Les verbalisations ordinaires dans la classe : objets furtifs ou variables encombrantes des sciences du langage ?

Cette contribution tente de mettre en évidence comment, au terme de longues heures consacrées au cours de grammaire, des apprenants ont développé des usages simplifiés ou plus précisément des « catégorisations ordinaires » de la langue. Des exemples de corpus d’apprenants natifs presque adultes, relatifs aux propriétés grammaticales intériorisées puis verbalisées, serviront à illustrer ici comment les 255 « pratiques linguistiques profanes » peuvent contribuer à déconstruire et à reconstruire les réseaux de sens à priori « anti-système ». Ainsi nous verrons mieux, comment coexistent les « savoirs ordinaires et scolaires », migrant d’un champ à l’autre sous la forme d’un continuum. Poser que l’organisation de la langue et de la connaissance constituent un fonctionnement global, amène le didacticien à devoir réduire les obstacles de compréhension de la pratique grammaticale partagée en classe de français, surtout pour des apprenants en difficulté. Dans cette perspective, notre réflexion tend vers une vision élargie des pratiques grammaticales ; en créant une plus grande proximité réflexive entre fonctionnement du langage et de la langue (celui qu’ils connaissent et celui qu’ils rejettent parfois) mais aussi en questionnant les normes et les discours normatifs qui pèsent de tout leur poids sur les représentations grammaticales et dans les procès de communication, dans et hors de la classe

Oralité, littérature et didactique : quelles convergences disciplinaires ?

Cette contribution se propose de réfléchir à la place des corpus de la littérature du début du xxe siècle, celle qui a oralisé la voix narrative, afin de voir si celle-ci est adaptée pour enseigner ou apprendre à prononcer la langue française. On pose que les corpus issus de la littérature parlante constituent une banque de données intéressante en tant qu’outil de médiations culturelle et linguistique, au service des variations de la prononciation. Des exemples illustreront notre propos. Cette perspective interdisciplinaire, entre phonétique, didactique et littérature vise à instaurer un dialogue garant du dépassement de clivage possible entre littérature et langue.This contribution aims to reflect on the place of literature from the early 20th century, that oralised the narrative voice. The question will be asked whether such corpora are adapted to teach or learn to pronounce the French language. It is assumed that corpora from the spoken word literature provide an interesting data bank as a tool for cultural and linguistic mediation, at the service of variations in pronunciation. Examples will illustrate our point. This interdisciplinary perspective, between phonetics, didactics and literature, aims to establish a dialogue that will ensure that the gap between literature and language is overcome

An Extended Theoretical Framework for the Concept of the Derivative

This paper extends the theoretical framework for exploring student understanding of the concept of the derivative, which was developed by Zandieh (2000). We expand upon the con-cept of a physical representation for the derivative by extending Zandieh’s map of the territory to provide higher resolution in regions that are of interest to those operating in a physical context. We also introduce the idea of ”thick ” derivatives, which are ratios of small but not infinitesimal changes, which are practically equivalent to the true derivative. Key words: derivative, theoretical framework, physical, experiment In this theoretical report we extend the theoretical framework for exploring student understand-ing of the concept of the derivative which was developed by Zandieh (2000). We expand upon the concept of a physical representation for the derivative. As with Zandieh’s original framework, this work is not meant to explain how or why students learn as they do, nor to propose a learning trajectory. Rather, this work extends Zandieh’s map of the territory, to provide higher resolution in regions that are of interest to those working with derivatives in a physical context. In addition to focusing on the physical context, we discuss challenges that have arisen in applying Zandieh’

Les dispositifs d'apprentissage collaboratif plurilingues à distance : Nouvelles postures d’enseignement – apprentissage, nouveaux langages. Quel positionnement épistémologique pour la recherche en didactique ?

International audienc

Wnt3 and Wnt3a are required for induction of the mid-diencephalic organizer in the caudal forebrain

Abstract Background A fundamental requirement for development of diverse brain regions is the function of local organizers at morphological boundaries. These organizers are restricted groups of cells that secrete signaling molecules, which in turn regulate the fate of the adjacent neural tissue. The thalamus is located in the caudal diencephalon and is the central relay station between the sense organs and higher brain areas. The mid-diencephalic organizer (MDO) orchestrates the development of the thalamus by releasing secreted signaling molecules such as Shh. Results Here we show that canonical Wnt signaling in the caudal forebrain is required for the formation of the Shh-secreting MD organizer in zebrafish. Wnt signaling induces the MDO in a narrow time window of 4 hours - between 10 and 14 hours post fertilization. Loss of Wnt3 and Wnt3a prevents induction of the MDO, a phenotype also observed upon blockage of canonical Wnt signaling per se. Pharmaceutical activation of the canonical Wnt pathways in Wnt3/Wnt3a compound morphant embryos is able to restore the lack of the MDO. After blockage of Wnt signaling or knock-down of Wnt3/Wnt3a we find an increase of apoptotic cells specifically within the organizer primordium. Consistently, blockage of apoptosis restores the thalamus organizer MDO in Wnt deficient embryos. Conclusion We have identified canonical Wnt signaling as a novel pathway, that is required for proper formation of the MDO and consequently for the development of the major relay station of the brain - the thalamus. We propose that Wnt ligands are necessary to maintain the primordial tissue of the organizer during somitogenesis by suppressing Tp53-mediated apoptosis. </jats:sec

Solution NMR structure of the SH3 domain of human nephrocystin and analysis of a mutation-causing juvenile nephronophthisis.

Human nephrocystin is a protein associated with juvenile NPH, an autosomal recessive, inherited kidney disease responsible for chronic renal failure in children. It contains an SH3 domain involved in signaling pathways controlling cell adhesion and cytoskeleton organization. The solution structure of this domain was solved by triple resonance NMR spectroscopy. Within the core, the structure is similar to those previously reported for other SH3 domains but exhibits a number of specific noncanonical features within the polyproline ligand binding site. Some of the key conserved residues are missing, and the N-Src loop exhibits an unusual twisted geometry, which results in a narrowing of the binding groove. This is induced by the replacement of a conserved Asp, Asn, or Glu residue by a Pro at one side of the N-Src loop. A systematic survey of other SH3 domains also containing a Pro at this position reveals that most of them belong to proteins involved in cell adhesion or motility. A variant of this domain, which carries a point mutation causing NPH, was also analyzed. This change, L180P, although it corresponds to a nonconserved and solvent-exposed position, causes a complete loss of the tertiary structure. Similar effects are also observed with the L180A variant. This could be a context-dependent effect resulting from an interaction between neighboring charged side-chains