Du tajine à la poutine : Le cas de l’alimentation de jeunes Maghrébins nés au Québec et de leurs parents

Cet article porte sur les pratiques et représentations alimentaires ainsi que sur leurs processus de transformation, chez des populations migrantes issues du Maghreb et vivant à Montréal. Il relate les résultats d’entrevues de groupes réalisées auprès d’élèves de troisième cycle du primaire et de premier cycle du secondaire et auprès de leurs parents. Cette étude s’inscrit dans la continuité des recherches de Pierre Sercia (2007, 2004) portant sur l’intégration sociale des élèves fréquentant les écoles ethnoreligieuses. Les processus de transformations des pratiques alimentaires sont présentés comme des phénomènes de créolisation dans un espace social alimentaire multiculturel caractérisé par des logiques d’intégration, de fusion et de différenciation.This paper explores eating habits and representations along with the process of their transformation among migrant populations from the Maghreb living in Montreal. We interviewed children from the third level of primary school and teenagers from the first level of secondary school along with a few of their parents. This study continues the line of research developed by Pierre Sercia (2007, 2004), which focused on the social integration of immigrant students. The transformation process is defined as one of creolization in a multicultural alimentary social space and is characterized by the presence of integration, fusion and differentiation processes

Displacement Damage Effects in Pinned Photodiode CMOS Image Sensors

This paper investigates the effects of displacement damage in Pinned Photodiode (PPD) CMOS Image Sensors (CIS) using proton and neutron irradiations. The DDD ranges from 12 TeV/g to ${1.2 times 10^{6}}$ TeV/g. Particle fluence up to $5 times 10^{14}$ n.cm $^{-2}$ is investigated to observe electro-optic degradation in harsh environments. The dark current is also investigated and it would appear that it is possible to use the dark current spectroscopy in PPD CIS. The dark current random telegraph signal is also observed and characterized using the maximum transition amplitude

Five Conferences on Undecidability

These five lectures on undecidability were given to students with a good level in mathematics but with no special knowledge on logic. The first conference presents the formalization of mathematics with a short historical survey, the language of first order predicates and the axioms of set theory. The second and third lectures explain the incompleteness phenomena from the Hilbert program until Gödel's theorems with a presentation of the sequent calculus of Gentzen.The fourth talk deepens model theory reasoning in the case of the continuum hypothesis, and the last conference gives examples of effective computability results

Similarities Between Proton and Neutron Induced Dark Current Distribution in CMOS Image Sensors

Several CMOS image sensors were exposed to neutron or proton beams (displacement damage dose range from 4 TeV/g to 1825 TeV/g) and their radiation-induced dark current distributions are compared. It appears that for a given displacement damage dose, the hot pixel tail distributions are very similar, if normalized properly. This behavior is observed on all the tested CIS designs (4 designs, 2 technologies) and all the tested particles (protons from 50 MeV to 500 MeV and neutrons from 14 MeV to 22 MeV). Thanks to this result, all the dark current distribution presented in this paper can be fitted by a simple model with a unique set of two factors (not varying from one experimental condition to another). The proposed normalization method of the dark current histogram can be used to compare any dark current distribution to the distributions observed in this work. This paper suggests that this model could be applied to other devices and/or irradiation conditions

Barrier height distribution and dipolar relaxation in metal-insulator-semiconductor junctions with molecular insulator: Ageing effects

International audienceElectrical transport through molecular monolayers being very sensitive to disorder effects, admittance and current density characteristics of Hg // C12H25 – n Si junctions incorporating covalently bonded n-alkyl molecular layers, were investigated at low temperature (150-300 K), in the as-grafted state and after ageing at the ambient. This comparison reveals local oxidation effects both at the submicron scale in the effective barrier height distribution and at the molecular scale in the dipolar relaxation. In the bias range dominated by thermionic emission and modified by the tunnel barrier attenuation, , where is the thickness of the molecular tunnel barrier and is the inverse attenuation length at zero applied bias, some excess current is attributed to a distribution of low barrier height patches. Complementary methods are used to analyze the current density J(V, T) characteristics of Metal-Insulator-Semiconductor tunnel diodes. Assuming a Gaussian distribution of barrier heights centered at provides an analytical expression of the effective barrier height, ; this allows fitting of the distribution standard deviation and tunnel parameter over a wide temperature range. In a more realistic modeling including the voltage dependence of barrier height and circular patch area, the so-called “pinch-off” effect is described by a distribution of parameter which combines interface potential modulation and patch area variations. An arbitrary distribution of values, fitted to low-temperature J(V) data, is equally well described by Gaussian or exponential functions. Ageing in air also increases the interface oxidation of Si substrate and affects the density of localized states near mid gap, which typically rises to the high 1011 eV-1.cm-2 range, as compared with < 1011 eV-1.cm-2 in the as-grafted state. The bias-independent relaxation observed near 1 kHz at low temperature may be attributed either to dipoles in the alkyl chain induced by the strong permanent dipoles of interface silicon oxide or to a local relaxation of water molecules trapped at the OML / silicon interface. The respective roles of SiO2 formation and water physisorption on the decrease of patch barrier height are also discussed

Effect of high current density on the admittance response of interface states in ultrathin MIS tunnel junctions.

International audienceThe effect of a high current density on the measured admittance of ultrathin Metal-Insulator-Semiconductor (MIS) tunnel junctions is investigated to obtain a reliable energy distribution of the density, D-S(E), of defects localized at the semiconductor interface. The behavior of admittance Y(V, T, omega) and current density J(V, T) characteristics is illustrated by rectifying Hg//C12H25-Si junctions incorporating n-alkyl molecular layers (1.45 nm thick) covalently bonded to n-type Si(111). Modeling the forward bias admittance of a nonequilibrium tunnel junction reveals several regimes which can be observed either in C(omega approximate to 0) vs. (J) plots of the low frequency capacitance over six decades in current or in M ''(omega) plots of the electrical modulus over eight decades in frequency. At low current density, the response of interface states above mid-gap is unaffected and a good agreement is found between the interface states densities derived from the modeling of device response time tau(R)(V) and from the low-high frequency capacitance method valid for thick MIS devices; the low defect density near mid-gap (D-S 1 mA cm(-2)), the admittance depends strongly on both the density of localized states and the dc current density, so that the excess capacitance method overestimates D-S. For very high current densities > 10 mA cm(-2)), the observation of a linear C(omega approximate to 0) vs. (J) dependence could indicate some Fermi level pinning in a high interface density of states located near the Si conduction band. The temperature-independent excess capacitance C(omega approximate to 0) - C(1 MHz) observed at very small J, not predicted by the admittance model, is attributed to some dipolar relaxation in the molecular junction