27 research outputs found
Un village de montagne modélisé à l'école
L'enfant est mis en situation-problème: comment représenter l'espace de son village le plus simplement, afin que chacun comprenne l'organisation de cet espace, notamment le maître, nouvellement arrivé. L'observation de ce milieu, connu par l'élève et qui correspond à son espace de vie, est le point de départ du travail (classe à 3 niveaux à l'école de Saint-Dalmas-de-Tende, Alpes-Maritimes)
Phage T5 straight tail fiber is a multifunctional protein acting as a tape measure and carrying fusogenic and muralytic activities
We report a bioinformatic and functional characterization of Pb2, a 121-kDa multimeric protein that forms phage T5 straight fiber and is implicated in DNA transfer into the host. Pb2 was predicted to consist of three domains. Region I (residues 1-1030) was mainly organized in coiled coil and shared features of tape measure proteins. Region II (residues 1030-1076) contained two alpha-helical transmembrane segments. Region III (residues 1135-1148) included a metallopeptidase motif. A truncated version of Pb2 (Pb2-Cterm, residues 964-1148) was expressed and purified. Pb2-Cterm shared common features with fusogenic membrane polypeptides. It formed oligomeric structures and inserted into liposomes triggering their fusion. Pb2-Cterm caused beta-galactosidase release from Escherichia coli cells and in vitro peptidoglycan hydrolysis. Based on these multifunctional properties, we propose that binding of phage T5 to its receptor triggers large conformational changes in Pb2. The coiled coil region would serve as a sensor for triggering the opening of the head-tail connector. The C-terminal region would gain access to the host envelope, permitting the local degradation of the peptidoglycan and the formation of the DNA pore by fusion of the two membranes
The rose of the Sainte-Chapelle in Paris: sophisticated stained glasses for late medieval painters
The restoration of the rose (15th century) of the Sainte-Chapelle in Paris, France, offered a unique opportunity to investigate the color and chemical composition of these emblematic medieval French stained glasses with non-destructive analyses. The obtained results are aimed at complementing the knowledge from art historians and thus together trying to compensate for the total absence of archives on the construction of the rose. Comparison with the glasses of the nave (13th century) reveals an important evolution of the aesthetics based on new types of glasses: new colors and extensive use of flashed glass. The systematic study of the chemical composition of both sides of each glass piece revealed that about half of the studied glasses were flashed. For non-flashed glasses, this comparison allowed evaluating the influence of glass surface weathering, although very moderate, on the composition variability. In light of the variability criteria, the multivariate analysis of the chemical composition allowed inferring that most glasses originate from the same production glasshouse. The new colors result from the original composition of flashed glass, allowing superimposing otherwise incompatible redox states of the coloring transition elements. The comparison with the glasses of the nave reveals the glass technology evolution that occurred over two centuries and allowed the production of new glasses for the medieval glaziers at the eve of the Parisian Renaissance
The rose of the Sainte-Chapelle in Paris: sophisticated stained glasses for late medieval painters
The restoration of the rose (15th century) of the Sainte-Chapelle in Paris, France, offered a unique opportunity to investigate the color and chemical composition of these emblematic medieval French stained glasses with non-destructive analyses. The obtained results are aimed at complementing the knowledge from art historians and thus together trying to compensate for the total absence of archives on the construction of the rose. Comparison with the glasses of the nave (13th century) reveals an important evolution of the aesthetics based on new types of glasses: new colors and extensive use of flashed glass. The systematic study of the chemical composition of both sides of each glass piece revealed that about half of the studied glasses were flashed. For non-flashed glasses, this comparison allowed evaluating the influence of glass surface weathering, although very moderate, on the composition variability. In light of the variability criteria, the multivariate analysis of the chemical composition allowed inferring that most glasses originate from the same production glasshouse. The new colors result from the original composition of flashed glass, allowing superimposing otherwise incompatible redox states of the coloring transition elements. The comparison with the glasses of the nave reveals the glass technology evolution that occurred over two centuries and allowed the production of new glasses for the medieval glaziers at the eve of the Parisian Renaissance
Un village de montagne modélisé à l’école
Children are confronted to the problem of how to represent their village in the simplest possible way so as to help anybody understand its spatial organisation, notably the teacher, who is a newcomer to the area. The starting point of the exercise consists in the pupils of the three age-group class of Saint-Dalmas-de-Tende (Alpes-Maritimes) observing this environment which corresponds to their own living space.L’enfant est mis en situation-problème : comment reprĂ©senter l’espace de son village le plus simplement, afin que chacun comprenne l’organisation de cet espace, notamment le maĂ®tre, nouvellement arrivĂ©. L’observation de ce milieu, connu par l’élève et qui correspond Ă son espace de vie, est le point de dĂ©part du travail (classe Ă 3 niveaux Ă l’école de Saint-Dalmas-de-Tende, Alpes-Maritimes).Al alumno se le plantea una situaciĂłn-problema : Âż cĂłmo representar el espacio de su pueblo del modo más sencillo para que todos comprendan la organizaciĂłn de dicho espacio, especialmente el maestro, reciĂ©n llegado ? La observaciĂłn de este medio, conocido por el alumno y que corresponde a su espacio de vida, es el punto de partida del trabajo (clase de 3 niveles en la escuela de Saint-Dalmas-de-Tende, Alpes MarĂtimos).Boulanger Claudine, Battu Serge. Un village de montagne modĂ©lisĂ© Ă l’école. In: Mappemonde, 1995/3. pp. 40-42
La peinture sur verre Ă Florence au temps d'Antoine de Pise
étude des grands chantiers de peinture sur verre à Florence à la fin du 14e siècl
La peinture sur verre Ă Florence au temps d'Antoine de Pise
étude des grands chantiers de peinture sur verre à Florence à la fin du 14e siècl
La modélisation graphique, aide à l’apprentissage de l’espace géographique à l’école élémentaire (cycle III)
It is interesting, in didactic terms, to transform scholarly knowledge that of theoretical and quantitative geography at academic level into the sort of knowledge which is accessible to elementary school pupils. 4th and 5th-year primary school pupils are capable of modelling a city or a dĂ©partement (Alpes Maritimes) : because the approach is completely different even pupils who have difficulties in writing can achieve this. The experiment has been carried out with two 4th-year groups, one of them with average, the other with below-average achievements in class, both from deprived inner city areas.Transposer le savoir savant, universitaire, oĂą la gĂ©ographie thĂ©orique et quantitative se pratique Ă un niveau Ă©levĂ©, en un savoir accessible aux Ă©lèves de l’école Ă©lĂ©mentaire, prĂ©sente un grand intĂ©rĂŞt didactique. La modĂ©lisation d’une ville ou d’un dĂ©partement, ici : les Alpes-Maritimes, est rĂ©alisable par des Ă©lèves de cours moyen, y compris par des Ă©lèves qui ont des difficultĂ©s en expression Ă©crite, puisque la dĂ©marche est tout autre. L’expĂ©rience concerne deux classes de CM1, l’une de niveau moyen, l’autre de niveau faible dans un quartier dĂ©favorisĂ©.Pasar del saber erudito, universitario, en el cual la geografĂa teĂłrica y cuantitativa se practica al nivel más elevado, a un saber accesible a los alumnos de EGB, presenta un gran interĂ©s didáctico. La modelizaciĂłn de una ciudad o un departamento (Los Alpes MarĂtimos) es realizable por alumnos del ciclo medio de EGB, incluso por alumnos con dificultades de expresiĂłn escrita, ya que el enfoque es totalmente distinto. La experiencia corresponde a dos clases de ciclo medio de EGB, en un barrio pobre : una alcanza un nivel mediano, otra un nivel más flojo.Boulanger Claudine, Arbona Pascale, Gringore Carole. La modĂ©lisation graphique, aide Ă l’apprentissage de l’espace gĂ©ographique Ă l’école Ă©lĂ©mentaire (cycle III). In: Mappemonde, 1994/2. pp. 9-14
Les controverses du traitement hormonal de substitution en 2004 (enquête auprès de femmes ménopausées de Poitiers et ses environs afin d'évaluer l'impact des études américaine et anglaise)
POITIERS-BU MĂ©decine pharmacie (861942103) / SudocSudocFranceF
A Multi-Actor Partnership and a Multidisciplinary Approach to Innovate Forest Planting Practices
La plantation forestière est un outil important pour l’adaptation des forêts aux changements globaux. Les échecs parfois récurrents dans certains contextes, les coûts associés à la plantation, la pénibilité du travail pour les ouvriers forestiers ainsi que les impacts environnementaux parfois négatifs sont autant de facteurs qui freinent le recours à la plantation et peuvent ainsi limiter la capacité d’adaptation des forêts. Un ensemble de travaux ont été menés pour répondre aux besoins en innovation technique sur les méthodes de plantation exprimés par les praticiens. Ces travaux portent sur le processus d’innovation en sylviculture et sur l’amélioration technique des méthodes de plantation. L’analyse du processus d’innovation indique une faiblesse des réseaux sociotechniques associée à un mauvais partage des connaissances entre acteurs, et une réticence à l’investissement dans du nouveau matériel, dans un contexte économique perçu comme incertain. Ces observations suggèrent qu’un des leviers possibles serait une meilleure mise en réseau des acteurs, à travers différents liens fonctionnels: partage d’information, échanges de services, construction de partenariats économiques. Des exemples de méthodes innovantes pour réaliser chacune des différentes étapes de l’itinéraire de plantation (préparation du site, plantation, entretiens), répondant aux besoins d’innovation technique exprimés par les praticiens, sont ensuite présentés.Forest plantation is a major tool to adapt forest ecosystems to global change. Plantation failure that recurrently occur in some contexts, associated financial costs, the hard and repetitive nature of tree planting, and potential negative environmental impacts of forest plantation strongly reduce the use of plantation to regenerate forest stands. A series of studies was conducted to address the need for forest practitioners to innovate. The studies focus on the innovation process in silviculture, and on the technical improvement of plantation methods. The analysis of the innovation process highlights the weaknesses of the sociotechnical networks, in relationship with poor knowledge exchange practices, and strong reluctance to invest in new equipment in an uncertain future context. Developing stronger sociotechnical networks, based on information, service and financial flows, is a key to the development and diffusion of new silvicultural methods. Finally, examples of new methods, to execute the successive steps of forest planting (site preparation, planting, cleaning operations), addressing the expectations of forest practitioners, are presented