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Sample records for acondicionamiento con calor

  1. 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.

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

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    Gabriel Eduardo Rocha Camino

    1985-09-01

    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.

  3. Productos «Celotex» para acondicionamientos Acústicos

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    Editorial, Equipo

    1958-02-01

    Full Text Available Not availableBajo la denominación general «Celotex», que es un nombre registrado, la Casa Americana The Celotex Corporation, cuyo domicilio social es 120 South, La Salle Street, Chicago J. lllinois, fabrica diversos materiales para fines de acondicionamiento acústico elaborados, según los tipos de que se trate, con fibra de caña de azúcar, lanas minerales, acero, amianto, etc., perforados o no y de acuerdo con el efecto estético y acústico que se desee obtener.

  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

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    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. Actualidad y perspectivas de una bomba de calor de expansión directa con energía solar

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    Gorozabel-Chata, Francis-B.; Carbonell-Morales, Tania

    2016-01-01

    La bomba de calor de expansión directa con asistencia de energía solar se utiliza en el modo de calefacción para diversas aplicaciones entre las que podemos citar, calentamiento de agua, calentamiento de aire para climatizar edificios, desalinización de agua, secado solar entre otras. El presente trabajo revisa las principales investigaciones sobre esta tecnología enfocando sus aplicaciones para el calentamiento de agua, para lograr este objetivo se describen en detalle la configuración básic...

  6. Refrigeración local de vehículos con calor excedente

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    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...

  7. 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

  8. 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.

  9. Calore e termodinamica

    CERN Document Server

    Zemansky, Mark W

    1970-01-01

    Temperatura ; sistemi termodinamici semplici ; lavoro ; il calore e il primo principio ; gas ideali ; teoria cinetica dei gas ideali ; il secondo principio della termodinamica ; reversibilità e temperatura Kelvin ; entropia ; meccanica statistica sostanze pure ; transizioni di fase, elio liquido ed elio solido ; sistemi particolari ; paramagnetismo, fisica delle basse temperature, temperature negative e terzo principio ; superfluidità e superconduttività ; equilibrio chimico ; reazioni con gas ideali ; sistemi eterogenei.

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

    OpenAIRE

    Sioli Durán, José Manuel

    2015-01-01

    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...

  11. 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

  12. Validación de un ciclo de despirogenización por calor seco con el empleo del ensayo del lisado de amebocitos de limulus

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    Rolando Perdomo Morales

    2003-12-01

    Full Text Available Para el cumplimiento de las buenas prácticas de laboratorio y de fabricación de parenterales, una de las exigencias es la validación de los ciclos de despirogenización que se emplean. En el presente trabajo se describe la validación de un ciclo de despirogenización por calor seco en un horno de convección. En la primera etapa se estudiaron características físicas del equipo como el tiempo requerido para alcanzar la temperatura establecida, su distribución, estabilidad, y la influencia de la carga en el patrón de calentamiento. Considerando los resultados de esta fase se estableció un proceso total de 7 h a 180 ºC. La segunda etapa consistió en la determinación del grado de despirogenización retando el proceso con bioindicadores de endotoxinas. La concentración de endotoxinas en los bioindicadores control y sometidos al proceso de despirogenización se cuantificó con el empleo del ensayo del lisado de amebocitos de limulus método de gelificación. La diferencia entre el contenido de endotoxinas en el control y los tratamientos fue de 2 400 U de endotoxinas, por lo que el proceso rindió una reducción logarítmica mínima de 4,6 log, la cual es mayor que el límite de 3 log establecido por la Farmacopea de los Estados Unidos.To fullfill the good laboratory and parenteral drugs manufacturing practices, one of the demands is the validation of the depyrogenation cycles that are used. In this paper, it is described the validation of a depyrogenation cycle by dry heat in a convection oven. The physical features of the equipment, such as the time required to reach the established temperature, its distribution, stability, and the influence of the charge on the heating pattern, were studied in the first stage. Taking into account the results of this phase, it was established a total process of 7 h at 180 °C. The second stage consisted in the determination of the degreee of depyrogenation, challenging the process with endotoxin

  13. 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

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    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.

  14. 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.

  15. 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

  16. Estudio experimental de la conducción del calor en el maquinado de materiales endurecidos con altas velocidades de corte. // Experimental study of heat conduction in mechanization with high cutting speeds of hardened materials.

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    L. Cardoso Brandão

    2006-01-01

    Full Text Available El trabajo trata del estudio teórico-experimental de la conducción del calor en los materiales endurecidos, usados para laproducción de moldes y matrices, al maquinarlos con altas-velocidades del corte. Los materiales utilizados son los acerosAISI P20 y AISI D2. Los ensayos se realizaron con fresas de punta esférica (Ball Nose con revestimiento (TiAlN y lasprobetas para los ensayos tienen la forma de una ¼ parte de un tubo de 28 mm de diámetro con una longitud de 100 mm.Las pruebas realizadas demuestran la variación de la temperatura en función de los diferentes sistemas de refrigeración. Seutilizo aire comprimido y aire comprimido frío, comparándose las temperaturas de las probetas con el sistema sinrefrigeración de ningún tipo. Fueron también evaluadas las deformaciones sufridas por la superficie maquinada, debido alas variaciones de temperatura teniendo en cuenta la influencia de los sistemas de refrigeración empleados.Palabras claves: Temperatura; conducción del calor; alta velocidad de corte, moldes y matrices._________________________________________________________________________Abstract.This paper deals with the theoretical-experimental study of heat conduction in hardened materials for the production ofmolds and dies using high speed cutting. The employed materials were the AISI P20 and AISI D2 steels, being the testscarried out with (TiAlN coated ball nose in a work piece with the shape of a 1/4 tube with 28 mm diameter and 100 mmlength. This investigation demonstrates the variation of temperature as a function of different cooling systems, that is,compressed air and compressed cold air. Possible geometric deformation of the machined surfaces due to these variationsin temperature for distinct cooling systems was also evaluated.Keywords: Temperature, heat exchange; high cutting speed, dies.

  17. 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.

  18. 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

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    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

  19. TEMPERATURE AND HEAT FLOW WHEN TAPPING OF THE HARDENED STEEL USING DIFFERENT COOLING SYSTEMS TEMPERATURA Y FLUJO DE CALOR AL ROSCAR CON MACHOS ACERO ENDURECIDO UTILIZANDO DIVERSOS SISTEMAS DE LUBRICACIÓN

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    Lincoln Cardoso Brandão

    2009-08-01

    la probeta de prueba a 3.0, 7.0 y 11.0 mm desde la entrada del roscado. Se hacen dos réplicas del registro de la temperatura para cada condición de corte ensayada. Se utilizan un modelo teórico-analítico de conducción de calor para evaluar la temperatura en la interfase de la probeta de prueba, determinar el flujo de calor y el coeficiente de convección. El menor incremento de la temperatura y del calor se observa al utilizar el método lubricante en grandes cantidades, seguido por el de MQF, al comparar con la condición en seco. El efecto es directamente proporcional a la cantidad de lubricante aplicado, siendo también significativo con el sistema MQF al compararlo con el corte en seco.

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

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    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.

  1. Mecanismos efectores de las células fagocíticas estimuladas in vitro con S. Pyogenes vivo e inactivado por calor

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    Agustín C. Möhlinger

    2013-01-01

    Full Text Available Introducción: Los estreptococos del Grupo A son patógenos frecuentes en los seres humanos, responsables de diversas infecciones. Diferentes estudios  han demostrado mecanismos involucrados en las defensas del huésped frente a la infección por S. pyogenes. S. pyogenes desencadena una respuesta inmune importante con la consiguiente participación de diversos tipos celulares, como polimorfonucleares neutrófilos, macrófagos y células dendríticas, así como las subpoblaciones TH1 y Th2. El presente estudio pretende describir la respuesta de Polimorfonucleares (PMNs y Mononucleares (MNs de sujetos normales frente al S. pyogenes vivo (Spv e inactivado (Spi. Materiales y Métodos: Se separaron los PMNs y MNs de sangre periférica de 48 sujetos donantes sanos. Se incubaron en tubos separados las suspensiones de PMN y MNs en medio RPMI 1640 con 5l las suspensiones de S. pyogenes vivo (Spyv e inactivado (Spyi. Se evaluaron nitritos por el Método de Griess y TNFα por ELISA ( R& D Systems. En PMNs y MNs se determinó el Estallido Respiratorio (ER por Citometría de Flujo. Resultados: Estallido Respiratorio. R(x± E.E.: PMNs est. c/Spv: 2,50±0,478; PMNs est. c/Spi: 1,921±0,275; PMNs Basal: 1,282±0,105. P=0,0483. MNs est. c/Spv: 2,56±0,51; MNs est. c/Spi: 1,92±0,27; MNs Basal: 1,21±0,10. Spv vs Spi P>0,05 ns; Spv vs basal P0,05ns. Niveles Nitritos(x± E.E. MNs est c/ Spv, Spi y Basal: 40,75±5,94; 57,85±8,79; 13,28±1,13. MNs Basal vs MNs Spv P0,05 NS. Niveles de TNFα(x± E.E.: PMNs est c/ Spv, Spi y Basal: 223,54±21,49; 202,78±37,37; 100,82±3,23. PMNs Spv vs Spi P>0,05ns; PMNs Spv vs Basal P0,05 NS; Spv vs Basal P<0,01; Spi vs Basal P<0,05. Discusión: Se determinó que el S. pyogenes tanto vivo como inactivado tiene capacidad para estimular a las células fagocíticas, activando su capacidad oxidativa através del Estallido Respiratorio, la producción de nitritos y la de TNF alfa en sobrenadante de cultivo Celular incrementado su

  2. MECANISMOS EFECTORES DE LAS CÉLULAS FAGOCÍTICAS ESTIMULADAS IN VITRO CON S. PYOGENES VIVO E INACTIVADO POR CALOR

    Directory of Open Access Journals (Sweden)

    Agustín C. Möhlinger

    2012-01-01

    Full Text Available Objetivos: Los estreptococos del Grupo A son patógenos frecuentes en los seres humanos, responsables de diversas infecciones. Diferentes estudios han demostrado mecanismos involucrados en las defensas del huésped frente a la infección por S. pyogenes. S. pyogenes desencadena una respuesta inmune importante con la consiguiente participación de diversos tipos celulares, como polimorfonucleares neutrófilos, macrófagos y células dendríticas, así como las subpoblaciones TH1 y Th2. El objeto del presente estudio fue examinar la respuesta de Polimorfonucleares (PMNs y Mononucleares (MNs de sujetos normales frente al S. pyogenes vivo (Spv e inactivado(Spi. Métodos: Se separaron los PMNs y MNs de sangre periférica de 48 sujetos donantes sanos. Se incubaron en tubos separados las suspensiones de PMN y MNs en en medio RPMI 1640 con 5l de las suspensiones de S. pyogenes vivo (Spyv e inactivado (Spyi . En el sobrenadante de cultivo de MN y PMN, se evaluaron nitritos (Método de Griess y TNFα [ELISA ;R& D Systems]. En dichas células se determinó el Estallido Respiratorio (ER por Citometría de Flujo. Resultados: Estallido Respiratorio. R(X± E.E.: PMNs est. c/Spv: 2,50±0,478; PMNs est. c/Spi: 1,921±0,275; PMNs Basal: 1,282±0,105. P=0,0483. MNs est. c/Spv: 2,56±0,51; MNs est. c/Spi: 1,92±0,27; MNs Basal: 1,21±0,10. Spv vs Spi P>0,05 ns; Spv vs basal P0,05ns. Niveles Nitritos(x± E.E. MNs est c/ Spv, Spi y Basal: 40,75±5,94; 57,85±8,79; 13,28±1,13. MNs Basal vs MNs Spv P0,05 NS. Niveles de TNFα(x± E.E.: PMNs est c/ Spv, Spi y Basal: 223,54±21,49; 202,78±37,37; 100,82±3,23. PMNs Spv vs Spi P>0,05ns; PMNs Spv vs Basal P0,05 NS; Spv vs Basal P<0,01; Spi vs Basal P<0,05. Conclusiones: Se determinó que el S. pyogenes tanto vivo como inactivado tiene capacidad para estimular a las células fagocíticas, activando su capacidad oxidativa através del Estallido Respiratorio, la producción de nitritos y la de TNF alfa en sobrenadante de

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

    Directory of Open Access Journals (Sweden)

    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.

  4. El clima de las ciudades: isla de calor de Salamanca

    OpenAIRE

    Mª Salud Alonso García; Mª del Rosario Fidalgo Martínez; José Luis Labajo Salazar

    2004-01-01

    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 situ...

  5. 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.

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

    Directory of Open Access Journals (Sweden)

    Cinthya Campos Salazar

    2001-12-01

    Full Text Available 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 durante 16 semanas. Se aplicó un pretest y un postest de movilidad articular para medir la movilidad global de las caderas (flexión, abducción, aducción, rotación interna y externa. Las variables independientes fueron lado izquierdo y derecho vs. grupos de tratamiento. Los resultados indicaron lo siguiente: el grupo control no varío la movilidad articular en las mediciones de flexión, rotación interna y externa (p>0.05 mientras que para la mediciones de abducción y aducción disminuyó significativamente (p<0.05. En cuanto a los grupos de tratamiento, el grupo que realizó el programa combinado de hidroquinesia y acondicionamiento físico aumentó significativamente (p<0.05 la movilidad articular a nivel de flexión, abducción y aducción, en tanto el grupo que realizó el programa de acondicionamiento físico solamente, mejoró significativamente (p<0.05 en flexión, abducción, aducción, rotación interna como externa. En conclusión se recomienda la práctica de actividad física tanto en el agua como fuera de ella, pues mejora los rangos de movilidad articular en cadera, a nivel global en personas adultas mayores.

  7. 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

  8. 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 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 presenta sus valores más altos en primavera. Realizando un estudio estadístico de la evolución anual de la isla de calor nocturna en Salamanca, podemos definir isla de calor débil si su intensidad es inferior a 2 oC, moderada si se encuentra entre 2 oC y 4 oC e intensa si supera los 4 oC.

  9. Acondicionamiento de reproductores, desove y cultivo larval de Graus nigra (Philippi, 1887 (Kyphosidae: Girellinae Broodstock conditioning, spawning and larval culture of Graus nigra (Philippi, 1887 (Kyphosidae: Girellinae

    Directory of Open Access Journals (Sweden)

    Avelino Muñoz

    2012-09-01

    Full Text Available Se describen resultados sobre acondicionamiento reproductivo, desove y cultivo larval de Graus nigra ("vieja negra", "mulata". Peces adultos silvestres se recolectaron y se utilizaron como reproductores, los que al final del período de acondicionamiento alcanzaron el estado de maduración gonadal y desovaron en forma natural y espontánea. Los huevos fueron recolectados y después de 36 h de incubación eclosionaron, con una tasa de eclosión promedio de 60%. Las larvas recién eclosionadas midieron 2,9 ± 0,23 mm y alcanzaron el día 50 post-eclosión (PE una longitud total de 12,6 ± 0,37 mm. La sobrevivencia larval posterior a la eclosión fue entre 50,9 y 79,1% y al día 30 PE fue de 12,1%. El cultivo larval se desarrolló en estanques con suministro de agua de mar filtrada y esterilizada. Después de la reabsorción del saco vitelino se produjo el desarrollo del tracto digestivo y las larvas se alimentaron con dieta viva enriquecida con emulsión de ácidos grasos altamente insaturados. A los 35 días de cultivo se ofreció alimento artificial a las larvas cuyo tamano fue aumentando progresivamente a medida que progresó su desarrollo ontogénico. Se describe la evolución anatómica de las larvas y las relaciones morfométricas que representan su desarrollo; se caracteriza el patrón de crecimiento de las larvas hasta los 50 días post-eclosión y se discuten aspectos relacionados con la sobrevivencia larval y la introducción de mejoras para optimizar la producción de larvas y juveniles.In this study results related to reproductive conditioning, spawning and larval culture of Graus nigra ("vieja negra", "mulata" are given. Wild adult fishes were collected and used as brooders which at the end of the conditioning period reached gonadal maturation state and spawned naturally and spontaneously. Eggs were collected and after 36 hours of incubation they hatched at average rate of 60%. The hatched larvae measured 2.9 ± 0.23 mm and at day 50

  10. 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.

  11. Eficacia de dos técnicas de acondicionamiento para la atención odontológica de niños de 6 a 10 años de edad de una escuela pública de Quito-Ecuador

    Directory of Open Access Journals (Sweden)

    Susana Loayza

    2017-07-01

    Full Text Available Este estudio compara dos técnicas de acondicionamiento para atención infantil, que son; la técnica de decir, mostrar y hacer, la técnica de distracción visual-auditiva; para de esta manera poder identificar el grado de aceptación y colaboración de los niños al tratamiento preventivo con sellantes. Se realizaron dos citas para la atención: en la primera se llenó la historia clínica y la profilaxis, en la segunda se realizó un sellante. Se utilizó la escala de Frankl para poder valorar el comportamiento antes y después de la aplicación de un sellante, Como resultado, las dos técnicas demostraron tener la misma efectividad, pero, en casos donde niños llegan con experiencias negativas es mucho más efectiva la técnica decir, mostrar y hacer. Se concluye que las técnicas de acondicionamiento decir, mostrar y hacer, más la técnica de distracción visual- auditiva son eficaces para que los niños acepten de mejor manera el procedimiento preventivo con la colocación de sellantes.

  12. Diseño de la instalación de climatización y agua caliente de un edificio residencial con bomba de calor aire-agua y energía solar térmica y fotovoltaica

    OpenAIRE

    Jiménez López, Laura

    2010-01-01

    El proyecto que a continuación se relata tiene objetivo evaluar y calificar energéticamente una vivienda basada en un sistema energético todo eléctrico. La tecnología de climatización y producción de Agua caliente utilizada será la Bomba de Calor aire-agua. Se incorporará la aportación de energía solar térmica y energía fotovoltaica. La realización del proyecto contará con la integración de ambas tecnologías en el edificio estudiado. El sistema de climatización y producción de Agua c...

  13. 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

  14. The GEANT-CALOR interface

    International Nuclear Information System (INIS)

    Zeitnitz, C.; Gabriel, T.A.

    1994-01-01

    The simulation of large scale high energy physics experiments is based mainly on the GEANT package. In the current version 3.15 the simulation of hadronic interacting particles is based on GHEISHA or FLUKA. Both programs miss an accurate simulation of the interaction of low energy neutrons (E kin < 20 MeV) with the materials of the detector. The CALOR89 program package contains a low energetic neutron code. An interface between the CALOR program parts and the GEANT package has been developed

  15. Hombre, calor y aislamiento

    Directory of Open Access Journals (Sweden)

    Neutra, Richard J.

    1961-11-01

    Full Text Available Con los nuevos tipos estructurales y con los adelantos de las ciencias biológicas en lo que se refiere a los procesos orgánicos, mis ideas sobre aislamiento, y las de casi todos los demás arquitectos y constructores, han sufrido una evolución interesantísima en los últimos veinticinco años. Y me complace subrayar que los que, como yo, estudiamos el decorado humano, podemos hacer mucho en beneficio de nuestros clientes. No hace aún mucho tiempo toda la protección de una casa contra el peligro de transferencia térmica se confiaba exclusivamente a muros y cubiertas no aislantes. Los propietarios se limitaban a culpar al tiempo de su falta de confort. Pero esta falta de comodidad en cuanto a calefacción no era la única consecuencia; tras ella aparecían daños de efectos duraderos y patológicos.

  16. Sistema de enfriamiento con desecante para reducir consumo de energía en restaurante caso de estudio; Desiccant cooling system to decrease energy consumption in Restaurant study case

    Directory of Open Access Journals (Sweden)

    Tania Carbonell Morales

    2015-12-01

    Full Text Available Este artículo mostró la posibilidad de emplear un sistema de enfriamiento con rueda desecante para el tratamiento del aire de las diferentes áreas del Restaurante caso de estudio, instalación alta consumidora de energía, de ahí la necesidad de estudiar nuevas alternativas para el acondicionamiento de aire que permitan el control de la humedad y el ahorro de energía. El análisis bibliográfico realizado mostró que actualmente los sistemas de enfriamiento con desecante están siendo estudiados y empleados como una alternativa para el ahorro de energía y el cuidado del medioambiente en el campo del tratamiento del aire. Se propuso un sistema compuesto fundamentalmente por una rueda desecante de gel de sílice, una rueda conservadora de energía y un intercambiador de calor. Con el nuevo sistema de enfriamiento la demanda de energía eléctrica disminuye previéndose ahorros del orden de 1 1802 CUC anualmente solo por concepto de consumo de energía eléctrica.In this paper the possibility of using a cooling system with a desiccant wheel for air treatment of different areas of the case study restaurant is shown. This facility is classified as high consumer of energy, making it necessaryto study new alternatives for air conditioning allowing humidity control and energy saving. The literature review conducted on cooling systems with desiccant wheel technology was currently being studied and used as analternative to saving energy and protecting the environment in the field of air treatment. The desiccant cooling system proposed is fundamentally for a desiccant wheel of silica gel, an energy conservative wheel and a heatexchanger. With the new cooling system electricity demand decreases and significant savings of about 1 1802 CUC are forecasted only in annual electricity consumption.

  17. Proyecto de mejora y acondicionamiento como apeadero multimodal de la parcela ARI-T03 y de varios viales en el municipio de San Fernando (Cádiz)

    OpenAIRE

    Díaz Ramos, Jesús

    2014-01-01

    El objeto del presente Proyecto es definir las obras necesarias para la correcta ejecución de las obras de mejora y acondicionamiento como apeadero multimodal de la parcela ARI-T03 y de varios viales, en el municipio de San Fernando (Cádiz).

  18. 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

  19. DESARROLLOS INSTRUMENTALES EN MICROCALORIMETRIA DE CONDUCCIÓN DE CALOR

    Directory of Open Access Journals (Sweden)

    Liliana Giraldo G.

    2010-09-01

    Full Text Available Se presentan aspectos generales de la microcalorimetría de conducción de calor. Se describe el diseño y la operación de microcalorímetros de conducción de calor estático y de flujo construidos en este laboratorio, los cuales fueron calibrados eléctrica y químicamente. Estos equipos se emplean en la caracterización de sólidos porosos por la técnica de calorimetría de inmersión y en la determinación de entalpias de transferencia de solutos; su uso se ilustra con algunos resultados típicos. Se mencionan además otras aplicaciones que se dan actualmente a estos aparatos.

  20. 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

  1. Eficacia de dos técnicas de acondicionamiento para la atención odontológica de niños de 6 a 10 años de edad de una escuela pública de Quito-Ecuador

    OpenAIRE

    Susana Loayza; Sofía Azanza

    2017-01-01

    Este estudio compara dos técnicas de acondicionamiento para atención infantil, que son; la técnica de decir, mostrar y hacer, la técnica de distracción visual-auditiva; para de esta manera poder identificar el grado de aceptación y colaboración de los niños al tratamiento preventivo con sellantes. Se realizaron dos citas para la atención: en la primera se llenó la historia clínica y la profilaxis, en la segunda se realizó un sellante. Se utilizó la escala de Frankl para poder valorar el compo...

  2. 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…

  3. 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.

  4. Intake of calorically sweetened beverages and obesity

    DEFF Research Database (Denmark)

    Olsen, N J; Heitmann, B L

    2009-01-01

    The prevalence of obesity has increased in the past 30 years, and at the same time a steep increase in consumption of soft drinks has been seen. This paper reviews the literature for studies on associations between intake of calorically sweetened beverages and obesity, relative to adjustment...... studies were identified. The majority of the prospective studies found positive associations between intake of calorically sweetened beverages and obesity. Three experimental studies found positive effects of calorically sweetened beverages and subsequent changes in body fat. Two experimental studies did...... not find effects. Eight prospective studies adjusted for energy intake. Seven of these studies reported associations that were essentially similar before and after energy adjustment. In conclusion, a high intake of calorically sweetened beverages can be regarded as a determinant for obesity. However...

  5. Fasting or caloric restriction for healthy aging.

    Science.gov (United States)

    Anton, Stephen; Leeuwenburgh, Christiaan

    2013-10-01

    Aging is associated with a host of biological changes that contribute to a progressive decline in cognitive and physical function, ultimately leading to a loss of independence, and increased risk of mortality. To date, prolonged caloric restriction (i.e., a reduction in caloric intake without malnutrition) is the only non-genetic intervention that has consistently been found to extend both mean and maximal life span across a variety of species. Most individuals have difficulty sustaining prolonged caloric restriction, which has led to a search for alternative approaches that can produce similar to benefits as caloric restriction. A growing body of evidence indicates that fasting periods and intermittent fasting regimens in particular can trigger similar biological pathways as caloric restriction. For this reason, there is increasing scientific interest in further exploring the biological and metabolic effects of intermittent fasting periods, as well as whether long-term compliance may be improved by this type of dietary approach. This special will highlight the latest scientific findings related to the effects of both caloric restriction and intermittent fasting across various species including yeast, fruit flies, worms, rodents, primates, and humans. A specific emphasis is placed on translational research with findings from basic bench to bedside reviewed and practical clinical implications discussed. Copyright © 2013 Elsevier Inc. All rights reserved.

  6. 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.

  7. 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.

  8. Asymmetry dependence of the nuclear caloric curve

    International Nuclear Information System (INIS)

    McIntosh, A.B.; Bonasera, A.; Cammarata, P.; Hagel, K.; Heilborn, L.; Kohley, Z.; Mabiala, J.; May, L.W.; Marini, P.; Raphelt, A.; Souliotis, G.A.; Wuenschel, S.; Zarrella, A.; Yennello, S.J.

    2013-01-01

    A basic feature of the nuclear equation of state is not yet understood: the dependence of the nuclear caloric curve on the neutron–proton asymmetry. Predictions of theoretical models differ on the magnitude and even the sign of this dependence. In this work, the nuclear caloric curve is examined for fully reconstructed quasi-projectiles around mass A=50. The caloric curve extracted with the momentum quadrupole fluctuation thermometer shows that the temperature varies linearly with quasi-projectile asymmetry (N−Z)/A . An increase in asymmetry of 0.15 units corresponds to a decrease in temperature on the order of 1 MeV. These results also highlight the importance of a full quasi-projectile reconstruction in the study of thermodynamic properties of hot nuclei

  9. 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 %.

  10. 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.

  11. Sistema de enfriamiento con desecante para reducir consumo de energía en restaurante caso de estudio; Desiccant cooling system to decrease energy consumption in Restaurant study case

    Directory of Open Access Journals (Sweden)

    Tania – Carbonell Morales

    2016-02-01

    Full Text Available Este artículo mostró la posibilidad de emplear un sistema de enfriamiento con rueda desecante para el tratamiento del aire de las diferentes áreas del Restaurante caso de estudio, instalación alta consumidora de energía, de ahí la necesidad de es tudiar nuevas alternativas para el acondicionamiento de aire que permitan el control de la humedad y el ahorro de energía. El análisis bibliográfico realizado mostró que actualmente los sistemas de enfriamiento con desecante están siendo estudia dos y empleados como una alternativa para el ahorro de energía y el cuidado del medioambiente en el campo del tratamiento del aire. Se propuso un sistema compuesto fundamentalmente por una rueda desecante de gel de sílice, una rueda conservadora de energía y un intercambiador de calor. Con el nuevo sistema de enfriamiento la demanda de energía eléctrica disminuye previéndose ahorros del orden de 11802 CUC anualmente solo por concepto de consumo de energía eléctrica. In this paper the possibility of using a cooling syst em with a desiccant wheel for air treatment of different areas of the case study restaurant is shown. This facility is classified as high consumer of energy, making it necessary to study new alternatives for air conditioning allowing humidity control and energy saving. The literature review conducted on cooling systems with desiccant wheel technology was currently being studied and used as an alternative to saving energy and protecting the environment in the field of air treatment. The desiccant cooling system proposed is fundamentally for a desiccant wheel of silica gel, an energy conservative wheel and a heat exchanger. With the new cooling system electricit y demand decreases and significant savings of about 11802 CUC are forecasted only in annual electricity consumption

  12. Overweight and aerobic fitness in children in the United States/Mexico border region El sobrepeso y el acondicionamiento aeróbico en niños de la frontera mexicanoestadounidense

    Directory of Open Access Journals (Sweden)

    Karen J. Coleman

    2004-04-01

    overweight than were non-Hispanic white children throughout the United States. In addition, the children in El Paso were less aerobically fit than were non-Hispanic white children and than were other Mexican-American children in the United States. These results clearly show that efforts should be made in the border regions of both Mexico and the United States to develop physical activity and nutrition programs to help stem rising rates of overweight.OBJETIVO: Estudiar el sobrepeso y el acondicionamiento aeróbico en niños de tercero y cuarto grado de primaria en una ciudad de Estados Unidos de América (El Paso, Texas y una ciudad de México (Chihuahua, Chihuahua, ambas situadas en la frontera entre esos dos países o cerca de ella, así como comparar los resultados observados en esas dos ciudades con resultados obtenidos anteriormente en otras muestras infantiles en Estados Unidos. MÉTODOS: Seguimos a un grupo de niños en El Paso (427 varones y 385 niñas, 93% de los cuales eran de ascendencia mexicana que cursaban el tercero o cuarto grado de primaria y evaluamos cambios en el índice de masa corporal (IMC. En la ciudad de Chihuahua medimos el IMC en una muestra transversal de niños de tercer grado (221 varones y 237 niñas y de cuarto grado (268 varones y 215 niñas. A todos los niños estudiados en ambas ciudades se les tomaron mediciones de IMC y del pliegue cutáneo del tríceps. El IMC se usó para estimar el riesgo de sobrepeso (un IMC igual o mayor al del percentil 85 para la edad y el sexo y para detectar la presencia de sobrepeso (un IMC igual o mayor al del percentil 95 para la edad y el sexo. La distancia que los niños en El Paso corrieron en nueve minutos se usó para evaluar su grado de acondicionamiento aeróbico (el cual no se midió en los niños de Chichuaua. En El Paso los datos se recolectaron en 1999, 2000 y 2001 y en Chichuahua, en 2000 y 2001. RESULTADOS: En los varones de El Paso se observó un aumento significativo de 22 a 28% en la frecuencia

  13. Isla de calor y ocupación espacial urbana en San Juan, Argentina: análisis evolutivo

    OpenAIRE

    Papparelli, Alberto; Kurbán, Alejandra; Cúnsulo, Mario

    2013-01-01

    En este articulo se presentan resultados finales de un proyecto de investigacion 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 modificacion de la isla de calor urbana en un periodo de quince anos (1995-2010) y la correlacion de esta con la ocupacion del area urbana del Gran San Juan (GSJ), localizada en la diagonal arida de...

  14. 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 ...

  15. Estudio y optimización de los sistemas de intercambio de calor en generación termoeléctrica aplicada al aprovechamiento del calor residual

    OpenAIRE

    Aranguren Garacochea, Patricia

    2015-01-01

    La presente tesis doctoral estudia el aprovechamiento del calor residual mediante generación termoeléctrica para la obtención de potencia eléctrica generada gracias al efecto Seebeck. Dos son las aproximaciones empleadas, la simulación computacional, empleando variables obtenidas experimentalmente y la experimentación de escenarios reales. Ambas dos han obtenido valores muy prometedores para la generación eléctrica a través de los gases residuales. Con el desarrollo de esta tesis doctoral,...

  16. 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.

  17. La Isla de calor en la ciudad de Lloret de Mar

    OpenAIRE

    Moreno García, María del Carmen; Serra Pardo, Juan Antonio

    2017-01-01

    Este artículo muestra el resultado de un trabajo de investigación sobre el fenómeno de la isla de calor en la ciudad de Lloret de Mar, donde se evidencia la existencia del fenómeno y se caracteriza. Utilizando el método de los transectos se han realizado mediciones de temperatura en cuatro campañas anuales entre julio del 2010 y marzo de 2014, durante el verano e invierno. El análisis de los 11.360 valores térmicos recopilados muestra una isla de calor urbana con una intensidad media de 3,3ºC...

  18. 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.

  19. 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)

    1997-12-31

    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.

  20. Transferencia de calor durante la congelación, el almacenamiento y la descongelación de alimentos

    OpenAIRE

    Salvadori, Viviana Olga

    1994-01-01

    En el presente trabajo se estudian distintos aspectos relacionados con la congelación y el almacenamiento de productos congelados, con los siguientes objetivos: - Optimizar el diseño de sistemas para la congelación o almacenamiento de alimentos a través de un mejor conocimiento de los fenómenos de transferencia de calor que tienen lugar en los mismos. Esto involucra un adecuado dimensionamiento de los equipos con el consiguiente ahorro en los costos de inversión. - Desar...

  1. 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.

  2. Use of non-caloric edulcorants in children

    OpenAIRE

    Calzada León Raúl; Altamirano Bustamante Nelly

    2014-01-01

    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.

  3. 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.

  4. 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.

  5. 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

  6. Nutrigenetics and nutrigenomics of caloric restriction.

    Science.gov (United States)

    Abete, Itziar; Navas-Carretero, Santiago; Marti, Amelia; Martinez, J Alfredo

    2012-01-01

    Obesity is a complex disease resulting from a chronic and long-term positive energy balance in which both genetic and environmental factors are involved. Weight-reduction methods are mainly focused on dietary changes and increased physical activity. However, responses to nutritional intervention programs show a wide range of interindividual variation, which is importantly influenced by genetic determinants. In this sense, subjects carrying several obesity-related single-nucleotide polymorphisms (SNPs) show differences in the response to calorie-restriction programs. Furthermore, there is evidence indicating that dietary components not only fuel the body but also participate in the modulation of gene expression. Thus, the expression pattern and nutritional regulation of several obesity-related genes have been studied, as well as those that are differentially expressed by caloric restriction. The responses to caloric restriction linked to the presence of SNPs in obesity-related genes are reviewed in this chapter. Also, the influence of energy restriction on gene expression pattern in different tissues is addressed. Copyright © 2012 Elsevier Inc. All rights reserved.

  7. Conceptos esenciales de la transmisión de calor en una edificación

    Directory of Open Access Journals (Sweden)

    Safranez, Carlos

    1981-05-01

    Full Text Available Dirigiéndose esta publicación al técnico del ramo de la Construcción, poco familiarizado con los problemas de aislamiento térmico, se presenta una breve exposición de los conceptos esenciales de la transmisión de calor en una edificación. Se exponen ejemplos del cálculo de la resistencia térmica y de la curva de temperatura de una cubierta plana y de un sótano. Se analiza la repercusión del aislamiento térmico sobre el consumo de energía con tiempo frío y tiempo caluroso. Sobre la posibilidad de producirse condensaciones, y sobre la temperatura a que estará expuesta la membrana impermeabilizante de un sótano, debido a la calefacción, con el fin de que no sobrepase los límites fijados. Finalmente, se dan a conocer dos ábacos para la determinación del coeficiente K de la transmisión de calor y de la resistencia térmica R, de distintos tipos de aislamiento.

  8. 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.

  9. 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.

  10. Unix version of CALOR89 for calorimeter applications

    International Nuclear Information System (INIS)

    Handler, T.

    1992-01-01

    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

  11. 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.

  12. Simulación CFD de la transferencia de calor en un reactor de hidrotratamiento de aceites vegetales de segunda generación

    OpenAIRE

    Mendoza Sépulveda, César Camilo

    2013-01-01

    Resumen: Se desarrolló un modelo CFD que permite representar la transferencia de calor en un reactor de hidrotratamiento de aceites vegetales. Este modelo permitió evaluar la transferencia de calor para distintas configuraciones del reactor. En el proceso de hidrotratamiento de aceites vegetales se transforma el aceite en un líquido con cero contenido de azufre y excelentes propiedades como combustible diesel. El proceso se basa en la adición de hidrógeno a alta presión en un reactor de lecho...

  13. 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.

  14. Caloric utilization of sorbitol and isomalt in the rat

    International Nuclear Information System (INIS)

    Figdor, S.K.; Allingham, R.P.; Kita, D.A.; Hobbs, D.C.

    1987-01-01

    Sorbitol and isomalt are modified saccharides used to substitute for the physical properties of sucrose in various prepared foods. The merits of the various methods for determining caloric availability were reviewed. Balance and growth curve methods are inaccurate and inappropriate for determination of the caloric availability of these substances when present in diets at low concentrations, whereas the radiolabel disposition method is a direct and precise measure of utilization. Accordingly, the authors administered uniformly 14 C-labeled material to rats and collected excreta and expired air. The appearance of about half of the label in CO 2 indicated that, by comparison with labeled glucose, about 80% of the orally administered sorbitol and isomalt was calorically available to the rat. The high caloric availabilities of these materials were confirmed by the appearance in feces of only 14 and 12% of the administered label from sorbitol and isomalt, respectively

  15. 21 CFR 874.1800 - Air or water caloric stimulator.

    Science.gov (United States)

    2010-04-01

    ... vestibular function testing of a patient's body balance system. The vestibular stimulation of the... stimulator. (a) Identification. An air or water caloric stimulator is a device that delivers a stream of air...

  16. The minimal ice water caloric test compared with established vestibular caloric test procedures.

    Science.gov (United States)

    Schmäl, Frank; Lübben, Björn; Weiberg, Kerstin; Stoll, Wolfgang

    2005-01-01

    Caloric testing of the vestibular labyrinth is usually performed by classical caloric test procedures (CCTP) using water warmed to 30 degrees C and 44 degrees C. Ice water irrigation (4 degrees C) is usually not performed, although it might be useful as a bedside test. To verify the validity of the Minimal Ice Water Caloric Test (MIWCT), comparative video-oculographic investigations were performed in 22 healthy subjects using ice water (0.5 ml, 1.0 ml, 2 ml), CCTP, and cold air (27 degrees C). Frequency, amplitude, slow phase velocity (SPV), the onset, and the duration of nystagmus were documented. After addition of three ice cubes, the temperature of conventional tap water (16 degrees C) fell within 13 min to 4 degrees C. In pessimum position the subjects demonstrated no nystagmus response. Compared to CCTP, MIWCT was associated with a significantly later onset of nystagmus and a significant prolongation of the nystagmus reaction. In contrast to air stimulation (27 degrees C), a significant Spearman's correlation was noted between MIWCT (1 and 2 ml) and established CCTP in respect of essential nystagmus parameters (frequency, amplitude and SPV). Furthermore, MIWCT (0.5 and 1 ml) showed a higher sensitivity and specificity with regard to the detection of canal paresis based on Jongkees' formula compared to stimulation with air 27 degrees C. Thus, MIWCT appears to be a suitable procedure for bedside investigation of vestibular function outside the vestibular laboratory, e.g. in a hospital ward, where bedridden patients with vertigo occasionally require vestibular testing.

  17. Procedimiento para la extracción de gluten contenido en alimentos, procesados y no procesados por calor, compatible con un ensayo de inmunoabsorción ligado a enzimas, composición y kits que comprenden dicha composición

    OpenAIRE

    López Villar, Elena; Llorente Gómez, María de las Mercedes; Méndez Cormán, Enrique

    2001-01-01

    La presente invención se refiera a, en general, el análisis de alimentos para enfermos celiacos, y, especialmente, se refiere a un procedimiento para la extracción de gluten de alimentos, compatible con un ensayo de inmunoabsorción ligado a enzimas (ELISA), a composiciones adecuadas para la puesta en práctica de dicho procedimiento, a kits que comprenden dichas composiciones y a un procedimiento para la cuantificación por ELISA del gluten presente en los alimentos.

  18. 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.

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

    OpenAIRE

    Calzada León Raúl; Altamirano Bustamante Nelly

    2014-01-01

    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,...

  20. 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.

  1. Entrevista con Patricia Ariza

    Directory of Open Access Journals (Sweden)

    Esperanza Londoño La Rotta

    2017-01-01

    Full Text Available Pensamiento, Palabra y Obra entrevista a una artista, feminista y activista política, quien como mujer y artista ha permitido pensar el arte más allá de un simple espectáculo. Toda una vida dedicada al teatro y a darle voz, a través de sus obras, a víctimas del conflicto colombiano, defensora de derechos humanos; además de hacer evidente en su vida y a través de la plataforma “Artistas por la paz”, las múltiples relaciones que se pueden establecer entre el arte, la construcción de paz y la resolución de conflictos. Hablamos en su casa, en medio del calor de la bienvenida con Patricia Ariza, directora del festival alternativo de teatro, de Mujeres en Escena y de la Corporación Colombiana de Teatro, entre otras muchas actividades que voluntariamente su espíritu libertario ha asumido. Esta entrevista se realizó antes del 2 de octubre, pero con la revisión de los acuerdos que propició el plebiscito ganado por una ínfima minoría por el no, sigue siendo vigente este planteamiento.

  2. 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...

  3. 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

  4. Proyecto integral de acondicionamiento de cuerpos momificados de la colección del Museo de La Plata

    Directory of Open Access Journals (Sweden)

    Reca, María Marta

    2009-01-01

    Full Text Available Con motivo de la decisión institucional de no exhibir restos humanos de procedencia americana, desde la Unidad de Conservación y Exhibición del Museo de La Plata se inició la delicada tarea de retirar las piezas de la sala de exhibición y acondicionar un espacio especial para el resguardo de la colección de cuerpos momificados. Dicha colección está conformada por veinte cuerpos en diferente estado de conservación y con características específicas. El presente estudio tiene por objeto dar cuenta de los procedimientos y las distintas etapas a considerar en un trabajo planificado y sistemático. En tal sentido, se explicitan, desde la conservación preventiva, los criterios que orientaron cada una de las etapas. El proyecto, en curso, contempla las instancias de evaluación, registro, tratamiento, definición de los contenedores y características del depósito.

  5. Análisis de falla en evaporadores de placas de aluminio de sistemas de acondicionamiento de aire automotriz

    Directory of Open Access Journals (Sweden)

    Santiago Mendoza Hurtado

    2011-01-01

    Full Text Available Se caracterizaron los tipos de fallas a partir del estudio de tres perfiles de evaporadores de placas de aleación de aluminio, puestos fuera de servicio por fugas del refrigerante y obtenidos en talleres de refrigeración automotriz en la ciudad de Barranquilla. Luego se aplicaron las pruebas de la metodología del análisis de falla. Se comprobó que los mecanismos de falla fueron principalmente corrosión con algunas situaciones tendientes a fractura frágil; además, las condiciones ambientales de la ciudad de Barranquilla son factores influyentes en los mecanismos de corrosión.

  6. 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

    OpenAIRE

    Mario Cúnsulo; Alejandra Kurbán; Alberto Papparelli

    2011-01-01

    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 ...

  7. 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.

  8. Measuring caloric response: comparison of different analysis techniques.

    Science.gov (United States)

    Mallinson, A I; Longridge, N S; Pace-Asciak, P; Ngo, R

    2010-01-01

    Electronystagmography (ENG) testing has been supplanted by newer techniques of measuring eye movement with infrared cameras (VNG). Most techniques of quantifying caloric induced nystagmus measure the slow phase velocity in some manner. Although our analysis is carried out by very experienced assessors, some systems have computer algorithms that have been "taught" to locate and quantify maximum responses. We wondered what differences in measurement might show up when measuring calorics using different techniques and systems, the relevance of this being that if there was a change in slow phase velocity between ENG and VNG testing when measuring caloric response, then normative data would have to be changed. There are also some subjective but important aspects of ENG interpretation which comment on the nature of the response (e.g. responses which might be "sporadic" or "scant"). Our experiment compared caloric responses in 100 patients analyzed four different ways. Each caloric was analyzed by our old ENG system, our new VNG system, an inexperienced assessor and the computer algorithm, and data was compared. All four systems made similar measurements but our inexperienced assessor failed to recognize responses as sporadic or scant, and we feel this is a limitation to be kept in mind in the rural setting, as it is an important aspect of assessment in complex patients. Assessment of complex VNGs should be left to an experienced assessor.

  9. REDES DE INTERCAMBIO DE CALOR APLICADAS A LA ESTERIFICACIÓN DE ACEITES VEGETALES USADOS

    Directory of Open Access Journals (Sweden)

    María F. Laborde

    2014-01-01

    Full Text Available E n este trabajo se presenta la aplicación de redes de intercambio de calor (RIC a la esterificación de aceites vegetales usados (AVUs con catálisis ácida para la producción de biodiesel. Se aplican distintos métodos para obtener las cantidades mínimas de calor y la RIC para una capacidad de procesamiento de 0,19 kg/s de AVUs. Se considera una diferencia de temperatura mínima (∆Tmin de 10°C y los requerimientos mínimos de calentamiento y enfriamiento, resultan ser de 4629,87 W y de 10066,30 W, respectivamente. Al aplicar la red de intercambio calórico disminuye en un 78,92% el servicio de vapor requerido en el proceso y en un 62,48% el servicio de agua de enfriamiento, lo que demuestra que la integración reduce los requerimientos energéticos respecto al proceso no integrado.

  10. DINÁMICA DE UN REACTOR DE BIOPELÍCULA ANAEROBIA TIPO INTERCAMBIADOR DE CALOR (RBAIC

    Directory of Open Access Journals (Sweden)

    Carlos Ramiro Escalera Vásquez

    2005-01-01

    Full Text Available Las características dinámicas de un reactor de biopelícula anaerobio tipo intercambiador de calor (RBAIC, usado para el tratamiento de aguas residuales de melazas, fueron estudiadas experimentalmente. Se realizaron experimentos para estudiar la respuesta del reactor a las sobrecargas orgánicas. También se estudiaron los efectos de los cambios de temperatura de las paredes calientes y las temperaturas ambientales, sobre la eficiencia del reactor, bajo condiciones de estado estacionario. Se demostró que el RBAIC es estable ante la ocurrencia de sobrecarga orgánica. Se concluyó que existe una separación de fases microbianas dentro del reactor, en condiciones normales de operación. Es decir, las bacterias acidogénicas predominan en la masa líquida recirculante y las heteroacetogénicas y metanogénicas lo hacen en la biopelícula adherida a las paredes calientes de transferencia de calor, lo cual implica que los cambios de la temperatura de la pared afectan de mayor manera a la eficiencia de remoción, que los cambios de temperatura del entorno. El RBAIC es una configuración  novedosa, con características energéticas favorables para el tratamiento de aguas residuales de la industria alimenticia.

  11. 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.

  12. Factor de cielo visible y el efecto de isla de calor en Valparaíso

    Directory of Open Access Journals (Sweden)

    Claudio Carrasco

    2016-11-01

    Full Text Available La forma urbana transforma el territorio y su comportamiento climático. La morfología de la ciudad varía desde sus centros hasta su periferia, así como también varía en densidad poblacional, en el uso temporal de las edi caciones, en la presencia o ausencia de vegetación o en la densidad de transporte. Estas variables condicionan el comportamiento térmico del espacio público. A partir de la consideración de la visibilidad del cielo desde el cañón urbano se de ne el SVF (Sky View Factor, que está relacionado con el almacenamiento térmico y la ventilación del espacio de la calle. Ambas variables son fundamentales en el confort peatonal y en el calentamiento de la ciudad. En este trabajo se presentan desempeños climáticos asociados a la morfología de la ciudad de Valparaíso, ubicada en un clima mediterráneo costero. Se realizaron mediciones climáticas simultáneas en diversos lugares de la ciudad que se correlacionaron con parámetros geométricos y materiales de los lugares registrados. Se determina una estrecha relación entre morfología urbana, comportamiento térmico del espacio público y aumento de la temperatura favoreciendo el fenómeno de isla de calor (UHI. Estos valores permitirían predecir en forma más precisa las condiciones climáticas en el nivel de calle y la manera cómo afecta en el fenómeno urbano de isla de calor (UHI.

  13. Metabolic effects of intermittent access to caloric or non-caloric sweetened solutions in mice fed a high-caloric diet.

    Science.gov (United States)

    Soto, Marion; Chaumontet, Catherine; Even, Patrick C; Azzout-Marniche, Dalila; Tomé, Daniel; Fromentin, Gilles

    2017-06-01

    Human consumption of obesogenic diets and soft drinks, sweetened with different molecules, is increasing worldwide, and increases the risk of metabolic diseases. We hypothesized that the chronic consumption of caloric (sucrose, high-fructose corn syrup (HFCS), maltodextrin) and non-caloric (sucralose) solutions under 2-hour intermittent access, alongside the consumption of a high-fat high-sucrose diet, would result in differential obesity-associated metabolic abnormalities in mice. Male C57BL/6 mice had ad libitum access to an HFHS diet and to water (water control group). In addition, some mice had access, 2h/day, 5days/week (randomly chosen) for 12weeks, to different solutions: i) a sucrose solution (2.1kJ/ml), ii) an HFCS solution (2.1kJ/ml), iii) a maltodextrin solution (2.1kJ/ml) and a sucralose solution (60mM) (n=15/group). Despite no changes in total caloric intake, 2h-intermittent access to the sucrose, HFCS or maltodextrin solutions led to increased body weight and accumulation of lipids in the liver when compared to the group consuming water only. The HFCS and sucrose solutions induced a higher fat mass in various fat depots, glucose intolerance, increased glucose oxidation at the expense of lipid oxidation, and a lower hypothalamic expression of NPY in the fasted state. HFCS also reduced proopiomelanocortin expression in the hypothalamus. 2h-intermittent access to sucralose did not result in significant changes in body composition, but caused a stronger expression of CART in the hypothalamus. Finally, sucrose intake showed a trend to increase the expression of various receptors in the nucleus accumbens, linked to dopamine, opioid and endocannabinoid signaling. In conclusion, 2h-intermittent access to caloric solutions (especially those sweetened with sucrose and HFCS), but not sucralose, resulted in adverse metabolic consequences in high-fat high-sucrose-fed mice. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Caloric requirement of the critically ill septic patient

    International Nuclear Information System (INIS)

    Shizgal, H.M.; Martin, M.F.

    1988-01-01

    The caloric requirement of the critically ill septic patient was determined by measuring body composition, by multiple isotope dilution, before and at 2-wk intervals while receiving total parenteral nutrition (TPN) in 86 septic and 57 nonseptic malnourished patients. All patients received a TPN solution containing 25% dextrose and 2.75% crystalline amino acids. The body composition of the nonseptic patients, who received 51.9 +/- 1.5 kcal/kg.day, improved significantly, while that of the septic patients, receiving 46.8 +/- 1.1 kcal/kg.day was only maintained. The relationship between caloric intake and the restoration of a malnourished body cell mass (BCM) was determined for each group by correlating, using multiple linear regression, the mean daily change in the BCM with the caloric intake and the nutritional state, as determined by body composition. According to the resultant regressions, an intake of 35.1 and 50.7 kcal/kg.day was required to maintain the BCM of the septic and nonseptic patients, respectively. To restore a depleted BCM, caloric intakes in excess of this amount are required

  15. Dal calore all'entropia una introduzione alla termodinamica

    CERN Document Server

    Vicentini Missoni, Matilde

    1992-01-01

    Panta rei : processi ed equilibrio ; l'universo termodinamico : l'aspetto processuale ; il punto di vista dei processi come bilancio tra proprietà dell'equilibrio ; il fluire dell'energia ; automobili, frigoriferi e pompe di calore : informazioni tecnologiche ; e allora ? l'entropia ; la termostatica come teoria assiomatica ; la termodinamica dei processi.

  16. The reno-protective effects of dietary caloric restriction against ...

    African Journals Online (AJOL)

    Studies have shown that dietary caloric restriction (CR) without malnutrition can increase longevity. This study aims to evaluate the protective effects of CR on oxidative stress, lipid peroxidation and inflammatory cytokines in the kidney of streptozotocin-induced diabetic rats. Forty 12-week old male Wistar rats, weighing ...

  17. Phenomenological approach to the caloric theory of heat

    Czech Academy of Sciences Publication Activity Database

    Mareš, Jiří J.; Hubík, Pavel; Šesták, Jaroslav; Špička, Václav; Krištofik, Jozef; Stávek, J.

    2008-01-01

    Roč. 474, č. 1-2 (2008), s. 16-24 ISSN 0040-6031 R&D Projects: GA AV ČR IAA1010404; GA AV ČR IAA100100639 Institutional research plan: CEZ:AV0Z10100521 Keywords : caloric * entropy * heat * thermodynamics * heat engines Subject RIV: BJ - Thermodynamics Impact factor: 1.659, year: 2008

  18. Quantifying the association between obesity, automobile travel, and caloric intake.

    Science.gov (United States)

    Behzad, Banafsheh; King, Douglas M; Jacobson, Sheldon H

    2013-02-01

    The objective of this study is to assess the association between average adult body mass index (BMI), automobile travel, and caloric intake in the US in order to predict future trends of adult obesity. Annual BMI data (1984-2010) from the Behavioral Risk Factor Surveillance System (BRFSS), vehicle miles traveled data (1970-2009) from the Federal Highway Administration, licensed drivers data (1970-2009) from the Federal Highway Administration, and adult average daily caloric intake data (1970-2009) from the US Department of Agriculture were collected. A statistical model is proposed to capture multicollinearity across the independent variables. The proposed statistical model provides an estimate of changes in the average adult BMI associated with changes in automobile travel and caloric intake. According to this model, reducing daily automobile travel by one mile per driver would be associated with a 0.21 kg/m(2) reduction in the national average BMI after six years. Reducing daily caloric intake by 100 calories per person would be associated with a 0.16 kg/m(2) reduction in the national average BMI after three years. Making small changes in travel or diet choices may lead to comparable obesity interventions, implying that travel-based interventions may be as effective as dietary interventions. Copyright © 2012 Elsevier Inc. All rights reserved.

  19. Funcionamiento de un termosifón cilíndrico con distintos fluidos de trabajo

    OpenAIRE

    Arcís Tellería, José

    2010-01-01

    Actualmente, las investigaciones llevadas a cabo en el campo de la transmisión de calor mediante termosifón, tratan de conocer el comportamiento de las distintas sustancias, con el fin de optimizar dicha tecnología para la transferencia de calor. En este sentido, en el Área de Máquinas y Motores Térmicos, perteneciente al Departamento de Ingeniería Mecánica, Energética y de Materiales de la Universidad Pública de Navarra, se está llevando a cabo un proyecto de investigación con fluidos de tra...

  20. La vegetación como sistema de control para las Islas de Calor Urbano en Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Maria Goretti Salas Esparza

    2017-06-01

    Full Text Available A nivel mundial, el territorio ha experimentado un proceso de urbanización, el cual ha modificado las condiciones físicas y climatológicas como consecuencia de la densificación y construcción de las zonas urbanas, sobre todo a partir de la utilización de materiales que retienen el calor y que propician el fenómeno de isla de calor urbano (ICU, término establecido por Gordon Manley en 1958 (Fernández, 1996. Este trabajo evalúa el impacto que tienen las áreas verdes para actuar como sistema de control de isla de calor sobre Ciudad Juárez, Chihuahua, durante el verano del 2016. La metodología consistió en analizar cuatro áreas verdes para determinar la diferencia de temperatura que existe entre las zonas arboladas y las no arboladas, registrando temperaturas con sensores Hobo®, cada 15 minutos. Los resultados obtenidos demostraron que existe una diferencia de temperatura de 3,82 °C entre los lugares arbolados y no arbolados en el área verde con mayor nivel de vegetación, mientras que el área verde con menor nivel de vegetación se encontró una diferencia de 0,53 °C. Sin embargo, el impacto que tendrán sobre la zona urbana dependerá de la configuración y características de la misma área verde.   Documeto fianciado bajo el marco Tesis de Maestría en Planificación y Desarrollo Urbano " Áreas verdes como sistema de control para las Islas de Calor Urbano en Ciudad Juárez, Chihuahua".Universidad Autónoma de Ciudad Juárez

  1. Factors contributing to the nuclear caloric curve aspect

    International Nuclear Information System (INIS)

    Raduta, Al.H.; Raduta, Ad.R.

    1999-01-01

    After the first experimental evaluation of the nuclear caloric curve a large amount of theoretical work was concentrated to reproduce the transition-like plateau of the caloric curve from 5 MeV temperature. Both dynamical and statistical models have been employed in order to deduce the excitation energy dependence of the temperature of the equilibrated nuclear systems formed in violent heavy ion collisions. For describing such kind of systems a microcanonical model fully obeying the involved physical constrains seems to be the most appropriate option. However, the currently used statistical multifragmentation models (SMM and MMMC ) are not fully satisfying the microcanonical rules. For these reasons the nuclear caloric curve is studied in the present work from the point of view of a sharp microcanonical model. In this respect a detailed analysis concerning the contribution of the various energetic degrees of freedom (binding, Coulomb repulsive and internal excitation) to the curve aspect is performed. The method adopted here consists in suppressing each of the above-mentioned degrees of freedom once at a time keeping the rest of the system parameters unchanged. The Coulomb repulsive (V) and excitation (ε) degrees of freedom are suppressed by fixing the respective energies to zero. The binding degree of freedom (B) is 'suppressed' by fixing it to the constant value of - 8.5 MeV/nucleon for all fragments. The effect of the correlation between the Coulomb repulsive and the excitation degrees of freedom on the caloric curve aspect is also studied. The resulting caloric curves are denoted T -V , T -ε , T -B , T -Vε . One may observe that the suppression of the excitation degree of freedom has the effect of lifting and diminishing the plateau and the suppression of the Coulomb degree of freedom is lowering the plateau and almost washes-out the plateau-like region. The spectacular effect concerns the complementary moves T -Vε and - B: While the Vε couple suppression

  2. 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)

    1993-12-31

    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.

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

    Directory of Open Access Journals (Sweden)

    Rangel Jara Hermes Augusto

    1997-01-01

    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.

  4. 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.

  5. 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

  6. 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.

  7. An in vivo magnetic resonance spectroscopy study of the effects of caloric and non-caloric sweeteners on liver lipid metabolism in rats

    NARCIS (Netherlands)

    Janssens, S.; Ciapaite, J.; Wolters, J.C.; van Riel, N.A.; Nicolay, K.; Prompers, J.J.

    2017-01-01

    We aimed to elucidate the effects of caloric and non-caloric sweeteners on liver lipid metabolism in rats using in vivo magnetic resonance spectroscopy (MRS) and to determine their roles in the development of liver steatosis. Wistar rats received normal chow and either normal drinking water, or

  8. An In Vivo Magnetic Resonance Spectroscopy Study of the Effects of Caloric and Non-Caloric Sweeteners on Liver Lipid Metabolism in Rats

    NARCIS (Netherlands)

    Janssens, Sharon; Ciapaite, Jolita; Wolters, Justina C.; van Riel, Natal A.; Nicolay, Klaas; Prompers, Jeanine J.

    2017-01-01

    We aimed to elucidate the effects of caloric and non-caloric sweeteners on liver lipid metabolism in rats using in vivo magnetic resonance spectroscopy (MRS) and to determine their roles in the development of liver steatosis. Wistar rats received normal chow and either normal drinking water, or

  9. Determinación del requerimiento de frío y de calor en duraznero [Prunus persica (L. Batsch.] mediante un modelo de correlación

    Directory of Open Access Journals (Sweden)

    CHAAR, J

    2012-11-01

    Full Text Available Los árboles frutales de hoja no persistente poseen un período de reposo entre los ciclos vegetativos. Para salir de reposo invernal, las yemas deben acumular primero frío (endodormancia y luego calor (ecodormancia.El objetivo de este trabajo fue determinar el requerimiento de frío y de calor en cinco cultivares de duraznero mediante un método de correlación, con datos de fecha de plena floración y temperatura del aire de siete años, en el este de Mendoza. El requerimiento de frío varió entre 914 y 1262 unidades de frío, mientras que el de calor fluctuó entre 2177 y 6490 horas grado de crecimiento. Excepto en cv. “Prima”, la variabilidad entre años del requerimiento de frío (coeficiente de variación, CV: 18,3 a 18,9% fue mayor que la correspondiente al requerimiento de calor, (CV: 6,9 a 13,9%. Los requerimientos de calor disminuyeron en años de mayor acumulación de frío e indicaron una compensación. El modelo utilizado, permite disponer de información más precisa sobre los requerimientos térmicos de los cultivares, y así poder realizar una zonificación que racionaliceel cultivo y maximice su aprovechamiento, en las áreas agroclimáticamente adecuadas.

  10. 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.

  11. Estudio estructural en instalaciones de bomba de calor : Structural study of heat pump´s installations

    Directory of Open Access Journals (Sweden)

    Oscar M. Cruz Fonticiella

    2013-06-01

    Full Text Available Se investigan las irreversibilidades de una bomba de calor, con análisis exergéticos y estructurales. Se utilizó una instalación experimental de una bomba de calor lográndose datos y cálculos de la eficiencia de la compresión, temperaturas medias de los focos caliente y frío del ciclo, diferencia de temperatura a la salida del condensador, media logarítmica del evaporador, caídas de presiones del condensador y el evaporador y un análisis exergético y estructural con las propiedades termodinámicas en los puntos clave del ciclo, coeficiente de comportamiento del ciclo, balances de masas, energías y entropía, entropía generada en cada componente, balance de exergía con las irreversibilidades en cada componente, eficiencia exergética, defecto de eficiencia y coeficientes de vínculos estructurales Se exploraron las potencialidades de mejora de cada componente para una posterior optimización termoeconómica.The irreversibility of a heat pump with exergy and structural analysis is investigated. An experimental installation of a heat pump and calculations achieving data compression efficiency, the average temperature of hot and cold spots in the cycle was used, The temperature difference output condenser, log mean evaporator , pressures drops condenser and evaporator and structural exergy analysis and thermodynamic properties at key points of the cycle, the cycle coefficient of performance, mass balances, energy and entropy, entropy generated in each component, the availability balance irreversibilities in each component , exergetic efficiency, default coefficients efficiency and structural links were obtained. The potential for improvement for each component for further thermoeconomic optimization were explored

  12. Estudio estructural en instalaciones de bomba de calor; Structural study of heat pump´s installations

    Directory of Open Access Journals (Sweden)

    Oscar M. Cruz Fonticiella

    2013-06-01

    Full Text Available Se investigan las irreversibilidades de una bomba de calor, con análisis exergéticos y estructurales. Se utilizó una instalación experimental de una bomba de calor lográndose datos y cálculos de la eficiencia de la compresión, temperaturas medias de los focos caliente y frío del ciclo, diferencia de temperatura a la salida del condensador, media logarítmica del evaporador, caídas de presiones del condensador y el evaporador y un análisis exergético y estructural con las propiedades termodinámicas en los puntos clave del ciclo, coeficiente de comportamiento del ciclo, balances de masas, energías y entropía, entropía generada en cada componente, balance de exergía con las irreversibilidades en cada componente, eficiencia exergética, defecto de eficiencia y coeficientes de vínculos estructurales Se exploraron las potencialidades de mejora de cada componente para una posterior optimización termoeconómica.  The irreversibility of a heat pump with exergy and structural analysis is investigated. An experimental installation of a heat pump and calculations achieving data compression efficiency, the average temperature of hot and cold spots in the cycle was used, The temperature difference output condenser, log mean evaporator , pressures drops condenser and evaporator and structural exergy analysis and thermodynamic properties at key points of the cycle, the cycle coefficient of performance, mass balances, energy and entropy, entropy generated in each component, the availability balance irreversibilities in each component , exergetic efficiency, default coefficients efficiency and structural links were obtained. The potential for improvement for each component for further thermoeconomic optimization were explored.

  13. Rabdomiolisis asociada al tratamiento con valaciclovir

    Directory of Open Access Journals (Sweden)

    Héctor Enríquez Gómez

    2012-03-01

    Full Text Available La rabdomiolisis es un efecto secundario asociado a un buen número de fármacos, entre ellos los antivirales. Describimos un caso de rabdomiolisis secundaria a valaciclovir, efecto no descrito anteriormente en laliteratura, en un contexto clínico muy especial. Se trata de un varón queingresa por un golpe de calor secundario a la realización de ejercicio físicoextremo. Durante su ingreso se comienza tratamiento con valaciclovir porun herpes nasolabial, observándose en los días siguientes una marcadaelevación de las cifras de CPK que desaparece con la suspensión del mismo. Proponemos, por tanto, que ante la administración de valaciclovir ensituaciones que puedan comportar daño mitocondrial habría que realizarmonitorización estrecha de los niveles de CPK

  14. 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

  15. Estudio del comportamiento de una sustancia de cambio de fase con condición de borde convectiva

    OpenAIRE

    Lozano, Ricardo; Villa Saravia, Luis Tadeo; Bouciguez, Angélica Carmen

    2016-01-01

    El proceso de fusión - solidificación, ha sido abordado con anterioridad, procurando soluciones a problemas de difusión con cambio de fase, cuando estando inicialmente solidas a la temperatura de fusión son sometidas a un flujo de calor por uno de sus laterales. Un flujo interesante es el convectivo, pues es la forma más realista de entrada o extracción de calor a la sustancia de cambio de fase. Dada esta condición de borde resulta interesante observar el comportamiento de la sustancia, cuand...

  16. 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.

  17. 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.

  18. Caloric effects in ferroic materials: new concepts for cooling

    Energy Technology Data Exchange (ETDEWEB)

    Faehler, Sebastian; Roessler, Ulrich K. [IFW Dresden (Germany); Kastner, Oliver; Eggeler, Gunther [Ruhr Universitaet Bochum (Germany); Eckert, Juergen [IFW Dresden (Germany); TU Dresden, Institut fuer Werkstoffwisssenschaft, Dresden (Germany); Emmerich, Heike [Universitaet Bayreuth (Germany); Entel, Peter [Universitaet Duisburg-Essen, Duisburg (Germany); Mueller, Stefan [Institut fuer Angewandte Mathematik, Bonn (Germany); Quandt, Eckhard [Institute for Materials Science, Christian-Albrechts-Universitaet (CAU), Kiel (Germany); Albe, Karsten [TU Darmstadt (Germany)

    2012-02-15

    Refrigeration is one of the main sinks of the German and European electricity consumption and accordingly contributes to worldwide CO{sub 2} emissions. High reduction potentials are envisaged if caloric effects in solid materials are used. The recent discovery of giant entropy changes associated with ferroelastic phase transformations promises higher efficiency. Ferroic transitions enhance the entropy change of magneto-, elasto-, baro-, and electro-caloric effects. Furthermore, because the refrigerant is in a solid state, this technology completely eliminates the need for halofluorocarbon refrigerants having a high global-warming potential. The smaller footprint for operation and the scalable mechanism open up further applications such as cooling of microsystems. While the principal feasibility of magnetocaloric refrigeration is already evident, it requires large magnetic fields (>2 T) which hampers wide industrial and commercial application. It is expected that this obstacle can be overcome by materials with lower hysteresis and by using stress- or electric fields. In order to accelerate research on ferroic cooling, the Deutsche Forschungsgemeinschaft (DFG) decided to establish the priority program SPP 1599 in April 2011. In this article we will address the major challenges for introducing ferroic materials in practical cooling applications: energy efficiency, effect size, and fatigue behavior. Solid state cooling in this sense can be based on the following ''ferroic-caloric'' classes of materials: ferroelastic shape memory alloys, ferromagnetic shape memory alloys, and ferroelectric materials and their possible combinations in materials with ''multicaloric'' effects. The open questions require the interdisciplinary collaboration of material scientists, engineers, physicists, and mathematicians. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  19. La isla de calor estival en Temuco, Chile

    OpenAIRE

    Alicia Capelli de Steffens; María Cintia Píccolo; Jorge Hernández González; Gustavo Navarrette

    2001-01-01

    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 ...

  20. A crise do socialismo analisada no calor da hora

    Directory of Open Access Journals (Sweden)

    Reginaldo Benedito Dias

    2009-11-01

    Full Text Available O presente artigo demonstra como os acontecimentos que levaram à crise e desintegração dos países do bloco soviético foram analisados no calor dos acontecimentos, tomando como parâmetro os livros "Nós, o povo" e "A desintegração do monolito", selecionados por causa das diferentes perspectivas metodológicas e ideológicas que representam.  

  1. Macronutrients and caloric intake in health and longevity.

    Science.gov (United States)

    Solon-Biet, Samantha M; Mitchell, Sarah J; de Cabo, Rafael; Raubenheimer, David; Le Couteur, David G; Simpson, Stephen J

    2015-07-01

    Both lifespan and healthspan are influenced by nutrition, with nutritional interventions proving to be robust across a wide range of species. However, the relationship between nutrition, health and aging is still not fully understood. Caloric restriction is the most studied dietary intervention known to extend life in many organisms, but recently the balance of macronutrients has been shown to play a critical role. In this review, we discuss the current understanding regarding the impact of calories and macronutrient balance in mammalian health and longevity, and highlight the key nutrient-sensing pathways that mediate the effects of nutrition on health and ageing. © 2015 Society for Endocrinology.

  2. SIMULACION DE LA PUESTA EN MARCHA DE UN REACTOR DE BIOPELÍCULA ANAEROBIA TIPO INTERCAMBIADOR DE CALOR

    Directory of Open Access Journals (Sweden)

    Ramiro Escalera Vásquez

    2009-01-01

    Full Text Available Se ha desarrollado un  modelo de reactor que considera la separación de fases microbianas dentro de un reactor anaerobio tipo intercambiador de calor, donde las bacterias acidogénicas predominan en la masa líquida recirculante y las heteroacetogénicas y metanogénicas lo hacen en la biopelícula adherida a las paredes. El modelo considera también las resistencias difusionales a la transferencia de masa ocasionadas por la capa laminar y la biopelícula. También se consideran las reacciones paralelas y consecutivas propias de la degradación anaerobia de compuestos orgánicos fácilmente biodegradables, por ejemplo, residuos industriales de altas concentraciones de carbohidratos. El modelo de reactor y las ecuaciones pseudo-analíticas para la estimación de los factores de efectividad, desarrolladas para otro tipo de bioreactores anaerobios tales como lechos empacados y fluidizados, pueden utilizarse para estimar la eficacia y evaluar el funcionamiento de un Reactor de Biopelícula Anaerobia tipo Intercambiador de Calor (RBAIC . En este trabajo se ha verificado que los resultados del modelo concuerdan con los resultados experimentales de la eficacia y funcionamiento del RBAIC, dentro del periodo de puesta en marcha.

  3. Modelo matemático para la descripción de la transferencia de calor para tierra vertida

    Directory of Open Access Journals (Sweden)

    Edgardo Jonathan Suárez-Domínguez

    2014-01-01

    Full Text Available La arquitectura de tierra implica procesos constructivos sustentables ya que utiliza materiales vernáculos duraderos cuyos residuos son de bajo impacto al ambiente. La tierra vertida es una técnica a partir de la cual pueden tenerse muros resistentes dentro de la edificación de viviendas pero cuyas propiedades han sido poco evaluadas y representadas a partir de modelos. La transferencia de calor es una de las características más importantes cuando se edifica en zonas calurosas pues implica ciertos niveles de confort para los usuarios. El presente trabajo propone un modelo para determinar la difusividad térmica de tierra vertida con uso potencial para otras determinaciones a diversas temperaturas, algunas implicaciones también son presentadas. Se encontró que el coeficiente de difusividad térmica de muestras de tierra vertida fue de   4.319  10 8 m 2 s 1 , mientras que su calor específico es de 1.1030 kJkg-1K 1 .

  4. Patterns of intraspecific variability in the response to caloric restriction

    Science.gov (United States)

    Gribble, Kristin E.; Kaido, Oksana; Jarvis, George; Mark Welch, David B.

    2014-01-01

    Caloric restriction (CR) is cited as the most robust means of increasing lifespan across a range of taxa, yet there is a high degree of variability in the response to CR, both within and between species. To examine the intraspecific evolutionary conservation of lifespan extension by CR, we tested the effects of chronic caloric restriction (CCR) at multiple food levels and of intermittent fasting (IF) in twelve isolates from the Brachionus plicatilis species complex of monogonont rotifers. While CCR generally increased or did not change lifespan and total fecundity, IF caused increased, unchanged, or decreased lifespan, depending upon the isolate, and decreased total fecundity in all but one isolate. Lifespan under ad libitum (AL) feeding varied among isolates and predicted the lifespan response to CR: longer-lived isolates under AL were less likely to have a significant increase in lifespan under CCR and were more likely to have a significantly shortened lifespan under IF. Lifespan under AL conditions and the response to CR were not correlated with hydroperiodicity of native habitat or with time in culture. Lack of trade-off between lifespan and fecundity under CCR, and differences in lifespan and fecundity under CCR and IF, even when average food intake was similar, suggest that longevity changes are not always directly determined by energy intake and that CCR and IF regimens extend lifespan through diverse genetic mechanisms. PMID:24384399

  5. Aging, neurogenesis, and caloric restriction in different model organisms.

    Science.gov (United States)

    Arslan-Ergul, Ayca; Ozdemir, A Tugrul; Adams, Michelle M

    2013-08-01

    Brain aging is a multifactorial process that is occurring across multiple cognitive domains. A significant complaint that occurs in the elderly is a decrement in learning and memory ability. Both rodents and zebrafish exhibit a similar problem with memory during aging. The neurobiological changes that underlie this cognitive decline are complex and undoubtedly influenced by many factors. Alterations in the birth of new neurons and neuron turnover may contribute to age-related cognitive problems. Caloric restriction is the only non-genetic intervention that reliably increases life span and healthspan across multiple organisms although the molecular mechanisms are not well-understood. Recently the zebrafish has become a popular model organism for understanding the neurobiological consequences but to date very little work has been performed. Similarly, few studies have examined the effects of dietary restriction in zebrafish. Here we review the literature related to memory decline, neurogenesis, and caloric restriction across model organisms and suggest that zebrafish has the potential to be an important animal model for understanding the complex interactions between age, neurobiological changes in the brain, and dietary regimens or their mimetics as interventions.

  6. Comportamiento del gel de sílice como filtro deshumidificador en sistemas de acondicionamiento de aire por compresión de vapor

    Directory of Open Access Journals (Sweden)

    Antonio José Bula Silvera

    2004-01-01

    Full Text Available Con el fin de determinar la tasa de adsorción de humedad por un filtro a base de gel de sílice, se han llevado a cabo una serie de experimentos en los cuales se ha variado la densidad de gel de sílice por unidad de área y la velocidad con que el aire se acerca al filtro. Los resultados mostraron que al disminuir la velocidad del aire y al aumentar la masa de desecante por unidad de área, se consigue mayor nivel de adsorción por parte del filtro. Sin embargo, al adimensionar la cantidad de agua retenida por unidad de masa de desecante, se observa que el filtro con menor densidad presenta mayor efectividad en el proceso de remoción de humedad. Los resultados se presentan en función del tiempo en un lapso de 50 minutos de muestreo.

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

    OpenAIRE

    Pedro Ángel López Miñarro

    2005-01-01

    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, exten...

  8. Morteros acumuladores con parafinas microencapsuladas para el aprovechamiento de la energía solar en suelos radiantes

    OpenAIRE

    Zetola Vargas, Vicente Andrés

    2013-01-01

    Esta Tesis plantea la pregunta de si el uso de morteros con parafinas microencapsuladas combinado con colectores solares térmicos puede reducir el consumo de energías convencionales, en un sistema tradicional de suelo radiante. Se pretende contribuir al conocimiento acerca del efecto que produce en el edificio, el calor latente acumulado en suelos radiantes, utilizando morteros de cemento Portland con material de cambio de fase (PCM), en conjunto con la energía solar. Para cumplir con este pr...

  9. 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.

  10. 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

  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. Estudio teórico-experimental de la amplitud crítica de la capacidad calorífica en la transición líquido-líquido para mezclas líquidas binarias

    OpenAIRE

    Mendez Castro, Pablo

    2014-01-01

    En este trabajo se explica la anomalía crítica de la capacidad calorífica para la transición de fases líquido-líquido en mezclas binarias. Para ello se utiliza un modelo teórico basado en la consideración general de que la función de partición puede ser exactamente identificada con la función de partición del modelo de Ising tridimensional. Bajo esta aproximación se llega al resultado de que la singularidad de la capacidad calorífica está directamente relacionada con la entalpía molar de exce...

  13. Hot or cold? Is monothermal caloric testing useful and cost-effective?

    Science.gov (United States)

    Bush, Matthew L; Bingcang, Christopher M; Chang, Edward T; Fornwalt, Brandon; Rayle, Christopher; Gal, Thomas J; Jones, Raleigh O; Shinn, Jennifer B

    2013-06-01

    Videonystagmography (VNG) is used widely in the assessment of balance dysfunction. The full test battery can be time-consuming and can induce patient discomfort. The purpose of this study was to examine the value of monothermal caloric testing in predicting unilateral caloric weakness, as well as abnormal VNG vestibular and nonvestibular eye movement, while considering the time and reimbursement associated with these tests. In a retrospective review of 645 patients who completed a comprehensive VNG test battery with bithermal caloric testing, we calculated the specificity, sensitivity, and predictive values of monothermal caloric testing in relation to bithermal caloric results and noncaloric VNG results. With unilateral vestibular weakness (UVW) defined as a 25% interear difference, warm-air monothermal caloric testing yielded a sensitivity of 87% and a negative predictive value of 90% for predicting UVW. With a 10% UVW definition, the warm-air caloric testing sensitivity increased to 95% and the negative predictive value to 92%. Warm-air monothermal caloric testing had a positive predictive value of 85% and a negative predictive value of 18% for predicting noncaloric VNG findings; cold-air monothermal and bithermal testing displayed similar results. Isolated monothermal testing is a sensitive screening tool for detecting UVW, but is not adequate for predicting noncaloric VNG results.

  14. 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

  15. 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

  16. 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.

  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. 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.

  19. Caloric Restriction Promotes Structural and Metabolic Changes in the Skin

    Directory of Open Access Journals (Sweden)

    Maria Fernanda Forni

    2017-09-01

    Full Text Available Caloric restriction (CR is the most effective intervention known to enhance lifespan, but its effect on the skin is poorly understood. Here, we show that CR mice display fur coat remodeling associated with an expansion of the hair follicle stem cell (HFSC pool. We also find that the dermal adipocyte depot (dWAT is underdeveloped in CR animals. The dermal/vennule annulus vasculature is enlarged, and a vascular endothelial growth factor (VEGF switch and metabolic reprogramming in both the dermis and the epidermis are observed. When the fur coat is removed, CR mice display increased energy expenditure associated with lean weight loss and locomotion impairment. Our findings indicate that CR promotes extensive skin and fur remodeling. These changes are necessary for thermal homeostasis and metabolic fitness under conditions of limited energy intake, suggesting a potential adaptive mechanism.

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

    DEFF Research Database (Denmark)

    Stankowska, Arwen Urrsula Malgorzata; Gjedde, Albert

    2013-01-01

    People attempt to change their lifestyle when obesity impairs their quality of life. The attempts often fail when multiple habits must be changed in unison. Here we explore relations among food addiction, the neurobiology of habits, and caloric restriction, when people seek to return to normal......, 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...... of uncontrolled eating increases dopamine release in the nucleus accumbens. This and other evidence suggests that abuse of food is a habit learned by means of mechanisms centred in the basal ganglia, with an increased risk of relapse in the presence of associative amplifiers. This risk is predicted...

  1. Caloric Restriction in Lean and Obese Strains of Laboratory ...

    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 improved longevity with caloric restriction (CR) in rodents. Little is known regarding effects of CR in genetically lean versus obese strains. Long-Evans (LE) and Brown Norway (BN) rats make an ideal comparison for a CR study because the percentage body fat of young adult LE rats is double that of BN rats. Male LE and BN rats were either fed ad libitum (AL) or were caloricallyrestricted to 80 or 90% of their AL weight. The percentages of fat, lean and fluid mass were measured non-invasively at 2- to 4-week intervals. Metabolic rate and respiratory quotient were measured after 3, 6, 9 and 12 months of CR. Overall health was scored monthly. The percentage of fat of the LE strain decreased with CR, whereas the percentage of fat of the BN strain remained above the AL group for several months. The percentage of lean mass increased above the AL for both strains subjected to CR. The percentage offluid was unaffected by CR. The average metabolic rate over 22 h of the BN rats subjected to CR was reduced, whereas that of LE rats was increased slightly above the AL group. The respiratory quotient of BN rats wasdecreased with CR. Overall health of the CR LE group was significantly improved compared with t

  2. 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.

  3. Calor específico a bajas temperaturas de alcoholes sólidos vítreos y cristalinos

    Directory of Open Access Journals (Sweden)

    Talón, C.

    2004-02-01

    Full Text Available We present and discuss in this work specific-heat experiments at low temperature that we have conducted on different molecular (hydrogenbonded glasses and crystals. Specifically, we have measured the low-temperature specific heat Cp(T for a set of solid alcohols: normal and fully-deuterated ethanol, 1−and 2−propanol, and glycerol. Ethanol exhibits a very interesting polymorphism presenting three different solid phases at low temperature: a fully-ordered (monoclinic crystal, an orientationally-disordered (cubic crystal or “orientational glass”, and the canonical (amorphous structural glass. By measuring and comparing the low-temperature specific heat of the three phases, in the boson peak range, 2−10 K, as well as in the tunneling-states range, below 1K, we are able to provide a quantitative confirmation that “glassy behavior” is not an exclusive property of amorphous solids. On the other hand, propanol is the simplest monoalcohol with two different stereoisomers (1−and 2−propanol, which allows us to study directly the influence of the spatial rearrangement of atoms on the universal properties of glasses. We have measured the specific heat of both isomers, finding a noteworthy quantitative difference between them. Finally, low-temperature specific-heat data of glassy and crystalline glycerol have also been obtained.

    En este trabajo, presentamos y discutimos experimentos de calorimetría a bajas temperaturas que hemos realizado en diferentes vidrios y cristales moleculares (de puentes de hidrógeno. En concreto, hemos medido el calor específico a bajas temperaturas Cp(T para un conjunto de alcoholes sólidos: etanol normal y completamente deuterado, 1−y 2−propanol, y glicerol. El etanol presenta un muy interesante polimorfismo, con tres fases sólidas diferentes a bajas temperaturas: un cristal estable perfectamente ordenado (monoclínico, un cristal (cúbico con desorden orientacional o “vidrio orientacional”, y

  4. 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)

  5. 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)

  6. 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.

  7. Eating habits and caloric intake of physically active young boys, ages 10 to 14 years.

    Science.gov (United States)

    Thomson, M J; Cunningham, D A; Wearring, G A

    1980-03-01

    Eating habits of 104 male participants (ages 10 to 14 years) in organized ice hockey were compared across age groups and levels of competition. The boys were members of either a highly skilled and intensively active competitive league group (CL) or a less skilled, moderately active house league group (HL). Eating habits were recorded during a school day from a 24 hour recall questionnaire administered by a trained interviewer. The types and amounts of foods eaten were recorded and caloric intake was calculated. The total caloric intakes were not significantly different by age or competitive group. The boys had higher caloric intakes by age (200 kcal day-1) than reported by other studies but the caloric intake by kilogram of body weight was similar. There was a trend towards larger caloric intake by the CL boys (ages 10 and 11 years), however when divided by body weight the differences were not significant suggesting that this trend was due to a greater body weight of the CL boys and not a significantly increased caloric expenditure. The types of foods eaten (fruit, vegetables, dairy, meat, bread or "empty calories") were similar for the two activity groups and across ages 10 to 14 years. The caloric intakes of dairy and meat products of both groups were significantly higher than for the other food groups.

  8. Diseño, Construcción y Calibración de un calorímetro de solución de precisión media

    Directory of Open Access Journals (Sweden)

    Alfredo Gómez O.

    2009-07-01

    Full Text Available Se descriten los criterios de diseño, la construcción y la calibración de un calorímetro isoperit> ólico de solución de precisión media y de bajo costo. Se miden los cambios térmicos mediante un termistor de 15.000 otimios a 293 K, cuya calibración permite encontrar la expresión AT = -52,495 log,o (Rf/Ri para el cambio de temperatura en función de la resistencia, en el rango de trabajo, 297 a 299 K, La sensibilidad termométríca es 0,00158 K/otimio. El error relativo máximo en las medidas calorimétricas con el sistema de calibración benceno-cíclotiexano es de 3%. el de la capacidad calorífica es de 2,74% y el correspondiente a la diferencia de temperatura es de 1,66%, Se encuentran problemas por la gran pendiente de pérdidas de calor, 0,048 K/mln. (valor máximo observado. El coeficiente de transferencia de calor de las paredes del vaso calorimétrico resultó elevado aunque cumple las especificaciones exigidas.

  9. 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

  10. 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.

  11. Acondicionamiento de la arquería de los Nuevos Ministerios en el Paseo de la Castellana. Madrid/España

    Directory of Open Access Journals (Sweden)

    Canosa, Ramón

    1984-10-01

    Full Text Available For the purpose to recover and to revalue this architectural element which limits the inner court of the Nuevos Ministerios with the Paseo de la Castellana, that had remained practically abandoned because of his particular position, it was conceived to use it as an exhibition gallery. To adapt it for this purpose, a simple solution has been planned, based in the maintenance of the existing architecture, with the possibility to put the building back to its original state. So, false ceilings, glass shutter joinery, hidden equipments has been used, the whole absolutely dismountable and without damage for the original construction.Con el fin de recuperar y revalorizar este elemento arquitectónico que limita el gran patio interior de los Nuevos Ministerios en su fachada al Paseo de la Castellana, y que por su especial situación había quedado prácticamente abandonado, se pensó en utilizarlo como galería de exposiciones. Para su adaptación a este propósito, se proyectó una solución muy simple basada en el mantenimiento de la arquitectura existente y en la posibilidad de devolver el edificio a su estado primitivo. Con este fin, se han utilizado falsos techos, cerramientos acristalados de carpintería disimulada, e instalaciones ocultas, que son desmontables en su totalidad, y que, en ningún caso, han afectado a la construcción anterior.

  12. 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.

  13. 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.

  14. Relationship of dieting and restrained eating to self-reported caloric intake in female college freshmen.

    Science.gov (United States)

    Goldstein, Stephanie P; Katterman, Shawn N; Lowe, Michael R

    2013-04-01

    Evidence indicates that restrained eaters do not eat less than unrestrained eaters in the natural environment. However, no study has examined caloric intake in those who are currently dieting to lose, or avoid gaining, weight. The current study examined caloric intake using 24-hour food recalls among individuals dieting to lose weight, dieting to avoid weight gain, restrained nondieters, and unrestrained nondieters. Participants were 246 female college students participating in a weight gain prevention trial. The predicted significant difference in caloric intake across the four groups was found for beverage but not for food intake. Results reinforce past literature indicating that dieting/restraint status does not reflect hypo-caloric intake in naturalistic settings. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Is contextual-potentiated eating dependent on caloric density of food?

    Directory of Open Access Journals (Sweden)

    Fernando Fernández-Aranda

    2009-01-01

    Full Text Available One experiment tested whether a specific context could elicit eating in rats as a result of Pavlovian conditioning and whether this effect depended on the caloric density of food. Thirty two deprived rats experienced two contexts. They had access to food in context A, but no food was available in context B. During conditioning, half of the animals received high density caloric food (HD groups whereas the other half, low density caloric food (LD groups. Then, half of the rats in each type of food group was tested in context A and the other half in context B. The results demonstrated an effect of context conditioning only in HD groups. These findings suggest the relevance of both contextual conditioning and caloric density of food in eating behaviour. Implications for the aetiology of binge eating will be discussed.

  16. Sistema para producir harina nixtamalizada con transporte de bajo cizallamiento

    OpenAIRE

    Ortega-Moody, Jorge; Morales-Sánchez, Eduardo; Hernández-Román, Miguel Ángel; Ruíz-Torres, Maximiano

    2011-01-01

    La tortilla es el alimento más consumido en México y se produce a partir de masa obtenida por el proceso tradicional de nixtamalización. Este método tiene dos inconvenientes: el primero es la cantidad de agua contaminada que genera (nejayote); el segundo, son los tiempos perdidos, ya que la producción es por lotes. Como consecuencia, se han desarrollado métodos continuos que se basan principalmente en la extrusión. Mediante la extrusión con calor, el producto se convierte en un fluido pseudop...

  17. 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.

  18. 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)

    1998-12-31

    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.

  19. Transferencia de calor y su efecto en el proceso de prensado de tableros contrachapados

    Directory of Open Access Journals (Sweden)

    D. Zavala Zavala

    2004-01-01

    Full Text Available El proceso de prensado determina la calidad de los contrachapados (triplay a través de la interrelación de las propiedades tecnológicas de la madera, de las características de los adhesivos y de la interacción de la temperatura y presión que se generan en la prensa. Este trabajo se realizó con la finalidad de analizar el efecto de la transferencia de calor en la polimerización de adhesivos preparados con urea y fenol formaldehído, para determinar la secuela optima de prensado de triplay de 6, 9, 12, 15, 18 y 34 mm de espesor; y para evaluar la compactación de los tableros por efecto de la temperatura y presión durante el prensado. Se utilizó chapa de Pinus herrerai Martínez, P. michoacana Martínez y P. pseudostrobus Lindl., a un contenido de humedad de 6 a 8 %, una prensa calentada con vapor, adhesivo de urea formaldehído para tableros para interiores de 6, 9, 12, 15 y 18 mm y fenol formaldehído para triplay para exteriores de 34 mm de espesor. Se utilizaron ciclos de prensado aplicando temperaturas de 115, 130 y 140 °C y presiones de 10.62 kg·cm-2 (151 psi y 8.51 kg·cm-2 (121 psi en triplay para interiores, y para los tableros tipo exterior de 140, 150 y 160 °C de temperatura y 12.23, 13.29 y 14.34 kg·cm-2 (174, 189 y 204 psi de presión. La temperatura de las líneas de pegamento más externas aumenta rápidamente al cerrarse la prensa y manifiesta una diferencia en relación a las más internas, que tiende a reducirse conforme transcurre el tiempo de prensado, igualándose aproximadamente al 73 % del tiempo para cada tipo de tablero. A través de la evaluación de adhesión de los pegamentos de los tableros para interiores con la norma PS1-95, se determinó que todos pasan las especificaciones requeridas para ese uso En los tableros de 34 mm de espesor, con un incremento de la temperatura de 140 a 160 °C, una presión de 12.23 a 14.34 kg·cm-2 (174 a 204 psi y un contenido de sólidos del fenol formaldehído de 29.9 a 32

  20. Caloric restriction decreases orthostatic tolerance independently from 6° head-down bedrest.

    Directory of Open Access Journals (Sweden)

    John P Florian

    Full Text Available Astronauts consume fewer calories during spaceflight and return to earth with an increased risk of orthostatic intolerance. Whether a caloric deficiency modifies orthostatic responses is not understood. Thus, we determined the effects of a hypocaloric diet (25% caloric restriction during 6° head down bedrest (an analog of spaceflight on autonomic neural control during lower body negative pressure (LBNP. Nine healthy young men completed a randomized crossover bedrest study, consisting of four (2 weeks each interventions (normocaloric bedrest, normocaloric ambulatory, hypocaloric bedrest, hypocaloric ambulatory, each separated by 5 months. Muscle sympathetic nerve activity (MSNA was recorded at baseline following normocaloric and hypocaloric interventions. Heart rate (HR and arterial pressure were recorded before, during, and after 3 consecutive stages (7 min each of LBNP (-15, -30, -45 mmHg. Caloric and posture effects during LBNP were compared using two-way ANOVA with repeated measures. There was a strong trend toward reduced basal MSNA following caloric restriction alone (normcaloric vs. hypocaloric: 22±3 vs. 14±4 burst/min, p = 0.06. Compared to the normocaloric ambulatory, both bedrest and caloric restriction were associated with lower systolic blood pressure during LBNP (p<0.01; however, HR responses were directionally opposite (i.e., increase with bedrest, decrease with caloric restriction. Survival analysis revealed a significant reduction in orthostatic tolerance following caloric restriction (normocaloric finishers: 12/16; hypocaloric finishers: 6/16; χ2, p = 0.03. Caloric restriction modifies autonomic responses to LBNP, which may decrease orthostatic tolerance after spaceflight.

  1. The comparative effect of fasting with and without caloric restriction in Rat on oxidative stress parameters

    OpenAIRE

    Nurina Tyagita; Taufiqurrachman Nasihun; Titiek Sumarawati

    2016-01-01

    Introduction: Fasting, like Islamic Ramadan Fasting, has been associated with health benefits. Islamic Ramadan fasting, a form of caloric restriction (CR) or alternate day fasting that. Studies suggest a comparable effect of ADF and caloric restriction. Despite the fact that fasting can be considered as a form of dietary restriction, fasters tend to have difficulty to reduce their food intake during non-fasting period by overeating leading to the excessive calorie intake. To compare the effec...

  2. 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, 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. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. 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.

  4. 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

  5. Diseño, implantación y evaluación de un plan municipal de prevención y alerta de los efectos del calor sobre la salud de los ciudadanos

    OpenAIRE

    Meléndez Agudín, Mª Victoria

    2017-01-01

    Introducción Según la Organización Mundial de la Salud (OMS) el cambio climático es una importante amenaza emergente para la salud pública en el mundo. El efecto del calor sobre la salud de la población requiere del estudio epidemiológico y el diseño de planes de prevención que vertebren una coordinación total entre los ámbitos internacional, nacional, autonómico y local. La ola de calor que asoló Europa en el año 2003 se asoció con un notable incremento de la morbimortal...

  6. ANÁLISIS DE SENSIBILIDAD POR SIMULACIÓN DEL PROCESO DE DESHIDRATACIÓN DE UNA PLANTA DE ACONDICIONAMIENTO DE GAS NATURAL

    Directory of Open Access Journals (Sweden)

    Eleonora Erdmann

    2012-01-01

    Full Text Available Este trabajo describe el desarrollo de un simulador estacionario para los sectores de deshidratación y estabilización de una planta de tratamiento de gas natural. El simulador fue implementado empleando el simulador comercial ASPEN HYSYS®. El gas considerado en la simulación es un gas típico proveniente de yacimientos de la provincia de Salta (Argentina. La configuración de la planta y las condiciones de operación adoptadas para la simulación son las generalmente empleadas en el tratamiento de gas natural en Salta. Con el simulador desarrollado, se llevó a cabo un estudio de sensibilidad paramétrica de las principales variables operativas del proceso. La simulación realizada permite visualizar el proceso de deshidratación, y realizar un análisis de su comportamiento en función de las variables operativas críticas: concentración de la solución de TEG (70% p – 99% p y temperatura del rehervidor (200 – 375 oF.

  7. Caloric Sweetener Consumption and Dyslipidemia Among US Adults

    Science.gov (United States)

    Welsh, Jean A.; Sharma, Andrea; Abramson, Jerome L.; Vaccarino, Viola; Gillespie, Cathleen; Vos, Miriam B.

    2011-01-01

    Context Dietary carbohydrates have been associated with dyslipidemia, a lipid profile known to increase cardiovascular disease risk. Added sugars (caloric sweeteners used as ingredients in processed or prepared foods) are an increasing and potentially modifiable component in the US diet. No known studies have examined the association between the consumption of added sugars and lipid measures. Objective To assess the association between consumption of added sugars and blood lipid levels in US adults. Design, Setting, and Participants Cross-sectional study among US adults (n=6113) from the National Health and Nutrition Examination Survey (NHANES) 1999–2006. Respondents were grouped by intake of added sugars using limits specified in dietary recommendations (estimate adjusted mean lipid levels. Logistic regression was used to determine adjusted odds ratios of dyslipidemia. Interactions between added sugars and sex were evaluated. Main Outcome Measures Adjusted mean high-density lipoprotein cholesterol (HDL-C), geometric mean triglycerides, and mean low-density lipoprotein cholesterol (LDL-C) levels and adjusted odds ratios of dyslipidemia, including low HDL-C levels (3.8). Results were weighted to be representative of the US population. Results A mean of 15.8% of consumed calories was from added sugars. Among participants consuming less than 5%, 5% to less than 17.5%, 17.5% to less than 25%, and 25% or greater of total energy as added sugars, adjusted mean HDL-C levels were, respectively, 58.7, 57.5, 53.7, 51.0, and 47.7 mg/dL (Padded sugars) the odds of low HDL-C levels were 50% to more than 300% greater compared with the reference group (added sugars). Conclusion In this study, there was a statistically significant correlation between dietary added sugars and blood lipid levels among US adults. PMID:20407058

  8. 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.

  9. 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.

  10. 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

  11. Alternativas de atención odontológica en niños y adolescentes con discapacidad intelectual

    Directory of Open Access Journals (Sweden)

    María Sofía-Lozada-Leidenz

    2012-02-01

    Full Text Available La discapacidad intelectual, representa alrededor 3 al 5% de la población mundial, calculándose aproximadamente 400.000 casos en Venezuela. Gran parte de la cual no recibe atención odontológica, a pesar de tener una mayor predisposición a desarrollar caries y enfermedad periodontal. Objetivo: Compartir las herramientas y alternativas para que el odontopediatra pueda abordar de forma individualizada al paciente y tomar en cuenta el grado de discapacidad intelectual. Materiales y métodos: Fuentes de carácter documental de seis países de los cuales 3 son latinoamericanos: España, Estados Unidos, Egipto, Argentina, Colombia y Venezuela entre los años 1992 y 2012. Resultados: Las alternativas de atención odontológica en niños y adolescentes con discapacidad intelectual según lo observado y analizado en la literatura de España, Egipto, Estados Unidos y países latinoamericanos, se basan en técnicas para el acondicionamiento a la consulta odontológica, restricción física, premedicación oral, sedación y anestesia general. Conclusiones: La atención odontológica de niños y adolescentes con discapacidad intelectual se observa con profundas deficiencias ya que son muy pocos los especialistas capacitados y con vocación para atender a este tipo de pacientes, por lo cual se hace necesario la motivación para establecer las alternativas de atención odontológica que servirán de ayuda para los profesionales que deseen profundizar o iniciarse en la adecuada y correcta atención de este tipo de pacientes.

  12. Effects of Moderate Aerobic Exercise Combined With Caloric Restriction on Circulating Estrogens and IGF-I in Premenopausal Women

    National Research Council Canada - National Science Library

    Williams, Nancy I

    2004-01-01

    This proposal entitled "Effects of moderate aerobic exercise combined with caloric restriction on circulating estrogens and IGF-1 in premenopausal women" will provide important contributions regarding...

  13. Effects of Moderate Aerobic Exercise Combined with Caloric Restriction on Circulating Estrogens and IGF-I in Premenopausal Women

    National Research Council Canada - National Science Library

    Williams, Nancy

    2003-01-01

    The proposal entitled "Effects of moderate aerobic exercise combined with caloric restriction on circulating estrogens and IGF-I in premenopausal women will provide important scientific contributions...

  14. Caloric compensation for lunches varying in fat and carbohydrate content by humans in a residential laboratory.

    Science.gov (United States)

    Foltin, R W; Fischman, M W; Moran, T H; Rolls, B J; Kelly, T H

    1990-12-01

    Two groups of three subjects participated in a residential study that assessed the effects of varying the macronutrient and caloric content of a required lunch meal on subsequent food choice and intake. Lunches contained 431 or 844 kcal, with the caloric differential created by manipulating the calories derived from either fat or carbohydrate (CHO). Each lunch condition (high-fat, high-CHO, low-fat, and low-CHO) was examined for 3 consecutive days. Subjects controlled their own patterns of food intake and could consume any item or number of items at any time during the day or night. There were no significant differences in total daily caloric intake across conditions, indicating that subjects compensated for the caloric content of the lunch regardless of the macronutrient content. Total daily caloric intake under the high-fat and high-CHO conditions was 2824 +/- 151 (mean +/- SEM) and 2988 +/- 187 kcal, respectively, whereas intake under the low-fat and low-CHO conditions was 2700 +/- 131 and 2890 +/- 247 kcal, respectively.

  15. Effect of modest caloric restriction on oxidative stress in women, a randomized trial.

    Science.gov (United States)

    Buchowski, Maciej S; Hongu, Nobuko; Acra, Sari; Wang, Li; Warolin, Joshua; Roberts, L Jackson

    2012-01-01

    It is not established to what extent caloric intake must be reduced to lower oxidative stress in humans. The aim of this study was to determine the effect of short-term, moderate caloric restriction on markers of oxidative stress and inflammation in overweight and obese premenopausal women. Randomized trial comparison of 25% caloric restriction (CR) or control diet in 40 overweight or obese women (body mass index 32±5.8 kg/m(2)) observed for 28 days and followed for the next 90 days. Weight, anthropometry, validated markers of oxidative stress (F(2)-isoprostane) and inflammation (C-reactive protein), adipokines, hormones, lipids, interleukins, and blood pressure were assessed at baseline, during the intervention, and at follow-up. Baseline median F(2)-isoprostane concentration (57.0, IQR = 40.5-79.5) in the CR group was 1.75-fold above average range for normal weight women (32.5 pg/ml). After starting of the caloric restriction diet, F(2)-isoprostane levels fell rapidly in the CR group, reaching statistical difference from the control group by day 5 (median 33.5, IQR = 26.0-48.0, Prestriction diet. Three months after resuming a habitual diet, concentrations of F(2)-isoprostane returned to baseline elevated levels in ∼80% of the women. Oxidative stress can be rapidly reduced and sustained through a modest reduction in caloric intake suggesting potential health benefits in overweight and obese women. Clinicaltrials.gov NCT00808275.

  16. Beneficial impact of aerobic exercises on bone mineral density in obese premenopausal women under caloric restriction.

    Science.gov (United States)

    Hosny, Iman Abbas; Elghawabi, Hamed Samir; Younan, Wael Bahat Fahmy; Sabbour, Adly Aly; Gobrial, Mona Abdel Messih

    2012-04-01

    The aim of this study was to assess the impact of caloric restriction diet versus caloric restriction diet combined with aerobic exercises on bone mineral density (BMD) in obese premenopausal women. Forty premenopausal obese women were classified randomly into two groups equal in number. The first group (group A) received caloric restriction diet, while the second (group B) received caloric restriction diet combined with a program of aerobic exercises, over 3 months. The variables measured in this study included age, weight, height, body mass index, fat weight, lean mass, fat percent, basal metabolic rate, and BMD. The comparison between group A and group B showed significantly higher post-treatment lean mass, basal metabolic rate, and BMD in weight-bearing bones (L2-L4 lumbar spine and total hip) in group B compared to group A. In contrast to the BMD of the weight-bearing bones, the BMD of the radius showed significant decrease between the pre- and post-treatment results in groups A and B with no significant differences between the two groups. A greater improvement in the BMD of weight-bearing bones was observed in obese premenopausal women undergoing caloric restriction combined with exercise than in those not undergoing exercise. Anaerobic exercises incorporated into weight loss programs help offset the adverse effects of dietary restriction on bone.

  17. Estimation of beverage consumption and associated caloric intake in adult Czech population. An observational study.

    Science.gov (United States)

    Adámková, Věra; Hubáček, Jaroslav A; Zimmelová, Petra; Velemínský, Miloš

    2011-01-01

    Food intake is a commonly monitored issue in many studies. In contrast, almost no information has been published on beverage intake in adults. To evaluate beverage intake, we studied a population of 1, 200 adults (656 males and 544 females, aged 18-54 years). The volumes and types of beverages were obtained from self-reported questionnaires. The mean beverage intake was highly variable, with a minimum of 450 mL/day and a maximum of 5,330 mL/day. A mean of 1,575 mL/day was found in the entire population (2,300 mL in males and 840 mL in females). Different patterns in the consumption of beverage types were observed between the males and females. For both males and females, the most common beverage consumed was water followed by tea. The next preferable beverages were alcoholic beer, coffee, and non-alcoholic beer in males and coffee, milk, and alcoholic beer in females. The estimated caloric intake from beverages covers, in most individuals, 10-30% of the recommended daily caloric intake. There is substantial variation among individuals, both in beverage intake and in caloric intake through beverages. The caloric intake from beverages reaches, in some individuals, one-third of the recommended daily caloric rate. © 2011 Neuroendocrinology Letters

  18. Impacto ecológico de los Intercambiadores de calor de tubo y coraza; Ecological impact of Shell and tube heat exchangers

    Directory of Open Access Journals (Sweden)

    Maida Bárbara Reyes Rodríguez

    2015-04-01

    Full Text Available Los intercambiadores de calor de tubo y coraza son de los equipos más importantes en la industria. Su diseño termodinámico se basa en el coeficiente global de transferencia de calor y la caída de presión total. En 2007 se estableció una nueva propiedad termodinámica denominada “Entransía”, que expresa la capacidad de un cuerpo de transferir calor. A la pérdida de esa capacidad se le denomina “Disipación de Entransía”. Para evaluar el impacto ecológico de las máquinas térmicas, Angulo-Brown creó en 1991 la llamada función ecológica. En el presente trabajo se combinó la disipación de entransía con la función ecológica y se creó una nueva expresión para evaluar el impacto ambiental de los intercambiadores de calor. Se realizó además la optimización muti-objetivo de estos equipos. Fueron utilizadas como funciones objetivo la función ecológica y el costo. Para realizar la optimización se utilizó el método de los Algoritmos Genéticos.Shell and tube heat exchangers are ones the most important equipment in the industry. Their thermodynamic design is based on the global heat transference coefficient and the pressure drop. In 2007 was settled a new thermodynamic property denominated “Entransy”, which expresses the capacity of a body to transfer heat. The loss of this capacity is denominated “Entransy Dissipation”. For evaluating the ecological impact of thermal machines, Angulo-Brown created in 1991 the “ecological function”. In this paper the“entransy dissipation” and the ecological function were combined and a new expression for evaluating the ecological impact of shell and tube heat exchangers was created. A multi-objective optimization of this equipment wasalso realized. The ecological function and the cost wereused as objective functions. For carry out the optimization the method of the Genetic Algorithms was used.

  19. 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.

  20. The physics of compensating calorimetry and the new CALOR89 code system

    International Nuclear Information System (INIS)

    Gabriel, T.A.; Brau, J.E.; Bishop, B.L.

    1989-03-01

    Much of the understanding of the physics of calorimetry has come from the use of excellent radiation transport codes. A new understanding of compensating calorimetry was introduced four years ago following detailed studies with a new CALOR system. Now, the CALOR system has again been revised to reflect a better comprehension of high energy nuclear collisions by incorporating a modified high energy fragmentation model from FLUKA87. This revision will allow for the accurate analysis of calorimeters at energies of 100's of GeV. Presented in this paper is a discussion of compensating calorimetry, the new CALOR system, the revisions to HETC, and recently generated calorimeter related data on modes of energy deposition and secondary neutron production (E < 50 MeV) in infinite iron and uranium blocks. 38 refs., 5 figs., 5 tabs

  1. Mechanism-Based Modeling of Gastric Emptying Rate and Gallbladder Emptying in Response to Caloric Intake

    DEFF Research Database (Denmark)

    Guiastrennec, B; Sonne, David Peick; Hansen, M

    2016-01-01

    Bile acids released postprandially modify the rate and extent of absorption of lipophilic compounds. The present study aimed to predict gastric emptying (GE) rate and gallbladder emptying (GBE) patterns in response to caloric intake. A mechanism-based model for GE, cholecystokinin plasma concentr......Bile acids released postprandially modify the rate and extent of absorption of lipophilic compounds. The present study aimed to predict gastric emptying (GE) rate and gallbladder emptying (GBE) patterns in response to caloric intake. A mechanism-based model for GE, cholecystokinin plasma...... concentrations, and GBE was developed on data from 33 patients with type 2 diabetes and 33 matched nondiabetic individuals who were administered various test drinks. A feedback action of the caloric content entering the proximal small intestine was identified for the rate of GE. The cholecystokinin...

  2. Dietary restriction with and without caloric restriction for healthy aging [version 1; referees: 3 approved

    Directory of Open Access Journals (Sweden)

    Changhan Lee

    2016-01-01

    Full Text Available Caloric restriction is the most effective and reproducible dietary intervention known to regulate aging and increase the healthy lifespan in various model organisms, ranging from the unicellular yeast to worms, flies, rodents, and primates. However, caloric restriction, which in most cases entails a 20–40% reduction of food consumption relative to normal intake, is a severe intervention that results in both beneficial and detrimental effects. Specific types of chronic, intermittent, or periodic dietary restrictions without chronic caloric restriction have instead the potential to provide a significant healthspan increase while minimizing adverse effects. Improved periodic or targeted dietary restriction regimens that uncouple the challenge of food deprivation from the beneficial effects will allow a safe intervention feasible for a major portion of the population. Here we focus on healthspan interventions that are not chronic or do not require calorie restriction.

  3. SirT1 regulates energy metabolism and response to caloric restriction in mice.

    Directory of Open Access Journals (Sweden)

    Gino Boily

    Full Text Available The yeast sir2 gene and its orthologues in Drosophila and C. elegans have well-established roles in lifespan determination and response to caloric restriction. We have studied mice carrying two null alleles for SirT1, the mammalian orthologue of sir2, and found that these animals inefficiently utilize ingested food. These mice are hypermetabolic, contain inefficient liver mitochondria, and have elevated rates of lipid oxidation. When challenged with a 40% reduction in caloric intake, normal mice maintained their metabolic rate and increased their physical activity while the metabolic rate of SirT1-null mice dropped and their activity did not increase. Moreover, CR did not extend lifespan of SirT1-null mice. Thus, SirT1 is an important regulator of energy metabolism and, like its orthologues from simpler eukaryotes, the SirT1 protein appears to be required for a normal response to caloric restriction.

  4. 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,

  5. 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

  6. High-throughput search for caloric materials: the CaloriCool approach

    Science.gov (United States)

    Zarkevich, N. A.; Johnson, D. D.; Pecharsky, V. K.

    2018-01-01

    The high-throughput search paradigm adopted by the newly established caloric materials consortium—CaloriCool®—with the goal to substantially accelerate discovery and design of novel caloric materials is briefly discussed. We begin with describing material selection criteria based on known properties, which are then followed by heuristic fast estimates, ab initio calculations, all of which has been implemented in a set of automated computational tools and measurements. We also demonstrate how theoretical and computational methods serve as a guide for experimental efforts by considering a representative example from the field of magnetocaloric materials.

  7. Detection of low caloric power of coal by pulse fast-thermal neutron analysis

    International Nuclear Information System (INIS)

    Gu De-shan; Sang Hai-feng; Qiao Shuang; Liu Yu-ren, Liu Lin-mao; Jing Shi-wei; Chinese Academy of Sciences, Changchun

    2004-01-01

    Analysis method and principle of pulse fast-thermal neutron analysis (PFTNA) are introduced. A system for the measurement of low caloric power of coal by PFTNA is also presented. The 14 MeV pulse neutron generator and BGO detector and 4096 MCA were applied in this system. A multiple linear regression method applied to the data solved the interferential problem of multiple elements. The error of low caloric power between chemical analysis and experiment was less than 0.4 MJ/kg. (author)

  8. Second Law Violation By Magneto-Caloric Effect Adiabatic Phase Transition of Type I Superconductive Particles

    Directory of Open Access Journals (Sweden)

    Peter Keefe

    2004-03-01

    Full Text Available Abstract: The nature of the thermodynamic behavior of Type I superconductor particles, having a cross section less than the Ginzburg-Landau temperature dependent coherence length is discussed for magnetic field induced adiabatic phase transitions from the superconductive state to the normal state. Argument is advanced supporting the view that when the adiabatic magneto-caloric process is applied to particles, the phase transition is characterized by a decrease in entropy in violation of traditional formulations of the Second Law, evidenced by attainment of a final process temperature below that which would result from an adiabatic magneto-caloric process applied to bulk dimensioned specimens.

  9. 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

  10. Predicción de la generación interna volumétrica de calor y la capacidad calorífica durante un tratamiento electromagnético del material usando algoritmos híbridos

    Directory of Open Access Journals (Sweden)

    Edgar García-Morantes

    2018-01-01

    Full Text Available Este trabajo considera la estimación de la generación interna volumétrica de calor y la capacidad calorífica de una muestra esférica sólida calentada por un campo electromagnético homogéneo variante en el tiempo. Para tal fin, la estrategia numérica soluciona el correspondiente problema inverso. Tres formas funcionales (lineal, senoidal y exponencial para el campo electromagnético fueron considerados. Ruido blanco fue agregado al perfil de temperatura teórica (i.e. la solución del problema directo para simular una situación más realística. La temperatura se pretendió que fuera leída por cuatro sensores. El problema inverso fue solucionado a través de tres diferentes enfoques: usando un optimizador tradicional, usando técnicas modernas y usando una mezcla de ambos. En el primer caso, usamos un algoritmo determinístico tradicional como lo es el de Levenberg-Marquardt (LM. En el segundo, consideramos tres metaheurísticos estocásticos: El Algoritmo de optimización de la espiral (SOA, la Búsqueda en vórtice (VS, y el método de atracción ponderada (WAM. Para el caso final, proponemos híbridos entre el LM y los algoritmos metahehurísticos. Los resultados muestran que LM converge a la solución esperada solo si las condiciones iniciales (IC están dentro de un rango limitado. Por otra parte, los metaheurísticos convergen en un amplio rango de IC pero muestra baja precisión. Los enfoques híbridos convergen y mejoran la precisión obtenida con los metaheurísticos. La diferencia entre los valores esperados y obtenidos, así como, los errores RMS son reportados y comparados para los tres métodos.

  11. 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

  12. 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

  13. Paciente con esquizofrenia tratado con ziprasidona + clozapina

    Directory of Open Access Journals (Sweden)

    Pol Yanguas E.

    2013-05-01

    Full Text Available P es un paciente diagnosticado de esquizofrenia, sigue en un piso tutelado un programa de rehabilitación, está medicado con clozapina 500 mg/día y ziprasidona 280 mg/ día. Padece hipercolesterolemia, tabaquismo y sus hábitos alimenticios no son buenos. La medicación que utiliza desde 2007 hasta ahora se refleja en la tabla 1. El último tratamiento se le introdujo el 7 de agosto de 2012, habiendo presentado un electro cardiograma (ECG normal, pero con ligera taquicardia ventricular y prolactinemia de 44,8 ng/ml (valores normales: 2-18 ng/ml.

  14. Impact of caloric and dietary restriction regimens on markers of health and longevity in humans and animals: a summary of available findings

    OpenAIRE

    Trepanowski, John F; Canale, Robert E; Marshall, Kate E; Kabir, Mohammad M; Bloomer, Richard J

    2011-01-01

    Abstract Considerable interest has been shown in the ability of caloric restriction (CR) to improve multiple parameters of health and to extend lifespan. CR is the reduction of caloric intake - typically by 20 - 40% of ad libitum consumption - while maintaining adequate nutrient intake. Several alternatives to CR exist. CR combined with exercise (CE) consists of both decreased caloric intake and increased caloric expenditure. Alternate-day fasting (ADF) consists of two interchanging days; one...

  15. 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.

  16. Impact of caloric intake in critically ill patients with, and without, refeeding syndrome: A retrospective study.

    Science.gov (United States)

    Olthof, Laura E; Koekkoek, W A C Kristine; van Setten, Coralien; Kars, Johannes C N; van Blokland, Dick; van Zanten, Arthur R H

    2017-08-10

    Refeeding syndrome comprises metabolic disturbances that occur after the reintroduction of feeding after prolonged fasting. Standard care consists of correcting fluid and electrolytes imbalances. Energy intake during refeeding syndrome is heavily debated. This study addresses the effect of caloric intake on outcome during the management of refeeding syndrome. A retrospective study among critically ill invasive mechanically ventilated patients admitted for >7 days to a medical-surgical ICU. Refeeding syndrome was diagnosed by the occurrence of new onset hypophosphatemia (refeeding syndrome were compared and subgroup analysis on energy intake within the refeeding population was performed for the duration of survival. Of 337 enrolled patients, 124 (36.8%) developed refeeding syndrome and 213 patients (63.2%) maintained normal serum phosphate levels. Between the two groups, no statistical significant differences in clinical outcomes were observed. Within the refeeding syndrome group, a reduced 6-month mortality risk for low caloric intake (Refeeding syndrome is common among prolonged mechanically ventilated critically ill patients, however not predictable by baseline characteristics. Among patients that develop refeeding syndrome low caloric intake was associated with a reduction in 6-month mortality risk. This effect was not seen in patients without refeeding syndrome. Findings support caloric restriction in refeeding syndrome during critical illness. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  17. Tema 4. Calor y temperatura (Guía del tema)

    OpenAIRE

    Beléndez Vázquez, Augusto

    2010-01-01

    Guía del "Tema 4. Calor y temperatura" de la asignatura "Fundamentos Físicos de la Ingeniería I" del "Grado en Ingeniería en Sonido e Imagen" impartido en la Escuela Politécnica Superior de la Universidad de Alicante.

  18. Caloric restriction lowers endocannabinoid tonus and improves cardiac function in type 2 diabetes

    NARCIS (Netherlands)

    Eyk, van H.J.; Schinkel, van L.D.; Kantae, V.; Dronkers, C.E.A.; Westenberg, J.J.M.; Roos, de A.; Lamb, H.J.; Jukema, J.W.; Harms, A.C.; Hankemeier, T.; Stelt, van der M.; Jazet, I.M.; Rensen, P.C.N.; Smit, J.W.A.

    2018-01-01

    Background/ObjectivesEndocannabinoids (ECs) are associated with obesity and ectopic fat accumulation, both of which play a role in the development of cardiovascular disease (CVD) in type 2 diabetes (T2D). The effect of prolonged caloric restriction on ECs in relation to fat distribution and cardiac

  19. Effect of solids, caloric content on dual-phase gastric emptying

    Energy Technology Data Exchange (ETDEWEB)

    Van Den Maegdenbergh, V.; Urbain, J.L.; Siegel, J.A.; Mortelmans, L.; De Roo, M. (Univ. Hospital Gasthuisberg, Leuven (Belgium) Temple Univ. Hospital, Philadelphia, PA (USA))

    1990-03-01

    The dual-phase gastric emptying technique is routinely employed to determine the differential emptying of solids and liquids in a wide spectrum of gastrointestinal diseases. Composition, acidity, volume, caloric density, physical form and viscosity of the test means have been shown to be important determinants for the quantitative evaluation of gastric emptying. In this study, the authors have evaluated the effect of increasing the caloric content of the solid portion of a physiologic test mean on both solid and liquid emptying kinetics in health male volunteers. They observed that increasing solid caloric content delayed emptying of both solids and liquids. For the solid phase, the delay was accounted for by a longer lag phase and decrease in emptying rate; for liquids a longer emptying rate was also obtained. They conclude that modification of the caloric content of the solid portion of a meal not only affects the emptying of the solid phase but also alters the emptying of the liquid component of the meal.

  20. 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)

  1. Thermoregulatory, Cardiovascular, and Metabolic Responses to Mild Caloric Restriction in the Brown Norway Rat

    Science.gov (United States)

    Caloric restriction (CR) has been demonstrated to prolong the life span of a variety of species. CR-induced reduction in core temperature (Tc) is considered a key mechanism responsible for prolonging life span in rodents; however, little is known on the regulation of CR-induced h...

  2. Caloric variability of Corbicula fluminea (Mollusca, Bivalvia in Rosana Reservoir, Brazil

    Directory of Open Access Journals (Sweden)

    Yara Moretto Bagatini

    2007-01-01

    Full Text Available The purpose of the present study was to investigate temporal and longitudinal variation of caloric density of Corbicula fluminea in Rosana Reservoir. Significant differences concerning the caloric density of C. fluminea were observed throughout the year at the three reservoir sites. The caloric density variation during the year was probably related to reproductive activity, which demanded higher allocation of energy in certain period. The food source used by this species might be an important factor in the caloric value temporal and spatial variation of C. fluminea in Rosana Reservoir.O objetivo deste estudo foi investigar a variação temporal e longitudinal da densidade calórica de C. fluminea no reservatório de Rosana. Diferenças significativas na densidade calórica de C. fluminea foram observadas ao longo do ano e nas três estações do reservatório. A variação na densidade calórica de C. fluminea, durante o ano, provavelmente foi relacionada à atividade reprodutiva, que exige uma maior alocação de energia em determinado período. O recurso alimentar utilizado por esta espécie pode ser um importante fator na variação temporal e espacial do valor calórico de C. fluminea no reservatório de Rosana.

  3. Sensitivity evaluation in air and water caloric stimulation of the vestibular organs using videonystagmography.

    Science.gov (United States)

    Jałocha-Kaczka, Anna; Pietkiewicz, Piotr; Zielińska-Bliźniewska, Hanna; Miłoński, Jarosław; Olszewski, Jurek

    2014-01-01

    The aim of the study was to compare air and water caloric stimulation of the vestibular organs using videonystagmography (VNG). The study covered 18 women aged 21-63 and 11 men aged 21-74 years hospitalized at the ENT, without complaints for vertigo and/or balance disorders. The alternate binaural bithermal caloric test with cool 30°C and warm 44°C air or water irrigations (after 2h interval for the recordings) with the use of VNG was done. All parameters of air and water vestibular caloric stimulations, assessed in the VNG, differed significantly but were within the normal range. The research showed a statistically significant difference between canal paresis but only for the left ear at 30°C and 44°C. Absolute directional preponderance, relative directional preponderance, vestibular excitability, slow component velocity, frequency were different statistically for both ears at both temperatures. Our study showed that both air and water caloric stimulations were able to distinguish physiological and impaired vestibular function. The obtained results showed statistically higher response for water than air stimulation. Copyright © 2014 Polish Otorhinolaryngology - Head and Neck Surgery Society. Published by Elsevier Urban & Partner Sp. z.o.o. All rights reserved.

  4. Health interest modulates brain reward responses to a perceived low-caloric beverage in females.

    Science.gov (United States)

    van Rijn, Inge; Wegman, Joost; Aarts, Esther; de Graaf, Cees; Smeets, Paul A M

    2017-01-01

    Health labels are omnipresent in the supermarket. Such labels give rise to expectations about the product experience and may change flavor perception and perceived reward value. Consumers vary in their degree of health interest and may be differentially affected by such labels. However, how health interest influences neural reward responses to anticipation and receipt of heath-labeled foods is not known. This study assessed to what extent brain responses induced by anticipation and receipt of a beverage with different levels of perceived caloric content are associated with health interest. Twenty-five females completed an fMRI motivational taste-task in which they were presented with a low-caloric cue or a high-caloric cue and subsequently worked for sips of lemonade by moving a joystick. If they responded correctly and in time, they received the lemonade as a reward. Because of the 2 cue types, participants believed they were receiving 2 different lemonades, a high-caloric (HC-receipt) and a low-caloric (LC-receipt) one. Health interest was assessed with the General health interest subscale of the Health and Taste Attitude Scales. Health interest scores correlated significantly (r = .65) with LC-versus HC-receipt activation in the dorsal striatum (putamen), a region involved in encoding food reward. These findings suggest that the reward value of a healthy product compared to its unhealthy counterpart increases with health interest. This provides more insight into the working mechanism of government campaigns that focus on increasing health interest to encourage the formation of healthy eating habits. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  5. Focos de Calor na Mata Atlântica do Estado do Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Sara dos Santos Clemente

    Full Text Available Resumo O estudo avaliou a ocorrência de focos de calor nos remanescentes da Mata Atlântica no estado do Rio de Janeiro, sob o aspecto climático. As informações obtidas da base de dados BDQueimadas, do período de junho de 1998 a dezembro de 2015, sofreram estatística descritiva, exploratória e paramétrica. As maiores ocorrências de focos de calor foram registradas nos meses de agosto, setembro e outubro e, os anos com os maiores registros foram nos ciclos 2010/2011 (16,06% e 2014/2015 (41, 24%, ambos somaram 57,30% da série temporal, referente a La Niña e El Niño nas categorias forte e fraco. O teste paramétrico mostrou uma repetição dos meses de abril e junho nos anos avaliados na série temporal de focos de calor. As regiões de Governo Centro-Sul Fluminense e Médio Paraíba registraram os maiores registros de focos de calor, segundo a avaliação espacial. Nossos resultados demonstram que o acesso a uma base gratuita de dados permite a prevenção de danos causados pelas queimadas e incêndios. Com a evolução dos sensores de temperatura e de algoritmos de tratamento de dados, será possível diferenciar os focos de calor que representam incêndios e queimadas daqueles que indicam, por exemplo, atividade de indústrias.

  6. The comparative effect of fasting with and without caloric restriction in Rat on oxidative stress parameters

    Directory of Open Access Journals (Sweden)

    Nurina Tyagita

    2016-09-01

    Full Text Available Introduction: Fasting, like Islamic Ramadan Fasting, has been associated with health benefits. Islamic Ramadan fasting, a form of caloric restriction (CR or alternate day fasting that. Studies suggest a comparable effect of ADF and caloric restriction. Despite the fact that fasting can be considered as a form of dietary restriction, fasters tend to have difficulty to reduce their food intake during non-fasting period by overeating leading to the excessive calorie intake. To compare the effect of fasting with and without caloric restriction in Sprague Dawley rats. Methods: The rats were assigned to one of three groups: ADF with 70 % calorie intake (30% CR, ADF with 100 % calorie intake (0% CR, and ADF with 140 % calorie intake (excessive calorie intake and AL (fed ad libitum. All groups were subjected to 6 hour fasting per day (9 a.m. until 3 p.m. or 15 days. The plasma sample was taken for MDA level assessment. Urinary 8-oxodG levels were determined by using ELISA. Results: ADF with 30% calorie restriction (F70 group had the lowest MDA level. Measurement of 8-oxodG level showed that group F70 had the highest production of 8-oxodG. There was an inverse relationship between MDA level and 8-oxodG level meaning the lower MDA level, the lower 8-oxodG levels were produced. Conclusion: ADF fasting with 30% caloric restriction reduce the MDA level but increase 8-oxodG levels. This study suggest the beneficial effect of fasting requires decrease in overall caloric intake.

  7. Beneficial Effects of Caloric Restriction on Chronic Kidney Disease in Rodent Models: A Meta-Analysis and Systematic Review.

    Directory of Open Access Journals (Sweden)

    Xiao-Meng Xu

    Full Text Available Numerous studies have demonstrated the life-extending effect of caloric restriction. It is generally accepted that caloric restriction has health benefits, such as prolonging lifespan and delaying the onset and progression of CKD in various species, especially in rodent models. Although many studies have tested the efficacy of caloric restriction, no complete quantitative analysis of the potential beneficial effects of reducing caloric intake on the development and progression of CKD has been published.All studies regarding the relationship between caloric restriction and chronic kidney diseases were searched in electronic databases, including PubMed/MEDLINE, EMBASE, Science Citation Index (SCI, OVID evidence-based medicine, Chinese Bio-medical Literature and Chinese science and technology periodicals (CNKI, VIP, and Wan Fang. The pooled odds ratios (OR and 95% confidence intervals (95% CI were calculated by using fixed- or random-effects models.The data from 27 of all the studies mentioned above was used in the Meta analysis. Through the meta-analysis, we found that the parameter of blood urea nitrogen, serum creatinine and urinary protein levels of the AL group was significant higher than that of the CR group, which are 4.11 mg/dl, 0.08mg/dl and 33.20mg/kg/24h, respectively. The incidence of the nephropathy in the caloric restriction (CR group was significantly lower than that in the ad libitum-fed (AL group. We further introduced the subgroup analysis and found that the effect of caloric restriction on the occurrence of kidney disease was only significant with prolonged intervention; the beneficial effects of CR on the 60%-caloric-restriction group were greater than on the less-than-60%-caloric-restriction group, and caloric restriction did not show obvious protective effects in genetically modified strains. Moreover, survival rate of the caloric restriction group is much higher than that of the ad libitum-fed (AL group.Our findings

  8. 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.

  9. Determinación de los coeficientes de convección de calor en el flujo radial a través de un lecho de empaque de polietileno

    Directory of Open Access Journals (Sweden)

    Luís Patiño

    2008-09-01

    Full Text Available Se presenta una metodología teórico-experimental para determinar los coeficientes intersticiales de transferencia de calor pro-medio en el flujo radial de agua a través de un lecho de empaque de polietileno donde el fluido no está en equilibrio térmico con la fase sólida. Los coeficientes de transferencia de calor se obtienen a través del Single Blow Transient Method combinando los resultados experimentales en un banco de ensayo con las soluciones numéricas del modelo matemático. El sistema de ecua-ciones diferenciales parciales generado en el modelo matemático es resuelto a través de una metodología numérica basada en el método de volúmenes finitos. Las pruebas experimentales y las soluciones numéricas se realizaron para diferentes valores de velocidad superficial del fluido a la entrada del lecho y para diversos valores de porosidad del medio, obteniéndose que los números de Nusselt aumentan al incrementarse el número de Reynolds, y de igual manera, también aumentan al disminuir la porosidad del medio, observándose valores de Nusselt hasta de 2,8 para una porosidad de 0,375 y un número de Reynolds de 650.

  10. Estudio termodinámico de una planta de ciclo combinado con turbina de gas y pre-diseño del HRSG

    OpenAIRE

    Martín Díaz, Carlos Daniel

    2015-01-01

    Dentro del gran alcance que se puede dar a los estudios de plantas de ciclos combinados, el presente estudio se centra en analizar un ciclo combinado convencional con turbina de gas, y en condiciones de diseño. En concreto, se trata de realizar un análisis termodinámico de un ciclo combinado en configuración monoeje 1x1 con recalentamiento y tres niveles de presión, con turbina de gas refrigerada por sistema vapor-aire y posteriormente un análisis de transferencia de calor en los intercamb...

  11. Factores de riesgo ambientales y componentes del síndrome metabólico en adolescentes con exceso de peso

    Directory of Open Access Journals (Sweden)

    Nora Elena Múnera

    2012-03-01

    Conclusiones. Los factores de riesgo ambientales asociados con los componentes del síndrome metabólico en este estudio fueron el mayor consumo de calorías, carbohidratos complejos y simples, todos relacionados directamente con el IMC; por el contrario, el nivel de actividad física, los antecedentes familiares y los personales no mostraron ninguna asociación. El síndrome metabólico sólo se presentó en jóvenes con obesidad.   DOI: http://dx.doi.org/10.7705/biomedica.v32i1.595

  12. 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

  13. PRE-COMPACTACIÓN Y ACONDICIONAMIENTO ORGANICO PARA LA RECULTIVACIÓN DE UN SUELO DE TEXTURA GRUESA (TYPIC XEROCHREPTS) DISTURBADO POR EXTRACCIÓN DE ÁRIDOS

    OpenAIRE

    Seguel, Oscar; Rodríguez, Natalia; Soto, Lely; Homer, Ian; Benavides, Carlos; Casanova, Manuel; Haberland, Julio

    2017-01-01

    RESUMEN La extracción de áridos genera un daño a la estructura del suelo superficial, disminuyendo su capacidad de soporte. Con el objeto de recuperar un suelo agrícola (Typic Xerochrepts, franco arenoso) disturbado por extracción de arenas sub-superficiales, se desarrolló un estudio en la zona central de Chile, en macetas de 20 L, estableciendo tratamientos con dos factores: pre-compactación (sin y con dos niveles crecientes) e incorporación de enmienda orgánica (cama broiler en dosis de 0, ...

  14. The CaloRIC ASIC: Signal Processing for High Granularity Calorimeter

    International Nuclear Information System (INIS)

    Royer, L; Manen, S; Soumpholphakdy, X; Bonnard, J; Gay, P

    2013-01-01

    A readout ASIC called CaloRIC, has been developed to fulfil the signal processing requirements for the Silicon-Tungsten (Si-W) electromagnetic calorimeter of the International Linear Collider (ILC). This ASIC performs the complete processing of the signal delivered by the Si-PIN diode of the detector: charge sensitive amplification, shaping, analog memorization and digitization. Measurements show a global integral non-linearity better than 0.2% for low energy particles, and limited to 2% for high energy particles. The measured Equivalent Noise Charge (ENC) is evaluated at 0.6 fC, which corresponds to 1/6 times the signal released by a Minimum Ionizing Particle (MIP). With the timing sequence of the ILC, the power consumption of the complete channel is evaluated at 43 μW using a power pulsing. A new ASIC (CaloRIC 4 ch) with four improved readout channels has been designed and is ready for manufacturing.

  15. Effect of the stringency of conditions on caloric test results in healthy subjects.

    Science.gov (United States)

    Krstulovic, Claudio; Tulsidas Mahtani, Bharti; Atrache Al Attrache, Nabil; Pérez-Garrigues, Herminio

    The caloric test is widely used to assess vestibular function, but the conditions in which it is performed can vary. Caloric nystagmus obtained in 57 healthy subjects were compared: 24 subjects studied in ideal conditions and 33 subjects in non-ideal conditions. A statistically significant decrease in the slow phase velocity of the 4 irrigations performed on the subjects in non-ideal conditions was observed. This must be considered, especially in subjects with suspected bilateral involvement. Stringent conditions reduce the risk of misdiagnosis with bilateral deficit. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

  16. 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...... function with regard to capacity of attention. In conclusion, we find evidence to support that habitual physical activity may prevent pathophysiological symptoms associated with diet-induced obesity....... 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...

  17. Influence of meal weight and caloric content on gastric emptying of meals in man

    International Nuclear Information System (INIS)

    Moore, J.G.; Christian, P.E.; Brown, J.A.; Brophy, C.; Datz, F.; Taylor, A.; Alazraki, N.

    1984-01-01

    This study was designed to assess the relative influence of meal weight and caloric content on gastric emptying of liquid and solid meals in man. A dual radioisotopic method which permits noninvasive and simultaneous measurement of liquid- and solid-phase emptying by external gamma camera techniques was employed. Nine healthy volunteer subjects ingested 50-, 300-, and 900-g lettuce and water meals adjusted to either 68, 208, or 633 kcal with added salad oil. The following observations were made: (1) absolute emptying rates (grams of solid food emptied from the stomach per minute) increased directly and significantly with meal weight; (2) increasing meal total caloric content significantly slowed solid food gastric emptying but did not overcome the enhancing effect of meal weight; and (3) liquid emptying rates were uninfluenced by meal total kcal amount

  18. Is the caloric curve a robust signal of the phase transition in hot nuclei?

    International Nuclear Information System (INIS)

    Vient, E.

    2016-01-01

    The richness of the data set, collected by the INDRA Collaboration during the last twenty years, enabled to build a set of caloric curves for nuclei of various sizes, by using, for the first time, a single experimental set-up and a single experimental protocol. We will therefore present the different caloric curves (E ∗ −T) obtained by a new calorimetry, for Quasi-Projectiles produced by symmetric or quasi symmetric reactions at different incident energies (Au+Au, Xe+Sn, Ni+Ni). For all these systems, a clear change of the de-excitation process of hot nuclei is observed but this one is neither a plateau nor a back-bending, but a sudden change of slope.

  19. Influence of meal weight and caloric content on gastric emptying of meals in man

    Energy Technology Data Exchange (ETDEWEB)

    Moore, J.G.; Christian, P.E.; Brown, J.A.; Brophy, C.; Datz, F.; Taylor, A.; Alazraki, N.

    1984-06-01

    This study was designed to assess the relative influence of meal weight and caloric content on gastric emptying of liquid and solid meals in man. A dual radioisotopic method which permits noninvasive and simultaneous measurement of liquid- and solid-phase emptying by external gamma camera techniques was employed. Nine healthy volunteer subjects ingested 50-, 300-, and 900-g lettuce and water meals adjusted to either 68, 208, or 633 kcal with added salad oil. The following observations were made: (1) absolute emptying rates (grams of solid food emptied from the stomach per minute) increased directly and significantly with meal weight; (2) increasing meal total caloric content significantly slowed solid food gastric emptying but did not overcome the enhancing effect of meal weight; and (3) liquid emptying rates were uninfluenced by meal total kcal amount.

  20. Hacia un modelo dinámico para la isla de calor urbana de Madrid = Towards a Dynamic Model for the Urban Heat Island of Madrid.

    Directory of Open Access Journals (Sweden)

    Miguel Núñez Peiró

    2016-04-01

    Full Text Available Esta investigación se enmarca dentro del proyecto MODIFICA (modelo predictivo - Edificios - Isla de Calor Urbano, financiado por el Programa de I + D + i Orientada a los Retos de la sociedad 'Retos Investigación' de 2013. Está dirigido a desarrollar un modelo predictivo de eficiencia energética para viviendas, bajo el efecto de isla de calor urbano (AUS con el fin de ponerla en práctica en la evaluación de la demanda de energía real y el consumo en las viviendas. A pesar de los grandes avances que se han logrado durante los últimos años en el rendimiento energético de edificios, los archivos de tiempo utilizados en la construcción de simulaciones de energía se derivan generalmente de estaciones meteorológicas situadas en las afueras de la ciudad. Por lo tanto, el efecto de la Isla de Calor Urbano (ICU no se considera en estos cálculos, lo que implica una importante falta de precisión. Centrado en explorar cómo incluir los fenómenos ICU, el presente trabajo recopila y analiza la dinámica por hora de la temperatura en diferentes lugares dentro de la ciudad de Madrid. Abstract This research is framed within the project MODIFICA (Predictive model - Buildings - Urban Heat Island, funded by Programa de I+D+i orientada a los retos de la sociedad 'Retos Investigación' 2013. It is aimed at developing a predictive model for dwelling energy performance under the Urban Heat Island (UHI effect in order to implement it in the evaluation of real energy demand and consumption in dwellings. Despite great advances on building energy performance have been achieved during the last years, weather files used in building energy simulations are usually derived from weather stations placed in the outskirts of the city. Hence, Urban Heat Island (UHI effect is not considered in this calculations, which implies an important lack of accuracy. Focused on exploring how to include the UHI phenomena, the present paper compiles and analyses the hourly dynamics

  1. Videojuego con Realidad Virtual

    OpenAIRE

    González Mora, César

    2017-01-01

    El objetivo del proyecto es el desarrollo de un videojuego deportivo que utilice realidad mixta. El videojuego se podrá utilizar con dispositivos de tipo cardboard, y utilizará realidad aumentada para la interacción del jugador con el videojuego. En el desarrollo se utilizará el motor Unity para conseguir una aplicación multiplataforma, y la librería Vuforia para implementar realidad mixta.

  2. Sistemas integrados con Arduino

    OpenAIRE

    EL YAKOUTI, MOHAMMED

    2017-01-01

    Design of a robot prototype remotely controllable from Bluetooth using Arduino. Control and testing of sensors and events interacting with Arduino and Bluetooth. Diseño de un prototipo de robot controlable remotamente con Bluetooth utilizando Arduino. Control y verificación de los sensores y eventos que interactúan mediante el Arduino y el Bluetooth. El Yakouti, M. (2017). Sistemas integrados con Arduino. http://hdl.handle.net/10251/89274. TFGM

  3. 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.

  4. Al calor de la masculinidad. Clima, migración y normativas de género en la Costa de Hermosillo, Sonora

    Directory of Open Access Journals (Sweden)

    José Eduardo Calvario Parra

    2017-01-01

    Full Text Available En este estudio sobre migrantes jornaleros(as agrícolas en la Costa de Hermosillo, Sonora, se presenta una primera aproximación analítica y descriptiva respecto a la relación entre clima y masculinidad en el noroeste de México. A través de un enfoque metodológico cualitativo, por medio de entrevistas semiestructuradas y observaciones de campo, se explora el vínculo entre las normativas masculinas y las prácticas o discursos relacionados con el cuidado ante el calor natural excesivo. La conclusión es que las condiciones de vulnerabilidad estructural que viven los/as trabajadores/as agrícolas están acompañadas con ideologías de género, que en situaciones determinadas se vuelven cruciales para tomar la decisión de cuidarse de las temperaturas altas o de no hacerlo.

  5. Caloric restriction in lean and obese strains of laboratory rat: effects on body composition, metabolism, growth and overall health

    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. Effects of Moderate Aerobic Exercise Combined With Caloric Restriction on Circulating Estrogens and IGF-I in Premenopausal Women

    National Research Council Canada - National Science Library

    Williams, Nancy I

    2004-01-01

    ... the primary prevention of breast cancer in women. This study has examined the effects of exercise training combined with caloric restriction, resulting in weight loss, on two hormonal biomarkers for breast cancer i.e...

  7. 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

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

    OpenAIRE

    Elodie eChiarovano; Pierre-Paul eVidal; Christophe eMagnani; Georges eLamas; Ian S Curthoys; Catherine eDe Waele; Catherine eDe Waele

    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 separated in two groups: 10 seniors reporting postural instabili...

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

    OpenAIRE

    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 in...

  10. Second Law Violation By Magneto-Caloric Effect Adiabatic Phase Transition of Type I Superconductive Particles

    OpenAIRE

    Keefe, Peter

    2004-01-01

    Abstract: The nature of the thermodynamic behavior of Type I superconductor particles, having a cross section less than the Ginzburg-Landau temperature dependent coherence length is discussed for magnetic field induced adiabatic phase transitions from the superconductive state to the normal state. Argument is advanced supporting the view that when the adiabatic magneto-caloric process is applied to particles, the phase transition is characterized by a decrease in entropy in violation of tradi...

  11. Caloric compensation in preschool children: Relationships with body mass and differences by food category.

    Science.gov (United States)

    Carnell, S; Benson, L; Gibson, E L; Mais, L A; Warkentin, S

    2017-09-01

    Maintaining a healthy weight may involve compensating for previously consumed calories at subsequent meals. To test whether heavier children demonstrated poorer caloric compensation across a range of conditions, and to explore whether compensation failure was the result of inadequate adjustment of overall intake or specific over-consumption of highly palatable, high energy-density 'junk' foods, we administered two compensation tests to a sample of 4-5 y olds. For Test A, preloads varied only in carbohydrate content and were organoleptically indistinguishable (200 ml orange-flavored beverage [0 kcal vs. 200 kcal]). For Test B, the preloads varied substantially in both macronutrient composition and learned gustatory cues to caloric content (200 ml water [0 kcal] vs. 200 ml strawberry milkshake [200 kcal]). Each preload was followed 30 min later by a multi-item ad-libitum meal containing junk foods (chocolate cookies, cheese-flavored crackers) and core foods (fruits and vegetables, bread rolls, protein foods). Testing took place at the children's own school under normal lunch-time conditions. Children were weighed and measured. Caloric compensation occurred in both tests, in terms of total, junk and core food intake (RMANOVA, all p food intake (RMANOVA preload-by-weight group interaction p foods. Our results suggest that caloric compensation is consistently poorer in heavier children, and that overweight/obese children's preferences for junk foods may overwhelm intake regulation mechanisms within meals containing those foods. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Caloric beverages were major sources of energy among children and adults in Mexico, 1999-2012.

    Science.gov (United States)

    Stern, Dalia; Piernas, Carmen; Barquera, Simon; Rivera, Juan A; Popkin, Barry M

    2014-06-01

    Mexico, with 1 of the highest obesity prevalences in the world, instituted a 10% excise tax for any sugar-sweetened beverage (SSB) starting on 1 January 2014. Understanding the recent patterns and trends in beverage intake and sales in Mexico provides both background and baseline data for the importance of SSBs and other beverages in the Mexican diet. We analyzed a single 24-h dietary recall from 2 nationally representative surveys: the Mexican Nutrition Survey 1999 (n = 6049) and the National Health and Nutrition Survey 2012 (n = 10,343). To describe trends and patterns in beverages, we calculated the volume and energy intake per capita and per consumer and the proportion of consumers of each beverage group in each survey. A commercial sales dataset was used to describe beverage sales trends from 1999 to 2012. From 1999 to 2012, total daily energy from beverages increased among children aged 5-11 y (+45.3 kcal), females aged 12-19 y (+57.3 kcal), and adult females aged 20-49 y (+96.4 kcal) (P energy intake per capita in children aged 1-19 y and adults aged ≥20 y, respectively. In 2012, flavored milk beverages, caloric soda, and high-fat milk were the top 3 major contributors to total daily energy intake per capita in all children aged 1-19 y. Caloric soda, caloric coffee/tea, and agua fresca were the top 3 major energy contributors in adults aged ≥20 y. From 1999 to 2012, sales of soda, fruit-flavored drinks, and flavored waters increased. In conclusion, consumption of several beverages with added sugars increased among children and adult females in Mexico. Because caloric soda is currently 1 of the top beverages consumed, a 10% tax on SSBs might help to significantly reduce added sugars intake in Mexico. © 2014 American Society for Nutrition.

  13. The influence of caffeine on calorics and cervical vestibular evoked myogenic potentials (cVEMPs).

    Science.gov (United States)

    McNerney, Kathleen; Coad, Mary Lou; Burkard, Robert

    2014-03-01

    Prior to undergoing vestibular function testing, it is not uncommon for clinicians to request that patients abstain from caffeine 24 hr prior to the administration of the tests. However, there is little evidence that caffeine affects vestibular function. To evaluate whether the results from two tests commonly used in a clinical setting to assess vestibular function (i.e., calorics and the cervical vestibular evoked myogenic potential [cVEMP]) are affected by caffeine. Subjects were tested with and without consuming a moderate amount of caffeine prior to undergoing calorics and cVEMPs. Thirty young healthy controls (mean = 23.28 yr; females = 21). Subjects were excluded if they reported any history of vestibular/balance impairment. The Variotherm Plus Caloric Irrigator was used to administer the water, while the I-Portal VNG software was used to collect and analyze subjects' eye movements. The TECA Evoked Potential System was used for the cVEMP stimulus presentation as well as for the data collection. During cVEMP collection, subjects were asked to monitor their sternocleidomastoid muscle contraction with a Delsys EMG monitor. IBM SPSS Statistics 20 was used to statistically analyze the results via paired t-tests. Analysis of the data revealed that ingestion of caffeine did not significantly influence the results of either test of vestibular function. The results revealed that a moderate amount of caffeine does not have a clinically significant effect on the results from caloric and cVEMP tests in young healthy adults. Future research is necessary to determine whether similar results would be obtained from individuals with a vestibular impairment, as well as older adults. American Academy of Audiology.

  14. 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.

  15. 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.

  16. Quantifying food intake in socially housed monkeys: social status effects on caloric consumption

    Science.gov (United States)

    Wilson, Mark E.; Fisher, Jeff; Fischer, Andrew; Lee, Vanessa; Harris, Ruth B.; Bartness, Timothy J.

    2008-01-01

    Obesity results from a number of factors including socio-environmental influences and rodent models show that several different stressors increase the preference for calorically dense foods leading to an obese phenotype. We present here a non-human primate model using socially housed adult female macaques living in long-term stable groups given access to diets of different caloric density. Consumption of a low fat (LFD; 15% of calories from fat) and a high fat diet (HFD; 45% of calories from fat) was quantified by means of a custom-built, automated feeder that dispensed a pellet of food when activated by a radiofrequency chip implanted subcutaneously in the animal’s wrist. Socially subordinate females showed indices of chronic psychological stress having reduced glucocorticoid negative feedback and higher frequencies of anxiety-like behavior. Twenty-four hour intakes of both the LFD and HFD were significantly greater in subordinates than dominates, an effect that persisted whether standard monkey chow (13% of calories from fat) was present or absent. Furthermore, although dominants restricted their food intake to daylight, subordinates continued to feed at night. Total caloric intake was significantly correlated with body weight change. Collectively, these results show that food intake can be reliably quantified in non-human primates living in complex social environments and suggest that socially-subordinate females consume more calories, suggesting this ethologically relevant model may help understand how psychosocial stress changes food preferences and consumption leading to obesity. PMID:18486158

  17. Investigation on caloric requirement of biomass pyrolysis using TG-DSC analyzer

    Energy Technology Data Exchange (ETDEWEB)

    He Fang [Institute of Utilization of Biomass, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo, Shandong 255049 (China)]. E-mail: hf@sdut.edu.cn; Yi Weiming [Institute of Utilization of Biomass, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo, Shandong 255049 (China); Bai Xueyuan [Institute of Utilization of Biomass, Shandong University of Technology, No. 12, Zhangzhou Road, Zibo, Shandong 255049 (China)

    2006-09-15

    The caloric requirement of biomass pyrolysis has an important influence on the course of the thermal conversion. However, precise data are difficult to achieve by the current calculation method because of the complexity of the process. A new method for achieving the caloric requirement of the process by integrating the differential scanning calorimetry (DSC) curves was proposed after the simultaneous thermal analyzer (TG-DSC) and DSC curves were investigated. Experiments were conducted for wheat straw, cotton stalk, pine and peanut shell on a Netsch STA 449C analyzer. Powder samples were put into a platinum crucible with a lid on a high accuracy DSC-cp sample holder in the furnace and then heated from ambient temperature up to the maximum temperature of 973 K at the heating rate of 10 K/min in the analyzer. The product gases were swept away by 25 ml/min nitrogen. Mass changes (TG) and calorimetric effects (DSC) were recorded and analyzed. The process was investigated in detail through comparison of the DTG (differential thermogravimetric) and DSC curves of wheat straw. After the water influence in the DSC was eliminated, the relationship of the caloric requirement with the temperature of the aforementioned dry biomass was obtained by integrating the DSC curve. The results showed that 523 kJ, 459 kJ, 646 kJ and 385 kJ were required, respectively, to increase the temperature of 1 kg of dried wheat straw, cotton stalk, pine and peanut from 303 K to 673 K.

  18. CALOR2012 XVth International Conference on Calorimetry in High Energy Physics

    Energy Technology Data Exchange (ETDEWEB)

    Akchurin, Nural .

    2015-05-04

    The International Conferences on Calorimetry in High Energy Physics, or the CALOR series, have always been where the calorimeter experts come together to review the state of calorimetry and bring forth new ideas every two years. The fteenth conference, CALOR2012, in Santa Fe was no exception. Although they were built roughly a decade ago, we are now witnessing the exceptional power of the LHC calorimeters and the crucial role they have been playing in the discovery of the 125 GeV Higgs-like boson. As we ruminate on the coming generation of experiments at the next (linear) collider and on the upgrades at the LHC, we are heartened by the substantial advances we made in calorimetry in the last decade. These advances will certainly help uncover new physics in the years to come, not only at colliders but also in astroparticle experiments that take advantage of natural elements such as air, water, and ice. The proceedings were published by the IOP in Journal of Physics, Vol 404 2011. The conference web site is calor2012.ttu.edu.

  19. Short-Term Caloric Restriction Suppresses Cardiac Oxidative Stress and Hypertrophy Caused by Chronic Pressure Overload.

    Science.gov (United States)

    Kobara, Miyuki; Furumori-Yukiya, Akiko; Kitamura, Miho; Matsumura, Mihoko; Ohigashi, Makoto; Toba, Hiroe; Nakata, Tetsuo

    2015-08-01

    Caloric restriction (CR) prevents senescent changes, in which reactive oxygen species (ROS) have a critical role. Left ventricular (LV) hypertrophy is a risk factor for cardiovascular diseases. We examined whether CR alters cardiac redox state and hypertrophy from chronic pressure overload. Male c57BL6 mice were subjected to ascending aortic constriction (AAC) with ad libitum caloric intake (AL + AAC group) or 40% restricted caloric intake (CR + AAC group). CR was initiated 2 weeks before AAC and was continued for 4 weeks. Two weeks after constriction, AAC increased LV wall thickness, impaired transmitral flow velocity, and augmented myocyte hypertrophy and fibrosis, in association with enhancement of BNP and collagen III expressions in the AL + AAC group. In the AL + AAC group, oxidative stress in cardiac tissue and mitochondria were enhanced, and NADPH oxidase activity and mitochondrial ROS production were elevated. These changes were significantly attenuated in the CR + AAC group. Additionally, in antioxidant systems, myocardial glutathione peroxidase and superoxide dismutase activities were enhanced in the CR + AAC group. Chronic pressure overload increased cardiac oxidative damage, in association with cardiac hypertrophy and fibrosis. Short-term CR suppressed oxidative stress and improved cardiac function, suggesting that short-term CR could be a useful strategy to prevent pressure overload-induced cardiac injury. Copyright © 2015 Elsevier Inc. All rights reserved.

  20. Three-dimensional analysis of post-caloric nystagmus caused by postural change.

    Science.gov (United States)

    Young, Y H; Chiang, C W; Wang, C P

    2001-01-01

    In order to record caloric nystagmus (CN) using three-dimensional videonystagmography (3D VNG) 14 subjects were placed in the supine position with the head tilted up 30 degrees relative to the earth's horizontal plane. After the primary-phase CN had terminated, the subjects were repositioned from a supine to a sitting position, with the head anteflexed 30 degrees for recording the post-caloric nystagmus (PCN). In addition, 8 of the original subjects were placed in the supine position but with the head turned 40 degrees to the left so that the irrigated (right) ear was oriented upwards. After the primary-phase CN had terminated, the subjects were rotated by 180 degrees so that the irrigated ear was oriented downwards to record PCN. The results indicated that both methods successfully provoked horizontal and vertical CN. For torsional CN, the irrigated ear up/down method produced a higher provocation rate (75%) than the supine/sitting method (50%), but the difference was not significant. Comparing the provocation rate of the PCN for the horizontal component revealed that the two methods do not differ significantly. However, when comparing the provocation rates of PCN for the vertical component, the irrigated ear up/down method showed a higher rate (82%) than the supine/sitting method (18%). Thus using 3D VNG coupled with postural change during caloric testing, the horizontal or vertical components of PCN can be successfully provoked.

  1. 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.

  2. Temas de Física para Ingeniería: Temperatura y propagación del calor

    OpenAIRE

    Beléndez Vázquez, Augusto

    1992-01-01

    Acústica, fluidos y termodinámica: "Temperatura y propagación del calor". Introducción. Descripciones macroscópica y microscópica de un sistema. Equilibrio térmico y principio cero de la termodinámica. Termómetros y escala de temperaturas del gas ideal. Dilatación térmica. Propagación del calor.

  3. Activation of the central melanocortin system in rats persistently reduces body and fat mass independently of caloric reduction.

    Science.gov (United States)

    Côté, Isabelle; Green, Sara M; Morgan, Drake; Carter, Christy S; Tümer, Nihal; Scarpace, Philip J

    2018-03-01

    Recent evidence indicate that melanotan II (MTII) reduces body mass independently of caloric reduction. Because MTII induces a transient hypophagia, caloric reduction is still considered a primary mechanism for MTII-mediated body mass loss. To examine the contribution of caloric reduction to long-term body mass loss in response to MTII, we centrally infused MTII or vehicle in ad libitum fed (MTII and Control) animals in comparison with a group of animals that were pair-fed (PF) to the MTII group. Food intake and body mass were recorded daily, and body composition was assessed biweekly. The present study demonstrates that central MTII-mediated body mass loss is only partially mediated by caloric restriction, and the long-term body mass loss is independent of the initial hypophagia. More importantly, central MTII administration induced a rapid but sustained fat mass loss, independently of caloric reduction. MTII-treated animals preserved their lean/fat mass ratio throughout the study, whereas PF animals underwent a transient reduction of lean/fat mass ratio that was only normalized when food intake returned to Control level. In summary, it can be concluded that activation of the central melanocortin system in rats persistently reduces body and fat mass independently of caloric reduction.

  4. Feeding preference of adult females of ribbonfish Trichiurus lepturus through prey proximate-composition and caloric values

    Directory of Open Access Journals (Sweden)

    Vanessa Trindade Bittar

    Full Text Available In the present study we analysed the proximate-composition and caloric values of the preferred prey consumed by ribbonfish, Trichiurus lepturus L. 1758 (adult females, that are distributed in the inner continental shelf from northern Rio de Janeiro State, southeastern Brazil (~22ºS, assessing the potential of nutritional and energetic approach as a tool to understand the feeding selective pattern of this marine top carnivore. The preferred prey of this predator composed of fish co-specifics, Pellona harroweri, Chirocentrodon bleekerianus, Lycengraulis grossidens, Peprilus paru, squid Doryteuthis plei, and shrimp Xiphopenaeus kroyeri were collected from 2007 to 2010 for proximate-composition (water, protein, lipid, ash, and carbohydrate and caloric value analyses. The correspondence analysis showed that protein is the main component in the prey species (61.32% of variance explained, standing out from the other nutrients. Lipid has the highest percentage related to L. grossidens, ash to X. kroyeri and carbohydrate to D. plei. The strong correlations between protein and caloric value (positive and lipid and caloric value (negative indicated that T. lepturus is attending its energy demand through the prey protein content. This work elucidated the feeding preference of adult females of T. lepturus in relation to nutritional and caloric content of their preferred prey. The species showed food selectivity to prey that provide more energy per ingested biomass, so that the feeding events can maximize the predator's caloric gain, which is obtained by a protein-based diet.

  5. 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. Copyright © 2012 Elsevier Ltd. All rights reserved.

  6. Etmoiditis complicada con celulitis orbitaria en un lactante

    Directory of Open Access Journals (Sweden)

    Odette Pantoja Pereda

    Full Text Available Se define la etmoiditis como la inflamación e infección de la mucosa de las celdas etmoidales. Se diagnostica clínicamente con la presencia de edema en el ángulo medial del ojo, que se extiende a las estructuras adyacentes. Estudios imagenológicos son necesarios para verificar la presencia de complicaciones, entre las que se citan el absceso orbitario, subperióstico, epidural, subdural, cerebral, tromboflebitis del seno cavernoso, meningoencefalitis y la muerte del paciente. Streptococcus pneumoniae, Staphylococcus aureus y Haemophilus influenzae son microorganismos frecuentemente responsables de este cuadro. Las complicaciones orbitarias en las etmoiditis, necesitan el diagnóstico y tratamiento precoz para evitar secuelas irreversibles. Se presenta el caso de un lactante masculino, de 1 mes y 26 días de nacido, que ingresa con fiebre, rinorrea serosa y rechazo al alimento. Evolutivamente se constata marcada obstrucción nasal, edema periorbitario izquierdo, rubor, calor, protrusión del globo ocular e irritabilidad, y se diagnostica etmoiditis complicada con celulitis orbitaria. Se realiza tomografía axial computarizada que informa seno etmoidal izquierdo ocupado por contenido de densidad líquida con celularidad (15-25 UH, engrosamiento de partes blandas de la pared interna de la órbita que abomba, comprime y desplaza la musculatura orbitaria, y se extiende al párpado y al ala izquierda de la nariz desviando tabique blando; así como ligera proptosis, y disminución de la densidad ósea de la pared interna de la cavidad orbitaria. Se toma muestra para cultivo y se aísla Staphylococcus aureus meticillin resistente. Se comentan los elementos diagnósticos y su tratamiento, con el objetivo de llamar la atención de los pediatras para lograr el diagnóstico y tratamiento oportuno.

  7. 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.

  8. Giochiamo con i robot

    Directory of Open Access Journals (Sweden)

    Andrea Bonarini

    2009-01-01

    Full Text Available "Giochiamo con i robot" e' un laboratorio interattivo per grandi e piccini realizzato per l'edizione 2007 del Festival della Scienza di Genova. Lungo un percorso che va dalla telerobotica alla robotica evolutiva, il laboratorio sviluppa il tema di dare intelligenza ai robot. Questo percorso, le cui tappe sono le varie installazioni, si conclude nella "bottega" dove e' possibile costruire e programmare i propri robot o smontare e modificare quelli esposti durante il percorso didattico. I visitatori sono coinvolti in attivita' ludiche grazie alle quali possonoentrare in contatto con alcune delle idee potenti della robotica,

  9. disegnare con ... Alberto Pratelli

    Directory of Open Access Journals (Sweden)

    Roberto Mingucci

    2017-12-01

    Full Text Available Con questa breve intervista ad Alberto Pratelli, (non a caso scelto per aprire questa nuova rubrica intendia-mo inaugurare un dialogo con personalità significati-ve del Disegno di Architettura, che consenta riflessioni dedicate alle sue varie dimensioni, oggi più che mai da approfondire. La suggestione a farlo, viene da un’idea di Pablo Rodri-guez Navarro ed abbiamo quindi pensato di avviarla proprio in questo numero, che Pablo ha accettato di curare su un tema a lui particolarmente caro.

  10. Efecto de la Composición Química del Metal de Aporte y del Calor Aportado Sobre la Microestructura y las Propiedades Mecánicas de Juntas Soldadas de Aceros Inoxidables Dúplex

    Directory of Open Access Journals (Sweden)

    Sebastián Zappa

    Full Text Available Resumen Los aceros inoxidables dúplex poseen una microestructura dual (ferrita y austenita con contenidos aproximadamente iguales y se caracterizan por tener buena soldabilidad, buenas propiedades mecánicas y una alta resistencia a la corrosión generalizada y localizada. Gracias a estas características, estos aceros son los principales materiales a emplear en cañerías con altas exigencias, ampliamente utilizados en varias industrias, principalmente la petroquímica. Dichas propiedades están controladas por la composición química, el equilibrio microestructural y la ausencia de compuestos intermetálicos. El objetivo de este trabajo fue estudiar la influencia de la composición química del metal de aporte y el calor aportado sobre la microestructura y las propiedades mecánicas en juntas soldadas de cañerías de acero inoxidable dúplex. El metal base utilizado fue un acero inoxidable dúplex UNS S31803 de 8” de diámetro y 8,18 mm de espesor y los metales de aporte fueron dos alambres tubulares que depositan aceros inoxidables dúplex y lean dúplex (AWS A5.22: E2209T1-1 y E2209T1-G, mediante el proceso de soldadura semi-automático bajo protección gaseosa, soldados con alto y bajo calor aportado. De cada probeta se extrajeron muestras donde se determinó la composición química, se realizó la caracterización microestructural y se determinaron las propiedades mecánicas (dureza, tracción y Charpy-V.

  11. Introducción al estudio de la transmisión de calor a través de cerramientos en régimen de temperatura variable periódicamente

    Directory of Open Access Journals (Sweden)

    García Arroyo, A.

    1965-12-01

    Full Text Available In the study of heat transmission across outer walls, it is not possible to avoid the fact that external temperature varies periodically. Hence in this paper a theoretical calculation is made of the maximum heat flow across a wall, taking Into account the damping and retardation acting on the heat wave, as it reaches the inner face of the wall. A number of practical numerical applications are given. A number of a priori simplifying hypotheses have been made, which enable a rational and non too complex study of the problem to be made. This has been possible by the use of the Alford, Ryan and Urban equations.Como quiera que, en el estudio de la transmisión de calor a través de muros de cerramiento, no podemos prescindir del hecho de que la temperatura extrema varíe periódicamente en función del tiempo, se efectúa aquí el cálculo teórico del flujo máximo de calor que atraviesa un muro de habitación, considerando la amortiguación y el desfase con que la onda calorífica llega a la cara interior, realizando a continuación algunas aplicaciones numéricas. Para ello hemos de considerar «a priori» algunas hipótesis simplificadoras que nos permitan un estudio racional y no excesivamente complicado del problema planteado, lo que conseguimos sirviéndonos de las ecuaciones de Alford, Ryan y Urban.

  12. Conversando con Oriol Bohigas

    OpenAIRE

    Redondo Domínguez, Ernesto; Moya Sala, Joaquim

    2015-01-01

    [EN] Interview with Oriol Bohigas [ES] Entrevista con Oriol Bohigas Redondo Domínguez, E.; Moya Sala, J. (2015). Conversando con… Oriol Bohigas. EGA. Revista de Expresión Gráfica Arquitectónica. 20(26):22-35. doi:10.4995/ega.2015.4061 22 35 20 26

  13. DR Con o:

    African Journals Online (AJOL)

    which could fall under the Ugandan influence. The con-. flict in the ..... The Congolese people and international community within SADC, the AU ..... ments and make peace among themselves. However, one ... friends overnight.There is a great ...

  14. fertilizada con diferentes abonos

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Elizondo-Salazar

    2007-01-01

    Full Text Available Producción y calidad de la biomasa de morera (Morus alba fertilizada con diferentes abonos. Se llevó a cabo un experimento en la Estación Experimental “Alfredo Volio Mata” de la Universidad de Costa Rica con el fi n de evaluar la aplicación de 150 kg de N/ha/año proveniente de dos abonos orgánicos: lombriabono y compostaje; y de un fertilizante químico, sobre la producción y calidad de la biomasa de morera. El periodo experimental comprendió un ciclo de 12 meses, iniciando en julio del 2003 y fi nalizando en julio del 2004. Se utilizó una plantación de morera de 12 años de establecida con una densidad de siembra de 27.777 plantas/ ha. Se empleó un diseño de bloques completos al azar con cuatro tratamientos: dos abonos orgánicos, nitrato de amonio (33,5% N y un control. Las plantas se podaron a 0,6 m sobre el nivel del suelo al inicio del ensayo. Durante el periodo experimental, las plantas fueron podadas consecutivamente cada 90 días. Las hojas y los tallos fueron separados y analizados para determinar el contenido de materia seca y proteína cruda. La producción de materia seca fue 23% superior y el contenido de proteína cruda fue signifi cativamente mayor con el nitrógeno químico, mientras que el contenido de materia seca fue menor. No se encontraron diferencias signifi cativas entre el tratamiento control y los tratamientos orgánicos.

  15. Construcción de celdas calorimétricas metálicas con escudos adiabáticos

    Directory of Open Access Journals (Sweden)

    Carlos A. Ruiz

    2010-07-01

    Full Text Available Se discuten los criterios de diseño y la caracterización térmica de ccldiis calorimétricas construidas en cobre dorado y aluminio, que son acopladas a un calorímetro de inmersión para el estudio de mojado de sólidos porosos. Los resultados muestran que las celdas metálicas presentan constantes fugas térmicas y tiempos de equilibrio menores que los hallados en las celdas de vidrios tradicionales tipo Dewar. Los mejores resultados se obtiene con la celda de aluminio provista de escudos adiabáticos flotantes, construidos en lámina del mismo material, con valores de constantes de fugas tcrinicas del orden de 3,5 * 10 ' min" ' y tiempos de equilibrio de solamente 8 minutos. La instalación calorimétrica completa se calibra secundariamente, con la determinación del calor de mezcla del sistema benccnociclohcxano; los resultados están en buen acuerdo con los registrados en la literatura.

  16. Mild Caloric Restriction Decreases Insulin Requirements in Patients With Type 2 Diabetes and Severe Insulin Resistance.

    Science.gov (United States)

    Meehan, Cristina Adelia; Cochran, Elaine; Mattingly, Megan; Gorden, Phillip; Brown, Rebecca J

    2015-07-01

    Type 2 diabetes (T2D) affects ~10% of the US population, a subset of whom have severe insulin resistance (SIR) (>200 units/d). Treatment of these patients with high-dose insulin presents logistical and compliance challenges. We hypothesized that mild caloric restriction would reduce insulin requirements in patients with T2D and SIR.This was a retrospective study at the National Institutes of Health Clinical Center. Inclusion criteria were as follows: T2D, and insulin dose >200 units/d or >2 units/kg/d. The intervention consisted of mild caloric restriction during a 3 to 6-day hospitalization. The major outcomes were change in insulin dose and blood glucose from admission to discharge.Ten patients met inclusion criteria. Baseline glycated hemoglobin A1c was 10.0 ± 1.6% and body mass index 38.8 ± 9.0 kg/m. Food intake was restricted from 2210 ± 371 kcal/d preadmission to 1810 ± 202 during the hospital stay (16.5% reduction). Insulin dose decreased from 486 ± 291 units/d preadmission to 223 ± 127 at discharge (44% reduction, P = 0.0025). Blood sugars decreased nonsignificantly in the fasting state (from 184 ± 85 to 141 ± 42, P = 0.20), before lunch (239 ± 68 to 180 ± 76, P = 0.057), and at bedtime (212 ± 95 to 176 ± 48, P = 0.19), and significantly decreased before dinner (222 ± 92 to 162 ± 70, P = 0.016).Mild caloric restriction, an accessible and affordable intervention, substantially reduced insulin doses in patients with T2D and SIR. Further studies are needed to determine if the intervention and results are sustainable outside of a hospital setting.

  17. New developments in the study of the caloric curve for finite nuclei within relativistic models

    International Nuclear Information System (INIS)

    Menezes, Debora Peres; Providencia, C.

    2001-01-01

    Relativistic nuclear models have been widely used in describing infinite nuclear matter and finite nuclei properties. With the help of the Thomas Fermi approximation, we have investigated droplet formation in the liquid-gas phase transition in cold and warm asymmetric nuclear matters using the non-linear Walecka model. We have shown that the optimal nuclear size of a droplet in a neutron gas is determined by a delicate balance between nuclear Coulomb and surface energies. On the other hand, the production of several intermediate mass fragments in a short time scale during heavy ion collisions is known as nuclear multifragmentation. In these experiments, the spectator matter has been used to investigate a possible liquid-gas phase transition. The caloric curve, which is given by the excitation energy per nucleon in terms of the thermodynamic temperature is an important quantity to be investigated in the search for a signal of a phase transition. In the present work we obtain the excitation energies of arising droplets in a vapor system, up to T = 6.5 MeV. The droplets are described in terms of a non-linear Walecka-type model with the NL1 parameterization, within the Thomas-Fermi approximation. We conclude that the excitation energies of droplets either corresponding to 150 Sm or 166 Sm, are consistent with the caloric curve in the Fermi gas approximation with a level density parameter A/13. This result agrees with experimental data obtained in heavy-ion collisions at intermediate energies. We have shown that the caloric curve is sensitive to the proton fraction and the inclusion of the Coulomb interaction is important. (author)

  18. Effect of solid-meal caloric content on gastric emptying kinetics of solids and liquids.

    Science.gov (United States)

    Urbain, J L; Siegel, J A; Mortelmans, L; van Cutsem, E; van den Maegdenbergh, V; de Roo, M

    1989-08-01

    In this study, we have evaluated the effect of the caloric content of a physiological test meal on the gastric emptying kinetics of solids and liquids. 22 healthy male volunteers were studied in two groups matched for age. After an overnight fast, each volunteer underwent the same test procedure; in the first group (G I), 10 volunteers received a meal consisting of bread, 111In-DTPA water and 1 scrambled egg labeled with 99mTc-labelled sulphur colloid; in the second group (G II) 12 volunteers were given the same meal but with 2 labeled eggs in order to increase the caloric content of the solid phase meal. Simultaneous anterior and posterior images were recorded using a dual-headed gamma camera. Solid and liquid geometric mean data were analyzed to determine the lag phase, the emptying rate and the half-emptying time for both solids and liquids. Solid and liquid gastric half-emptying times were significantly prolonged in G II compared to G I volunteers. For the solid phased, the delay was accounted for by a longer lag phase and a decrease in the equilibrium emptying rate. The emptying rate of the liquid phase was significantly decreased in G II compared to G I. Within each group, no statistically significant difference was observed between solid and liquid emptying rates. We conclude that the caloric content of the solid portion of a meal not only alters the emptying of the solid phase but also affects the emptying of the liquid component of the meal.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. Obesity, abdominal obesity, physical activity, and caloric intake in US adults: 1988 to 2010.

    Science.gov (United States)

    Ladabaum, Uri; Mannalithara, Ajitha; Myer, Parvathi A; Singh, Gurkirpal

    2014-08-01

    Obesity and abdominal obesity are associated independently with morbidity and mortality. Physical activity attenuates these risks. We examined trends in obesity, abdominal obesity, physical activity, and caloric intake in US adults from 1988 to 2010. Univariate and multivariate analyses were performed using National Health and Nutrition Examination Survey data. Average body mass index (BMI) increased by 0.37% (95% confidence interval [CI], 0.30-0.44) per year in both women and men. Average waist circumference increased by 0.37% (95% CI, 0.30-0.43) and 0.27% (95% CI, 0.22-0.32) per year in women and men, respectively. The prevalence of obesity and abdominal obesity increased substantially, as did the prevalence of abdominal obesity among overweight adults. Younger women experienced the greatest increases. The proportion of adults who reported no leisure-time physical activity increased from 19.1% (95% CI, 17.3-21.0) to 51.7% (95% CI, 48.9-54.5) in women, and from 11.4% (95% CI, 10.0-12.8) to 43.5% (95% CI, 40.7-46.3) in men. Average daily caloric intake did not change significantly. BMI and waist circumference trends were associated with physical activity level but not caloric intake. The associated changes in adjusted BMIs were 8.3% (95% CI, 6.9-9.6) higher among women and 1.7% (95% CI, 0.68-2.8) higher among men with no leisure-time physical activity compared with those with an ideal level of leisure-time physical activity. Our analyses highlight important dimensions of the public health problem of obesity, including trends in younger women and in abdominal obesity, and lend support to the emphasis placed on physical activity by the Institute of Medicine. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Obesity, Abdominal Obesity, Physical Activity, and Caloric Intake in U.S. Adults: 1988-2010

    Science.gov (United States)

    Ladabaum, Uri; Mannalithara, Ajitha; Myer, Parvathi A.; Singh, Gurkirpal

    2014-01-01

    Background Obesity and abdominal obesity are independently associated with morbidity and mortality. Physical activity attenuates these risks. We examined trends in obesity, abdominal obesity, physical activity, and caloric intake in U.S. adults from 1988 to 2010. Methods Univariate and multivariate analyses were performed using National Health and Nutrition Examination Survey (NHANES) data. Results Average body-mass index (BMI) increased by 0.37% (95% CI, 0.30-0.44%) per year in both women and men. Average waist circumference increased by 0.37% (95% CI, 0.30-0.43%) and 0.27% (95% CI, 0.22-0.32%) per year in women and men, respectively. The prevalence of obesity and abdominal obesity increased substantially, as did the prevalence of abdominal obesity among overweight adults. Younger women experienced the greatest increases. The proportion of adults who reported no leisure-time physical activity increased from 19.1% (95% CI, 17.3-21.0%) to 51.7% (95% CI, 48.9-54.5%) in women, and from 11.4% (95% CI, 10.0-12.8%) to 43.5% (95% CI, 40.7-46.3%) in men. Average daily caloric intake did not change significantly. BMI and waist circumference trends were associated with physical activity level, but not caloric intake. The associated changes in adjusted BMIs were 8.3% (95% CI, 6.9-9.6%) higher among women and 1.7% (95% CI, 0.68-2.8%) higher among men with no leisure-time physical activity compared to those with an ideal level of leisure-time physical activity. Conclusions Our analyses highlight important dimensions of the public health problem of obesity, including trends in younger women and in abdominal obesity, and lend support to the emphasis placed on physical activity by the Institute of Medicine. PMID:24631411

  2. Low-Fat Diet With Caloric Restriction Reduces White Matter Microglia Activation During Aging

    Directory of Open Access Journals (Sweden)

    Zhuoran Yin

    2018-03-01

    Full Text Available Rodent models of both aging and obesity are characterized by inflammation in specific brain regions, notably the corpus callosum, fornix, and hypothalamus. Microglia, the resident macrophages of the central nervous system, are important for brain development, neural support, and homeostasis. However, the effects of diet and lifestyle on microglia during aging are only partly understood. Here, we report alterations in microglia phenotype and functions in different brain regions of mice on a high-fat diet (HFD or low-fat diet (LFD during aging and in response to voluntary running wheel exercise. We compared the expression levels of genes involved in immune response, phagocytosis, and metabolism in the hypothalamus of 6-month-old HFD and LFD mice. We also compared the immune response of microglia from HFD or LFD mice to peripheral inflammation induced by intraperitoneal injection of lipopolysaccharide (LPS. Finally, we investigated the effect of diet, physical exercise, and caloric restriction (40% reduction compared to ad libitum intake on microglia in 24-month-old HFD and LFD mice. Changes in diet caused morphological changes in microglia, but did not change the microglia response to LPS-induced systemic inflammation. Expression of phagocytic markers (i.e., Mac-2/Lgals3, Dectin-1/Clec7a, and CD16/CD32 in the white matter microglia of 24-month-old brain was markedly decreased in calorically restricted LFD mice. In conclusion, LFD resulted in reduced activation of microglia, which might be an underlying mechanism for the protective role of caloric restriction during aging-associated decline.

  3. Low-Fat Diet With Caloric Restriction Reduces White Matter Microglia Activation During Aging.

    Science.gov (United States)

    Yin, Zhuoran; Raj, Divya D; Schaafsma, Wandert; van der Heijden, Roel A; Kooistra, Susanne M; Reijne, Aaffien C; Zhang, Xiaoming; Moser, Jill; Brouwer, Nieske; Heeringa, Peter; Yi, Chun-Xia; van Dijk, Gertjan; Laman, Jon D; Boddeke, Erik W G M; Eggen, Bart J L

    2018-01-01

    Rodent models of both aging and obesity are characterized by inflammation in specific brain regions, notably the corpus callosum, fornix, and hypothalamus. Microglia, the resident macrophages of the central nervous system, are important for brain development, neural support, and homeostasis. However, the effects of diet and lifestyle on microglia during aging are only partly understood. Here, we report alterations in microglia phenotype and functions in different brain regions of mice on a high-fat diet (HFD) or low-fat diet (LFD) during aging and in response to voluntary running wheel exercise. We compared the expression levels of genes involved in immune response, phagocytosis, and metabolism in the hypothalamus of 6-month-old HFD and LFD mice. We also compared the immune response of microglia from HFD or LFD mice to peripheral inflammation induced by intraperitoneal injection of lipopolysaccharide (LPS). Finally, we investigated the effect of diet, physical exercise, and caloric restriction (40% reduction compared to ad libitum intake) on microglia in 24-month-old HFD and LFD mice. Changes in diet caused morphological changes in microglia, but did not change the microglia response to LPS-induced systemic inflammation. Expression of phagocytic markers (i.e., Mac-2/Lgals3, Dectin-1/Clec7a, and CD16/CD32) in the white matter microglia of 24-month-old brain was markedly decreased in calorically restricted LFD mice. In conclusion, LFD resulted in reduced activation of microglia, which might be an underlying mechanism for the protective role of caloric restriction during aging-associated decline.

  4. Effect of solid-meal caloric content on gastric emptying kinetics of solids and liquids

    International Nuclear Information System (INIS)

    Urbain, J.L.; Mortelmans, L.; Cutsem, E. van; Maegdenbergh, V. van den; Roo, M. de

    1989-01-01

    In this study, we have evaluated the effect of the caloric content of a physiological test meal on the gastric emptying kinetics of solids and liquids. 22 healthy male volunteers were studied in two groups matched for age. After an overnight fast, each volunteer underwent the same test procedure; in the first group (G I), 10 volunteers received a meal consisting of bread, 111 In-DTPA water and 1 scrambled egg labeled with 99m Tc-labelled sulphur colloid; in the second group (G II) 12 volunteers were given the same meal but with 2 labeled eggs in order to increase the caloric content of the solid phase meal. Simultaneous anterior and posterior images were recorded using a dual-headed gamma camera. Solid and liquid geometric mean data were analyzed to determine the lag phase, the emptying rate and the half-emptying time for both solids and liquids. Solid and liquid gastric half-emptying times were significantly prolonged in G II compared to G I volunteers. For the solid phased, the delay was accounted for by a longer lag phase and a decrease in the equilibrium emptying rate. The emptying rate of the liquid phase was significantly decreased in G II compared to G I. Within each group, no statistically significant difference was observed between solid and liquid emptying rates. We conclude that the caloric content of the solid portion of a meal not only alters the emptying of the solid phase but also affects the emptying of the liquid component of the meal. (orig.) [de

  5. Caloric restriction in C57BL/6J mice mimics therapeutic fasting in humans

    Directory of Open Access Journals (Sweden)

    Denny Christine A

    2006-05-01

    Full Text Available Abstract Background Caloric restriction (CR has long been recognized as a dietary therapy that improves health and increases longevity. Little is known about the persistent effects of CR on plasma biomarkers (glucose, ketone bodies, and lipids following re-feeding in mice. It is also unclear how these biomarker changes in calorically restricted mice relate to those observed previously in calorically restricted humans. Results Three groups of individually housed adult female C57BL/6J (B6 mice (n = 4/group were fed a standard rodent chow diet either: (1 unrestricted (UR; (2 restricted for three weeks to reduce body weight by approximately 15–20% (R; or (3 restricted for three weeks and then re-fed unrestricted (ad libitum for an additional three weeks (R-RF. Body weight and food intake were measured throughout the study, while plasma lipids and levels of glucose and ketone bodies (β-hydroxybutyrate were measured at the termination of the study. Plasma glucose, phosphatidylcholine, cholesterol, and triglycerides were significantly lower in the R mice than in the UR mice. In contrast, plasma fatty acids and β-hydroxybutyrate were significantly higher in the R mice than in the UR mice. CR had no effect on plasma phosphatidylinositol levels. While body weight and plasma lipids of the R-RF mice returned to unrestricted levels upon re-feeding, food intake and glucose levels remained significantly lower than those prior to the initiation of CR. Conclusion CR establishes a new homeostatic state in B6 mice that persists for at least three weeks following ad libitum re-feeding. Moreover, the plasma biomarker changes observed in B6 mice during CR mimic those reported in humans on very low calorie diets or during therapeutic fasting.

  6. Lost in processing? Perceived healthfulness, taste and caloric content of whole and processed organic food.

    Science.gov (United States)

    Prada, Marília; Garrido, Margarida V; Rodrigues, David

    2017-07-01

    The "organic" claim explicitly informs consumers about the food production method. Yet, based on this claim, people often infer unrelated food attributes. The current research examined whether the perceived advantage of organic over conventional food generalizes across different organic food types. Compared to whole organic foods, processed organic foods are less available, familiar and prototypical of the organic food category. In two studies (combined N = 258) we investigated how both organic foods types were perceived in healthfulness, taste and caloric content when compared to their conventional alternatives. Participants evaluated images of both whole (e.g., lettuce) and processed organic food exemplars (e.g., pizza), and reported general evaluations of these food types. The association of these evaluations with individual difference variables - self-reported knowledge and consumption of organic food, and environmental concerns - was also examined. Results showed that organically produced whole foods were perceived as more healthful, tastier and less caloric than those produced conventionally, thus replicating the well-established halo effect of the organic claim in food evaluation. The organic advantage was more pronounced among individuals who reported being more knowledgeable about organic food, consumed it more frequently, and were more environmentally concerned. The advantage of the organic claim for processed foods was less clear. Overall, processed organic (vs. conventional) foods were perceived as tastier, more healthful (Study 1) or equally healthful (Study 2), but also as more caloric. We argue that the features of processed food may modulate the impact of the organic claim, and outline possible research directions to test this assumption. Uncovering the specific conditions in which food claims bias consumer's perceptions and behavior may have important implications for marketing, health and public-policy related fields. Copyright © 2017 Elsevier

  7. Targeting energy metabolism in brain cancer with calorically restricted ketogenic diets.

    Science.gov (United States)

    Seyfried, Thomas N; Kiebish, Michael; Mukherjee, Purna; Marsh, Jeremy

    2008-11-01

    Information is presented on the calorically restricted ketogenic diet (CRKD) as an alternative therapy for brain cancer. In contrast to normal neurons and glia, which evolved to metabolize ketone bodies as an alternative fuel to glucose under energy-restricted conditions, brain tumor cells are largely glycolytic due to mitochondrial defects and have a reduced ability to metabolize ketone bodies. The CRKD is effective in managing brain tumor growth in animal models and in patients, and appears to act through antiangiogenic, anti-inflammatory, and proapoptotic mechanisms.

  8. La demanda de las calorías en Venezuela 1970-1995:

    OpenAIRE

    Anido R., José Daniel; Gutiérrez S., Alejandro

    2003-01-01

    1.- Artículos Cartay, Rafael. "Los productos típicos y su reglamentación. Una tentativa de aplicación de la denominación de origen al cacao venezolano" Kalvatchev, Zlatko; Garzaro, Domingo; Guerra Cedezo, Franklin. "Theobroma Cacao L.: Un nuevo enfoque para nutrición y salud" Anido, Daniel; Gutiérrez, Alejandro. "La demanda de las calorías en Venezuela 1970-1995: Algunas evidencias empíricas" Molina, Luisa Elena. "Notas sobre la situación de la producción primaria de arroz en Ven...

  9. 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.

  10. Transferência de calor e massa de um condensador evaporativo em escala reduzida

    OpenAIRE

    Ivoni Carlos Acunha Júnior

    2010-01-01

    Este trabalho trata de um estudo experimental da transferência de calor e de massa de um condensador evaporativo, bem como, da relação existente entre as grandezas envolvidas durante a sua operação. Para o desenvolvimento da pesquisa foi construído um condensador evaporativo de pequeno porte com dimensões proporcionais a condensadores comercialmente fabricados no Brasil para operar com R-22 como fluido refrigerante. Este condensador tem 35 colunas e 12 fileiras de tubos de cobre de 6,35 mm de...

  11. On entropy change measurements around first order phase transitions in caloric materials.

    Science.gov (United States)

    Caron, Luana; Ba Doan, Nguyen; Ranno, Laurent

    2017-02-22

    In this work we discuss the measurement protocols for indirect determination of the isothermal entropy change associated with first order phase transitions in caloric materials. The magneto-structural phase transitions giving rise to giant magnetocaloric effects in Cu-doped MnAs and FeRh are used as case studies to exemplify how badly designed protocols may affect isothermal measurements and lead to incorrect entropy change estimations. Isothermal measurement protocols which allow correct assessment of the entropy change around first order phase transitions in both direct and inverse cases are presented.

  12. 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)

    1998-12-31

    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.

  13. 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.

  14. Emotional reaction evaluation provoked by the vestibular caloric test through physiological variables monitoring.

    Science.gov (United States)

    Barona-de-Guzmán, Rafael; Krstulovic-Roa, Claudio; Donderis-Malea, Elena; Barona-Lleó, Luz

    2018-03-08

    The emotional evaluation of the causes of vertigo is made using the clinical records and several subjective questionnaires. The aim of the present study is to evaluate the emotional response objectively, in normal subjects, during an induced vertigo crisis. A caloric vestibular test with cold water was performed on 30 healthy subjects. The following physiological parameters were monitored during the 60seconds prior to and the 60seconds after the stimulation: Skin Conductivity, Peripheral Pulse Volume, Body Temperature, Muscle Contraction, Heart Rate, and Respiratory Rate. The maximum angular speed of the nystagmus slow phase at each stimulation was assessed. Skin conductance presented a statistically significant increase during the vertigo crisis in relation to the prior period while the peripheral pulse volume presented a statistically significant decrease. There was no relationship between the slow phase of the provoked nystagmus angular speed and skin conductance and peripheral pulse volume changes. The decrease in peripheral pulse volume was significantly higher in the second vertigo crisis. Skin conductance and peripheral pulse volume changed significantly during a vertigo crisis. There was no relation between the provoked vertiginous crisis intensity and the changes produced in those variables. The stress generated by the caloric stimulation is higher in the second crisis, when the subject has experience of the vertigo caused by the stimulation. Copyright © 2018 Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. Publicado por Elsevier España, S.L.U. All rights reserved.

  15. The publics' understanding of daily caloric recommendations and their perceptions of calorie posting in chain restaurants

    Directory of Open Access Journals (Sweden)

    Bleich Sara N

    2010-03-01

    Full Text Available Abstract Background Calorie posting in chain restaurants has received increasing attention as a policy lever to reduce energy intake. Little research has assessed consumer understanding of overall daily energy requirements or perceived effectiveness of calorie posting. Methods A phone survey was conducted from May 1 through 17, 2009 with 663 randomly selected, nationally-representative adults aged 18 and older, including an oversample of Blacks and Hispanics in the United States. To examine differences in responses by race and ethnicity (White, Black, and Hispanic and gender, we compared responses by conducting chi-squared tests for differences in proportions. Results We found that most Americans were knowledgeable about energy requirements for moderately active men (78% and women (69%, but underestimated energy requirements for inactive adults (60%. Whites had significantly higher caloric literacy and confidence about their caloric knowledge than Blacks and Hispanics (p Conclusion Mandating calorie posting in chain restaurants may be a useful policy tool for promoting energy balance, particularly among Blacks, Hispanics and women who have higher obesity risk.

  16. Diet-beverage consumption and caloric intake among US adults, overall and by body weight.

    Science.gov (United States)

    Bleich, Sara N; Wolfson, Julia A; Vine, Seanna; Wang, Y Claire

    2014-03-01

    We examined national patterns in adult diet-beverage consumption and caloric intake by body-weight status. We analyzed 24-hour dietary recall with National Health and Nutrition Examination Survey 1999-2010 data (adults aged ≥ 20 years; n = 23 965). Overall, 11% of healthy-weight, 19% of overweight, and 22% of obese adults drink diet beverages. Total caloric intake was higher among adults consuming sugar-sweetened beverages (SSBs) compared with diet beverages (2351 kcal/day vs 2203 kcal/day; P = .005). However, the difference was only significant for healthy-weight adults (2302 kcal/day vs 2095 kcal/day; P < .001). Among overweight and obese adults, calories from solid-food consumption were higher among adults consuming diet beverages compared with SSBs (overweight: 1965 kcal/day vs 1874 kcal/day; P = .03; obese: 2058 kcal/day vs 1897 kcal/day; P < .001). The net increase in daily solid-food consumption associated with diet-beverage consumption was 88 kilocalories for overweight and 194 kilocalories for obese adults. Overweight and obese adults drink more diet beverages than healthy-weight adults and consume significantly more solid-food calories and a comparable total calories than overweight and obese adults who drink SSBs. Heavier US adults who drink diet beverages will need to reduce solid-food calorie consumption to lose weight.

  17. High caloric intake at breakfast vs. dinner differentially influences weight loss of overweight and obese women.

    Science.gov (United States)

    Jakubowicz, Daniela; Barnea, Maayan; Wainstein, Julio; Froy, Oren

    2013-12-01

    Few studies examined the association between time-of-day of nutrient intake and the metabolic syndrome. Our goal was to compare a weight loss diet with high caloric intake during breakfast to an isocaloric diet with high caloric intake at dinner. Overweight and obese women (BMI 32.4 ± 1.8 kg/m(2) ) with metabolic syndrome were randomized into two isocaloric (~1400 kcal) weight loss groups, a breakfast (BF) (700 kcal breakfast, 500 kcal lunch, 200 kcal dinner) or a dinner (D) group (200 kcal breakfast, 500 kcal lunch, 700 kcal dinner) for 12 weeks. The BF group showed greater weight loss and waist circumference reduction. Although fasting glucose, insulin, and ghrelin were reduced in both groups, fasting glucose, insulin, and HOMA-IR decreased significantly to a greater extent in the BF group. Mean triglyceride levels decreased by 33.6% in the BF group, but increased by 14.6% in the D group. Oral glucose tolerance test led to a greater decrease of glucose and insulin in the BF group. In response to meal challenges, the overall daily glucose, insulin, ghrelin, and mean hunger scores were significantly lower, whereas mean satiety scores were significantly higher in the BF group. High-calorie breakfast with reduced intake at dinner is beneficial and might be a useful alternative for the management of obesity and metabolic syndrome. Copyright © 2013 The Obesity Society.

  18. Oral nutritional supplementation increases caloric and protein intake in peritoneal dialysis patients.

    Science.gov (United States)

    Boudville, Neil; Rangan, Anna; Moody, Harry

    2003-03-01

    Malnutrition is highly prevalent in peritoneal dialysis (PD) patients and is associated with a poor prognosis. Attempts to improve nutritional status with enteral supplements have yielded poor results. We performed a crossover-design trial on 13 PD patients to investigate whether these patients reduce their food intake after drinking oral nutritional supplements. Patients attended three visits in which they were administered a standard oral nutritional supplement either 2 hours or 30 minutes before lunch or a placebo drink 30 minutes before lunch. Lunch was provided as a self-select buffet-style meal, and food intake was measured. Total intake was calculated by adding the nutritional content of the oral supplement. Patients showed poor food intake, with mean values equaling only 18% of the recommended daily intake for calories and 34% for protein. Drinking the supplement 2 hours before lunch resulted in a significant increase compared with the placebo visit in total caloric (430 to 843 kcal; P lunch. These results indicate that oral nutritional supplements administered before a meal may significantly increase caloric and protein intakes of PD patients. Copyright 2003 by the National Kidney Foundation, Inc.

  19. 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.

  20. The ageing phenome: caloric restriction and hormones promote neural cell survival, growth, and de-differentiation.

    Science.gov (United States)

    Timiras, Paola S; Yaghmaie, Farzin; Saeed, Omar; Thung, Elaine; Chinn, Garrett

    2005-01-01

    The phenome represents the observable properties of an organism that have developed under the continued influences of both genome and environmental factors. Phenotypic properties are expressed through the functions of cells, organs and body systems that operate optimally, close to equilibrium. In complex organisms, maintenance of the equilibrium is achieved by the interplay of several regulatory mechanisms. In the elderly, dynamic instability may lead to progressive loss of normal function, failure of adaptation and increased pathology. Extensive research (reported elsewhere in this journal) has demonstrated that genetic manipulations of endocrine signaling in flies, worms and mice increase longevity. Another effective strategy for prolonging the lifespan is caloric restriction: in data presented here, the persistence of estrogen-sensitive cells in the hypothalamus of caloric restricted 22-month-old female mice, may explain the persistence of reproductive function at an age, when reproductive function has long ceased in ad libitum fed controls. Still another strategy utilizes the effects of epidermal growth factor (EGF) to promote in vitro proliferation of neuroglia, astrocytes and oligodendrocytes. Their subsequent de-differentiation generates immature precursor cells potentially capable of differentiating into neuroblasts and neurons. These and other examples suggest that, in terms of functional outcomes, "the genome proposes but the phenome disposes".

  1. Caloric restriction in the presence of attractive food cues: external cues, eating, and weight.

    Science.gov (United States)

    Polivy, Janet; Herman, C Peter; Coelho, Jennifer S

    2008-08-06

    A growing body of research on caloric restriction (CR) in many species of laboratory animals suggests that underfeeding leads to better health and longevity in the calorically-restricted animal (e.g., see [[34]. J.P. Pinel, S. Assanand and D.R. Lehman, (2000). Hunger, eating and ill health. Am Psychol, 55, 1105-1116.], for a review). Although some objections have been raised by scientists concerned about negative psychological and behavioral sequelae of such restriction, advocates of CR continue to urge people to adopt sharply reduced eating regimes in order to increase their longevity. Yet very few people are even attempting to reap the benefits of such restriction. The present paper explores one factor that may deter many humans from drastically reducing their food consumption--the presence of abundant, attractive food cues in the environment. Research on the influence of food cues on food-related behaviors is reviewed to demonstrate that the presence of food cues makes restriction of intake more difficult.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    International Nuclear Information System (INIS)

    Marcelli, Vincenzo; Esposito, Fabrizio; Aragri, Adriana; Furia, Teresa; Riccardi, Pasquale; Tosetti, Michela; Biagi, Laura; Marciano, Elio; Di Salle, Francesco

    2009-01-01

    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.

  4. Effect of caloric restriction on gut permeability, inflammation markers, and fecal microbiota in obese women.

    Science.gov (United States)

    Ott, Beate; Skurk, Thomas; Hastreiter, Ljiljana; Lagkouvardos, Ilias; Fischer, Sandra; Büttner, Janine; Kellerer, Teresa; Clavel, Thomas; Rychlik, Michael; Haller, Dirk; Hauner, Hans

    2017-09-20

    Recent findings suggest an association between obesity, loss of gut barrier function and changes in microbiota profiles. Our primary objective was to examine the effect of caloric restriction and subsequent weight reduction on gut permeability in obese women. The impact on inflammatory markers and fecal microbiota was also investigated. The 4-week very-low calorie diet (VLCD, 800 kcal/day) induced a mean weight loss of 6.9 ± 1.9 kg accompanied by a reduction in HOMA-IR (Homeostasis model assessment-insulin resistance), fasting plasma glucose and insulin, plasma leptin, and leptin gene expression in subcutaneous adipose tissue. Plasma high-molecular weight adiponectin (HMW adiponectin) was significantly increased after VLCD. Plasma levels of high-sensitivity C-reactive protein (hsCRP) and lipopolysaccharide-binding protein (LBP) were significantly decreased after 28 days of VLCD. Using three different methods, gut paracellular permeability was decreased after VLCD. These changes in clinical parameters were not associated with major consistent changes in dominant bacterial communities in feces. In summary, a 4-week caloric restriction resulted in significant weight loss, improved gut barrier integrity and reduced systemic inflammation in obese women.

  5. Diseño y síntesis electrónica de la etapa de acondicionamiento analógico de un estetoscopio electrónico mediante circuitos programables FPAA

    OpenAIRE

    Gancedo Rodrigo, Jaime

    2015-01-01

    El objetivo principal de este Trabajo es el diseño, implementación y verificación de un sistema electrónico que permita acondicionar señales fonocardiográficas mediante circuitería analógica inmediatamente después de su adquisición con un estetoscopio electrónico. Para ello, se realizará un estudio de las características de las señales fonocardiográficas, se revisarán propuestas previas de sistemas con un propósito parecido y se propondrá una solución que satisfaga los requisitos definidos. U...

  6. 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

    Directory of Open Access Journals (Sweden)

    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.

  7. EFFECTS TO MODIFY THE CALORIC CONTENT OF WATER ON BODY WEIGHT, WATER, FOOD AND CALORIES CONSUMPTION IN RATS

    Directory of Open Access Journals (Sweden)

    ALMA GABRIELA MARTÍNEZ

    2006-05-01

    Full Text Available Six albino rats were divided in two experimental groups and one control. The experiment began withfifteen days of free access; subsequently experimental groups maintained available three concentrationsof glucose: high, middle and low. First group received high-middle-low-high-middle-low sequence andsecond group received low-middle-high-low-middle-high sequence during six days. Control group notreceived glucose concentrations. Caloric concentration of food never changed. Results suggest thatmodification of caloric concentration in water affects feeding behavior. Nevertheless, water with glucoseconsumption did not change body weight.

  8. FORMACIÓN DE GRÁNULOS ANAEROBIOS SIN LODOS INOCULADOS EN UN REACTOR DE BIOPELÍCULA ANAEROBIA TIPO INTERCAMBIADOR DE CALOR (RBAIC

    Directory of Open Access Journals (Sweden)

    Ramiro Escalera Vásquez

    2012-07-01

    Full Text Available Se ha estudiado experimentalmente el fenómeno de la formación de gránulos anaerobios en la puesta en marcha de un Reactor de Biopelícula Anaerobia Tipo Intercambiador de Calor (RBAIC, utilizado en el tratamiento de aguas residuales provenientes de una planta de procesamiento de melazas de baja concentración, 0,45 g-C L-1. El reactor fue operado en modo de flujo ascendente de un solo paso a bajas temperaturas promedio del líquido (15° C a 25° C y tiempos de retención hidráulica (TRH de 16 h y 6,1 h. La granulación puede proceder sin la inoculación de grandes cantidades iniciales de lodo biológico anaerobio. La granulación es posible aún con concentraciones iniciales muy pequeñas de microorganismos, siempre y cuando los mismos estén bien aclimatados al tipo de agua residual y las condiciones ambientales. Es posible tratar tasas de carga orgánica volumétrica entre 1,8 y 3,3 g-DQO L-1 d-1 a temperaturas promedio menores a 25° C con concentraciones de biomasa tan pequeñas como 2 g-SSV L-1. En un RBAIC, se pueden formar gránulos de 0,5 – 2 mm de diámetro en tres meses a temperaturas promedio menores a 25° C.

  9. One-Year Behavioral Treatment of Obesity: Comparison of Moderate and Severe Caloric Restriction and the Effects of Weight Maintenance Therapy.

    Science.gov (United States)

    Wadden, Thomas A.; And Others

    1994-01-01

    Compared weight losses of 49 obese women assigned to 52-week behavioral program combined with moderate or severe caloric restriction. Those in severe caloric restriction group lost significantly more weight during first 26 weeks but regained some weight. Reports of binge eating declined in both groups, and no relationship was observed between…

  10. 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…

  11. competencia con China

    Directory of Open Access Journals (Sweden)

    Elena de la Paz Hernández Águila

    2007-01-01

    Full Text Available El artículo ofrece un diagnóstico del desempeño de la industria mexicana del calzado desde la década de los ochenta hasta la actualidad. Analiza la problemática que ha enfrentado esta rama industrial a partir del proceso de apertura comercial y de la competencia en su mercado interno con productos provenientes de países asiáticos, particularmente China. Problematiza al respecto los retos y las perspectivas que a mediano plazo enfrentará este sector empresarial y sobre las posibilidades de competir en el mercado globalizado.

  12. Construir con Madera

    OpenAIRE

    Olabe-Velasco, F. (Fermín); Val-Hernández, Y. (Yolanda); Varela-de-la-Cruz, P. (Perla); Cabrero-Ballarín, J.M. (José Manuel)

    2010-01-01

    Guía divulgativa ‘Construir con madera’, elaborada por la Cátedra Madera de la Universidad de Navarra y el Gobierno de Navarra. La publicación pretende explicar de forma sencilla los beneficios y posibilidades de este material en la construcción, tanto en lo que respecta a su resistencia, comportamiento frente al fuego, durabilidad, capacidad de aislamiento, propiedades acústicas, estética, respeto al medio ambiente y sostenibilidad como fuente de energía. A modo de ejemplo, en la ...

  13. Entrevista con Giovanni Levi

    Directory of Open Access Journals (Sweden)

    Monica Oliveira

    2017-06-01

    Full Text Available En esta entrevista, Giovanni Levi - como un conocedor del tema de Familia - realiza una importante evaluación sobre el actual estado de las investigaciones realizadas en el Brasil y em el exterior. Con estilo franco, agudo y lucido critica las visiones tradicionales y sus ilusiones ypropone nuevos conceptos y métodos. La historia de la familia debería ceder espacio para el estudio de las redes relacionales o de los mundos relacionales. De la misma forma, la historia cuantitativa debería abrir espacio para el estudio de las cualidades. Ya con relación a la historia de las elites, tan estudiada y reproducida en una diversidad de trabajos, que deberíase mirar en otra perspectiva. Es decir, no mirar a las reglas sociales predeterminadas, sino a los desvíos y a las variaciones. Levi defiende que los historiadores deben trascender a los documentos que se encuentran fácilmente y que pueden fortalecer perspectivas deformadas y esequilibradas de la sociedad. Para él, los historiadores deben esforzarse por estudiar a aquellos grupos que dejaron pocos rastros documentales. En ese esfuerzo existiría una nueva mirada sobre la historia de la familia.

  14. 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

  15. Curcumin and piperine supplementation of obese mice under caloric restriction modulates body fat and interleukin-1beta

    Science.gov (United States)

    Background: Dietary bioactive compounds capable of improving metabolic profiles would be of great value, especially for overweight individuals undergoing a caloric restriction (CR) regimen. Curcumin (Cur), a possible anti-obesity compound, and piperine (Pip), a plausible enhancer of Cur's bioavailab...

  16. Metabolic alterations due to caloric restriction and every other day feeding in normal and growth hormone receptor knockout mice.

    Science.gov (United States)

    Westbrook, Reyhan; Bonkowski, Michael S; Arum, Oge; Strader, April D; Bartke, Andrzej

    2014-01-01

    Mutations causing decreased somatotrophic signaling are known to increase insulin sensitivity and extend life span in mammals. Caloric restriction and every other day (EOD) dietary regimens are associated with similar improvements to insulin signaling and longevity in normal mice; however, these interventions fail to increase insulin sensitivity or life span in growth hormone receptor knockout (GHRKO) mice. To investigate the interactions of the GHRKO mutation with caloric restriction and EOD dietary interventions, we measured changes in the metabolic parameters oxygen consumption (VO2) and respiratory quotient produced by either long-term caloric restriction or EOD in male GHRKO and normal mice. GHRKO mice had increased VO2, which was unaltered by diet. In normal mice, EOD diet caused a significant reduction in VO2 compared with ad libitum (AL) mice during fed and fasted conditions. In normal mice, caloric restriction increased both the range of VO2 and the difference in minimum VO2 between fed and fasted states, whereas EOD diet caused a relatively static VO2 pattern under fed and fasted states. No diet significantly altered the range of VO2 of GHRKO mice under fed conditions. This provides further evidence that longevity-conferring diets cause major metabolic changes in normal mice, but not in GHRKO mice.

  17. 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...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    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.

  20. 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

  1. Acute and short-term effects of caloric restriction on metabolic profile and brain activation in obese, postmenopausal women

    NARCIS (Netherlands)

    Jakobsdottir, S.; van Nieuwpoort, I. C.; van Bunderen, C. C.; de Ruiter, M. B.; Twisk, J. W. R.; Deijen, J. B.; Veltman, D. J.; Drent, M. L.

    2016-01-01

    Early anthropometric and metabolic changes during a caloric-restricted diet in obese postmenopausal women and correlations between these factors with activity in brain areas involved in processing of visual food related stimuli were investigated. An 8-week prospective intervention study of 18

  2. Acute and short term effects of caloric restriction on metabolic profile and brain activation in obese, postmenopausal women.

    NARCIS (Netherlands)

    Jakobsdottir, S.; van Nieuwpoort, I.C.; van Bunderen, C.C.; de Ruiter, M.B.; Twisk, J.W.R.; Deijen, J.B.; Veltman, D.J.; Drent, M.L.

    2016-01-01

    OBJECTIVE:Early anthropometric and metabolic changes during a caloric-restricted diet in obese postmenopausal women and correlations between these factors with activity in brain areas involved in processing of visual food related stimuli were investigated.SUBJECTS AND METHODS:An 8-week prospective

  3. Weight loss in obese men by caloric restriction and high-dose diazoxide-mediated insulin suppression.

    NARCIS (Netherlands)

    Boekel, G.A.J van; Loves, S.; Sorge, A.A. van; Ruinemans-Koerts, J.; Rijnders, T.; Boer, H. de

    2008-01-01

    OBJECTIVE: To examine the concept whether high-dose diazoxide (DZX)-mediated insulin suppression, in combination with moderate caloric restriction and increased physical activity, can establish a weight loss of at least 15% in obese hyperinsulinaemic men. DESIGN: Open, uncontrolled, 6-month pilot

  4. Influence of gender, parity, and caloric load on gastrorectal response in healthy subjects: a barostat study.

    Science.gov (United States)

    Sloots, Cornelius E J; Felt-Bersma, Richelle J F; Meuwissen, Stephan G M; Kuipers, Ernst J

    2003-03-01

    The gastrocolonic response consists of a prompt increase in colonic tone after a meal. With a barostat and a high compliant air-filled bag, it is possible to measure rectal tone by recording changes in volume at a constant intrabag pressure. The aim of this study was to evaluate the gastrorectal response in males and females as well as the effect of different caloric loads on the gastrorectal response. In 33 volunteers a barostat procedure during basal conditions and after a 600-kcal meal was performed. In 26 volunteers the procedure was repeated with a 1000-kcal meal. A meal response was defined as a decrease in volume of more than 10%. Phasic volume events (PVE) were defined as a 10% decrease in volume of 15-60 sec duration. After a 600-kcal meal, the decrease in volume after 1 hr was 28 +/- 7% (mean +/- SEM, P parity should be made when results are compared.

  5. Left caloric vestibular stimulation as a tool to reveal implicit and explicit parameters of body representation.

    Science.gov (United States)

    Sedda, A; Tonin, D; Salvato, G; Gandola, M; Bottini, G

    2016-04-01

    Homeostatic parameters, such as temperature, are related to body representation. In this study, we measured whether caloric vestibular stimulation (CVS) alters body temperature and tactile processing, and if in the direction predicted by a holistic body matrix representation. Skin temperature and tactile two-point discrimination (TPD) acuity were measured for both arms before, immediately after and with a delay from CVS. Participants were also administered a personality questionnaire and an anxiety inventory to rule out confounding factors. Two control experiments were planned to exclude casual variations. Our results show that temperature drops significantly in both arms after CVS. CVS also induces a bilateral improvement in tactile acuity (even though not immediately after but in the delayed condition). Finally, these effects are not due to learning, as demonstrated by the control experiment. In summary, our results suggest that vestibular stimulation updates body representation, supporting the evidence in favor of a body matrix. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Physical-chemical, caloric and sensory characterization of light jambolan (Syzygium cumini Lamarck jelly

    Directory of Open Access Journals (Sweden)

    Ellen Silva Lago-Vanzela

    2011-09-01

    Full Text Available In Brazil, several little economically explored fruits have good potential as raw material for the agro-industry. This study aimed to produce and determine the physical-chemical and sensory characteristics of light jambolan jelly. This fruit has intense purple color, which gave the jellies - both standard and light - a quite attractive visual aspect. The light jellies exhibited similar physical-chemical characteristics to the ones developed through the conventional method and; with the proportion of sweeteners used, the caloric values of the formulations were reduced to the range of 41 to 53%, attending the requirements of the Brazilian legislation for this type of product. The sensory profile obtained for the 4 light formulations developed, clearly showed the tasters' preference for the jelly elaborated with the association of cyclamate and saccharin. Thus, the results revealed good perspectives for the application of this fruit in the food industry.

  7. Caloric restriction suppresses apoptotic cell death in the mammalian cochlea and leads to prevention of presbycusis.

    Science.gov (United States)

    Someya, Shinichi; Yamasoba, Tatsuya; Weindruch, Richard; Prolla, Tomas A; Tanokura, Masaru

    2007-10-01

    Presbycusis is characterized by an age-related progressive decline of auditory function, and arises mainly from the degeneration of hair cells or spiral ganglion (SG) cells in the cochlea. Here we show that caloric restriction suppresses apoptotic cell death in the mouse cochlea and prevents late onset of presbycusis. Calorie restricted (CR) mice, which maintained body weight at the same level as that of young control (YC) mice, retained normal hearing and showed no cochlear degeneration. CR mice also showed a significant reduction in the number of TUNEL-positive cells and cleaved caspase-3-positive cells relative to middle-age control (MC) mice. Microarray analysis revealed that CR down-regulated the expression of 24 apoptotic genes, including Bak and Bim. Taken together, our findings suggest that loss of critical cells through apoptosis is an important mechanism of presbycusis in mammals, and that CR can retard this process by suppressing apoptosis in the inner ear tissue.

  8. Physiological-metabolic variables of caloric stress in cows under silvopastoral and prairie without trees

    International Nuclear Information System (INIS)

    Barragan Hernandez, Wilson Andres; Cajas-Giron, Yasmin Socorro; Mahecha-Ledesma, Lilliana

    2015-01-01

    Changes in physiological and metabolic parameters were assessed as indicators of caloric stress of cows under grazing were investigated. The study was developed at the Centro de Investigacion Corpoica Turipana, Region Caribe, Cerete, Colombia, during the years 2011-2012. Temperature (T) and relative humidity (H), and in animals: rectal temperature (RT), skin temperature (TP), respiratory rate (RF) and acid-base status were determined. The variables were measured in the morning (6:00 h) and in the afternoon (13:00 h). Effect of treatment on environmental temperature was found with 7 and 6% less temperature in p-Arbur-Arbor and p-Arbor, respectively, compared with the grass treatment. There was an effect of time (p [es

  9. Modulation infrared thermometry of caloric effects at up to kHz frequencies

    Science.gov (United States)

    Döntgen, Jago; Rudolph, Jörg; Waske, Anja; Hägele, Daniel

    2018-03-01

    We present a novel non-contact method for the direct measurement of caloric effects in low volume samples. The adiabatic temperature change ΔT of a magnetocaloric sample is very sensitively determined from thermal radiation. Rapid modulation of ΔT is induced by an oscillating external magnetic field. Detection of thermal radiation with a mercury-cadmium-telluride detector allows for measurements at field frequencies exceeding 1 kHz. In contrast to thermoacoustic methods, our method can be employed in vacuum which enhances adiabatic conditions especially in the case of small volume samples. Systematic measurements of the magnetocaloric effect as a function of temperature, magnetic field amplitude, and modulation frequency give a detailed picture of the thermal behavior of the sample. Highly sensitive measurements of the magnetocaloric effect are demonstrated on a 2 mm thick sample of gadolinium and a 60 μm thick Fe80B12Nb8 ribbon.

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

    Directory of Open Access Journals (Sweden)

    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.

  11. Cognitive Performances Are Selectively Enhanced during Chronic Caloric Restriction or Resveratrol Supplementation in a Primate

    Science.gov (United States)

    Marchal, Julia; Picq, Jean-Luc; Aujard, Fabienne

    2011-01-01

    Effects of an 18-month treatment with a moderate, chronic caloric restriction (CR) or an oral supplementation with resveratrol (RSV), a potential CR mimetic, on cognitive and motor performances were studied in non-human primates, grey mouse lemurs (Microcebus murinus). Thirty-three adult male mouse lemurs were assigned to three different groups: a control (CTL) group fed ad libitum, a CR group fed 70% of the CTL caloric intake, and an RSV group (RSV supplementation of 200 mg.kg−1.day−1) fed ad libitum. Three different cognitive tests, two motor tests, one emotional test and an analysis of cortisol level were performed in each group. Compared to CTL animals, CR or RSV animals did not show any change in motor performances evaluated by rotarod and jump tests, but an increase in spontaneous locomotor activity was observed in both groups. Working memory was improved by both treatments in the spontaneous alternation task. Despite a trend for CR group, only RSV supplementation increased spatial memory performances in the circular platform task. Finally, none of these treatments induced additional stress to the animals as reflected by similar results in the open field test and cortisol analyses compared to CTL animals. The present data provided the earliest evidence for a beneficial effect of CR or RSV supplementation on specific cognitive functions in a primate. Taken together, these results suggest that RSV could be a good candidate to mimic long-term CR effects and support the growing evidences that nutritional interventions can have beneficial effects on brain functions even in adults. PMID:21304942

  12. Coordinated multitissue transcriptional and plasma metabonomic profiles following acute caloric restriction in mice.

    Science.gov (United States)

    Selman, Colin; Kerrison, Nicola D; Cooray, Anisha; Piper, Matthew D W; Lingard, Steven J; Barton, Richard H; Schuster, Eugene F; Blanc, Eric; Gems, David; Nicholson, Jeremy K; Thornton, Janet M; Partridge, Linda; Withers, Dominic J

    2006-11-27

    Caloric restriction (CR) increases healthy life span in a range of organisms. The underlying mechanisms are not understood but appear to include changes in gene expression, protein function, and metabolism. Recent studies demonstrate that acute CR alters mortality rates within days in flies. Multitissue transcriptional changes and concomitant metabolic responses to acute CR have not been described. We generated whole genome RNA transcript profiles in liver, skeletal muscle, colon, and hypothalamus and simultaneously measured plasma metabolites using proton nuclear magnetic resonance in mice subjected to acute CR. Liver and muscle showed increased gene expressions associated with fatty acid metabolism and a reduction in those involved in hepatic lipid biosynthesis. Glucogenic amino acids increased in plasma, and gene expression for hepatic gluconeogenesis was enhanced. Increased expression of genes for hormone-mediated signaling and decreased expression of genes involved in protein binding and development occurred in hypothalamus. Cell proliferation genes were decreased and cellular transport genes increased in colon. Acute CR captured many, but not all, hepatic transcriptional changes of long-term CR. Our findings demonstrate a clear transcriptional response across multiple tissues during acute CR, with congruent plasma metabolite changes. Liver and muscle switched gene expression away from energetically expensive biosynthetic processes toward energy conservation and utilization processes, including fatty acid metabolism and gluconeogenesis. Both muscle and colon switched gene expression away from cellular proliferation. Mice undergoing acute CR rapidly adopt many transcriptional and metabolic changes of long-term CR, suggesting that the beneficial effects of CR may require only a short-term reduction in caloric intake.

  13. Caloric beverages consumed freely at meal-time add calories to an ad libitum meal.

    Science.gov (United States)

    Panahi, Shirin; El Khoury, Dalia; Luhovyy, Bohdan L; Goff, H Douglas; Anderson, G Harvey

    2013-06-01

    The objective was to compare the effects of ad libitum consumption of commonly consumed meal-time beverages on energy and fluid intakes and post-meal average subjective appetite and blood glucose in healthy adults. In a randomized controlled design, 29 males and females consumed to satiation an ad libitum pizza meal with one of five beverages in unlimited amount including water (0 kcal), 1% milk (44 kcal/100 ml), regular cola (44 kcal/100 ml), orange juice (44 kcal/100 ml) and diet cola (0 kcal). Food and fluid intakes were measured at the meal. Average subjective appetite and blood glucose were measured before and for 2h after the meal. Although energy intake from pizza was similar among all beverage treatments, the amount of fluid consumed (g) varied among the beverages with intake of orange juice higher than regular and diet cola, but not different from water or milk. Meal-time ingestion of caloric beverages, milk, orange juice and regular cola, led to higher total meal-time energy intakes compared to either water or diet cola. Post-meal blood glucose area under the curve (AUC) was lower after milk than after meals with water, orange juice and regular cola and post-meal average subjective appetite AUC was lower after milk than after meals with water. Meal intakes of nutrients including protein, calcium, phosphorus, zinc, vitamins B12, A and D were higher at the meal with milk compared to the other beverages. Thus, caloric beverages consumed ad libitum during a meal add to total meal-time energy intake, but 1% milk favors a lower post-meal blood glucose and average subjective appetite score and adds to nutrient intake. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Antagonistic targeting of the histamine H3 receptor decreases caloric intake in higher mammalian species.

    Science.gov (United States)

    Malmlöf, Kjell; Hastrup, Sven; Wulff, Birgitte Schellerup; Hansen, Barbara C; Peschke, Bernd; Jeppesen, Claus Bekker; Hohlweg, Rolf; Rimvall, Karin

    2007-04-15

    The main purpose of this study was to examine the effects of a selective histamine H(3) receptor antagonist, NNC 38-1202, on caloric intake in pigs and in rhesus monkeys. The compound was given intragastrically (5 or 15 mg/kg), to normal pigs (n=7) and subcutaneously (1 or 0.1mg/kg) to obese rhesus monkeys (n=9). The energy intake recorded following administration of vehicle to the same animals served as control for the effect of the compound. In addition, rhesus monkey and pig histamine H(3) receptors were cloned from hypothalamic tissues and expressed in mammalian cell lines. The in vitro antagonist potencies of NNC 38-1202 at the H(3) receptors were determined using a functional GTPgammaS binding assay. Porcine and human H(3) receptors were found to have 93.3% identity at the amino acid level and the close homology between the monkey and human H(3) receptors (98.4% identity) was confirmed. The antagonist potencies of NNC 38-1202 at the porcine, monkey and human histamine H(3) receptors were high as evidenced by K(i)-values being clearly below 20 nM, whereas the K(i)-value on the rat H(3) receptor was significantly higher (56+/-6.0 nM). NNC 38-1202, given to pigs in a dose of 15 mg/kg, produced a significant (p<0.05) reduction (55%) of calorie intake compared with vehicle alone, (132.6+/-10.0 kcal/kgday versus 59.7+/-10.2 kcal/kgday). In rhesus monkeys administration of 0.1 and 1mg/kg decreased (p<0.05) average calorie intakes by 40 and 75%, respectively. In conclusion, the present study demonstrates that antagonistic targeting of the histamine H(3) receptor decreases caloric intake in higher mammalian species.

  15. [Caloric value and energy allocation of Chloris virgata in northeast grassland].

    Science.gov (United States)

    Guo, J; Wang, R; Wang, W

    2001-06-01

    The rules of seasonal changes in caloric values of individual plant, stem, and leaves of Chloris virgata were similar, which had two peak values from early July to early August, and then decreased gradually. Those of inflorescence assumed U shape, and had two peak values in early August and middle September, respectively. The seasonal changes in caloric values of dead standing were irregular, and the maximum value was appeared in early August. The seasonal changes in existent energy value of the aboveground parts in Chloris virgata population presented double peak curve. The two peak values were appeared in early August and early September respectively, and the maximum value was 7381.27 kJ.m-2 in early September. The energy allocation in different seasons was leaf > stem in early July, stem > leaf > dead standing in middle July, stem > leaf > inflorescence > dead standing in August, stem > inflorescence > leaf > dead standing in early September, and stem > inflorescence > dead standing > leaf in middle September. The vertical structure of energy in the aboveground parts was that the energy value gradually increased from the earth's surface to 20 cm high, and then decreased. The maximum value, which accounted for 25.75% of energy in the aboveground parts, was appeared in the layer of 10-20 cm high. In the underground parts, the energy value progressively decreased with the increase of depth, and the maximum value, which accounted for 74.21% of energy in the underground parts, was appeared in the layer of 0-10 cm depth.

  16. Effects of caloric restriction and overnight fasting on cycling endurance performance.

    Science.gov (United States)

    Ferguson, Lisa M; Rossi, Kelly A; Ward, Emily; Jadwin, Emily; Miller, Todd A; Miller, Wayne C

    2009-03-01

    In addition to aerobic endurance and anaerobic capacity, high power-to-weight ratio (PWR) is important for cycling performance. Cyclists often try to lose weight before race season to improve body composition and optimize PWR. Research has demonstrated body fat-reducing benefits of exercise after fasting overnight. We hypothesized that fasted-state exercise in calorie-restricted trained cyclists would not result in performance decrements and that their PWR would improve significantly. We also hypothesized that substrate use during fasted-state submaximal endurance cycling would shift to greater reliance on fat. Ten trained, competitive cyclists completed a protocol consisting of baseline testing, 3 weeks of caloric restriction (CR), and post-CR testing. The testing sessions measured pre- and post-CR values for resting metabolic rate (RMR), body composition, VO2, PWR and power-to-lean weight ratio (PLWR), and power output, as well as 2-hour submaximal cycling performance, rating of perceived exertion (RPE), and respiratory exchange ratio (RER). There were no significant differences between baseline and post-CR for submaximal trial RER, power output, VO2, RMR, VO2max, or workload at VO2max. However, RPE was significantly lower, and PWR was significantly higher post-CR, whereas RER did not change. The cyclists' PWR and body composition improved significantly, and their overall weight, fat weight, and body fat percentage decreased. Lean mass was maintained. The cyclists' RPE decreased significantly during 2 hours of submaximal cycling post-CR, and there was no decrement in submaximal or maximal cycling performance after 3 weeks of CR combined with overnight fasting. Caloric restriction (up to 40% for 3 weeks) and exercising after fasting overnight can improve a cyclist's PWR without compromising endurance cycling performance.

  17. Effect of herbal medicine daikenchuto on oral and enteral caloric intake after liver transplantation: A multicenter, randomized controlled trial.

    Science.gov (United States)

    Kaido, Toshimi; Shinoda, Masahiro; Inomata, Yukihiro; Yagi, Takahito; Akamatsu, Nobuhisa; Takada, Yasutsugu; Ohdan, Hideki; Shimamura, Tsuyoshi; Ogura, Yasuhiro; Eguchi, Susumu; Eguchi, Hidetoshi; Ogata, Satoshi; Yoshizumi, Tomoharu; Ikegami, Toshihiko; Yamamoto, Michio; Morita, Satoshi; Uemoto, Shinji

    2018-03-20

    Postoperative early oral or enteral intake is a crucial element of the Enhanced Recovery After Surgery (ERAS) protocol. However, normal food intake or enteral feeding cannot be started early in the presence of coexisting bowel dysfunction in patients undergoing liver transplantation (LT). The aim of this multicenter, randomized, double-blinded, placebo-controlled trial was to determine the enhancement effects of the Japanese herbal medicine Daikenchuto (DKT) on oral/enteral caloric intake in patients undergoing LT. A total of 112 adult patients undergoing LT at 14 Japanese centers were enrolled. The patients were randomly assigned to receive either DKT or placebo from postoperative day (POD) 1 to 14. The primary endpoints were total oral/enteral caloric intake, abdominal distension, and pain on POD 7. The secondary endpoints included sequential changes in total oral/enteral caloric intake after LT, and portal venous flow volume and velocity in the graft. A total of 104 patients (DKT, n = 55; placebo, n = 49) were included in the analyses. There were no significant differences between the two groups in terms of primary endpoints. However, postoperative total oral/enteral caloric intake was significantly accelerated in the DKT group compared with the placebo group (P = 0.023). Moreover, portal venous flow volume (POD 10, 14) and velocity (POD 14) were significantly higher in the DKT group than in the placebo group (P = 0.047, P = 0.025, P = 0.014, respectively). Postoperative administration of DKT may enhance total oral/enteral caloric intake and portal venous flow volume and velocity after LT and favorably contribute to the performance of the ERAS protocol. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Acute and short-term effects of caloric restriction on metabolic profile and brain activation in obese, postmenopausal women.

    Science.gov (United States)

    Jakobsdottir, S; van Nieuwpoort, I C; van Bunderen, C C; de Ruiter, M B; Twisk, J W R; Deijen, J B; Veltman, D J; Drent, M L

    2016-11-01

    Early anthropometric and metabolic changes during a caloric-restricted diet in obese postmenopausal women and correlations between these factors with activity in brain areas involved in processing of visual food related stimuli were investigated. An 8-week prospective intervention study of 18 healthy postmenopausal women, with a body mass index of 30-35 kg m -2 . The first 2 weeks subjects were on an isocaloric diet and 4 weeks on a 1000 kcal restricted diet followed by 2 weeks on an isocaloric diet. Anthropometric and laboratory analyses were performed weekly during the isocaloric diet and three times a week during the caloric-restricted diet. Functional magnetic resonance imaging scans were obtained before and after the caloric restriction in four separate sessions (fasting or sated). Generalized Estimating Equations analysis was used for data analysis. A mean weight loss of 4.2±0.5 kg (4.8%) and a 4.2±0.4 cm decline in waist circumference were achieved. In the first week of caloric restriction, triglyceride, leptin, resistin and adiponectin levels as well as systolic blood pressure decreased and insulin-like growth factor-binding protein 1 levels increased. During and after weight loss, a significant increase in ghrelin levels was observed. Before weight loss, increased activation of the right amygdala was seen in response to food stimuli, and free fatty acids and glucose correlated with activity in various areas involved in food reward processing. After weight loss, fasting ghrelin and sated leptin levels correlated with activity in these areas. Already in the first week of caloric restriction in obese postmenopausal women, various favourable metabolic changes occur before clinically relevant weight loss is achieved. Activity in the amygdala region and correlations of metabolic factors with activity in brain areas involved in food reward processing differ substantially before and after weight loss.

  19. The impact of exercise training compared to caloric restriction on hepatic and peripheral insulin resistance in obesity.

    Science.gov (United States)

    Coker, Robert H; Williams, Rick H; Yeo, Sophie E; Kortebein, Patrick M; Bodenner, Don L; Kern, Philip A; Evans, William J

    2009-11-01

    It has been difficult to distinguish the independent effects of caloric restriction versus exercise training on insulin resistance. Utilizing metabolic feeding and supervised exercise training, we examined the influence of caloric restriction vs. exercise training with and without weight loss on hepatic and peripheral insulin resistance. Thirty-four obese, older subjects were randomized to: caloric restriction with weight loss (CR), exercise training with weight loss (EWL), exercise training without weight loss (EX), or controls. Based on an equivalent caloric deficit in EWL and CR, we induced matched weight loss. Subjects in the EX group received caloric compensation. Combined with [6,6(2)H(2)]glucose, an octreotide, glucagon, multistage insulin infusion was performed to determine suppression of glucose production (SGP) and insulin-stimulated glucose disposal (ISGD). Computed tomography scans were performed to assess changes in fat distribution. Body weight decreased similarly in EWL and CR, and did not change in EX and controls. The reduction in visceral fat was significantly greater in EWL (-71 +/- 15 cm(2)) compared to CR and EX. The increase in SGP was also almost 3-fold greater (27 +/- 2%) in EWL. EWL and CR promoted similar improvements in ISGD [+2.5 +/- 0.4 and 2.4 +/- 0.9 mg x kg fat-free mass (FFM)(-1) x min(-1)], respectively. EWL promoted the most significant reduction in visceral fat and the greatest improvement in SGP. Equivalent increases in ISGD were noted in EWL and CR, whereas EX provided a modest improvement. Based on our results, EWL promoted the optimal intervention-based changes in body fat distribution and systemic insulin resistance.

  20. 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.

  1. 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.

  2. autorregulado con estudiantes universitarios

    Directory of Open Access Journals (Sweden)

    Jairo Andrés Montes

    2005-01-01

    Full Text Available El propósito del presente estudio es describir la forma en la que se presentan los procesos de aprendizaje autorregulado con un grupo de estudiantes (22 estudiantes de tercer semestre de Psicología de la PUJ, Cali, en el evento de preparación para la presentación un examen. Asimismo se describen las correlaciones que ocurren entre las distintas fases de dicho proceso de autorregulación del aprendizaje. Para conseguir los objetivos propuestos se ha hecho uso de una observación de desempeño en tiempo real, es decir, de la observación durante una sesión de preparación de examen de los estudiantes, en la cual se emplearon protocolos verbales para dar cuenta de lo que «pasaba por su mente» mientras estudiaban. Una entrevista semi-estructurada y una prueba objetiva. Los resultados fueron analizados a la luz del modelo mixto de procesamiento de información y constructivismo abordado por Winne(1998. Como resultado se encontró una relación significativa entre los niveles de desempeño en el proceso de ARR y el resultado del examen. Igualmente se encontraron bajos niveles de regulación en una parte importante de la muestra y un desfase significativo entre conocimiento declarativo de ARR y desempeño en el mismo

  3. Looking at the label and beyond: the effects of calorie labels, health consciousness, and demographics on caloric intake in restaurants.

    Science.gov (United States)

    Ellison, Brenna; Lusk, Jayson L; Davis, David

    2013-02-08

    Recent legislation has required calorie labels on restaurant menus as a means of improving Americans' health. Despite the growing research in this area, no consensus has been reached on the effectiveness of menu labels. This suggests the possibility of heterogeneity in responses to caloric labels across people with different attitudes and demographics. The purpose of this study was to explore the potential relationships between caloric intake and diners' socio-economic characteristics and attitudes in a restaurant field experiment that systematically varied the caloric information printed on the menus. We conducted a field experiment in a full service restaurant where patrons were randomly assigned to one of three menu treatments which varied the amount of caloric information printed on the menus (none, numeric, or symbolic calorie label). At the conclusion of their meals, diners were asked to complete a brief survey regarding their socio-economic characteristics, attitudes, and meal selections. Using regression analysis, we estimated the number of entrée and extra calories ordered by diners as a function of demographic and attitudinal variables. Additionally, irrespective of the menu treatment to which a subject was assigned, our study identified which types of people are likely to be low-, medium-, and high-calorie diners. Results showed that calorie labels have the greatest impact on those who are least health conscious. Additionally, using a symbolic calorie label can further reduce the caloric intake of even the most health conscious patrons. Finally, calorie labels were more likely to influence the selection of the main entrée as opposed to supplemental items such as drinks and desserts. If numeric calorie labels are implemented (as currently proposed), they are most likely to influence consumers who are less health conscious - probably one of the key targets of this legislation. Unfortunately, numeric labels did little for those consumers who were already

  4. 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

  5. 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.

  6. 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 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.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.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, data suggest that HexCer/LacCers are important mediators of cellular

  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. Violencia con el anciano

    Directory of Open Access Journals (Sweden)

    Rita Campillo Motilva

    2002-08-01

    Full Text Available La violencia doméstica es tan antigua como la humanidad misma y se reconocen la violencia infantil, contra la mujer y al anciano, fundamentalmente; siendo este último grupo una población en ascenso por las mayores expectativas de vida de los últimos años. Como resultado de ello, el número de casos de abuso en el anciano se incrementará y el impacto de este abuso sobre la salud debe ser considerado de forma adecuada. La gama de maltratos es variadísima e incluye el abuso físico, emocional, financiero, sexual, por negligencia, negación a brindarle ayuda y otras formas más. Los ancianos con deterioro cognitivo son los más vulnerables. El médico en la atención primaria de salud es un pilar importante en la prevención y educación de este problema.Domestic violence is as old as humanity itself. Child, women and elderly abuse are mainly recognized. The elderly group is increasing due to the higher life expectancy experimented during the last years. As a result, the number of battered elderly will grow and the impact of this abuse on health should be adequately considered. The range of abuse is very wide and it includes physical, emotional, financial and sexual abuse, negligence, rejection to give assistance and others. The elderly with cognitive deterioration are the most vulnerable. The physician at the primary health care level is an important milestone in the prevention and education of this problem.

  9. DEPURACIÓN ALTERNATIVA, CON APORTE TÉRMICO DE ENERGÍA SOLAR

    Directory of Open Access Journals (Sweden)

    Antoni Martínez-Taberner

    2007-01-01

    Full Text Available La situación del Campus de la UIB, aislado de la ciudad, ligado al tema de la escasez del agua ha permitido el desarrollo de un sistema de depuración in situ de las aguas residuales producidas en las propias instalaciones universitarias. El proceso se desarrolla íntegramente con sistemas de depuración natural en un diseño que combina 3 tecnologías existentes: el lagunaje, los humedales construidos y los filtros verdes arbolados. La innovación se produce en un sistema de regulación térmica del lagunaje para evitar la inversión térmica, que provoca situaciones puntuales de malos olores. Se trata de aprovechar el calor residual de una instalación de climatización solar en un edificio cercano a la laguna, de tal manera que la laguna ejerza de refrigerador del sistema y a la vez aproveche el calor para potenciar la estratifi cación térmica.

  10. 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.

  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. 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.

  13. 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. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Contribution by Lazare and Sadi Carnot to the caloric theory of heat and its inspirative role in thermodynamics

    Czech Academy of Sciences Publication Activity Database

    Šesták, Jaroslav; Mareš, Jiří J.; Hubík, Pavel; Proks, I.

    2009-01-01

    Roč. 97, č. 2 (2009), s. 679-683 ISSN 1388-6150 R&D Projects: GA AV ČR IAA1010404; GA AV ČR IAA100100639 Institutional research plan: CEZ:AV0Z10100521 Keywords : caloric as entropy * Carnot * efficiency * history * thermal analysis * thermodynamics Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.587, year: 2009

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

    Science.gov (United States)

    Griffioen-Roose, Sanne; Smeets, Paul A M; Weijzen, Pascalle L G; van Rijn, Inge; van den Bosch, Iris; de Graaf, Cees

    2013-01-01

    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. 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. 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. 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. 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.

  16. Effects of Low-Dose Non-Caloric Sweetener Consumption on Gut Microbiota in Mice

    Directory of Open Access Journals (Sweden)

    Takashi Uebanso

    2017-06-01

    Full Text Available Abstract: Non-caloric artificial sweeteners (NASs provide sweet tastes to food without adding calories or glucose. NASs can be used as alternative sweeteners for controlling blood glucose levels and weight gain. Although the consumption of NASs has increased over the past decade in Japan and other countries, whether these sweeteners affect the composition of the gut microbiome is unclear. In the present study, we examined the effects of sucralose or acesulfame-K ingestion (at most the maximum acceptable daily intake (ADI levels, 15 mg/kg body weight on the gut microbiome in mice. Consumption of sucralose, but not acesulfame-K, for 8 weeks reduced the relative amount of Clostridium cluster XIVa in feces. Meanwhile, sucralose and acesulfame-K did not increase food intake, body weight gain or liver weight, or fat in the epididymis or cecum. Only sucralose intake increased the concentration of hepatic cholesterol and cholic acid. Moreover, the relative concentration of butyrate and the ratio of secondary/primary bile acids in luminal metabolites increased with sucralose consumption in a dose-dependent manner. These results suggest that daily intake of maximum ADI levels of sucralose, but not acesulfame-K, affected the relative amount of the Clostridium cluster XIVa in fecal microbiome and cholesterol bile acid metabolism in mice.

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

    International Nuclear Information System (INIS)

    Choi, Joon-Seok; Lee, Cheol-Koo

    2013-01-01

    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

  18. [Developing indices for caloric restriction related to World War II--a pilot study].

    Science.gov (United States)

    Vin-Raviv, Neomi; Dekel, Rachel; Barchana, Micha; Linn, Shi; Keinan-Boker, Lital

    2011-04-01

    The vast numbers of studies regarding caloric restriction (CR) and breast cancer risk are based on war-related extreme situations. Studying the impact of CR in Jews during World War II (WW II) is challenging due to its variance and duration. To develop novel research tools in order to assess CR exposure in Jews that occurred more than 60 years ago during WW II. A pilot study based on Israeli women born in Europe in 1926-45, who lived there during WWII. Primary incident breast cancer patients and population-based controls were interviewed using a detailed questionnaire referring to demographic, obstetric factors and WW II experiences. Exposure to WWII-related CR was assessed by several proxy variables based on this information. The individual hunger score was higher in the exposed cases [mean score 141.06 vs. 130.07 in the controls). The same trend was observed for self perceived hunger score (mean score 2.75 in cases vs. 2.40 in controls) and hunger symptoms score (4.89 vs. 3.56, respectively). The novel research tools are appropriate for comparative assessment of CR exposure in case control studies.

  19. 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. Conclusion. A rapid refeeding protocol with the inclusion of phosphate supplementation can safely achieve rapid weight restoration without increased complications associated with refeeding syndrome. PMID:27293884

  20. Caloric restriction and intermittent fasting: Two potential diets for successful brain aging

    Science.gov (United States)

    Martin, Bronwen; Mattson, Mark P.; Maudsley, Stuart

    2008-01-01

    The vulnerability of the nervous system to advancing age is all too often manifest in neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. In this review article we describe evidence suggesting that two dietary interventions, caloric restriction (CR) and intermittent fasting (IF), can prolong the health-span of the nervous system by impinging upon fundamental metabolic and cellular signaling pathways that regulate life-span. CR and IF affect energy and oxygen radical metabolism, and cellular stress response systems, in ways that protect neurons against genetic and environmental factors to which they would otherwise succumb during aging. There are multiple interactive pathways and molecular mechanisms by which CR and IF benefit neurons including those involving insulin-like signaling, FoxO transcription factors, sirtuins and peroxisome proliferator-activated receptors. These pathways stimulate the production of protein chaperones, neurotrophic factors and antioxidant enzymes, all of which help cells cope with stress and resist disease. A better understanding of the impact of CR and IF on the aging nervous system will likely lead to novel approaches for preventing and treating neurodegenerative disorders. PMID:16899414

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

    Science.gov (United States)

    Goes, Vanessa Fernanda; Mello-Carpes, Pâmela Billig; de Oliveira, Lilian Oliveira; Hack, Jaqueline; Magro, Marcela; Bonini, Juliana Sartori

    2014-01-01

    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. PMID:26107841

  2. Caloric Restriction Protects against Lactacystin-Induced Degeneration of Dopamine Neurons Independent of the Ghrelin Receptor

    Directory of Open Access Journals (Sweden)

    Jessica Coppens

    2017-03-01

    Full Text Available Parkinson’s disease (PD is a neurodegenerative disorder, characterized by a loss of dopamine (DA neurons in the substantia nigra pars compacta (SNc. Caloric restriction (CR has been shown to exert ghrelin-dependent neuroprotective effects in the 1-methyl-4-phenyl-1,2,3,6-tetrathydropyridine (MPTP-based animal model for PD. We here investigated whether CR is neuroprotective in the lactacystin (LAC mouse model for PD, in which proteasome disruption leads to the destruction of the DA neurons of the SNc, and whether this effect is mediated via the ghrelin receptor. Adult male ghrelin receptor wildtype (WT and knockout (KO mice were maintained on an ad libitum (AL diet or on a 30% CR regimen. After 3 weeks, LAC was injected unilaterally into the SNc, and the degree of DA neuron degeneration was evaluated 1 week later. In AL mice, LAC injection significanty reduced the number of DA neurons and striatal DA concentrations. CR protected against DA neuron degeneration following LAC injection. However, no differences were observed between ghrelin receptor WT and KO mice. These results indicate that CR can protect the nigral DA neurons from toxicity related to proteasome disruption; however, the ghrelin receptor is not involved in this effect.

  3. Caloric restriction increases ketone bodies metabolism and preserves blood flow in aging brain.

    Science.gov (United States)

    Lin, Ai-Ling; Zhang, Wei; Gao, Xiaoli; Watts, Lora

    2015-07-01

    Caloric restriction (CR) has been shown to increase the life span and health span of a broad range of species. However, CR effects on in vivo brain functions are far from explored. In this study, we used multimetric neuroimaging methods to characterize the CR-induced changes of brain metabolic and vascular functions in aging rats. We found that old rats (24 months of age) with CR diet had reduced glucose uptake and lactate concentration, but increased ketone bodies level, compared with the age-matched and young (5 months of age) controls. The shifted metabolism was associated with preserved vascular function: old CR rats also had maintained cerebral blood flow relative to the age-matched controls. When investigating the metabolites in mitochondrial tricarboxylic acid cycle, we found that citrate and α-ketoglutarate were preserved in the old CR rats. We suggest that CR is neuroprotective; ketone bodies, cerebral blood flow, and α-ketoglutarate may play important roles in preserving brain physiology in aging. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  4. Severe caloric restriction in young women during World War II and subsequent breast cancer risk.

    Science.gov (United States)

    Vin-Raviv, N; Barchana, M; Linn, S; Keinan-Boker, L

    2012-10-01

    The objective of the study was to examine the impact of WWII-related caloric restriction (CR) on subsequent breast cancer (BC) risk based on individual exposure experiences and whether this effect was modified by age at exposure. We compared 65 breast cancer patients diagnosed between 2005-2010 to 200 controls without breast cancer who were all members of various organizations for Jewish WWII survivors in Israel. All participants were Jewish women born in Europe prior to 1945 who lived at least 6 months under Nazi rule during WWII and immigrated to Israel after the war. We estimated CR using a combined index for hunger and used logistic regression models to estimate the association between CR and BC, adjusting for potential confounders. Women who were severely exposed to hunger had an increased risk of BC (OR=5.0, 95% CI= 2.3-10.8) compared to women who were mildly exposed. The association between CR and BC risk was stronger for women who were exposed at a younger age (0-7 years) compared to the risk of BC in women exposed at ≥ 14 years (OR= 2.8, 95% CI=1.3-6.3). Severe exposure to CR is associated with a higher risk for BC decades later, and may be generalized to other cases of severe starvation during childhood that may have long-term effects on cancer in adulthood. © 2012 Blackwell Publishing Ltd.

  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. Central de producción de calor - Madrid – España

    Directory of Open Access Journals (Sweden)

    Laorden Jiménez, J.

    1973-10-01

    Full Text Available The Heat Production Station of the University City Hospital in Madrid is described, after several years operation. The Station is equipped for an output of 13,000,000 kcal/hr, for heating; 1,000,000 kcal/hr, for hospital hot water, and 3,200,000 kcal/hr, for steam at 5 kp/cm2. The different alternatives are presented and the general outline of the solution chosen, as well as a comprehensive list of the materials used.Se describe la Central de Producción de Calor del Hospital Clínico de la Ciudad Universitaria de Madrid, después de algunos años de funcionamiento. La Central está preparada para una producción de 13.000.000 de kcal/h, para calefacción; 1.000.000 de kilocalorías/h, para agua caliente sanitaria, y 3.200.000 kcal/h, para vapor a 5 kp/cm2. Se presentan las diversas alternativas y el esquema general de la solución elegida, así como una extensa relación de ios materiales empleados.

  7. Dynamics of nucleus-nucleus collisions up to 100 MeV/u and caloric curve

    International Nuclear Information System (INIS)

    Peter, J.; Angelique, J.C.; Auger, G.

    1997-01-01

    Using the 4π multidetector array Mur + Tonneau at GANIL made it possible to determine that, at incidence energy 35-95 MeV/u, the fusion (or one main source) cross section is very small in nearly symmetrical light and medium systems. Dissipative binary collisions accompanied by mid-rapidity (participant) emission were found to dominate at all impact parameters. The excitation energy of the reconstructed quasi-projectile was obtained via calorimetry and reaches high values. Using the 4π array INDRA several new features of mid-rapidity emission were revealed: the isotopic composition, mean transverse momentum and apparent temperature do not vary with the impact parameter, whereas the number of emitted nucleons increases with decreasing impact parameter. Mid-rapidity products are more n-rich than quasi-projectile products. Hot quasi-projectiles formed in two reactions were used to study the caloric curve. The apparent temperatures were obtained from several double isotopic yield ratios and slopes of kinetic energy spectra at excitation energy per nucleon ranging up to 24 MeV. Different thermometers give different values, but all of them increase steadily with excitation energy. These data can be explained by calculations assuming a steady increase of the initial temperature with excitation energy, without a plateau which was claimed as evidence for a liquid-gas phase transition. (authors)

  8. 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

    2016-03-01

    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.

  9. Caloric Restriction-Induced Extension of Chronological Lifespan Requires Intact Respiration in Budding Yeast.

    Science.gov (United States)

    Kwon, Young-Yon; Lee, Sung-Keun; Lee, Cheol-Koo

    2017-04-01

    Caloric restriction (CR) has been shown to extend lifespan and prevent cellular senescence in various species ranging from yeast to humans. Many effects of CR may contribute to extend lifespan. Specifically, CR prevents oxidative damage from reactive oxygen species (ROS) by enhancing mitochondrial function. In this study, we characterized 33 single electron transport chain (ETC) gene-deletion strains to identify CR-induced chronological lifespan (CLS) extension mechanisms. Interestingly, defects in 17 of these 33 ETC gene-deleted strains showed loss of both respiratory function and CR-induced CLS extension. On the contrary, the other 16 respiration-capable mutants showed increased CLS upon CR along with increased mitochondrial membrane potential (MMP) and intracellular adenosine triphosphate (ATP) levels, with decreased mitochondrial superoxide generation. We measured the same parameters in the 17 non-respiratory mutants upon CR. CR simultaneously increased MMP and mitochondrial superoxide generation without altering intracellular ATP levels. In conclusion, respiration is essential for CLS extension by CR and is important for balancing MMP, ROS, and ATP levels.

  10. Metabolomics Reveals Metabolically Healthy and Unhealthy Obese Individuals Differ in their Response to a Caloric Challenge.

    Directory of Open Access Journals (Sweden)

    Flavia Badoud

    Full Text Available To determine if metabolically healthy obese (MHO individuals have a different metabolic response to a standardized diet compared to lean healthy (LH and metabolically unhealthy obese (MUO individuals.Thirty adults (35-70 yrs were classified as LH, MHO, and MUO according to anthropometric and clinical measurements. Participants consumed a standardized high calorie meal (~1330 kcal. Blood glucose and insulin were measured at fasting, and 15, 30, 60, 90 and 120 min postprandially. Additional blood samples were collected for the targeted analysis of amino acids (AAs and derivatives, and fatty acids (FAs.The postprandial response (i.e., area under the curve, AUC for serum glucose and insulin were similar between MHO and LH individuals, and significantly lower than MUO individuals (p < 0.05. Minor differences were found in postprandial responses for AAs between MHO and MUO individuals, while three polyunsaturated FAs (linoleic acid, γ-linolenic acid, arachidonic acid showed smaller changes in serum after the meal in MHO individuals compared to MUO. Fasting levels for various AAs (notably branched-chain AA and FAs (e.g., saturated myristic and palmitic acids were found to correlate with glucose and insulin AUC.MHO individuals show preserved insulin sensitivity and a greater ability to adapt to a caloric challenge compared to MUO individuals.

  11. 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.

  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. Laser desensitization of austenitic stainless steel weld AHZ. Desensibilizacion con Laser de la zona afectada por el calor (ZAC) en aceros inoxidables austeniticos

    Energy Technology Data Exchange (ETDEWEB)

    Lee, C.H.; Kim, K.C.; Chang, R.W. (Welding Research Center Research Institute of Industrial Science and Technology, Pohang (Korea, Republic of))

    1994-01-01

    This paper addressed the fundamental understanding of sensitization phenomena in the weld HAZ of austenitic stainless steel and a method of desensitization utilizing LASER, without degradation of other corrosion resistance (pitting resistance). Sensitization in the weld HAZ was due to a formation of CR depleted zone along grain boundaries and twin boundaries by precipitation of Cr[sub 2]3C[sub 6] which contains 70-80% Cr and a small amount of Fe having a cubic-cubic relationship with the austenite matrix. Common morphologies of carbides were found to be of bar and globular shapes. As the holding time increased, carbides with coarsened globular (iodomorph) and dendrite shapes were also found. However, there was no significant variation in the composition of carbides and width of the Cr depleted zone with morphology. Laser desensitization could be obtained with a proper choice of the beam power and travel speed under a constant beam size. As long as the beam density reached a critical amount, carbides and Cr depleted zone completed zone completely disappeared. The critical travel speed increased with higher beam power, but was constant regardless of the original degree of sensitization. Pitting resistance of the LASER desensitized base metal and HAZ appeared to be far superior to that found in the sensitized condition. The protection potential in the hysteresis loop test was very sensitive to the degree of sensitization, revealing that the protection potential was dependent upon the propagation of the pits through the Cr depleted grain boundaries. (Author) 10 refs.

  14. [Index of Nutritional Purchasing Power Parity: comparison of caloric costs of a healthy versus an unhealthy diet].

    Science.gov (United States)

    Mendoza Velázquez, Alfonso

    2012-01-01

    Develop the Index of Nutritional Purchasing Power Parity (Nut3-CiO) as an instrument to compare the caloric costs of a healthy versus an unhealthy diet between regions or cities in a country over time. Indices of caloric prices were constructed and the "law of one price" was used to derive the Nut3-CiO index. Caloric inflation rates were obtained using basic descriptive statistics. The Nut3-CiO was applied in the major cities of Mexico during the period from January 1996 to December 2010. The statistical behavior of the Nut3-CiO revealed that, in Mexican cities, products for a typical diet are less expensive than products for a healthy diet. The findings showed a cyclical behavior to the index, a high correlation between inflation for the typical diet and inflation for the market basket, and a high persistence of prices. The Nut3-CiO index makes it possible to periodically compare the price differential of two types of diets-typical and healthy-between cities in a single country. This instrument could help health authorities identify the cities where it is easier or more difficult for consumers to access a typical or healthy diet in terms of cost. Furthermore, it makes it possible to estimate the percentage adjustment necessary in each city to attain levels of nutritional purchasing power parity.

  15. 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.

  16. Sweet taste of saccharin induces weight gain without increasing caloric intake, not related to insulin-resistance in Wistar rats.

    Science.gov (United States)

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

    2016-01-01

    In a previous study, we showed that saccharin can induce weight gain when compared with sucrose in Wistar rats despite similar total caloric intake. We now question whether it could be due to the sweet taste of saccharin per se. We also aimed to address if this weight gain is associated with insulin-resistance and to increases in gut peptides such as leptin and PYY in the fasting state. In a 14 week experiment, 16 male Wistar rats received either saccharin-sweetened yogurt or non-sweetened yogurt daily in addition to chow and water ad lib. We measured daily food intake and weight gain weekly. At the end of the experiment, we evaluated fasting leptin, glucose, insulin, PYY and determined insulin resistance through HOMA-IR. Cumulative weight gain and food intake were evaluated through linear mixed models. Results showed that saccharin induced greater weight gain when compared with non-sweetened control (p = 0.027) despite a similar total caloric intake. There were no differences in HOMA-IR, fasting leptin or PYY levels between groups. We conclude that saccharin sweet taste can induce mild weight gain in Wistar rats without increasing total caloric intake. This weight gain was not related with insulin-resistance nor changes in fasting leptin or PYY in Wistar rats. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. The association between measurement sites of visceral adipose tissue and cardiovascular risk factors after caloric restriction in obese Korean women.

    Science.gov (United States)

    Lee, Hye-Ok; Yim, Jung-Eun; Lee, Jeong-Sook; Kim, Young-Seol; Choue, Ryowon

    2013-02-01

    Quantities as well as distributions of adipose tissue (AT) are significantly related to cardiovascular disease (CVD) risk factors and can be altered with caloric restriction. This study investigated which cross-sectional slice location of AT is most strongly correlated with changes in CVD risk factors after caloric restriction in obese Korean women. Thirty-three obese pre-menopausal Korean women (32.4 ± 8.5 yrs, BMI 27.1 ± 2.3 kg/m(2)) participated in a 12 weeks caloric restriction program. Subcutaneous adipose tissue (SAT) and visceral adipose tissue (VAT) were measured using computed tomography (CT) scans at the sites of L2-L3, L3-L4, and L4-L5. Fasting serum levels of glucose, insulin, triglyceride, total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), leptin and homeostasis model assessment-insulin resistance (HOMA-IR) were observed. Pearson's partial correlation coefficients were used to assess the relationship between AT measurement sites and changes in CVD risk factors after calorie restriction. When calories were reduced by 350 kcal/day for 12 weeks, body weight (-2.7%), body fat mass (-8.2%), and waist circumference (-5.8%) all decreased (P restriction, serum levels of glucose (-4.6%), TC (-6.2%), LDL-C (-5.3%), leptin (-17.6%) and HOMA-IR (-18.2%) decreased significantly (P restriction.

  18. 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

  19. 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)

    1991-12-31

    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

  20. 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.

  1. Acne polimorfo: tratamiento con Implacen

    Directory of Open Access Journals (Sweden)

    Rubén Pérez Armas

    1995-06-01

    Full Text Available Se realiza el estudio de 40 pacientes con acné polimorfo, los que fueron atendidos en la Consulta de Dermatología del Hospital Provincial Clinicoquirúrgico Docente "Celia Sánchez Manduley", en el período comprendido de enero de 1988 a diciembre de 1989. Se revisa la literatura médica sobre los diversos métodos y medicamentos utilizados en la terapéutica de esta dermatosis. Se describe el esquema de tratamiento empleado con implacén en 30 pacientes; los 10 restantes se trataron con placebo; se compara dicho esquema con los tradicionales y se observan mejores resultados con nuestro estudio. Se destaca la ausencia de recaídas, así como el resultado del tratamiento de acuerdo con el sexo.A study was performed in 40 patients presenting with polymorphic acne who were attended in the Dermatology Department of "Celia Sánchez Manduley" Clinicosurgical and Teaching Hospital from January, 1988 to December, 1989. A review of the literature was made seeking for the different methods and drugs used for the treatment of this dermatosis. The treatment schedule with the use of implacen in 30 patients is described. Such therapeutic schedule was compared with traditional ones and better results were observed with the use of implacen. The fact that there were no relapses is highlighted, as well as the result of treatment according to sex.

  2. Using eastern gamagrass to construct diets that limit intake and caloric density for dairy replacement heifers.

    Science.gov (United States)

    Coblentz, W K; Hoffman, P C; Esser, N M; Bertram, M G

    2012-10-01

    Previous research has shown that eastern gamagrass (EGG; Tripsacum dactyloides L.) will survive winter climatic conditions common throughout central Wisconsin, and will produce yields of dry matter (DM) ranging approximately from 7,000 to 10,000 kg/ha annually when managed with a 1-cut harvest system. The objective of this research was to determine whether the fibrous nature of this perennial warm-season grass could be effective in reducing the caloric density and DMI of corn silage/alfalfa haylage diets for replacement dairy heifers. A total of 120 Holstein dairy heifers were blocked by body weight (heavy, 424 ± 15.9 kg; medium, 369 ± 11.8 kg; light, 324 ± 22.4 kg), and then assigned to 15 individual pens containing 8heifers each. Eastern gamagrass forage was harvested, ensiled, and subsequently incorporated into blended corn silage/alfalfa haylage diets at rates of 0, 9.1, 18.3, or 27.4% of the total dietary DM (EGG0, EGG9, EGG18, and EGG27, respectively). These diets were offered during a 105-d evaluation period for ad libitum intake; however, the EGG0 diet also was offered on a limit-fed basis (LF), which was set at 85% of the voluntary intake of EGG0. Serial additions of EGG increased concentrations of neutral detergent fiber in blended diets from 39.6 (EGG0) to 48.7% (EGG27), and simultaneously reduced corresponding estimates of total digestible nutrients (TDN) from 68.2 to 61.3%, and net energy for gain from 1.07 to 0.83 Mcal/kg. Dry matter intakes for all diets offered ad libitum were greater than observed for LF (9.06 vs. 8.07 kg/d); however, DM intakes for diets containing EGG were reduced relative to EGG0 (9.40 vs. 8.94 kg/d). Similarly, intakes of TDN were greater for diets offered for ad libitum intake than for LF (5.84 vs. 5.50 kg/d); however, inclusion of EGG reduced TDN intakes relative to EGG0 (6.41 vs. 5.65 kg/d). This reduction was explained by both linear and quadratic effects of the inclusion rate of EGG in the diet. Over the 105-d trial

  3. Six and 12 Weeks of Caloric Restriction Increases β Cell Function and Lowers Fasting and Postprandial Glucose Concentrations in People with Type 2 Diabetes123

    Science.gov (United States)

    Sathananthan, Matheni; Shah, Meera; Edens, Kim L; Grothe, Karen B; Piccinini, Francesca; Farrugia, Luca P; Micheletto, Francesco; Man, Chiara Dalla; Cobelli, Claudio; Rizza, Robert A; Camilleri, Michael; Vella, Adrian

    2015-01-01

    Background: Caloric restriction alone has been shown to improve insulin action and fasting glucose metabolism; however, the mechanism by which this occurs remains uncertain. Objective: We sought to quantify the effect of caloric restriction on β cell function and glucose metabolism in people with type 2 diabetes. Methods: Nine subjects (2 men, 7 women) with type 2 diabetes [BMI (in kg/m2): 40.6 ± 1.4; age: 58 ± 3 y; glycated hemoglobin: 6.9% ± 0.2%] were studied using a triple-tracer mixed meal after withdrawal of oral diabetes therapy. The oral minimal model was used to measure β cell function. Caloric restriction limited subjects to a pureed diet (restriction. Results: Fasting glucose concentrations decreased significantly from baseline after 6 wk of caloric restriction with no further reduction after a further 6 wk of caloric restriction (9.8 ± 1.3, 5.9 ± 0.2, and 6.2 ± 0.3 mmol/L at baseline and after 6 and 12 wk of caloric restriction, respectively; P = 0.01) because of decreased fasting endogenous glucose production (EGP: 20.4 ± 1.1, 16.2 ± 0.8, and 17.4 ± 1.1 μmol · kg−1 · min−1 at baseline and after 6 and 12 wk of caloric restriction, respectively; P = 0.03). These changes were accompanied by an improvement in β cell function measured by the disposition index (189 ± 51, 436 ± 68, and 449 ± 67 10−14 dL · kg−1 · min−2 · pmol−1 at baseline and after 6 and 12 wk of caloric restriction, respectively; P = 0.01). Conclusions: Six weeks of caloric restriction lowers fasting glucose and EGP with accompanying improvements in β cell function in people with type 2 diabetes. An additional 6 wk of caloric restriction maintained the improvement in glucose metabolism. This trial was registered at clinicaltrials.gov as NCT01094054. PMID:26246321

  4. [Low caloric value and high salt content in the meals served in school canteens].

    Science.gov (United States)

    Paiva, Isabel; Pinto, Carlos; Queirós, Laurinda; Meister, Maria Cristina; Saraiva, Margarida; Bruno, Paula; Antunes, Delfina; Afonso, Manuel

    2011-01-01

    School lunch can contribute to aggravate food quality, by excess or deficiency, or it can contribute to compensate and alleviate them. This school meal should be an answer to combating the epidemic of obesity, and to feed some grace children. The objective was to study the nutritional composition of catering in canteens of public schools, from Northern municipalities in the District of Porto: Vila do Conde, Póvoa de Varzim, Santo Tirso and Trofa. Meals were subjected to laboratory analysis. Thirty two meals, four per each school were analysed, reference values for the analysis of the nutritional composition of meals were dietary reference intakes (USA) and eating well at school (UK). The average energy meal content was 447 kcal and the median 440 kcal (22% of daily calories). The average values of nutrients, per meal, were: lipids 9, 8 g, carbohydrate 65,7 g and proteins 24,0 g. In average the contribution for the meal energy was: 20% fat, 59% carbohydrate and 21% protein. In more than 75% of meals the contribution of lipid content was below the lower bound of the reference range. The average content of sodium chloride per meal was 3.4 g, and the confidence interval 95% to average 3.0 to 3.8 g, well above the recommended maximum value of 1.5 grams. The average content fiber per meal was 10.8 g higher than the minimum considered appropriate. In conclusion, the value low caloric meals was mainly due to the low fat content, and content salt of any of the components of the meal was very high.

  5. A randomized nutrition counseling intervention in pediatric leukemia patients receiving steroids results in reduced caloric intake.

    Science.gov (United States)

    Li, Rhea; Donnella, Hayley; Knouse, Phillip; Raber, Margaret; Crawford, Karla; Swartz, Maria C; Wu, Jimin; Liu, Diane; Chandra, Joya

    2017-02-01

    Quality of life in survivors of pediatric acute lymphocytic leukemia (ALL) can be compromised by chronic diseases including increased risk of second cancers, cardiovascular disease, and diabetes. Overweight or obesity further increases these risks. Steroids are a component of chemotherapy for ALL, and weight gain is a common side effect. To impact behaviors associated with weight gain, we conducted a randomized nutrition counseling intervention in ALL patients on treatment. ALL patients on a steroid-based treatment regimen at the MD Anderson Children's Cancer Hospital were recruited and randomized into control or intervention groups. The control group received standard care and nutrition education materials. The intervention group received monthly one-on-one nutrition counseling sessions, consisting of a baseline and 12 follow-up visits. Anthropometrics, dietary intake (3-day 24-hr dietary recalls) and oxidative stress measures were collected at baseline, 6 months, and postintervention. Dietary recall data were analyzed using the Nutrition Data System for Research. Twenty-two patients (median age 11.5 years), all in the maintenance phase of treatment, were recruited. The intervention group (n = 12) reported significantly lower calorie intake from baseline to 12-month follow-up and significant changes in glutamic acid and selenium intake (P < 0.05). Waist circumference was significantly associated with calorie, vitamin E, glutamic acid, and selenium intake. A year-long dietary intervention was effective at reducing caloric intake in pediatric ALL patients receiving steroid-based chemotherapy, indicating that this is a modality that can be built upon for obesity prevention and management. © 2016 Wiley Periodicals, Inc.

  6. Effect of exercise on the caloric intake of breast cancer patients undergoing treatment

    Directory of Open Access Journals (Sweden)

    C.L. Battaglini

    2008-08-01

    Full Text Available The purpose of this study was to examine the effects of an exercise intervention on the total caloric intake (TCI of breast cancer patients undergoing treatment. A secondary purpose was to determine whether or not a relationship existed between changes in TCI, body fat composition (%BF, and fatigue during the study, which lasted 6 months. Twenty females recently diagnosed with breast cancer, scheduled to undergo chemotherapy or radiation, were assigned randomly to an experimental (N = 10 or control group (N = 10. Outcome measures included TCI (3-day food diary, %BF (skinfolds, and fatigue (revised Piper Fatigue Scale. Each exercise session was conducted as follows: initial cardiovascular activity (6-12 min, followed by stretching (5-10 min, resistance training (15-30 min, and a cool-down (approximately 8 min. Significant changes in TCI were observed among groups (F1,18 = 8.582; P = 0.009, at treatments 2 and 3, and at the end of the study [experimental (1973 ± 419, control (1488 ± 418; experimental (1946 ± 437, control (1436 ± 429; experimental (2315 ± 455, control (1474 ± 294, respectively]. A significant negative correlation was found (Spearman rho(18 = -0.759; P < 0.001 between TCI and %BF and between TCI and fatigue levels (Spearman rho(18 = -0.541; P = 0.014 at the end of the study. In conclusion, the results of this study suggest that an exercise intervention administered to breast cancer patients undergoing medical treatment may assist in the mitigation of some treatment side effects, including decreased TCI, increased fatigue, and negative changes in body composition.

  7. No effect of caloric restriction on salivary cortisol levels in overweight men and women.

    Science.gov (United States)

    Tam, Charmaine S; Frost, Elizabeth A; Xie, Wenting; Rood, Jennifer; Ravussin, Eric; Redman, Leanne M

    2014-02-01

    The effect of weight loss by diet or diet and exercise on salivary cortisol levels, a measure of hypothalamic pituitary adrenal activity, in overweight individuals is not known. The objective was to test the hypothesis that 24 weeks of moderate caloric restriction (CR) (25%) by diet or diet and aerobic exercise would alter morning and diurnal salivary cortisol levels. Randomized control trial in an institutional research center. Thirty-five overweight (BMI: 27.8±0.7 kg/m(2)) but otherwise healthy participants (16 M/19 F). Participants were randomized to either calorie restriction (CR: 25% reduction in energy intake, n=12), calorie restriction+exercise (CR+EX: 12.5% reduction in energy intake+12.5% increase in exercise energy expenditure, n=12) or control (healthy weight-maintenance diet, n=11) for 6 months. Salivary cortisol measured at 8:00, 8:30, 11:00, 11:30, 12:30, 13:00, 16:00 and 16:30. Morning cortisol was defined as the mean cortisol concentration at 08:00 and 08:30. Diurnal cortisol was calculated as the mean of the 8 cortisol measures across the day. In the whole cohort, higher morning and diurnal cortisol levels were associated with impaired insulin sensitivity (morning: P=0.004, r(2)=0.24; diurnal: P=0.02, r(2)=0.15). Using mixed model analysis, there was no significant effect of group, time or sex on morning or diurnal cortisol levels. A 10% weight loss with a 25% CR diet alone or with exercise did not impact morning or diurnal salivary cortisol levels. © 2013.

  8. Balanced Caloric Restriction Minimizes Changes Caused by Aging on the Colonic Myenteric Plexus.

    Science.gov (United States)

    Mari, Renata de Britto; Stabille, Sandra Regina; de Faria, Haroldo Garcia; Pereira, Joice Naiara Bertaglia; Guimarães, Juliana Plácido; Marinsek, Gabriela Pustiglione; de Souza, Romeu Rodrigues

    2018-05-04

    Aging can promote significant morphofunctional changes in the gastrointestinal tract (GIT). Regulation of GIT motility is mainly controlled by the myenteric neurons of the enteric nervous system. Actions that aim at decreasing the aging effects in the GIT include those related to diet, with caloric restriction (CR). The CR is achieved by controlling the amount of food or by manipulating the components of the diet. Therefore, the objective of this study was to evaluate different levels of CR on the plasticity of nicotinamide adenine dinucleotide phosphate- (NADPH-) reactive myenteric neurons in the colon of Wistar rats during the aging process using ultrastructural (transmission electron microscopy) and morphoquantitative analysis. Wistar male rats (Rattus norvegicus) were distributed into 4 groups (n = 10/group): C, 6-month-old animals; SR, 18-month-old animals fed a normal diet; CRI, 18-month-old animals fed a 12% CR diet; CRII, 18-month-old animals fed a 31% CR diet. At 6 months of age, animals were transferred to the laboratory animal facility, where they remained until 18 months of age. Animals of the CRI and CRII groups were submitted to CR for 6 months. In the ultrastructural analysis, a disorganization of the periganglionar matrix with the aging was observed, and this characteristic was not observed in the animals that received hypocaloric diet. It was observed that the restriction of 12.5% and 31% of calories in the diet minimized the increase in density and cell profile of the reactive NADPH neurons, increased with age. This type of diet may be adapted against gastrointestinal disturbances that commonly affect aging individuals.

  9. 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.

  10. Habitual sleep variability, not sleep duration, is associated with caloric intake in adolescents.

    Science.gov (United States)

    He, Fan; Bixler, Edward O; Berg, Arthur; Imamura Kawasawa, Yuka; Vgontzas, Alexandros N; Fernandez-Mendoza, Julio; Yanosky, Jeff; Liao, Duanping

    2015-07-01

    The objective of this study was to investigate the associations between objectively measured habitual sleep duration (HSD), habitual sleep variability (HSV), and energy and snack intake in adolescents. We used data from 324 adolescents who participated in the Penn State Child Cohort follow-up examination. Actigraphy was used over seven consecutive nights to estimate nightly sleep duration. The seven-night mean and standard deviation of sleep duration were used to represent HSD and HSV, respectively. The Youth/Adolescent Food Frequency Questionnaire was used to obtain the daily average total energy, protein, fat, and carbohydrate intake, and number of snacks consumed. Linear regression models were used to investigate the associations between habitual sleep patterns and caloric, protein, fat, and carbohydrate intake. Proportional odds models were used to associate habitual sleep patterns with snack consumption. After adjusting for age, sex, race, body mass index (BMI) percentile, and smoking status, an increased HSV was associated with a higher energy intake, particularly from fat and carbohydrate. For example, with a 1-h increase in HSV, there was a 170 (66)-kcal increase in the daily total energy intake. An increased HSV was also related to increased snack consumption, especially snacks consumed after dinner. For instance, a 1-h increase in HSV was associated with 65% and 94% higher odds of consuming more snacks after dinner during school/workdays and weekends/vacation days, respectively. Neither energy intake nor snack consumption was significantly related to HSD. High habitual sleep variability, not habitual sleep duration, is related to increased energy and food consumption in adolescents. Maintaining a regular sleep pattern may decrease the risk of obesity in adolescents. Copyright © 2015 Elsevier B.V. All rights reserved.

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

    International Nuclear Information System (INIS)

    Ragossnig, A.M.

    2001-05-01

    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)

  12. 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.

  13. Calibration of a Fusion Experiment to Investigate the Nuclear Caloric Curve

    Science.gov (United States)

    Keeler, Ashleigh

    2017-09-01

    In order to investigate the nuclear equation of state (EoS), the relation between two thermodynamic quantities can be examined. The correlation between the temperature and excitation energy of a nucleus, also known as the caloric curve, has been previously observed in peripheral heavy-ion collisions to exhibit a dependence on the neutron-proton asymmetry. To further investigate this result, fusion reactions (78Kr + 12C and 86Kr + 12C) were measured; the beam energy was varied in the range 15-35 MeV/u in order to vary the excitation energy. The light charged particles (LCPs) evaporated from the compound nucleus were measured in the Si-CsI(TI)/PD detector array FAUST (Forward Array Using Silicon Technology). The LCPs carry information about the temperature. The calibration of FAUST will be described in this presentation. The silicon detectors have resistive surfaces in perpendicular directions to allow position measurement of the LCP's to better than 200 um. The resistive nature requires a position-dependent correction to the energy calibration to take full advantage of the energy resolution. The momentum is calculated from the energy of these particles, and their position on the detectors. A parameterized formula based on the Bethe-Bloch equation was used to straighten the particle identification (PID) lines measured with the dE-E technique. The energy calibration of the CsI detectors is based on the silicon detector energy calibration and the PID. A precision slotted mask enables the relative positions of the detectors to be determined. DOE Grant: DE-FG02-93ER40773 and REU Grant: PHY - 1659847.

  14. Potencial de secado de yuca con aire natural y energía solar

    Directory of Open Access Journals (Sweden)

    Alfonso Parra Coronado

    1990-01-01

    Full Text Available En este trabajo se presentan los resultados de estudios del potencial de secado de productos agropecuarios con aire natural y energía solar de regiones tropicales, considerando el caso específico de la yuca. La evaluación del potencial de secado de una región se basa en el uso de un programa de computador  Simulación matemática, mediante el cual se obtienen los valores del caudal mínimo de aire requerido para secar el producto antes que éste alcance un nivel de deterioro preestablecido. Otros elementos metodológicos incluyen: manejo de la información meteorológica, mes crítico, patrón de agitación del producto, hora de iniciación del secado, patrón de operación del ventilador, uso de calor suplementario (energía solar e interpretación de los resultados con el fin de optimizar el sistema. Se presentan mapas para Colombia de líneas isocaudales e isoáreas de colector solar plano, con base en los cuales se puede obtener fácilmente la información requerida para el diseño de sistemas de secado de yuca a baja temperatura.

  15. 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.

  16. 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.

  17. Estrategia en la determinación del factor de forma de radiación ilustrado con el sistema plano-esfera

    Directory of Open Access Journals (Sweden)

    Héctor Armando Durán Peralta

    2012-04-01

    Full Text Available En el diseño de hornos y dispositivos que calientan o enfrían sistemas mediante radiación se necesita calcular el factor de forma, el cual permite determinar la transferencia de calor por radiación entre superficies que estén a distinta temperatura. Generalmente, en los textos que tratan de transferencia de calor se deduce y muestra la ecuación para obtener el factor de forma entre dos superficies que intercambian calor por radiación para configuraciones muy sencillas, pero no se enseña cómo se hace el cálculo para geometrías y configuraciones un poco más complejas. Mediante este documento se pretende dar –con fines netamente académicos– una estrategia para calcular el factor de forma de otras configuraciones, mostrando dicha estrategia al desarrollar un caso particular, como el cálculo del factor de forma plano-esfera.

  18. 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.

  19. 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

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

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    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

  1. Soluble Fermentable Dietary Fibre (Pectin) Decreases Caloric Intake, Adiposity and Lipidaemia in High-Fat Diet-Induced Obese Rats

    Science.gov (United States)

    Adam, Clare L.; Thomson, Lynn M.; Williams, Patricia A.; Ross, Alexander W.

    2015-01-01

    Consumption of a high fat diet promotes obesity and poor metabolic health, both of which may be improved by decreasing caloric intake. Satiety-inducing ingredients such as dietary fibre may be beneficial and this study investigates in diet-induced obese (DIO) rats the effects of high or low fat diet with or without soluble fermentable fibre (pectin). In two independently replicated experiments, young adult male DIO rats that had been reared on high fat diet (HF; 45% energy from fat) were given HF, low fat diet (LF; 10% energy from fat), HF with 10% w/w pectin (HF+P), or LF with 10% w/w pectin (LF+P) ad libitum for 4 weeks (n = 8/group/experiment). Food intake, body weight, body composition (by magnetic resonance imaging), plasma hormones, and plasma and liver lipid concentrations were measured. Caloric intake and body weight gain were greatest in HF, lower in LF and HF+P, and lowest in the LF+P group. Body fat mass increased in HF, was maintained in LF, but decreased significantly in LF+P and HF+P groups. Final plasma leptin, insulin, total cholesterol and triglycerides were lower, and plasma satiety hormone PYY concentrations were higher, in LF+P and HF+P than in LF and HF groups, respectively. Total fat and triglyceride concentrations in liver were greatest in HF, lower in LF and HF+P, and lowest in the LF+P group. Therefore, the inclusion of soluble fibre in a high fat (or low fat) diet promoted increased satiety and decreased caloric intake, weight gain, adiposity, lipidaemia, leptinaemia and insulinaemia. These data support the potential of fermentable dietary fibre for weight loss and improving metabolic health in obesity. PMID:26447990

  2. Moderate caloric restriction during gestation in rats alters adipose tissue sympathetic innervation and later adiposity in offspring.

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    Ana Paula García

    Full Text Available Maternal prenatal undernutrition predisposes offspring to higher adiposity in adulthood. Mechanisms involved in these programming effects, apart from those described in central nervous system development, have not been established. Here we aimed to evaluate whether moderate caloric restriction during early pregnancy in rats affects white adipose tissue (WAT sympathetic innervation in the offspring, and its relationship with adiposity development. For this purpose, inguinal and retroperitoneal WAT (iWAT and rpWAT, respectively were analyzed in male and female offspring of control and 20% caloric-restricted (from 1-12 d of pregnancy (CR dams. Body weight (BW, the weight, DNA-content, morphological features and the immunoreactive tyrosine hydroxylase and Neuropeptide Y area (TH+ and NPY+ respectively, performed by immunohistochemistry of both fat depots, were studied at 25 d and 6 m of age, the latter after 2 m exposure to high fat diet. At 6 m of life, CR males but not females, exhibited greater BW, and greater weight and total DNA-content in iWAT, without changes in adipocytes size, suggesting the development of hyperplasia in this depot. However, in rpWAT, CR males but not females, showed larger adipocyte diameter, with no changes in DNA-content, suggesting the development of hypertrophy. These parameters were not different between control and CR animals at the age of 25 d. In iWAT, both at 25 d and 6 m, CR males but not females, showed lower TH(+ and NPY(+, suggesting lower sympathetic innervation in CR males compared to control males. In rpWAT, at 6 m but not at 25 d, CR males but not females, showed lower TH(+ and NPY(+. Thus, the effects of caloric restriction during gestation on later adiposity and on the differences in the adult phenotype between internal and subcutaneous fat depots in the male offspring may be associated in part with specific alterations in sympathetic innervation, which may impact on WAT architecture.

  3. ISOTERMAS E CALOR ISOSTÉRICO DE ADSORÇÃO DA ÁGUA DO AMIDO DE QUINOA

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    AUGUSTO PUMACAHUA RAMOS

    2017-07-01

    Full Text Available A quinoa possui mais de 60% de amido, sendo uma alternativa de extração e comercialização. Para isto é necessário conhecer o comportamento do amido frente à temperatura e umidade relativa do ar. O objetivo desta pesquisa foi avaliar as isotermas de adsorção do amido de quinoa em cinco temperaturas (20, 30, 40, 50 e 60ºC e dez atividades de água (0,036 a 0,907. Os pontos experimentais foram ajustados aos modelos matemáticos GAB, Oswin, Henderson, Peleg e Ferro-Foltan. Foram determinadas as energias de ativação da adsorção da água pelas constantes do modelo GAB e o calor isostérico pelo modelo de Peleg. As isotermas mostraram ser do tipo II na classificação de Brunauer. Os teores de água da monocamada (Xm determinados pelo modelo de GAB variaram de 7,90% a 10,38% base seca (b.s. para temperaturas de 60 e 20°C e as energias de ativação obtidas pelas constantes Xm, C e K do modelo de GAB foram de 300; 160 e 6 kJ/kg, respectivamente. O calor isostérico de adsorção foi de 3732 kJ/kg para umidade de equilíbrio de 0,5% b.s. e diminuiu com o aumento da umidade até valor próximo ao calor latente de vaporização da água pura a 36% b.s. As propriedades determinadas são características de amidos com elevado teor de amilopectina.

  4. con dietas suplementadas con Cromo-L-metionina

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    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

  5. 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

  6. Effects of age and caloric restriction in the vascular response of renal arteries to endothelin-1 in rats.

    Science.gov (United States)

    Amor, Sara; García-Villalón, Angel Luis; Rubio, Carmen; Carrascosa, Jose Ma; Monge, Luis; Fernández, Nuria; Martín-Carro, Beatriz; Granado, Miriam

    2017-02-01

    Cardiovascular alterations are the most prevalent cause of impaired physiological function in aged individuals with kidney being one the most affected organs. Aging-induced alterations in renal circulation are associated with a decrease in endothelium-derived relaxing factors such as nitric oxide (NO) and with an increase in contracting factors such as endothelin-1(ET-1). As caloric restriction (CR) exerts beneficial effects preventing some of the aging-induced alterations in cardiovascular system, the aim of this study was to analyze the effects of age and caloric restriction in the vascular response of renal arteries to ET-1 in aged rats. Vascular function was studied in renal arteries from 3-month-old Wistar rats fed ad libitum (3m) and in renal arteries from 8-and 24-month-old Wistar rats fed ad libitum (8m and 24m), or subjected to 20% caloric restriction during their three last months of life (8m-CR and 24m-CR). The contractile response to ET-1 was increased in renal arteries from 8m and 24m compared to 3m rats. ET-1-induced contraction was mediated by ET-A receptors in all experimental groups and also by ET-B receptors in 24m rats. Caloric restriction attenuated the increased contraction to ET-1 in renal arteries from 8m but not from 24m rats possibly through NO release proceeding from ET-B endothelial receptors. In 24m rats, CR did not attenuate the aging-increased response of renal arteries to ET-1, but it prevented the aging-induced increase in iNOS mRNA levels and the aging-induced decrease in eNOS mRNA levels in arterial tissue. In conclusion, aging is associated with an increased response to ET-1 in renal arteries that is prevented by CR in 8m but not in 24m rats. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Atenuación del estrés por calor en vacuno lechero: nebulización

    OpenAIRE

    Mena Guerrero, Y.; Serradilla Manrique, J.M.; Gómez Cabrera, Augusto

    1993-01-01

    Misting is one of the methods which has been proven to be effective in reducing heat stress in dairy cows under very dry and hot weather conditions. We have tested the system in the Guadalquivir Valley. We measured the rectal temperature and respiratory frecuency of heat stressed animals, before and after receiving the cooling treatment. The system did not reduce the body temperature La nebulización de agua es uno de los métodos usados para reducir los sintómas de estrés por calor en ganad...

  8. 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

  9. A molecular mechanism for diacylglycerol-mediated promotion of negative caloric balance

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    Yanai H

    2009-12-01

    study demonstrated that 1-monoacylglycerol, a digestive product of DAG, increases serotonin release from the Caco-2 cells, and enhances expression of genes associated with β-oxidation, FA metabolism, and thermogenesis, and that serotonin increases expression of these genes, proposing a novel molecular mechanism for DAG-mediated promotion of negative caloric balance.Keywords: diacylglycerol, energy expenditure, intestine, serotonin, triacylglycerol

  10. Chemotherapy for isolated locoregional recurrence of breast cancer (CALOR): a randomised trial.

    Science.gov (United States)

    Aebi, Stefan; Gelber, Shari; Anderson, Stewart J; Láng, István; Robidoux, André; Martín, Miguel; Nortier, Johan W R; Paterson, Alexander H G; Rimawi, Mothaffar F; Cañada, José Manuel Baena; Thürlimann, Beat; Murray, Elizabeth; Mamounas, Eleftherios P; Geyer, Charles E; Price, Karen N; Coates, Alan S; Gelber, Richard D; Rastogi, Priya; Wolmark, Norman; Wapnir, Irene L

    2014-02-01

    Patients with isolated locoregional recurrences (ILRR) of breast cancer have a high risk of distant metastasis and death from breast cancer. We aimed to establish whether adjuvant chemotherapy improves the outcome of such patients. The CALOR trial was a pragmatic, open-label, randomised trial that accrued patients with histologically proven and completely excised ILRR after unilateral breast cancer who had undergone a mastectomy or lumpectomy with clear surgical margins. Eligible patients were enrolled from hospitals worldwide and were centrally randomised (1:1) to chemotherapy (type selected by the investigator; multidrug for at least four courses recommended) or no chemotherapy, using permuted blocks, and stratified by previous chemotherapy, oestrogen-receptor and progesterone-receptor status, and location of ILRR. Patients with oestrogen-receptor-positive ILRR received adjuvant endocrine therapy, radiation therapy was mandated for patients with microscopically involved surgical margins, and anti-HER2 therapy was optional. The primary endpoint was disease-free survival. All analyses were by intention to treat. This study is registered with ClinicalTrials.gov, number NCT00074152. From Aug 22, 2003, to Jan 31, 2010, 85 patients were randomly assigned to receive chemotherapy and 77 were assigned to no chemotherapy. At a median follow-up of 4·9 years (IQR 3·6-6 ·0), 24 (28%) patients had disease-free survival events in the chemotherapy group compared with 34 (44%) in the no chemotherapy group. 5-year disease-free survival was 69% (95% CI 56-79) with chemotherapy versus 57% (44-67) without chemotherapy (hazard ratio 0·59 [95% CI 0·35-0·99]; p=0·046). Adjuvant chemotherapy was significantly more effective for women with oestrogen-receptor-negative ILRR (pinteraction=0·046), but analyses of disease-free survival according to the oestrogen-receptor status of the primary tumour were not statistically significant (pinteraction=0·43). Of the 81 patients who

  11. Impact of caloric and dietary restriction regimens on markers of health and longevity in humans and animals: a summary of available findings

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    Kabir Mohammad M

    2011-10-01

    Full Text Available Abstract Considerable interest has been shown in the ability of caloric restriction (CR to improve multiple parameters of health and to extend lifespan. CR is the reduction of caloric intake - typically by 20 - 40% of ad libitum consumption - while maintaining adequate nutrient intake. Several alternatives to CR exist. CR combined with exercise (CE consists of both decreased caloric intake and increased caloric expenditure. Alternate-day fasting (ADF consists of two interchanging days; one day, subjects may consume food ad libitum (sometimes equaling twice the normal intake; on the other day, food is reduced or withheld altogether. Dietary restriction (DR - restriction of one or more components of intake (typically macronutrients with minimal to no reduction in total caloric intake - is another alternative to CR. Many religions incorporate one or more forms of food restriction. The following religious fasting periods are featured in this review: 1 Islamic Ramadan; 2 the three principal fasting periods of Greek Orthodox Christianity (Nativity, Lent, and the Assumption; and 3 the Biblical-based Daniel Fast. This review provides a summary of the current state of knowledge related to CR and DR. A specific section is provided that illustrates related work pertaining to religious forms of food restriction. Where available, studies involving both humans and animals are presented. The review includes suggestions for future research pertaining to the topics of discussion.

  12. Impact of caloric and dietary restriction regimens on markers of health and longevity in humans and animals: a summary of available findings.

    Science.gov (United States)

    Trepanowski, John F; Canale, Robert E; Marshall, Kate E; Kabir, Mohammad M; Bloomer, Richard J

    2011-10-07

    Considerable interest has been shown in the ability of caloric restriction (CR) to improve multiple parameters of health and to extend lifespan. CR is the reduction of caloric intake - typically by 20 - 40% of ad libitum consumption - while maintaining adequate nutrient intake. Several alternatives to CR exist. CR combined with exercise (CE) consists of both decreased caloric intake and increased caloric expenditure. Alternate-day fasting (ADF) consists of two interchanging days; one day, subjects may consume food ad libitum (sometimes equaling twice the normal intake); on the other day, food is reduced or withheld altogether. Dietary restriction (DR) - restriction of one or more components of intake (typically macronutrients) with minimal to no reduction in total caloric intake - is another alternative to CR. Many religions incorporate one or more forms of food restriction. The following religious fasting periods are featured in this review: 1) Islamic Ramadan; 2) the three principal fasting periods of Greek Orthodox Christianity (Nativity, Lent, and the Assumption); and 3) the Biblical-based Daniel Fast. This review provides a summary of the current state of knowledge related to CR and DR. A specific section is provided that illustrates related work pertaining to religious forms of food restriction. Where available, studies involving both humans and animals are presented. The review includes suggestions for future research pertaining to the topics of discussion.

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

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    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.

  14. Impact of caloric and dietary restriction regimens on markers of health and longevity in humans and animals: a summary of available findings

    Science.gov (United States)

    2011-01-01

    Considerable interest has been shown in the ability of caloric restriction (CR) to improve multiple parameters of health and to extend lifespan. CR is the reduction of caloric intake - typically by 20 - 40% of ad libitum consumption - while maintaining adequate nutrient intake. Several alternatives to CR exist. CR combined with exercise (CE) consists of both decreased caloric intake and increased caloric expenditure. Alternate-day fasting (ADF) consists of two interchanging days; one day, subjects may consume food ad libitum (sometimes equaling twice the normal intake); on the other day, food is reduced or withheld altogether. Dietary restriction (DR) - restriction of one or more components of intake (typically macronutrients) with minimal to no reduction in total caloric intake - is another alternative to CR. Many religions incorporate one or more forms of food restriction. The following religious fasting periods are featured in this review: 1) Islamic Ramadan; 2) the three principal fasting periods of Greek Orthodox Christianity (Nativity, Lent, and the Assumption); and 3) the Biblical-based Daniel Fast. This review provides a summary of the current state of knowledge related to CR and DR. A specific section is provided that illustrates related work pertaining to religious forms of food restriction. Where available, studies involving both humans and animals are presented. The review includes suggestions for future research pertaining to the topics of discussion. PMID:21981968

  15. Presentación clínica del golpe de calor en niños menores de 2 años en Lima - Perú

    Directory of Open Access Journals (Sweden)

    Reyner Loza Munarriz

    2001-10-01

    Full Text Available Objetivo: Describir el cuadro clínico de lactantes con golpe de calor (GC durante El Fenómeno de El Niño de 1998. Material y métodos: Se incluyeron 13 lactantes con criterios de GC, que acudieron a Emergencia Pediátrica del Hospital Cayetano Heredia entre el 1º de enero y el 31 de marzo de 1998. Se registró hematocrito, pruebas de coagulación, función hepática y renal, gasometría, electrolitos séricos y urinarios. Asimismo el flujo urinario, tipo de solución endovenosa utilizada para la rehidratación y la condición final del paciente al alta. Resultados: De los 13 lactantes, 4 fallecieron y 4 quedaron con secuelas neurológicas graves al alta. Los hallazgos clínicos relevantes fueron convulsiones (77%, dificultad respiratoria (85%, deshidratación (77%, shock (61%, diarrea aguda (85% y poliuria (75%. En el laboratorio general: anemia (84%, leucocitosis (60% tiempo de protrombina prolongado (53%, hiperglicemia (53% elevación de transaminasas (83%. En las alteraciones del medio interno; hiponatremia (84%, hipokalemia (70%, creatinina elevada (84%, urea elevada (53% y acidosis metabólica (100%. En el análisis sólo hubo asociación estadística entre el tiempo de protombina prolongado y el manejo inicial de fluidos con la condición final desfavorable. Conclusión: El GC es una enfermedad de pronóstico grave, donde el tiempo de protrombina prolongado, y el uso de soluciones hipertónicas en el manejo inicial, se asociaron a riesgo de muerte o secuelas neurológicas graves. Consideramos importante dar a conocer el comportamiento clínico y los factores asociados con un final catastrófico. (Rev Med Hered 2001; 12: 113-119.

  16. Alleviation of senescence and epithelial-mesenchymal transition in aging kidney by short-term caloric restriction and caloric restriction mimetics via modulation of AMPK/mTOR signaling.

    Science.gov (United States)

    Dong, Dan; Cai, Guang-Yan; Ning, Yi-Chun; Wang, Jing-Chao; Lv, Yang; Hong, Quan; Cui, Shao-Yuan; Fu, Bo; Guo, Ya-Nan; Chen, Xiang-Mei

    2017-03-07

    Renal fibrosis contributes to declining renal function in the elderly. What is unclear however, is whether epithelial-mesenchymal transition (EMT) contributes to this age-related renal fibrosis. Here, we analyzed indicators of EMT during kidney aging and investigated the protective effects and mechanisms of short-term regimens of caloric restriction (CR) or caloric restriction mimetics (CRMs), including resveratrol and metformin. High glucose was used to induce premature senescence and EMT in human primary proximal tubular cells (PTCs) in vitro. To test the role of AMPK-mTOR signaling, siRNA was used to deplete AMPK. Cellular senescence and AMPK-mTOR signaling markers associated with EMT were detected. CR or CRMs treatment alleviated age-related EMT in aging kidneys, which was accompanied by activation of AMPK-mTOR signaling. High glucose induced premature senescence and EMT in PTCs in vitro, which was accompanied by down-regulation of AMPK/mTOR signaling. CRMs alleviated high glucose-induced senescence and EMT via stimulation of AMPK/mTOR signaling. Activation of AMPK/mTOR signaling protected PTCs from high glucose-induced EMT and cellular senescence. Short-term regimens of CR and CRMs alleviated age-related EMT via AMPK-mTOR signaling, suggesting a potential approach to reducing renal fibrosis during aging.

  17. Recubrimiento de acero con polidopamina

    OpenAIRE

    Carrasco Rodríguez, Javier

    2013-01-01

    Se ha obtenido recubrimientos de polidopamina en acero mecánicamente resistentes y con tiempos de obtención relativamente pequeños a través de la polimerización de la dopamina bajo diferentes condiciones.

  18. Uso de transdutores de fluxo de calor no estudo da transferência de calor em alimentos embalados The use of heat flux transducers to study heat transfer in canned foods

    Directory of Open Access Journals (Sweden)

    B. Carciofi

    2002-12-01

    Full Text Available A densidade de fluxo de calor que atravessa uma superfície é classicamente determinada mediante a medição das temperaturas apropriadas e da aplicação da Lei de Fourier. Uma alternativa a esse procedimento é a utilização de transdutores de fluxo de calor, os quais geram um sinal elétrico proporcional ao fluxo térmico que os atravessa. Neste trabalho, processos de aquecimento e de resfriamento de alimentos foram estudados em laboratório, utilizando-se um recipiente de vidro cilíndrico para simular uma embalagem. Dois transdutores de fluxo de calor a gradiente tangencial foram previamente instalados no recipiente, revestindo completamente a superfície lateral do mesmo. O recipiente contendo a amostra foi inserido em banho de água circulante à temperatura constante. Os sinais fornecidos pelos transdutores e por termopares inseridos no interior do recipiente foram registrados por um sistema de aquisição de dados computadorizado. Os resultados obtidos com o uso dos transdutores foram comparados com aqueles obtidos através de balanços de energia realizados a partir dos dados experimentais de evolução temporal das temperaturas da amostra junto à superfície interna da embalagem e no centro da mesma. A comparação mostrou que os transdutores de fluxo de calor a gradiente tangencial puderam determinar os fluxos de calor, com tempo de resposta característico dos termopares. Os resultados apresentados mostraram a viabilidade de utilização desses fluxímetros no estudo não destrutivo e não invasivo dos processos de aquecimento e de resfriamento de alimentos, fornecendo informações complementares àquelas obtidas pelo uso de termopares instalados no interior da embalagem.Heat flux determination in thermal processes is classically carried out by appropriate temperature measurements and the application of the Fourier Law. An alternative to this procedure is to determine the heat flux that crosses a surface using heat flux

  19. MODELADO DE LAS ISOTERMAS DE SORCIÓN Y DEL CALOR ISOSTÉRICO DE SORCIÓN EN PULPA DE MANGO cv. TOMMY ATKINS MODELAGEM DE ISOTERMAS DE SORÇÃO E CALOR ISOSTÉRICO DE SORÇÃO DE POLPA DE MANGA cv. TOMMY ATKINS MODELING SORPTION ISOTHERMS AND ISOSTERIC HEAT OF SORPTION OF MANGO PULP cv. TOMMY ATKINS

    Directory of Open Access Journals (Sweden)

    JOSÉ BON

    2012-12-01

    Full Text Available El mango es un producto agrícola de gran importancia para diferentes países en vías de desarrollo, el cual ha incrementado su demanda por sus propiedades nutricionales y características exóticas. La relación entre el contenido de humedad y la actividad de agua suministra información útil para el procesamiento del mango, especialmente en las operaciones de secado y almacenamiento. La actividad de agua y el contenido de humedad de la pulpa de mango (Mangifera indica L. cv. Tommy Atkins fue analizada para determinar las isotermas de sorción. La actividad de agua fue medida utilizando un higrómetro eléctrico a cinco diferentes temperaturas (10, 20, 30, 40 y 50 °C y amplios rangos de contenido de humedad (2.829-0.031 kg kg-1 b.s. y actividad de agua (0.977-0.215. Un modelo teórico (GAB y cuatro ecuaciones empíricas (Oswin, Henderson, Halsey y Ratti fueron utilizados para representar las isotermas de sorción. Después de considerar diferentes criterios, el modelo de GAB fue evaluado como la mejor opción para representar el equilibrio higroscópico de la pulpa de mango (RMSE = 0.057, VAR = 0.996. Las isotermas mostraron un comportamiento acorde a los materiales agroalimentarios y similar al reportado para pulpa de mango de otras variedades. El calor isostérico de sorción fue calculado utilizando la ecuación de Clausius-Clapeyron a partir del modelo de GAB. Se observó una disminución en el calor isostérico de sorción al aumentar el contenido de humedad de equilibrio, con gran efecto de la humedad a valores por debajo de 0.8 kg kg-1 (b.s..A manga é um produto agrícola em países de desenvolvimento econômico, com grande aceitação devido a suas propriedades nutricionais e características exóticas. A relação entre o conteúdo de umidade e atividade de água proporciona informação útil para o processamento do mango, especialmente nas operações de secagem e armazenamento. A atividade de água e o conteúdo de umidade da

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

    Science.gov (United States)

    Asmaro, Deyar; Liotti, Mario

    2014-01-01

    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. PMID:24434747

  1. 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.

  2. Effect of long-term caloric restriction on brain monoamines in aging male and female Fischer 344 rats.

    Science.gov (United States)

    Kolta, M G; Holson, R; Duffy, P; Hart, R W

    1989-05-01

    The present study examines the changes in central monoamines and their metabolites in aged male and female rats after long-term caloric restriction. Fischer 344 rats of both sexes (n = 5-10/group) were maintained on one of two dietary regimens: ad libitum NIH 31 diet or 60% by weight of the ad lib. intake (restricted), supplemented with vitamins and minerals. Animals received these diets from the age of 14 weeks until killed at 22.25 months of age. Caudate nucleus (CN), hypothalamus (HYPO), olfactory bulb (OB) and nucleus accumbens (NA) were assayed for content of norepinephrine (NE), dopamine (DA) and its metabolites (dihydroxyphenylacetic acid, DOPAC, and homovanillic acid, HVA) and serotonin (5-HT) and its metabolite 5-hydroxyindoleacetic acid (5-HIAA) using HPLC/EC. Relative to the ad lib. group, restricted rats of both sex showed significant decreases in NE content in CN, HYPO and OB. DA and 5-HT content were decreased significantly in the CN and HYPO. No significant changes were found in the levels of DA metabolites in all brain regions studied. While the 5-HIAA level was significantly reduced in the HYPO and NA of the female restricted rats, it was increased several-fold in the OB of the male restricted animals. These preliminary results suggest that long-term caloric restriction alters brain monoamine concentrations, an effect which may in turn modify the normal rate of aging.

  3. Formation of S-(carboxymethyl)-cysteine in rat liver mitochondrial proteins: effects of caloric and methionine restriction.

    Science.gov (United States)

    Naudí, Alba; Jové, Mariona; Cacabelos, Daniel; Ayala, Victoria; Cabre, Rosanna; Caro, Pilar; Gomez, José; Portero-Otín, Manuel; Barja, Gustavo; Pamplona, Reinald

    2013-02-01

    Maillard reaction contributes to the chemical modification and cross-linking of proteins. This process plays a significant role in the aging process and determination of animal longevity. Oxidative conditions promote the Maillard reaction. Mitochondria are the primary site of oxidants due to the reactive molecular species production. Mitochondrial proteome cysteine residues are targets of oxidative attack due to their specific chemistry and localization. Their chemical, non-enzymatic modification leads to dysfunctional proteins, which entail cellular senescence and organismal aging. Previous studies have consistently shown that caloric and methionine restrictions, nutritional interventions that increase longevity, decrease the rate of mitochondrial oxidant production and the physiological steady-state levels of markers of oxidative damage to macromolecules. In this scenario, we have detected S-(carboxymethyl)-cysteine (CMC) as a new irreversible chemical modification in mitochondrial proteins. CMC content in mitochondrial proteins significantly correlated with that of the lysine-derived analog N (ε)-(carboxymethyl)-lysine. The concentration of CMC is, however, one order of magnitude lower compared with CML likely due in part to the lower content of cysteine with respect to lysine of the mitochondrial proteome. CMC concentrations decreases in liver mitochondrial proteins of rats subjected to 8.5 and 25 % caloric restriction, as well as in 40 and 80 % methionine restriction. This is associated with a concomitant and significant increase in the protein content of sulfhydryl groups. Data presented here evidence that CMC, a marker of Cys-AGE formation, could be candidate as a biomarker of mitochondrial damage during aging.

  4. Effect of caloric restriction with or without n-3 polyunsaturated fatty acids on insulin sensitivity in obese subjects: A randomized placebo controlled trial.

    Science.gov (United States)

    Razny, Urszula; Kiec-Wilk, Beata; Polus, Anna; Goralska, Joanna; Malczewska-Malec, Malgorzata; Wnek, Dominika; Zdzienicka, Anna; Gruca, Anna; Childs, Caroline E; Kapusta, Maria; Slowinska-Solnica, Krystyna; Calder, Philip C; Dembinska-Kiec, Aldona

    2015-12-01

    Caloric restriction and n-3 polyunsaturated fatty acid (PUFA) supplementation protect from some of the metabolic complications. The aim of this study was to assess the influence of a low calorie diet with or without n-3 PUFA supplementation on glucose dependent insulinotropic polypeptide (GIP) output and insulin sensitivity markers in obese subjects. Obese, non-diabetic subjects (BMI 30-40 kg/m(2)) and aged 25-65 yr. were put on low calorie diet (1200-1500 kcal/day) supplemented with either 1.8 g/day n-3 PUFA (DHA/EPA, 5:1) (n = 24) or placebo capsules (n = 24) for three months in a randomized placebo controlled trial. Insulin resistance markers and GIP levels were analysed from samples obtained at fasting and during an oral glucose tolerance test (OGTT). Caloric restriction with n-3 PUFA led to a decrease of insulin resistance index (HOMA-IR) and a significant reduction of insulin output as well as decreased GIP secretion during the OGTT. These effects were not seen with caloric restriction alone. Changes in GIP output were inversely associated with changes in red blood cell EPA content whereas fasting GIP level positively correlated with HOMA-IR index. Blood triglyceride level was lowered by caloric restriction with a greater effect when n-3 PUFA were included and correlated positively with fasting GIP level. Three months of caloric restriction with DHA + EPA supplementation exerts beneficial effects on insulin resistance, GIP and triglycerides. Combining caloric restriction and n-3 PUFA improves insulin sensitivity, which may be related to a decrease of GIP levels.

  5. The type of caloric sweetener added to water influences weight gain, fat mass, and reproduction in growing Sprague-Dawley female rats.

    Science.gov (United States)

    Light, Heather R; Tsanzi, Embedzayi; Gigliotti, Joseph; Morgan, Keri; Tou, Janet C

    2009-06-01

    Caloric sweetened beverages have been suggested to be a major dietary contributor to weight gain, particularly among adolescents. Dietary recommendations are for moderating intakes of added sugars; however, the question remains whether certain types of sugars should be limited. The objective of this study was to determine the effect of drinking different caloric sweetened beverages on the development of adiposity, metabolic, and endocrine disorders. Young (age 28 days) female Sprague-Dawley rats (n = 8-9 rats/group) were randomly assigned to drink either deionized distilled water (ddH2O) or ddH2O sweetened with 13% (w/v) glucose, sucrose, fructose or high fructose corn syrup 55 (HFCS-55) for 8 weeks. Rats drinking caloric sweetened solutions failed to completely compensate for liquid calories ingested by reducing their consumption of solid food. This resulted in greater total energy intake compared to the ddH2O control; however, there was no significant difference in total energy intake between rats drinking sucrose, fructose or HFCS-55. Of the different caloric sweeteners, only rats drinking HFCS-55 had greater (P glucose solution. This may have occurred because drinking HFCS-55 solution promoted a faster body weight gain. Adiposity induced by caloric sweetened water was not accompanied by metabolic disorders indicated by the absence of dyslipidemia and no differences in fasting serum glucose, insulin or C-peptide among the treatment groups. However, rats drinking HFCS-55 showed lengthened estrous cycles due to prolonged estrus. Based on this study, the type of caloric sweetener added to beverages should be considered when making dietary recommendation for reducing excess body weight and related health risk.

  6. Medida de calor específico e lei de resfriamento de Newton: um refinamento na análise dos dados experimentais

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    Silva Wilton Pereira da

    2003-01-01

    Full Text Available Uma das técnicas para a determinação do calor específico de sólidos e líquidos dispensa o uso de um calorímetro e utiliza a lei de resfriamento de Newton na análise dos dados experimentais. O sucesso desta técnica pressupõe que seja possível determinar, com pequenas incertezas, as temperaturas do sistema imediatamente antes e imediatamente depois das transferências internas de calor devido à imersão do corpo (dujo calor específico se deseja medir em um recipiente contendo água quente. Neste artigo é proposto um refinamento desta técnica utilizando-se dois ajustes de curvas para a função que descreve a lei de resfriamento, com pequenas extrapolações, para de determinar essas temperaturas e também as suas incertezas. Isto possibilita determinar não só o valor médio do calor específico, mas também a incerteza deste valor médio, por propagação de erros. O ajuste da própria função que descreve a lei de resfriamento aos dados possibilitou a comparação imediata dos parâmetros obtidos experimentalmente com aqueles previstos pela teoria, e há uma grande concerdânciaentre eles. A aplicaçãodeste refinamento na determinação do calor específico do alumínio indica que tal procedimento é eficaz mesmo quando se trabalha com instrumentos de baixo custo, voltados para o ensino.

  7. Effect of Short-term Quercetin, Caloric Restriction and Combined Treatment on Age-related Oxidative Stress Markers in the Rat Cerebral Cortex

    Science.gov (United States)

    Alugoju, Phaniendra; Swamy, Vkd Krishan; Periyasamy, Latha

    2018-03-14

    Aging is characterized by gradual accumulation of macromolecular damage leading to progressive loss of physiological function and increased susceptibility to diverse diseases. Effective anti-aging strategies involving caloric restriction or antioxidant supplementation are receiving growing attention to attenuate macromolecular damage in age associated pathology. In the present study, we for the first time investigated the effect of quercetin, caloric restriction and combined treatment (caloric restriction with quercetin) on oxidative stress parameters, acetylcholinesterase and ATPases enzyme activities in the cerebral cortex of aged male Wistar rats. 21 months aged rats were divided into four groups (n=6-8) such as group 1-fed ad libitum (AL); group 2-quercetin supplementation of 50 mg/kg b.w/day for 45 days fed ad libitum (QUER); group 3: caloric restricted (CR) (fed 40% reduced AL for 45 days); group 4-fed 40% CR and 50 mg/kg b.w/day QUER for 45 days (CR + QUER). Group 5-three month age old rats served as young control (YOUNG). Our results demonstrate that combined treatment of caloric restriction and quercetin significantly improved the age associated decline in the activities of endogenous antioxidant enzymes [such as superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)] and glutathione (GSH) content and attenuated elevated levels of protein carbonyl content (PCC), lipid peroxidation, lipofuscin, reactive oxygen species (ROS), and nitric oxide (NO). Furthermore, it is also observed that combined treatment ameliorated age associated alterations in acetylcholine esterase (AChE) and adenosine triphosphatases (ATPases) such as Na+/K+-ATPase and Ca+2-ATPase (but not Mg+2- ATPase) enzyme activities. Finally, we conclude that combined treatment of caloric restriction and quercetin (but not either treatment alone) in late life is an effective anti-aging therapy to counteract the age related accumulation of oxidative macromolecular damage

  8. Herdabilidade da necessidade de calor para a antese e brotação em pessegueiro Heritability of heat requirement for blooming and leafing in peach

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    Idemir Citadin

    2003-04-01

    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.Heritability of heat requirement for blooming and leafing was investigated in peach [Prunus persica (L. Batsch], using artificially chilled excised shoots of 11 populations and 16 parental clones of low, intermediate and high heat requirement. The estimated values of broad sense heritability of heat requirement in flower buds were 45% and 57%, in 1999 and 2000, respectively. In leaf buds, the heritability was 30% in 1999. 'BR-1', 'Barbosa', 'Chula', 'Chinoca', and 'Eldorado' can transmit the heat requirement character better to offspring than the others studied genotypes. The data support a model for quantitative inheritance with partial dominance for low heat requirement. Seedling selection for high heat requirement delay blooming more than leafing.

  9. Resveratrol and caloric restriction prevent hepatic steatosis by regulating SIRT1-autophagy pathway and alleviating endoplasmic reticulum stress in high-fat diet-fed rats.

    Science.gov (United States)

    Ding, Shibin; Jiang, Jinjin; Zhang, Guofu; Bu, Yongjun; Zhang, Guanghui; Zhao, Xiangmei

    2017-01-01

    Studies have demonstrated that resveratrol (a natural polyphenol) and caloric restriction activate Sirtuin-1 (SIRT1) and induce autophagy. Furthermore, autophagy is induced by the SIRT1-FoxO signaling pathway and was recently shown to be a critical protective mechanism against non-alcoholic fatty liver disease (NAFLD) development. We aimed to compare the effects of resveratrol and caloric restriction on hepatic lipid metabolism and elucidate the mechanism by which resveratrol supplementation and caloric restriction alleviate hepatosteatosis by examining the molecular interplay between SIRT1 and autophagy. Eight-week-old male Wistar rats (40) were divided into four groups: the STD group, which was fed a standard chow diet; the HFD group, which was fed a high-fat diet; HFD-RES group, which was fed a high-fat diet plus resveratrol (200 mg/kg.bw); and the HFD-CR group, which was fed a high-fat diet in portions containing 70% of the mean intake of the HFD group rats. The groups were maintained for 18 weeks. Metabolic parameters, Oil Red O and hematoxylin-eosin staining of the liver, and the mRNA and protein expression of SIRT1, autophagy markers and endoplasmic reticulum(ER) stress-associated genes in the liver were assessed after the 18-week treatment. We found that resveratrol (200 mg/kg bw) and caloric restriction (30%) partially prevented hepatic steatosis and hepatocyte ballooning, increased the expression of SIRT1 and autophagy markers while decreasing ER stress markers in the liver and alleviated lipid metabolism disorder. Moreover, caloric restriction provided superior protection against HFD-induced hepatic fatty accumulation compared with resveratrol and the effects were associated with decreased total energy intake and body weight. We conclude that the SIRT1-autophagy pathway and decreased ER stress are universally required for the protective effects of moderate caloric restriction (30%) and resveratrol (a pharmacological SIRT1 activator) supplementation

  10. Resveratrol and caloric restriction prevent hepatic steatosis by regulating SIRT1-autophagy pathway and alleviating endoplasmic reticulum stress in high-fat diet-fed rats.

    Directory of Open Access Journals (Sweden)

    Shibin Ding

    Full Text Available Studies have demonstrated that resveratrol (a natural polyphenol and caloric restriction activate Sirtuin-1 (SIRT1 and induce autophagy. Furthermore, autophagy is induced by the SIRT1-FoxO signaling pathway and was recently shown to be a critical protective mechanism against non-alcoholic fatty liver disease (NAFLD development. We aimed to compare the effects of resveratrol and caloric restriction on hepatic lipid metabolism and elucidate the mechanism by which resveratrol supplementation and caloric restriction alleviate hepatosteatosis by examining the molecular interplay between SIRT1 and autophagy.Eight-week-old male Wistar rats (40 were divided into four groups: the STD group, which was fed a standard chow diet; the HFD group, which was fed a high-fat diet; HFD-RES group, which was fed a high-fat diet plus resveratrol (200 mg/kg.bw; and the HFD-CR group, which was fed a high-fat diet in portions containing 70% of the mean intake of the HFD group rats. The groups were maintained for 18 weeks. Metabolic parameters, Oil Red O and hematoxylin-eosin staining of the liver, and the mRNA and protein expression of SIRT1, autophagy markers and endoplasmic reticulum(ER stress-associated genes in the liver were assessed after the 18-week treatment. We found that resveratrol (200 mg/kg bw and caloric restriction (30% partially prevented hepatic steatosis and hepatocyte ballooning, increased the expression of SIRT1 and autophagy markers while decreasing ER stress markers in the liver and alleviated lipid metabolism disorder. Moreover, caloric restriction provided superior protection against HFD-induced hepatic fatty accumulation compared with resveratrol and the effects were associated with decreased total energy intake and body weight.We conclude that the SIRT1-autophagy pathway and decreased ER stress are universally required for the protective effects of moderate caloric restriction (30% and resveratrol (a pharmacological SIRT1 activator

  11. Santiago, una ciudad con temor

    Directory of Open Access Journals (Sweden)

    Enrique Oviedo S.

    1999-04-01

    Full Text Available El objetivo general de este artículo es evaluar los efectos de la inseguridad ciudadana en el uso del espacio público. Dicha evaluación exige analizar dos relaciones que se establecen en el ámbito de la violencia: la relación entre victimización y percepción de inseguridad; y la que se establece entre actitudes sociales y resolución pacífica de conflictos nacionales. Para ello, se analizaron las variables victimización, percepción de inseguridad, uso del espacio físico, actitudes hacia el sistema institucional político y social y hacia la resolución de conflictos nacionales, y las posibles relaciones entre ellas. Los datos para realizar el estudio se obtuvieron por medio de una encuesta que se llevó a cabo con 1 200 personas de 18 y 70 años de edad residentes en la ciudad de Santiago. Los resultados indican que Santiago es una ciudad de habitantes con temor y que el aumento de la percepción de inseguridad de sus habitantes contrasta con el hecho de que las tasas de victimización se hayan mantenido, más o menos, constantes en los años que precedieron a la encuesta. El temor se relaciona con el abandono del espacio público físico y sociopolítico, así como con el refugio en los espacios y la vida privados. La actitud de resolver los conflictos por medios no pacíficos es frecuente y se asocia en mayor medida con la inseguridad, la actitud negativa hacia la democracia y la falta de expectativas sobre el futuro del país. Los resultados de este estudio respaldan la idea de que para superar el temor la gente tiende a adaptarse a la realidad adoptando una postura conformista, homogeneizando las creencias y los comportamientos, y sobreestimando la fuerza como medio para resolver las diferencias.

  12. Santiago, una ciudad con temor

    Directory of Open Access Journals (Sweden)

    Oviedo S. Enrique

    1999-01-01

    Full Text Available El objetivo general de este artículo es evaluar los efectos de la inseguridad ciudadana en el uso del espacio público. Dicha evaluación exige analizar dos relaciones que se establecen en el ámbito de la violencia: la relación entre victimización y percepción de inseguridad; y la que se establece entre actitudes sociales y resolución pacífica de conflictos nacionales. Para ello, se analizaron las variables victimización, percepción de inseguridad, uso del espacio físico, actitudes hacia el sistema institucional político y social y hacia la resolución de conflictos nacionales, y las posibles relaciones entre ellas. Los datos para realizar el estudio se obtuvieron por medio de una encuesta que se llevó a cabo con 1 200 personas de 18 y 70 años de edad residentes en la ciudad de Santiago. Los resultados indican que Santiago es una ciudad de habitantes con temor y que el aumento de la percepción de inseguridad de sus habitantes contrasta con el hecho de que las tasas de victimización se hayan mantenido, más o menos, constantes en los años que precedieron a la encuesta. El temor se relaciona con el abandono del espacio público físico y sociopolítico, así como con el refugio en los espacios y la vida privados. La actitud de resolver los conflictos por medios no pacíficos es frecuente y se asocia en mayor medida con la inseguridad, la actitud negativa hacia la democracia y la falta de expectativas sobre el futuro del país. Los resultados de este estudio respaldan la idea de que para superar el temor la gente tiende a adaptarse a la realidad adoptando una postura conformista, homogeneizando las creencias y los comportamientos, y sobreestimando la fuerza como medio para resolver las diferencias.

  13. 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.

  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)

    1997-12-31

    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. Comparison of Intermittent Fasting Versus Caloric Restriction in Obese Subjects: A Two Year Follow-Up.

    Science.gov (United States)

    Aksungar, F B; Sarıkaya, M; Coskun, A; Serteser, M; Unsal, I

    2017-01-01

    Caloric restriction (CR) is proven to be effective in increasing life span and it is well known that, nutritional habits, sleeping pattern and meal frequency have profound effects on human health. In Ramadan some Muslims fast during the day-light hours for a month, providing us a unique model of intermittent fasting (IF) in humans. In the present study, we have investigated the effects of IF versus CR on the same non-diabetic obese subjects who were followed for two years according to the growth hormone (GH)/Insulin like growth factor (IGF)-1 axis and insulin resistance. Single-arm Interventional Human Study. 23 female subjects (Body Mass Index (BMI) 29-39, aged between 28-42years). Follow-up is designed as 12 months of CR, after which there was a month of IF and 11 months of CR again, to be totally 24 months. Subjects' daily diets were aligned as low calorie diet during CR and during the IF period, the same subjects fasted for 15 hours in a day for a month and there was no daily calorie restriction. Nutritional pattern was changed as 1 meal in the evening and a late supper before sleeping and no eating and drinking during the day light hours in the IF model. Subjects made brisk walking twice a day during the whole follow-up including both CR and IF periods. BMI, Blood glucose, insulin, TSH, GH, HbA1c, IGF-1, Homa-IR and urinary acetoacetate levels were monitored once in three months and twice in the fasting month. While subjects lost 1250 ± 372g monthly during the CR, in the IF period, weight loss was decreased to 473 ± 146 g. BMI of all subjects decreased gradually and as the BMI decreased, glucose, HbA1c, insulin, Homa-IR and TSH levels were decreased. GH levels were at baseline at the beginning, increased in the first six months and stayed steady during the CR and IF period than began decreasing after the IF period, while IGF-I increased gradually during the CR period and beginning with the 7th day of IF period, it decreased and kept on decreasing till the

  17. Restricted versus continued standard caloric intake during the management of refeeding syndrome in critically ill adults: a randomised, parallel-group, multicentre, single-blind controlled trial.

    Science.gov (United States)

    Doig, Gordon S; Simpson, Fiona; Heighes, Philippa T; Bellomo, Rinaldo; Chesher, Douglas; Caterson, Ian D; Reade, Michael C; Harrigan, Peter W J

    2015-12-01

    Equipoise exists regarding the benefits of restricting caloric intake during electrolyte replacement for refeeding syndrome, with half of intensive care specialists choosing to continue normal caloric intake. We aimed to assess whether energy restriction affects the duration of critical illness, and other measures of morbidity, compared with standard care. We did a randomised, multicentre, single-blind clinical trial in 13 hospital intensive care units (ICUs) in Australia (11 sites) and New Zealand (two sites). Adult critically ill patients who developed refeeding syndrome within 72 h of commencing nutritional support in the ICU were enrolled and allocated to receive continued standard nutritional support or protocolised caloric restriction. 1:1 computer-based randomisation was done in blocks of variable size, stratified by enrolment serum phosphate concentration (>0·32 mmol/L vs ≤0·32 mmol/L) and body-mass index (BMI; >18 kg/m(2)vs ≤18 kg/m(2)). The primary outcome was the number of days alive after ICU discharge, with 60 day follow-up, in a modified intention-to-treat population of all randomly allocated patients except those mistakenly enrolled. Days alive after ICU discharge was a composite outcome based on ICU length of stay, overall survival time, and mortality. The Refeeding Syndrome Trial was registered with the Australian and New Zealand Clinical Trials Registry (ANZCTR number 12609001043224). Between Dec 3, 2010, and Aug 13, 2014, we enrolled 339 adult critically ill patients: 170 were randomly allocated to continued standard nutritional support and 169 to protocolised caloric restriction. During the 60 day follow-up, the mean number of days alive after ICU discharge in 165 assessable patients in the standard care group was 39·9 (95% CI 36·4-43·7) compared with 44·8 (95% CI 40·9-49·1) in 166 assessable patients in the caloric restriction group (difference 4·9 days, 95% CI -2·3 to 13·6, p=0·19). Nevertheless, protocolised caloric

  18. Solución de problemas inversos en conducción de calor mediante el método de simulación por redes

    OpenAIRE

    Zueco Jordán, Joaquín

    2009-01-01

    En la presente tesis doctoral se resuelven diferentes problemas inversos en conducción del calor mediante una serie de protocolos de resolución desarrollados y partiendo de medidas de temperaturas efectuadas en diferentes puntos del medio. Se establecen, dentro del campo de la transmisión del calor, nuevos procedimientos de estimación de funciones (que pueden ser extendidos al problema de estimación de parámetros) basados en el uso de funciones continuas del tipo "lineal a tramos" (piece wise...

  19. Monitor portátil de signos vitales con un PDA

    OpenAIRE

    Rodríguez Salazar, Rita Beatriz

    2007-01-01

    El monitor portátil de signos vitales facilita el proceso de medición y lleva un registro organizado de los valores medidos. Los signos vitales que se contempla son la temperatura corporal, la presión arterial y la frecuencia cardiaca.Para la medición de estos signos vitales se utilizan los sensores respectivos y se realiza el acondicionamiento de señal. Estas señales son procesadas en un PDA en el que también se visualiza los valores obtenidos en la medición y se registra estos datos si el u...

  20. Piscifactoria: sistemas de acondicionamiento y filtración

    OpenAIRE

    González Tejeda, Guillermo

    2013-01-01

    El objetivo principal de este proyecto es el diseño de las instalaciones y los equipos necesarios para el correcto funcionamiento de una piscifactoría de trucha arcoíris de una producción total anual de 600 toneladas, divididas en 6 lotes de 100 toneladas cada uno. Departamento de Química Analítica Ingeniero Técnico Industrial, Especialidad en Química Industrial

  1. 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.

  2. 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

  3. 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

  4. 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

  5. Energía calorífica necesaria, durante la soldadura en servicio de tuberías para el transporte de petróleo Necessary calorific energy, during the in-service welding of pipelines for petroleum transport

    Directory of Open Access Journals (Sweden)

    Félix Ramos Morales

    2009-03-01

    Full Text Available En el presente artículo, empleando el análisis por elementos finitos, se estudió el comportamiento térmico durante la soldadura de reparación, en condiciones de servicio, de un tubo que transporta petróleo. Se obtuvieron ecuaciones de regresión que relacionan a la temperatura máxima en la superficie interna del tubo y al tiempo de enfriamiento desde 800 ºC hasta 500 ºC de un punto situado en la zona afectada por el calor (ZAC, parámetros que gobiernan la ocurrencia de perforaciones en la pared del tubo y agrietamiento en frío respectivamente, con el calor de entrada de la soldadura, la temperatura de precalentamiento y el coeficiente de transferencia de calor por convección, variables que definen el comportamiento térmico durante la ejecución del proceso de soldadura. Se probó la existencia de una zona en que se satisfacen simultáneamente las ecuaciones obtenidas, para diferentes combinaciones de las variables relacionadas. Se presentaron nomogramas con un importante valor práctico, desarrollados a partir de la solución de las ecuaciones obtenidas.The thermal behavior during in service repair welding of oil transportation pipes was studied by finite element analysis in the present paper. Regression equations that relate peak temperature at the inner surface of the pipe and cooling time between 800 and 500ºC in the heat affected zone to the welding heat input, preheat temperature, and convection heat transfer coefficient were obtained. The former parameters govern, respectively, the possibility of burn through and cold cracking, and the latter parameters define the thermal behavior during welding. The existence of conditions that simultaneously satisfy the obtained equations, for different combinations of related variables, was proved. Graphical representations of relevant practical importance that were developed from the solution of obtained equations are presented.

  6. Evaluación integral de la sensibilidad en los pies de las personas con diabetes mellitus tipo 2

    Directory of Open Access Journals (Sweden)

    Valentina Rivas Acuña

    2017-01-01

    Full Text Available Introducción: Actualmente la diabetes mellitus tipo 2 es considerada una epidemia en el mundo, es uno de los problemas de mayor trascendencia, por su alta prevalencia como por su enorme repercusión social y económica, por tal motivo el propósito del estudio fue evaluar de manera integral la sensibilidad en los pies de las personas con diabetes mellitus tipo 2, de Villahermosa, Tabasco, México. Materiales y Métodos: El diseño fue descriptivo correlacional, la muestra fue de 198 personas. Se utilizó el Test del Michigan Neuropathy Screening con monofilamento de Semme Weinstein, Diapasón, temperatura frío/calor y reflejo Aquileo. Resultados y Discusión: El sexo femenino predominó con un 70.2% y el 29.8% hombres, el promedio de edad fue 56.44 años y 12.34 años promedio con la enfermedad. El 46% registró síntomas neuropáticos moderados, 26.3% graves; el 65.7% riesgo de neuropatía positiva (40.9% mujeres y 24.8% hombres, 41.1% con pérdida de sensibilidad moderada y 29.3% sensibilidad normal; el 74.7% tiene un control glucémico deficiente. Los factores de riesgo detectados con mayor prevalencia fueron helomas, hiperqueratosis y deformidades. Conclusiones: Existe una correlación significativa entre la pérdida de la sensibilidad con los años con la enfermedad, con la hiperglucemia y síntomas de neuropatía, la pérdida de sensibilidad en mujeres es de moderada a grave y en los hombres la pérdida de la sensibilidad es moderada. Cómo citar este artículo: Rivas V, Mateo Y, García H, Martínez A, Magaña M, Carrillo R.  Evaluación integral de la sensibilidad en los pies de las personas con diabetes mellitus tipo 2. Rev Cuid. 2017; 8(1:1423-32. http://dx.doi.org/10.15649/cuidarte.v8i1.348

  7. 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.

    Science.gov (United States)

    Lv, Mengmeng; Zhu, Xingya; Wang, Hao; Wang, Feng; Guan, Wenxian

    2014-01-01

    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.

  8. 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.

  9. Effects of aerobic versus resistance exercise without caloric restriction on abdominal fat, intrahepatic lipid, and insulin sensitivity in obese adolescent boys: a randomized, controlled trial

    Science.gov (United States)

    The optimal exercise modality for reductions of abdominal obesity and risk factors for type 2 diabetes in youth is unknown. We examined the effects of aerobic exercise (AE) versus resistance exercise (RE) without caloric restriction on abdominal adiposity, ectopic fat, and insulin sensitivity and se...

  10. The influence of caloric deprivation and food composition on TSH, thyroid hormones and nuclear binding of T3 in mononuclear blood cells in obese women

    DEFF Research Database (Denmark)

    Matzen, L E; Kvetny, J

    1989-01-01

    In vivo changes in thyroid-stimulating hormone (TSH), thyroxin (T4), triiodothyronine (T3) and nuclear binding of T3 (NBT3) in mononuclear blood cells were studied in obese women during seven days of caloric deprivation (maximum 1,100 kcal/d). In seven women given a high protein diet (80% protein...

  11. Time-resolved lateral spin-caloric transport of optically generated spin packets in n-GaAs

    Science.gov (United States)

    Göbbels, Stefan; Güntherodt, Gernot; Beschoten, Bernd

    2018-05-01

    We report on lateral spin-caloric transport (LSCT) of electron spin packets which are optically generated by ps laser pulses in the non-magnetic semiconductor n-GaAs at K. LSCT is driven by a local temperature gradient induced by an additional cw heating laser. The spatio-temporal evolution of the spin packets is probed using time-resolved Faraday rotation. We demonstrate that the local temperature-gradient induced spin diffusion is solely driven by a non-equilibrium hot spin distribution, i.e. without involvement of phonon drag effects. Additional electric field-driven spin drift experiments are used to verify directly the validity of the non-classical Einstein relation for moderately doped semiconductors at low temperatures for near band-gap excitation.

  12. Humedad de equilibrio y calor latente de vaporización del ajonjolí. Sésamun indicum L.

    Directory of Open Access Journals (Sweden)

    Julio E. Ospina M.

    1995-01-01

    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. Uso de dados de Sensoriamento Remoto para identificação de ilhas de calor em Teresina - PI

    Directory of Open Access Journals (Sweden)

    Felipe Ferreira Monteiro

    2012-12-01

    Full Text Available As mudanças climáticas globais são uma das grandes preocupações da atualidade e em áreas urbanas o aumento de temperatura é o fenômeno mais percebido. O trabalho objetiva identificar ilhas de calor em bairros da zona leste de Teresina-PI utilizando dados do satélite Landsat-5, para o ano de 2010. Foi possível verificar a relação entre a densidade construída, o padrão de ocupação e a pouca cobertura vegetal com as áreas de maiores temperatura na área estudada. O estudo demonstrou a influência da urbanização no aumento da temperatura e a necessidade das áreas verdes para minimizar os efeitos das mudanças climáticas.

  14. 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

    BACKGROUND: An aim of weight loss is to reduce the risk of type 2 diabetes (T2D) in obese subjects. However, the relation with long-term glycemic improvement remains unknown. OBJECTIVE: We evaluated the changes in lipid composition during weight loss and their association with long-term glycemic...... 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......: In this study, we report a lipid signature of LCD success (for weight and glycemic outcome) in obese, nondiabetic patients. Lipid changes during an 8-wk LCD allowed us to predict insulin-resistant patients after 6 mo of weight maintenance. The determination of the lipid composition during an LCD enables...

  15. Fluxo de calor sensível em cultivo de feijão-caupi Sensible heat flux in cowpea

    Directory of Open Access Journals (Sweden)

    José R. de S Lima

    2011-10-01

    Full Text Available O presente trabalho objetivou comparar o fluxo de calor sensível obtido pelo método do balanço de energia-razão de Bowen (H_B e pelo método aerodinâmico (H_A, em uma área de 4 ha cultivada com feijão-caupi em Areia-PB (6º 58' 12" S e 35º 42' 15" O, 620 m. Foram coletados dados de saldo de radiação, fluxo de calor no solo, temperatura e umidade do solo, temperatura e umidade relativa do ar, velocidade do vento e precipitação pluvial, os quais eram lidos a cada minuto, e armazenados, em uma central de aquisição de dados, como médias a cada 30 min, com exceção da pluviometria, cujo valor foi totalizado no período. Obteve-se excelente concordância entre H_A e H_B, com um índice "d " de 0,980, um erro padrão (EP de 14,88 W m-2, e sem diferença significativa entre H_A e H_B, pelo teste t-Student. Deste modo, o método aerodinâmico pode ser usado em conjunto com medidas de saldo de radiação e de fluxo de calor no solo, para se estimar o fluxo de calor latente e, consequentemente, a evapotranspiração da cultura do feijão-caupi, para as condições edafoclimáticas do Brejo Paraibano.A study was performed to compare the bulk aerodynamic (H_A and Bowen ratio energy balance (H_B methods in the estimation of the sensible heat flux in a cowpea crop. Data of net radiation, soil heat flux, soil water content, soil temperature, air temperature, relative humidity, wind speed and rainfall were collected on 30-min time intervals in an area of 4 ha belonging to the municipality of Areia, PB (6º 58' 12" S e 35º 42' 15" W, 620 m. Results showed that there was a good agreement between H_A and H_B with an index "d" of 0.98 and standard error of estimate (SEE of 14.88 W m-2, no significant difference between H_A H_B, by the t-Student test. Thus, the bulk aerodynamic method can be used in conjunction with measurements of net radiation and soil heat flux to estimate the evapotranspiration of the cowpea under soil and climatic condition of

  16. Estudo comparativo do comportamento da costura em tecido que retarda a chama submetida ao calor e à chama

    OpenAIRE

    Sandra Monteiro de Albuquerque

    2013-01-01

    A necessária atenção que se dá à seleção do tecido base da vestimenta de proteção ao calor e ao fogo é, algumas vezes, negligenciada no momento da confecção do produto. Fatores como a terceirização do processo de costura pelas empresas e a inspeção de qualidade somente no seu final, podem dificultar tanto o acompanhamento do processo de confecção, quanto a observação das especificações das normas regulamentadoras, possibilitando produção de vestimentas ineficazes na sua função protetora. A in...

  17. 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.

  18. [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

  19. 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

  20. Conversando con...Momoyo Kaijima

    OpenAIRE

    Gómez Alonso, Carlos; Álvarez Isidro, Eva; Torres Barchino, Ana

    2017-01-01

    [ES] Momoyo Kaijima es profesora en la Facultad de Arte y Diseño de la Universidad de Tsukuba en la Prefectura de Ibaraki y profesora visitante en la ETH de Zürich, en Royal Academy of Fine Arts, en Rice School of Architecture y en Harvard GSD. A lo largo de los años, Atelier Bow Wow ha colaborado con Krešimir Rogina, arquitecto de Zagreb y socio de la firma internacional Penezic&Rogina, en la realización del Grožnjan International Summer School of Architecture, siendo Rogina el nexo indispen...

  1. Effects of caloric deprivation on thyroid hormone tissue uptake and generation of low-T3 syndrome

    International Nuclear Information System (INIS)

    van der Heyden, J.T.M.; Docter, R.; van Toor, H.; Wilson, J.H.P.; Hennemann, G.; Krenning, E.P.

    1986-01-01

    Changes in thyroid hormone metabolism in the low-3,5,3'-triiodothyronine (T 3 ) syndrome cannot be fully explained in all conditions by a decrease in 5'-deiodinase activity. Recent observations showed that in rat hepatocytes iodothyronines are taken up by an active transport mechanism. To investigate whether regulation, i.e., inhibition of active transmembraneous transport for iodothyronines in humans may contribute to the generation of the low-T 3 syndrome, tracer thyroxine (T 4 ) and T 3 kinetic studies were performed in 10 obese subjects before and after 7 days on a 240 kcal diet. Kinetics analyses were performed according to a three-pool model of distribution and metabolism for both T 4 and T 3 . For T 4 kinetics, during caloric deprivation serum total T 4 and plasma pool did not change and production rate and metabolic clearance rate (MCR) were significantly lower. Despite a significantly higher serum free T 4 , the mass transfer rate to the rapidly equilibrating pool (REP) and the slowly equilibrating pool (SEP) diminished significantly, leading to smaller tissue pools. For T 3 kinetics, both serum total T 3 , free T 3 , plasma pool, and production rate diminished significantly, while MCR remained unchanged. These changes cannot be fully explained by a similar decrease of serum free T 3 (only 25%), indicating a diminished transport efficiency for T 3 . In conclusion, during caloric restriction, transport of T 4 and T 3 into tissues is diminished, and this phenomenon is much more pronounced for T 4 transport per se may contribute to low-T 3 production and low-T 3 serum levels due to less substrate (i.e., T 4 ) availability in tissues

  2. 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. Copyright © 2015. Published by Elsevier B.V.

  3. Curcumin Mimics the Neurocognitive and Anti-Inflammatory Effects of Caloric Restriction in a Mouse Model of Midlife Obesity.

    Directory of Open Access Journals (Sweden)

    Marjana Rahman Sarker

    Full Text Available Dietary curcumin was studied for its potential to decrease adiposity and reverse obesity- associated cognitive impairment in a mouse model of midlife sedentary obesity. We hypothesized that curcumin intake, by decreasing adiposity, would improve cognitive function in a manner comparable to caloric restriction (CR, a weight loss regimen. 15-month-old male C57BL/6 mice were assigned in groups to receive the following dietary regimens for 12 weeks: (i a base diet (Ain93M fed ad libitum (AL, (ii the base diet restricted to 70% of ad libitum (CR or (iii the base diet containing curcumin fed AL (1000 mg/kg diet, CURAL. Blood markers of inflammation, interleukin 6 (IL-6 and C-reactive protein (CRP, as well as an indicator of redox stress (GSH: GSSG ratio, were determined at different time points during the treatments, and visceral and subcutaneous adipose tissue were measured upon completion of the experiment. After 8 weeks of dietary treatment, the mice were tested for spatial cognition (Morris water maze and cognitive flexibility (discriminated active avoidance. The CR group showed significant weight loss and reduced adiposity, whereas CURAL mice had stable weight throughout the experiment, consumed more food than the AL group, with no reduction of adiposity. However, both CR and CURAL groups took fewer trials than AL to reach criterion during the reversal sessions of the active avoidance task, suggesting an improvement in cognitive flexibility. The AL mice had higher levels of CRP compared to CURAL and CR, and GSH as well as the GSH: GSSG ratio were increased during curcumin intake, suggesting a reducing shift in the redox state. The results suggest that, independent of their effects on adiposity; dietary curcumin and caloric restriction have positive effects on frontal cortical functions that could be linked to anti-inflammatory or antioxidant actions.

  4. Acute effects of different diet compositions on skeletal muscle insulin signalling in obese individuals during caloric restriction

    Science.gov (United States)

    Wang, Cecilia C.L.; Adochio, Rebecca L.; Leitner, J. Wayne; Abeyta, Ian M.; Draznin, Boris; Cornier, Marc-Andre

    2012-01-01

    Objective The cellular effects of restricting fat versus carbohydrate during a low-calorie diet are unclear. The aim of this study was to examine acute effects of energy and macronutrient restriction on skeletal muscle insulin signalling in obesity. Materials/Methods Eighteen obese individuals without diabetes underwent euglycemic-hyperinsulinemic clamp and skeletal muscle biopsy after: (a) 5 days of eucaloric diet (30% fat, 50% carbohydrate), and (b) 5 days of a 30% calorie-restricted diet, either low fat/high carbohydrate (LF/HC: 20% fat, 60% carbohydrate) or high-fat/low carbohydrate (HF/LC: 50% fat, 30% carbohydrate). Results Weight, body composition, and insulin sensitivity were similar between groups after eucaloric diet. Weight loss was similar between groups after hypocaloric diet, 1.3 ± 1.3 kg (pdiet. Skeletal muscle of the LF/HC group had increased insulin-stimulated tyrosine phosphorylation of IRS-1, decreased insulin-stimulated Ser 307 phosphorylation of IRS-1, and increased IRS-1-associated phosphatidylinositol (PI)3-kinase activity. Conversely, insulin stimulation of tyrosine phosphorylated IRS-1 was absent and serine 307 phosphorylation of IRS-1 was increased on HF/LC, with blunting of IRS-1-associated PI3-kinase activity. Conclusion Acute caloric restriction with a LF/HC diet alters skeletal muscle insulin signalling in a way that improves insulin sensitivity, while acute caloric restriction with a HF/LC diet induces changes compatible with insulin resistance. In both cases, ex vivo changes in skeletal muscle insulin signalling appear prior to changes in whole body insulin sensitivity. PMID:23174405

  5. Prefrontal cortex, caloric restriction and stress during aging: studies on dopamine and acetylcholine release, BDNF and working memory.

    Science.gov (United States)

    Del Arco, Alberto; Segovia, Gregorio; de Blas, Marta; Garrido, Pedro; Acuña-Castroviejo, Dario; Pamplona, Reinald; Mora, Francisco

    2011-01-01

    This study was designed to investigate whether long-term caloric restriction during the life span of the rat changes the effects of an acute mild stress on the release of dopamine and acetylcholine in the prefrontal cortex (PFC) and on working memory performance. Spontaneous motor activity was also monitored and levels of BDNF measured in the prefrontal cortex, amygdala and hippocampus. Male Wistar rats (3 months of age) were housed during 3, 12, 21 and 27 months (6, 15, 24 and 30 months of age at the end of housing) in caloric restriction (CR; 40% food intake restriction) or control conditions. After behavioural testing, animals were further subdivided into two other groups. In one of the groups BDNF protein levels were determined. In the other group rats were implanted with guide cannulas into the PFC to perform microdialysis experiments. In CR rats the release of dopamine produced by handling stress did not differ from the response found in control rats of 6, 15 and 24 months of age. The release of acetylcholine was not changed at the ages of 6 and 15 months but reduced at the age of 24 months. Stress did not change dopamine or acetylcholine release in CR and control rats of 30 months of age. BDNF levels were increased in the hippocampus and amygdala, but not in the PFC, of 6 and 15 months CR rats. Spontaneous motor activity was increased in all groups of CR rats. Age, however, decreased motor activity in CR and control rats. Both experimental groups showed similar working memory performance in a delayed alternation task in basal conditions and after a situation of acute stress. These results suggest that CR does not modify the function of the PFC in response to an acute stress nor the changes found as a result of the normal process of aging. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. Liquid meal composition, postprandial satiety hormones, and perceived appetite and satiety in obese women during acute caloric restriction.

    Science.gov (United States)

    Heden, Timothy D; Liu, Ying; Sims, Lauren; Kearney, Monica L; Whaley-Connell, Adam T; Chockalingam, Anand; Dellsperger, Kevin C; Fairchild, Timothy J; Kanaley, Jill A

    2013-04-01

    The purpose of this study was to compare postprandial satiety regulating hormone responses (pancreatic polypeptide (PP) and peptide tyrosine tyrosine (PYY)) and visual analog scale- (VAS) assessed perceived appetite and satiety between liquid high-protein (HP) and high-carbohydrate (HC) meals in obese women during acute (24-h) caloric restriction. Eleven obese premenopausal women completed two conditions in random order in which they consumed 1500 calories as six 250-calorie HP meals or six 250-calorie HC meals over a 12-h period. Blood samples were taken at baseline and every 20 min thereafter and analyzed for PP and PYY concentrations. At these same points, perceived hunger and fullness were assessed with a VAS. The incremental area under the curve (iAUC) was used to compare postprandial responses. The 12-h PP and PYY iAUC were greater (P≤0.05) during the HP condition (PP: 4727±1306 pg/ml×12 h, PYY: 1373±357 pg/ml×12 h) compared with the HC condition (PP: 2300±528 pg/ml×12 h, PYY: 754±246 pg/ml×12 h). Perceived hunger and fullness were not different between conditions (P>0.05). The greatest changes in PYY and perceived fullness occurred after the morning meals during both conditions. These data suggest that in obese women during acute caloric restriction before weight loss, i) liquid HP meals, compared with HC meals, result in greater postprandial PP and PYY concentrations, an effect not associated with differential appetite or satiety responses, and ii) meal-induced changes in PYY and satiety are greatest during the morning period, regardless of dietary macronutrient composition.

  7. Effects of caloric intake timing on insulin resistance and hyperandrogenism in lean women with polycystic ovary syndrome.

    Science.gov (United States)

    Jakubowicz, Daniela; Barnea, Maayan; Wainstein, Julio; Froy, Oren

    2013-11-01

    In women with PCOS (polycystic ovary syndrome), hyperinsulinaemia stimulates ovarian cytochrome P450c17α activity that, in turn, stimulates ovarian androgen production. Our objective was to compare whether timed caloric intake differentially influences insulin resistance and hyperandrogenism in lean PCOS women. A total of 60 lean PCOS women [BMI (body mass index), 23.7±0.2 kg/m²] were randomized into two isocaloric (~1800 kcal; where 1 kcal≈4.184 J) maintenance diets with different meal timing distribution: a BF (breakfast diet) (980 kcal breakfast, 640 kcal lunch and 190 kcal dinner) or a D (dinner diet) group (190 kcal breakfast, 640 kcal lunch and 980 kcal dinner) for 90 days. In the BF group, a significant decrease was observed in both AUC(glucose) (glucose area under the curve) and AUC(insulin) (insulin area under the curve) by 7 and 54% respectively. In the BF group, free testosterone decreased by 50% and SHBG (sex hormone-binding globulin) increased by 105%. GnRH (gonadotropin-releasing hormone)-stimulated peak serum 17OHP (17α-hydroxyprogesterone) decreased by 39%. No change in these parameters was observed in the D group. In addition, women in the BF group had an increased ovulation rate. In lean PCOS women, a high caloric intake at breakfast with reduced intake at dinner results in improved insulin sensitivity indices and reduced cytochrome P450c17α activity, which ameliorates hyperandrogenism and improves ovulation rate. Meal timing and distribution should be considered as a therapeutic option for women with PCOS.

  8. Abundance, biomass and caloric content of Chukchi Sea bivalves and association with Pacific walrus (Odobenus rosmarus divergens) relative density and distribution in the northeastern Chukchi Sea

    Science.gov (United States)

    Young, Jordann K.; Black, Bryan A.; Clarke, Janet T.; Schonberg, Susan V.; Dunton, Kenneth H.

    2017-10-01

    The northeastern Chukchi Sea is a shallow subarctic shelf ecosystem that supports a substantial benthic infaunal community of which bivalves are a major component. We assessed the patterns in population abundance, biomass, and caloric content of ten dominant bivalve taxa in relation to the distribution of the upper trophic level consumer Pacific walrus (Odobenus rosmarus divergens). Bivalves were collected over four cruises in the northeastern Chukchi Sea (2009, 2010, 2012, 2013). Our samples were largely dominated by calorie-dense, deposit-feeding species, including Macoma spp., Ennucula tenuis, Nuculana spp. and Yoldia spp. Weight-frequency distributions were strongly right-skewed for most taxa, though some showed evidence of a bimodal distribution. Caloric densities as measured through bomb calorimetry significantly differed among taxa (ANOVA F = 32.57, df = 9, p-valueanimal wet weight was found to be a reliable predictor of whole animal caloric content. Bivalve populations and peak caloric densities were centered on and to the southeast of Hanna Shoal, which coincided with peak Pacific walrus relative density (walruses per km surveyed) from July through October. Significant differences in mean caloric values were found between areas with and without walruses present (student's t-test, t=-2.9088, df = 252.24, p-value = 0.003952), as well as between areas with low and high walrus relative densities in the pooled annual dataset and in each individual month except October (ANOVA, p-value<0.05). The high-calorie deposit feeders that dominate these bivalve communities preferentially consume food sources, such as sea ice algae, that are likely to be affected by shifting sea ice dynamics. As such, continued warming has the potential to alter bivalve communities in the northeastern Chukchi Sea, which may have profound implications for upper trophic levels.

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

    Directory of Open Access Journals (Sweden)

    Cunha Antonio Ribeiro da

    2002-01-01

    Full Text Available 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 gradientes psicrométricos sobre a cultura. O cultivo protegido, apesar de receber menor quantidade de radiação solar global, foi mais eficiente na conversão da radiação líquida disponível em matéria seca total e na produtividade de frutos. No balanço de energia, o cultivo protegido apresentou razões G/Rn e LE/Rn inferiores e H/Rn superior, com um fluxo de calor latente, equivalente em milímetros, 45,43% menor que no cultivo no campo. Apresentou, ainda, menor quantidade de radiação líquida disponível e menores perdas de energia, mostrando-se mais eficiente no uso da água.

  10. Food irradiation - pros and cons

    International Nuclear Information System (INIS)

    1983-01-01

    The use of ionising radiation for food preservation is a much-disputed topic, both among experts and among consumers. Pros and cons of this issue were discussed in detail at the consumers' forum. Professor Dr. Johannes Friedrich Diehl, Director of the Institute for Biochemistry of the Food Research Centre, Karlsruhe, is a well-known supporter of the new method of food preservation; he sees advantages in the radiopreservation of food because, for example, losses due to inedibility are reduced, the danger of salmonellosis is decreased, just as the use of chemicals. He thinks this method to be without danger to health, shown by many years of experience. Opponents to food irradiation like Prof. Dr. Konrad Pfeilsticker, Professor for food science and food chemistry at the Bonn University deem the method to be unnecessary and raise the problem of qualitative changes caused in the food. In the course of the discussions, the pros and cons seemed to balance each other out. (orig./AJ) [de

  11. De paseo con los Bourbaki

    Directory of Open Access Journals (Sweden)

    Miquel Escudero

    2012-04-01

    Full Text Available Setenta y siete años después de la fundación del grupo Bourbaki, procedemos a una reflexión que puede ser útil para los estudiantes que acaso no sepan de su existencia, ni tan siquiera los de matemáticas. Sería interesante conocer que a este grupo se le debe el signo del vacío como conjunto. Con todo lo discutible que sea el método Bourbaki en su reinterpretación de la matemática, no cabe duda de su importante repercusión hasta el punto de que ha marcado una época. Hay un antes y un después tras su irrupción, ningún matemático de primera fila de la segunda mitad del siglo XX fue ajeno a su influjo, para encabezarlo o para reprobarlo. Comenzaron como una juvenil extravagancia, pero repleta de conocimientos y con decidida voluntad de aprehender el rigor de forma exhaustiva.

  12. Tratamiento del paciente con artrosis

    Directory of Open Access Journals (Sweden)

    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.

  13. Estudio del efecto térmico de espacios verdes urbanos del árido con sensores remotos

    Directory of Open Access Journals (Sweden)

    Alejandra Kurbán

    2015-12-01

    Full Text Available Se estudia el efecto térmico estacional de los espacios verdes urbanos en una ciudad de zona árida (San Juan, Argentina, a través del procesamiento de imágenes satelitales multiespectrales tipo LANDSAT 5 TM+ correspondientes al año 2011. La temperatura del aire se obtiene con el método TvX a partir de un muestreo amplio de relaciones entre el índice normalizado de vegetación NDVI y la temperatura de superficie. Los datos térmicos se combinan con registros de una estación meteorológica ubicada en el centro de la ciudad. Se cuantifican dichos datos y se relacionan con las bandas urbanas características de la ciudad y la isla de calor estacional, esta última obtenida del procesamiento de las mismas imágenes satelitales de 2011. Los resultados convalidan y amplían los conseguidos a partir de un previo trabajo de campo in situ, respecto al efecto bioclimático de los espacios verdes en sus ambientes urbanos áridos. Se verifica, finalmente, la eficiencia del uso de la teledetección para estudios urbanos, cuyos alcances puedan aplicarse al diseño urbano bioclimático.

  14. Cons ICARUS, TIGER and Fascism

    Directory of Open Access Journals (Sweden)

    Janez Vrečko

    2010-12-01

    Full Text Available Like the scientists of their time, Russian artists in the 1920s considered gravity the central problem – a view which points to the close harmony between modern physics and the avant-garde. It was only with the constructivist movement that the Icarus revolution grasped the principles of the “mobile philosophy” (3.651 which was almost at the same time recognised by modern physics as well. The static view of the world became obsolete, space and time were no longer absolute values. It was necessary to transcend Euclidean geometry, shake off the political ʻshackles on one’s hands’ and surrender to Lisicki’s imaginary space, where “At 2000 metres in the air / there is no more perspective” (Integrals 276.  Kosovel’s Icarus project accorded with Tatlin’s, and both of them accorded with the quintessential aims of the constructivist movement. It is no accident that Kosovel wished to name one of his poetry collections The Dream of Icarus. Poems on the Icarus theme, such as “Cons Icarus”, “Evacuation of the Spirit”, “Eh, Hey”, “A Heart in Alcohol” etc. belong to the group of Kosovel’s conses which follow his “mobile philosophy” (3.650 and “letters growing into space” (Int. 282.  The question “Man, do you want up in the air?” (Int. 128 will remain a question until the moment when man is finally ready to transcend the existing boundary and dive “beyond”. Hence Kosovel’s clear-cut contrast between the “green windows of an illuminated / express on a viaduct”, which moves horizontally and is, like a water current, subject to the earth’s gravity, and “the spirit in space”, whose direction of motion is “the perpendicular of the spirit”, atectonicity. “The spirit burns in space”: fire is an element that knows vertical movement alone, the only one of the elements to outgrow and transcend the earth’s gravity, therefore it is associated with another mythological figure important for

  15. 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.

  16. 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

  17. 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

  18. Depresion en pacientes con alteraciones del tiroides

    OpenAIRE

    Radanovic-Grguric´, Ljiljana; Filakovic´, Pavo; Barkic´, Jelena; Mandic´, Nikola; Karner, Ivan; Smoje, Juraj

    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...

  19. Aprende Ajedrez con Rey - Parte 2

    OpenAIRE

    ESTÉVEZ MONTERO, RAÚL; Lloret Mauri, Jaime

    2016-01-01

    Es una pieza audiovisual creada con el objeto de atraer la atención de los niños de muy corta edad con el ajedrez y familiarizarlos con todas sus piezas y movimientos. Es una animación dirigida a un público infantil presentada por dibujos animados en 2D, en la que se ha intentado respetar en todo momento el argot de la comunidad ajedredística. En este video se presenta la segunda parte. Estévez Montero, R.; Lloret Mauri, J. (2016). Aprende Ajedrez con Rey - Parte 2. http://hdl.handle.net/1...

  20. Aprende Ajedrez con Rey - Parte 1

    OpenAIRE

    ESTÉVEZ MONTERO, RAÚL; Lloret Mauri, Jaime

    2016-01-01

    Es una pieza audiovisual creada con el objeto de atraer la atención de los niños de muy corta edad con el ajedrez y familiarizarlos con todas sus piezas y movimientos. Es una animación dirigida a un público infantil presentada por dibujos animados en 2D, en la que se ha intentado respetar en todo momento el argot de la comunidad ajedredística. En este video se presenta la primera parte. Estévez Montero, R.; Lloret Mauri, J. (2016). Aprende Ajedrez con Rey - Parte 1. http://hdl.handle.net/1...

  1. 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.

  2. 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.

  3. Targeting tumor-initiating cells: Eliminating anabolic cancer stem cells with inhibitors of protein synthesis or by mimicking caloric restriction

    Science.gov (United States)

    Lamb, Rebecca; Harrison, Hannah; Smith, Duncan L.; Townsend, Paul A.; Jackson, Thomas; Ozsvari, Bela; Martinez-Outschoorn, Ubaldo E.; Pestell, Richard G.; Howell, Anthony; Lisanti, Michael P.; Sotgia, Federica

    2015-01-01

    We have used an unbiased proteomic profiling strategy to identify new potential therapeutic targets in tumor-initiating cells (TICs), a.k.a., cancer stem cells (CSCs). Towards this end, the proteomes of mammospheres from two breast cancer cell lines were directly compared to attached monolayer cells. This allowed us to identify proteins that were highly over-expressed in CSCs and/or progenitor cells. We focused on ribosomal proteins and protein folding chaperones, since they were markedly over-expressed in mammospheres. Overall, we identified >80 molecules specifically associated with protein synthesis that were commonly upregulated in mammospheres. Most of these proteins were also transcriptionally upregulated in human breast cancer cells in vivo, providing evidence for their potential clinical relevance. As such, increased mRNA translation could provide a novel mechanism for enhancing the proliferative clonal expansion of TICs. The proteomic findings were functionally validated using known inhibitors of protein synthesis, via three independent approaches. For example, puromycin (which mimics the structure of tRNAs and competitively inhibits protein synthesis) preferentially targeted CSCs in both mammospheres and monolayer cultures, and was ~10-fold more potent for eradicating TICs, than “bulk” cancer cells. In addition, rapamycin, which inhibits mTOR and hence protein synthesis, was very effective at reducing mammosphere formation, at nanomolar concentrations. Finally, mammosphere formation was also markedly inhibited by methionine restriction, which mimics the positive effects of caloric restriction in cultured cells. Remarkably, mammosphere formation was >18-fold more sensitive to methionine restriction and replacement, as directly compared to monolayer cell proliferation. Methionine is absolutely required for protein synthesis, since every protein sequence starts with a methionine residue. Thus, the proliferation and survival of CSCs is very sensitive to

  4. 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 Physiol 308: H894-H903, 2015). However, the exact mechanism by which Sirt1 in cardiomyocytes mediates the cardioprotective effect of CR remains undetermined. We subjected cardiomyocyte-specific Sirt1 knockout (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 conventional C3 knockout (C3(-/-)) mice treated with CR was similar to that in the ad libitum-fed C3(-/-)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

  5. 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

  6. Fasting during Ramadan and Associated Changes in Glycaemia, Caloric Intake and Body Composition with Gender Differences in Singapore.

    Science.gov (United States)

    Yeoh, Ester C K; Zainudin, Sueziani Binte; Loh, Win Nie; Chua, Chin Lian; Fun, Sharon; Subramaniam, Tavintharan; Sum, Chee Fang; Lim, Su Chi

    2015-06-01

    Millions of Muslim patients with diabetes mellitus (DM) fast during Ramadan. However, little is known about the metabolic impact of Ramadan fasting. We aimed to study the changes in body composition and metabolic profile in this group of patients. We studied 29 Southeast Asian Muslim patients with type 2 diabetes; all underwent pre-Ramadan education. Study variables were weight change, body composition (using multifrequency bioimpedance method, InBody S20®, Biospace, South Korea), blood pressure (BP), glycated haemoglobin (HbA1c), fasting lipid profile, and caloric intake assessment using FoodWorks® nutrient analysis software. Twenty-three subjects fasted ≥15 days; mean ± SD: 57 ± 11 years; 52% were males. HbA1c improved significantly (8.6 ± 2.4% pre-Ramadan vs 8.0 ± 2.3% end-Ramadan, P = 0.017). Despite similar body weight, there was reduction in body fat mass (BFM) (30.9 ± 11 kg vs 29.2 ± 12.2 kg, P = 0.013). Multivariate analysis suggested that the reduction in HbA1c was attributed by reduction in BFM (β = -0.196, P = 0.034). There was no change in visceral adiposity (visceral fat area (VFA)) but stratification by gender showed a reduction amongst females (137.6 ± 24.5 cm2 to 132.5 ± 25.7 cm2, P = 0.017). These changes occurred despite similar total caloric intake (1473.9 ± 565.4 kcal vs 1473.1 ± 460.4 kcal, P = 0.995), and proportion of carbohydrate (55.4 ± 6.3% vs 53.3 ± 7.5%, P = 0.25) and protein intake (17.6 ± 4.1% vs 17.3 ± 5.4%, P = 0.792), before and during Ramadan respectively, but with increased proportion of fat intake (11.9 ± 2.4% vs 13 ± 11.7%, P = 0.04). Seven out of 23 patients had medications adjusted to avert symptomatic hypoglycaemia but none of the patients developed severe hypoglycaemia. Ramadan fasting can be practiced safely with prior patient education and medication adjustment. It also confers modest benefits on metabolic profile and body composition, especially among females.

  7. 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.

  8. Plantas cubanas con efecto antiinflamatorio

    Directory of Open Access Journals (Sweden)

    Ada Ivis Regalado Veloz

    Full Text Available La actividad antiinflamatoria suscita gran interés científico en el área farmacológica, debido a que muchas enfermedades en su evolución cursan por procesos inflamatorios (artritis reumatoide, ateroesclerosis, cáncer, diabetes, gota, asma, dermatitis, trastornos neurodegenerativos y diversas dolencias menores. Las enfermedades inflamatorias constituyen un problema de salud importante, debido a la falta de medicamentos eficaces y seguros para su uso por periodos prolongados. Hoy en día se trabaja en la búsqueda de alternativas de antiinflamatorios más seguros, en el que las plantas medicinales, una de las formas más antiguas de tratamiento, constituyen una elección a considerar. En este trabajo se realizó una revisión bibliográfica, sobre especies de plantas que crecen en Cuba que le reportan propiedades farmacológicas como antinflamatorios. En la revisión de la literatura se utilizó la base de datos Medline (vía PubMed, así como revistas nacionales desde el periodo de 2000 hasta el presente, con las palabras claves "inflamación" y "plantas cubanas antiinflamatorias" o "actividad antiinflamatoria" y "plantas medicinales".

  9. Hospitalidad, con y sin papeles

    Directory of Open Access Journals (Sweden)

    Ana Paula Penchaszadeh

    Full Text Available Resumen El objetivo de este artículo es vincular el trabajo sobre el archivo de Jacques Derrida con la experiencia de la hospitalidad. Se intentará mostrar que, por un lado, se trata siempre de los papeles, de la legitimidad que éstos otorgan o no tanto a nivel filosófico (deseo de poseer los papeles que autoricen tal o cual decisión interpretativa, como a nivel político ("tener papeles" como el principio básico de todo derecho a tener derechos, de todo derecho a la comunidad. Mas también, por otro lado, se intentará pensar aquello que arruina la idea misma de tener o no tener (papeles, la idea de propiedad, aquello que hace imposible fundar una decisión o identidad en última instancia y, por ende, una soberanía, una frontera. La hospitalidad, la llegada inminente del otro, representa un desafío político y ético para la filosofía: pues no se trata de un saber, sino de una experiencia transformando el sustrato del nos-otros, del ser común.

  10. 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».

  11. CONTROL DE Anastrepha serpentina (Wiedemann Y CALIDAD DE LOS FRUTOS DE ZAPOTE MAMEY Pouteria sapota (Jacq Moore & Stearn TRATADOS CON AIRE CALIENTE FORZADO

    Directory of Open Access Journals (Sweden)

    R. Ariza-Flores

    2009-01-01

    Full Text Available Los objetivos de este estudio fue evaluar la efectividad de tratamientos térmicos con aire caliente forzado húmedo en el combate de la mosca de los zapotes (Anastrepha serpentina Wiedemann "in vivo" y determinar la tolerancia a las condiciones aplicadas de frutos de zapote mamey. Los frutos no fueron dañados internamente por el tratamiento térmico cuando fueron expuestos a 43 °C·120 min-1. Los frutos alcanzaron su madurez de consumo a los ocho días a 25 °C, presentaron cambios rápidamente en color y perdieron más peso; mientras que, a 10 °C se mantuvieron con mayor firmeza, prolongaron su vida de anaquel y mostraron mayores daños en los haces vasculares. Con respecto a la mortandad de los huevos y larvas de mosca de la fruta A. serpentina, éstas fueron del 100 % con la atmósfera controlada (CA de aire caliente a 43 °C·120 min-1, igualmente los frutos no fueron dañados por la aplicación de la CA; las larvas murieron fácilmente por el calor a 40 °C·120 min-1, mientras que los huevos fueron más resistentes ya que ocurrieron larvas emergidas a 25 °C para los ocho días de almacenados.

  12. The effect of alternate-day caloric restriction on the metabolic consequences of 8 days of bed rest in healthy lean men

    DEFF Research Database (Denmark)

    Harder-Lauridsen, Nina Majlund; Nielsen, Signe Tellerup; Mann, Sebastian Porsdam

    2017-01-01

    (control group, n = 10); and 2) 8 days of bed rest with 25% of total energy requirements every other day and 175% of total energy requirements every other day (ADCR group). Oral glucose tolerance testing, dual-energy X-ray absorptiometry (DXA) scans, magnetic resonance imaging of the abdomen and brain, V̇o......Physical activity and alternate-day fasting/caloric restriction may both ameliorate aspects of the metabolic syndrome, such as insulin resistance, visceral fat mass accumulation, and cognitive impairment by overlapping mechanisms. The purpose of this study was to test the hypothesis that alternate-day...... caloric restriction (ADCR) with overall energy balance would reduce insulin resistance and accumulation of visceral fat, in addition to improving cognitive functions, after 8 consecutive days in bed. Healthy, lean men (n = 20) were randomized to 1) 8 days of bed rest with three daily isoenergetic meals...

  13. 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

  14. Construcción de un calorímetro isoperibolico de inmersión de precisión

    Directory of Open Access Journals (Sweden)

    Liliana Giraldo G.

    2010-07-01

    Full Text Available Se diseña y construye un calorímetro isoperibólico tipo submarino para la medida de calores de inmersión de sólidos en líquidos. La celda calorimétrica, de una capacidad aproximada de 85 mi, se fabrica en vidrio Pyrex y va sumergida dentro de una chaqueta submarina construida en bronce cromado. El conjunto se introduce dentro de un termostato de agua estabilizado a 25 ±0,001 °C. El sensor de temperatura está constituido por termisiores NTC colocados en un puente de Maier transpuesto y provisto de una Fuente de intensidad constante. La sensibilidad del termómetro es del orden de 5 * I O' °C/p V cuando la corriente de medida en el puente es del orden de 1 mA.

  15. 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

  16. 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

  17. 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

  18. EXPRESIÓN SEMI-ANALÍTICA PARA EL CÁLCULO DE MATRICES DE CONDUCTIVIDAD DE ELEMENTOS FINITOS EN PROBLEMAS DE CONDUCCIÓN DE CALOR //\tA SEMI-ANALYTICAL EXPRESSION FOR CALCULATING FINITE ELEMENT CONDUCTIVITY MATRICES IN HEAT CONDUCTION PROBLEMS

    Directory of Open Access Journals (Sweden)

    Hector Godoy

    2012-12-01

    Full Text Available The heat transfer equation by conduction is not more than a mathematical expression of the energy conservation law for a given solid. Solving the equation which model this problem is generally very dificult or impossible in an analytical way, so it is necessary to make a discrete approximation of the continuous problem. In this paper, we present a methodology applied to the quadrilateral finite elements in problems of heat transfer by conduction, where the components of the thermal conductivity matrix are obtained by a semi-analytical expression and simple algebraic manipulations. This technique has been used successfully in stiness arrays' integrations of bidimensional and tridimensional finite elements, reporting substantial improvements of CPU times compared with the Gaussian integration. // RESUMEN: La ecuación para la transferencia de calor por conducción no es más que una expresión matemática de la ley de conservación de la energía para un sólido dado. La resolución de la ecuación que modela este problema generalmente es muy difícil o imposible de obtener de forma analítica, por ello es necesario efectuar una aproximación discreta del problema continuo. En este trabajo, se presenta una metodología aplicada a elementos finitos cuadriláteros en problemas de transferencia de calor por conducción, donde las componentes de la matriz de conductividad térmica son obtenidas mediante una expresión semi-analítica y manipulaciones algebraicas sencillas. Esta técnica ha sido utilizada exitosamente en integraciones de matrices de rigidez de elementos finitos bidimensionales y tridimensionales,reportando mejoras sustanciales de tiempos de CPU en comparación con la integración Gaussiana.

  19. Impact of Age, Caloric Restriction, and Influenza Infection on Mouse Gut Microbiome: An Exploratory Study of the Role of Age-Related Microbiome Changes on Influenza Responses

    OpenAIRE

    Jenna M. Bartley; Jenna M. Bartley; Xin Zhou; Xin Zhou; George A. Kuchel; George A. Kuchel; George M. Weinstock; George M. Weinstock; Laura Haynes; Laura Haynes

    2017-01-01

    Immunosenescence refers to age-related declines in the capacity to respond to infections such as influenza (flu). Caloric restriction represents a known strategy to slow many aging processes, including those involving the immune system. More recently, some changes in the microbiome have been described with aging, while the gut microbiome appears to influence responses to flu vaccination and infection. With these considerations in mind, we used a well-established mouse model of flu infection t...

  20. 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.

  1. Whey protein and essential amino acids promote the reduction of adipose tissue and increased muscle protein synthesis during caloric restriction-induced weight loss in elderly, obese individuals

    Directory of Open Access Journals (Sweden)

    Coker Robert H

    2012-12-01

    Full Text Available Abstract Background Excess adipose tissue and sarcopenia presents a multifaceted clinical challenge that promotes morbidity and mortality in the obese, elderly population. Unfortunately, the mortality risks of muscle loss may outweigh the potential benefits of weight loss in the elderly. We have previously demonstrated the effectiveness of whey protein and essential amino acids towards the preservation of lean tissue, even under the conditions of strict bedrest in the elderly. Methods In the context of caloric restriction-based weight loss, we hypothesized that a similar formulation given as a meal replacement (EAAMR would foster the retention of lean tissue through an increase in the skeletal muscle fractional synthesis rate (FSR. We also proposed that EAAMR would promote the preferential loss of adipose tissue through the increased energy cost of skeletal muscle FSR. We recruited and randomized 12 elderly individuals to an 8 week, caloric restriction diet utilizing equivalent caloric meal replacements (800 kcal/day: 1 EAAMR or a 2 competitive meal replacement (CMR in conjunction with 400 kcal of solid food that totaled 1200 kcal/day designed to induce 7% weight loss. Combined with weekly measurements of total body weight and body composition, we also measured the acute change in the skeletal muscle FSR to EAAMR and CMR. Results By design, both groups lost ~7% of total body weight. While EAAMR did not promote a significant preservation of lean tissue, the reduction in adipose tissue was greater in EAAMR compared to CMR. Interestingly, these results corresponded to an increase in the acute skeletal muscle protein FSR. Conclusion The provision of EAAMR during caloric restriction-induced weight loss promotes the preferential reduction of adipose tissue and the modest loss of lean tissue in the elderly population.

  2. Liraglutide suppression of caloric intake competes with the intake-promoting effects of a palatable cafeteria diet, but does not impact food or macronutrient selection.

    Science.gov (United States)

    Hyde, Kellie M; Blonde, Ginger D; le Roux, Carel W; Spector, Alan C

    2017-08-01

    Liraglutide, a Glucagon-Like Peptide-1 (GLP-1) receptor agonist, is used as a treatment for Type 2 diabetes mellitus and obesity because it improves glycemia and decreases food intake. Here, we tested whether chronic activation of the GLP-1 receptor system with liraglutide would induce decreases in intake accompanied by changes in proportional food or macronutrient intake similar to those seen following RYGB in rats when a variety of palatable food options are available. A "cafeteria diet" was used that included: laboratory rodent chow, refried beans (low-fat/low-sugar), low-fat yogurt (low-fat/high-sugar), peanut butter (high-fat/low-sugar) and sugar-fat whip (high-fat/high-sugar). Liraglutide (1mg/kg daily, sc, n=6) induced significant reductions in body weight and total caloric intake compared to saline-injected control rats (n=6). Although access to a cafeteria diet induced increases in caloric intake in both groups relative to chow alone, liraglutide still effectively decreased intake compared with saline-injected rats suggesting that chronic GLP-1 activation competes with the energy density and palatability of available food options in modulating ingestive behavior. Even with the substantial effects on overall intake, liraglutide did not change food choice or relative macronutrient intake when compared to pre-treatment baseline. When drug treatment was discontinued, the liraglutide group increased caloric intake and rapidly gained body weight to match that of the saline group. These results demonstrate that, while liraglutide effectively decreases caloric intake and body weight in rats, it does not cause adjustments in relative macronutrient consumption. Our data also show that drug-induced decreases in intake and body weight are not maintained following termination of treatment. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. 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.

  4. Bases tratadas con cemento, en California

    Directory of Open Access Journals (Sweden)

    Chinchilla, M.

    1962-05-01

    Full Text Available El uso de bases tratadas con cemento para autopistas se inició en el Estado de California en 1938, empleándose para carreteras con determinadas condiciones de tráfico. Inicialmente, se especificó el uso obligatorio de plantas mezcladoras para asegurar el debido control de las proporciones adecuadas.

  5. A randomized pilot study comparing zero-calorie alternate-day fasting to daily caloric restriction in adults with obesity.

    Science.gov (United States)

    Catenacci, Victoria A; Pan, Zhaoxing; Ostendorf, Danielle; Brannon, Sarah; Gozansky, Wendolyn S; Mattson, Mark P; Martin, Bronwen; MacLean, Paul S; Melanson, Edward L; Troy Donahoo, William

    2016-09-01

    To evaluate the safety and tolerability of alternate-day fasting (ADF) and to compare changes in weight, body composition, lipids, and insulin sensitivity index (Si) with those produced by a standard weight loss diet, moderate daily caloric restriction (CR). Adults with obesity (BMI ≥30 kg/m(2) , age 18-55) were randomized to either zero-calorie ADF (n = 14) or CR (-400 kcal/day, n = 12) for 8 weeks. Outcomes were measured at the end of the 8-week intervention and after 24 weeks of unsupervised follow-up. No adverse effects were attributed t