277 research outputs found
Du tajine Ă la poutine : Le cas de lâalimentation de jeunes MaghrĂ©bins nĂ©s au QuĂ©bec et de leurs parents
Cet article porte sur les pratiques et reprĂ©sentations alimentaires ainsi que sur leurs processus de transformation, chez des populations migrantes issues du Maghreb et vivant Ă MontrĂ©al. Il relate les rĂ©sultats dâentrevues de groupes rĂ©alisĂ©es auprĂšs dâĂ©lĂšves de troisiĂšme cycle du primaire et de premier cycle du secondaire et auprĂšs de leurs parents. Cette Ă©tude sâinscrit dans la continuitĂ© des recherches de Pierre Sercia (2007, 2004) portant sur lâintĂ©gration sociale des Ă©lĂšves frĂ©quentant les Ă©coles ethnoreligieuses. Les processus de transformations des pratiques alimentaires sont prĂ©sentĂ©s comme des phĂ©nomĂšnes de crĂ©olisation dans un espace social alimentaire multiculturel caractĂ©risĂ© par des logiques dâintĂ©gration, de fusion et de diffĂ©renciation.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 TeV/g. Particle fluence up to n.cm 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
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
GEOTHERMAL EXPLORATION IN MARTINIQUE BASED ON MAGNETO-TELLURIC AND CONTROLLED-SOURCE EM SURVEY
International audienceResistivity imaging is a key input in many geothermal exploration programs, and particularly in volcanic environment. It is assumed that resistivity variations allow imaging the caprock, but also hydrothermal weathering and preferential geothermal fluid flow. The latter is generally a brine which drastically decreases the electrical resistivity and the temperature increase also lowers resistivity. Several authors have described resistivity signatures for some geothermal reservoirs context. Magnetotelluric (MT) is generally used to image resistivity variations down to a relevant investigation depth of several kilometers. Within the framework of a global French program oriented towards the development of geothermal energy, Martinique Island (Lesser Antilles, France) has been extensively investigated (from 2012 to 2013) through an integrated multi-method approach, with the aim to define precisely the potential geothermal structures previously highlighted. Amongst the common investigation methods deployed, we carried out three magnetotelluric (MT) surveys located above three out of the most promising geothermal areas of Martinique, namely the Anses d'Arlet (focus of this presentation), the Montagne Pelée and the Pitons du Carbet prospects. Based on natural source signal, the quality of broad band MT data depends on the source activity (lightning strikes and sun) during the survey but also on the local noise conditions. In many cases, because industrial activities have been developed close to the geothermal resource, the noise conditions make it difficult to obtain reliable MT tensors and therefore a good resistivity distribution. A common way to improve the data quality is to record longer time series and to apply robust processing with remote reference including noise filtering
Influence of displacement damage dose on dark current distributions of irradiated CMOS image sensors
Dark current increase distributions due to displacement damages are modeled using displacement damage dose concept. Several CMOS image sensors have been exposed to neutrons or protons and we have characterized their degradation in terms of dark current increase. We have been able to extract a set of two factors from the experimental dark current increase distributions. These factors are used to predict and build dark current increase distribution and leads to a better understanding of displacement damage effects on CMOS image sensors
Spodoptera frugiperda transcriptional response to infestation by Steinernema carpocapsae
Steinernema carpocapsae is an entomopathogenic nematode (EPN) used in biological control of agricultural pest insects. It enters the hemocoel of its host via the intestinal tract and releases its symbiotic bacterium Xenorhabdus nematophila. In order to improve our knowledge about the physiological responses of its different hosts, we examined the transcriptional responses to EPN infestation of the fat body, the hemocytes and the midgut in the lepidopteran pest Spodoptera frugiperda. The tissues poorly respond to the infestation at an early time post-infestation of 8 h with only 5 genes differentially expressed in the fat body of the caterpillars. Strong transcriptional responses are observed at a later time point of 15 h post-infestation in all three tissues. Few genes are differentially expressed in the midgut but tissue-specific panels of induced metalloprotease inhibitors, immune receptors and antimicrobial peptides together with several uncharacterized genes are up-regulated in the fat body and the hemocytes. Among the most up-regulated genes, we identified new potential immune effectors, unique to Lepidoptera, which show homology with bacterial genes of unknown function. Altogether, these results pave the way for further functional studies of the responsive genes' involvement in the interaction with the EPN
Spodoptera frugiperda immune response to the nematobacterial complex Steinernema carpocapsae-Xenorhabdus nematophila
[i]Spodoptera frugiperda[/i] immune response to the nematobacterial complex [i]Steinernema carpocapsae-Xenorhabdus nematophila[/i]. Conférences Jacques Monod "Immunologie Intégrative des Insectes : ContrÎle des Infections
3-D Magnetotelluric Investigations for geothermal exploration in Martinique (Lesser Antilles). Characteristic Deep Resistivity Structures, and Shallow Resistivity Distribution Matching Heliborne TEM Results
Within the framework of a global French program oriented towards the
development of renewable energies, Martinique Island (Lesser Antilles, France)
has been extensively investigated (from 2012 to 2013) through an integrated
multi-methods approach, with the aim to define precisely the potential
geothermal ressources, previously highlighted (Sanjuan et al., 2003). Amongst
the common investigation methods deployed, we carried out three magnetotelluric
(MT) surveys located above three of the most promising geothermal fields of
Martinique, namely the Anses d'Arlet, the Montagne Pel{\'e}e and the Pitons du
Carbet prospects. A total of about 100 MT stations were acquired showing single
or multi-dimensional behaviors and static shift effects. After processing data
with remote reference, 3-D MT inversions of the four complex elements of MT
impedance tensor without pre-static-shift correction, have been performed for
each sector, providing three 3-D resistivity models down to about 12 to 30 km
depth. The sea coast effect has been taken into account in the 3-D inversion
through generation of a 3-D resistivity model including the bathymetry around
Martinique from the coast up to a distance of 200 km. The forward response of
the model is used to calculate coast effect coefficients that are applied to
the calculated MT response during the 3-D inversion process for comparison with
the observed data. 3-D resistivity models of each sector, which are inherited
from different geological history, show 3-D resistivity distribution and
specificities related to its volcanological history. In particular, the
geothermal field related to the Montagne Pel{\'e}e strato-volcano, is
characterized by a quasi ubiquitous conductive layer and quite monotonic
typical resistivity distribution making interpretation difficult in terms of
geothermal targets. At the opposite, the resistivity distribution of Anse
d'Arlet area is radically different and geothermal target is thought to be
connected to a not so deep resistive intrusion elongated along a main
structural axis. Beside these interesting deep structures, we demonstrate,
after analyzing the results of the recent heliborne TEM survey covering the
whole Martinique, that surface resistivity distribution obtained from 3-D
inversion reproduce faithfully the resistivity distribution observed by TEM. In
spite of a very different sampling scale, this comparison illustrates the
ability of 3-D MT inversion to take into account and reproduce static shift
effects in the sub-surface resistivity distribution.Comment: Wordl Geothermal Congress 2015, Apr 2015, Melbourne, Australi
La gestion des Activités éducatives de la direction et le fonctionnement de l'école primaire
Many actors in the field of education assert that principals should pay closer attention to educational activities in order to ensure students' achievement. This paper presents a research conducted with 138 principals and 421 teachers which aimed at assessing the frequency of principals' interventions on managing educational activities in elementary schools in Quebec. In addition, this study examines the relations between principals' management of educational activities and the different aspect of the school's functioning. The results show that principals intervene more frequently in specific areas of management such as parents' involvement and the support of at-risk students rather than the supervision of teachers and students' performance. Hence, the quality of the school's functioning varies in the nature and frequency of the principal's intervention which illustrates the importance of their managerial work.Key words: management of educational activities, educational leadership, school's functioning, students' achievement
Effect of nitrogen-rich cell culture surfaces on type X collagen expression by bovine growth plate chondrocytes
Background: Recent evidence indicates that osteoarthritis (OA) may be a systemic disease since mesenchymal stem cells (MSCs) from OA patients express type X collagen, a marker of late stage chondrocyte hypertrophy (associated with endochondral ossification). We recently showed that the expression of type X collagen was suppressed when MSCs from OA patients were cultured on nitrogen (N)-rich plasma polymer layers, which we call "PPE:N" (N-doped plasma-polymerized ethylene, containing up to 36 atomic percentage (at.%) of N.Methods: In the present study, we examined the expression of type X collagen in fetal bovine growth plate chondrocytes (containing hypertrophic chondrocytes) cultured on PPE:N. We also studied the effect of PPE: N on the expression of matrix molecules such as type II collagen and aggrecan, as well as on proteases (matrix metalloproteinase-13 (MMP-13) and molecules implicated in cell division (cyclin B2). Two other culture surfaces, "hydrophilic" polystyrene (PS, regular culture dishes) and nitrogen-containing cation polystyrene (Primaria (R)), were also investigated for comparison.Results: Results showed that type X collagen mRNA levels were suppressed when cultured for 4 days on PPE: N, suggesting that type X collagen is regulated similarly in hypertrophic chondrocytes and in human MSCs from OA patients. However, the levels of type X collagen mRNA almost returned to control value after 20 days in culture on these surfaces. Culture on the various surfaces had no significant effects on type II collagen, aggrecan, MMP-13, and cyclin B2 mRNA levels.Conclusion: Hypertrophy is diminished by culturing growth plate chondrocytes on nitrogen-rich surfaces, a mechanism that is beneficial for MSC chondrogenesis. Furthermore, one major advantage of such "intelligent surfaces" over recombinant growth factors for tissue engineering and cartilage repair is potentially large cost-saving
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