Teaching & Learning The Spanish Aspect Using Blogs and Wikis: An Exploratory Study

This study investigated the influence of asynchronous computer text based technologies on the students’ performance when learning the preterite and the imperfect aspects in Spanish. Two research questions guided the study: Research Question 1) Is there a difference in students’ achievement levels in Spanish preterite and imperfect between those using wiki technologies and those using blog technologies after controlling for pre-intervention achievement levels? and Research Question 2) Are there differences in satisfaction levels for students learning Spanish preterite and imperfect via blog technologies as compared to those learning via wiki technologies? Results indicate that there were not significant differences between students who use blog or wiki technologies on performance levels when controlling for pre-existing knowledge. Results also indicated that there were not significant differences in satisfaction levels between those students using a wiki and those using a blog. These results suggest that wikis and blogs are good potential tools that may facilitate the teaching and learning of problematic grammar structures in a narrative context

Laser-Controlled Real- and Reciprocal-Space Topology in Multiferroic Insulators

Magnetic materials in which it is possible to control the topology of their magnetic order in real space or the topology of their magnetic excitations in reciprocal space are highly sought after as platforms for alternative data storage and computing architectures. Here we show that multiferroic insulators, owing to their magnetoelectric coupling, offer a natural and advantageous way to address these two different topologies using laser fields. We demonstrate that via a delicate balance between the energy injection from a high-frequency laser and dissipation, single skyrmions—archetypical topological magnetic textures—can be set into motion with a velocity and propagation direction that can be tuned by the laser field amplitude and polarization, respectively. Moreover, we uncover an ultrafast Floquet magnonic topological phase transition in a laser-driven skyrmion crystal and we propose a new diagnostic tool to reveal it using the magnonic thermal Hall conductivity

Majorana Bound States Induced by Antiferromagnetic Skyrmion Textures

Majorana bound states are zero-energy states predicted to emerge in topological superconductors and intense efforts seeking a definitive proof of their observation are still ongoing. A standard route to realize them involves antagonistic orders: a superconductor in proximity to a ferromagnet. Here we show this issue can be resolved using antiferromagnetic rather than ferromagnetic order. We propose to use a chain of antiferromagnetic skyrmions, in an otherwise collinear antiferromagnet, coupled to a bulk conventional superconductor as a novel platform capable of supporting Majorana bound states that are robust against disorder. Crucially, the collinear antiferromagnetic region neither suppresses superconductivity nor induces topological superconductivity, thus allowing for Majorana bound states localized at the ends of the chain. Our model introduces a new class of systems where topological superconductivity can be induced by editing antiferromagnetic textures rather than locally tuning material parameters, opening avenues for the conclusive observation of Majorana bound states.Comment: 11 pages, 8 figure

Spin Wave Radiation by a Topological Charge Dipole

The use of spin waves (SWs) as data carriers in spintronic and magnonic logic devices offers operation at low power consumption, free of Joule heating. Nevertheless, the controlled emission and propagation of SWs in magnetic materials remains a significant challenge. Here, we propose that skyrmion–antiskyrmion bilayers form topological charge dipoles and act as efficient sub-100 nm SW emitters when excited by in-plane ac magnetic fields. The propagating SWs have a preferred radiation direction, with clear dipole signatures in their radiation pattern, suggesting that the bilayer forms a SW antenna. Bilayers with the same topological charge radiate SWs with spiral and antispiral spatial profiles, enlarging the class of SW patterns. We demonstrate that the characteristics of the emitted SWs are linked to the topology of the source, allowing for full control of the SW features, including their amplitude, preferred direction of propagation, and wavelength

Tripomastigotes de Trypanosoma cruzi

Galería Fotográfica (Sin Resumen

Determinantes de la calidad docente: programa de asignación de excelencia pedagógica

Los docentes de establecimientos escolares constituyen desde siempre un factor clavedel proceso educativo y de los resultados de aprendizaje de los estudiantes. En razón del rol constitucionalque define al Estado como responsable de la provisión de una educación pública de calidad,es consustancial a su tarea atraer “buenos” profesores, retenerles y motivarles, vía diversos mecanismose incentivos, como también lo es, para el caso chileno, la generación de mecanismos eficientesde evaluación de su desempeño docente. En este marco se encuentra el Programa de Asignaciónde Excelencia Pedagógica (AEP), el cual puede considerarse propiamente como un mecanismo deevaluación e incentivo, pues intenta evaluar algunas dimensiones significativas de la calidad deldocente, premiando los logros con un bono por encima de su salario regular. En razón de la importanciade la calidad docente en los establecimientos subvencionados por el Estado (municipales yparticulares) para el desarrollo del país y la sociedad, este trabajo tiene como objetivo determinarlas características de un docente que ha obtenido la acreditación de calidad de la AEP, a través deun modelo probit condicionado con datos de la Encuesta Longitudinal Docente (ELD), e igualmenteestimar la probabilidad de participar. Se concluye que los factores que explican la probabilidad deser acreditado son: experiencia, condición socio-económica del hogar, nivel de estudios de la madre,estudios, pasantías y capacitaciones, calificación de condiciones de salud, vocación y calificación delprograma AEP, los cuales tienen efectos significativos pero reducido