Le métier d’étudiant : l’entrée dans la vie universitaire

O desenvolvimento do ensino superior é uma questão importante para o desenvolvimento social e para o desenvolvimento de uma sociedade do conhecimento. No Brasil, como na França, o ensino superior passou por um processo de massificação ao longo dos últimos anos e alguns identificam esse processo como democratização. Se a democratização do acesso ao ensino superior é incontestável, não se pode dizer o mesmo sobre a democratização do acesso ao saber, marcado, ao contrário, pela desigualdade. Em verdade, depois que entram na universidade, os estudantes de primeiro ano, cujo nível é muito heterogêneo, enfrentam, frequentemente, grandes dificuldades. Na França, os numerosos fracassos e reorientações que ocorrem no primeiro ano testemunham a dificuldade da passagem do ensino médio para o superior. Com base em pesquisas empíricas, mostrei que os estudantes que não conseguem se afiliar a seu novo universo fracassam, pois o sucesso universitário passa pela aprendizagem de um verdadeiro ofício de estudante. A passagem do ensino médio ao superior é acompanhada por mudanças importantes em sua relação com o saber: as regras não são as mesmas, elas são mais sofisticadas, complexas, simbólicas e devem ser rapidamente assimiladas pelos novos estudantes. Partindo desse contexto, o artigo discute a possibilidade de uma pedagogia da afiliação, e apresenta duas experiências bem-sucedidas: a escrita cotidiana e a aprendizagem da metodologia documental. Essas duas atividades, facilmente realizadas, são eficazes para fazer com que os novos estudantes entrem em seu novo mundo: o mundo das ideias.The development of higher education is a major asset for social development and for that of a society of knowledge, all over the world. In Brazil, as in France, a phenomenon of mass enrolment at university has occurred over the past few years. For some, it is a sign of the democratisation of higher education. The democratisation is real regarding enrolling at university, but access to knowledge is, conversely, marked by inequality. Indeed, first year students have extremely different levels of competence, and after they have enrolled at university, freshmen often experience serious difficulties. In France, students fail or are reoriented massively during their first year at university. This is an indication of how difficult the passage from high school to university is. The author rests his studies on empirical research, and demonstrates that the students who have not managed to affiliate to their new world fail or drop out, as success in higher education implies learning the job of being a student. The passage from high school to university comes with substantial changes in the students’ relations to knowledge. The rules differ, they are more sophisticated, more complex and more symbolic and have to be rapidly assimilated by the new students. The author raises the question of a pedagogy of affiliation, illustrating his purpose with two examples of successful experiments that he carried out: having the students write a diary on a daily basis on the one hand, having them learn the methodology of library work on the other hand. These two activities are easily carried out and are efficient in helping freshmen successfully enter their new world: the world of ideas.Résumé Le développement de l’enseignement supérieur est, partout dans le monde, un enjeu pour le développement social et pour celui d’une société de la connaissance. Au Brésil comme en France, l’enseignement supérieur a connu un phénomène de massification au cours des dernières années, certains parlant même de démocratisation. Si la démocratisation à l’entrée de l’enseignement supérieur est incontestable, il n’en est pas de même pour la démocratisation de l’accès au savoir, marqué au contraire par l’inégalité. En effet, une fois entrés à l’université, les étudiants de première année, dont le niveau est très hétérogène, connaissent souvent de grandes difficultés. En France, les nombreux échecs et les réorientations en première année témoignent de la difficulté du passage entre enseignement secondaire et enseignement supérieur. L’auteur, s’appuyant sur des recherches empiriques, montre que les étudiants qui ne parviennent pas à s’affilier à leur nouvel univers échouent, la réussite universitaire passant par l’apprentissage d’un véritable métier d’étudiant. Le passage du secondaire au supérieur s’accompagne de changements importants dans leur relation au savoir: les règles ne sont plus les mêmes, elles sont plus sophistiquées, plus complexes, plus symboliques, et doivent être rapidement assimilées par les nouveaux étudiants. Enfin, l’auteur s’interroge sur la possibilité d’une pédagogie de l’affiliation, et donne deux exemples qu’il a lui-même expérimentés avec succès : l’écriture quotidienne, d’une part, l’apprentissage de la méthodologie documentaire, d’autre part. Ces deux activités, faciles à mettre en œuvre, sont efficaces pour faire entrer les nouveaux étudiants dans leur nouvel monde: celui des idées

Etat des savoirs sur les relations entre les étudiants, les enseignants et les IATOSS dans les établissements d\u27enseignement supérieur

Cette étude a pour objet d\u27établir un état des savoirs sur les relations entre les étudiants, les enseignants et les personnels administratifs (IATOSS) dans les établissements d\u27enseignement supérieur. Elle présente tout d\u27abord un état des savoirs en la matière, s\u27appuyant sur des publications et documents relatifs aux aspects relationnels dans l\u27enseignement supérieur en France. Elle aborde ensuite les conséquences que la massification de l\u27université française a engendrée, à partir des années 1980, sur le contexte humain de l\u27université. Puis elle expose successivement les points de vue des étudiants (y compris les étrangers) sur leurs relations avec les enseignants ; les représentations des enseignants vis-à-vis de leur travail et les perceptions qu\u27ils ont des étudiants ; la relation entre les étudiants eux-mêmes, et le rôle des personnels IATOSS

Avec Alain Epelboin et Jean-Charles Coulon. D’hier à aujourd’hui : enquêtes sur les talismans et les manuscrits de sciences occultes en Islam

Contrairement à la théologie ou la philosophie, les sciences occultes ont souvent été abordées avec dédain et mépris dans la tradition savante orientaliste au xixe siècle et au début du xxe. Pourtant, ces sciences étaient très importantes, notamment parmi les élites, comme en témoigne le mécénat exercé par des califes et des souverains dès le viiie siècle. Ce succès a persisté aux époques mameloukes et ottomanes, qui nous ont légué un grand nombre de manuscrits. L’apparition de la lithographie a cependant permis une plus large diffusion de ces savoirs, et, par exemple, le Shams al-maʿārif (Le Soleil des connaissances) attribué à al-Būnī (m. 1225 ou 1232) est devenu un véritable manuel indispensable à tous les praticiens. Il s’agit d’un des ouvrages fondamentaux des fabricants de talismans en Afrique de l’Ouest. Une enquête inaugurée par la découverte d’amulettes et d’écrits talismaniques dans une décharge à ordures de Dakar retrace les origines mystérieuses de ces talismans pour mettre au jour leurs hypotextes, issus de manuscrits de sciences occultes médiévaux. Un double regard sur ces objets-textes énigmatiques, celui de l’ethnologue Alain Epelboin et de l’historien Jean-Charles Coulon, révèle les liens qui se tissent entre l’art des écrits talismaniques, l’islam et certains savoirs ésotériques plus anciens

Cell proliferation and migration during early development of a symbiotic scleractinian coral

In scleractinian reef-building corals, patterns of cell self-renewal, migration and death remain virtually unknown, limiting our understanding of cellular mechanisms underlying initiation of calcification, and ontogenesis of the endosymbiotic dinoflagellate relationship. In this study, we pulse-labelled the coral Stylophora pistillata for 24 h with BrdU at four life stages (planula, early metamorphosis, primary polyp and adult colony) to investigate coral and endosymbiont cell proliferation during development, while simultaneously recording TUNEL-positive (i.e. apoptotic) nuclei. In the primary polyp, the fate of BrdU-labelled cells was tracked during a 3-day chase. The pharynx and gastrodermis were identified as the most proliferative tissues in the developing polyp, and BrdU-labelled cells accumulated in the surface pseudostratified epithelium and the skeletogenic calicodermis during the chase, revealing cell migration to these epithelia. Surprisingly, the lowest cell turnover was recorded in the calicodermis at all stages, despite active, ongoing skeletal deposition. In dinoflagellate symbionts, DNA synthesis was systematically higher than coral host gastrodermis, especially in planula and early metamorphosis. The symbiont to host cell ratio remained constant, however, indicating successive post-mitotic control mechanisms by the host of its dinoflagellate density in early life stages, increasingly shifting to apoptosis in the growing primary polyp

Do lambs perceive regular human stroking as pleasant? Behavior and heart rate variability analyses

Stroking by humans is beneficial to the human-animal relationship and improves welfare in many species that express intraspecific allogrooming, but very few studies have looked at species like sheep that do not express such contact except around parturition. This study investigated the way lambs perceive regular human tactile contact using behavioral and physiological responses. Twenty-four lambs were reared and bucket-fed in groups of four. All were stroked daily by their familiar caregiver. At 8 weeks of age, the lambs were individually tested in their home pen but in a 1×1m open-barred pen after a 15h period of habituation to physical separation from peers while remaining in visual and auditory contact. Half of the lambs received stroking by their caregiver for 8min and half were exposed to their caregiver’s immobile presence. Heart rate and heart rate variability were recorded and analyzed by 2-min slots over the same interval based on three measures: mean heart rate value (HR), root mean square of successive differences (RMSSD) and standard deviation of all intervals measured between consecutive sinus beats (SDNN). Behavioral responses (ear postures of the lamb and time spent in contact with the familiar caregiver, on the knees of the familiar caregiver, and moving) were recorded throughout the test. Lamb HR decreased continuously while in the presence of their caregiver. Lambs being stroked showed slower HR and higher RMSSD which reflected positive emotional states compared to lambs left unstroked. All behavioral variables were highly correlated with the main component axis of the PCA analyses: the more the animals stayed in contact with their caregiver, the less they moved and the more their ears were hanging. This first component clearly differentiates lambs being stroked or not. Behavioral and physiological observations support the hypothesis that gentle physical contact with the caregiver is perceived positively by lambs

Chemical Analysis of Cellular and Extracellular Carbohydrates of a Biofilm-Forming Strain Pseudomonas aeruginosa PA14

Background: Pseudomonas aeruginosa is a Gram-negative bacterium and an opportunistic pathogen, which causes persisting life-threatening infections in cystic fibrosis (CF) patients. Biofilm mode of growth facilitates its survival in a variety of environments. Most P. aeruginosa isolates, including the non-mucoid laboratory strain PA14, are able to form a thick pellicle, which results in a surface-associated biofilm at the air-liquid (A\ufffdL) interface in standing liquid cultures. Exopolysaccharides (EPS) are considered as key components in the formation of this biofilm pellicle. In the non-mucoid P. aeruginosa strain PA14, the \ufffd\ufffdscaffolding\ufffd\ufffd polysaccharides of the biofilm matrix, and the molecules responsible for the structural integrity of rigid A\ufffdL biofilm have not been identified. Moreover, the role of LPS in this process is unclear, and the chemical structure of the LPS O-antigen of PA14 has not yet been elucidated. Principal Findings: In the present work we carried out a systematic analysis of cellular and extracellular (EC) carbohydrates of P. aeruginosa PA14. We also elucidated the chemical structure of the LPS O-antigen by chemical methods and 2-D NMR spectroscopy. Our results showed that it is composed of linear trisaccharide repeating units, identical to those described for P. aeruginosa Lanyi type O:2a,c (Lanyi-Bergman O-serogroup 10a, 10c; IATS serotype 19) and having the following structure: -4)-a-L-GalNAcA-(1\ufffd3)-a-D-QuiNAc-(1\ufffd3)- a-L-Rha-(1-. Furthermore, an EC O-antigen polysaccharide (EC O-PS) and the glycerol-phosphorylated cyclic b-(1,3)-glucans were identified in the culture supernatant of PA14, grown statically in minimal medium. Finally, the extracellular matrix of the thick biofilm formed at the A-L interface contained, in addition to eDNA, important quantities (at least ,20% of dry weight) of LPS-like material. Conclusions: We characterized the chemical structure of the LPS O-antigen and showed that the O-antigen polysaccharide is an abundant extracellular carbohydrate of PA14. We present evidence that LPS-like material is found as a component of a biofilm matrix of P. aeruginosa.Peer reviewed: YesNRC publication: Ye

Landscape homogenization due to agricultural intensification disrupts the relationship between reproductive success and main prey abundance in an avian predator

Selecting high-quality habitat and the optimal time to reproduce can increase individual fitness and is a strong evolutionary factor shaping animal populations. However, few studies have investigated the interplay between land cover heterogeneity, limitation in food resources, individual quality and spatial variation in fitness parameters. Here, we explore how individuals of different quality respond to possible mismatches between a cue for prey availability (land cover heterogeneity) and the actual fluctuating prey abundance.Peer reviewe

Low loss coatings for the VIRGO large mirrors

présentée par L. PinardThe goal of the VIRGO program is to build a giant Michelson type interferometer (3 kilometer long arms) to detect gravitational waves. Large optical components (350 mm in diameter), having extremely low loss at 1064 nm, are needed. Today, the Ion beam Sputtering is the only deposition technique able to produce optical components with such performances. Consequently, a large ion beam sputtering deposition system was built to coat large optics up to 700 mm in diameter. The performances of this coater are described in term of layer uniformity on large scale and optical losses (absorption and scattering characterization). The VIRGO interferometer needs six main mirrors. The first set was ready in June 2002 and its installation is in progress on the VIRGO site (Italy). The optical performances of this first set are discussed. The requirements at 1064 nm are all satisfied. Indeed, the absorption level is close to 1 ppm (part per million), the scattering is lower than 5 ppm and the R.M.S. wavefront of these optics is lower than 8 nm on 150 mm in diameter. Finally, some solutions are proposed to further improve these performances, especially the absorption level (lower than 0.1 ppm) and the mechanical quality factor Q of the mirrors (thermal noise reduction)