCAMBIO DE CALOR USANDO EQUIPO ESTÁNDAR

    OpenAIRE

    Arroyo López, Víctor Hugo

    2012-01-01

    El ahorro de energía es considerado una prioridad en la etapa de diseño de nuevas plantas de proceso y en el reajuste de las ya existentes. Sin embargo, la mayoría de las metodologías reportadas para la solución de estos problemas consideran coeficientes de película supuestos en base a la experiencia del diseñador y no toman en cuenta la interrelación que guardan las caídas de presión de los quipos con el diseño detallado para el cálculo de los coeficientes de transferencia de ...

  11. Distinct lipid profiles predict improved glycemic control in obese, nondiabetic patients after a low-caloric diet intervention

    DEFF Research Database (Denmark)

    Valsesia, Armand; Saris, Wim Hm; Astrup, Arne;

    2016-01-01

    improvement. DESIGN: We investigated the plasma lipidome of 383 obese, nondiabetic patients within a randomized, controlled dietary intervention in 8 European countries at baseline, after an 8-wk low-caloric diet (LCD) (800-1000 kcal/d), and after 6 mo of weight maintenance. RESULTS: After weight loss......, a lipid signature identified 2 groups of patients who were comparable at baseline but who differed in their capacities to lose weight and improve glycemic control. Six months after the LCD, one group had significant glycemic improvement [homeostasis model assessment of insulin resistance (HOMA-IR) mean...... change: -0.92; 95% CI: -1.17, -0.67)]. The other group showed no improvement in glycemic control (HOMA-IR mean change: -0.26; 95% CI: -0.64, +0.13). These differences were sustained for ≥1 y after the LCD. The same conclusions were obtained with other endpoints (Matsuda index and fasting insulin...

  12. Humedad de equilibrio y calor latente de vaporización del ajonjolí. Sésamun indicum L.

    Directory of Open Access Journals (Sweden)

    Julio E. Ospina M.

    2011-06-01

    Full Text Available El ajonjolí (Sésamun indicum L., es una oleaginosa originaria de África y cultivada en las regiones tropicales y subtropicales de Asia y América. A los 110 días de sembrada se cosecha la semilla la cual se utiliza como materia prima especialmente en la industria de grasas y aceites comestibles. Actualmente se pierden en Colombia, un alto porcentaje de semillas durante el proceso de secado natura en el campo. Debido a la falta de información técnica, científica en secado y almacenamiento del grana de ajonjolí se procedió a estudiar la metodología para determinar, el contenido de humedad por el método de la estufa, las curvas y modelo para cuantificar la humedad de equilibrio y el calor latente de vaporización.

  13. [Effeciency of usage of natural low caloric protein-vegetable product by patients with excess body weight and hypertension].

    Science.gov (United States)

    Rakhmanov, R S; Istomin, A V; Narutdinov, D A; Kropachev, V Iu

    2014-01-01

    The efficiency of the usage of natural low caloric concentrated protein-vegetable food product (LCCF) by 23 persons with excess body weight at the age of 30-44 years (the 1st group) and 30 hypertensive patients at remission stage and overweight at age 45-59 years old (the 2nd group) has been assessed. According to energy expenditure, all examined male persons were classified to II group of physical activity: PhysicalActivity Coefficient (PAC) was 1,35±0,14 and 1,34±0,22 respectively. As for dietary intake, authors revealed an excess of protein (up to 20,1%), fat (up to 17,2%) and daily caloric content over daily energy expenditure that led to an increase of body weight along with metabolic and liver function disorders. Initially, body mass index (BMI) was 29,9±0,6 kg/m2 in the 1st group and 36,2±0,4 kg/m2 in the 2nd group. LCCFP was administrated to persons in studied groups and consisted of fat-free curd, egg white, rye bran, dried apricots, laminaria, leaves of green tea and cowberry. The product was made by cryogenic technology. LCCFP (35 g) was administrated two times per day instead of breakfast and supper during 15 days. Protein content in 1 portion of LCCFP was 5.2 g, fats -3.8 g, carbohydrates - 16.8 g; energy value - 122 kcal. The decrease of daily caloric content was 1225,5 kilocalories (kcal) in the 1st group and 1071,3 kcal in the 2nd group duringperiod of LCCFP administration; the energy value of the diet amounted to an average of 1420 and 1560 kcal per day. During the study, authors found serum protein indices were constant, but revealed the decrease of the level of glucose (by 15,3-18%), cholesterol (18,8-19%), low density lipoprotein cholesterol (13,9-15,8%), triglycerides (20-26,3%) and alanine aminotransferase (39,7-41,4%) and asparagine aminotransferase (40,6-40,7%) activity. This provided evidence of positive influence of the natural protein-vegetable LCCFP on fat and carbohydrate metabolisms as well as liver function. Also, the decrease of

  14. Effects of caloric restriction on learning and recovery of a spatial task in rats exposed to acute stress

    Directory of Open Access Journals (Sweden)

    Lamprea Rodríguez, Marisol

    2009-06-01

    Full Text Available The purpose of the present study was to describe the effects of caloric restriction on spatial learning and recovery in the Barnes maze in animals experimentally stressed before recovery of the spatial task. Male Wistar rats were exposed for two months to one of two conditions: ad libitum (AL or intermittent fasting (IF. Both groups were exposed then to an experimental form of acute stress, induced by movement restriction for 4 hours. IF subjects had better performance in learning tasks during the acquisition trials but required more time to complete the task after the stressor was applied. These results are discussed in light of previous data reported in the literature emphasizing differences in the instruments used to evaluate spatial learning and its interaction with experimentally induced stress.

  15. con dietas suplementadas con Cromo-L-metionina

    Directory of Open Access Journals (Sweden)

    Ram\\u00F3n Garc\\u00EDa-Castillo

    2006-01-01

    Full Text Available Un total de 48 cerdos (Sus scrofa domesticus; 24 machos castrados y 24 hembras cruzados (Yorkshire, Hampshire, Duroc y Landrace de 3,5 a 4,0 meses de edad y 60,0 ± 5,0 kg PV en finalización. Se alimentaron con dietas isoproteícas (14,5 % PC e isoenergéticas (3.400 kcal EM/kg de MS, adicionadas con Cr-L-metionina (MiCroPlex® (0, 200, 400 y 600 ppb. El experimento tuvo una duración de 45 días y se realizó de agosto a noviembre del 2002 en las instalaciones de la Universidad Autónoma Agraria Antonio Narro, localizada en Saltillo, Coahuila, México. Al tener los animales aproximadamente 95 kg PV, se tomó muestra de 15 ml de sangre por cada animal para determinar la concentración de glucosa, ácido úrico, creatinina, urea, proteinas totales y colesterol. Se aplicó un diseño completamente al azar con arreglo factorial 2 x 4; dos para el factor sexo y cuatro para nivel de cromo. Los metabolitos en suero no fueron afectados (P>0,05 por el factor sexo. La glucosa en suero disminuyó (P<0,05 y el colesterol incrementó (P<0,05 con cromo en la dieta. Se concluye que el Cr incrementa el metabolismo de glucosa y disminuye el de colesterol, con lo cual puede haber energía disponible para síntesis de proteína la cual es necesaria para el crecimiento de los animales

  16. Effects of 12 weeks of combined training without caloric restriction on inflammatory markers in overweight girls.

    Science.gov (United States)

    Lopes, Wendell Arthur; Leite, Neiva; da Silva, Larissa Rosa; Brunelli, Diego Trevisan; Gáspari, Arthur Fernandes; Radominski, Rosana Bento; Chacon-Mikahil, Mara Patrícia Traina; Cavaglieri, Cláudia Regina

    2016-10-01

    The objective of the present study was to investigate the effects of combined training without caloric restriction on inflammatory markers in overweight girls. Thirty-three girls (13-17 years) were assigned into overweight training (n = 17) or overweight control (n = 16) groups. Additionally, a normal-weight group (n = 15) was used as control for the baseline values. The combined training programme consisted of six resistance exercises (three sets of 6-10 repetitions at 60-70% 1 RM) followed by 30 min of aerobic exercise (walking/running) at 50-80% VO2peak, performed in the same 60 min session, 3 days/weeks, for 12 weeks. Body composition, dietary intake, aerobic fitness (VO2peak), muscular strength (1 RM), glycaemia, insulinemia, lipid profile and inflammatory markers (C-reactive protein, interleukin-6, tumour necrosis factor-alpha, interleukin-10, leptin, resistin and adiponectin) were measured before and after intervention. There was a significant decrease in body fat (P < 0.01) and increase in fat-free mass (P < 0.01), VO2peak (P < 0.01), 1 RM for leg press (P < 0.01) and bench press (P < 0.01) in the overweight training group. Concomitantly, this group presented significant decreases in serum concentrations of C-reactive protein (P < 0.05) and leptin (P < 0.05), as well as in insulin resistance (P < 0.05) after the experimental period. In conclusion, 12 weeks of combined training without caloric restriction reduced inflammatory markers associated with obesity in overweight girls. PMID:26852885

  17. Effects of 12 weeks of combined training without caloric restriction on inflammatory markers in overweight girls.

    Science.gov (United States)

    Lopes, Wendell Arthur; Leite, Neiva; da Silva, Larissa Rosa; Brunelli, Diego Trevisan; Gáspari, Arthur Fernandes; Radominski, Rosana Bento; Chacon-Mikahil, Mara Patrícia Traina; Cavaglieri, Cláudia Regina

    2016-10-01

    The objective of the present study was to investigate the effects of combined training without caloric restriction on inflammatory markers in overweight girls. Thirty-three girls (13-17 years) were assigned into overweight training (n = 17) or overweight control (n = 16) groups. Additionally, a normal-weight group (n = 15) was used as control for the baseline values. The combined training programme consisted of six resistance exercises (three sets of 6-10 repetitions at 60-70% 1 RM) followed by 30 min of aerobic exercise (walking/running) at 50-80% VO2peak, performed in the same 60 min session, 3 days/weeks, for 12 weeks. Body composition, dietary intake, aerobic fitness (VO2peak), muscular strength (1 RM), glycaemia, insulinemia, lipid profile and inflammatory markers (C-reactive protein, interleukin-6, tumour necrosis factor-alpha, interleukin-10, leptin, resistin and adiponectin) were measured before and after intervention. There was a significant decrease in body fat (P < 0.01) and increase in fat-free mass (P < 0.01), VO2peak (P < 0.01), 1 RM for leg press (P < 0.01) and bench press (P < 0.01) in the overweight training group. Concomitantly, this group presented significant decreases in serum concentrations of C-reactive protein (P < 0.05) and leptin (P < 0.05), as well as in insulin resistance (P < 0.05) after the experimental period. In conclusion, 12 weeks of combined training without caloric restriction reduced inflammatory markers associated with obesity in overweight girls.

  18. Feed restriction and a diet's caloric value: The influence on the aerobic and anaerobic capacity of rats

    Directory of Open Access Journals (Sweden)

    de Moura Leandro

    2012-03-01

    Full Text Available Abstract Background The influence of feed restriction and different diet's caloric value on the aerobic and anaerobic capacity is unclear in the literature. Thus, the objectives of this study were to determine the possible influences of two diets with different caloric values and the influence of feed restriction on the aerobic (anaerobic threshold: AT and anaerobic (time to exhaustion: Tlim variables measured by a lactate minimum test (LM in rats. Methods We used 40 adult Wistar rats. The animals were divided into four groups: ad libitum commercial Purina® diet (3028.0 Kcal/kg (ALP, restricted commercial Purina® diet (RAP, ad libitum semi-purified AIN-93 diet (3802.7 Kcal/kg (ALD and restricted semi-purified AIN-93 diet (RAD. The animals performed LM at the end of the experiment, 48 h before euthanasia. Comparisons between groups were performed by analysis of variance (p Results At the end of the experiment, the weights of the rats in the groups with the restricted diets were significantly lower than those in the groups with ad libitum diet intakes. In addition, the ALD group had higher amounts of adipose tissue. With respect to energetic substrates, the groups subjected to diet restriction had significantly higher levels of liver and muscle glycogen. There were no differences between the groups with respect to AT; however, the ALD group had lower lactatemia at the AT intensity and higher Tlim than the other groups. Conclusions We conclude that dietary restriction induces changes in energetic substrates and that ad libitum intake of a semi-purified AIN-93 diet results in an increase in adipose tissue, likely reducing the density of the animals in water and favouring their performance during the swimming exercises.

  19. Caloric restriction and intermittent fasting alter hepatic lipid droplet proteome and diacylglycerol species and prevent diabetes in NZO mice.

    Science.gov (United States)

    Baumeier, Christian; Kaiser, Daniel; Heeren, Jörg; Scheja, Ludger; John, Clara; Weise, Christoph; Eravci, Murat; Lagerpusch, Merit; Schulze, Gunnar; Joost, Hans-Georg; Schwenk, Robert Wolfgang; Schürmann, Annette

    2015-05-01

    Caloric restriction and intermittent fasting are known to improve glucose homeostasis and insulin resistance in several species including humans. The aim of this study was to unravel potential mechanisms by which these interventions improve insulin sensitivity and protect from type 2 diabetes. Diabetes-susceptible New Zealand Obese mice were either 10% calorie restricted (CR) or fasted every other day (IF), and compared to ad libitum (AL) fed control mice. AL mice showed a diabetes prevalence of 43%, whereas mice under CR and IF were completely protected against hyperglycemia. Proteomic analysis of hepatic lipid droplets revealed significantly higher levels of PSMD9 (co-activator Bridge-1), MIF (macrophage migration inhibitor factor), TCEB2 (transcription elongation factor B (SIII), polypeptide 2), ACY1 (aminoacylase 1) and FABP5 (fatty acid binding protein 5), and a marked reduction of GSTA3 (glutathione S-transferase alpha 3) in samples of CR and IF mice. In addition, accumulation of diacylglycerols (DAGs) was significantly reduced in livers of IF mice (P=0.045) while CR mice showed a similar tendency (P=0.062). In particular, 9 DAG species were significantly reduced in response to IF, of which DAG-40:4 and DAG-40:7 also showed significant effects after CR. This was associated with a decreased PKCε activation and might explain the improved insulin sensitivity. In conclusion, our data indicate that protection against diabetes upon caloric restriction and intermittent fasting associates with a modulation of lipid droplet protein composition and reduction of intracellular DAG species. PMID:25645620

  20. PREFACE: XIII International Conference on Calorimetry in High Energy Physics (CALOR 2008)

    Science.gov (United States)

    Livan, Michele

    2009-07-01

    The XIII International Conference on Calorimetry in High Energy Physics was held in Pavia, Italy, 26-30 May 2008, picking up the baton from the 2006 Conference in Chicago. The Conference took place in the unique environment of the Theresian Room of the University Library. The attendees were surrounded by over 40 000 books of general interest and culture, and had the opportunity to see precious volumes written by such people as Galileo, Volta and Faraday. The Workshop brought together more than 120 participants, including senior scientists as well as young physicists, confirming the central and ever-growing role of calorimeters in modern particle physics. The development of these detectors, as stressed by Professor Klaus Pretzl in his lectio magistralis, has made it possible to explore new frontiers in physics, and the present scenario is no exception to this rule. With the LHC experiments almost completely installed and ready to take data, the Conference was an ideal chance to review the status of the different projects, whose development has been followed and discussed throughout the entire Calor series, and to show that they are capable of meeting the design specifications. Other highlights were the performance and physics results of calorimeters installed in currently operating experiments. In the session on astrophysics and neutrinos, the contributions confirmed the key role of calorimeters in this sector and demonstrated their growing application even beyond the field of accelerator physics. Considerable time was devoted to the state-of-the-art techniques in the design and operation of the detectors, while the session on simulation addressed the importance of a thorough understanding of the shower development to meet the demanding requirements of present experiments. Finally, on the R&D side, the particle flow and dual read-out concepts confronted the challenges issued by the next generation of experiments. This complex material was reviewed in 83

  1. Influence of aging and long-term caloric restriction on oxygen radical generation and oxidative DNA damage in rat liver mitochondria.

    Science.gov (United States)

    López-Torres, Mónica; Gredilla, Ricardo; Sanz, Alberto; Barja, Gustavo

    2002-05-01

    The effect of long-term caloric restriction and aging on the rates of mitochondrial H2O2 production and oxygen consumption as well as on oxidative damage to nuclear (nDNA) and mitochondrial DNA (mtDNA) was studied in rat liver tissue. Long-term caloric restriction significantly decreased H2O2 production of rat liver mitochondria (47% reduction) and significantly reduced oxidative damage to mtDNA (46% reduction) with no changes in nDNA. The decrease in ROS production was located at complex I because it only took place with complex I-linked substrates (pyruvate/malate) but not with complex II-linked substrates (succinate). The mechanism responsible for that decrease in ROS production was not a decrease in mitochondrial oxygen consumption because it did not change after long-term restriction. Instead, the caloric restricted mitochondria released less ROS per unit electron flow, due to a decrease in the reduction degree of the complex I generator. On the other hand, increased ROS production with aging in state 3 was observed in succinate-supplemented mitochondria because old control animals were unable to suppress H2O2 production during the energy transition from state 4 to state 3. The levels of 8-oxodG in mtDNA increased with age in old animals and this increase was abolished by caloric restriction. These results support the idea that caloric restriction reduces the aging rate at least in part by decreasing the rate of mitochondrial ROS production and so, the rate of oxidative attack to biological macromolecules like mtDNA. PMID:11978489

  2. Long-term hyperphagia and caloric restriction caused by low- or high-density husbandry have differential effects on zebrafish postembryonic development, somatic growth, fat accumulation and reproduction.

    Directory of Open Access Journals (Sweden)

    Sandra Leibold

    Full Text Available In recent years, the zebrafish (Danio rerio has emerged as an alternative vertebrate model for energy homeostasis and metabolic diseases, including obesity and anorexia. It has been shown that diet-induced obesity (DIO in zebrafish shares multiple pathophysiological features with obesity in mammals. However, a systematic and comprehensive analysis of the different pathways of energy expenditure in obese and starved fish had been missing thus far. Here, we carry out long-term ad libitum feeding (hyperphagia and caloric restriction studies induced by low- or high-density husbandry, respectively, to investigate the impact of caloric intake on the timing of scale formation, a crucial step of postembryonic development and metamorphosis, and on somatic growth, body weight, fat storage and female reproduction. We show that all of them are positively affected by increased caloric intake, that middle-aged fish develop severe DIO, and that the body mass index (BMI displays a strict linear correlation with whole-body triglyceride levels in adult zebrafish. Interestingly, juvenile fish are largely resistant to DIO, while BMI and triglyceride values drop in aged fish, pointing to aging-associated anorexic effects. Histological analyses further indicate that increased fat storage in white adipose tissue involves both hyperplasia and hypertrophy of adipocytes. Furthermore, in ovaries, caloric intake primarily affects the rate of oocyte growth, rather than total oocyte numbers. Finally, comparing the different pathways of energy expenditure with each other, we demonstrate that they are differentially affected by caloric restriction / high-density husbandry. In juvenile fish, scale formation is prioritized over somatic growth, while in sexually mature adults, female reproduction is prioritized over somatic growth, and somatic growth over fat storage. Our data will serve as a template for future functional studies to dissect the neuroendocrine regulators of

  3. Juegos con monedas y palillos

    OpenAIRE

    Cobarro, Trinidad

    1993-01-01

    Es frecuente entre nosotros, los que nos dedicamos a la enseñanza de las matemáticas por muy grande que sea nuestro amor por la materia y el deseo de comunicación, nos encontrarnos con un problema: ¿cómo mantener interesados a los alumnos?

  4. Comportamiento Termodinámico de un ORC operando con varias sustancias para el aprovechamiento de Fuentes Térmicas de Bajo Potencial

    OpenAIRE

    Artemio de Jesús Benítez Fundora

    2011-01-01

    En  el  presente  artículo,  se  m uestra  el  estudio  preliminar  relacionado  con  la  selección  y propuesta  de  varios  fluidos  para  operar  un  Ciclo  Rankine  Orgánico  (ORC)  con  el  fin  de recuperar el calor de desperdicio de fuentes industriales. El  principal  criterio de selección fue definido  tenien...

  5. Investigación teórico - experimental del desempeño de un motor HCCI operado con Etanol Anhidro [E100] E hidratado [E80

    OpenAIRE

    Támara Jaramillo, José David

    2013-01-01

    En este estudio se evaluó el desempeño de un motor HCCI operado con etanol anhidro [E100] y etanol hidratado [E80], para ello se implementó un modelo CFD con cinética de reacción sencilla para el etanol en el código CFD KIVA-4 R. Se determinó la presión interna, la liberación de calor, el inicio de la combustión, el CA50 y la duración de la combustión (HRD), como las eficiencias térmicas y de la combustión en función de la temperatura de admisión, la relación de compresión y la relación de eq...

  6. La atención a los padres con hijos con necesidades educativas especiales (NEE)

    OpenAIRE

    Claudia María Pernas Pico

    2011-01-01

    Los padres que tienen hijos con necesidades educativas especiales (NEE) necesitan al igual que sus hijos de la intervención del maestro de Audición y Lenguaje con el objetivo primordial de mejorar la comunicación y el lenguaje de los niños. Se pretende en este artículo dar un abanico de posibilidades de cómo se puede intervenir con los padres desde las escuelas: con largas horas de reuniones, con formación, con talleres, con actividades y juegos, con libretas viajeras, con pequeñas pautas, et...

  7. Relations between Main Wood Chemical Compositions and the Caloric Value of Robinia pseudoacacia Cl.‘Hennansis 8’%豫刺8号主要木材化学成分与热值的关系

    Institute of Scientific and Technical Information of China (English)

    赵静; 彭祚登; 江丽媛; 孙龙; 谭晓红

    2013-01-01

    Gross caloric values,ash contents,ash-free caloric values,cellulose,hemicellulose,lignin and benzenealcohol extract contents were studied at different growth stages and in various organs of Robinia pseudoacacia C1.' Hennansis 8'.Results showed that:the leaf had the highest average gross caloric values and ash-free caloric values,and these values were relatively higher at the initial growth stage of the next year among the sampling period of time; the leaf had the highest average ash contents,and the contents were higher at the late stage of the next year.The orders of cellulose and hemicellulose contents were all trunk > branch > bark > leaf.The leaf had the most lignin,benzene-alcohol extract contents.Benzene-alcohol extract contents were appeared to be an inverted V distribution with the growth stages.Gross caloric values were not significantly negatively correlated with ash contents,cellulose and hemicellulose contents,and they were significantly correlated with lignin but not significantly with benzene-alcohol extract contents;Ash-free caloric values were significantly negatively correlated with cellulose and hemicellulose contents,and were significantly correlated with lignin and benzene-alcohol extract contents.In terms of the variation of caloric values,the best cutting period for energy forests was the initial growth stage of the next year among the five growth stages of ' Hennansis 8'

  8. Efecto de la Modificación del Microclima y la Inyección de Somatotropina Bovina (Stb Sobre Variables Productivas y Fisiológicas de Vacas Holstein Estresadas por el Calor Durante el Verano.

    Directory of Open Access Journals (Sweden)

    Mario Antonio Tarazón Herrera

    2005-01-01

    Full Text Available Las condiciones metereológicas y algunos factores ligados al animal influencian la producción de leche de las vacas. También, es bien conocido que la inyección de la hormona Somatotropina bovina aumenta la producción de leche y mejora la eficiencia alimenticia. Treinta y dos vacas Holstein (ocho por tratamiento promediando 195 días en lactancia fueron asignadas a un periodo de tratamiento de 70 días sobre la base de producción de leche durante los 14 días del pretratamiento, el cual fue usado para correr un análisis de covarianza. El diseño de experimento fue bloques al azar con un arreglo de tratamientos factorial 2x2. Los factores fueron la sombra o la sombra más un enfriador evaporativo con spray presurizado, con y sin la administración de Somatotropina bovina (STb. Las vacas que recibieron la STb fueron inyectadas con 500 mg cada 14 días. Todas las vacas fueron alimentadas dos veces al día con la misma ración con un 10% adicional al consumo estimado y el agua fue ofrecida a libre consumo. No hubo interacciones entre la STb y el sistema de enfriamiento para ninguna de las variables evaluadas. La STb y el enfriador evaporativo aumentaron la producción de leche de las vacas. Los porcentajes de grasa en la leche y las producciones de grasa y proteína en la leche y la producción de leche corregida (a 3.5 % de grasa y la eficiencia en la conversión de materia seca de ración a leche corregida, también fueron aumentados por la STb; mientras que el enfriador evaporativo aumentó los pesos corporales y las producciones de proteína de la leche, pero disminuyó los sólidos no grasos y los porcentajes de proteína en la leche. Las temperaturas rectales y las tasas de respiración también decrecieron con el enfriador evaporativo. La STb aumentó los ácidos grasos no esterificados de la sangre, sugiriendo que parte de la energía adicional de la producción de leche aumentada provino de la movilización de grasa corporal. La

  9. Literatura con mayúsculas

    Directory of Open Access Journals (Sweden)

    Cerrillo, P.

    2006-11-01

    Full Text Available En este trabajo se presenta un acercamiento alconcepto de la Literatura Infantil y Juvenil a travésde una breve visión diacrítica desde sus orígeneshasta nuestros días, subrayando los usos particularesmás característicos de esta literatura en cadaépoca (didáctico, doctrinal, proselitista…. Ademásde señalar sus coincidencias con la Literatura engeneral, se pone también de relieve sus particularidadesy características específicas, en lo que noes sino un nuevo intento de delimitar la caracterizaciónde la LIJ (contenidos, temática, estructuraliteraria, forma, ediciones… y reivindicar estaLiteratura con mayúsculas.

  10. Alumnos con necesidades educativas especiales

    OpenAIRE

    Álvarez Pérez, Luis

    1995-01-01

    El objetivo de este trabajo es delimitar el concepto de alumno con necesidades educativas especiales y determinar como se tiene que abordar su educación en el marco del proyecto educativo de centro. Además se pretende establecer un modelo operativo para consignar las adaptaciones curriculares que sea preciso adoptar en función de las orientaciones establecidas en la evaluación previa

  11. Exercise training improves relaxation response and SOD-1 expression in aortic and mesenteric rings from high caloric diet-fed rats

    Directory of Open Access Journals (Sweden)

    Antunes Edson

    2008-05-01

    Full Text Available Abstract Background Obesity has been associated with a variety of disease such as type II diabetes mellitus, arterial hypertension and atherosclerosis. Evidences have shown that exercise training promotes beneficial effects on these disorders, but the underlying mechanisms are not fully understood. The aim of this study was to investigate whether physical preconditioning prevents the deleterious effect of high caloric diet in vascular reactivity of rat aortic and mesenteric rings. Methods Male Wistar rats were divided into sedentary (SD; trained (TR; sedentary diet (SDD and trained diet (TRD groups. Run training (RT was performed in sessions of 60 min, 5 days/week for 12 weeks (70–80% VO2max. Triglycerides, glucose, insulin and nitrite/nitrate concentrations (NOx- were measured. Concentration-response curves to acetylcholine (ACh and sodium nitroprusside (SNP were obtained. Expression of Cu/Zn superoxide dismutase (SOD-1 was assessed by Western blotting. Results High caloric diet increased triglycerides concentration (SDD: 216 ± 25 mg/dl and exercise training restored to the baseline value (TRD: 89 ± 9 mg/dl. Physical preconditioning significantly reduced insulin levels in both groups (TR: 0.54 ± 0.1 and TRD: 1.24 ± 0.3 ng/ml as compared to sedentary animals (SD: 0.87 ± 0.1 and SDD: 2.57 ± 0.3 ng/ml. On the other hand, glucose concentration was slightly increased by high caloric diet, and RT did not modify this parameter (SD: 126 ± 6; TR: 140 ± 8; SDD: 156 ± 8 and TRD 153 ± 9 mg/dl. Neither high caloric diet nor RT modified NOx- levels (SD: 27 ± 4; TR: 28 ± 6; SDD: 27 ± 3 and TRD: 30 ± 2 μM. Functional assays showed that high caloric diet impaired the relaxing response to ACh in mesenteric (about 13%, but not in aortic rings. RT improved the relaxing responses to ACh either in aortic (28%, for TR and 16%, to TRD groups or mesenteric rings (10%, for TR and 17%, to TRD groups that was accompanied by up-regulation of SOD-1

  12. con bajo peso al nacer

    Directory of Open Access Journals (Sweden)

    Adriana Mora Antó

    2005-01-01

    Full Text Available Esta investigación dio cuenta de la relación entre el estilo de funcionamiento familiar, los patrones de crianza y las edades de desarrollo evolutivo en niños, nacidos con bajo peso. El estudio descriptivo correlacional se realizó con 41 niños y sus madres, aplicándose cuestionarios sobre funcionamiento familiar, prácticas de crianza y desarrollo infantil. Los resultados señalaron la existencia de un funcionamiento familiar caracterizado por una cohesión amalgamada y una adaptabilidad caótica, una disciplina complaciente, falta de control y de límites claros en la díada madre-hijo. Se trataba de familias monoparentales, donde la temprana edad de concepción, el madresolterismo y el apoyo de la familia extensa eran constantes. Las edades evolutivas registradas indicaron un desarrollo inferior a la edad cronológica, en la mayor parte de los casos; sin embargo, éstas tendieron a ser superiores al compararlas con la edades reales de los infantes. No se encontró una correlación estadísticamente significativa entre la edad de desarrollo y los diferentes factores del funcionamiento familiar para algunos de los rangos de edad considerados; sin embargo, no se lo descartó por completo, especialmente en lo referente al optimismo familiar

  13. pacientes con insuficiencia renal terminal

    Directory of Open Access Journals (Sweden)

    Karen Herrera Herrera

    2011-01-01

    Full Text Available La presente investigación fundamenta en la clínica psicoanalítica el estudio de dos casos de tres personas diagnosticadas con IRT que reciben tratamiento de hemodiálisis, en razón a que dadas las características y el aumento de los reportes que se presentan, ya esto se considera un problema de salud pública. El objetivo principal es describir las características dinámicas del proceso de duelo en pacientes con IRT en un centro de terapia renal de la ciudad de Cartagena. El procedimiento metodológico empleó un diseño de tipo cualitativo; la investigación se desarrolló con un diseño clínico mediante el estudio de casos, y fundamentada en la hermenéutica psicoanalítica. Todo esto respaldado en la historia clínica, la entrevista semiestructurada individual y familiar, los test proyectivos, test del dibujo de la figura humana Machover y TAT de Murray, para la debida integración de los análisis. Se concluye que predominan funciones fallidas de los progenitores y que son individuos provenientes de familias psicosomáticas, que utilizan la enfermedad para obtener un beneficio secundario.

  14. Processes of heat transference during the construction of oil wells: inverse problem; Procesos de transferencia de calor durante la construccion de pozos petroleros: problema inverso

    Energy Technology Data Exchange (ETDEWEB)

    Olea Gonzalez, Ulises

    2007-08-15

    of the measured temperature. The result showed that the effects of the circulation losses were well modeled and the field of temperatures of the subsoil were satisfactorily reproduced. It can be concluded that the dynamic profiles of temperature obtained in five regions of the system well-formation, are a tool that can be applied as a support in the geologic control of the drilling, in the analysis of the factors that prevent the advance during the well drilling when dealing with relevant thermal effects, in the implementation of contingency programs or change of the design of the rheology of the drilling mud, in the control and quality of the used fluids and in the simulation of the zones with circulation losses of with the purpose of reducing the times caused by the stabilization period, diminution of the mud volumes and aid in the analysis of geo-pressures, among others. [Spanish] En la industria petrolera y durante la perforacion y terminacion de pozos petroleros, es indispensable contar con estimaciones confiables de temperaturas de la formacion; su relevancia y aplicacion se encuentra en muchas areas de la geofisica, de la ingenieria de yacimientos y de la ingenieria petrolera. Desafortunadamente, las temperaturas registradas durante las corridas normalmente son mas bajas que la temperatura real de formacion, esto se debe a que los tiempos de paro y circulacion de fluidos en el pozo son demasiado cortos de forma que no permiten que el lodo en el fondo del pozo alcance el equilibrio termico, lo cual requiere usualmente de varios dias o semanas, situacion economicamente no factible para determinar perfiles de temperatura, ya que los tiempos y costos de servicios de perforacion sobrepasarian los limites tecnicos economicos programados. Para afrontar este proceso critico se desarrollo un codigo numerico, el cual consiste en una solucion analitica y numerica de las ecuaciones de transferencia de calor que gobiernan un sistema pozo formacion, las cuales se utilizan

  15. Cardiac Sirt1 mediates the cardioprotective effect of caloric restriction by suppressing local complement system activation after ischemia-reperfusion.

    Science.gov (United States)

    Yamamoto, Tsunehisa; Tamaki, Kayoko; Shirakawa, Kohsuke; Ito, Kentaro; Yan, Xiaoxiang; Katsumata, Yoshinori; Anzai, Atsushi; Matsuhashi, Tomohiro; Endo, Jin; Inaba, Takaaki; Tsubota, Kazuo; Sano, Motoaki; Fukuda, Keiichi; Shinmura, Ken

    2016-04-15

    Caloric restriction (CR) confers cardioprotection against ischemia-reperfusion (I/R) injury. We previously found the essential roles of endothelial nitric oxide synthase in the development of CR-induced cardioprotection and Sirt1 activation during CR (Shinmura K, Tamaki K, Ito K, Yan X, Yamamoto T, Katsumata Y, Matsuhashi T, Sano M, Fukuda K, Suematsu M, Ishii I. Indispensable role of endothelial nitric oxide synthase in caloric restriction-induced cardioprotection against ischemia-reperfusion injury.Am J Physiol Heart Circ Physiol308: H894-H903, 2015). However, the exact mechanism by which Sirt1 in cardiomyocytes mediates the cardioprotective effect of CR remains undetermined. We subjected cardiomyocyte-specificSirt1knockout (CM-Sirt1(-/-)) mice and the corresponding control mice to either 3-mo ad libitum feeding or CR (-40%). Isolated perfused hearts were subjected to 25-min global ischemia, followed by 60-min reperfusion. The recovery of left ventricle function after I/R was improved, and total lactate dehydrogenase release into the perfusate during reperfusion was attenuated in the control mice treated with CR, but a similar cardioprotective effect of CR was not observed in the CM-Sirt1(-/-)mice. The expression levels of cardiac complement component 3 (C3) at baseline and the accumulation of C3 and its fragments in the ischemia-reperfused myocardium were attenuated by CR in the control mice, but not in the CM-Sirt1(-/-)mice. Resveratrol treatment also attenuated the expression levels of C3 protein in cultured neonatal rat ventricular cardiomyocytes. Moreover, the degree of myocardial I/R injury in conventionalC3knockout (C3(-/-)) mice treated with CR was similar to that in the ad libitum-fedC3(-/-)mice, although the expression levels of Sirt1 were enhanced by CR. These results demonstrate that cardiac Sirt1 plays an essential role in CR-induced cardioprotection against I/R injury by suppressing cardiac C3 expression. This is the first report suggesting that

  16. O estudo da prova calórica em pacientes idoso The study of caloric testing in senior patients

    Directory of Open Access Journals (Sweden)

    Débora Cristina de Oliveira Bezerra

    2008-01-01

    Full Text Available OBJETIVO: realizar o estudo da prova calórica em pacientes idosos com queixa de tontura, acompanhada ou não de zumbido com finalidade de traçar um perfil dos idosos quanto os sintomas vestibulares. MÉTODOS: fizeram parte da amostra 143 pacientes, com faixa etária variando de 60 a 90 anos de idade; todos realizaram o exame otoneurológico. Foram excluídos pacientes idosos com queixa de desequilíbrio e aqueles que apresentaram a queixa de zumbido desacompanhado da tontura. RESULTADOS: o estudo demonstrou que a normorreflexia, em valores absolutos, encontra-se entre 82,3% a 91,2% e os valores relativos são de 93%. Referente aos dados colhidos na anamnese, o que chamou a atenção, foi que do total de pacientes analisados, encontrou-se a tontura acompanhada de zumbido em 69% dos casos e o elevado uso de medicação em pacientes nesta faixa etária. CONCLUSÃO: na população estudada houve um predomínio da tontura acompanhada de zumbido. Em relação à prova calórica, o trabalho demonstrou a alta prevalência de pacientes com valores absolutos e relativos normais.PURPOSE: to accomplish the study of caloric testing in senior patients with dizziness, accompanied or not of with buzzing. METHODS: 143 patients were analyzed with age varying from 60 to 90 years; all of them did an otoneurologic evaluation. Senior patients with unbalance complaints and with buzzing unaccompanied with dizziness were excluded from this study. RESULTS: 82.3% to 91.2% of the patients obtained normoreflexia in absolute values and over 93% obtained normal results in relative values. Referring to the data obtained in the anamnesis, what got attention was 69% of dizziness accompanied with buzzing. And the high medication of the patients in this age group. CONCLUSION: there was a prevalence of dizziness accompanied with buzzing in the studied population. Concerning the caloric testing, the study demonstrated the high prevalence of patients with normal absolute and

  17. Density-functional calculations of Con+,Con, Con- (n≤5) clusters%Con+,Con,Con -(n≤5)团簇的密度泛函理论研究

    Institute of Scientific and Technical Information of China (English)

    张蓓; 陈楚; 张军

    2011-01-01

    The geometrical and electronic structures of Con+ ,Con,Con- (n≤5) clusters had been investigated using spin-polarized DFT calculations. The ground-state structures of Con+ ,Con,Con- (n≤5) clusters evoluted from one-dimension to three dimensional configurations. The total magnetic moment showed monotonic increase with size up to 5, which alternated with odd and even numbers. The interaction strengths between Con+-1(n≤5) cluster and Co atom were much more stronger. The electronic affinities (EA)and ionization potential (IP)also had been discussed in this work.%本文采用基于自旋极化的密度泛函理论系统研究了Con+,Con,Con- (n≤5)团簇的几何结构和电子结构特性.随尺寸的递增,Con,Con± (n≤5)团簇的基态几何结构由一维演变为三维的几何构型.总磁矩随尺寸的增加线性递增,并呈现奇偶交替的现象,从Con,Con±(n≤5)团簇系统中分离一个Co原子带正电的团簇体系需要的能量相对较大.本文对体系的电子亲和能(EA)以及离化势(IP)也进行了讨论.

  18. Comparative analysis of the post caloric nystagmus with two and four stimulations by means of the vectoeletronistagmography - doi:10.5020/18061230.2004.p135

    Directory of Open Access Journals (Sweden)

    Renata Parente de Almeida

    2012-01-01

    Full Text Available Vertigo is one of the most common symptoms nowadays and its diagnosis is based on the patient’s clinical history and on the otoneurological exam. This study aimed at analyzing the vestibular dysfunction diagnosis efficacy by using only cold caloric irrigation in vectoeletronistagmography. A retrospective survey of 174 vectoeletronistagmography exams from patients of the Audiology sector of Nucleo de Atenção Médica Integrada (NAMI in the University of Fortaleza was done, by comparing the results with two and four irrigations. From the analysed exams, 64 (36,78 % were symmetrical only with the single caloric irrigation (cold water and 110 (63,22 % were not. This kind of procedure is not efficient for the diagnosis, but it can be useful for screening, although a new study is necessary for validation

  19. Do nistagmo às provas calóricas com ar e com água From nystagmus to the air and water caloric tests

    Directory of Open Access Journals (Sweden)

    Anna Carolina Marques Perrella de Barros

    2012-08-01

    Full Text Available A prova calórica é uma importante ferramenta na avaliação da função labiríntica. OBJETIVO: Comparar o nistagmo pós-calórico da prova com ar a 50ºC e 24ºC com o da prova com água a 44ºC e 30ºC. Desenho científico: Estudo clínico cruzado randomizado. MATERIAL E MÉTODO: 40 indivíduos hígidos submetidos à avaliação da função vestibular incluindo a prova calórica com ar a 50ºC e 24ºC e com água a 44ºC e 30ºC. RESULTADOS: À comparação das provas com ar e com água, não houve diferença significante entre os valores da velocidade angular da componente lenta (VACL do nistagmo pós-calórico quanto à ordem de realização das estimulações, entre as orelhas e entre os valores de predomínio labiríntico e de preponderância direcional. Os valores da VACL foram maiores nas estimulações com água (p = 0,008; p The caloric test is an important tool for the assessment of labyrinthine function. OBJECTIVE: To compare the nystagmus response in the caloric tests with air at 50ºC and 24ºC and with water at 44ºC and 30ºC. Study Design: Randomized crossover clinical trial. MATERIALS AND METHODS: 40 healthy individuals were submitted to a neurotological evaluation, including caloric tests with air at 50ºC and 24ºC and water at 44ºC and 30ºC. RESULTS: Comparing the air and water caloric tests, there were no significant differences among the post-caloric nystagmus slow-phase velocity in relation to the stimulation order, between ears and between the values of unilateral weakness and directional preponderance. The slow-phase velocity values were higher with water (p = 0.008, p < 0.001, and cold stimulation produced stronger responses (p < 0.001. CONCLUSION: Comparing 50ºC and 24ºC air caloric test and 44ºC and 30ºC water caloric test, we observed similar slow-phase velocity values for both ears, higher responses in the cold temperature and in the test with water, and similar results of unilateral weakness or directional

  20. Heat losses estimation associated with the physical state of the thermal insulation of pipes vaporductos network in Cerro Prieto geothermal field; Estimacion de perdidas de calor asociadas al estado fisico del aislamiento termico de las tuberias de la red de vaporductos del campo geotermico Cerro Prieto

    Energy Technology Data Exchange (ETDEWEB)

    Ovando Castelar, Rosember; Martinez Estrella, Juan Ignacio; Garcia Gutierrez, Alfonso [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: rovando@iie.org.mx; jime@iie.org.mx; aggarcia@iie.org.mx; Canchola Felix, Ismael; Miranda Herrera, Carlos; Jacobo Galvan, Paul [Campo Geotermico de Cerro Prieto, Comision Federal de Electricidad, Mexicali, B.C. (Mexico)

    2010-11-15

    The Cerro Prieto Geothermal Field (CPGF) steam transportation network is constituted by 140 km of pipes with diameters ranging from 8 to 48 inches, which transport the steam of 165 producing wells to 13 power plants which have a total installed capacity of 720 MWe. Originally, the pipes are thermally insulated with a mineral wool or fiber glass layer and an external aluminum or iron cover. Due to the insulation material has been exposed to weather conditions during the field operation it shows nowadays different grades of wear-out, or even it is lacking in some parts of the network, causing higher heat losses from the pipes to the environment. In this work, the magnitude of the heat losses related with the present condition of the thermal insulation throughout the pipeline network is assessed. This involved determining the longitude and diameter, as well as the insulation condition of each single pipeline section, and the calculation of the heat transfer coefficients for the different thermal insulation conditions defined for this study. [Spanish] La red de transporte de vapor del campo geotermico Cerro Prieto (CGCP) esta constituida por aproximadamente 140 km de tuberias de 8 a 48 pulgadas de diametro, las cuales conducen el vapor producido por 165 pozos hacia 13 plantas generadoras, cuya capacidad instalada es de 720 MWe. Originalmente, estas tuberias son aisladas termicamente con una capa de 2 pulgadas de material aislante a base de lana mineral o fibra de vidrio, y una proteccion exterior de aluminio o hierro. Debido principalmente al impacto de las condiciones meteorologicas durante el tiempo de operacion del campo, en algunas porciones de la red el aislante presenta actualmente distintos grados de deterioro, o incluso se encuentra ausente, lo cual se traduce en una mayor perdida de calor desde las tuberias hacia el medio ambiente. En el presente trabajo se evalua la magnitud de las perdidas de calor asociadas al estado fisico del aislamiento termico de las

  1. Evaluación de un recuperador de calor en una industria frigorífica//Evaluation of waste heat recovery in frigorific industry

    Directory of Open Access Journals (Sweden)

    Josué Imbert‐González

    2014-01-01

    Full Text Available La recuperación de calor forma parte de las medidas propuestas para el empleo adecuado del amoniaco en países tropicales. Este artículo analiza un sistema de recuperación de calor instalado en una instalación de refrigeración industrial. En el análisis, que parte de las lecturas comparativas de parámetros de operación de la instalación, se determinó la efectividad del intercambio térmico, el incremento en laeficiencia del sistema de refrigeración, así como el combustible ahorrado por concepto de calentamiento del agua en la industria. Los resultados obtenidos reportaron que el diseño térmico basado en intercambio de calor en espacios anulares, permite un ahorro importante de recursos y un elevado índice de aprovechamiento térmico.Palabras claves: recuperación de calor, instalación frigorífica, ahorro de energía.________________________________________________________________________________AbstractThe waste heat recovery by heat pipes is accepted as an excellent way of saving energy and preventing global warming. This article assesses the impact of the use of a heat exchanger used as a heat recovery in the refrigeration industry. Elements are evaluated from the point of view of heat transfer, evaluating the quality of heat exchange process. Is calculated increase in the efficiency of the cooling system. The heated water is used in the steam generation system of the industry. Is calculated fuel consumption savings resulting from this warming. The findings provide elements that show the enormous potential of this technique in the refrigeration industry.Key words: waste heat recovery, Industrial refrigeration, saving energy.

  2. Reducing Liver Fat by Low Carbohydrate Caloric Restriction Targets Hepatic Glucose Production in Non-Diabetic Obese Adults with Non-Alcoholic Fatty Liver Disease

    OpenAIRE

    Haoyong Yu; Weiping Jia; ZengKui Guo

    2014-01-01

    Non-alcoholic fatty liver disease (NAFLD) impairs liver functions, the organ responsible for the regulation of endogenous glucose production and thus plays a key role in glycemic homeostasis. Therefore, interventions designed to normalize liver fat content are needed to improve glucose metabolism in patients affected by NAFLD such as obesity. Objective: this investigation is designed to determine the effects of caloric restriction on hepatic and peripheral glucose metabolism in obese humans w...

  3. Sexual dimorphism in the lasting effects of moderate caloric restriction during gestation on energy homeostasis in rats is related with fetal programming of insulin and leptin resistance

    Directory of Open Access Journals (Sweden)

    Palou Mariona

    2010-08-01

    Full Text Available Abstract Aim We aimed to characterize the lasting effect of moderate caloric restriction during early pregnancy on offspring energy homeostasis, by focusing on the effects on food intake and body weight as well as on the insulin and leptin systems. Methods Male and female offspring of 20% caloric restricted dams (from 1 to 12 days of pregnancy (CR and from control dams were studied. These animals were fed after weaning with a normal-fat (NF diet until the age of 4 months, and then moved to a high-fat (HF diet. Blood parameters were measured under fed and 14-h fasting conditions at different ages (2, 4 and 5 months. Food preferences were also assessed in adult animals. Results Accumulated caloric intake from weaning to the age of 5 months was higher in CR animals compared with their controls, and this resulted in higher body weight in adulthood in males, but not in females. Both male and female CR animals already showed higher insulin levels at the age of 2 months, under fed conditions, and higher HOMA-IR from the age of 4 months, compared with their controls. CR male animals, but not females, displayed higher preference for fat-rich food than their controls in adulthood and higher circulating leptin levels when they were under HF diet. Conclusion It is suggested that hyperinsulinemia may play a role in the etiology of hyperphagia in the offspring of caloric restricted animals during gestation, with different outcomes on body weight depending on the gender, which could be associated with different programming effects on later leptin resistance.

  4. Heat transfer study for convection and radiation in an open cavity; Estudio de de la transferencia de calor por convencion y radiacion en una cavidad abierta

    Energy Technology Data Exchange (ETDEWEB)

    Cabanillas Lopez, Rafael E [Universidad de Sonora, Hermosillo, Sonora (Mexico); Estrada Gasca, Claudio A [Centro de Investigacion en Energia-UNAM, Temixco, Morelos (Mexico); Alvarez Garcia, Gabriela S [CENIDET, Cuernavaca, Morelos (Mexico)

    2000-07-01

    Interaction of natural convection and radiation heat transfer in an open side square cavity has been simulated numerically. Previous studies have shown results of the simulation of heat transfer for convection on this geometry. This paper reports the effect of considering both the convection and the radiation mechanisms. Radiation was found to have a great influence on the total amount of heat lost by the cavity as well as on the pattern of flow and on the temperature field. Computations were performed within the domain of the cavity for two-dimensional laminar flow problem. The average of heat transfer coefficient was calculated for several values of the Grashof number for air (Pr = 0.7), with the bottom wall at 500 K (constant temperature) and the open side at 300 K. [Spanish] Se presenta el estudio de la interaccion conveccion natural-radiacion en una cavidad rectangular abierta. Algunos estudios anteriores han mostrado resultados sobre la transferencia de calor por el mecanismo de conveccion natural sobre cavidades abiertas. Aqui se presenta la influencia de considerar ambos mecanismos de transferencia de calor, la conveccion y la radiacion. Se demuestra que el intercambio radiactivo tiene una gran influencia tanto en la cantidad total de calor perdido por la cavidad al ambiente, como en el patron de flujo y de temperatura dentro de la cavidad. Se resuelven numericamente las ecuaciones gobernantes para flujo laminar en dos dimensiones y se calcula el coeficiente promedio de transferencia de calor para diferentes valores del Grashof en una cavidad llena de aire (Pr 0.7), teniendo la pared del fondo de la cavidad a 500 K y los alrededores a 300 K.

  5. Plain water consumption is associated with lower intake of caloric beverage: cross-sectional study in Mexican adults with low socioeconomic status

    OpenAIRE

    Illescas-Zarate, Daniel; Espinosa-Montero, Juan; Flores, Mario; Barquera, Simon

    2015-01-01

    Background Plain water (PW) should be the main beverage consumed by the population. However, consumption of caloric beverages (CB) has increased considerably worldwide. The purpose of this paper is to analyze the association between CB and PW intake in Mexican adults with a low socioeconomic status (SES). Methods In a cross-sectional design, beverage consumption was evaluated with a 24-h beverages recall using the five-step multiple-pass method recommended by the U.S. Department of Agricultur...

  6. El golpe de calor en la actividad física y el deporte (versión traducida al español

    Directory of Open Access Journals (Sweden)

    Yuri Hosokawa

    2014-12-01

    Full Text Available El golpe de calor por esfuerzo (GCE es una de las causas principales de muerte súbita durante el deporte y la actividad física. Solamente en el fútbol americano han ocurrido 46 muertes documentadas en los EE.UU. entre 1995 y 2010. En el 2003, la asociación responsable por los deportes universitarios de los EE.UU. estableció pautas obligatorias de aclimatización al calor, las cuales tuvieron como resultado una disminución exitosa en el número de muertes por golpe de calor en ese deporte. Sin embargo, a pesar de los avances en la atención médica moderna y una mayor conciencia sobre medidas de seguridad para el calor, la falta de atención adecuada en el sitio para los pacientes continúa contribuyendo GCE, especialmente a nivel juvenil. Está debidamente establecido en las publicaciones científicas que es posible, en gran medida, prevenir las muertes por GCE en los contextos de deportes organizados, si se brinda una educación apropiada y se dispone de personal médico entendido en el reconocimiento y tratamiento del GCE. En este documento se hace una revisión de las mejores prácticas médicas actuales y de la evidencia sobre la epidemiología, fisiopatología, factores de riesgo, reconocimiento, tratamiento, prevención y recomendaciones sobre el regreso a la práctica deportiva para el GCE, específicamente en lo pertinente al contexto del deporte organizado.

  7. Prolonged Caloric Restriction in Obese Patients With Type 2 Diabetes Mellitus Decreases Plasma CETP and Increases Apolipoprotein AI Levels Without Improving the Cholesterol Efflux Properties of HDL

    OpenAIRE

    Wang, Yanan; Snel, Marieke; Jonker, Jacqueline T; Hammer, Sebastiaan; Lamb, Hildo J.; de Roos, Albert; Meinders, A. Edo; Pijl, Hanno; Romijn, Johannes A.; Johannes W A Smit; Jazet, Ingrid M.; Rensen, Patrick C N

    2011-01-01

    OBJECTIVE Using a mouse model for human-like lipoprotein metabolism, we observed previously that reduction of the hepatic triglyceride (TG) content resulted in a decrease in plasma cholesteryl ester transfer protein (CETP) and an increase in HDL levels. The aim of the current study was to investigate the effects of prolonged caloric restriction in obese patients with type 2 diabetes mellitus, resulting in a major reduction in hepatic TG content, on plasma CETP and HDL levels. RESEARCH DESIGN ...

  8. Bruising of the esophagus as a cause of gastrointestinal bleeding in a case of heatstroke Hematomas esofágicos como causa de hemorragia digestiva en un caso de golpe de calor

    Directory of Open Access Journals (Sweden)

    A. J. Lucendo Villarín

    2005-08-01

    Full Text Available Alterations in blood clotting are a frequent complication of serious heatstroke and may result in gastrointestinal bleeding. We report the case of a 26-year-old man who was admitted to our hospital with symptoms of hyperthermia associated with encephalopathy and disseminated intravascular coagulation (DIC after prolonged exposure to sunlight. He presented hematemesis, after which he was diagnosed with having a bruising of the esophagus that took up the upper and lower thirds, there being no other lesions in the stomach or duodenum. After supportive treatment and following the resolution of the underlying pathology, the endoscopy-revealed injuries healed with a complete normalization of the esophageal mucosa. Esophageal submucosal bruising is an exceptional cause of hematemesis in serious heatstroke not previously described in the literature.Las alteraciones de la coagulación son una complicación frecuente en el golpe de calor grave, y pueden ser causa de hemorragia digestiva. Presentamos el caso de un varón de 26 años que fue admitido en nuestro hospital por un cuadro de hipertermia, asociado con encefalopatía y coagulación intravascular diseminada tras exposición solar prolongada. Presentó hematemesis por la que fue diagnosticado de múltiples hematomas esofágicos que ocupaban los tercios superior e inferior del órgano, en ausencia de otras lesiones en estómago y duodeno. Tras el tratamiento de soporte y la resolución de la patología subyacente, desaparecieron las lesiones endoscópicas, normalizándose la mucosa esofágica.

  9. Caloric restriction of db/db mice reverts hepatic steatosis and body weight with divergent hepatic metabolism.

    Science.gov (United States)

    Kim, Kyung Eun; Jung, Youngae; Min, Soonki; Nam, Miso; Heo, Rok Won; Jeon, Byeong Tak; Song, Dae Hyun; Yi, Chin-Ok; Jeong, Eun Ae; Kim, Hwajin; Kim, Jeonghyun; Jeong, Seon-Yong; Kwak, Woori; Ryu, Do Hyun; Horvath, Tamas L; Roh, Gu Seob; Hwang, Geum-Sook

    2016-01-01

    Non-alcoholic fatty liver disease (NAFLD) is one of the most frequent causes of liver disease and its prevalence is a serious and growing clinical problem. Caloric restriction (CR) is commonly recommended for improvement of obesity-related diseases such as NAFLD. However, the effects of CR on hepatic metabolism remain unknown. We investigated the effects of CR on metabolic dysfunction in the liver of obese diabetic db/db mice. We found that CR of db/db mice reverted insulin resistance, hepatic steatosis, body weight and adiposity to those of db/m mice. (1)H-NMR- and UPLC-QTOF-MS-based metabolite profiling data showed significant metabolic alterations related to lipogenesis, ketogenesis, and inflammation in db/db mice. Moreover, western blot analysis showed that lipogenesis pathway enzymes in the liver of db/db mice were reduced by CR. In addition, CR reversed ketogenesis pathway enzymes and the enhanced autophagy, mitochondrial biogenesis, collagen deposition and endoplasmic reticulum stress in db/db mice. In particular, hepatic inflammation-related proteins including lipocalin-2 in db/db mice were attenuated by CR. Hepatic metabolomic studies yielded multiple pathological mechanisms of NAFLD. Also, these findings showed that CR has a therapeutic effect by attenuating the deleterious effects of obesity and diabetes-induced multiple complications. PMID:27439777

  10. A meta-analysis of caloric restriction gene expression profiles to infer common signatures and regulatory mechanisms.

    Science.gov (United States)

    Plank, Michael; Wuttke, Daniel; van Dam, Sipko; Clarke, Susan A; de Magalhães, João Pedro

    2012-04-01

    Caloric restriction, a reduction in calorie intake without malnutrition, retards age-related degeneration and extends lifespan in several organisms. CR induces multiple changes, yet its underlying mechanisms remain poorly understood. In this work, we first performed a meta-analysis of microarray CR studies in mammals and identified genes and processes robustly altered due to CR. Our results reveal a complex array of CR-induced changes and we re-identified several genes and processes previously associated with CR, such as growth hormone signalling, lipid metabolism and immune response. Moreover, our results highlight novel associations with CR, such as retinol metabolism and copper ion detoxification, as well as hint of a strong effect of CR on circadian rhythms that in turn may contribute to metabolic changes. Analyses of our signatures by integrating co-expression data, information on genetic mutants, and transcription factor binding site analysis revealed candidate regulators of transcriptional modules in CR. Our results hint at a transcriptional module involved in sterol metabolism regulated by Srebf1. A putative regulatory role of Ppara was also identified. Overall, our conserved molecular signatures of CR provide a comprehensive picture of CR-induced changes and help understand its regulatory mechanisms.

  11. Caloric Restriction and the Nutrient-Sensing PGC-1α in Mitochondrial Homeostasis: New Perspectives in Neurodegeneration

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    Daniele Lettieri Barbato

    2012-01-01

    Full Text Available Mitochondrial activity progressively declines during ageing and in many neurodegenerative diseases. Caloric restriction (CR has been suggested as a dietary intervention that is able to postpone the detrimental aspects of aging as it ameliorates mitochondrial performance. This effect is partially due to increased mitochondrial biogenesis. The nutrient-sensing PGC-1α is a transcriptional coactivator that promotes the expression of mitochondrial genes and is induced by CR. It is believed that many of the mitochondrial and metabolic benefits of CR are due to increased PGC-1α activity. The increase of PGC-1α is also positively linked to neuroprotection and its decrement has been involved in the pathogenesis of many neurodegenerative diseases. This paper aims to summarize the current knowledge about the role of PGC-1α in neuronal homeostasis and the beneficial effects of CR on mitochondrial biogenesis and function. We also discuss how PGC-1α-governed pathways could be used as target for nutritional intervention to prevent neurodegeneration.

  12. Caloric restriction protects against electrical kindling of the amygdala by inhibiting the mTOR signaling pathway.

    Science.gov (United States)

    Phillips-Farfán, Bryan V; Rubio Osornio, María Del Carmen; Custodio Ramírez, Verónica; Paz Tres, Carlos; Carvajal Aguilera, Karla G

    2015-01-01

    Caloric restriction (CR) has been shown to possess antiepileptic properties; however its mechanism of action is poorly understood. CR might inhibit the activity of the mammalian or mechanistic target of rapamycin (mTOR) signaling cascade, which seems to participate crucially in the generation of epilepsy. Thus, we investigated the effect of CR on the mTOR pathway and whether CR modified epilepsy generation due to electrical amygdala kindling. The former was studied by analyzing the phosphorylation of adenosine monophosphate-activated protein kinase, protein kinase B and the ribosomal protein S6. The mTOR cascade is regulated by energy and by insulin levels, both of which may be changed by CR; thus we investigated if CR altered the levels of energy substrates in the blood or the level of insulin in plasma. Finally, we studied if CR modified the expression of genes that encode proteins participating in the mTOR pathway. CR increased the after-discharge threshold and tended to reduce the after-discharge duration, indicating an anti-convulsive action. CR diminished the phosphorylation of protein kinase B and ribosomal protein S6, suggesting an inhibition of the mTOR cascade. However, CR did not change glucose, β-hydroxybutyrate or insulin levels; thus the effects of CR were independent from them. Interestingly, CR also did not modify the expression of any investigated gene. The results suggest that the anti-epileptic effect of CR may be partly due to inhibition of the mTOR pathway.

  13. Caloric restriction increases internal iliac artery and penil nitric oxide synthase expression in rat: Comparison of aged and adult rats

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    Emin Ozbek

    2013-09-01

    Full Text Available Because of the positive corelation between healthy cardiovascular system and sexual life we aimed to evaluate the effect of caloric restriction (CR on endothelial and neuronal nitric oxide synthase (eNOS, nNOS expression in cavernousal tissues and eNOS expression in the internal iliac artery in young and aged rats. Young (3 mo, n = 7 and aged (24 mo, n = 7 male Sprague-Dawley rats were subjected to 40% CR and were allowed free access to water for 3 months. Control rats (n = 14 fed ad libitum had free access to food and water at all times. On day 90, rats were sacrified and internal iliac arteries and penis were removed and parafinized, eNOS and nNOS expression evaluated with immunohistochemistry. Results were evaluated semiquantitatively. eNOS and nNOS expression in cavernousal tis- sue in CR rats were more strong than in control group in both young and old rats. eNOS expression was also higher in the internal iliac arteries of CR rats than in control in young and old rats. As a result of our study we can say that there is a positive link between CR and neurotransmitter of erection in cavernousal tissues and internal iliac arteries. CR has beneficial effect to prevent sexual dysfunction in young and old animals and possible humans.

  14. El comportamiento térmico de la ciudad de Las Palmas de G. C.: La Isla de calor nocturna

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    Lidia Esther Romero Martín

    2013-10-01

    Full Text Available En este trabajo se presentan las principales pautas del comportamiento térmico de la ciudad de Las Palmas de Gran Canaria. Utilizando el método de los recorridos urbanos, durante un año se registraron los datos de temperatura y humedad de 42 puntos de la ciudad, que incluyen áreas formales y funcionales diferentes. Los resultados confirman la existencia de una isla de calor nocturna de carácter bifocal y de intensidad moderada, aunque puede llegar a alcanzar valores de 5.3º C. Su localización está controlada fundamentalmente por la densidad edificatoria y la intensidad del tráfico. El Istmo de la Isleta se comporta como una isla de frescor.In this article, we present the outlines of the thermal behaviour of the city of Las Palmas de Gran Canaria. Using the method of travelling around the city, we recorded temperature and humidity data for 42 sites in the city, including different formal and functional areas. The results confirm that there is a bi-focal and moderate island of nocturnal heat, although it can reach 5.3ºC. This is determined fundamentally by building density and the intensity of the traffic. The Isthmus of La Isleta acts as an island of fresh temperatures.

  15. Obesity-Induced Colorectal Cancer Is Driven by Caloric Silencing of the Guanylin-GUCY2C Paracrine Signaling Axis.

    Science.gov (United States)

    Lin, Jieru E; Colon-Gonzalez, Francheska; Blomain, Erik; Kim, Gilbert W; Aing, Amanda; Stoecker, Brian; Rock, Justin; Snook, Adam E; Zhan, Tingting; Hyslop, Terry M; Tomczak, Michal; Blumberg, Richard S; Waldman, Scott A

    2016-01-15

    Obesity is a well-known risk factor for colorectal cancer but precisely how it influences risks of malignancy remains unclear. During colon cancer development in humans or animals, attenuation of the colonic cell surface receptor guanylyl cyclase C (GUCY2C) that occurs due to loss of its paracrine hormone ligand guanylin contributes universally to malignant progression. In this study, we explored a link between obesity and GUCY2C silencing in colorectal cancer. Using genetically engineered mice on different diets, we found that diet-induced obesity caused a loss of guanylin expression in the colon with subsequent GUCY2C silencing, epithelial dysfunction, and tumorigenesis. Mechanistic investigations revealed that obesity reversibly silenced guanylin expression through calorie-dependent induction of endoplasmic reticulum stress and the unfolded protein response in intestinal epithelial cells. In transgenic mice, enforcing specific expression of guanylin in intestinal epithelial cells restored GUCY2C signaling, eliminating intestinal tumors associated with a high calorie diet. Our findings show how caloric suppression of the guanylin-GUCY2C signaling axis links obesity to negation of a universal tumor suppressor pathway in colorectal cancer, suggesting an opportunity to prevent colorectal cancer in obese patients through hormone replacement with the FDA-approved oral GUCY2C ligand linaclotide. PMID:26773096

  16. Large reversible caloric effect in FeRh thin films via a dual-stimulus multicaloric cycle

    Science.gov (United States)

    Liu, Yang; Phillips, Lee C.; Mattana, Richard; Bibes, Manuel; Barthélémy, Agnès; Dkhil, Brahim

    2016-05-01

    Giant magnetocaloric materials are promising for solid-state refrigeration, as an alternative to hazardous gases used in conventional cooling devices. A giant magnetocaloric effect was discovered near room temperature in near-equiatomic FeRh alloys some years before the benchmark study in Gd5Si2Ge2 that launched the field. However, FeRh has attracted significantly less interest in cooling applications mainly due to irreversibility in magnetocaloric cycles associated with the large hysteresis of its first-order metamagnetic phase transition. Here we overcome the irreversibility via a dual-stimulus magnetic-electric refrigeration cycle in FeRh thin films via coupling to a ferroelectric BaTiO3 substrate. This experimental realization of a multicaloric cycle yields larger reversible caloric effects than either stimulus alone. While magnetic hysteretic losses appear to be reduced by 96% in dual-stimulus loops, we show that the losses are simply transferred into an elastic cycle, contrary to common belief. Nevertheless, we show that these losses do not necessarily prohibit integration of FeRh in practical refrigeration systems. Our demonstration of a multicaloric refrigeration cycle suggests numerous designs for efficient solid-state cooling applications.

  17. Reversibility of β-Cell-Specific Transcript Factors Expression by Long-Term Caloric Restriction in db/db Mouse

    Directory of Open Access Journals (Sweden)

    Chunjun Sheng

    2016-01-01

    Full Text Available Type 2 diabetes (T2D is characterized by β-cell dedifferentiation, but underlying mechanisms remain unclear. The purpose of the current study was to explore the mechanisms of β-cell dedifferentiation with and without long-term control of calorie intake. We used a diabetes mouse model (db/db to analyze the changes in the expression levels of β-cell-specific transcription factors (TFs and functional factors with long-term caloric restriction (CR. Our results showed that chronic euglycemia was maintained in the db/db mice with long-term CR intervention, and β-cell dedifferentiation was significantly reduced. The expression of Glut2, Pdx1, and Nkx6.1 was reversed, while MafA expression was significantly increased with long-term CR. GLP-1 pathway was reactivated with long-term CR. Our work showed that the course of β-cell dedifferentiation can intervene by long-term control of calorie intake. Key β-cell-specific TFs and functional factors play important roles in maintaining β-cell differentiation. Targeting these factors could optimize T2D therapies.

  18. Beverage Consumption Patterns and Micronutrient and Caloric Intake from Beverages in Older Adults with Mild Cognitive Impairment.

    Science.gov (United States)

    Venci, Brittany; Hodac, Nicole; Lee, Seung-Yeon; Shidler, Marcelle; Krikorian, Robert

    2015-01-01

    The purpose of this study was to determine total water intake and patterns of beverage consumption, and its contribution to total daily micronutrients and calories in older adults with mild memory decline. A descriptive, cross-sectional study was used with 60 independent community-dwelling older adults (71.7 ± 5.4 years) with mild cognitive impairment, who were mostly female, well-educated, and white. Three-day food records were analyzed using the Nutrition Data Systems for Research. Descriptive statistics were conducted for a summary of demographics, the average intakes of beverages, and the contribution of beverages to total calorie and micronutrient intakes. Total daily water intake was 53.6 ± 26.7 fl oz and milk, plain water, and tea/coffee were beverages consumed most frequently. Beverage consumption contributed substantially to the intake of vitamin D (29.4%), calcium (26.4%), riboflavin (22.0%), magnesium (18.9%), and vitamin C (18.1%), but constituted only ∼12.5% of total energy. These findings suggest that nutrient-dense beverages play a fundamental role in overall micronutrient intake, despite comprising a small component of daily caloric intake. Incorporating adequate amounts of such beverages in meals and snacks may help older adults meet their nutrient recommendations. PMID:26571357

  19. Reducing Liver Fat by Low Carbohydrate Caloric Restriction Targets Hepatic Glucose Production in Non-Diabetic Obese Adults with Non-Alcoholic Fatty Liver Disease

    Directory of Open Access Journals (Sweden)

    Haoyong Yu

    2014-09-01

    Full Text Available Non-alcoholic fatty liver disease (NAFLD impairs liver functions, the organ responsible for the regulation of endogenous glucose production and thus plays a key role in glycemic homeostasis. Therefore, interventions designed to normalize liver fat content are needed to improve glucose metabolism in patients affected by NAFLD such as obesity. Objective: this investigation is designed to determine the effects of caloric restriction on hepatic and peripheral glucose metabolism in obese humans with NAFLD. Methods: eight non-diabetic obese adults were restricted for daily energy intake (800 kcal and low carbohydrate (<10% for 8 weeks. Body compositions, liver fat and hepatic glucose production (HGP and peripheral glucose disposal before and after the intervention were determined. Results: the caloric restriction reduced liver fat content by 2/3 (p = 0.004. Abdominal subcutaneous and visceral fat, body weight, BMI, waist circumference and fasting plasma triglyceride and free fatty acid concentrations all significantly decreased (p < 0.05. The suppression of post-load HGP was improved by 22% (p = 0.002 whereas glucose disposal was not affected (p = 0.3. Fasting glucose remained unchanged and the changes in the 2-hour plasma glucose and insulin concentration were modest and statistically insignificant (p > 0.05. Liver fat is the only independent variable highly correlated to HGP after the removal of confounders. Conclusion: NAFLD impairs HGP but not peripheral glucose disposal; low carbohydrate caloric restriction effectively lowers liver fat which appears to directly correct the HGP impairment.

  20. Caloric restriction induces energy-sparing alterations in skeletal muscle contraction, fiber composition and local thyroid hormone metabolism that persist during catch-up fat upon refeeding

    Directory of Open Access Journals (Sweden)

    Paula Bresciani M. De Andrade

    2015-09-01

    Full Text Available Weight regain after caloric restriction results in accelerated fat storage in adipose tissue. This catch-up fat phenomenon is postulated to result partly from suppressed skeletal muscle thermogenesis, but the underlying mechanisms are elusive. We investigated whether the reduced rate of skeletal muscle contraction-relaxation cycle that occurs after caloric restriction persists during weight recovery and could contribute to catch-up fat. Using a rat model of semistarvation-refeeding, in which fat recovery is driven by suppressed thermogenesis, we show that contraction and relaxation of leg muscles are slower after both semistarvation and refeeding. These effects are associated with (i higher expression of muscle deiodinase type 3 (DIO3 which inactivates tri-iodothyronine (T3, and lower expression of T3-activating enzyme, deiodinase type 2 (DIO2, (ii slower net formation of T3 from its T4 precursor in muscles, and (iii accumulation of slow fibers at the expense of fast fibers. These semistarvation-induced changes persisted during recovery and correlated with impaired expression of transcription factors involved in slow-twitch muscle development.We conclude that diminished muscle thermogenesis following caloric restriction results from reduced muscle T3 levels, alteration in muscle-specific transcription factors, and fast-to-slow fiber shift causing slower contractility. Energy-sparing effects persist during weight recovery and likely contribute to catch-up fat.

  1. Age-related decrease in aromatase and estrogen receptor(ERαand ERβ) expression in rat testes: protective effect of low caloric diets

    Institute of Scientific and Technical Information of China (English)

    Khaled Hamden; Dorothee Silandre; Christelle Delalande; Abdefattah El Feki; Serge Carreau

    2008-01-01

    Aim: To examine the effects on rat aging of caloric restriction (CR1) and undernutrition (CR2) on the body and on testicular weights, on two enzymatic antioxidants (superoxide dismutase and catalase), on lipid peroxidation and on the expression of testicular aromatase and estrogen receptors (ER). Methods: CR was initiated in 1-month-old rats and carried on until the age of 18 months. Results: In control and CR2 rats an age-related decrease of the aromatase and of ER (α and β) gene expression was observed; in parallel a diminution of testicular weights, and of the total number and motility of epididymal spermatozo was recorded. In addition, aging in control and CR2 rats was accom-panied by a significant decrease in testicular superoxide dismutase, catalase activities, and an increase in lipid peroxidation level (thiobarbituric acid reactive substance), associated with alterations of spermatogenesis. Conversely, caloric restriction-treatment exerted a protective effect and all the parameters were less affected by aging. Conclusion:These results indicate that during aging, a low caloric diet (not undernutrition) is beneficial for spermatogenesis and likely improves the protection of the cells via an increase of the cellular antioxidant defense system in which aromatase/ER could play a role.

  2. Efecto de la suplementación con grasas protegidas sobre parámetros productivos y reproductivos en vacas lactantes

    Directory of Open Access Journals (Sweden)

    Mónica Duque Q.

    2013-11-01

    Full Text Available Objetivo. Investigar el efecto de la suplementación con jabones cálcicos protegidos, conteniendo ácidos grasos omega 3 ó 6 sobre la producción, composición de la leche y desempeño reproductivo. Materiales y métodos. Se utilizaron 24 vacas en un diseño mixto desde 20 días antes de la fecha prevista del parto hasta 105 días postparto, asignadas a los diferentes tratamientos; C: dieta control, O6: animales suplementados con grasas protegidas conteniendo omega 6 y O3: animales suplementados con grasas protegidas conteniendo omega 3. Se determinó la producción y la composición de la leche, así como la condición corporal (CC, el primer calor y primera ovulación posparto. Resultados. La suplementación con omega 3 ó 6 no afectó la producción láctea, ni los porcentajes de grasa, proteína, sólidos no grasos (SNG y sólidos totales (ST. Sin embargo, hubo un efecto positivo a los 45 días posparto sobre la CC cuando los animales fueron suplementados con omega 6 (p<0.05 lo que se reflejó en una recuperación ovárica posparto más rápida (42.24±16.75 días a la primera ovulación posparto. Conclusiones. La utilización de la suplementación con omega 6 mejoró la condición corporal de los animales en el posparto temprano, disminuyendo los días a la primera ovulación y primer calor posparto, sin afectar la producción ni composición de la leche. La suplementación con omega 3 no influyó en ningún parámetro productivo en el posparto temprano.

  3. Diffusion and dispersion heat of hydrotermal discharge from power plant; Difusion y dispersion de calor de la descarga hidrotermal de una central termoelectrica

    Energy Technology Data Exchange (ETDEWEB)

    Rendon Villalobos, J. Rodolfo

    1996-12-31

    numerica del comportamiento hidrodinamico de la descarga al mar del agua de enfriamiento de la central termoelectrica Tuxpan (CTT) bajo dos distintas condiciones ambientales meteorologicas y oceanograficas, a saber: Caso I, viento variable de direccion SW con intensidad promedio igual a 3 m s-1 y Caso II, viento variable del NW con intensidad promedio igual a 11.10 m s-1. Las simulaciones numericas se realizaron mediante un modelo tridimensional de circulacion costera y difusion y dispersion de calor. El analisis estadistico del banco de datos de intensidad y direccion del viento medido del 1 de enero de 1981 al 31 de diciembre de 1983, indica que el numero de valores de mayor ocurrencia se presento dentro del intervalo de 180 grados a 315 grados. Por lo mismo, el efecto del viento proveniente del sector sur genera un patron de circulacion superficial de flujo norte que alejan de la obra de toma el agua caliente descargada. En contraste, el viento que proviene del sector norte genera corrientes superficiales de flujo sur que impulsa el efluente hidrotermico hacia la obra de toma. Las comparaciones entre los resultados de las simulaciones numericas y los datos de campo indican que, para una variedad de condiciones ambientales meteorologicas y oceanograficas representativas del Sitio Tuxpan (ST), el modelo simula correctamente los patrones de difusion y dispersion superficial de los efluentes medidos los dias 19, 20 y 21 de agosto de 1992 (Caso I) y 26 de noviembre de 1992 (Caso II). La precision promedio con la cual el modelo predice las areas de impacto de los efluentes descargados en el ST es de {+-} 11%. Para todos los casos analizados, el tamano real del area de impacto termico que podria alterar substancialmente el ecosistema marino no fue mayor a 0.1 Km{sup 2}. Los posibles efectos ecologicos que podrian resultar como consecuencia de los gradientes termicos inducidos por la descarga superficial de agua caliente solo podrian ser considerados de significancia local. Los

  4. RASGOS DE PERSONALIDAD EN PACIENTES CON OBESIDAD

    Directory of Open Access Journals (Sweden)

    Alejandra Bravo Del Toro

    2011-01-01

    Full Text Available El presente estudio analizó los rasgos de personalidad con mayor incidencia en una población mexicana con obesidad. Se distinguieron los rasgos que intervienen en el funcionamiento diario de los sujetos. La muestra estuvo conformada por 60 pacientes: 31 hombres y 29 mujeres, con edades de 30 a 40 años, casados, con nivel educativo básico y que acudían a consulta médica en un centro de diagnóstico clínico, con antecedentes de obesidad. Se utilizó el perfil-inventario de la personalidad de Gordon, según el cual se comprobó que los pacientes con obesidad tienden a mostrar rasgos de personalidad por debajo de la norma. Los análisis demostraron relaciones significativas entre la gente obesa y cada uno de los rasgos de personalidad con menor prevalencia que mide la escala.

  5. Tratamiento del paciente con artrosis

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    Francisco Vargas Negrín

    2014-01-01

    Full Text Available El manejo terapéutico del paciente con artrosis tiene como objetivo disminuir la sintomatología dolorosa e inflamatoria, mejorar la capacidad funcional del paciente y la aplicación de intervenciones terapéuticas eficaces y lo más seguras posibles. Un enfoque centrado en el paciente implica su participación activa en el diseño del plan terapéutico y en la toma de decisiones informadas oportunas en todas las etapas de la enfermedad. La educación terapéutica, la actividad física y el ejercicio terapéutico junto con el control de peso, en caso de sobrepeso u obesidad, constituyen el núcleo central del tratamiento. Los autocuidados individuales y por los familiares son fundamentales en el control del día a día del paciente. El uso de terapias físicas, ayudas técnicas (bastón, etc. y de fármacos tipo analgésicos simples, opioides y antiinflamatorios tiene evidencias demostradas en el control del dolor, mejora la funcionalidad y la calidad de vida del paciente y una clara recomendación de uso en el tratamiento de la artrosis. La cirugía conservadora y la de reemplazo articular se indican en los casos en los que no se logran los objetivos terapéuticos en casos concretos.

  6. Reducción del Tiempo de Ciclo de Inyección de Termoplásticos con el uso de Moldes con Tratamiento Superficial por Nitruración Cycle Time Reduction of Thermoplastic Injection using Nitriding Treatment Surface Molds

    Directory of Open Access Journals (Sweden)

    Emerson J Corazza

    2012-01-01

    Full Text Available Se presenta un estudio sobre la transferencia de calor en un molde, comparando los ensayos de inyección utilizando moldes con y sin tratamiento superficial de nitruración. Simulaciones del proceso se realizaron con el uso de Asistencia Computacional a Ingeniería (CAE para determinar los parámetros iniciales que se aplicaron en los ensayos reales en moldes instrumentados de acero P20 (con y sin tratamientos, inyectados con el polímero poliestireno cristal. Los resultados indicaron una reducción del tiempo de enfriamiento y del tiempo de proceso en el molde con el tratamiento, debido a una mejora en la conductividad térmica.A study on the heat transfer in a mold, comparing experimental injection tests using a mold with and without surface treatment (nitriding is presented. Process simulations were carried out using Computer Aided Engineering tools (CAE for the estimation of the initial parameters to be applied in the tests in instrumented P20 steel injection molds with the polymer crystal polystyrene. Results indicated a reduction of cooling time and of the time of the process in the mold with treatment, due to an increase of the thermal conductivity.

  7. Microencapsulación con alginato en alimentos. Técnicas y aplicaciones

    Directory of Open Access Journals (Sweden)

    Bryshila Lupo Pasin

    2012-01-01

    Full Text Available El objetivo de este trabajo fue realizar una revisión de las técnicas de microencapsulación con alginato para aplicaciones en alimentos. El alginato ha sido uno de los polímeros más empleado en la microencapsulación, este forma una matriz altamente versátil, biocompatible y no tóxica para la protección de componentes activos, células o microorganismos sensibles al calor, pH, oxígeno y luz, entre otros factores, a los que son expuestos los alimentos durante el procesamiento y almacenaje. El proceso de microencapsulación con alginato se lleva a cabo a través de dos mecanismos de gelificación iónica: la gelificación externa y la gelificación interna, dependiendo de si el calcio se suministra desde fuera de las cápsulas o en el interior de las mismas. Para la preparación de microcápsulas de alginato de calcio con aplicaciones alimentarias, se tienen las técnicas por extrusión, en emulsión y secado por atomización. Aunque el secado por atomización ha sido para la industria un proceso práctico y económico, su aplicación con alginato se ha visto limitada por la viscosidad y velocidad de gelificación. Por el contrario, la técnica por extrusión ha sido la técnica tradicional empleada en las últimas décadas, debido a la uniformidad de las microcápsulas en su forma y tamaño. En este sentido, la técnica en emulsión es la aplicada más recientemente, la cual ha demostrado ser sencilla y de producción a gran escala. En la actualidad se desarrollan nuevas tecnologías a fin de disminuir el tamaño de las microcápsulas para así ampliar sus usos en la industria. Entre las últimas tendencias de microencapsulación, se estudian sistemas mixtos de matrices poliméricas con la finalidad de obtener propiedades físico-químicas combinadas, permitiendo hacer el proceso de encapsulación más eficiente tanto para la protección como para la liberación controlada del principio activo.

  8. Microencapsulación con alginato en alimentos. Técnicas y aplicaciones

    Directory of Open Access Journals (Sweden)

    Bryshila Lupo Pasin

    2012-06-01

    Full Text Available El objetivo de este trabajo fue realizar una revisión de las técnicas de microencapsulación con alginato para aplicaciones en alimentos. El alginato ha sido uno de los polímeros más empleado en la microencapsulación, este forma una matriz altamente versátil, biocompatible y no tóxica para la protección de componentes activos, células o microorganismos sensibles al calor, pH, oxígeno y luz, entre otros factores, a los que son expuestos los alimentos durante el procesamiento y almacenaje. El proceso de microencapsulación con alginato se lleva a cabo a través de dos mecanismos de gelificación iónica: la gelificación externa y la gelificación interna, dependiendo de si el calcio se suministra desde fuera de las cápsulas o en el interior de las mismas. Para la preparación de microcápsulas de alginato de calcio con aplicaciones alimentarias, se tienen las técnicas por extrusión, en emulsión y secado por atomización. Aunque el secado por atomización ha sido para la industria un proceso práctico y económico, su aplicación con alginato se ha visto limitada por la viscosidad y velocidad de gelificación. Por el contrario, la técnica por extrusión ha sido la técnica tradicional empleada en las últimas décadas, debido a la uniformidad de las microcápsulas en su forma y tamaño. En este sentido, la técnica en emulsión es la aplicada más recientemente, la cual ha demostrado ser sencilla y de producción a gran escala. En la actualidad se desarrollan nuevas tecnologías a fin de disminuir el tamaño de las microcápsulas para así ampliar sus usos en la industria. Entre las últimas tendencias de microencapsulación, se estudian sistemas mixtos de matrices poliméricas con la finalidad de obtener propiedades físico-químicas combinadas, permitiendo hacer el proceso de encapsulación más eficiente tanto para la protección como para la liberación controlada del principio activo.

  9. Un tema con muchas variaciones

    Directory of Open Access Journals (Sweden)

    Bárbara Kepowics Malinowska

    2003-01-01

    Full Text Available Se aborda el tema de ética y valores como uno de los ejes principales de la formación de la identidad de los futuros profesionistas. Se presentan los resultados de una investigación realizada con metodología cualitativa, para conocer la relación entre los valores explícitos en el proyecto universitario y los valores en los estudiantes al culminar su carrera en la Universidad. Entre las principales conclusiones, cabe destacar la heterogeneidad de los valores vividos a través de las prácticas curriculares, una discrepancia significativa entre ellos y los valores declarados en los proyectos y, por consecuencia, una diferencia entre los valores deseables y los asumidos como compromiso personal. Predomina la ética de la conveniencia y hay poca conciencia de la profesión, entendida como un servicio de calidad para la sociedad.

  10. Fare astronomia con piccoli telescopi

    CERN Document Server

    Gainer, Michael K

    2007-01-01

    Non sono necessariamente richiesti strumenti mastodontici per produrre risultati scientificamente validi nel campo dell’astronomia. Anche l’astrofilo dotato di un piccolo telescopio, con un diametro di soli 8-9 cm, può contribuire alla scienza del cielo realizzando utili osservazioni del Sole, della Luna, dei pianeti, delle comete, degli asteroidi, delle stelle doppie o variabili, delle nebulose e degli ammassi stellari. Il manuale di M.K. Gainer spiega quale sia la dotazione minima (un piccolo telescopio, un computer, una semplice fotocamera digitale), come utilizzarla, e quali siano le tecniche appropriate da adottare nelle osservazioni. Offre inoltre schemi per interpretare e ridurre i dati raccolti, nonché schede da compilare e da spedire ai centri di raccolta internazionali. Questo libro è il passaporto grazie al quale l’astrofilo può entrare a pieno titolo nel mondo affascinante della scienza astronomica.

  11. Uso y verificación con indicadores biológicos en esterilizadores de cirujanos dentistas de San Luis Potosí, México

    Directory of Open Access Journals (Sweden)

    Patiño-Marín Nuria

    2001-01-01

    Full Text Available Objetivo. Conocer el uso y verificar los ciclos de esterilización con indicadores biológicos en los equipos utilizados por cirujanos dentistas de la Facultad de Estomatología de la Universidad Autónoma de San Luis Potosí (UASLP y del Colegio Dental Potosino. Material y métodos. Estudio transversal hecho en 1999-2000. El 65% (n=130 de los odontólogos participaron con un esterilizador, la verificación se realizó por indicadores que contenían esporas de Bacillus subtilis y de Bacillus stearothermophilus. Resultados. Participaron 30 autoclaves y 100 esterilizadores de calor seco, 23 de ellos (17.7% presentaron crecimiento bacteriano; el 16.1% (n=21 de los participantes utilizan los indicadores biológicos como verificador. Los dos métodos de esterilización presentaron crecimiento bacteriano con frecuencias similares (p=>0.66. Conclusiones. Pocos cirujanos dentistas verifican su esterilizador con indicadores biológicos en los equipos que presentaron crecimiento bacteriano, sus fallas se encontraron en el proceso de esterilización. El texto completo en inglés de este artículo está disponible en: http://www.insp.mx/salud/index.html

  12. La atención a los padres con hijos con necesidades educativas especiales (NEE

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    Claudia María Pernas Pico

    2011-01-01

    Full Text Available Los padres que tienen hijos con necesidades educativas especiales (NEE necesitan al igual que sus hijos de la intervención del maestro de Audición y Lenguaje con el objetivo primordial de mejorar la comunicación y el lenguaje de los niños. Se pretende en este artículo dar un abanico de posibilidades de cómo se puede intervenir con los padres desde las escuelas: con largas horas de reuniones, con formación, con talleres, con actividades y juegos, con libretas viajeras, con pequeñas pautas, etc... Siempre desde la empatía y la profesionalidad que debe transmitir el maestro de Audición y Lenguaje. Cambiando la preocupación de los padres por su ocupación.

  13. Effects of Intermittent Fasting, Caloric Restriction, and Ramadan Intermittent Fasting on Cognitive Performance at Rest and During Exercise in Adults.

    Science.gov (United States)

    Cherif, Anissa; Roelands, Bart; Meeusen, Romain; Chamari, Karim

    2016-01-01

    The aim of this review was to highlight the potent effects of intermittent fasting on the cognitive performance of athletes at rest and during exercise. Exercise interacts with dietary factors and has a positive effect on brain functioning. Furthermore, physical activity and exercise can favorably influence brain plasticity. Mounting evidence indicates that exercise, in combination with diet, affects the management of energy metabolism and synaptic plasticity by affecting molecular mechanisms through brain-derived neurotrophic factor, an essential neurotrophin that acts at the interface of metabolism and plasticity. The literature has also shown that certain aspects of physical performance and mental health, such as coping and decision-making strategies, can be negatively affected by daylight fasting. However, there are several types of intermittent fasting. These include caloric restriction, which is distinct from fasting and allows subjects to drink water ad libitum while consuming a very low-calorie food intake. Another type is Ramadan intermittent fasting, which is a religious practice of Islam, where healthy adult Muslims do not eat or drink during daylight hours for 1 month. Other religious practices in Islam (Sunna) also encourage Muslims to practice intermittent fasting outside the month of Ramadan. Several cross-sectional and longitudinal studies have shown that intermittent fasting has crucial effects on physical and intellectual performance by affecting various aspects of bodily physiology and biochemistry that could be important for athletic success. Moreover, recent findings revealed that immunological variables are also involved in cognitive functioning and that intermittent fasting might impact the relationship between cytokine expression in the brain and cognitive deficits, including memory deficits. PMID:26438184

  14. Caloric restriction alters the metabolic response to a mixed-meal: results from a randomized, controlled trial.

    Directory of Open Access Journals (Sweden)

    Kim M Huffman

    Full Text Available OBJECTIVES: To determine if caloric restriction (CR would cause changes in plasma metabolic intermediates in response to a mixed meal, suggestive of changes in the capacity to adapt fuel oxidation to fuel availability or metabolic flexibility, and to determine how any such changes relate to insulin sensitivity (S(I. METHODS: Forty-six volunteers were randomized to a weight maintenance diet (Control, 25% CR, or 12.5% CR plus 12.5% energy deficit from structured aerobic exercise (CR+EX, or a liquid calorie diet (890 kcal/d until 15% reduction in body weightfor six months. Fasting and postprandial plasma samples were obtained at baseline, three, and six months. A targeted mass spectrometry-based platform was used to measure concentrations of individual free fatty acids (FFA, amino acids (AA, and acylcarnitines (AC. S(I was measured with an intravenous glucose tolerance test. RESULTS: Over three and six months, there were significantly larger differences in fasting-to-postprandial (FPP concentrations of medium and long chain AC (byproducts of FA oxidation in the CR relative to Control and a tendency for the same in CR+EX (CR-3 month P = 0.02; CR-6 month P = 0.002; CR+EX-3 month P = 0.09; CR+EX-6 month P = 0.08. After three months of CR, there was a trend towards a larger difference in FPP FFA concentrations (P = 0.07; CR-3 month P = 0.08. Time-varying differences in FPP concentrations of AC and AA were independently related to time-varying S(I (P<0.05 for both. CONCLUSIONS: Based on changes in intermediates of FA oxidation following a food challenge, CR imparted improvements in metabolic flexibility that correlated with improvements in S(I. TRIAL REGISTRATION: ClinicalTrials.gov NCT00099151.

  15. The effect of aging and caloric restriction on murine CD8+ T cell chemokine receptor gene expression

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    Mo RuRan

    2007-11-01

    Full Text Available Abstract Background The mechanism explaining the increased disease susceptibility in aging is not well understood. CD8+ T cells are crucial in anti-viral and anti-tumor responses. Although the chemokine system plays a critical role in CD8+ T cell function, very little is known about the relationship between aging and the T cell chemokine system. Results In this study we have examined the effect of aging on murine CD8+ T cell chemokine receptor gene expression. Freshly isolated splenic CD8+ T cells from old C57BL/6 mice were found to have higher CCR1, CCR2, CCR4, CCR5 and CXCR5, and lower CCR7 gene expression compared to their younger cohort. Anti-CD3/anti-CD28 stimulation elicited a similar robust chemokine receptor response from young and old CD8+ T cells. Western blot analyses confirmed elevated protein level of CCR4 and CCR5 in aged CD8+ T cells. Increases in T cell CCR1 and CCR5 expression also correlate to increased in vitro chemotaxis response to macrophage-inflammatory protein-1 α(MIP-1α. Finally, caloric restriction selectively prevents the loss of CD8+ T cell CCR7 gene expression in aging to the level that is seen in young CD8+ T cells. Conclusion These findings are consistent with the notion that aging exists in a state of low grade pro-inflammatory environment. In addition, our results provide a potential mechanism for the reported aging-associated impaired T cell lymphoid homing and allograft response, and reduced survival in sepsis.

  16. 限食疗法与体重控制%Caloric restriction and control of body weight

    Institute of Scientific and Technical Information of China (English)

    陈国芳; 刘超

    2014-01-01

    控制体重一直是热门话题,减重所带来的血糖、血脂、血压、胰岛素敏感性等多方面的获益,奠定了其在防治肥胖、2型糖尿病等代谢性疾病中的不可撼动的地位.获得减重的途径主要有饮食调整、运动干预、药物治疗或外科手术,本文主要讨论限食减重的问题,包括限食的减重程度,限食后的体重维持,影响减重的因素以及特殊人群的减重问题.%Control of body weight is a hot topic.It is considered as the cornerstone for the management of patients with obesity and type 2 diabetes based on the effect of improving blood glucose,lipid profile,blood pressure,and insulin sensitivity.The strategies for weight loss include diet restriction,exercise,medicine,and bariatric surgery.In the present article the relationship between caloric restriction and weight loss was reviewed,focusing on the hot topics as to what extent weight loss could be achieved,the maintenance of ideal body weight,the risk factor of weight regain,and weight loss in particulas populations like obese children,adolescents,and older adults.

  17. Development of formula diet of different caloric intake for control of blood sugar in type-2 diabetes mellitus

    International Nuclear Information System (INIS)

    During this one year randomized study dietary therapy was conducted to develop a formula diet and was compiled by 70 % of subjects. The primary aim of this Study was to maintain blood glucose as near to normal as possible. Diabetes is essentially caused by over consumption particularly carbohydrates and lack of exercise. Therefore, the key to managing it is changing these behaviors. It is critical to balance your diet with about 40% carbohydrates, 30% protein and 30% high quality healthy fats and consume unrefined, low glycemic index, complex carbohydrates. To make dietary regimen easy and convenient for our patients who were mostly illiterate or with moderate education. This project was undertaken for the development of dietary formula of different caloric intake in Pakistani population. Fifty type-2 diabetic and non obese (males and females) with maximum five year duration of the disease and age range between 30- 50 years were selected as study group while 30 control subjects without diabetes were also selected. Each individual screened for fasting blood glucose serum cholesterol, triglyceride, HDL-Cholesterol and LDL-Cholesterol at the start and follow up of the study. HbA1c only measured during follow up period. In this study blood glucose reduced from 278.70+- 33.4 mg/dl to 194.5+-28.0 mg/dl P<0.001, serum cholesterol reduced from 204.30+-46.50 mg/dl to 180.0+-36.0 mg/dl (P<0.01) and LDL--Cholesterol from 124.70+-29.10 mg/dl to 110.0 +- 35.7 mg/dl during follow up period of six months. HbA1c changed from 11.5 % to 8.4 %. Adherence to the formula diet plan thus played an important role in reducing blood glucose levels in type-2 diabetic patients. (author)

  18. Estudo da Ilha de Calor na Região Metropolitana do Rio de Janeiro Usando Dados do MODIS

    Directory of Open Access Journals (Sweden)

    Caio Atila Pereira Sena

    2014-07-01

    Full Text Available A Região Metropolitana do Rio de Janeiro (RMRJ apresenta uma série de problemas ambientais, dentre eles, a ocorrência de Ilhas de Calor Urbanas (ICU e este trabalho tem como objetivo examinar as características da ICU na RMRJ. Para tal, foram usadas composições de 8 dias de dados de Temperatura Superficial Continental (TSC geradas pelo sensor MODIS (Moderate-resolution Imaging Spectroradiometer a bordo dos satélites Aqua e Terra no período de janeiro de 2003 a dezembro de 2010. A análise foi feita agrupando-se os dados para as diferentes estações do ano e posteriormente calculando-se a média de TSC para cada estação com o intuito de verificar a variação sazonal da ICU. Observou-se que, algumas zonas apresentaram temperaturas próximas dos 50°C durante a primavera e o verão. Ao longo do outono e do inverno as médias atingiram 40°C sobre a maior parte da região de estudo. Foram registradas amplitudes térmicas de até 25°C entre áreas com diferentes níveis de urbanização, durante a primavera. No verão a amplitude foi de 20°C entre as mesmas áreas. No outono a diferença foi de 15°C e no inverno, de 10°C.

  19. Novel Approach of Using Nutraceutic-Directed Caloric Antioxidant Density and Ion-Ratio for Evaluating Fruit's Health Quality.

    Science.gov (United States)

    Hsieh, Chiu-Lan; Huang, Shang-Ming; Chen, Li-I; Yu, Chien-Mei; Wong, Cheng-Hsin; Peng, Robert Y

    2016-08-01

    Seven kinds of indigenous fruits and five imported fruits were compared for their "health quality." Methods including the calorific, antioxidant, and ion ratios were carried out. Results indicated the order of content (in mg/100g) was: Ca(2+) , Murcott orange (218.2) > Kiwifruit (200.0) > pineapple (138.5) > Golden kiwi (117.6); Mg(2+) , Pitaya (192.2), banana (88.0), Kiwifruit (63.4), and Golden kiwi (58.4); Zn(2+) , Pitaya (19.53) > pear (10.8) > Kiwifruit (6.09) > Irwin mango (4.58). Cu(2+) , Kiwifruit (0.70) > Red globe grape (0.67) > Golden kiwi (0.65) > Irwin mango (0.42) ≈ Pitaya (0.40). In terms of ion ratio, Pitaya showed Zn(2+) /Cu(2+) (48.8), Mg(2+) /Ca(2+) (6.7) and uniquely possessed selenium 0.002 mg/100 g; for pear, Zn(2+) /Cu(2+) = 37.2, while Kyoho grape, Red globe grape, and Golden kiwi revealed extremely high Fe(2+) /(Co(2+) +Ni(2+) ) ratios. On the other hands, Irwin mango and Pitaya astonishingly contained huge amount of inositol, reaching 3523.2 mg/100 g and 1998.7 mg/100 g, respectively. To evaluate the "health quality" of fruits, an overall ranking method by combining (a) the Function-directed Caloric Antioxidant Density (CAD) and (b) the ion ratio was developed. The finalized ranking of these selected fruits was: Pitaya > cherry > Irwin mango > Murcott orange = pineapple > banana > Golden kiwi > pear > Kiwifruit > Red globe grape > apple > Kyoho grape. Conclusively, this evaluation method is novel, contemporary and scientific, which could more clearly assess the "health quality" of fruits in view of nutritional, calorific, and antioxidant balance.

  20. Novel Approach of Using Nutraceutic-Directed Caloric Antioxidant Density and Ion-Ratio for Evaluating Fruit's Health Quality.

    Science.gov (United States)

    Hsieh, Chiu-Lan; Huang, Shang-Ming; Chen, Li-I; Yu, Chien-Mei; Wong, Cheng-Hsin; Peng, Robert Y

    2016-08-01

    Seven kinds of indigenous fruits and five imported fruits were compared for their "health quality." Methods including the calorific, antioxidant, and ion ratios were carried out. Results indicated the order of content (in mg/100g) was: Ca(2+) , Murcott orange (218.2) > Kiwifruit (200.0) > pineapple (138.5) > Golden kiwi (117.6); Mg(2+) , Pitaya (192.2), banana (88.0), Kiwifruit (63.4), and Golden kiwi (58.4); Zn(2+) , Pitaya (19.53) > pear (10.8) > Kiwifruit (6.09) > Irwin mango (4.58). Cu(2+) , Kiwifruit (0.70) > Red globe grape (0.67) > Golden kiwi (0.65) > Irwin mango (0.42) ≈ Pitaya (0.40). In terms of ion ratio, Pitaya showed Zn(2+) /Cu(2+) (48.8), Mg(2+) /Ca(2+) (6.7) and uniquely possessed selenium 0.002 mg/100 g; for pear, Zn(2+) /Cu(2+) = 37.2, while Kyoho grape, Red globe grape, and Golden kiwi revealed extremely high Fe(2+) /(Co(2+) +Ni(2+) ) ratios. On the other hands, Irwin mango and Pitaya astonishingly contained huge amount of inositol, reaching 3523.2 mg/100 g and 1998.7 mg/100 g, respectively. To evaluate the "health quality" of fruits, an overall ranking method by combining (a) the Function-directed Caloric Antioxidant Density (CAD) and (b) the ion ratio was developed. The finalized ranking of these selected fruits was: Pitaya > cherry > Irwin mango > Murcott orange = pineapple > banana > Golden kiwi > pear > Kiwifruit > Red globe grape > apple > Kyoho grape. Conclusively, this evaluation method is novel, contemporary and scientific, which could more clearly assess the "health quality" of fruits in view of nutritional, calorific, and antioxidant balance. PMID:27467811

  1. Caloric restriction protects against electrical kindling of the amygdala by inhibiting the mTOR signaling pathway

    Directory of Open Access Journals (Sweden)

    Bryan Victor Phillips-Farfan

    2015-03-01

    Full Text Available Caloric restriction (CR has been shown to possess antiepileptic properties; however its mechanism of action is poorly understood. CR might inhibit the activity of the mammalian or mechanistic target of rapamycin (mTOR signaling cascade, which seems to participate crucially in the generation of epilepsy. Thus, we investigated the effect of CR on the mTOR pathway and whether CR modified epilepsy generation due to electrical amygdala kindling. The former was studied by analyzing the phosphorylation of adenosine monophosphate-activated protein kinase, protein kinase B and the ribosomal protein S6. The mTOR cascade is regulated by energy and by insulin levels, both of which may be changed by CR; thus we investigated if CR altered the levels of energy substrates in the blood or the level of insulin in plasma. Finally, we studied if CR modified the expression of genes that encode proteins participating in the mTOR pathway. CR increased the after-discharge threshold and tended to reduce the after-discharge duration, indicating an anti-convulsive action. CR diminished the phosphorylation of protein kinase B and ribosomal protein S6, suggesting an inhibition of the mTOR cascade. However, CR did not change glucose, β-hydroxybutyrate or insulin levels; thus the effects of CR were independent from them. Interestingly, CR also did not modify the expression of any investigated gene. The results suggest that the anti-epileptic effect of CR may be partly due to inhibition of the mTOR pathway.

  2. Tratamiento conservador en pacientes con retinoblastoma bilateral

    OpenAIRE

    Juan C. Suárez; Mabel C. Ospina; Sandra A. Arias; González, María E

    2008-01-01

    OBJETIVO: comparar el tratamiento convencional del retinoblastoma bilateral, usado hasta hace algunos años, consistente en radioterapia o enucleación bilateral, con el tratamiento conservador actual que incluye termoterapia transpupilar (TTT) o TTT/quimioterapia al menos en un ojo, en niños con diagnóstico de retinoblastoma bilateral. DISEÑO: estudio retrospectivo descriptivo. MUESTRA: 20 pacientes con diagnóstico de retinoblastoma bilateral que consultaron al Hospital Universitario San Vicen...

  3. Depresion en pacientes con alteraciones del tiroides

    OpenAIRE

    Ljiljana Radanovic-Grguric´; Pavo Filakovic´; Jelena Barkic´; Nikola Mandic´; Ivan Karner; Juraj Smoje

    2003-01-01

    Nuestro estudio fue realizado en un grupo de 53 mujeres con disfunción tiroidea y 28 mujeres con depresión mayor. Empleamos la Escala de la Depresión de Hamilton, la Escala de Autoevaluación de la Depresión de Zung y la Escala sobre la Impresión Clínica Global. Los resultados del estudio demuestran que la mayoría de los pacientes con disfunción tiroidea se mostraron clínicamente significativos en cuanto al trastorno depresivo. Los episodios depresivos son más frecuentes en pacientes con hipot...

  4. Itinerari Musicali con la Wiild

    Directory of Open Access Journals (Sweden)

    Elisabetta Nanni

    2013-03-01

    Full Text Available La Wiild, acronimo di Wiimote Lavagna Digitale, è uno strumento didattico che utilizza il telecomando della Wii, il famoso gioco della Nintendo, insieme a un software libero, rendendolo così estremamente versatile. Non vincolato a software proprietario, il suo utilizzo è legato alla capacità dell’insegnante di ripartire dalla didattica, dalle risorse selezionate e dall’epistemologia di ogni singola disciplina, trovando così nel proprio contesto un ruolo per le tecnologie. Il contributo presenta ipotesi di lavoro per l’educazione musicale nella scuola secondaria di primo grado che si sviluppano sia attraverso lo studio del rapporto suono/segno con affinità pittoriche e successiva codificazione grafica, sia attraverso un’attività di laboratorio in cui co-costruire percorsi storico-musicali. La Wiild diventerà davvero utile ed efficace nel momento in cui, affiancando le risorse selezionate dal docente, verrà utilizzata senza essere notata, giocando un ruolo di strumento tecnologico «normale e trasparente».

  5. Adiciones y cementos con adiciones

    Directory of Open Access Journals (Sweden)

    Calleja, José

    1983-09-01

    Full Text Available The present paper deals with aspects concerning the conditions to be fulfilled by raw materials and manufacturing process of cements containing components other than clinker and setting regulator. It deals also with proper conditions for the utilization of these cements, as well as with the knowledge of the interrelation between manufacture and use of them, in order to aid the manufacturers and the users in the better profit o such energy saving blended cements in optimal technical and economical conditions.

    Se tratan en este trabajo aspectos relativos a las condiciones exigibles a las materias primas y a los procesos de fabricación de los cementos que contienen constituyentes distintos del clínker y del yeso. Se tienen también en cuenta las condiciones adecuadas para utilizar estos cementos, así como el conocimiento de las relaciones entre la fabricación y el empleo de los cementos con constituyentes secundarios que ahorran energía, a fin de ayudar a fabricantes y usuarios en su mejor aprovechamiento en condiciones técnicas y económicas óptimas.

  6. Estimación de propiedades térmicas de aleaciones con problema inverso

    Directory of Open Access Journals (Sweden)

    Zueco, J.

    2005-06-01

    Full Text Available This paper provides an efficient numerical method for estimating the thermal conductivity and heat capacity of alloys, as a function of the temperature, starting from temperature measurements (including errors in heating and cooling processes The proposed procedure is a modification of the known function estimation technique, typical of the inverse problem field, in conjunction with the network simulation method (already checked in many non-lineal problems as the numerical tool Estimations only require a point of measurement The methodology is applied for determining these thermal properties in alloys within ranges of temperature where allotropic changes take place These changes are characterized by sharp temperature dependencies

    Se presenta un método numérico eficaz para la estimación de las dependencias térmicas (conductividad y capacidad calorífica de aleaciones, a partir de medidas de temperatura (incluyendo el error, en procesos de calentamiento y/o enfriamiento. El protocolo propuesto combina una modificación de la clásica técnica de estimación de funciones, característica del problema inverso, con el método de simulación por redes como técnica de cálculo propiamente numérica ya probada para la solución de numerosos problemas no lineales. Las estimaciones sólo requieren un punto de medida. Se aplica esta metodología para obtener estimaciones en rangos de temperatura en los que producen transformaciones alotrópicas, caracterizadas por una dependencia muy acusada de estas propiedades con la temperatura.

  7. Toxicokinetics of chloral hydrate in ad libitum-fed, dietary-controlled, and calorically restricted male B6C3F1 mice following short-term exposure

    International Nuclear Information System (INIS)

    Chloral hydrate is widely used as a sedative in pediatric medicine and is a by-product of water chlorination and a metabolic intermediate in the biotransformation of trichloroethylene. Chloral hydrate and its major metabolite, trichloroacetic acid, induce liver tumors in B6C3F1 mice, a strain that can exhibit high rates of background liver tumor incidence, which is associated with increased body weight. This report describes the influence of diet and body weight on the acute toxicity, hepatic enzyme response, and toxickinetics of chloral hydrate as part of a larger study investigating the carcinogenicity of chloral hydrate in ad libitum-fed and dietary controlled mice. Dietary control involves moderate food restriction to maintain the test animals at an idealized body weight. Mice were dosed with chloral hydrate at 0, 50, 100, 250, 500, and 1000 mg/kg daily, 5 days/week, by aqueous gavage for 2 weekly dosing cycles. Three diet groups were used: ad libitum, dietary control, and 40% caloric restriction. Both dietary control and caloric restriction slightly reduced acute toxicity of high doses of chloral hydrate and potentiated the induction of hepatic enzymes associated with peroxisome proliferation. Chloral hydrate toxicokinetics were investigated using blood samples obtained by sequential tail clipping and a microscale gas chromatography technique. It was rapidly cleared from serum within 3 h of dosing. Trichloroacetate was the major metabolite in serum in all three diet groups. Although the area under the curve values for serum trichloroacetate were slightly greater in the dietary controlled and calorically restricted groups than in the ad libitum-fed groups, this increase did not appear to completely account for the potentiation of hepatic enzyme induction by dietary restriction

  8. The nature of heat: after two centuries, will it be that the caloric theory is still in some way an attractive idea or, even, useful?

    Directory of Open Access Journals (Sweden)

    Antônio Bráz de Pádua

    2009-03-01

    Full Text Available In the beginning of the 19th Century, there were two theories absolutely different on the nature of the heat: the Mechanical Theory of the Heat and the Caloric Theory. For the first theory, heat was considered as ‘a vibration’ of the atoms that compose the matter. Thus, the temperature represented the intensity of those vibrations and their propagation was a transfer of heat. When two bodies of different temperatures were put in contact, the atoms of the hottest body communicated part of its vibrations to that of the coldest body by means of collisions until the atoms of both bodies vibrated with the same intensities. For the second theory, the heat was considered a subtle fluid that filled the interior of the bodies. Spread all over the nature, that fluid was propagated or conserved by the bodies according to their properties and temperatures. Before being replaced by the conception of heat as a form of energy, in the middle of the 19th Century, the Caloric Theory reached great successes with the works of Jean-Baptiste Fourier (1768 – 1830 in 1822, Sadi Carnot (1796 – 1832, in 1824 and Émile Clapeyron (1799 – 1864 in 1834. By means of a careful revision of the analytic results of Clapeyron, developed under the basis of the Caloric Theory, we propose in this work to re-adapt these results and to compare them with current experimental data and theories, and to show that we can still understand some characteristics of the thermal phenomena, without considering heat as a form of energy. Especially in the study of the gases, we could obtain objective and precise information about absorption and liberation of heat in the isothermal processes, efficiency of the thermal machine of Carnot and the relationship among specific heats.

  9. Determinação do calor de dessorção para materiais têxteis = Determining heat of desorption for textile materials

    Directory of Open Access Journals (Sweden)

    Gracielle Johann

    2010-01-01

    Full Text Available O presente trabalho tem como objetivo o cálculo do calor de dessorção da umidade, durante a secagem de materiais têxteis, utilizando o método de Othmer, que correlaciona a pressão de vapor e o calor latente de vaporização. Foram utilizados dados da literatura para as isotermas de dessorção de dois diferentes tipos de materiais têxteis (sarja e meia-malha. Os resultados obtidos apresentaram a quantidade de energia necessária para a dessorção da umidade ligada à fibra dos materiais têxteis durante sua secagem. À medida que a quantidade de umidade livre diminui, a quantidade de energia requerida ao processo de dessorção aumenta. A equação determinada para a obtenção do calor de dessorção, em função da unidade de equilíbrio, apresentou uma correlação de 0,999, para ambos os materiais têxteis, para indicar qualidade nos parâmetros obtidos. The objective of this paper is to calculate the heat of desorption of moisture during the drying of textile materials, using the Othmer method, which correlates steam pressure and the latent heat ofvaporization. Data from the literature were used for the desorption isotherms of two different textile material types (denim and cotton-elastane. The results obtained presented the amount of energy required for desorption of moisture linked to the fiber of textilematerials during drying. As the amount of free moisture decreases, the amount of energy required for the process of desorption increases. The equation determined to obtain the heat of desorption, as a function of equilibrium moisture, presented a correlation of 0.999 for both textile materials, which indicates quality in the obtained parameters.

  10. IDENTIFICAÇÃO DE ILHAS DE CALOR POR MEIO DE SENSORIAMENTO REMOTO: ESTUDO DE CASO NO MUNICÍPIO DE GOIÂNIA – GO/2001

    Directory of Open Access Journals (Sweden)

    Diego Tarley Ferreira Nascimento

    2009-06-01

    Full Text Available No presente trabalho são utilizadas técnicas de sensoriamento remoto para identificação e análise do fenômeno de ilhas de calor em Goiânia-GO, tendo como recorte temporal o ano de 2001. Foi utilizada a proposta metodológica de Monteiro (1976, do Sistema de Clima Urbano – SCU, em particular o subsistema Termodinâmico, visando proceder a uma análise do funcionamento, desempenho e organização do fenômeno de ilhas de calor. A elaboração do trabalho baseou-se na classificação da cobertura do solo e em um mapeamento do campo térmico do município de Goiânia, por meio das imagens das bandas 3, 4, 5 e 6 (banda termal do Landsat 7, nas quais foram considerados como instrumentos de análise: a urbanização, as características geoecológicas (topografia e o sistema meteorológico (clima regional. Os resultados demonstram que o fenômeno de ilha de calor é constatado no município de Goiânia, havendo diferenças de temperatura de até 10°C entre a área urbana e a rural do município, sendo possível caracterizar determinados usos antrópicos (classes de cobertura do solo e intervalos altimétricos como potencializadores de maiores valores de temperatura.

  11. Prevention of Neuromusculoskeletal Frailty in Slow-Aging Ames Dwarf Mice: Longitudinal Investigation of Interaction of Longevity Genes and Caloric Restriction

    OpenAIRE

    Arum, Oge; Rasche, Zachary Andrew; Rickman, Dustin John; Bartke, Andrzej

    2013-01-01

    Ames dwarf (Prop1 df/df ) mice are remarkably long-lived and exhibit many characteristics of delayed aging and extended healthspan. Caloric restriction (CR) has similar effects on healthspan and lifespan, and causes an extension of longevity in Ames dwarf mice. Our study objective was to determine whether Ames dwarfism or CR influence neuromusculoskeletal function in middle-aged (82 ± 12 weeks old) or old (128 ± 14 w.o.) mice. At the examined ages, strength was improved by dwarfism, CR, and d...

  12. Ecuación hiperbólica de transmisión del calor para el estudio de la ablación corneal

    OpenAIRE

    Berjano Zanón, Enrique; López Molina, Juan Antonio; Rivera Ortún, María José; Trujillo Guillén, Macarena

    2007-01-01

    En este trabajo presentamos el estudio del problema de transmisión del calor que se produce en el proceso de ablación de la córnea humana por radiofrecuencia, tal es el caso de la queratoplastia conductiva para la corrección de la hipermetropía y/o el astigmatismo mediante el empleo de electrodos intracorneales de muy pequeñas dimensiones. En estos casos, las distancias de interés son lo suficientemente pequeñas y los tiempos de excitación lo suficientemente cortos, como para que el est...

  13. Influencia en la eficiencia energética de los refrigerantes utilizados y elementos de los equipos de bomba de calor

    OpenAIRE

    Muñor Rico, Juan-Ramón

    2016-01-01

    Se muestra que aunque cualitativamente el comportamiento energético de los sistemas de refrigeración y bomba de calor por compresión simple de vapor es similar, no lo es si se analiza desde un punto de vista cuantitativo. Se desarrolla un software propio (RefCOMP) que sirve para contrastar el comportamiento termodinámico de los refrigerantes a partir de la comparación de sus respectivos diagramas de estado. Se analiza el software existente para el modelado de este tipo de sistemas y, empleand...

  14. Revisión general de la transferencia de calor por ebullición en película en piscina

    OpenAIRE

    Arévalo Ramírez, Rubén; Rebollo Medrano, Luis; Abánades Velasco, Alberto; Muñoz Antón, Javier; Omaña, Rubén; Pérez, Orlando

    2007-01-01

    La ebullición en película es el mecanismo de transferencia de calor básico que acopla térmicamente un líquido, saturado o subenfriado, y una superficie caliente cuando existe una gran diferencia de temperatura entre ambos. Dicho mecanismo presenta la complejidad física asociada a la existencia de una capa límite convectiva de vapor en torno a la superficie caliente, así como al acoplamiento térmico radiante entre la superficie y los dos medios participativos que la rodean (vapor y líquido). E...

  15. El efecto del calentamiento global sobre las temperaturas medias y los fenómenos de calor extremo en Castellón

    OpenAIRE

    Ginés Llorens, Fernando

    2015-01-01

    El cambio climático ha pasado de ser una mera especulación a una preocupante realidad. En el presente estudio se ha analizado cómo está afectando el calentamiento global a las temperaturas de la ciudad de Castellón, especialmente a las medias anuales y a las máximas estivales, así como a la frecuencia e intensidad de los episodios de calor extremo. Así mismo, se han analizado la evolución que experimentaron las temperaturas de Castellón en el pasado y los episodios extremos más destacables de...

  16. La recuperación termoeléctrica del calor residual, una fuente de energía ambientalmente amigable

    OpenAIRE

    Rodríguez, Julio E.

    2012-01-01

    El incremento del precio de los combustibles fósiles acompañado por el deterioro medioambiental asociado al calentamiento global generó un incremento en la actividad científica dirigida a identificar y desarrollar fuentes de potencia eléctrica no contaminantes. En este sentido, la conversión directa de energía térmica en eléctrica mediante dispositivos termoeléctricos utilizando calor residual como fuente de calentamiento, podría contribuir a solucionar los problemas energéticos de la socieda...

  17. UNA ISLA QUE SE MUEVE (Aproximación a la isla de calor urbana de Algemesí, Valencia y su aprovechamiento didáctico

    Directory of Open Access Journals (Sweden)

    Enric Ramiro y Roca

    2006-12-01

    Full Text Available La constatación de la existencia de la isla de calor urbana en pequeñas localidades de 25.000 habitantes es el núcleo de esta investigación. El proceso que se ha seguido para desarrollar esta experiencia en alumnos de secundaria dentro de la asignatura de Ciencias Sociales: Geografía e Historia, y su aprovechamiento didáctico, son los dos ejes que recorre el artículo para invitar a su realización en otros lugares.

  18. Utilización de equinoterapia como instrumento terapéutico en el tratamiento de niños con parálisis cerebral

    OpenAIRE

    Fourmatin, Gisela

    2012-01-01

    A la equinoterapia se la conoce como la alternativa terapéutica que utiliza al caballo como un instrumento terapéutico, y a las técnicas ecuestres para lograr la rehabilitación física, mental, social y temperamental de algunas personas con deficiencias en estas áreas. Esta se realiza a través de la trasmisión del calor corporal del caballo, del impulso rítmico y del patrón de locomoción tridimensional, equivalente al patrón fisiológico de la marcha humana. La equinoterapia se divide en tre...

  19. Identificación molecular de Escherichia coli enterotoxigénica en niños con infecciones diarreicas agudas mediante la Reacción en Cadena de la Polimerasa

    Directory of Open Access Journals (Sweden)

    Marx Peña-Hidalgo

    2015-01-01

    Full Text Available Las infecciones diarreicas agudas (IDAs son problemas comunes en niños menores de 5 años en nuestro país y la Región Loreto. Sin embargo, se desconocen los agentes microbiológicos causales de estas infecciones. Para cubrir estos vacíos en el conocimiento, el objetivo de esta investigación fue realizar la identificación molecular de Escherichia coli enterotoxigénica (ECET en niños con infecciones diarreicas agudas mediante la Reacción en Cadena de la Polimerasa (PCR. Se colectaron 188 muestras diarreicas de niños menores de cinco años de siete Centros de Salud de Iquitos. A partir de estas se aislaron cepas de E. coli, se extrajo el ADN y amplificó regiones de los genes que codifican las enterotoxinas lábil al calor (LT y estable al calor (ST. De los 188 casos con IDAs se ha encontrado que ~83% son atribuibles a infecciones por cepas de E. coli y de estas ~18% fueron identificadas molecularmente como ECET por presentar el gen LT (19 o el gen ST (9. En conclusión, la mayoría de las IDAs en niños < 5 años de Iquitos están asociadas con cepas de E. coli. Una fracción importante de estas cepas han sido identificadas molecularmente (mediante PCR y demostrado que pertenecen al patotipo ECET. Asimismo, se ha evidenciado que las cepas ECET portadoras del gen LT predominan con respecto a las que tienen el gen ST y no se ha encontrado cepas ECET que porten de forma simultánea ambos genes.

  20. Influence of caloric restriction on constitutive expression of NF-κB in an experimental mouse astrocytoma.

    Directory of Open Access Journals (Sweden)

    Tiernan J Mulrooney

    Full Text Available BACKGROUND: Many of the current standard therapies employed for the management of primary malignant brain cancers are largely viewed as palliative, ultimately because these conventional strategies have been shown, in many instances, to decrease patient quality of life while only offering a modest increase in the length of survival. We propose that caloric restriction (CR is an alternative metabolic therapy for brain cancer management that will not only improve survival but also reduce the morbidity associated with disease. Although we have shown that CR manages tumor growth and improves survival through multiple molecular and biochemical mechanisms, little information is known about the role that CR plays in modulating inflammation in brain tumor tissue. METHODOLOGY/PRINCIPAL FINDINGS: Phosphorylation and activation of nuclear factor κB (NF-κB results in the transactivation of many genes including those encoding cycloxygenase-2 (COX-2 and allograft inflammatory factor-1 (AIF-1, both of which are proteins that are primarily expressed by inflammatory and malignant cancer cells. COX-2 has been shown to enhance inflammation and promote tumor cell survival in both in vitro and in vivo studies. In the current report, we demonstrate that the p65 subunit of NF-κB was expressed constitutively in the CT-2A tumor compared with contra-lateral normal brain tissue, and we also show that CR reduces (i the phosphorylation and degree of transcriptional activation of the NF-κB-dependent genes COX-2 and AIF-1 in tumor tissue, as well as (ii the expression of proinflammatory markers lying downstream of NF-κB in the CT-2A malignant mouse astrocytoma, [e.g. macrophage inflammatory protein-2 (MIP-2]. On the whole, our date indicate that the NF-κB inflammatory pathway is constitutively activated in the CT-2A astrocytoma and that CR targets this pathway and inflammation. CONCLUSION: CR could be effective in reducing malignant brain tumor growth in part by

  1. Effects of fructose-containing caloric sweeteners on resting energy expenditure and energy efficiency: a review of human trials.

    Science.gov (United States)

    Tappy, Luc; Egli, Leonie; Lecoultre, Virgile; Schneider, Pascal

    2013-01-01

    Epidemiological studies indicate that the consumption of fructose-containing caloric sweeteners (FCCS: mainly sucrose and high-fructose corn syrup) is associated with obesity. The hypothesis that FCCS plays a causal role in the development of obesity however implies that they would impair energy balance to a larger extent than other nutrients, either by increasing food intake, or by decreasing energy expenditure. We therefore reviewed the literature comparing a) diet-induced thermogenesis (DIT) after ingestion of isocaloric FCCS vs glucose meals, and b) basal metabolic rate (BMR) or c) post-prandial energy expenditure after consuming a high FCCS diet for > 3 days vs basal,weight-maintenance low FCCS diet. Nine studies compared the effects of single isocaloric FCCS and glucose meals on DIT; of them, six studies reported that DIT was significantly higher with FCCS than with glucose, 2 reported a non-significant increase with FCCS, and one reported no difference. The higher DIT with fructose than glucose can be explained by the low energy efficiency associated with fructose metabolism. Five studies compared BMR after consumption of a high FCCS vs a low FCCS diet for > 3 days. Four studies reported no change after 4-7 day on a high FCCS diet, and only one study reported a 7% decrease after 12 week on a high FCCS diet. Three studies compared post-prandial EE after consumption of a high FCCS vs a low FCCS diet for > 3 days, and did not report any significant difference. One study compared 24-EE in subjects fed a weight-maintenance diet and hypercaloric diets with 50% excess energy as fructose, sucrose and glucose during 4 days: 24-EE was increased with all 3 hypercaloric diets, but there was no difference between fructose, sucrose and glucose. We conclude that fructose has lower energy efficiency than glucose. Based on available studies, there is presently no hint that dietary FCCS may decrease EE. Larger, well controlled studies are however needed to assess the longer

  2. Características y diferencias entre recién nacidos intervenidos con la bolsa corporal de polietileno y el secado convencional durante la Adaptación neonatal en la Sede Materno Infantil del Hospital la Victoria y el Hospital de Engativá, Bogotá, 2013

    OpenAIRE

    Montilla Velásquez, María del Pilar

    2014-01-01

    INTRODUCCION: La hipotermia en el recién nacido es causa condiciones mórbidas. En países en vía de desarrollo la tecnología básica para la adaptación neonatal puede no estar disponible. Las bolsas de polietileno pueden ser alternativas a la lámpara de calor radiante para evitar hipotermia OBJETIVO: Caracterizar las diferencias entre Recién nacidos a término intervenidos con Bolsa corporal de polietileno o secado convencional durante la adaptación neonatal en la Sede Materno ...

  3. Tratamiento de aguas residuales con humedales artificiales en Tlapanaloya, municipio de Tequisquiac, Estado de México.

    OpenAIRE

    Avelar Roblero, Juan Uriel

    2011-01-01

    La presente tesis tiene como objeto proponer, mostrar y validar una alternativa basada en el uso y acondicionamiento de humedales artificiales, para resolver el problema de salud pública y contaminación ambiental que genera la descarga de aguas residuales. El campo de estudio y evaluación fue la cabecera municipal de Hueypoxtla, Estado de México, cuyas aguas residuales vierten directamente al cauce del Río Salado, el cual cruza por la comunidad de Tlapanaloya, municipio de Tequisquiac, Estado...

  4. Glucocorticoid antagonism limits adiposity rebound and glucose intolerance in young male rats following the cessation of daily exercise and caloric restriction.

    Science.gov (United States)

    Teich, Trevor; Dunford, Emily C; Porras, Deanna P; Pivovarov, Jacklyn A; Beaudry, Jacqueline L; Hunt, Hazel; Belanoff, Joseph K; Riddell, Michael C

    2016-07-01

    Severe caloric restriction (CR), in a setting of regular physical exercise, may be a stress that sets the stage for adiposity rebound and insulin resistance when the food restriction and exercise stop. In this study, we examined the effect of mifepristone, a glucocorticoid (GC) receptor antagonist, on limiting adipose tissue mass gain and preserving whole body insulin sensitivity following the cessation of daily running and CR. We calorically restricted male Sprague-Dawley rats and provided access to voluntary running wheels for 3 wk followed by locking of the wheels and reintroduction to ad libitum feeding with or without mifepristone (80 mg·kg(-1)·day(-1)) for 1 wk. Cessation of daily running and CR increased HOMA-IR and visceral adipose mass as well as glucose and insulin area under the curve during an oral glucose tolerance test vs. pre-wheel lock exercised rats and sedentary rats (all P exercise and CR there are GC-induced mechanisms that promote adipose tissue mass gain and impaired metabolic control in healthy organisms and that this phenomenon can be inhibited by the GC receptor antagonist mifepristone. PMID:27143556

  5. 中国部分城市生活垃圾热值的分析%Analysis on caloric value of Chinese cities' municipal solid waste.

    Institute of Scientific and Technical Information of China (English)

    李晓东; 陆胜勇; 徐旭; 严建华; 池湧

    2001-01-01

    在收集和整理大量中国城市生活垃圾数据的基础上,进行工业分析和元素分析,提出了较适合中国城市生活垃圾热值的估算公式,并对中国垃圾的成分与热值的关系作了分析探讨,为各城市寻找适宜的垃圾处理方法特别是垃圾焚烧法提供了参考.%On the basis of collecting and arranging lots of data of municipal solid waste (MSW) of Chinese cities, industrical and elemental analyses and estimate have been done. A formula suited for estimating Chinese MSW's caloric value is put forward, and the relationship between MSW ingredients and caloric value is also discussed, offering reference for Chinese cities' looking for fit MSW treatments, especially MSW incineration technique.

  6. Prediction of Short-Term Outcome in Acute Superior Vestibular Nerve Failure: Three-Dimensional Video-Head-Impulse Test and Caloric Irrigation

    Directory of Open Access Journals (Sweden)

    Holger A. Rambold

    2015-01-01

    Full Text Available This retrospective study examines acute unilateral vestibular failure (up to seven days after onset with modern vestibular testing (caloric irrigation and video-head-impulse test, vHIT in 54 patients in order to test if the short-term outcome of the patients depends on the lesion pattern defined by the two tests. Patients were grouped according to a pathological unilateral caloric weakness without a pathological vHIT: group I; additional a pathological vHIT of the lateral semicircular canal (SCC: group II; and an additional pathological vHIT of the anterior SCC: group III. Patients with involvement of the posterior SCC were less frequent and not included in the analysis. Basic parameters, such as age of the subjects, days after symptom onset, gender, side of the lesion, treatment, and dizziness handicap inventory, were not different in groups I to III. The frequency of pathological clinical findings and pathological quantified measurements increased from groups I to III. The outcome parameter “days spent in the hospital” was significantly higher in group III compared to group I. The analysis shows that differential vestibular testing predicts short-term outcome of the patients and might be in future important to treat and coach patients with vestibular failure.

  7. Differential caloric intake in overweight females with and without binge eating: effects of a laboratory-based emotion-regulation training.

    Science.gov (United States)

    Svaldi, J; Tuschen-Caffier, B; Trentowska, M; Caffier, D; Naumann, E

    2014-05-01

    Negative emotions are among the best predictors for the occurrence of binge eating attacks in binge eating disorder (BED). Evidence from self-report and experimental studies suggests that this link may be mediated by deficits in emotion regulation (ER). Therefore, the aim of the present study was to experimentally test the effects of a short laboratory-based ER training on caloric intake in BED. Thirty-nine women with BED and 42 overweight females without BED were randomly assigned to a laboratory-based ER training focusing on either expressive suppression or cognitive reappraisal. They were then given a negative mood induction with the instruction to adopt the learned ER strategy, which was followed by a bogus taste-test. Independent of group membership, caloric intake was significantly higher in the suppression compared to the reappraisal condition. Furthermore, the BED group displayed significantly higher habitual suppression and significantly lower habitual reappraisal scores than the overweight group. The data suggest that therapeutic interventions focusing on the mediation of more adaptive affect-regulation skills may be useful for the reduction of binge eating episodes. PMID:24650627

  8. Energy saving in heat exchangers of industrial refrigeration systems; Ahorro de energia en intercambiadores de calor en los sistemas de refrigeracion industrial

    Energy Technology Data Exchange (ETDEWEB)

    Padilla, A.; Romero Paredes, Hernando; Ambriz, Juan Jose [Universidad Autonoma Metropolitana-Iztapalapa, Mexico, D. F. (Mexico)

    1994-12-31

    This paper presents the energy losses of the heat exchangers utilized in industrial refrigeration systems . The effects of the different scaling products on the heat transfer rates are presented and the energy not transferred because of them is evaluated. A simplified method for the evaluation is developed and applied to the evaporators and condensers more frequently employed in the industrial refrigeration systems. The internal and external heat transfer coefficients are evaluated in different types of heat exchangers. The energy losses as a function of the scale thickness on the heat exchanger is shown. [Espanol] El trabajo presenta las perdidas energeticas que se tienen en los intercambiadores de calor usados en los sistemas de refrigeracion industrial. Se presentan los efectos que tienen los diferentes incrustantes en las tasas de transferencia de calor y se evalua la energia que no se transfiere causada por aquellos. Se desarrolla un metodo simplificado de evaluacion y se aplica a los evaporadores y condensadores mas comunes empleados en los sistemas de refrigeracion industrial. Se evaluan los coeficientes internos y externos en diferentes tipos de intercambiadores. Se muestran las perdidas energeticas en funcion del espesor del incrustante en la pared del intercambiador.

  9. Tratamiento conservador en pacientes con retinoblastoma bilateral

    Directory of Open Access Journals (Sweden)

    Juan C. Suárez

    2008-11-01

    Full Text Available OBJETIVO: comparar el tratamiento convencional del retinoblastoma bilateral, usado hasta hace algunos años, consistente en radioterapia o enucleación bilateral, con el tratamiento conservador actual que incluye termoterapia transpupilar (TTT o TTT/quimioterapia al menos en un ojo, en niños con diagnóstico de retinoblastoma bilateral. DISEÑO: estudio retrospectivo descriptivo. MUESTRA: 20 pacientes con diagnóstico de retinoblastoma bilateral que consultaron al Hospital Universitario San Vicente de Paúl, de Medellín, Colombia, entre 1997 y 2007. MÉTODO: se hizo enucleación del ojo con el tumor de mayor tamaño. En el otro ojo se hizo tratamiento con TTT, con el láser diodo (810 nm, spot amplio, solo o combinado con otras terapias. RESULTADOS: se dividió a los pacientes en dos grupos: 16 pacientes (32 ojos en el grupo 1 tratados conservadoramente y 4 pacientes (8 ojos en el grupo 2 con tratamiento convencional. El rango de edad fue de 1-72 meses en el grupo 1 y de 1-12 meses en el grupo 2. El tiempo de seguimiento fue de 7-67 meses para el grupo 1 y de 13-73 meses para el grupo 2. En el grupo 1 se hizo enucleación de 16 ojos (50%, radioterapia externa de uno (3,1%, quimioterapia más termoterapia de 5 (15,6% y quimioterapia más termoterapia más crioterapia de 10 (31,3%. En todos los pacientes se logró preservar al menos un ojo. En el grupo 2, se enuclearon 7 ojos (87,5% y se hizo radioterapia externa más enucleación en un paciente (12.5%. Además, todos los pacientes recibieron quimioterapia. CONCLUSIÓN: la terapia conservadora actual consistente en tratamiento local (termoterapia, crioterapia o braquiterapia y quimiorreducción permite preservar al menos un ojo y en algunos casos de los dos, muchas veces con buena agudeza visual, en niños con retinoblastoma bilateral; se evitan así la enucleación bilateral y la radioterapia externa usada en el tratamiento convencional con todos sus efectos secundarios. La enucleación contin

  10. Fonones en cristales con estructura de diamante

    OpenAIRE

    F. L. Pérez Sánchez; F. Pérez Rodríguez

    2004-01-01

    Se presenta un estudio de los modos vibracionales de cristales con estructura de diamante. En este estudio aplicamos el modelo de Keating para describir las interacciones de corto alcance entre los átomos e incorporar, en la forma más simple, las interacciones de tres cuerpos asociadas con la deformación del ángulo entre dos enlaces covalentes. En el marco de la aproximación armónica, se obtienen expresiones analíticas para las relaciones de dispersión de fonones con vectores de onda a lo lar...

  11. Reflexiones de un objeto con mente

    OpenAIRE

    Viader Junyent, Manel

    1993-01-01

    A estas alturas, y conociendo en parte su trayectoria, no resulta ninguna sorpresa para el lector avezado o al menos interesado en la problematica de la psicologia cognitiva que el profesor Ángel Riviere nos presente un libro como Objetos con mente. Por el contrario, se trata de un trabajo coherente con las reflexiones que viene aportando desde hace años a la tematica, y comparte con sus libros anteriores altos niveles de rigor y profundidad. Desde luego, los trabajos de Riviere rompen totalm...

  12. Posicionamiento WIFI con variaciones de fingerprint

    OpenAIRE

    Kornuta, Carlos; Acosta, Nelson; Toloza, Juan Manuel

    2013-01-01

    Los sistemas de posicionamiento Indoor estiman la posición de un dispositivo móvil en un entorno cerrado con una precisión relativa. Existen diversas técnicas de posicionamiento, donde el parámetro mayormente utilizado es el RSSI (Received Signal Strength Indicator). En este artículo se analiza la técnica Fingerprint con la finalidad de estimar el margen de error obtenido con la distancia euclidiana como métrica principal. Se presentan variantes de la construcción de la base de datos Fingerpr...

  13. El envejecimiento de las personas con discapacidad

    OpenAIRE

    Envejecimiento Activo, CERMI

    2012-01-01

    El envejecimiento activo es considerado como un concepto multidimensional que abarca y supera la buena salud, resultado de un amplio conjunto de factores biológicos, psicológicos y sociales. En el caso de las personas mayores con discapacidad, la ausencia de una política de promoción y sensibilización en la comunidad a veces les niega la igualdad de oportunidades en relación con el resto de los ciudadanos. Para desarrollar ese potencial de envejecimiento activo en personas con discapacidad ha...

  14. Portal de compraventa con red social

    OpenAIRE

    Montero Vegas, Toni

    2010-01-01

    Este proyecto ha sido diseñado con la intención de añadir una aplicación a la red en la que un usuario que disponga de una necesidad, ya sea de compra o de venta, de un articulo pueda disponer de un medio más para vender en el que además, pueda hacer amistad con otros usuarios y que pueda interaccionar con todos estos usuarios, tanto amigo como simples usuarios bajo su punto de vista. Para poder realizar el proyecto, se han utilizado frameworks existentes como por ejemplo Ibatis, para la c...

  15. Aislamiento térmico producido a partir de cascarilla de arroz aglomerada utilizando almidón producido con saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Jaime Gutiérrez M.D.

    2014-01-01

    Full Text Available Se aglomeró cascarilla de arroz usando almidones con el fin de obtener un material con estabilidad física adecuada, sin afectar su capacidad aislante. Para esto, se desarrolló un proceso que integró Saccharomyces Cerevisiae (SC como elemento productor de porosidades en el material. Posteriormente se sometieron las probetas a pruebas de resistencia al calor, flexión y finalmente a la norma ASTM C 177, para evaluar su conductividad térmica. De esta forma, se encontró que el aglomerado al ser sometido a fuego directo no produce llama (ignifugo, tiene una resistencia a la rotura entre 80 – 120 kPa al ser sometido a temperaturas entre 150 y 200 °C, la conductividad térmica del aglomerado se encuentra alrededor de 0,09 W/m.K. El aglomerado se dejó a la intemperie (Temperatura de bulbo seco: 30°C ± 5°C, Humedad relativa: 80% ± 15%, donde su estabilidad química se aprecia al no ser atacado por hongos, y su biodegradabilidad se manifiesta al ser disuelto por agua. Estos valores muestran que el aglomerado a base de cascarilla de arroz es un aislante térmico eficiente, con una estabilidad física y química adecuada para aplicaciones civiles.

  16. Modelación numérica de un proceso térmico por microondas con énfasis en alimentos

    Directory of Open Access Journals (Sweden)

    HÉCTOR JOSÉ CIRO VELÁSQUEZ

    2006-01-01

    Full Text Available En esta de investigación se simuló un proceso de esterilización térmica por microondas con énfasis en alimentos usando la técnica de diferenciación finita aplicada a volúmenes de control en coordenadas esféricas con dependencia espacial radial y en estado transitorio, donde el efecto electromagnético del proceso de microondas fue modelado a través de la ley de Lambert y cuyo algoritmo de solución fue programado en MatLab. Los resultados de la simulación mostraron que el algoritmo desarrollado es independiente de la red nodal seleccionada, permitiendo cuantificar las curvas de penetración de calor en función de la frecuencia y potencia del campo electromagnético, y para lo cual para una frecuencia de 915 MHz se proporciona un calentamiento más uniforme en el alimento debido a mayores profundidades de penetración de onda con respecto al uso de frecuencias de 2450 MHz.

  17. Estudo técnico-económico para otimização do projeto e implementação de uma bomba de calor "heat machine"

    OpenAIRE

    Silva, Luis Carlos Diniz da

    2015-01-01

    A gestão sustentável de calor residual produzido em processos de arrefecimento em sistemas de Aquecimento, Refrigeração e Ar Condicionado (AVAC), tem recebido uma especial atenção nos últimos anos. O aproveitamento do calor normalmente desperdiçado por estes sistemas para o meio ambiente, pode resultar em poupanças energéticas significativas. Em colaboração com as empresas “ACET Engenharia e Termodinâmica” e “Recipharm”, observou-se a possibilidade de implementar um sistem...

  18. Dynamic simulation of an office with windows with solar control filter: cases in Mexico and Canada; Simulacion dinamica de una oficina con una ventana con filtro de control solar: casos en Mexico y Canada

    Energy Technology Data Exchange (ETDEWEB)

    Gijon Rivera, M. A.; Alvarez Garcia, G.; Xaman Villasenor, J. [Centro Nacional de Investigacion y Desarrollo Tecnologico, CENIDET-DGEST-SEP, Cuernavaca, Morelos (Mexico)]. E-mail: gaby@cenidet.edu.mx; I. Beausoleil-Morrison [Department of Mechanical and Aerospace Engineering, Carleton University, Ottawa (Canada)]. E-mail: ibeausol@mae.carleton.ca

    2010-11-15

    The use of solar passive strategies in buildings with large glazed areas such as new solar control coatings in windows are becoming more important and helpful recently, mainly because those developments can help to reduce heat gains and/or losses through transparent materials, reduce energy consumption, and improving the environment inside buildings. This paper presents an assessment of thermal performance in an office building with a SnS-Cu{sub x}S solar control coating and its influence on indoor conditions. The simulations consider climates of Mexico city and Ottawa as a good representation of two extremely conditions to asses the thermal behaviour inside offices, energy consumption, costs for air conditioning, and the influence of interior heat transfer coefficient correlations on energy consumption. The results are shown with and without the solar control coating adhered in a clear glass and in a double window configuration. The case of the system glass-film is the worst configuration as result of the high temperatures in the internal surface impacting the air point temperature and increasing the energy consumption. In general, the double glass configuration presents the best conditions, showing higher benefits for the case in Mexico City than the case of Ottawa. [Spanish] Resulta importante implementar estrategias pasivas en estudios de edificaciones con grandes areas de ventanas, como es la implementacion de nuevos materiales de control solar en vidrios que ayudan a reducir las ganancias y/o perdidas de calor a traves de los materiales transparentes, y asi reducir el consumo de energia y mejorar las condiciones del confort interior de los edificios. Este estudio realiza una evaluacion del funcionamiento termico de una pelicula selectiva de SnS-Cu{sub x}S que permite algunas ventajas termicas y opticas en el ambiente interno. Las simulaciones dinamicas consideran climas de la Ciudad de Mexico y Ottawa , con resultados que muestran las condiciones de confort

  19. Islas de calor urbano en Tampico, México. Impacto del microclima a la calidad del hábitat

    OpenAIRE

    Carlos Alberto Fuentes Pérez

    2014-01-01

    De todas las modificaciones climáticas por causa urbana, las térmicas son las más conocidas por los propios ciudadanos. La acción transformadora del espacio natural sobre el que se realiza el emplazamiento de la ciudad, llega a ser productora en gran medida de sus condiciones ambientales, incluida la climatología urbana. Todo proceso de urbanización sustituye los suelos y áreas naturales por superficies construidas, cuyos materiales se caracterizan por una baja reflectividad, con disminución ...

  20. Presa con revestimiento asfáltico

    Directory of Open Access Journals (Sweden)

    Proudfit, D. P.

    1960-07-01

    Full Text Available La presa denominada Montgomery se halla situada sobre el río South Platte River, a unos 8 km aguas arriba de la ciudad de Alma, del Estado de Colorado (EE. UU., y en la ladera oriental de la cordillera Continental Divide. El cuerpo o dique de esta presa está constituido por piedra, revestida con una capa de hormigón asfáltico en el paramento de contacto con el agua.

  1. Infactibilidad en programas con restricciones lineales

    Directory of Open Access Journals (Sweden)

    Liern Carrión, V.

    1999-01-01

    Full Text Available En este trabajo resumimos las técnicas más habituales que permiten diagnosticar las causas de infactibilidad de programas con restricciones lineales. Además, presentamos dos métodos que, con las mínimas transformaciones posibles del modelo inicial, permiten hacer viable un programa infactible. Los métodos descritos son aplicados a un modelo de selección de carteras eficientes.

  2. RadCon: A Radiological Consequences Model

    International Nuclear Information System (INIS)

    RadCon estimates the dose received by user selected groups in the population from an accidental release of radionuclides to the environment. The exposure pathways considered are external exposure from the cloud and ground and internal exposure from inhalation and ingestion of contaminated food. Atmospheric dispersion modelling is carried out externally to RadCon.Given a two dimensional time varying air and ground concentration of radioactive elements, RadCon allows the user to: view the air and ground concentration over the affected area, select optional parameters and calculate the dose to people,display the results to the user, and change the parameter values. RadCon offers two user interfaces: 1) the standard graphical user interface which is started using Java DoseApp at the command line, or by setting up a shortcut to this command (particularly when RadCon is installed on a PC) and 2) the text based interface used to generate information for the model inter-comparison exercise . This is initiated using Java BIOMASS at the command line, or an equivalent shortcut. The text based interface was developed for research purposes and is not generally available. Appendices A, B and C provide a summary of instructions on setting up RadCon. This will generally be carried out by the computer support personnel

  3. RadConEd: A Graphical Data Editor for the Radiological Consequences Model, RadCon

    International Nuclear Information System (INIS)

    This document describes the application, RadConEd, which has been designed and implemented to enable users of the RadCon system to update these parameter files. The RadCon system is written in the Java programming language, and as such provides portability across computer platforms. The software described in this report was developed in line with the portability requirements of RadCon, thus providing a uniform user interface across computer platforms and bypassing the need of using system editors. In addition a number of data integrity measures were implemented

  4. Atenuación natural en suelos contaminados con hidrocarburos

    OpenAIRE

    Lilia Corona Ramírez; Rosario Iturbe Argûelles

    2005-01-01

    Se realizó un experimento con suelo contaminado proveniente de una refinería, el cual contaba con hidrocarburos derivados de petróleo, específicamente con concentraciones elevadas de hidrocarburos poliaromáticos (HAP). El estudio consistió en preparar 7 cajones con 7 kg de suelo, cada uno con las siguientes condiciones: S1 suelo contaminado con hidrocarburos y 15% de contenido de agua. S2 suelo contaminado con hidrocarburos y adición de Nitrógeno y Fósforo (N y P) con 15% de contenido de agua...

  5. SELECTION OF BIOMASS MATERIALS PRODUCING CHAR AND ANALYSIS OF CALORIC REQUIREMENT%生物质炭化原料选择及需热量分析

    Institute of Scientific and Technical Information of China (English)

    胡威; 胡建杭; 王华; 杨丽; 邓双辉; 李娟琴

    2012-01-01

    从生物质原料的工业分析结果和木质素含量两个角度出发,分析了二者对生物质炭化的影响.对生物质炭化原料进行选择,认为木材类生物质适合作为生物质炭化的原料,可加强对树木枝条、锯末及薪炭林的炭化;为实现生物质炭化的工业化,还应设计利用烟气余热等热源来热解生物质的换热器,这项设计需知道生物质热解需热量.运用热重-差示扫描(TG-DSC)同步热分析仪对选用的木屑进行热解实验并利用DSC曲线对木屑炭化需热量进行分析.结果表明,木屑炭化终温为500℃时(初始温度为40℃),需热量为491 kJ/kg.提出DSC曲线在工业用热解换热器传热设计和校核中的应用方法.%Biomass materials for producing char had been selected after analyzing the influences of the two aspects on biomass carbonization. The two aspects are respectively the results of proximate analysis and lignin content of biomass materials. Forest biomass is suitable for biomass carbonization. The use of forest branches, sawdust and fuel forest for carbonization should been strengthened. In order to realize industrialization of biomass carbonization, heat exchanges for biomass pyrolysis utilizing residual heat of the flue should been designed. It needs to know the caloric requirement of pyrolysis. TG-DSC simultaneous thermal analyzer was used for experiments of sawdust. The analysis of caloric requirement of biomass carbonization was made. When the carbonization temperature was 500 ℃(the initial temperature was 40 ℃), caloric requirement was 491 kJ/kg. This paper also pointed out a DSC curve's application method in heat transfer design and verification of heat exchange for biomass pyrolysis.

  6. Thermal analysis of the heat recuperator of a combined cycle thermoelectric central; Analisis termico del recuperador de calor de una central termoelectrica de ciclo combinado

    Energy Technology Data Exchange (ETDEWEB)

    Romero Paredes, Hernando; Sanchez, I.; Lazcano, L. C.; Ambriz, Juan Jose; Alvarez, M. [Universidad Autonoma Metropolitana-Iztapalapa, Mexico, D. F. (Mexico); Gonzalez, O. [Comision Federal de Electricidad, Tula (Mexico)

    1996-12-31

    The thermoelectric centrals of the combined cycle type (Brayton Cycle and Rankine Cycle) present a series of opportunities to increase the efficiency of the combined cycle or of the generated power. This paper shows the methodology for the performance of energy balances in a heat recuperator (H. R.), typically employed in the combined cycle stations operating in Mexico, for the assessment of the energy harnessing in the different sections conforming a H. R. The effect of the installation of evaporative coolers and/or an absorption cooling system at the gas turbine compressor intake on the steam generation in the heat recuperator, is evaluated. This extra generation of steam is quantified for its potential use in the same absorption refrigeration system. From the assessment, it follows up that the steam generation in the H.R. is inversely proportional to the ambient temperature and that, although the increased amount of steam generated can not be harnessed in total by the steam turbine, the remaining fraction is good enough to cover the heat demand for the operation of the refrigeration system. [Espanol] Las centrales termoelectricas del tipo ciclo combinado (ciclo Brayton y ciclo Rankine) presentan un conjunto de oportunidades para incrementar la eficiencia del ciclo combinado o bien la potencia generada. En el presente trabajo se expone la metodologia para realizar los balances de energia en un recuperador de calor (R.C.) tipicamente utilizado en las Centrales de Ciclo Combinado (CCC) que operan en Mexico, para evaluar el aprovechamiento de la energia en las diferentes secciones que conforman un R.C. Se evalua el efecto que tiene la instalacion de enfriadores evaporativos y/o un sistema de enfriamiento por absorcion en la succion del compresor de la turbina de gas sobre la generacion de vapor en el recuperador de calor. Se cuantifica esta generacion extra de vapor para su posible utilizacion en el mismo sistema de refrigeracion por absorcion. De la evaluacion se

  7. Enfermedad coronaria en pacientes con psoriasis

    Directory of Open Access Journals (Sweden)

    Walter Masson

    2013-10-01

    Full Text Available Comunicaciones previas asociaron la psoriasis con la enfermedad coronaria. Desconocemos si en nuestro país o región existe dicha asociación. Se realizó un estudio transversal analizando los datos de la historia clínica electrónica de un sistema de salud de Buenos Aires. Analizamos todos los pacientes mayores de 18 años con diagnóstico de psoriasis entre el 1 de enero de 2003 y el 31 de julio de 2011 y los comparamos con un grupo control, en una relación 2:1, obtenido en forma aleatoria del mismo sistema de salud, apareados por edad y sexo. Determinamos la prevalencia de los factores de riesgo cardiovascular y de enfermedad coronaria. Analizamos la asociación entre la enfermedad coronaria y la psoriasis mediante análisis uni y multivariado. Se incluyeron 3 833 sujetos (1 286 pacientes con psoriasis y 2 547 controles. La prevalencia de hipertensión arterial (50% vs. 38%, p < 0.001, tabaquismo (25% vs. 17%, p < 0.001, diabetes (12% vs. 8%, p < 0.001 y enfermedad coronaria (4.98% vs. 3.06%, p = 0.003 fue mayor en los sujetos con psoriasis en comparación con el grupo control. Independientemente de la edad, la presencia de diabetes, hipertensión arterial o tabaquismo, hubo una asociación significativa entre la enfermedad coronaria y la psoriasis (OR 1.48, IC95% 1.04-2.11, p = 0.03. En conclusión, en esta población de Buenos Aires, los pacientes con psoriasis tuvieron una mayor prevalencia de diabetes, hipertensión arterial, tabaquismo y enfermedad coronaria. La asociación entre la psoriasis y la enfermedad coronaria fue independiente de los factores de riesgo explorados.

  8. Mincle Signaling Promotes Con A Hepatitis.

    Science.gov (United States)

    Greco, Stephanie H; Torres-Hernandez, Alejandro; Kalabin, Aleksandr; Whiteman, Clint; Rokosh, Rae; Ravirala, Sushma; Ochi, Atsuo; Gutierrez, Johana; Salyana, Muhammad Atif; Mani, Vishnu R; Nagaraj, Savitha V; Deutsch, Michael; Seifert, Lena; Daley, Donnele; Barilla, Rocky; Hundeyin, Mautin; Nikifrov, Yuriy; Tejada, Karla; Gelb, Bruce E; Katz, Steven C; Miller, George

    2016-10-01

    Con A hepatitis is regarded as a T cell-mediated model of acute liver injury. Mincle is a C-type lectin receptor that is critical in the immune response to mycobacteria and fungi but does not have a well-defined role in preclinical models of non-pathogen-mediated inflammation. Because Mincle can ligate the cell death ligand SAP130, we postulated that Mincle signaling drives intrahepatic inflammation and liver injury in Con A hepatitis. Acute liver injury was assessed in the murine Con A hepatitis model using C57BL/6, Mincle(-/-), and Dectin-1(-/-) mice. The role of C/EBPβ and hypoxia-inducible factor-1α (HIF-1α) signaling was assessed using selective inhibitors. We found that Mincle was highly expressed in hepatic innate inflammatory cells and endothelial cells in both mice and humans. Furthermore, sterile Mincle ligands and Mincle signaling intermediates were increased in the murine liver in Con A hepatitis. Most significantly, Mincle deletion or blockade protected against Con A hepatitis, whereas Mincle ligation exacerbated disease. Bone marrow chimeric and adoptive transfer experiments suggested that Mincle signaling in infiltrating myeloid cells dictates disease phenotype. Conversely, signaling via other C-type lectin receptors did not alter disease course. Mechanistically, we found that Mincle blockade decreased the NF-κβ-related signaling intermediates C/EBPβ and HIF-1α, both of which are necessary in macrophage-mediated inflammatory responses. Accordingly, Mincle deletion lowered production of nitrites in Con A hepatitis and inhibition of both C/EBPβ and HIF-1α reduced the severity of liver disease. Our work implicates a novel innate immune driver of Con A hepatitis and, more broadly, suggests a potential role for Mincle in diseases governed by sterile inflammation.

  9. Mincle Signaling Promotes Con A Hepatitis.

    Science.gov (United States)

    Greco, Stephanie H; Torres-Hernandez, Alejandro; Kalabin, Aleksandr; Whiteman, Clint; Rokosh, Rae; Ravirala, Sushma; Ochi, Atsuo; Gutierrez, Johana; Salyana, Muhammad Atif; Mani, Vishnu R; Nagaraj, Savitha V; Deutsch, Michael; Seifert, Lena; Daley, Donnele; Barilla, Rocky; Hundeyin, Mautin; Nikifrov, Yuriy; Tejada, Karla; Gelb, Bruce E; Katz, Steven C; Miller, George

    2016-10-01

    Con A hepatitis is regarded as a T cell-mediated model of acute liver injury. Mincle is a C-type lectin receptor that is critical in the immune response to mycobacteria and fungi but does not have a well-defined role in preclinical models of non-pathogen-mediated inflammation. Because Mincle can ligate the cell death ligand SAP130, we postulated that Mincle signaling drives intrahepatic inflammation and liver injury in Con A hepatitis. Acute liver injury was assessed in the murine Con A hepatitis model using C57BL/6, Mincle(-/-), and Dectin-1(-/-) mice. The role of C/EBPβ and hypoxia-inducible factor-1α (HIF-1α) signaling was assessed using selective inhibitors. We found that Mincle was highly expressed in hepatic innate inflammatory cells and endothelial cells in both mice and humans. Furthermore, sterile Mincle ligands and Mincle signaling intermediates were increased in the murine liver in Con A hepatitis. Most significantly, Mincle deletion or blockade protected against Con A hepatitis, whereas Mincle ligation exacerbated disease. Bone marrow chimeric and adoptive transfer experiments suggested that Mincle signaling in infiltrating myeloid cells dictates disease phenotype. Conversely, signaling via other C-type lectin receptors did not alter disease course. Mechanistically, we found that Mincle blockade decreased the NF-κβ-related signaling intermediates C/EBPβ and HIF-1α, both of which are necessary in macrophage-mediated inflammatory responses. Accordingly, Mincle deletion lowered production of nitrites in Con A hepatitis and inhibition of both C/EBPβ and HIF-1α reduced the severity of liver disease. Our work implicates a novel innate immune driver of Con A hepatitis and, more broadly, suggests a potential role for Mincle in diseases governed by sterile inflammation. PMID:27559045

  10. Heat transfer coefficients obtainment by means of naphthalene sublimation in air; Obtencion de coeficientes de transferencia de calor por medio de la tecnica de sublimacion de naftalina en aire

    Energy Technology Data Exchange (ETDEWEB)

    Perez Galindo, Jose Arturo; Garcia Gutierrez, Alonso [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1985-12-31

    This work describes the experimental technique for the sublimation of naphthalene in air which measures heat transfer coefficients through the use of the analogy between the transference phenomena of heat and mass. The technique used to substitute the experimental measurements of heat transfer, in which it is difficult to control the border thermal conditions, when they are dimmed by the omnipresent problem of heat conduction through the walls of the transference surfaces. Two examples are included of the application technique and its potential is outlined. [Espanol] En este trabajo se describe la tecnica experimental de la sublimacion de naftalina en aire mediante la que se miden coeficientes de transferencia de masa. Los datos asi obtenidos pueden convertirse en coeficientes de transferencia de calor a traves del uso de la analogia entre los fenomenos de transferencia de calor y masa. La tecnica se utiliza para substituir las mediciones experimentales de transferencia de calor, en las que es dificil controlar las condiciones termicas de frontera, cuando las empana el problema omnipresente de la conduccion de calor a traves de las paredes de las superficies de transferencia. Se incluyen dos ejemplos de la aplicacion de la tecnica y se destaca su potencial.

  11. Variables socionutricionales de hogares mazahuas integrados por preescolares desnutridos con madres con obesidad y sin obesidad

    Directory of Open Access Journals (Sweden)

    Conzuelo González, Viridiana Vanessa

    2009-01-01

    Full Text Available El primer objetivo fue conocer cuántos menores de cinco años con diferentes grados de desnutrición tienen una madre con sobrepeso/obesidad/ en una comunidad indígena que vive en extrema pobreza y bajo condiciones de migración masculina internacional. El segundo fue comparar tres variables socionutricionales (ingreso familiar, educación de la madre y adecuación nutrimental de la dieta diaria entre estos hogares y los hogares con desnutrición infantil y madres sin obesidad. Se realizó un estudio transversal (2006-2007, en la comunidad mazahua de San Francisco Tepeolulco, Municipio de Temascalcingo; que incluyó a 85 hogares integrados por preescolares con desnutrición inscritos al programa Oportunidades. Se determinó el estado nutrición de los preescolares con indicadores antropométricos y se obtuvo el IMC de las madres de estos infantes. Se aplicó una encuesta socionutricional, incluida el recordatorio de 24 horas, y complementado con la observación participante (cualitativa. Se encontró que 83% de las madres mazahuas presentaron sobrepeso u obesidad. El estado de nutrición de los preescolares con madres con obesidad presentó un porcentaje mayor de desnutrición (76%. En la variable género, se encontró que 54% de los niños con madres con obesidad tenía baja talla. Al relacionar el nivel educativo de la madre, esta variable resultó ser estadísticamente significativa (p=0.015, donde el analfabetismo está más relacionado con la desnutrición infantil que tienen madres de bajo y/o peso normal. La elevada prevalencia de hogares conformados con preescolares con desnutrición y madres con obesidad, es un síntoma más de la pobreza en zonas indígenas en México, con bajo índice de desarrollo humano.

  12. 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.

  13. The effect of heat and smoke on the emergence of exotic and native seedlings in a Mediterranean fire-free matorral of central Chile Efecto del calor y el humo sobre la emergencia de plántulas exóticas y nativas en un matorral mediterráneo libre de fuego en Chile central

    Directory of Open Access Journals (Sweden)

    JAVIER A FIGUEROA

    2012-03-01

    material leñoso sobre la emergencia de especies de plantas nativas y exóticas en muestras de suelo obtenidas en un matorral siempreverde de Chile central que ha estado libre de fuego por décadas, ubicado en el piedemonte occidental de la Cordillera de los Andes en San Carlos de Apoquindo. Las muestras fueron secadas y almacenadas en condiciones de laboratorio, inmediatamente después de las colectas. En cada uno de los dos transectos, diez muestras fueron aleatoriamente elegidas para la aplicación de los siguientes tratamientos: (1 golpe de calor, (2 humo producido por material vegetal, (3 calor y humo combinado, y (4 control, que corresponde a muestras que no fueron tratadas. Veinte y siete especies, que representan a 13 familias, emergieron de las muestras de suelo. Las familias más abundantes fueron Asteraceae y Poaceae. Todas las especies que emergieron fueron especies herbáceas y 18 fueron exóticas. Respecto a la hipótesis general, no hay evidencias para postular que el matorral libre de incendios tienen una menor proporción de especies exóticas y nativas con señales relacionadas al fuego que el matorral sometido a fuegos. El número promedio de especies que emergieron desde las muestras de suelo no cambiaron significativamente con respecto al control para ninguno de los tratamientos aplicados, ya sea entre las nativas y las exóticas. No obstante, importante respuestas especie específica fueron observadas. El humo y el humo-calor combinado incremetó significativamente la emergencia de la especie exótica Anthriscus caucalis. Mientras las señales relativas al humo incrementaron significativamente la emergencia de la especie exótica Avena barbata, la emergencia disminuyó en la exótica Aphanes arvensis y en la nativa Bromus berteroanus. En varias especies nuestros resultados mostraron respuestas inconsistentes a las señales relacionadas al fuego, comparadas a esas registradas en la literatura. Nosotros sugerimos que estas diferencias pueden estar

  14. Effects of caloric restriction on O-GlcNAcylation, Ca(2+) signaling, and learning impairment in the hippocampus of ob/ob mice.

    Science.gov (United States)

    Jeon, Byeong Tak; Heo, Rok Won; Jeong, Eun Ae; Yi, Chin-Ok; Lee, Jong Youl; Kim, Kyung Eun; Kim, Hwajin; Roh, Gu Seob

    2016-08-01

    Diabetes may adversely affect cognitive function and, conversely, caloric restriction (CR) increases longevity and improves memory. To shed light on the unknown underlying mechanisms involved in these observations, we examined the effects of CR on serum metabolic parameters and hippocampal protein expression in the ob/ob mice model of obesity-induced diabetes. We found that CR reduced hepatic steatosis and insulin resistance in ob/ob mice. In addition, CR increased the levels of hippocampal O-linked-N-acetylglucosamine (O-GlcNAc) and GlcNAc transferase and decreased the expression of calcium/calmodulin-dependent protein kinase II, lipocalin-2, and phosphorylated tau. Furthermore, CR lessened the learning deficits that are typically seen in ob/ob mice. These findings indicate that CR may reverse obesity-related brain glucose impairment and intracellular Ca(2+) dysfunction and relieve learning impairment associated with diabetes. PMID:27318140

  15. CONCEPCIONES ALTERNATIVAS SOBRE LOS CONCEPTOS DE ENERGÍA, CALOR Y TEMPERATURA DE LOS DOCENTES EN FORMACION DEL INSTITUTO PEDAGÓGICO EN SANTIAGO, PANAMÁ

    Directory of Open Access Journals (Sweden)

    Viterbo Rodríguez

    2012-01-01

    Full Text Available El artículo presenta los resultados de una investigación realizada en el año 2009 en el Instituto Pedagógico Superior Juan Demóstenes Arosemena. La metodología utilizada en el estudio es del tipo descriptiva cuantitativa y se utilizó una prueba de elección múltiple para recoger los datos. Cada ítem de la prueba centraba la atención en las concepciones alternativas sobre energía, calor y temperatura. Dicha prueba, después de su validación y pilotaje, fue desarrollada por 241 estudiantes de licenciatura de este Instituto. Luego de analizar las respuestas de los ítems, se obtuvo suficiente evidencia para concluir, significativamente, que los docentes en formación tienen concepciones alternativas: el 63.8% sobre el concepto de energía; 69% sobre el concepto de calor, y el 70.7% sobre el concepto de temperatura y movimiento (p=0.05. Las respuestas proporcionadas por los estudiantes demuestran que un elevado número considera que las transformaciones de energía ocurren sin ningún tipo de intercambio ni degradación de la misma. Esto revela su falta de comprensión de las leyes de la termodinámica. Las concepciones alternativas sobre el concepto de energía sugieren tres áreas o líneas principales de problemas: el concepto mismo de energía, los procesos que implican la transferencia de energía y el principio de conservación de la energía.

  16. Composição centesimal e valor calórico de alimentos de origem animal Proximate food composition and caloric value of foods from animal origen

    Directory of Open Access Journals (Sweden)

    Elizabeth A.F.S TORRES

    2000-08-01

    Full Text Available Dados sobre composição de alimentos são importantes para inúmeras atividades, porém são escassos ou inexistentes em nosso país. O presente trabalho teve como objetivo determinar o valor calórico dos alimentos de origem animal comumente usados na dieta: carne, leite e ovos a fim de compará-los com os dados das tabelas de composição centesimal mais utilizadas por profissionais da área. Observou-se que de um modo geral, ocorrem variações entre os valores das tabelas consultadas e os analisados, sendo estes menores para ovos, seguidos de laticínios, carnes suínas, carnes bovinas e aves. Salientamos portanto, a importãncia de obtenção dados sobre a composição de alimentos condizentes com diferenças regionais do Brasil, visto que a maioria das tabelas disponíveis são compilações de dados internacionais.Proximate food composition data are very important to any professionals of food science and human nutrition area. In Brazil they are rare or do not exist. The food composition of items, of animal origin, usually consumed in the diet: meat, milk e eggs, were analyzed in order to determine their caloric value. After that they were compared with the data in the Tables of Food Composition (TFC commonly used to our professionals. It was observed that there are smaller differences in the values obtained for eggs, than milk, pork, beef, chicken. Although significant difference was not detected between determined caloric values and the ones from TFC, these report should be considered to professionals that use the TFC.

  17. Immune potentiation after fractionated exposure to very low doses of ionizing radiation and/or caloric restriction in autoimmune-prone and normal C57Bl/6 mice

    International Nuclear Information System (INIS)

    Very low doses of ionizing radiation can enhance immune responsiveness and extend life span in normal mice. Total lymphoid irradiation at relatively high doses of radiation can retard autoimmune disease in genetically susceptible mice, but may impair immune function. In order to determine whether fractionated low dose exposure would enhance immune response and retard lymphadenopathy in autoimmune-prone mice, groups of C57B1/6 lpr/lpr mice were sham irradiated, exposed 5 days/week for 4 weeks to 0.04 Gy/day, or to 0.1 Gy/day. After the radiation protocol, the mice were evaluated for splenic T cell proliferative capacity, T cell subset distribution, and total spleen cell numbers. The independent and additive effect of caloric restriction was additionally assessed since this intervention has been shown to increase immune responsiveness and retard disease progression in autoimmune-prone mice. The congenic C57B1/6 +/+ immunologically normal strain was evaluated in parallel as congenic control. The results indicated that mitogen-stimulated proliferation was up-regulated in both strains of mice after exposure to 0.04 Gy/day. The proliferative capacity was additively enhanced when radiation at this dose level was combined with caloric restriction. Exposure to 0.1 Gy/day resulted in further augmentation of proliferative response in the lpr/lpr mice, but was depressive in the +/+ mice. Although the proportions of the various T cell subpopulations were altered in both strains after exposure to LDR, the specific subset alterations were different within each strain. Additional experiments were subsequently performed to assess whether the thymus is required for LDR-induced immune potentiation. Thymectomy completely abrogated the LDR effect in the +/+ mice, suggesting that thymic processing and/or trafficking is adaptively altered with LDR in this strain

  18. Intragastric pH and pressure profiles after intake of the high-caloric, high-fat meal as used for food effect studies.

    Science.gov (United States)

    Koziolek, M; Schneider, F; Grimm, M; Modeβ, Chr; Seekamp, A; Roustom, T; Siegmund, W; Weitschies, W

    2015-12-28

    The intraluminal conditions of the fed stomach are critical for drug release from solid oral dosage forms and thus, often associated with the occurrence of food effects on oral bioavailability. In this study, intragastric pH and pressure profiles present after the ingestion of the high-caloric, high-fat (964 kcal) FDA standard breakfast were investigated in 19 healthy human subjects by using the telemetric SmartPill® capsule system (26 × 13 mm). Since the gastric emptying of such large non-digestible objects is typically accomplished by the migrating motor complex phase III activity, the time required for recurrence of fasted state motility determined the gastric emptying time (GET). Following the diet recommendations of the FDA guidance on food effect studies, the mean GET of the telemetric motility capsule was 15.3 ± 4.7 h. Thus, the high caloric value of the standard breakfast impeded gastric emptying before lunch in 18 out of 19 subjects. During its gastric transit, the capsule was exposed to highly dynamic conditions in terms of pH and pressure, which were mainly dependent on further meal and liquid intake, as well as the intragastric capsule deposition behavior. Maximum pH values in the stomach were measured immediately after capsule intake. The median pH value of the 5 min period after capsule ingestion ranged between pH 3.3 and 5.3. Subsequently, the pH decreased relatively constantly and reached minimum values of pH 0-1 after approximately 4 h. The maximum pressure within the stomach amounted to 293 ± 109 mbar and was clearly higher than the maximum pressure measured at the ileocaecal junction (60 ± 35 mbar). The physiological data on the intraluminal conditions within the fed stomach generated in this study will hopefully contribute to a better understanding of food effects on oral drug product performance.

  19. Simulation of the heat transfer of a irradiated fuel storage container with code CFD STAR- CCM+; Simulacion de la transferencia de calor de un contenedor de almacenamiento de combustible irradiado con el codigo CFD STAR-CCM+

    Energy Technology Data Exchange (ETDEWEB)

    Barrera matalla, J. E.; Hernandez Gomez, J.; Riverala Gurruchaga, J.

    2012-07-01

    Irradiated fuel has become an object of interest in the industry by the importance of ensuring its safety during long periods of storage time. New containers, stores, methods and codes will be used to ensure a suitable cooling and residual heat removal, and secure the safety of fuel elements in dry storage. The codes CFD (Computational Fluid Dynamics) have great potential to help in design of containers and stores, improving thermal-hydraulic performance and the extraction of heat generated.

  20. Heat transfer and phenomenology in severe accidents in spent fuel pools with MAAP5; Transmision de calor y fenomenologia en accidentes severes en piscinas de combustible gastado con MAAP5

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz, J. A.; Gil, E.; Uruburu, A.; Rey, P.

    2013-07-01

    The code Thermo-hydraulic MAAP5 includes in their latest versions a module that allows you to analyze the evolution of an accident occurring in the pool of spent fuel from a nuclear power plant in their latest versions. This module is a preliminary version and there is interest from stations and reference centres in Spain to know in depth its capabilities.