2,466 research outputs found

    Enhanced Parallel Generation of Tree Structures for the Recognition of 3D Images

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    Segmentations of a digital object based on a connectivity criterion at n-xel or sub-n-xel level are useful tools in image topological analysis and recognition. Working with cell complex analogous of digital objects, an example of this kind of segmentation is that obtained from the combinatorial representation so called Homological Spanning Forest (HSF, for short) which, informally, classifies the cells of the complex as belonging to regions containing the maximal number of cells sharing the same homological (algebraic homology with coefficient in a field) information. We design here a parallel method for computing a HSF (using homology with coefficients in Z/2Z) of a 3D digital object. If this object is included in a 3D image of m1 × m2 × m3 voxels, its theoretical time complexity order is near O(log(m1 + m2 + m3)), under the assumption that a processing element is available for each voxel. A prototype implementation validating our results has been written and several synthetic, random and medical tridimensional images have been used for testing. The experiments allow us to assert that the number of iterations in which the homological information is found varies only to a small extent from the theoretical computational time.Ministerio de Economía y Competitividad MTM2016-81030-

    Accretion and photodesorption of CO ice as a function of the incident angle of deposition

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    Non-thermal desorption of inter- and circum-stellar ice mantles on dust grains, in particular ultraviolet photon-induced desorption, has gained importance in recent years. These processes may account for the observed gas phase abundances of molecules like CO toward cold interstellar clouds. Ice mantle growth results from gas molecules impinging on the dust from all directions and incidence angles. Nevertheless, the effect of the incident angle for deposition on ice photo-desorption rate has not been studied. This work explores the impact on the accretion and photodesorption rates of the incidence angle of CO gas molecules with the cold surface during deposition of a CO ice layer. Infrared spectroscopy monitored CO ice upon deposition at different angles, ultraviolet-irradiation, and subsequent warm-up. Vacuum-ultraviolet spectroscopy and a Ni-mesh measured the emission of the ultraviolet lamp. Molecules ejected from the ice to the gas during irradiation or warm-up were characterized by a quadrupole mass spectrometer. The photodesorption rate of CO ice deposited at 11 K and different incident angles was rather stable between 0 and 45^{\circ}. A maximum in the CO photodesorption rate appeared around 70^{\circ}-incidence deposition angle. The same deposition angle leads to the maximum surface area of water ice. Although this study of the surface area could not be performed for CO ice, the similar angle dependence in the photodesorption and the ice surface area suggests that they are closely related. Further evidence for a dependence of CO ice morphology on deposition angle is provided by thermal desorption of CO ice experiments

    Análisis de la solución sólida aragonito-estroncianita mediante espectroscopia vibracional (Infrarrojo y FT-Raman)

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    Depto. de Mineralogía y PetrologíaFac. de Ciencias GeológicasTRUEpu

    FT-Raman and infrared spectroscopic study of aragonite-strontianite (CaxSr1-xC03) solid solution

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    Synthetic aragonite-strontianite solid-solution samples have been studied using dispersive IR and FT-Raman spectroscopy. In addition to the end-members, nine samples over a range of composition from Ca0,9Sr0,1CO3 to Ca0,1Sr0,9CO3 were analysed. Carbonate anion internal modes are examined in detail by means of band-shape analysis and component fitting procedures. Positional disorder induced by the random cationic substitution results in strong increase of the halfwidth in several vibrational bands. Results obtained for the doubly degenerate modes (antisymmetric stretching and bending, v3 and v4) reveal the presence of three components both in the IR antisymmetric stretching band as well as in the Raman antisymmetric bending band. These observations are interpreted in terms of an overtone 2v4 in possible Fermi resonance with the corresponding vg fundamental in the IR spectra, and the presence of Davidov (factor group) splitting in the FT-Raman v4 band. Lattice modes in the FT-Raman spectra demonstrate weaker cohesion between the cation/carbonate/cation layers in aragonite (synth) than in strontianite (synth)

    Metrological intercomparison of six terrestrial laser scanning systems

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    6 p.Intercomparison among six terrestrial laser scanner systems focused on the measurement of small elements ( <; 0.5 m) is performed. Phase shift (PS) and time of flight (ToF) scanners are considered. Two standard artefacts containing three-dimensional printing spheres and steps of variable height are used for the experiment. Results show errors between -4.5 and 3.5 mm in the measurement of distances between step planes. The most stable systems for measuring small elements seem the Leica C10, Faro Photon and Riegl LMS Z390i. The quality of the results is linked to the overall quality of the system rather than the specific technology used for range measurement (PS or ToF) which does not appear to be a determining factor.S

    Source apportionment of ultrafine and fine particles in Huelva industrial city

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    Comunicación presentada en: 2012 European Aerosol Conference (EAC-2012), B-WG01S2P30, celebrada del 2 al 7 de septiembre de 2012 en Granada

    Bienestar psicológico, personalidad y actividad física. Un estilo de vida para la vida adulta

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    Practice of physical activity is increasingly important for people both as a recreational activity as a health activity. Although it is difficult to find human behaviors that do not have any influence on the health and well-being, it´s possible to show conduct that are among the most important risk factors of major health problems today such as consumption alcohol, obesity and snuff. Regular healthy physical exercise following programmes or frequent and regular autonomous activities improves mental health, autonomy, memory, speed, body image and the feeling of wellbeing, while producing personal stability characterised by optimism, emotional clarity and mental flexibility, leading to a longer life and better health. This model of psychological wellbeing based on the development of human potential and physical exercise, indicates that some aspects of psychological wellbeing are perceived as being more important than others (e.g., self-acceptance, personal growth or life purpose) when studied in relation to autonomy or coping strategies. This study picks perceptions of subjective well-being of adults (N = 482) aged between 24 and 46 years using Scale psychological welfare Ryff's, self-efficacy indicators and persistence questionnaire, all corresponding to the Spanish poblation. The data analysis suggests a positive correspondence between the indices of psychological well-being perceived with the way personal of to oriente and perceive their physical activity. We see the importance of pedagogical transmission of physical activity as a model of psychological well-being as a basis for healthy behaviors in adulthood.ResumenLa práctica de la actividad física es cada vez más im­portante para las personas tanto como actividad recrea­tiva, como actividad de salud. Aunque es difícil encon­trar comportamientos humanos que no tienen ninguna in­fluencia en la salud y el bienestar, es posible señalar conductas entre los factores de riesgo más importantes de los principales problemas de salud como el consumo de alcohol, la obesidad y el tabaco. Programas de ejerci­cio físico saludable regular o actividades autónomas re­gulares y frecuentes, mejoran la salud mental, la auto­nomía, la memoria, la velocidad, la imagen corporal y la sensación de bienestar, produciendo una estabilidad per­sonal caracterizada por el optimismo, la claridad emo­cional y la flexibilidad mental, llevando a una vida más larga y con mejor salud. Este modelo de bienestar psi­cológico basado en el desarrollo del potencial humano y el ejercicio físico, indica que algunos aspectos del bie­nestar psicológico son percibidos como más importantes que otros (por ejemplo, la autoaceptación, el crecimiento personal o el propósito de la vida) cuando se estudian en relación con la autonomía o estrategias de afrontamiento. Este estudio recoge las percepciones del bienestar subje­tivo de los adultos (N = 482) de entre 24 y 46 años utili­zando la escala de bienestar psicológico de Ryff, los in­dicadores de autoeficacia y el cuestionario de persisten­cia, todos ellos correspondientes a la población española. El análisis de los datos sugiere una correspondencia po­sitiva entre los índices de bienestar psicológico percibi­dos, con la forma personal de orientar y percibir su acti­vidad física. Vemos la importancia de la transmisión pe­dagógica de la actividad física como un modelo de bie­nestar psicológico y favorecedor de comportamientos saludables en la edad adultaAbstractPractice of physical activity is increasingly important for people both as a recreational activity as a health activity. Although it is difficult to find human behaviors that do not have any influence on the health and well-being, it´s possible to show conduct that are among the most important risk factors of major health problems today such as consumption alcohol, obesity and snuff. Regular healthy physical exercise following programmes or frequent and regular autonomous activities improves mental health, autonomy, memory, speed, body image and the feeling of wellbeing, while producing personal stability characterised by optimism, emotional clarity and mental flexibility, leading to a longer life and better health. This model of psychological wellbeing based on the development of human potential and physical exercise, indicates that some aspects of psychological wellbeing are perceived as being more important than others (e.g., self-acceptance, personal growth or life purpose) when studied in relation to autonomy or coping strategies. This study picks perceptions of subjective well-being of adults (N = 482) aged between 24 and 46 years using Scale psychological welfare Ryff's, self-efficacy indicators and persistence questionnaire, all corresponding to the Spanish poblation. The data analysis suggests a positive correspondence between the indices of psychological well-being perceived with the way personal of to oriente and perceive their physical activity. We see the importance of pedagogical transmission of physical activity as a model of psychological well-being as a basis for healthy behaviors in adulthood

    Physiological responses in a simulated canarian wrestling contest

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    La Lucha Canaria (LC) ha sido recientemente reconocida como deporte por el Consejo Superior de Deportes, aunque su origen se pierde en el tiempo. Sin embargo, no hay ningún trabajo en la bibliografía científica que describa qué ocurre fisiológicamente durante la competición en esta modalidad de lucha, y éste es el objetivo del presente trabajo. Con una muestra de 12 luchadores de alto nivel (puntales) simulamos el sistema de competición actual en Lucha Canaria. Se estudió la frecuencia cardiaca, la tensión arterial y la concentración de lactato en sangre en diferentes momentos de la simulación. Los patrones observados de respuesta de FC, TA y lactato, caracterizan a la competición en LC como un ejercicio intermitente, con picos de intensidad que superan el umbral láctico y determinan incrementos importantes de FC y TA sistólica. Este estudio es el primero en que se valora la respuesta fisiológica del luchador canario en competición.The aim of this article is to describe what happens from a physiological point of view in a Canarian Wrestling (CW) contest. The Spanish National Sports Council recognized Canarian Wrestling as a sport on June 1st, 2009, although its origin is not very well documented. No scientific article exists in the scientific literature to describe what happens physiologically during a CW contest. Twelve high level wrestlers were recruited to simulate a CW match. The study involved data about heart rate (HR), blood pressure (BP) and blood lactate levels (L) at different moments of the combat. The conclusions of the data observed concerning HR, BP and L classify Canarian Wrestling as an intermittent exercise, with intensity peaks that exceed the lactic threshold and high levels of HR and systolic BP. This is the first paper in which the physiological responses in a Canarian Wrestling competition are reported

    Influence of the Nanostructure of Palladium Mesoparticles on the Kinetics of Molecular Oxygen Electroreduction

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    The effect of the nanostructure of electrodeposited palladium mesoparticles on the oxygen electroreduction reaction (oerr) in acid media is studied by electrochemical techniques combined with scanning tunneling microscopy, tapping-mode atomic force microscopy, and scanning electron microscopy. Palladium mesoparticles supported on highly oriented pyrolytic graphite (HOPG) exhibit a remarkable electrocatalytic enhancement, i.e., a decrease in the cathodic overvoltage on the order of 0.25 V, as compared to polycrystalline palladium electrodes. For a similar particle size, the largest electrocatalytic activity is obtained by use of quasi-twodimensional (2D) ramified palladium particles and electrodeposited palladium charges exceeding 3 mC cm-2. For these particles, experimental results show that the electrocatalytic enhancement of the oerr can be related to the combined influence of the nanostructure of 2D branching on the HOPG and traces of oxygen-containing adsorbates that induces local perturbation of electronic states at palladium mesoparticles. The 2D nature of surfaces increases markedly the reversibility of the first two-electron-transfer step of the oerr.Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicada

    Coherent states in the quantum multiverse

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    In this paper, we study the role of coherent states in the realm of quantum cosmology, both in a second-quantized single universe and in a third-quantized quantum multiverse. In particular, most emphasis will be paid to the quantum description of multiverses made up of accelerated universes. We have shown that the quantum states involved at a quantum mechanical multiverse whose single universes are accelerated are given by squeezed states having no classical analogs.Comment: 7 pages, 3 figure
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