The ALHAMBRA photometric system

This paper presents the characterization of the optical range of the ALHAMBRA photometric system, a 20 contiguous, equal-width, medium-band CCD system with wavelength coverage from 3500A to 9700A. The photometric description of the system is done by presenting the full response curve as a product of the filters, CCD and atmospheric transmission curves, and using some first and second order moments of this response function. We also introduce the set of standard stars that defines the system, formed by 31 classic spectrophotometric standard stars which have been used in the calibration of other known photometric systems, and 288 stars, flux calibrated homogeneously, from the Next Generation Spectral Library (NGSL). Based on the NGSL, we determine the transformation equations between Sloan Digital Sky Survey (SDSS) ugriz photometry and the ALHAMBRA photometric system, in order to establish some relations between both systems. Finally we develop and discuss a strategy to calculate the photometric zero points of the different pointings in the ALHAMBRA project.Comment: Astronomical Journal on the 14th of January 201

The ALHAMBRA Project: A large area multi medium-band optical and NIR photometric survey

(ABRIDGED) We describe the first results of the ALHAMBRA survey which provides cosmic tomography of the evolution of the contents of the Universe over most of Cosmic history. Our approach employs 20 contiguous, equal-width, medium-band filters covering from 3500 to 9700 A, plus the JHKs bands, to observe an area of 4 sqdeg on the sky. The optical photometric system has been designed to maximize the number of objects with accurate classification by SED and redshift, and to be sensitive to relatively faint emission lines. The observations are being carried out with the Calar Alto 3.5m telescope using the cameras LAICA and O-2000. The first data confirm that we are reaching the expected magnitude limits of AB<~25 mag in the optical filters from the blue to 8300 A, and from AB=24.7 to 23.4 for the redder ones. The limit in the NIR is (Vega) K_s~20, H~21, J~22. We expect to obtain accurate redshift values, Delta z/(1+z) <~ 0.03 for about 5x10^5 galaxies with I<~25 (60% complete), and z_med=0.74. This accuracy, together with the homogeneity of the selection function, will allow for the study of the redshift evolution of the large scale structure, the galaxy population and its evolution with redshift, the identification of clusters of galaxies, and many other studies, without the need for any further follow-up. It will also provide targets for detailed studies with 10m-class telescopes. Given its area, spectral coverage and its depth, apart from those main goals, the ALHAMBRA-Survey will also produce valuable data for galactic studies.Comment: Accepted to the Astronomical Journal. 43 pages, 18 figures. The images have been reduced in resolution to adapt to standard file sizes. Readers can find the full-resolution version of the paper at the ALHAMBRA web site (http://www.iaa.es/alhambra) under the "Publications" lin

Analysis of the Level of Immersion of 360º Video Features Produced by Spanish Media

This paper offers the results of a content analysis on the level of immersion in 360º video features produced by Spanish media. Unlike other conventional ways of storytelling, this new modality provides the viewer with a sensation of being really immerse in a reality that is only being represented, which favors a deeper and more meaningful understanding of it. Our study is divided in three sections. Firstly, we develop a brief theoretical framework that includes the definition and foundations on which immersive feature is based. From this theoretical foundation, we draw a scale to measure the immersion level of these pieces and we confront our proposal to the qualified assessment of 10 experts. Finally we apply this scale on a sample of 148 360º video features produced by Spanish media between January 2015 and December 2017. The aim is to analyze its use and also to infer some good practices that can be useful not only for scholars researching on this new format but also for practitioners producing it.El presente trabajo ofrece los resultados de un análisis de contenido sobre el nivel de inmersión en los vídeos en 360º producidos por medios periodísticos españoles. A diferencia de otras maneras convencionales de contar, esta nueva modalidad genera en el espectador la sensación de encontrarse realmente presente en una realidad que está siendo solo representada. Esto favorece una comprensión más profunda y significativa de ella. Nuestro estudio está dividido en tres secciones. En primer lugar, desarrollamos un breve marco teórico en el que recogemos la definición y fundamentos sobre los que se sostiene el periodismo inmersivo en general y el reportaje en vídeo en 360º en particular. A partir de esta fundamentación, proponemos una escala para medir el nivel de inmersión que hace posible este tipo de piezas y la validamos mediante la evaluación cualificada de un grupo de 10 expertos. Finalmente, aplicamos esta escala sobre una muestra de 148 reportajes en vídeo en 360º publicados por medios periodísticos españoles durante el período comprendido entre enero de 2015 y diciembre de 2017. El objetivo es analizar su uso e inferir una serie de buenas prácticas que puedan resultar de utilidad tanto a académicos que investigan este nuevo formato como a los profesionales que lo producen

Spin precession and spin Hall effect in monolayer graphene/Pt nanostructures

Spin Hall effects have surged as promising phenomena for spin logics operations without ferromagnets. However, the magnitude of the detected electric signals at room temperature in metallic systems has been so far underwhelming. Here, we demonstrate a two-order of magnitude enhancement of the signal in monolayer graphene/Pt devices when compared to their fully metallic counterparts. The enhancement stems in part from efficient spin injection and the large resistivity of graphene but we also observe 100% spin absorption in Pt and find an unusually large effective spin Hall angle of up to 0.15. The large spin-to-charge conversion allows us to characterise spin precession in graphene under the presence of a magnetic field. Furthermore, by developing an analytical model based on the 1D diffusive spin-transport, we demonstrate that the effective spin-relaxation time in graphene can be accurately determined using the (inverse) spin Hall effect as a means of detection. This is a necessary step to gather full understanding of the consequences of spin absorption in spin Hall devices, which is known to suppress effective spin lifetimes in both metallic and graphene systems.Comment: 14 pages, 6 figures. Accepted in 2D Materials. https://doi.org/10.1088/2053-1583/aa882

Low molecular weight ϵ-caprolactone-pcoumaric acid copolymers as potential biomaterials for skin regeneration applications

ϵ-caprolactone-p-coumaric acid copolymers at different mole ratios (ϵ-caprolactone:p-coumaric acid 1:0, 10:1, 8:1, 6:1, 4:1, and 2:1) were synthesized by melt-polycondensation and using 4-dodecylbenzene sulfonic acid as catalyst. Chemical analysis by NMR and GPC showed that copolyesters were formed with decreasing molecular weight as p-coumaric acid content was increased. Physical characteristics, such as thermal and mechanical properties, as well as water uptake and water permeability, depended on the mole fraction of pcoumaric acid. The p-coumarate repetitive units increased the antioxidant capacity of the copolymers, showing antibacterial activity against the common pathogen Escherichia coli. In addition, all the synthesized copolyesters, except the one with the highest concentration of the phenolic acid, were cytocompatible and hemocompatible, thus becoming potentially useful for skin regeneration applications

Non-parametric mass reconstruction of A1689 from strong lensing data with SLAP

We present the mass distribution in the central area of the cluster A1689 by fitting over 100 multiply lensed images with the non-parametric Strong Lensing Analysis Package (SLAP, Diego et al. 2004). The surface mass distribution is obtained in a robust way finding a total mass of 0.25E15 M_sun/h within a 70'' circle radius from the central peak. Our reconstructed density profile fits well an NFW profile with small perturbations due to substructure and is compatible with the more model dependent analysis of Broadhurst et al. (2004a) based on the same data. Our estimated mass does not rely on any prior information about the distribution of dark matter in the cluster. The peak of the mass distribution falls very close to the central cD and there is substructure near the center suggesting that the cluster is not fully relaxed. We also examine the effect on the recovered mass when we include the uncertainties in the redshift of the sources and in the original shape of the sources. Using simulations designed to mimic the data, we identify some biases in our reconstructed mass distribution. We find that the recovered mass is biased toward lower masses beyond 1 arcmin (150 kpc) from the central cD and that in the very center we may be affected by degeneracy problems. On the other hand, we confirm that the reconstructed mass between 25'' and 70'' is a robust, unbiased estimate of the true mass distribution and is compatible with an NFW profile.Comment: 11 pages, 12 figures. MNRAS submitted. A full resolution of the paper can be found in http://darwin.physics.upenn.edu/SLAP

Desarrollo de las competencias específicas relacionadas con la tecnología para las áreas de periodismo y comunicación audiovisual

Makings changes to learning standards that are suggested by EHEA are a good opportunity to enhance students’ professional competences about Journalism and Media Production. This approach involves difficult challenges, like skills in audiovisual technologies and limited resources to apply it. A combined methodology is proposed, putting together positive elements from self-learning, from collaboration environment, from the use of IT and from team work. Participating students have answered a survey asking them about the audiovisual technology role in their training and in the professional environment, and have produced some didactic videos their fellows could see to improve their skills in the use of technology.El cambio hacia los estándares formativos que moviliza el EEES constituye una oportunidad para mejorar el enfoque de la capacitación de los estudiantes de las áreas de Comunicación para el ejercicio profesional. Esta adaptación afronta algunos retos complicados, como son el necesario uso de las tecnologías audiovisuales o los recursos limitados para aplicarla. Se propone una metodología combinada, que reúne elementos positivos de la autoformación, del aprendizaje en entornos colaborativos, del uso de las TIC y del trabajo en equipo. Los alumnos participantes han contestado a un cuestionario que les pregunta sobre el papel de la tecnología audiovisual en su formación y en el entorno profesional y han realizado vídeos didácticos para ser utilizados por sus compañeros en la mejora de las capacidades de uso de la tecnología

Exact solution of the two-dimensional Dirac oscillator

In the present article we have found the complete energy spectrum and the corresponding eigenfunctions of the Dirac oscillator in two spatial dimensions. We show that the energy spectrum depends on the spin of the Dirac particle.Comment: revtex, 6pp. IVIC-CFLE 93/0

Dispersal of the monarch butterfly (Danaus plexippus) over southern Spain from its breeding grounds

Dispersión de la mariposa monarca (Danaus plexippus) en el sur de España desde las zonas de apareamiento Durante el período comprendido entre los años 2000 y 2016, se detectaron mariposas monarca en 127 lugares fuera de las zonas costeras donde se reproducen habitualmente en el sur de la península ibérica. Estos datos se obtuvieron en verano e invierno, coincidiendo con la máxima abundancia de individuos y la mayor proporción de sitios ocupados en sus zonas de reproducción cercanas al estrecho de Gibraltar. Los individuos que se dispersan no tienen ninguna posibilidad de establecer nuevas colonias en estos sitios porque las plantas en las que ponen los huevos no crecen en las localidades en las que fueron detectados. Sin embargo, estos movimientos de dispersión podrían ser la causa de la colonización de plantas alimentarias que crecen en otras zonas de la península ibérica y en otros países del Mediterráneo.From 2000–2016, monarch butterflies were detected at 127 locations away from their usual coastal breeding areas in the south of the Iberian peninsula. These findings were recorded in the summer–autumn period, coinciding with the highest abundance of individuals and the highest proportion of patches occupied in their reproduction areas near the Strait of Gibraltar. These dispersing individuals have no chance of successfully establishing new colonies at these sites because the food plants for egg laying do not grow in the localities where they were detected. However, these dispersive movements could be the source of their successful colonisation on food plants growing in other areas of the Iberian peninsula and in other Mediterranean countries.Dispersión de la mariposa monarca (Danaus plexippus) en el sur de España desde las zonas de apareamiento Durante el período comprendido entre los años 2000 y 2016, se detectaron mariposas monarca en 127 lugares fuera de las zonas costeras donde se reproducen habitualmente en el sur de la península ibérica. Estos datos se obtuvieron en verano e invierno, coincidiendo con la máxima abundancia de individuos y la mayor proporción de sitios ocupados en sus zonas de reproducción cercanas al estrecho de Gibraltar. Los individuos que se dispersan no tienen ninguna posibilidad de establecer nuevas colonias en estos sitios porque las plantas en las que ponen los huevos no crecen en las localidades en las que fueron detectados. Sin embargo, estos movimientos de dispersión podrían ser la causa de la colonización de plantas alimentarias que crecen en otras zonas de la península ibérica y en otros países del Mediterráneo