Modeling non-thermal emission from stellar bow shocks

Runaway O- and early B-type stars passing throughout the interstellar medium at supersonic velocities and characterized by strong stellar winds may produce bow shocks that can serve as particle acceleration sites. Previous theoretical models predict the production of high energy photons by non-thermal radiative processes, but their efficiency is still debated. We aim to test and explain the possibility of emission from the bow shocks formed by runaway stars traveling through the interstellar medium by using previous theoretical models. We apply our model to AE Aurigae, the first reported star with an X-ray detected bow shock, to BD+43 3654, in which the observations failed in detecting high energy emission, and to the transition phase of a supergiant star in the late stages of its life.From our analysis, we confirm that the X-ray emission from the bow shock produced by AE Aurigae can be explained by inverse Compton processes involving the infrared photons of the heated dust. We also predict low high energy flux emission from the bow shock produced by BD+43 3654, and the possibility of high energy emission from the bow shock formed by a supergiant star during the transition phase from blue to red supergiant.Bow shock formed by different type of runaway stars are revealed as a new possible source of high energy photons in our neighbourhood

Temporal and spatial variations of the absolute reflectivity of Jupiter and Saturn from 0.38 to 1.7 μ\mum with PlanetCam-UPV/EHU

We provide measurements of the absolute reflectivity of Jupiter and Saturn along their central meridians in filters covering a wide range of visible and near-infrared wavelengths (from 0.38 to 1.7 $\mu$m) that are not often presented in the literature. We also give measurements of the geometric albedo of both planets and discuss the limb-darkening behavior and temporal variability of their reflectivity values for a period of four years (2012-2016). This work is based on observations with the PlanetCam-UPV/EHU instrument at the 1.23 m and 2.2 m telescopes in Calar Alto Observatory (Spain). The instrument simultaneously observes in two channels: visible (VIS; 0.38-1.0 $\mu$m) and short-wave infrared (SWIR; 1.0--1.7 $\mu$m). We obtained high-resolution observations via the lucky-imaging method. We show that our calibration is consistent with previous independent determinations of reflectivity values of these planets and, for future reference, provide new data extended in the wavelength range and in the time. Our results have an uncertainty in absolute calibration of 10--20\%. We show that under the hypothesis of constant geometric albedo, we are able to detect absolute reflectivity changes related to planetary temporal evolution of about 5-10\%.Comment: 13 pages, 18 figures, (in press

Formation of X-ray emitting stationary shocks in magnetized protostellar jets

X-ray observations of protostellar jets show evidence of strong shocks heating the plasma up to temperatures of a few million degrees. In some cases, the shocked features appear to be stationary. They are interpreted as shock diamonds. We aim at investigating the physics that guides the formation of X-ray emitting stationary shocks in protostellar jets, the role of the magnetic field in determining the location, stability, and detectability in X-rays of these shocks, and the physical properties of the shocked plasma. We performed a set of 2.5-dimensional magnetohydrodynamic numerical simulations modelling supersonic jets ramming into a magnetized medium and explored different configurations of the magnetic field. The model takes into account the most relevant physical effects, namely thermal conduction and radiative losses. We compared the model results with observations, via the emission measure and the X-ray luminosity synthesized from the simulations. Our model explains the formation of X-ray emitting stationary shocks in a natural way. The magnetic field collimates the plasma at the base of the jet and forms there a magnetic nozzle. After an initial transient, the nozzle leads to the formation of a shock diamond at its exit which is stationary over the time covered by the simulations (~ 40 - 60 yr; comparable with time scales of the observations). The shock generates a point-like X-ray source located close to the base of the jet with luminosity comparable with that inferred from X-ray observations of protostellar jets. For the range of parameters explored, the evolution of the post-shock plasma is dominated by the radiative cooling, whereas the thermal conduction slightly affects the structure of the shock.Comment: Accepted for publication in Astronomy and Astrophysic

La formación continua del profesorado en educación intercultural: estereotipos y heurísticos

Esta comunicación tiene por objetivo abordar la importancia de la educación intercultural en la formación continua del profesorado. Se pretende, por un lado, examinar los contenidos que la formación en educación intercultural para profesorado debe incluir y, por otro, analizar las necesidades, conocimientos y la situación de los docentes. Primeramente, se realiza un repaso teórico de los diferentes aspectos que la educación intercultural abarca y a continuación, se presenta la experiencia docente y la línea de investigación sobre la competencia intercultural llevada a cabo entre el profesorado de Primaria y Secundaria participante en el curso “La Educación Intercultural en la Práctica” de Formación Permanente ofrecido por el Departamento de Educación del Gobierno Vasco. Así, en la formación del profesorado se parte del propio conocimiento y la reflexión continua sobre las experiencias profesionales. Aunque un sector del profesorado todavía no ha recibido nunca formación sobre competencias interculturales, muchos docentes valoran la necesidad de formarse porque tienen el reto diario de abordar la diversidad en el centro educativo. Por lo tanto, se parte de la reflexión sobre la práctica y se interrelaciona la teoría y la práctica constantemente. Con respecto a los contendidos, resulta necesario definir, formular y explicar adecuadamente varias cuestiones: ¿Qué es y qué no es educación intercultural?, ¿Cómo ampliar el repertorio de prácticas inclusivas y metodologías para la diversidad?, ¿Por qué los estereotipos y prejuicios suponen un obstáculo para la convivencia intercultural? etc. En efecto, la mayoría de los expertos entienden la educación intercultural (Aguado, Gil Jaurena y Mata, 2005; Besalú, 2002; Carbonell, 2000) desde un enfoque holístico e inclusivo, y como un proceso de transformación que envuelve a toda la comunidad educativa con el fin de construir la equidad educativa y la justicia social. Así, las competencias y temas a desarrollar en un programa de formación son amplios y variados: La educación intercultural y el alumnado (necesidades del alumnado, convivencia escolar…), el profesorado (curriculum intercultural, practicas inclusivas…), las familias (participación en el contexto educativo, formación…), la organización escolar (utilización de recursos comunitarios, proyectos educativos…), etc. Finalmente, con respecto a la línea de investigación sobre la competencia intercultural del profesorado, se analiza cuáles son los estereotipos más comunes que el profesorado posee sobre el alumnado inmigrante y cómo influye el razonamiento heurístico en los juicios y consideraciones sobre la inmigración. Para ello, se proponen distintas acciones educativas de cara a prevenir estos efectos negativos y promover así la educación en y para la diversidad. En definitiva, como se recogen en las directrices de la UNESCO (2006) es necesaria una formación docente inicial adecuada y una formación profesional permanente que brinde a los profesores, entre otros aspectos, una profunda comprensión del paradigma intercultural en la educación y su importancia para la transformación de la práctica cotidiana en las aulas, las escuelas y las comunidades. Y, para ello, es necesario seguir investigando cómo se forman y cómo funcionan los estereotipos y sus relaciones con el razonamiento heurístico

The effect of magnetic activity saturation in chromospheric flux-flux relationships

We present a homogeneous study of chromospheric and coronal flux-flux relationships using a sample of 298 late-type dwarf active stars with spectral types F to M. The chromospheric lines were observed simultaneously in each star to avoid spread due to long term variability. Unlike other works, we subtract the basal chromospheric contribution in all the spectral lines studied. For the first time, we quantify the departure of dMe stars from the general relations. We show that dK and dKe stars also deviate from the general trend. Studying the flux-colour diagrams we demonstrate that the stars deviating from the general relations are those with saturated X-ray emission and that those stars also present saturation in the H$\alpha$ line. Using several age spectral indicators, we show that they are younger stars than those following the general relationships. The non-universality of flux-flux relationships found in this work should be taken into account when converting between fluxes in different chromospheric activity indicators.Comment: Accepted for publication in the Monthly Notices of the Royal Astronomical Societ

Research plan for the Spanish exploratory longline fishery for Dissostichus spp. in Divisions 58.4.1 and 58.4.2: preliminary results of stage 1 (2012/13 season)

During the 2012/13 season Spain started the approved multi-year research survey in Divisions 58.4.1 and 58.4.2 in order to obtain information to better understand the population dynamics of both species of Dissostichus in areas off the Antarctic continent close to the Ross Sea and Banzare Bank, and to implement the use both local depletion and tag-recapture methods in areas described so as to estimate local abundance. The research plan, as it was stated in the proposal, takes several years to be completed. It has started in the SSRUs closest to the Ross Sea, 58.4.1H and G, during the 2012/13 season. In order to fix the protocols and ascertain the viability and suitability of the study, it was establish the return to the same areas the two-three subsequent years along with the movement to new places and westwards to SSRUs 58.4.1D, C, B and 58.4.2E is expected. The vessel Tronio has started the research plan after the exploratory fishing season in the Subarea 88.1, using the Spanish bottom longline system. A total of 42 research sets were performed within the SSRUs 58.4.1H and 58.4.1G. Two depletion experiments were completed and three prospecting-phase clusters of sets did not reach the established threshold to start the depletion. A prospective estimation of the local biomass (BLOC) of the two localized areas where the depletion experiments were performed is done and regarding the maximal and minimal biomass for the SSRUs (BSSRU) considering areas with high and low densities. This study will be reviewed and completed the upcoming years with the new data obtained revisiting the same areas as well as with the tag-recapture data in order to estimate the local abundance using two different approaches, depletion and tag-recapture methods. A summary of the activities and results from the survey is also presented related to the sampling scheme, collected samples and species

Research plan for the exploratory fisheries for Dissostichus spp. in Divisions 58.4.1 and 58.4.2 in 2013/14

The Spanish vessel Tronio started the research plan in the 2012/13 season using the Spanish bottom longline system. One depletion experiments was completed in each of the SSRU surveyed (58.4.1H and 58.4.1G). Three prospecting-phase clusters of sets did not reach the established threshold to start the depletion. A prospective estimation of the local biomass (BLOC) of the two localized areas where the depletion experiments were performed is done as well as an estimation of the biomass of the SSRUs (BSSRU), maximal and minimal, considering areas with high and low densities. A summary of the activities and results from the survey is also presented related to the sampling scheme, collected samples and species involved

Results of the Spanish exploratory longline fishery for Dissostichus spp. in divisions 58.4.1 and 58.4.2 in the 2013/14 season.

Following the Spanish research plan approved by the SC-CCAMLR XXXII, during the second year of the multi-year research survey in Divisions 58.4.1 and 58.4.2, the F/V Tronio has returned to the same places surveyed in the 2012/13 season, as well as expanded the experience westwards to the 58.4.1D and 58.4.1C SSRUs. A prospective estimation of the local biomass (BLOC) of one localized area that was visited for the commercial Spanish fleet along five seasons in the SSRU 58.4.1C is made, together with the estimation of the total Biomass in the entire SSRU using a depletion model. There have been some Antarctic toothfish recaptured that would allow, in successive years, to estimate the local abundance by tag-recapture models. The IEO is starting the process of reading otoliths with ageing purposes, data to be added in order to carry out a robust assessment of Dissotichus eleginoides stock in these divisions. Results of other data collected such as fish bycatch, incidental catch of benthic taxa or otoliths collection for ageing purposes are also presented

Control difuso de la tasa de transferencia de extremo a extremo en protocolos de transporte de Internet

La dinámica del tráfico de extremo a extremo en Internet es un problema complejo para el cual los modelos disponibles son, en el mejor de los casos incompletos. Esta comunicación describe nuevos mecanismos para regulación de la tasa de transferencia de extremo a extremo en la capa de transporte por medio de sistemas difusos. Se describen una generalización basada en lógica difusa de los mecanismos de control de flujo y congestión de TCP (Transport Control Protocol), el diseño de un regulador difuso basado en mecanismo de ventana para TCP, así como la metodología de diseño empleada para simular e implementar de manera experimental el sistema. Se resume un estudio comparativo del regulador difuso presentado frente a los mecanismos tradicionales. El regulador difuso resulta útil como enfoque de modelado y proporciona significativas mejoras de prestaciones respecto a un conjunto de criterios.Ministerio de Educación y Ciencia TEC2005-04359/MICJunta de Amdalucía TIC2006-63

Open FPGA-based development platform for fuzzy systems with applications to communications

Soft computing techniques are gaining momentum as tools for network traffic modeling, analysis and control. Efficient hardware implementations of these techniques that can achieve real-time operation in high-speed communications equipment is however an open problem. This paper describes a platform for the development of fuzzy systems with applications to communications systems, namely network traffic analysis and control. An FPGA development board with PCI interface is employed to support an open platform that comprises open CAD tools as well as IP cores. For the development process, we set up a methodology and a CAD tools chain that cover from initial specification in a high-level language to implementation on FPGA devices. PCI compatible fuzzy inference modules are implemented as SoPC based on the open WISHBONE interconnection architecture. We outline results from the design and implementation of fuzzy analyzers and regulators for network traffic. These systems are shown to satisfy operational and architectural requirements of current and future high-performance routing equipment.Ministerio de Educación y Ciencia TEC2005-04359/MICJunta de Andalucía TIC2006-63