Power spectra of velocities and magnetic fields on the solar surface and their dependence on the unsigned magnetic flux density

We have performed power spectral analysis of surface temperatures, velocities, and magnetic fields, using spectro-polarimetric data taken with the Hinode Solar Optical Telescope. When we make power spectra in a field-of-view covering the super-granular scale, kinetic and thermal power spectra have a prominent peak at the granular scale while the magnetic power spectra have a broadly distributed power over various spatial scales with weak peaks at both the granular and supergranular scales. To study the power spectra separately in internetwork and network regions, power spectra are derived in small sub-regions extracted from the field-of-view. We examine slopes of the power spectra using power-law indices, and compare them with the unsigned magnetic flux density averaged in the sub-regions. The thermal and kinetic spectra are steeper than the magnetic ones at the sub-granular scale in the internetwork regions, and the power-law indices differ by about 2. The power-law indices of the magnetic power spectra are close to or smaller than -1 at that scale, which suggests the total magnetic energy mainly comes from either the granular scale magnetic structures or both the granular scale and smaller ones contributing evenly. The slopes of the thermal and kinetic power spectra become less steep with increasing unsigned flux density in the network regions. The power-law indices of all the thermal, kinetic, and magnetic power spectra become similar when the unsigned flux density is larger than 200 Mx cm^-2.Comment: 9 pages, 6 figures, accepted for publication in Ap

Asteroseismology of delta Scuti stars in open clusters: Praesepe

The present paper provides a general overview of the asteroseismic potential of delta Scuti stars in clusters, in particular focusing on convection diagnostics. We give a summarise of the last results obtained by the authors for the Praesepe cluster of which five delta Scuti stars are analysed. In that work, linear analysis is confronted with observations, using refined descriptions for the effects of rotation on the determination of the global stellar parameters and on the adiabatic oscillation frequency computations. A single, complete, and coherent solution for all the selected stars is found, which lead the authors to find important restrictions to the convection description for a certain range of effective temperatures. Furthermore, the method used allowed to give an estimate of the global parameters of the selected stars and constrain the cluster.Comment: 6 pages, 1 figure. Accepted for publication in Communications in Asteroseismolog

Ressenyes

Index de les obres ressenyades: Manuel OLLÉ SESÉ ; José Moisés MARTÍN CARRETERO ; Silvia ESCOBAR ; Carlos CASTRESANA ; Carmen LAMARCA PÉREZ ; Almudena BERNABEU ; Hernán HORMAZÁBAL MALARÉE ; Antonio ARANIBAR QUIROGA ; María Elena RODRÍGUEZ ; José María MEDINA REY ; Carlos SANTOS, Derechos humanos y desarrollo. Justicia universal : el caso latinoamerican

Conciencia fonológica y procesos léxicos de la lectura en estudiantes de inicial 5 años y 2° grado de una institución educativa de Lima Metropolitana

The aim of this research was to establish the relationship between phonological awareness and lexical processes in reading. This study was correlational, longitudinal and its design was not experimental. Thirty six students from a public school in the city of Lima were assessed in two stages: kinder and 2nd grade. The Phonological Awareness Assessment Test - PECO and the Lexical Processes subtests - PROLEC-R were used, both in adapted versions. The results showed that there is no significant relationship between phonological awareness and lexical processes in reading. However, there is a significant relationship between syllable identification task and word reading subtest in speed and reading skills indexes. A significant relationship between syllable identification task and pseudowords reading in reading skills index was found. Also, a significant relationship between syllabic omission task and pseudoword reading in reading skills index was evidenced.El objetivo de la presente investigación fue establecer la relación entre conciencia fonológica y procesos léxicos de la lectura. El estudio fue de tipo correlacional, longitudinal y diseño no experimental. Participaron 36 estudiantes procedentes de una institución educativa estatal de Lima Metropolitana, a quienes se evaluó en dos momentos: inicial 5 años y 2° grado de primaria. Se aplicaron la Prueba para la Evaluación del Conocimiento Fonológico - PECO y los subtest de Procesos Léxicos del PROLEC-R, ambos en sus versiones adaptadas. Los resultados evidenciaron que no existe relación significativa entre la conciencia fonológica y los procesos léxicos de la lectura. No obstante, se encontró una relación significativa entre la tarea identificación silábica y lectura de palabras en los índices de velocidad y habilidad lectora así como con el índice de habilidad lectora de lectura de pseudopalabras. Asimismo, se evidenció una relación significativa entre la tarea omisión silábica y lectura de pseudopalabras en el índice de habilidad lectora.El objetivo de la presente investigación fue establecer la relación entre conciencia fonológica y procesos léxicos de la lectura. El estudio fue de tipo correlacional, longitudinal y diseño no experimental. Participaron 36 estudiantes procedentes de una institución educativa estatal de Lima Metropolitana, a quienes se evaluó en dos momentos: inicial 5 años y 2° grado de primaria. Se aplicaron la Prueba para la Evaluación del Conocimiento Fonológico - PECO y los subtest de Procesos Léxicos del PROLEC-R, ambos en sus versiones adaptadas. Los resultados evidenciaron que no existe relación significativa entre la conciencia fonológica y los procesos léxicos de la lectura. No obstante, se encontró una relación significativa entre la tarea identificación silábica y lectura de palabras en los índices de velocidad y habilidad lectora así como con el índice de habilidad lectora de lectura de pseudopalabras. Asimismo, se evidenció una relación significativa entre la tarea omisión silábica y lectura de pseudopalabras en el índice de habilidad lectora

Conciencia fonológica y procesos léxicos de la lectura en estudiantes de inicial 5 años y 2° grado de una institución educativa de Lima Metropolitana

The aim of this research was to establish the relationship between phonological awareness and lexical processes in reading. This study was correlational, longitudinal and its design was not experimental. Thirty six students from a public school in the city of Lima were assessed in two stages: kinder and 2nd grade. The Phonological Awareness Assessment Test - PECO and the Lexical Processes subtests - PROLEC-R were used, both in adapted versions. The results showed that there is no significant relationship between phonological awareness and lexical processes in reading. However, there is a significant relationship between syllable identification task and word reading subtest in speed and reading skills indexes. A significant relationship between syllable identification task and pseudowords reading in reading skills index was found. Also, a significant relationship between syllabic omission task and pseudoword reading in reading skills index was evidenced.El objetivo de la presente investigación fue establecer la relación entre conciencia fonológica y procesos léxicos de la lectura. El estudio fue de tipo correlacional, longitudinal y diseño no experimental. Participaron 36 estudiantes procedentes de una institución educativa estatal de Lima Metropolitana, a quienes se evaluó en dos momentos: inicial 5 años y 2° grado de primaria. Se aplicaron la Prueba para la Evaluación del Conocimiento Fonológico - PECO y los subtest de Procesos Léxicos del PROLEC-R, ambos en sus versiones adaptadas. Los resultados evidenciaron que no existe relación significativa entre la conciencia fonológica y los procesos léxicos de la lectura. No obstante, se encontró una relación significativa entre la tarea identificación silábica y lectura de palabras en los índices de velocidad y habilidad lectora así como con el índice de habilidad lectora de lectura de pseudopalabras. Asimismo, se evidenció una relación significativa entre la tarea omisión silábica y lectura de pseudopalabras en el índice de habilidad lectora.El objetivo de la presente investigación fue establecer la relación entre conciencia fonológica y procesos léxicos de la lectura. El estudio fue de tipo correlacional, longitudinal y diseño no experimental. Participaron 36 estudiantes procedentes de una institución educativa estatal de Lima Metropolitana, a quienes se evaluó en dos momentos: inicial 5 años y 2° grado de primaria. Se aplicaron la Prueba para la Evaluación del Conocimiento Fonológico - PECO y los subtest de Procesos Léxicos del PROLEC-R, ambos en sus versiones adaptadas. Los resultados evidenciaron que no existe relación significativa entre la conciencia fonológica y los procesos léxicos de la lectura. No obstante, se encontró una relación significativa entre la tarea identificación silábica y lectura de palabras en los índices de velocidad y habilidad lectora así como con el índice de habilidad lectora de lectura de pseudopalabras. Asimismo, se evidenció una relación significativa entre la tarea omisión silábica y lectura de pseudopalabras en el índice de habilidad lectora

Water maser detections in southern candidates to post-AGB stars and Planetary Nebulae

We intended to study the incidence and characteristics of water masers in the envelopes of stars in the post-AGB and PN evolutionary stages. We have used the 64-m antenna in Parkes (Australia) to search for water maser emission at 22 GHz, towards a sample of 74 sources with IRAS colours characteristic of post-AGB stars and PNe, at declination $< -32 \deg$. In our sample, 39% of the sources are PNe or PNe candidates, and 50% are post-AGB stars or post-AGB candidates. We have detected four new water masers, all of them in optically obscured sources: three in PNe candidates (IRAS 12405-6219, IRAS 15103-5754, and IRAS 16333-4807); and one in a post-AGB candidate (IRAS 13500-6106). The PN candidate IRAS 15103-5754 has water fountain characteristics, and it could be the first PN of this class found. We confirm the tendency suggested in Paper I that the presence of water masers in the post-AGB phase is favoured in obscured sources with massive envelopes. We propose an evolutionary scenario for water masers in the post-AGB and PNe stages, in which ``water fountain'' masers could develop during post-AGB and early PN stages. Later PNe would show lower velocity maser emission, both along jets and close to the central objects, with only the central masers remaining in more evolved PNe.Comment: 11 pages, 5 figures. Accepted by Astronomy and Astrophysic

Study of the polarization produced by the Zeeman effect in the solar Mg I b lines

The next generation of solar observatories aim to understand the magnetism of the solar chromosphere. Therefore, it is crucial to understand the polarimetric signatures of chromospheric spectral lines. For this purpose, we here examine the suitability of the three Fraunhofer Mg I b1, b2, and b4 lines at 5183.6, 5172.7, and 5167.3 A, respectively. We start by describing a simplified atomic model of only 6 levels and 3 line transitions for computing the atomic populations of the 3p-4s (multiplet number 2) levels involved in the Mg I b line transitions assuming non-local thermodynamic conditions and considering only the Zeeman effect using the field-free approximation. We test this simplified atom against more complex ones finding that, although there are differences in the computed profiles, they are small compared with the advantages provided by the simple atom in terms of speed and robustness. After comparing the three Mg I lines, we conclude that the most capable one is the b2 line as b1 forms at similar heights and always show weaker polarization signals while b4 is severely blended with photospheric lines. We also compare Mg I b2 with the K I D1 and Ca II 8542 A lines finding that the former is sensitive to the atmospheric parameters at heights that are in between those covered by the latter two lines. This makes Mg I b2 an excellent candidate for future multi-line observations that aim to seamlessly infer the thermal and magnetic properties of different features in the lower solar atmosphere.Comment: 14 pages, 11 figures, and 5 table

Bibliografía de economía regional sobre Castilla y León (1975-1989)

Precede al tít.: Departamento de Economía Aplicada, Facultad de Ciencias Económicas y Empresariales, Universidad de Valladolid