Suchergebnisse

El objetivo es identificar la producción científica sobre el comportamiento y consumo comunicativo de los menores y los jóvenes en internet utilizando una metodología Social Big Data (SBD). Mediante una revisión sistemática se han identificado 58 documentos académicos publicados entre 2010-2020 (mayo). Se compendian las dimensiones más investigadas, los países con mayor producción científica, el perfil académico de las revistas, las técnicas de investigación basadas en SBD y los hallazgos más relevantes. Las principales conclusiones son que los científicos están utilizando el SBD para, mediante gran cantidad de datos analizados en tiempo real, conocer los usos y efectos de las acciones de los adolescentes en la red así como para crear algoritmos que posibiliten la identificación de tendencias de riesgo adolescente. Se confirma que la producción científica es escasa en revistas de ciencias sociales y la necesaria asociación y coautoría de comunicólogos y sociólogos con científicos de perfil técnico para lograr mayor compresión de la realidad e incrementar las publicaciones en ciencias sociales.

This study examines whether gender is a key factor when producing and uploading audio-visual content to this social network. The research has been carried out using content analysis methodology applied to a sample of 300 videos uploaded to YouTube by adolescents aged 11-17 years, which were collected and analysed during the state of emergency in Spain (13 March – 21 June of 2020) as a result of the COVID-19 pandemic. Contents uploaded by these YouTubers are amusing, and their topics differ significantly depending on the author's gender. Boys focus mainly on playing games, while the range of topics among girls is more diverse. There are no significant differences in the way both genders approach the topic of COVID-19. Channels oriented toward girls are protected from comments their followers might make about them, whereas boys are more exposed to members of the public who view their audio-visual productions.

Military activities have left a legacy of depleted uranium (DU) penetrator waste in the near-surface terrestrial environment. To understand the fate of this DU alloy, the mechanisms and controlling factors of corrosion need to be determined. In this study, field-moist and waterlogged microcosms were used to investigate the effect of redox conditions and soil water content on the corrosion and fate of DU in subsurface soil, and the impact of corroding DU on the soil microbial population. The mechanism of corrosion and the corrosion products formed were highly dependent on the water status of the soil. Under field-moist conditions, DU corroded at a rate of 0.49 ± 0.06 g cm -2 y-1 and the main U input to surrounding soil was large metaschoepite [(UO2)8O2(OH) 12·(H2O)10] particles. However, under waterlogged conditions the rate of corrosion was significantly slower at 0.01-0.02 g cm-2 y-1 and occurred with the release of dissolved species to the surrounding environment. Corrosion ceases under reducing conditions, thus redox conditions are important in determining the persistence of penetrators in the environment. Corroding DU alters the redox conditions in the surrounding environment and both mechanisms of corrosion impact the microbial community. © 2009 American Chemical Society.