De l’intercompréhension comme moteur d’activités en classe

Longtemps, l’enseignement disciplinaire (sciences, mathématiques, histoire…) et l’enseignement des langues sont restés étanches. Depuis quelques années, enseignement de Discipline Non Linguistique (désormais DNL) et classes européennes, régionales ou internationales entrent dans le paysage du collège et du lycée. A l’école primaire, lieu privilégié pour la transdisciplinarité, l’intégration des langues et des disciplines reste encore à pratiquer. La nouvelle loi d’orientation ouvre enfin un nouvel espace scolaire, à cheval sur primaire et collège, qui pourrait également être le lieu d’un tel développement.Nous présenterons une méthode particulière, celle de l’intercompréhension intégrée, qui permet d’aborder langues et disciplines scolaires en les intégrant dans une progression et une méthodologie qui doit autant à la « méthode expérimentale » qu’aux bénéfices du bilinguisme paritaire précoce tel qu’on le connaît dans l’institution, entre français et langue vivante régionale. Le manuel euromania (www.euro-mania.eu) illustre cette méthode d’intégration. Un certain nombre d’expérimentations en classes permet de tirer des conclusions sur son utilisation auprès du public de cycle 3 : quelles compétences sont mises en jeu grâce à l’intégration des langues et des disciplines scolaires, tant du côté de la maîtrise de la langue / des langues, que celui des disciplines, que celui enfin du goût et de la sécurité des apprentissages ? En quoi permet-elle de conforter l’ensemble des compétences de langue ? Comment, enfin, une telle méthode pourrait-elle bénéficier à davantage de classes, de quelle manière, et à quel coût ?Disciplinary teaching - science, mathematics, history - and language teaching have long remained tightly separated. Over the last few years, Content and Language Integrated Learning (=DNL) and European, regional or international classes have been appearing in secondary education. In primary school, although an ideal place for transdisciplinarity, the integration of languages and disciplinary teaching remains to be integrated. At last, the latest Orientation Act opens a new space bridging primary and secondary schools that could provide a frame for such a development. We will introduce a specific method called integrated intercomprehension which makes it possible to combine language and disciplinary teachings and integrate them in an educational progression.The method owes to the “experimental method” as much as to the benefits of early equal-bilingualism as it is known and practiced at school between French and regional languages. The euromania textbook (http://www.euro-mania.eu/) illustrates this integration method. Tests carried out in the context of the classroom allow us to draw a number of conclusions about its usage among primary school children (cycle 3 = 8-10 year olds) : what skills are involved in the integration of language and curricular disciplines, whether through language skills or disciplinary acquisitions or building a taste for and self-confidence in the learning-process? How does this method strengthen all the language skills at the same time? Lastly, how could such a method benefit more classes, in what way, and at what cost

TRÂN Ngọc-Anh, 2018, Taramoin. Tradition orale et tradition écrite à l’école maternelle. Nouvelle-Calédonie, Thio, 1984-1998, Paris, L’Harmattan, collection « Portes Océanes »

Ce récent ouvrage de Ngọc-Anh Trân traite de l’enseignement des populations kanak sur leur propre territoire, français depuis 1853. Le constat de l’échec scolaire assez systématique de cette population force l’auteure à en comprendre les causes, multiples, et à proposer des solutions didactiques et pédagogiques qu’elle-même mettra en place, et que la direction de l’école évaluera. Nous saluons ce livre d’actualité, au moment où se joue une étape très importante du processus politique en Nouve..

Intégrations, « force d’intercourse », identités

Le mode d’enseignement des langues est induit par la représentation que les systèmes d’enseignement ont forgé des langues. Cette représentation est éminemment politique. Parler de langues étrangères revient à rejeter toute altérité au-delà de la sphère de notre propre langue. Or, linguistiquement et socialement, la langue existe, se développe et se définit dans la variation ; par ailleurs, les mobilités nous rappellent que la diversité des langues est une réalité de plus en plus forte et évidente. De ce point de vue, l’enseignement/apprentissage des langues pourrait s’apparenter davantage à une didactisation du contact des langues, prenant en compte leur diversité et leur variabilité. Dans ce cadre, la réalité de l’intercompréhension, devenue depuis quelques temps une méthodologie d’apprentissage, est particulièrement dynamique : véritable « force d’intercourse » selon le mot de Ferdinand de Saussure, elle permet de relier des parlers qui resteraient étanches entre eux.The way languages are taught is a reflexion of the representation at the core of teaching systems. This representation is strikingly political. The notion of a foreign language rejects otherness well beyond the sphere of our own language. However, linguistically and socially, languages exist, develop and are defined through variation. Besides, geographic mobility reminds us that the diversity of languages is an increasingly solid and self-evident reality. Bearing this in mind, teaching/learning languages could be viewed as a didactisation of the interface between languages taking into account their diversity and their changeability. The reality of intercomprehension, which has become a learning methodology, is particularly dynamic in that context. This true “force of intercourse”, in the words of Ferdinand de Saussure, makes it possible to connect dialects that would otherwise remain tightly compartmentalized

Taramoin : tradition orale et tradition écrite à l’école maternelle, Nouvelle-Calédonie, par TRÂN Ngọc-Anh

Présentation d’un travail de recherche sur l’enseignent scolaire de la langue française en Nouvelle-Calédonie Mots clés : École maternelle. Enseignement bi-plurilingue. Français langue de scolarisation. Français langue seconde. Nouvelle-Calédonie.  Taramoin : oral tradition and written tradition at primary school, New Caledonia, by TRÂN Ngọc-Anh Abstract : Presentation of a research on the French language for school teaching in New Caledonia Keywords: Nursery school. Bi-plurilingual education. French language for teaching/learning. French as a second language. New Caledonia.  Taramoin: tradição oral e tradição escrita no ensino fundamental 1, Nova Caledônia, por TRÂN Ngọc-Anh Resumo: Apresentação de uma pesquisa sobre a língua francesa para o ensino escolar na Nova Caledônia. Palavras-chave: Ensino fudamental 1. Educação bi-multilíngue. Língua francesa para ensino / aprendizagem. Francês como segunda língua. Nova Caledônia.  Taramoin: tradición oral y tradición escrita en la escola, Nueva Caledonia, por TRÂN Ngọc-Anh Resumen: Presentación de una investigación sobre el idioma francés para la enseñanza escolar en Nueva Caledonia. Palabras-clave: Escola. Educación bilingüe. Lengua francesa para la enseñanza / aprendizaje. El francés como segunda lengua. Nueva Caledonia

Detection of single DNA molecules by multicolor quantum-dot end-labeling

Observation of DNA–protein interactions by single molecule fluorescence microscopy is usually performed by using fluorescent DNA binding agents. However, such dyes have been shown to induce cleavage of the DNA molecule and perturb its interactions with proteins. A new method for the detection of surface-attached DNA molecules by fluorescence microscopy is introduced in this paper. Biotin- and/or digoxigenin-modified DNA fragments are covalently linked at both extremities of a DNA molecule via sequence-specific hybridization and ligation. After the modified DNA molecules have been stretched on a glass surface, their ends are visualized by multicolor fluorescence microscopy using conjugated quantum dots (QD). We demonstrate that under carefully selected conditions, the position and orientation of individual DNA molecules can be inferred with good efficiency from the QD fluorescence signals alone. This is achieved by selecting QD pairs that have the distance and direction expected for the combed DNA molecules. Direct observation of single DNA molecules in the absence of DNA staining agent opens new possibilities in the fundamental study of DNA–protein interactions. This work also documents new possibilities regarding the use of QD for nucleic acid detection and analysis

Le tuf de Caours (Somme, France) : mise en évidence d'une séquence eemienne et d'un site paléolithique associé

Les nouvelles investigations menées sur les tufs du bassin de la Somme dans le cadre du programme SITEP (CNRS) ont permis de mettre en évidence une formation tufacée reposant sur une nappe alluviale en position de très basse terrasse à Caours (Scardon). La séquence de tufs est séparée de la nappe alluviale périglaciaire sous-jacente par des limons fluviatiles calcaires se terminant par un petit sol de marais coiffé par un liseré de tourbe compactée. La formation tufacée proprement dite comporte essentiellement des faciès palustres à nombreux restes végétaux encroûtés en place et des concrétions travertineuses de type stromatolithes. En direction de la vallée actuelle l’ensemble passe rapidement à des faciès nettement fluviatiles à oncolithes structurés en grandes lentilles à stratifications obliques. La séquence de tuf ainsi que les limons fluviatiles ont livré une abondante faune malacologique qui a permis de décrire une évolution climatique contemporaine des phases initiales d’un interglaciaire, suivi d’un optimum climatique, puis d’une phase de réouverture du milieu exprimant le déclin des conditions tempérées. La base du tuf comporte plusieurs horizons organiques qui ont livré des restes de grands mammifères et de rongeurs contemporains de l’optimum interglaciaire déterminé par les assemblages malacologiques. Dans ces horizons, plusieurs niveaux du Paléolithique moyen ont été découverts en place, en association avec des restes de grande faune interglaciaire fortement fracturés par l’action de l’homme et présentant des traces de découpe. Compte tenu de sa position dans le système de la Somme, des datations par U/Th obtenues sur le tuf (moyenne : ± 120 ka BP) et des conclusions des études bioclimatiques, la séquence de Caours représente le premier témoin de l’interglaciaire Eemien en contexte fluviatile dans le bassin de la Somme. Enfin, les niveaux archéologiques découverts à Caours constituent un exemple unique d’occupation humaine contemporaine du dernier interglaciaire dans la France septentrionale.The new investigation lead on the tufa deposits of the River Somme basin, within the SITEP (CNRS) Program, have allowed the discovery of a new tufa sequence overlying an alluvial formation in low terrace position at Caours (Scardon valley). The tufa sequence is separated from the underlying periglacial alluvial gravels by fluvial calcareous silts overlain by a thin marshy soil and a thin peat layer. The tufa formation is mainly composed by paludal (marshy) soil facies showing numerous in situ incrusted vegetal remains and travertine concretions (stromatoliths). Downslope, looking to the present day valley the whole tufa formation quickly evolves toward typical fluvial facies including oncolithic sands and large scale cross beddings. The tufa sequence and the fluvial silts have provided abundant malacological faunas that have allowed describing a climatic evolution contemporaneous of the initial phases of an interglacial, followed by a climatic optimum and then a decline of temperate conditions. The lower part of the tufa includes several organic horizons that have yielded numerous large mammals and rodent remains contemporaneous of the interglacial optimum previously evidenced by malacology. Within these horizons, several Palaeolithic layers have been discovered in situ in association with interglacial large mammal remains showing evidences of human operation (systematic breaking of long bones and cut marks). Taking into account its relative position within the Somme terraces system, the U/Th ages (average ± 120 ka BP) and the results of the various bioclimatic studies, the Caours sequence represents the first record of the Eemian interglacial in the Somme basin. In addition, the archaeological levels discovered at Caours are a unique example of Human occupation during the Last Interglacial in Northern France

Sliding and jumping of single EcoRV restriction enzymes on non-cognate DNA

The restriction endonuclease EcoRV can rapidly locate a short recognition site within long non-cognate DNA using ‘facilitated diffusion’. This process has long been attributed to a sliding mechanism, in which the enzyme first binds to the DNA via nonspecific interaction and then moves along the DNA by 1D diffusion. Recent studies, however, provided evidence that 3D translocations (hopping/jumping) also help EcoRV to locate its target site. Here we report the first direct observation of sliding and jumping of individual EcoRV molecules along nonspecific DNA. Using fluorescence microscopy, we could distinguish between a slow 1D diffusion of the enzyme and a fast translocation mechanism that was demonstrated to stem from 3D jumps. Salt effects on both sliding and jumping were investigated, and we developed numerical simulations to account for both the jump frequency and the jump length distribution. We deduced from our study the 1D diffusion coefficient of EcoRV, and we estimated the number of jumps occurring during an interaction event with nonspecific DNA. Our results substantiate that sliding alternates with hopping/jumping during the facilitated diffusion of EcoRV and, furthermore, set up a framework for the investigation of target site location by other DNA-binding proteins

Cluster Lenses

Clusters of galaxies are the most recently assembled, massive, bound structures in the Universe. As predicted by General Relativity, given their masses, clusters strongly deform space-time in their vicinity. Clusters act as some of the most powerful gravitational lenses in the Universe. Light rays traversing through clusters from distant sources are hence deflected, and the resulting images of these distant objects therefore appear distorted and magnified. Lensing by clusters occurs in two regimes, each with unique observational signatures. The strong lensing regime is characterized by effects readily seen by eye, namely, the production of giant arcs, multiple-images, and arclets. The weak lensing regime is characterized by small deformations in the shapes of background galaxies only detectable statistically. Cluster lenses have been exploited successfully to address several important current questions in cosmology: (i) the study of the lens(es) - understanding cluster mass distributions and issues pertaining to cluster formation and evolution, as well as constraining the nature of dark matter; (ii) the study of the lensed objects - probing the properties of the background lensed galaxy population - which is statistically at higher redshifts and of lower intrinsic luminosity thus enabling the probing of galaxy formation at the earliest times right up to the Dark Ages; and (iii) the study of the geometry of the Universe - as the strength of lensing depends on the ratios of angular diameter distances between the lens, source and observer, lens deflections are sensitive to the value of cosmological parameters and offer a powerful geometric tool to probe Dark Energy. In this review, we present the basics of cluster lensing and provide a current status report of the field.Comment: About 120 pages - Published in Open Access at: http://www.springerlink.com/content/j183018170485723/ . arXiv admin note: text overlap with arXiv:astro-ph/0504478 and arXiv:1003.3674 by other author

Gravitational Lensing

Gravitational lensing has developed into one of the most powerful tools for the analysis of the dark universe. This review summarises the theory of gravitational lensing, its main current applications and representative results achieved so far. It has two parts. In the first, starting from the equation of geodesic deviation, the equations of thin and extended gravitational lensing are derived. In the second, gravitational lensing by stars and planets, galaxies, galaxy clusters and large-scale structures is discussed and summarised.Comment: Invited review article to appear in Classical and Quantum Gravity, 85 pages, 15 figure

The Lyman Alpha Forest in the Spectra of QSOs

Observations of redshifted Lyman alpha forest absorption in the spectra of quasistellar objects (QSOs) provide a highly sensitive probe of the distribution of gaseous matter in the universe. Over the past two decades optical spectroscopy with large ground-based telescopes, and more recently ultraviolet spectroscopy from space have yielded a wealth of information on what appears to be a gaseous, photoionized intergalactic medium, partly enriched by the products of stellar nucleosynthesis, residing in coherent structures over many hundreds of kiloparsecs. Recent progress with cosmological hydro-simulations based on hierarchical structure formation models has led to important insights into the physical structures giving rise to the forest. If these ideas are correct, a truely inter- and proto-galactic medium [at high redshift (z ~ 3), the main repository of baryons] collapses under the influence of dark matter gravity into flattened or filamentary structures, which are seen in absorption against background QSOs. With decreasing redshift, galaxies forming in the denser regions, may contribute an increasing part of the Lyman alpha absorption cross-section. Comparisons between large data samples from the new generation of telescopes and artificial Lyman alpha forest spectra from cosmological simulations promise to become a useful cosmological tool.Comment: latex plus three postscript figures, uses psfig,sty; Annual Review of Astronomy and Astrophysics 1998, vol. 36 (in press