Les trafiquants de rêves: pratiques artisitques en milieu carcéral

Ce travail de recherche analyse, à partir d’un modèle d’entretien compréhensif et d’une recherche performative, la représentation des pratiques artistiques chez les acteurs du milieu carcéral dans un dispositif d’enfermement particulier qui est celui de la détention avant jugement

Evaluation of a permeability-porosity relationship in a low permeability creeping material using a single transient test

A method is presented for the evaluation of the permeability-porosity relationship in a low-permeability porous material using the results of a single transient test. This method accounts for both elastic and non-elastic deformations of the sample during the test and is applied to a hardened class G oil well cement paste. An initial hydrostatic undrained loading is applied to the sample. The generated excess pore pressure is then released at one end of the sample while monitoring the pore pressure at the other end and the radial strain in the middle of the sample during the dissipation of the pore pressure. These measurements are back analysed to evaluate the permeability and its evolution with porosity change. The effect of creep of the sample during the test on the measured pore pressure and volume change is taken into account in the analysis. This approach permits to calibrate a power law permeability-porosity relationship for the tested hardened cement paste. The porosity sensitivity exponent of the power-law is evaluated equal to 11 and is shown to be mostly independent of the stress level and of the creep strains

Un regard nouveau sur la diglossie français-créole. Esquisse d’une approche écosystémique des langues

Il semble important de rénover la vision traditionnelle de la diglossie aux Antilles en tenant compte à la fois des données écosystémiques et des aspirations identitaires. C’est à ce prix que, scientifiquement informées, l’ensemble des communautés créolophones pourra remplacer le duel idéologique créole-français par un duo fonctionnel, fonctionnant donc sur une base de coopération, et définissant ce qu’il est convenu d’appeler un colinguisme.It seems important to renew the traditional vision of diglossia in the Antilles by taking into account both ecosystemic data and identity aspirations. This is the price that, scientifically informed, all Creole-speaking communities will be able to replace the ideological Creole-French duel by a functional duo, thus functioning on a basis of cooperation, and defining what is known as colingualism

La Créolité, vingt ans après

About twenty years after the publication of the essay In Praise of Creoleness, it was necessary to come back to the concept that constitutes its main theme, even if it meant revisiting, or even revising, in a self-critical perspective, some of its ideological and political implications. Beyond the semantic value of the word "creole" and analysis of the modes and processes of linguistic creolization, this article aims at containing the various potential risks, among which, for instance, that of communitarianism which may follow from an unduly essentialist sense of the term, the sharing of ancestors then appearing as both the optimal definition of Creoleness and the antidote to the communitarian reduction

LA ELECCIÓN DE LA LENGUA Y LA CREATIVIDAD LITERARIA EN AIMÉ CESAIRE

Otros caribes: de las Antillas al continente (sudamérica, centroamérica y norteamérica

Un botánico en el matadero: Auguste de Saint-Hilaire en la Banda Oriental

Between 1816 and 1822 the French botanist Auguste de Saint-Hilaire travelled widely in Brazil, closely studying the tropical flora, and, at the same time, taking particular interest in the social and cultural situations of local populations. He thus collected a vast number of observations which he later developed into detailed travel narratives. On the last and longest of his journeys, he reached the province of Rio Grande do Sul, and the territory known as the “Banda Oriental” (today Uruguay). In both these regions, of a more temperate climate, he censured the predomi-nance of a cattle-bound economy and the widespread consumption of beef, and analysed the psy-chological effects of an excessive familiarity with the spectacle of cattle-slaughter. Certain com-ments in his travel journal on particularly colourful scenes denote a marked cultural breach, but they also allow one to glimpse, behind the overt censuring, rejection and indeed horror, a hidden fascination, which would somehow be responding to the ancient and complex symbolic relationship between human beings and animal flesh.Entre los años 1816 y 1822, el botánico francés Auguste de Saint-Hilaire recorrió vastas extensiones del territorio brasileño, estudiando detenidamente la flora tropical pero sin dejar de interesarse en todo momento por la situación social y cultural de las poblaciones locales. Acumuló así un sinfín de observaciones, que desarrolló luego en pormenorizados relatos de viaje. En el último y más largo de sus periplos, llegó a la provincia de Rio Grande do Sul, y luego al territorio de la “Banda Oriental” (el Uruguay actual), dos regiones de clima más templado en donde censuró la predominancia de la economía ganadera y el consumo permanente de carne, y analizó los efectos psicológicos de una excesiva familiaridad con el espectáculo de la muerte de los vacunos. Ante ciertas escenas particularmente coloridas, los comentarios consignados en su diario de viaje ponen en evidencia una marcada brecha cultural, pero permiten también vislumbrar, detrás de la censura, del rechazo, y hasta del horror, una fascinación encubierta que, de alguna manera, res-ponde a la antigua y compleja relación simbólica del hombre con la carne animal

Streaming potential measurements 2. Relationship between electrical and hydraulic flow patterns from rock samples during deformation

Streaming potential and resistivity measurements have been performed on Fontainebleau sandstone and Villejust quartzite samples in a triaxial device during compaction, uniaxial compression, and rupture. Measurements on individual samples do not show any clear intrinsic dependence of the streaming potential coefficient with permeability. An apparent dependence of the streaming potential coefficient with permeability is, however, observed during deformation. The effect of surface conductivity is taken into account and is small compared with the observed changes in the streaming potential coefficient. The observed dependence is therefore interpreted in terms of a difference in the evolution of the electrical and hydraulic connectivity patterns during deformation. This effect causes the streaming potential coefficient, and consequently the inferred ξ potential, to be reduced by a geometrical factor R_G representing the electrical efficiency of the hydraulic network. Estimates of the R_G factor varying between 0.2 and 0.8 for electrolyte resistivity larger than 100 Ωm are obtained by comparing the values of the ξ potential inferred from intact rock samples with the values obtained from crushed rock samples, where the geometrical effects are assumed to be negligible. The reduction of the streaming potential coefficient observed during compaction or uniaxial compression suggests that the tortuosity of the hydraulic network increases faster than the tortuosity of the electrical network. Before rupture, an increase in the streaming potential coefficient associated with the onset of dilatancy was observed for three samples of Fontainebleau sandstone and one sample of Villejust quartzite. The changes in streaming potential coefficient prior to failure range from 30% to 50%. During one experiment, an increase in the concentration of sulfate ions was also observed before failure. These experiments suggest that observable streaming potential and geochemical variations could occur before earthquakes

Effective stress law for the permeability of a limestone

The effective stress law for the permeability of a limestone is studied experimentally by performing constant head permeability tests in a triaxial cell with different conditions of confining pressure and pore pressure. Test results have shown that a pore pressure increase and a confining pressure decrease both result in an increase of the permeability, and that the effect of the pore pressure change on the variation of the permeability is more important than the effect of a change of the confining pressure. A power law is proposed for the variation of the permeability with the effective stress. The permeability effective stress coefficient increases linearly with the differential pressure and is greater than one as soon the differential pressure exceeds few bars. The test results are well reproduced using the proposed permeability-effective stress law. A conceptual pore-shell model based on a detailed observation of the microstructure of the studied limestone is proposed. This model is able to explain the experimental observations on the effect of the total stress and of the pore pressure on the permeability of the limestone. Effective stress coefficients for the stress-dependent permeability which are greater than one are obtained. It is shown that the controlling factor is the ratio of the different bulk moduli of the various constituents of the rock. This ratio is studied experimentally by performing microhardness tests.Comment: International Journal of Rock Mechanics and Mining Sciences (2008) In pres