bluuebunny/crossref_metadata_2025_split huggingface dataset:
Variability in the Position of the IBEX Ribbon over Nine Years: More Observational Evidence for a Secondary ENA Source
Authors: Dayeh M. A. , Zirnstein E. J. , Desai M. I. , Funsten H. O. , Fuselier S. A. , Heerikhuisen J. , McComas D. J. , Schwadron N. A. , Szalay J. R. 
Published: July 2019

Abstract
The ribbon of enhanced energetic neutral atom flux, discovered by the Interstellar Boundary Explorer (IBEX) in 2009, has redefined our understanding of the heliosphere’s interaction with the local interstellar medium (LISM). Yet, its origin continues to be a topic of scientific debate. The ribbon is circular and traces the region where the putative LISM magnetic field (B
LISM) is perpendicular to the radial direction from the Sun. Using nine years of IBEX-Hi observations, we investigate the ribbon circularity and location as functions of time and energy. We provide updated locations of the ribbon center at five energy passbands (centered at 0.7, 1.1, 1.7, 2.7, and 4.3 keV) in ecliptic coordinates [longitude, latitude]: [217.°41 ± 0.°95, 44.°36 ± 0.°93], [219.°72 ± 0.°95, 41.°50 ± 0.°87], [220.°51 ± 1.°19, 39.°96 ± 1.°00], [218.°08 ± 1.°66, 38.°44 ± 1.°24], and [214.°68 ± 1.°48, 34.°13 ± 1.°19] respectively. The weighted mean center location over all energies and all years is [218.°33 ± 0.°68, 40.°38 ± 0.°88] and its radius is 74.°81 ± 0.°65. As viewed by IBEX at 1 au, we find that (1) the ribbon is stable over time, with distinct centers at each energy; (2) ribbon centers exhibit small temporal variations, likely caused by the solar wind (SW) speed and density variations; and (3) ribbon location in the sky appears to be driven by (i) the inherent alignment of the ribbon centers along the plane connecting the presumed B
LISM and the heliospheric upwind direction, and (ii) the variable SW structure along the heliographic meridian, further emphasizing that the ribbon source is outside the heliosphere.
Radiation-mediated Shocks in Gamma-Ray Bursts: Subshock Photon Production
Authors: Lundman Christoffer , Beloborodov Andrei M. 
Published: July 2019

Abstract
Internal shocks provide a plausible heating mechanism in the jets of gamma-ray bursts (GRBs). Shocks occurring below the jet photosphere are mediated by radiation. It was previously found that radiation-mediated shocks (RMSs) inside GRB jets are inefficient photon producers, and the photons that mediate the RMS must originate from an earlier stage of the explosion. We show that this conclusion is valid only for nonmagnetized jets. RMSs that propagate in moderately magnetized plasma develop a collisionless subshock that locally heats the plasma to a relativistic temperature, and the hot electrons emit copious synchrotron photons inside the RMS. We find that this mechanism is effective for mildly relativistic shocks and may be the main source of photons observed in GRBs. We derive a simple analytical estimate for the generated photon number per proton, Z, which gives Z = 105–106, consistent with observations. The number is controlled by two main factors: (1) the abundance of electron–positron pairs created in the shock, which is self-consistently calculated, and (2) the upper limit on the brightness temperature of soft radiation set by induced Compton scattering. The photons are initially injected with low energies that are well below the observed GRB peak. The injected soft photons that survive induced downscattering and free–free absorption gain energy in the RMS via bulk Comptonization and shape its nonthermal spectrum.
Comparison of the Asteroseismic Mass Scale of Red Clump Giants with Photometric Mass Estimates
Authors: An Deokkeun , Pinsonneault Marc H. , Terndrup Donald M. , Chung Chul 
Published: July 2019

Abstract
Asteroseismology can provide joint constraints on masses and radii of individual stars. While this approach has been extensively tested for red giant branch (RGB) stars, it has been more difficult to test for helium core–burning red clump (RC) giants because of the lack of fundamental calibrators. To provide independent mass estimates, we utilize a number of widely used horizontal-branch models in the literature and derive photometric masses from a comparison with

photometry. Our selected models disagree with each other on the predicted mass–luminosity–temperature relation. We adopt first-order corrections on colors and magnitudes to minimize the dispersion between different models by forcing models to match the observed location in the solar-metallicity cluster M67. Even for these calibrated models, however, the internal consistency between models deteriorates at higher metallicities, and photometric masses become smaller than asteroseismic masses, as seen from metal-rich field RC stars with Gaia parallaxes. Similarly, the average photometric mass for metal-rich NGC 6791 stars ranges from 0.7 to 1.1 M
⊙, depending on the specific set of models employed. An ensemble average of the photometric masses (0.88 ± 0.16 M
⊙) in NGC 6791 is marginally consistent with the asteroseismic mass (1.16 ± 0.04 M
⊙). There is a clear tension between the masses that one would predict from photometry for metal-rich field RC stars, asteroseismic masses, and those that would be expected from the ages of stars in the Galactic disk populations and canonical RGB mass loss. We conclude that standard RC models need to be reexamined in light of these powerful new data sets.
Testing the Kerr Metric with X-Ray Reflection Spectroscopy of Mrk 335 Suzaku Data
Authors: Choudhury Kishalay , Nampalliwar Sourabh , Abdikamalov Askar B. , Ayzenberg Dimitry , Bambi Cosimo , Dauser Thomas , García Javier A. 
Published: July 2019

Abstract
Einstein’s gravity has undergone extensive tests in the weak field gravitational limit, with results in agreement with theoretical predictions. There exist theories beyond general relativity (GR) which modify gravity in the strong field regime but agree with GR in the weak field. Astrophysical black holes are believed to be described by the Kerr metric and serve as suitable candidates to test strong gravity with electromagnetic radiation. We perform such a test by fitting one Suzaku data set of the narrow-line Seyfert 1 (NLS1) galaxy Mrk 335 with X-ray reflection spectroscopy, using the Johannsen metric to model the black hole spacetime and test for deviations from Kerr. We find the data is best modeled with a hybrid model that includes both partial covering absorption and a reflection component. This is the first time such a model has been proposed for a high-flux (low reflection) Mrk 335 data set. We constrain the Johannsen deformation parameter α
13 to −1.5 < α
13 < 0.6 with spin parameter a
* > 0.8, and the α
22 parameter to −0.4 < α
22 < 2.1 with a
* > 0.7, both at the 99% confidence level. Although additional solutions at large deviations from the Kerr metric show statistical similarity with the ones above, further analysis suggests these solutions may be manifestations of uncertainties beyond our control and do not represent the data. Hence, our results are in agreement with the idea that the supermassive compact object at the center of Mrk 335 is described by the Kerr metric.
Digital resources and didactic methodology in the initial training of History teachers
Authors: Miralles-Martínez Pedro , Gómez-Carrasco Cosme J. , Arias-González Víctor B. , Fontal-Merillas Olaia 
Published: July 2019

This paper analyzes the links that exist between the perceptions of teachers-in-training regarding the use of digital resources in the Secondary Education classroom and their own methodological and epistemological conceptions. Shulman’s theories continue to largely guide current research on teacher knowledge. However, the impact caused by the new technologies has inspired new approaches like T-PACK, which put the focus on the teachers’ digital competence. In order to address this goal, information has been collected by means of a questionnaire implemented in 22 universities, 13 Spanish (344 participants) and 9 British (162 participants). The analysis of data was conducted along three phases: a) examination of the structure of assessments regarding the usefulness of digital resources by analyzing latent classes; b) estimation of confirmatory factor models for variable evaluation processes, History as a formative subject and historical competencies; c) estimation of interclass differences by using confirmatory factor models. The results showed four types of response regarding the use of digital resources in the classroom that were polarized about two items: comics and video games. Important interclass differences have likewise been found regarding methodological issues (traditional and innovative practices), as well as less important differences concerning epistemological conceptions and views on the development of historical competencies in the classroom.
El objetivo de este trabajo es analizar los vínculos entre las percepciones del profesorado en formación sobre el uso de los recursos digitales en el aula de Secundaria, y sus concepciones metodológicas y epistemológicas. Las teorías de Shulman siguen orientando en gran medida las investigaciones sobre el conocimiento del profesorado. Sin embargo, el impacto de las nuevas tecnologías ha impulsado nuevos enfoques, como el T-PACK, que incide en la competencia digital docente. Para abordar este objetivo se ha recogido información de un cuestionario implementado en 22 universidades, 13 españolas (344 participantes) y 9 inglesas (162 participantes). Los análisis de datos se realizaron en tres fases: a) exploración de la estructura de las valoraciones sobre la utilidad de los recursos digitales mediante análisis de clases latentes; b) estimación de los modelos factoriales confirmatorios para las variables procesos de evaluación, Historia como materia formativa, y competencias históricas; c) estimación de las diferencias entre clases. Los resultados mostraron cuatro perfiles de respuesta en función de la opinión sobre el uso de los recursos en el aula, y polarizadas en torno a dos ítems: cómics y videojuegos. También se ha podido comprobar importantes diferencias entre clases en cuestiones metodológicas (prácticas tradicionales e innovadoras); y diferencias menos importantes sobre percepciones epistemológicas y de desarrollo de competencias históricas en el aula.
Online political participation of young people in Mexico, Spain and Chile
Authors: de-la-Garza-Montemayor Daniel-Javier , Peña-Ramos José-Antonio , Recuero-López Fátima 
Published: July 2019

Digital media are present in all areas of society, even configured as a new space for political socialization. This is especially applicable in the case of young people due to their high use of new technologies, as they are also trained with the necessary skills to do so. In this context, social networks have prompted the emergence of a new type of political participation: which takes place online. Therefore, this study delves into the relationship between the socialization that occurs in the network, digital skills and political participation online and offline. A quantitative survey-based methodology was used with university students from three Ibero-American countries: Mexico, Spain and Chile. The fieldwork was conducted between the months of December 2017 and June 2018. The results obtained show that young people consume mainly digital media, which does not prevent them from being critical with the quality they deserve. In this sense, the political participation actions in which they are involved are mostly developed in the network, thus participating to a lesser extent offline. Therefore, young people enter the world of politics through the consumption of information on the Internet, which favors a subsequent online political participation.Los medios digitales están presentes en todos los ámbitos de la sociedad, configurándose incluso como un nuevo espacio para la socialización política. Ello es especialmente aplicable en el caso de los jóvenes debido al elevado uso que realizan de las nuevas tecnologías, al estar capacitados también con las habilidades necesarias para ello. En este contexto, las redes sociales han propiciado el surgimiento de un nuevo tipo de participación política: la que tiene lugar de forma online. Por tanto, esta investigación indaga sobre la relación existente entre la socialización que se produce en la red, las habilidades digitales y la participación política en línea y fuera de línea. Se utiliza una metodología cuantitativa a partir de la realización de encuestas a jóvenes universitarios de México, España y Chile. El trabajo de campo se desarrolló entre los meses de diciembre de 2017 y junio de 2018. Los resultados obtenidos muestran que los jóvenes consumen principalmente medios digitales, lo cual no impide que sean críticos con la calidad que merecen los mismos. En relación con ello, las acciones de participación política en las que se implican se desarrollan en su mayoría en la red, participando así en menor medida fuera de línea. Por tanto, los jóvenes se introducen en el mundo de la política a través de Internet mediante el consumo de información, lo que favorece una posterior participación política online.
Safe and inclusive educational apps: Digital protection from an ethical and critical perspective
Authors: Crescenzi-Lanna Lucrezia , Valente Riccardo , Suárez-Gómez Rafael 
Published: July 2019

The mediated use of technology fosters learning from early childhood and is a potential resource for inclusive education. Nevertheless, the huge range of options and exposure to interactive digital content, which is often online, also implies a series of risks. The definition of protection underlying the current strategies to protect children is inadequate as it only extends to reducing children's exposure to harmful content. This study proposes the expansion of this definition. Through systematic observation of 200 apps within the Catalan sphere for children under 8 years of age and principal component analysis, the results support a multidimensional conceptualisation of protection which, instead of being restricted to the potential risks, also considers aspects related to the educational and inclusive potential of digital resources. Five factors are suggested in order to select these resources and contribute to the digital competence of teachers and students. The first factor concerns the use of protection mechanisms and the existence of external interference, the second factor indicates the presence of adaptation tools; the exposure to stereotypes corresponds to the third factor and the last two consider the previous knowledge required and the verbal component of the apps. Finally, the scope of the suggested definition and its limitations as a guide for future analysis will be discussed.
El uso mediado de la tecnología fomenta el aprendizaje desde la infancia y representa un potencial recurso para la educación inclusiva. Al mismo tiempo, la creciente exposición a contenidos digitales interactivos, a menudo conectados a la red, conlleva una serie de riesgos para los niños. A las estrategias actualmente empleadas para protegerlos, que se limitan a reducir su exposición a contenidos perjudiciales, parece subyacer una definición de protección inadecuada. Esta investigación propone que se amplíe esta definición. A través de una observación sistemática de 200 apps para menores de ocho años en el ámbito catalán y un análisis de componentes principales, se propone una definición multidimensional de protección que no se limita a detallar los riesgos potenciales, sino que también considera aspectos relacionados con el potencial educativo e inclusivo de los recursos digitales. Se sugieren cinco factores a considerar para seleccionar estos recursos y contribuir a la competencia digital de docentes y alumnos. El primer factor concierne al uso de mecanismos de protección y la existencia de interferencias externas; el segundo factor indica la presencia de herramientas de adaptación; la exposición a estereotipos corresponde al tercer factor y los últimos dos consideran los conocimientos previos requeridos y el componente verbal de las apps. Finalmente se discute el alcance de la definición propuesta y sus limitaciones para guiar análisis futuros.
Study of the academic production on communication in Spain and Latin America
Authors: Piñeiro-Naval Valeriano , Morais Ricardo 
Published: July 2019

This paper approaches the state of academic production in communication confined to the Hispanic sphere, namely, Spain and Latin America, during the period extending between 2013 and 2017. As in previous meta-research, the aim here is to highlight potential shortcomings in the discipline, both theoretically and methodologically. From an instrumental standpoint, a systematic, objective and quantitative content analysis was implemented on a probabilistic sample of 1,548 articles from the seven main journals in the field, all indexed in the first quartiles of the SJR-Scopus ranking. Aside from the percentage report for each variable, two-stage cluster analyses were performed twice to identify statistically significant publication patterns. As far as the results are concerned, it is worth highlighting the empirical nature of the studies, generally relying on quantitative methodologies, although no specific theoretical corpora are referenced. On the other hand, and although social networks and ICTs have gained a notable prominence, traditional media continue to be, collectively, the most prominent in communication research. Finally, the challenges of the field seem to revolve around two axes: providing studies with methodological robustness and, above all, with the theoretical background necessary to confront, with guarantees, the understanding of the liquid communicative manifestations that flow, at great speed, from the Information Society.
El presente trabajo aborda el estado de la producción académica en comunicación circunscrita al ámbito hispánico en España e Hispanoamérica durante el período que transcurre de 2013 a 2017. Al igual que en otras metainvestigaciones precedentes, el objetivo aquí radica en poner de manifiesto las posibles carencias de la disciplina, tanto a nivel teórico como metodológico. Desde un punto de vista instrumental, se implementó un análisis de contenido sistemático, objetivo y cuantitativo sobre una muestra probabilística de 1.548 artículos pertenecientes a las siete principales revistas del área, todas ellas indexadas en los primeros cuartiles del ranking SJR-Scopus. Además del reporte porcentual de cada variable, se ejecutaron dos análisis de conglomerados bietápicos para identificar patrones de publicación estadísticamente significativos. En lo que a los resultados respecta, cabe destacar el cariz empírico de los trabajos, apoyados habitualmente en metodologías cuantitativas, aunque sin hacer alusión a corpus teóricos concretos. Por otro lado, y si bien las redes sociales y las TIC han cobrado un notable protagonismo, los medios tradicionales continúan siendo, de manera agregada, los de mayor relieve en la investigación en comunicación. Finalmente, los desafíos del área parece que girarán en torno a dos ejes: nutrir a los estudios de la robustez metodológica y, muy en especial, del acervo teórico necesarios para afrontar, con garantías, la comprensión de las líquidas manifestaciones comunicativas que manan, a gran velocidad, de la Sociedad de la Información.
Foliage est-il à leaves ce que jewellery est à jewels ? Etude de rapports entre dénombrables au pluriel et indénombrables singuliers
Authors: Gardelle Laure 
Published: July 2019

Les recherches sur les noms qui dénotent des pluralités d’unités ont isolé les noms d’agrégats hétérogènes (ainsi jewellery ou furniture). Le présent article cherche à établir s’il faut également considérer comme « noms d’agrégats » des cas passés sous silence tels que foliage, c’est-à-dire des noms au fonctionnement indénombrable eux aussi, mais qui ne s’appliquent pas à des unités hétérogènes, et ne sont donc pas hyperonymiques (au moins dans leur sens central). L’étude conclut que l’hétérogénéité n’est pas un trait définitoire des noms d’agrégats, et qu’il faut y inclure les noms de type foliage. Comme les autres indénombrables étudiés ici, ils présentent une conceptualisation qui fait des unités des parties d’un tout (à la différence des « regroupements » opérés par les N + ‑s, qui dénotent des unités rédupliquées, dont on peut constater les différences, et dont on peut accéder aux parties), et diffèrent des « collectifs », dénombrables, en ce qu’ils ne permettent pas d’attribuer une propriété distributive au tout (heart-shaped foliage / jewellery ne peut par exemple s’appliquer qu’aux feuilles et bijoux individuels). Comme les noms d’agrégats hétérogènes, les noms de type foliage trouvent leur raison d’être dans la mise en avant d’une fonctionnalité commune, au détriment des individualités.Les noms de type foliage présentent une grande différence avec les noms d’agrégats hétérogènes, au-delà de l’absence d’hétérogénéité : les unités sont conceptualisées comme étant fixées à un support (typiquement, une ou des branche(s) pour foliage). Ceci explique que a piece of foliage ne puisse désigner une feuille, alors que a piece of jewellery désigne un bijou. Mais là encore, on conclut que cette différence ne remet pas en cause l’appartenance des noms de type foliage à la classe des noms d’agrégats ; de la même manière, la classe des noms collectifs montre une grande diversité de comportements et de conceptualisations.
Question d'honneur
Authors: Jacotot Mathieu 
Published: July 2019

Est-il légitime d'employer la notion moderne d'« honneur » à propos de la République romaine antique ? Les Romains de cette époque obéissaient-ils à un code de conduite strict ? Sur quoi fondaient-ils le prestige social ? Quelles marques de distinction employaient-ils et à quelles fins ? Telles sont quelques-unes des questions auxquelles cet ouvrage tente de répondre. Pour ce faire, l'auteur analyse trois notions romaines, honos, honestum et honestas, qui recouvrent des objets socio-politiques (marques d'honneur, prestige, charges publiques) et des données morales (dignité de la conduite, bien éthique). Cette diversité est appréhendée dans l'ouvrage par une approche plurielle, relevant de la sémantique, de la sociologie et de l'histoire des idées. L'étude préalable du sens de ces termes dans les textes latins débouche ainsi sur l'examen des pratiques d'hommage et d'honorabilité dans la vie des Romains. Confrontant ensuite la pratique à la théorie, l'ouvrage étudie la manière dont ces trois notions ont été employées comme thèmes littéraires, instruments idéologiques et concepts philosophiques chez les auteurs latins de la République.
Les dieux olympiens et la mer
Authors: Fenet Annick 
Published: July 2019

Si l'affirmation selon laquelle les Grecs sont un peuple de marins peut être nuancée, il est cependant indéniable que la mer représente un aspect géographique majeur du monde grec antique. Il n'est donc guère surprenant que cet élément ait imprégné les croyances et les cultes, et ce depuis l'Atlantique jusqu'au golfe Persique et particulièrement en Grande Grèce. Cet ouvrage explore ainsi les manières dont la culture maritime a influé sur les figures majeures du panthéon grec, les divinités olympiennes, depuis Homère jusqu'à la fin de l'époque hellénistique. Il tempère à cet égard l'importance accordée trop souvent a priori à Poséidon. Toutes les sources ont été requises dans une telle enquête : littéraires, épigraphiques, archéologiques, iconographiques, numismatiques. Par l'analyse des croyances, de la topographie des sanctuaires, des pratiques cultuelles tant à bord qu'à terre et des ex-voto maritimes (ancres et bateaux), il constitue un outil indispensable pour l'étude de la religion grecque comme pour celle de l'archéologie navale.