This paper presents and analyzes the potential uses and motivations of online social networks in education, with special emphasis on secondary education. First, we show several previous researches supporting the use of social networking as an educational tool and discuss Edmodo, an educative online social network. The work carried out during two academic years with senior students of primary and secondary schools is also analyzed. After that we present Tweacher an educative social network application and evaluate its use in the classroom to prove its useful use between teachers and students. This research has allowed us to see the reality of social network use among young people and identify the challenges of its application to education environment.

La actividad profesional del arquitecto Félix Hernández (1889Hernández ( -1975 estuvo dedicada en buena parte a las investigaciones arqueológicas en los edificios más notables de la cultura islámica. Este artículo pretende mostrar las intervenciones que en materia de restauración llevó a cabo en la Mezquita-Catedral de Córdoba y los criterios que las guiaron. Apoyado siempre en el rigor de sus investigaciones arqueológicas y documentales, Hernández ha sido el arquitecto que durante un mayor periodo de tiempo ha participado en las labores de conservación de este edificio. Por ese motivo, nos interesa conocer la evolución de su actividad desde la etapa republicana hasta el franquismo y cuáles fueron las influencias en los criterios seguidos en su labor.Palabras clave: Félix Hernández; Mezquita-Catedral; Córdoba; Arquitectura religiosa; Restauración patrimonial. Felix Hernández's (1889-1975 professional activities as an architect were largely devoted to archaeological investigations in the most outstanding buildings of Islamic culture. This article deals with his restoration interventions in the Mosque-Cathedral of Cordoba and the criteria that guided them. Always based on the rigor of his archaeological and documentary research, Hernández was the architect involved for the longest period of time in the conservation work on this building. For this reason, it is interesting to examine the evolution of his activities from the Republican period through the Franco regime and discover the influences on the criteria used in his work. FÉLIX HERNÁNDEZ AND THE RESTORATION OF THE MOSQUE-CATHEDRAL OF CORDOBA

Índice 1. INTRODUCCIÓN XIV XV 6.3. La relación con el entorno 303 6.3.1. El valor del ambiente 303 6.3.2. La recuperación de la imagen 304 6.3.3. El entorno urbano 308 6.3.4. La consideración del límite: andenes y cerramiento 311 6.4. La confirmación de la hipótesis 313 FUENTES 317 REFERENCIAS BIBLIOGRÁFICAS FUNDAMENTALES 319 RESTANTES REFERENCIAS BIBLIOGRÁFICAS 325 ANEXO GRÁFICO 333 5.4. La búsqueda de lo original y el avance del conocimiento 149 5.4.1. La inquietud arqueológica de Félix Hernández 149 5.4.2. Las investigaciones en la Mezquita y la influencia de Gómez-Moreno 3 Para cualquier acercamiento con precisión a las diferentes etapas históricas del edificio es imprescindible la consulta de NIETO CUMPLIDO, Manuel. La Catedral de Córdoba. Córdoba: Obra Social y Cultural de CajaSur, 1998. 4 Esta es la denominación que recibe el muro que sirve de orientación, de tal modo que si se reza mirando hacia ese muro, se está orando en dirección a La Meca. 5 Resulta imprescindible la lectura del nº 256 de la revista Arquitectura, dedicado a la Mezquita-Catedral de Córdoba, entre cuyos artículos cabe destacar los de:

Online social networks are part of our daily life. They are widely used among university students. These platforms have positive and negative aspects. Focusing on the positive aspects, positive reinforcement social networks (PRSNs) have been used to improve the participation of high school students in the classroom. The main objective of this study is to analyze online social interaction on PRSNs, in order to find out if they have a positive impact on classroom participation and students’ self-perceptions of their own social skills, especially in the supposedly difficult STEM (Science, Technology, Engineering and Mathematics) subjects, where engagement tends to be lower. An education-oriented PRSN platform has been developed and used by the experimental group of students to promote discussion and facilitate the sharing of different types of materials. These materials had to be related to students’ academic and professional life, but not necessarily related to Mathematics. A total of 72 Geometry students (K–12) and their teacher participated in a semester-long experimental study. Analyses of the interactions through the proposed platform combined with classroom participation revealed that students from the experimental group showed an improvement not found in the control group. Moreover, perceptions of students’ own online skills were analyzed, showing a positive impact after the experiment.