Spectropolarimetric analysis of an active region filament. I. Magnetic and dynamical properties from single component inversions

The determination of the magnetic filed vector in solar filaments is possible by interpreting the Hanle and Zeeman effects in suitable chromospheric spectral lines like those of the He I multiplet at 10830 A. We study the vector magnetic field of an active region filament (NOAA 12087). Spectropolarimetric data of this active region was acquired with the GRIS instrument at the GREGOR telescope and studied simultaneously in the chromosphere with the He I 10830 A multiplet and in the photosphere with the Si I 10827 A line. As it is usual from previous studies, only a single component model is used to infer the magnetic properties of the filament. The results are put into a solar context with the help of the Solar Dynamic Observatory images. Some results clearly point out that a more complex inversion had to be done. Firstly, the Stokes $V$ map of He I does not show any clear signature of the presence of the filament. Secondly, the local azimuth map follows the same pattern than Stokes $V$ as if the polarity of Stokes $V$ were conditioning the inference to very different magnetic field even with similar linear polarization signals. This indication suggests that the Stokes $V$ could be dominated by the below magnetic field coming from the active region, and not, from the filament itself. Those and more evidences will be analyzed in depth and a more complex inversion will be attempted in the second part of this series.Comment: 18 pages, 19 figures, accepted for publication in A&

Con fallas activas hay y habrá terremotos

El catastrófico terremoto ocurrido la madrugada del 23 de agosto en la región de Rieti, en Italia central, vuelve a impactarnos al poner de manifiesto el tremendo poder destructor de los sismos de magnitud mayor de 5 y poco profundos en el ámbito Mediterráneo, con unas poblaciones rurales con construcciones altamente vulnerables. Un evento como este puede repetirse en Italia o incluso en España, puesto que allí donde hay fallas activas de gran longitud, ha habido y habrá terremotos

El paradigma de la complejidad como instrumento teórico y metodológico en la investigación didáctica sobre la contaminación y sobre la energía

En dos investigaciones recientes (Cano, 2008; García, Rodríguez y Solís, 2008; Rodríguez, 2008), hemos utilizado el Paradigma de la Complejidad como instrumento teórico que ha orientado el diseño y desarrollo de dichas investigaciones. En la primera investigación (Cano, 2008), se realizó un estudio pormenorizado del proceso de construcción de conocimiento relevante y significativo sobre la contaminación del agua con alumnos de cuarto de ESO. En la segunda (García, Rodríguez y Solís, 2008; Rodríguez, 2008), se realizó una descripción del desarrollo de una experiencia de Agenda 21 Escolar, centrada en el tratamiento didáctico del uso de la energía en Primaria y Secundaria

Micro-Raman and Raman Imaging studies of glassy material produced by continuous wave (CW) CO2 laser irradiation of lime/pozzolan mortar

ICCC 2015, Beijing, China, 13~16 October 2015; http://iccc2015.csp.escience.cn/dct/page/1This work describes the distribution of the portlandite over the surface of the lime/pozzolan mortar and the mineral composition of the glassy material formed when the mortar was irradiated with continuous-wave-CO2 (CW-CO2) laser. Both Micro-Raman and Raman mapping have been used for structural studies. Lime/pozzolan/sand 1/1/2 mortars, 5 years at room temperature, were irradiated with CW-CO2 laser (Synrad Firestar t80, Mukilteo, WA) operating at a wavelength of 10.591 ¿m, 10P(20) CO2 laser line. Laser output: 8W, 18W and 38W (Synrad PW-250 (Mukilteo, WA)). The laser beam was focused by means of a NaCl lens of 10 cm focal length and the irradiation time was 5 seconds. Raman spectra were collected with a Raman Spectrometer (Renishaw Invia) equipped with a CCD camera, using 532 nm (Nd:YAG) excitation line. The laser on the sample was 5 mW and the integration time was 10 seconds. For mapping measurements, an area of 80 ¿m x 80 ¿m was chosen in the internal part of the glass. The step size was 5 ¿m with an individual grid size of 25 ¿m2. Glazing, vaporization and spalling process can produce over an irradiated surface with a high power laser beam. When the power density of the irradiating laser beam is high enough to raise the temperature beyond the glass transition, a glassy surface layer is formed. However, if surface temperatures are below that melting point, the vaporization of water can be produce over the material surface. Due to the small diffusivity of water vapour, its transport is hindered and an overpressure is attained. Hydraulic building materials have about 4-10% bounded water, after irradiation with the CW-CO2 laser, water vapour spread out in a vaporization front reacting with the CaO present in the sample and producing Ca(OH)2, besides a glassy surface.Peer Reviewe

Efficient transfer entropy analysis of non-stationary neural time series

Information theory allows us to investigate information processing in neural systems in terms of information transfer, storage and modification. Especially the measure of information transfer, transfer entropy, has seen a dramatic surge of interest in neuroscience. Estimating transfer entropy from two processes requires the observation of multiple realizations of these processes to estimate associated probability density functions. To obtain these observations, available estimators assume stationarity of processes to allow pooling of observations over time. This assumption however, is a major obstacle to the application of these estimators in neuroscience as observed processes are often non-stationary. As a solution, Gomez-Herrero and colleagues theoretically showed that the stationarity assumption may be avoided by estimating transfer entropy from an ensemble of realizations. Such an ensemble is often readily available in neuroscience experiments in the form of experimental trials. Thus, in this work we combine the ensemble method with a recently proposed transfer entropy estimator to make transfer entropy estimation applicable to non-stationary time series. We present an efficient implementation of the approach that deals with the increased computational demand of the ensemble method's practical application. In particular, we use a massively parallel implementation for a graphics processing unit to handle the computationally most heavy aspects of the ensemble method. We test the performance and robustness of our implementation on data from simulated stochastic processes and demonstrate the method's applicability to magnetoencephalographic data. While we mainly evaluate the proposed method for neuroscientific data, we expect it to be applicable in a variety of fields that are concerned with the analysis of information transfer in complex biological, social, and artificial systems.Comment: 27 pages, 7 figures, submitted to PLOS ON

Estudio de la influencia de la calidad del agua de riego sobre las propiedades bioquímicas del suelo

Trabajo presentado en el VII Simposio Nacional sobre Control de la Degradación y Restauración de Suelos, celebrado en Bilbao, España, del 23 al 26 de junio de 2015Este estudio analiza la influencia de la calidad del agua de riego sobre los parámetros bioquímicos de los Fluvisoles calcáricos representativos en dos zonas del sur de Alicante. Mediante un análisis de componentes principales (ACP) se obtuvo el PC1 (40% variabilidad), referente a la salinidad, siendo útil para diferenciar ambas zonas de estudio, y el PC2 (31%), englobando los parámetros bioquímicos, que distingue las muestras en función de la profundidad. Sin embargo, no se ha observado un efecto negativo sobre las principales actividades enzimáticas en el área más afectada por la salinización.Peer Reviewe

Fracturación y control tectosedimentario neógeno en el borde sureste de la Cuenca de Lorca

En este trabajo se estudia el control tectosedimentario ejercido por la fracturación neógena en la sedimentación en el borde suroriental de la Cuenca de Larca. El control más importante está impuesto por la actividad del Corredor Tectónico de la Falla de Alhama de Murcia. Este corredor controló la formación del borde sur de la citada cuenca a través de movimientos de carácter normal que activaron el inicio del depósito mioceno. Durante el Tortoniense y el Messiniense la cinemática sinestral e inversa del corredor controla la formación del anticlinal que estructura la Sierra de La Tercia y provoca reactivaciones de procesos erosivos en áreas emergidas