4,424 research outputs found

    Mass loss from an extreme OH/IR star: OH 26.5+0.6

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    Observations of H_{2}O isotopologues of the extreme OH/IR star OH 26.5+0.6 show that the star has an initial mass consistent with it being an intermediate-mass star. The HerschelHIFI spectra show clear detection of H_{2}^{16}O and H_{2}^{17}O while H_{2}^{18}O is missing, consistent with the prediction of hot bottom burning which occurs in stars with an initial mass ≥ 5 M_{ʘ}. The star is currently losing mass at a high rate of a few 10^{-4} M_{ʘ} yr^{-1} which is thought to commence in the past ∼ 200 years. We present new ALMA CO J=3-2 image which show that this high mass loss (superwind) region is compact, surrounded by extended shells of lower mass loss

    Efectos del entrenamiento interválico de alta intensidad durante el periodo transitorio en jugadores de fútbol sub-19

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    Actualmente existe un creciente interés por la aplicación del entrenamiento interválico de alta intensidad (HIIT) en fútbol (Buchheit et al. 2013). La eficacia mostrada por esta metodología de entrenamiento para mejorar las variables del rendimiento ha provocado una mayor aplicación en deportes colectivos (Iaia et al. 2009). Sin embargo, es escasa la literatura científica acerca de su impacto en fútbol. Por ello, el objetivo del trabajo es comparar los efectos sobre el rendimiento del HIIT versus entrenamiento tradicional durante el periodo transitorio invernal en jugadores de fútbol sub-19

    Revista del Consejo Superior de Investigaciones Científicas

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    Actividad trófica de limícolas invernantes en salinas y cultivos piscícolas de la bahía de CádizUso de microhábitat del ratón de campo (Apodemus sylvatycus L.) en robledales y áreas ecotonales del Pirineo.Dieta de los pollos de tres especies simpátricas de alcaudones (Lanius spp.): variaciones con la edad, estacionales e interespecíficasOcupación de distintos modelos de nidal por el estornino negro (Sturnus unicolor)Estudio comparado sobre la biología de la reproducción de tres especies simpátricas de alcaudones (real Lanius excubitor, dorsirrojo L. collurio y común L. senatorFluctuación estacional del peso corporal de los machos adultos de Arvicola sapidus MILLER, 1908 (Rodentia, Arvicolidae)Acerca del significado de los ataques de alcaudones Lanius spp. sobre aves.Distribución de los emididos Mauremys leprosa, SCHW (1812) y Emys orbicularis, L. (1758) de la provincia de Badajoz. Factores que puedieran influir en sus áreas de ocupaciónDeterminación de la edad relativa en la rata de agua meridional, Arvicola sapidus MILLER, 1908 (Rodentia, Arvicolidae)Activity pattern, home range and habitat preference by coyotes (Canis latrans) in the Mapimi Biosphere Reserve of the Chihuahuan Desert, Mexico.Características de los refugios diarios y estacionales de Testudo graeca en DoñanaDieta del gato cimarrón (Felis catus L.) en el piso basal del Macízo de Teno (Noroeste de Tenerife)Peer reviewe

    StarHorse: A Bayesian tool for determining stellar masses, ages, distances, and extinctions for field stars

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    Understanding the formation and evolution of our Galaxy requires accurate distances, ages and chemistry for large populations of field stars. Here we present several updates to our spectro-photometric distance code, that can now also be used to estimate ages, masses, and extinctions for individual stars. Given a set of measured spectro-photometric parameters, we calculate the posterior probability distribution over a given grid of stellar evolutionary models, using flexible Galactic stellar-population priors. The code (called {\tt StarHorse}) can acommodate different observational datasets, prior options, partially missing data, and the inclusion of parallax information into the estimated probabilities. We validate the code using a variety of simulated stars as well as real stars with parameters determined from asteroseismology, eclipsing binaries, and isochrone fits to star clusters. Our main goal in this validation process is to test the applicability of the code to field stars with known {\it Gaia}-like parallaxes. The typical internal precision (obtained from realistic simulations of an APOGEE+Gaia-like sample) are 8%\simeq 8\% in distance, 20%\simeq 20\% in age,6 \simeq 6\ % in mass, and 0.04\simeq 0.04 mag in AVA_V. The median external precision (derived from comparisons with earlier work for real stars) varies with the sample used, but lies in the range of [0,2]%\simeq [0,2]\% for distances, [12,31]%\simeq [12,31]\% for ages, [4,12]%\simeq [4,12]\% for masses, and 0.07\simeq 0.07 mag for AVA_V. We provide StarHorse distances and extinctions for the APOGEE DR14, RAVE DR5, GES DR3 and GALAH DR1 catalogues.Comment: 21 pages, 12 figures, accepte

    Pervasive surveillance-agent system based on wireless sensor networks: design and deployment

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    Nowadays, proliferation of embedded systems is enhancing the possibilities of gathering information by using wireless sensor networks (WSNs). Flexibility and ease of installation make these kinds of pervasive networks suitable for security and surveillance environments. Moreover, the risk for humans to be exposed to these functions is minimized when using these networks. In this paper, a virtual perimeter surveillance agent, which has been designed to detect any person crossing an invisible barrier around a marked perimeter and send an alarm notification to the security staff, is presented. This agent works in a state of 'low power consumption' until there is a crossing on the perimeter. In our approach, the 'intelligence' of the agent has been distributed by using mobile nodes in order to discern the cause of the event of presence. This feature contributes to saving both processing resources and power consumption since the required code that detects presence is the only system installed. The research work described in this paper illustrates our experience in the development of a surveillance system using WNSs for a practical application as well as its evaluation in real-world deployments. This mechanism plays an important role in providing confidence in ensuring safety to our environment

    Sutton Naevi as melanoma simulators: Can confocal microscopy help in the diagnosis?

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    Sutton naevi can sometimes present a challenging appearance with atypical presentation, also by dermoscopy. Reflectance confocal microscopy could help in making a diagnosis. This study prospectively collected two groups of Sutton nevi: the first one was composed by typical white halo naevi monitored for one year (13, 23%) and the second one was made up of atypical lesions excised in order to rule out melanoma, which were histologically diagnosed as Sutton naevi (21, 37%). These two groups of Sutton naevi were compared to a retrospectively collected cohort of thin melanomas with histologic regression features (23, 40%). On dermoscopy, atypical Sutton naevi and melanomas were indistinguishable. Reflectance confocal microscopy demonstrated significant differences at the dermo-epidermal junction: marked dermo-epidermal junction thickening and non-edged papilla were associated with melanoma, while the presence of nests was associated with Sutton naevi. However, reflectance confocal microscopy also detected marked intraepidermal pagetoid cells in Sutton naevi that were a combination of MelanA+ and CD1a+ cells. Sutton naevi can simulate melanoma, under both dermoscopy and reflectance confocal microscopy. Nevertheless, relevant confocal dermo-epidermal junction features and the clinical scenario can be helpful to make a final diagnosis, especially in those situations where melanoma must be ruled out

    Analysis of the Use and Applicability of Different Variables for the Prescription of Relative Intensity in Bench Press Exercise

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    The aim of the study was to analyze the use of variables such as % of one-repetition maximum (1RM) and number of maximal repetitions (xRM) with execution velocity to define and control the intensity of resistance training in bench press exercise. Hence, exercise professionals will achieve better control of training through a greater understanding of its variables. Methods: In this cross-sectional study, fifty male physical education students were divided into four groups according to their relative strength ratio (RSR) and performed a 1RM bench press test (T1). In the second test, participants performed repetitions to exhaustion (T2), using a relative load corresponding to 70% 1RM determined through the mean propulsive velocity (MPV) obtained from the individual load–velocity relationship. This same test was repeated a week later (T3). Tests were monitored according to the MPV of each repetition and blood lactate values (LACT). Results: Regarding MPV, the best (fastest) repetition of the set (MPVrep Best) values were similar between groups (0.62 m·s−1–0.64 m·s−1), with significant differences in relation to the high RSR group (p 0.05). Average LACT values (5.72 mmol·L−1) showed significant differences between the Background: Medium RSR and Very Low RSR groups. No significant differences were found (p > 0.05) between T2 and T3 with regards to MNR, MPVrep Best, or MPVrep Last, with little variability seen between participants. Conclusions: The use of variables such as the 1RM, estimated using an absolute load value, or an MNR do not allow an adequate degree of precision to prescribe and control the relative intensity of resistance training. Besides, execution velocity control can offer an adequate alternative to guarantee an accurate prescription of intensity with regard to resistance training.Sección Deptal. de Radiología, Rehabilitación y Fisioterapia (Enfermería)Fac. de Enfermería, Fisioterapia y PodologíaTRUEpu

    Realization of Polarization Control in High-Order Harmonic Generation

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    The nature of high-order harmonic generation process limits the harmonics emission to linear polarization. In this paper, we review the recent progress to generate elliptically or circularly polarized high-harmonic EUV pulses. We further demonstrate how complete control of polarization state of isolated high-harmonic pulse can be realized today by noncollinear focusing of two driving pulses with identical ellipticity but counter-rotating helicity. This paper opens a path towards the study of the fastest dynamics--down to attosecond time scales--in circular dichroism of magnetic materials, chiral molecules, and electronic spin motion.Taiwan Ministry of Science and Technology; Academia Sinica; Junta de Castilla y León; Ministerio de Economía y Competitividad; Leonardo Grant for Researchers and Cultural Creators, BBVA Foundation; Ministerio de Ciencia, Innovación y Universidades for a Ramón y Cajal; European Social Fund; Ministerio de Educación, Cultura y Deporte

    FAP- Anion Ionic Liquids Used in the Lubrication of a Steel–Steel Contact

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    This study compares the tribological behavior of two ionic liquids ([BMP][FAP] and [(NEMM)MOE][FAP]) used as oil additive for the lubrication of a steel–steel contact. Friction and wear experiments were performed using a HFRR test machine. Friction coefficient and electrical contact resistance were measured during the tests, and the wear surface was analyzed by confocal microscopy and XPS. The tribological results showed that both ionic liquids used as additive decrease friction and wear but the [BMP][FAP] had a better performance than the [(NEMM)MOE][FAP] due to its higher reactivity with the steel
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