Distributed Teaching

The central phenomenon that this entry seeks to explore is that people with the job title of “teacher” are almost never the only teachers in a learning transaction, and autodidacts are almost never solely responsible for their own learning. As well as designated teachers and students, text book authors, editors, illustrators, exam boards, curriculum designers, governments, timetablers, classroom designers, architects, learning management system managers, counselors, career advisors, makers of YouTube videos, discussion forums, friends, family, and very many other individuals and groups can and do play an active and often highly significant teaching role in guiding, supporting, and managing the learning process. Online learning, especially when it involves a team of specialists working on a course, makes the distributed nature of the process very visible, and the relative autonomy of online learners makes it more likely that they will seek additional or alternative supports for learning, but virtually all conventional in-person teaching involves multiple teachers too, from peers to textbook authors and, most especially, the learners themselves

Transactional distance in a blended learning environment

This paper presents a case study that describes and discusses the problems encountered during the design and implementation of a blended learning course, largely taught online through a web-based learning environment. Based on Moore's theory of transactional distance, the course was explicitly designed to have dialogue at its heart. However, the reality of systemic behaviours caused by delivering such a course within a group of conventional further and higher educational institutions has led to an entirely unanticipated reversion to structure, with unpleasant consequences for both quality and quantity of dialogue. The paper looks at some of the reasons for this drift, and suggests that some of the disappointing results (in particular in terms of the quality of the students' experience and associated poor retention) can be attributed to the lack of dialogue, and consequent increase in transactional distance. It concludes with a description and evaluation of steps currently being taken to correct this behaviour

Cálculo del centro de gravedad con Arduino para Android

Se presenta el diseño y la implementación de un sistema para medir el centro de gravedad de drones utilizando Arduino y visualizando los datos en un dispositivo con Android. Medir el centro de gravedad nos permitirá llevar un control de cómo se distribuye la carga en un dron, y por lo tanto, nos puede ayudar a identificar errores que se pueden producir en este a causa de una mala distribución e incluso problemas con la sujeción de la carga.This Article describes how to create a system to measure the center of gravity of a dron using Arduino and Android. Measure the center of gravity allow us to monitor how the load of a dron is distributed. Having knowledge about the center of gravity can help us to identify some errors that could happen (before they happen) and even it can help us to identify problems in the fastening.Es presenta el disseny i la implementació d'un sistema per mesurar el centre de gravetat de drons utilitzant Arduino i visualitzant les dades amb un dispositiu amb Android. Mesurar el centre de gravetat ens permet portar un control sobre com es troba distribuida la càrrega en un dron, i per tant, ens pot ajudar a identificar els errors que es poden produir a causa d'una mala distribució i fins i tot, problemes en la subjecció de la càrrega

Integrating GHG dynamics in biomass-based products LCA

International audienc

Quelques faits concernant les organismes génétiquement modifiés produits et exploités jusqu'ici

International audienceEssayer « d’aller plus nettement au fond des choses, de clarifier tenants et aboutissants, et d’inciter au débat », disait Patrick Legrand dans son édito du n° 531. L’article qui suit s’inscrit parfaitement dans cette nouvelle ligne éditoriale du Courrier. À première vue, il est vrai, cette compilation de faits d’origines diverses et d’apparence hétéroclite pourrait laisser supposer l’inverse. C’est pourtant, justement, par ce rapprochement de faits scientifiques, technologiques, industriels, juridiques, sociaux que se dessinent sous nos yeux les contours d’un objet socio-technique complexe, les OGM. D’aucuns trouveront cette compilation incomplète et subjective, certes ; mais entre une approche unilatérale, même exhaustive et objective, et celle proposée ici, même imparfaite, Le Courrier de l’Environnement de l’INRA préférera toujours celle qui met la science dans la société

Elastic energy of polyhedral bilayer vesicles

In recent experiments [M. Dubois, B. Dem\'e, T. Gulik-Krzywicki, J.-C. Dedieu, C. Vautrin, S. D\'esert, E. Perez, and T. Zemb, Nature (London) Vol. 411, 672 (2001)] the spontaneous formation of hollow bilayer vesicles with polyhedral symmetry has been observed. On the basis of the experimental phenomenology it was suggested [M. Dubois, V. Lizunov, A. Meister, T. Gulik-Krzywicki, J. M. Verbavatz, E. Perez, J. Zimmerberg, and T. Zemb, Proc. Natl. Acad. Sci. U.S.A. Vol. 101, 15082 (2004)] that the mechanism for the formation of bilayer polyhedra is minimization of elastic bending energy. Motivated by these experiments, we study the elastic bending energy of polyhedral bilayer vesicles. In agreement with experiments, and provided that excess amphiphiles exhibiting spontaneous curvature are present in sufficient quantity, we find that polyhedral bilayer vesicles can indeed be energetically favorable compared to spherical bilayer vesicles. Consistent with experimental observations we also find that the bending energy associated with the vertices of bilayer polyhedra can be locally reduced through the formation of pores. However, the stabilization of polyhedral bilayer vesicles over spherical bilayer vesicles relies crucially on molecular segregation of excess amphiphiles along the ridges rather than the vertices of bilayer polyhedra. Furthermore, our analysis implies that, contrary to what has been suggested on the basis of experiments, the icosahedron does not minimize elastic bending energy among arbitrary polyhedral shapes and sizes. Instead, we find that, for large polyhedron sizes, the snub dodecahedron and the snub cube both have lower total bending energies than the icosahedron