Les effets des interventions auprès des personnes silencieuses dans les groupes

Un phénomène fréquemment observable dans les groupes est la distribution inégale du temps de parole entre les membres. En écho à cette situation, plusieurs stratégies d'intervention sont proposées pour inciter les personnes silencieuses à affirmer leur position. Ces stratégies sont en accord avec les représentations généralement négatives qu'on se fait du silence dans les milieux des services sociaux et de l'éducation. Après une description de quatre représentations dominantes, l'article montre que le silence n'a pas à être réduit à un mode atrophié ou dévié d'expression, c'est-à-dire un mode à corriger à tout prix. Il montre aussi que les interventions où l'on cherche à faire parler les personnes silencieuses, si bien intentionnées soient-elles, ont parfois un effet contraire à celui recherché.A phenomenon which occurs commonly within groups is the uneven distribution of speach time between members. In answer to this situation, several intervention strategies are proposed in order to incite quiet individuals to assert their opinion. These strategies agree with the negative representation of silence which is common in the fields of education and social services. After describing four major representations of silence, this article shows that silence does not have to be assimilated with a weakened or otherwise deviated means of expression, i.e. something to be corrected at any cost. It also shows that interventions aimed at forcing quiet individuals to speak, as well-meaning as they maybe, sometimes yield results contrary to what was intended

Nanostructured polymers for photonics

We review recent progress in the development of polymer nanostructured materials with periodic structures and compositions having applications in photonics and optical data storage. This review provides a brief description of the microfabrication and self-assembly methods used for the production of polymer materials with periodic structures, and highlights the properties and applications of photonic materials derived from block copolymers, colloid crystals, and microfabricated polymers. We conclude with a summary of current and future research efforts and opportunities in the development of polymer materials for photonic applications

Versatile volumetric additive manufacturing with 3D ray tracing

Tomographic volumetric additive manufacturing (VAM) is an optical 3D printing technique where an object is formed by photopolymerizing resin via tomographic projections. Currently, these projections are calculated using the Radon transform from computed tomography but it ignores two fundamental properties of real optical projection systems: finite etendue and non-telecentricity. In this work, we introduce 3D ray tracing as a new method of computing projections in tomographic VAM and demonstrate high fidelity printing in non-telecentric and higher etendue systems, leading to a 3X increase in vertical build volume than the standard Radon method. The method introduced here expands the possible tomographic VAM printing configurations, enabling faster, cheaper, and higher fidelity printing.Comment: 16 pages, 8 figure

Organizational values and job satisfaction: the role of the professionnal environment

info:eu-repo/semantics/publishe

Superparamagnetic microspheres with controlled macroporosity generated in microfluidic devices

A microfluidic approach to preparing superparamagnetic microspheres with tunable porosity is described. In this method, droplets consisting of iron oxide nanoparticles, a functional polymer and solvent are formed in a microfluidic channel. The droplets are subsequently collected in solutions of sodium dodecyl sulfate (SDS) where the solvent is left to diffuse out of the droplet phase. By adjusting the concentration of the SDS and the polarity of the solvent of the dispersed phase, the porosity of the microparticles is controlled from non porous to porous structure. The formation of the pores is shown to depend on the rate at which solvent diffuses out of the droplet phase and the availability of SDS to adsorb at the droplet interface.Peer reviewed: YesNRC publication: Ye

Nanobeads highly loaded with superparamagnetic nanoparticles prepared by emulsification and seeded-emulsion polymerization

Functional superparamagnetic colloids possessing high saturation magnetization are prepared by emulsification of superparamagnetic nanoparticles (SPM NPs) and heterogeneous polymerization. The colloids consist of a core of densely packed NPs encapsulated within a thin polymer shell. The cores are made by emulsifying SPM NPs and toluene into an aqueous surfactant solution, and subsequently condensing the emulsion droplets by removal of the solvent generating clusters of SPM NPs. By tuning the emulsification condition, this approach allows for control over the size of the clusters from approximately 40 to 200 nm. The polymer shells encapsulating the clusters are made by using seeded-emulsion polymerization concepts. Control over the thickness of the shell and the incorporation of functional groups to the colloid is achieved. Characterization by thermogravimetric analysis (TGA) and magnetometry shows that these colloids have 66 wt % of magnetic material and saturation magnetization of 47 emu/g, confirming that this route generates colloids with a high loading of SPM NPs and high saturation magnetizations.Peer reviewed: YesNRC publication: Ye