5,179 research outputs found

    The Einstein-Boltzmann Relation for Thermodynamic and Hydrodynamic Fluctuations

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    When making the connection between the thermodynamics of irreversible processes and the theory of stochastic processes through the fluctuation-dissipation theorem, it is necessary to invoke a postulate of the Einstein-Boltzmann type. For convective processes hydrodynamic fluctuations must be included, the velocity is a dynamical variable and although the entropy cannot depend directly on the velocity, ÎŽ2S\delta^{2} S will depend on velocity variations. Some authors do not include velocity variations in ÎŽ2S\delta^{2} S, and so have to introduce a non-thermodynamic function which replaces the entropy and does depend on the velocity. At first sight, it seems that the introduction of such a function requires a generalisation of the Einstein-Boltzmann relation to be invoked. We review the reason why it is not necessary to introduce such a function, and therefore why there is no need to generalise the Einstein-Boltzmann relation in this way. We then obtain the fluctuation-dissipation theorem which shows some differences as compared with the non-convective case. We also show that ÎŽ2S\delta^{2} S is a Liapunov function when it includes velocity fluctuations.Comment: 13 Page

    Factors that influence the process of formation of the olympic judokas

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    Con el objetivo de analizar los factores que influyen en el proceso de formación deportiva de los judokas españoles olímpicos, se aplicó una entrevista semiestructurada de 52 preguntas agrupadas en 6 dimensiones (Contexto Deportivo, Contexto Social, Proceso de Formación, Psicológica, Técnico-tåctica, Condición Física). Los resultados muestran que los judokas olímpicos se iniciaron en la pråctica del Judo a los 6,90 ± 3,02 años, concretamente las mujeres a los 6,80 ± 2,88 años y los hombres algo mås tarde, a los 7 ± 3,42 años, el 95% (n=19) influenciados, fundamentalmente, por un familiar. Ademås, destaca que ninguno de los entrevistados consiguió medalla en categorías inferiores. Para el 75% (n=15) de los judokas olímpicos es muy importante llevar una sincronización del entrenamiento técnico-tåctico, de la condición física y de los aspectos psicológicos de forma integradaWith the aim of analizing the factors that have an influence on the sports training process of the olympic Spanish judokas, a semistructured interview of 52 questions grouped in 6 aspects was carried out: Sports Context, Social Context, Training Process, Psychological Condition, Technical-Tactical Condition and Physical Conditon). The results show that olympic judokas began practising judo at the age of 6.90 ± 3.02 years. Specifically, women started at the age of 6.80 ± 2.88, and men slightly later, at the age of 7 ± 3.42 years. 95% (n=19) of them were mainly influenced by a relative. Moreover, it is to be highlighted that none of the interviewees won a medal in low categories. For 75% (n=15) of the olympic judokas, it is very important that technical-tactical training, physical condition training and psychological aspects be synchronised in an integrated wa

    Identidad taxonómica de algunos taxones del género endémico ibérico Iberus Montfort, 1810 (Gastropoda, Helicidae)

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    Se revisan las series tipo de las especies de Iberus descritas por RossmĂ€ssler (1854) y depositadas en el Senckenberg Forschungsinstitut und Naturmuseum de Frankfurt, Alemania. Se concluye que Helix alcarazana (actualmente Iberus alcarazanus) es sinĂłnimo posterior de Iberus alonensis (FĂ©russac, 1821). Se discuten y modifican las localidades tipo de Helix y de Helix alcarazana y se designan lectotipos para Helix guiraoana, Helix guiraoana var. angustata, Helix alcarazana y Helix loxana. AdemĂĄs, se revisa la serie tipo de Helix alonensis (FĂ©russac, 1821) (actualmente Iberus alonensis) depositada en el MusĂ©um national d’Histoire naturelle de ParĂ­s, Francia. Se selecciona el lectotipo y se designa “Alicante” como localidad tipo restringida.To determine the taxonomic identity of some of the species included in the genus Iberus, we reviewed the type series described by RossmĂ€ssler (1854) and deposited at the Senckenberg Forschungsinstitut und Naturmuseum of Frankfurt (Germany). We concluded that Helix alcarazana (currently Iberus alcarazanus) is a junior synonym of Iberus alonensis (FĂ©russac, 1821). The type localities of Helix guiraoana and Helix alcarazana were discussed and modified and the lectotypes of Helix guiraoana, Helix guiraoana var. angustata, Helix alcarazana and Helix loxana were designated. In addition, we reviewed the type series of Helix alonensis FĂ©russac, 1821 (currently Iberus alonensis) deposited at the MusĂ©um national d’Histoire naturelle of Paris, France and we selected its lectotype. The locality of Alicante has been designated as the restricted type locality of this species.Se revisan las series tipo de las especies de Iberus descritas por RossmĂ€ssler (1854) y depositadas en el Senckenberg Forschungsinstitut und Naturmuseum de Frankfurt, Alemania. Se concluye que Helix alcarazana (actualmente Iberus alcarazanus) es sinĂłnimo posterior de Iberus alonensis (FĂ©russac, 1821). Se discuten y modifican las localidades tipo de Helix y de Helix alcarazana y se designan lectotipos para Helix guiraoana, Helix guiraoana var. angustata, Helix alcarazana y Helix loxana. AdemĂĄs, se revisa la serie tipo de Helix alonensis (FĂ©russac, 1821) (actualmente Iberus alonensis) depositada en el MusĂ©um national d’Histoire naturelle de ParĂ­s, Francia. Se selecciona el lectotipo y se designa “Alicante” como localidad tipo restringida

    Decoherence in an accelerated universe

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    In this paper we study the decoherence processes of the semiclassical branches of an accelerated universe due to their interaction with a scalar field with given mass. We use a third quantization formalism to analyze the decoherence between two branches of a parent universe caused by their interaction with the vaccum fluctuations of the space-time, and with other parent unverses in a multiverse scenario.Comment: 11 pages, 2 figure

    A dark energy multiverse

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    We present cosmic solutions corresponding to universes filled with dark and phantom energy, all having a negative cosmological constant. All such solutions contain infinite singularities, successively and equally distributed along time, which can be either big bang/crunchs or big rips singularities. Classicaly these solutions can be regarded as associated with multiverse scenarios, being those corresponding to phantom energy that may describe the current accelerating universe

    Quantum state of the multiverse

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    A third quantization formalism is applied to a simplified multiverse scenario. A well defined quantum state of the multiverse is obtained which agrees with standard boundary condition proposals. These states are found to be squeezed, and related to accelerating universes: they share similar properties to those obtained previously by Grishchuk and Siderov. We also comment on related works that have criticized the third quantization approach.Comment: 15 pages, 2 figure

    PSS22 FINAL EVALUATION OF THE PERSISTENCE DEGREE OF PATIENTS IN FIRST-LINE MONOTHERAPY ANTIGLAUCOMATOUS TREATMENT IN SPAIN

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    Differences of the game between the football Spanish team and its rivals.

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    El objeto de este estudio, analizando la acción de juego en fútbol, describe el uso de los contextos de interacción que la selección española de fútbol y sus rivales hicieron en los campeonatos internacionales. Para ello, 13 partidos fueron observados y codificados (seis de la Eurocopa 2008 y siete del Mundial 2010) gracias a un sistema taxonómico ad hoc previamente definido. Los datos fueron registrados usando un software específico. Después, coordenadas polares fueron desarrolladas usando sólo como conductas criterio los contextos de interacción. Los resultados obtenidos describen que España y sus oponentes no hicieron el mismo uso del espacio de juego en sus partidos (más ofensivo para los primeros), mostrando la dimensión diacrónica de los eventos y combinando las perspectivas prospectiva y retrospectiva. Esto nos permite saber el componente estratégico del uso de los contextos de interacción hechos por los equipos en la competición y optimizar programas de entrenamiento específicos.Este estudio es parte del proyecto titulado Avances Tecnológicos y Metodológicos en la Automatización de Estudios observacionales en deporte, financiado por Dirección General de Investigación de España, Ministerio de Ciencia e Innovación (PSI2008-01179) en el período 2008-2011. No existen conflictos de intereses para esta investigación
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