La nouvelle immigration chinoise au Canada et au Québec dans le cadre de la mondialisation

Basée sur l’analyse des données officielles, cette recherche propose une étude sur le lien entre les nouveaux flux migratoires internationaux des Chinois, qui se produisent à partir des années 2000, et l’évolution des profils et des performances économiques des immigrants chinois au Canada et au Québec. Le but de ce mémoire est d’observer la quantité et la qualité de ces nouveaux arrivants vis-à-vis leurs performances après l’immigration. Les nouveaux immigrants en provenance de la Chine continentale sont différents des précédents dans la mesure où les riches et les élites sont devenus majoritaires. Ces nouveaux flux sont aussi accompagnés d’une forte croissance du nombre d’étudiants chinois qui font leurs études à l’international et du nombre d’immigrants de retour. Néanmoins, les résultats ne démontrent pas que leurs performances au Canada et au Québec s’améliorent même s’ils ont des profils plus qualifiés et plus jeunes. Évidemment, l’arrivée de ces immigrants chinois récents a des conséquences importantes. À cause des forts changements de la condition économique et sociale interne en Chine, ces flux de personnes ne cesseront pas de croître dans le futur proche. Ainsi, les décideurs du Canada et du Québec doivent porter plus d’attention et réagir au mieux face à cette tendance.

La pratique de la contrepartie pour les personnes exclues du marché du travail : ici et ailleurs

Les modalités et les pratiques de la contrepartie dans l’assistance sociale, dans six pays de l’OCDE sont comparés. La littérature anglo-saxonne parle plus volontiers de workfare alors que la littérature d’Europe continentale utilise la notion de conditionnalité. Les auteurs utilisent le terme de contrepartie comme concept générique incluant l’ensemble des programmes introduisant des formes de conditionnalité de l’aide par opposition à des aides ou des prestations attribuées de manière inconditionnelle. Une interprétation de ces variations est proposée en situant les résultats obtenus par rapport aux connaissances acquises en politique comparée sur l’évolution des différents types d’État-providence.

Les frontières culturelles et politiques du monde mycénien

Le bassin oriental de la Méditerranée à l’âge du bronze égéen est un ensemble hétérogène où s’entremêlent plusieurs cultures : Égyptiens, Hittites, Minoens et Mycéniens se côtoient et interagissent à divers degrés. Un examen méticuleux des sources archéologiques et épigraphiques permet de mettre un peu d’ordre à cette mosaïque chaotique afin de mieux apprécier les interactions entre ces cultures. La culture mycénienne est celle à laquelle s’intéresse particulièrement cette présente étude. Bien que son coeur soit unanimement localisé en Grèce continentale, la culture mycénienne se répand également de l’Italie jusqu’au Levant et de la Thrace à l’Égypte. Selon l’importance et la nature des vestiges, l’archéologie ordonne en trois catégories les régions où se retrouve la culture mycénienne, alors que les sources épigraphiques hittites et égyptiennes permettent de remettre en question la société mycénienne et de localiser les frontières politiques de cette culture.

Martin Heidegger and the problem of transcendence

Cette thèse a pour point de départ l’idée du jeune Heidegger selon laquelle le sens de l’être doit être recherché au moyen d’une phénoménologie ontologique, plus précisément par l’analytique existentiale du Dasein et la destruction de l’histoire de l’ontologie ; ou, comme nous l’interprétons, dans la transcendance du Dasein et la transcendance de l’être. L’étude du problème de la transcendance fait l’objet d’une approche phénoménologique, laquelle porte une attention particulière au vécu en tant que tel ainsi qu’aux conditions de possibilité de ce vécu, et repose sur une lecture attentive et critique des œuvres de Heidegger. C’est une telle approche phénoménologique qui nous permettra de mener à bien notre analyse du problème de la transcendance dans le corpus heideggérien. Nous serons par ailleurs en mesure d’aborder le débat opposant à ce sujet la tradition analytique (plus particulièrement l’approche pragmatiste) et la tradition continentale, notre étude s’inscrivant dans le cadre de cette dernière. Nous proposons ici une phénoménologie du problème de la transcendance qui fait également figure de phénoménologie du sens, de la possibilité et de la normativité. Prenant pour point de départ certaines contributions issues de la tradition continentale, nous soutenons que le sens de l’être peut être compris comme le problème de la transcendance. L’histoire de la philosophie doit être perturbée, déconstruite et repensée afin que le chemin de la philosophie, encore non pensé, puisse être mis au jour. L’accès à cet autre commencement doit être recherché dans la transcendance en tant que telle – de l’appel de la conscience fondé dans la nullité à l’encontre authentique avec la mort et l’ouverture de la temporalité ; de l’avènement historial de l’être jusqu’à, ultimement, le i! ! ! ! refus de l’être et le retrait du rien. L’événement (Ereignis) de l’être est donc compris comme processus de dépassement de soi à partir duquel la transcendance de l’être – ou, comme le formule Heidegger, la fin des questions – est possible.

Investigations on the Effects of Petroleum Hydrocarbons on the Marine Bivalves Perna viridis (Linnaeus) and Sunetta scripta (Linne')

The thesis deals with different aspects connected with the distribution and toxicity of PHC in crude oils in the aquatic environment and marine molluscs. Information has been gathered and presented on the present status of research in the field based on a thorough review of recent literature. It is seen from the literature that the resident time of PHC becomes lesser and lesser when crude oil is discharged in large quantities into the coastal waters where excess oxygenation light penetration, temperature availability and strong tidal currents persist. This results in the reduction of the onslaught of oil pollution. This probably shows that taxic insult of crude oil in tropical shores will be relatively lesser than that occurring in temperate and boreal waters. However, there is no record of major episodal oil pollution comparable in quantum and extent to that of Torrey Canyon or Amoco Cadiz which prevents a more reliable analysis on the issue. Considerable controversy exists on the method of estimation of PHC in seawater. However, Ultra-violet fluorescence spectroscopy has been widely recommended as an analytical tool for the determination of total hydrocarbons. Similarly representation of values as chrysene equivalents has been recognised as the most reliable method of Quantum representation.

Reflexiones en torno al concepto de vida

Esto texto examina cuatro conceptos de vida que se consideran notables en el siglo XX, los contrasta y propone algunos aspectos que pueden enriquecer el concepto.

Prospectiva y vigilancia tecnológica en la cadena fibra-textil-confecciones. Mapa tecnológico estratégico, nuevos escenarios para el futuro de la cadena productiva fibra textil confección de Colombia

Este libro es el resultado de una investigación exhaustiva sobre el impacto que el cambio tecnológico tiene sobre la cadena productiva de fibra-textil-confección. Los autores logran demostrar cómo esta cadena pasó de ser utilizadora de tecnología a generadora de nuevas tecnologías, asociadas a la nueva economía digital, como lo son la biotecnología, la microelectrónica, las tecnologías de la información y la comunicación y la nano tecnología. Por lo tanto, dada la importancia del sector textil confección para Colombia, los autores llaman la atención sobre las consecuencias de esta situación. En este sentido, identifican las llamadas brechas de competitividad y tecnología que separan a las empresas colombianas frente al estado del arte de quienes lideran el sector a nivel mundial. Para cerrar las brechas, los autores proponen una cartera de proyectos que son presentados en su contexto sistémico, es decir, que buscan generar impactos en toda la cadena de valor, y no solamente hacia un solo eslabón de la misma.

Representaciones sociales de la medicina complementaria y alternativa (MCA) para el cáncer en estudiantes universitarios de carreras de ciencias de la salud

Se realizó un estudio cualitativo exploratorio con estudiantes de carreras de Ciencias de la Salud con el objetivo de comprender las representaciones sociales que tienen acerca de la Medicina Complementaria y Alternativa (MCA) para el cáncer. Se desarrollaron grupos focales y la información obtenida fue analizada a través del Análisis Temático e interpretada con base en la Teoría de las Representaciones Sociales. Se encontraron diversas representaciones sociales asociadas con la definición, los objetivos, los tratamientos, la eficacia, las fuentes de información y el origen de la MCA. En conclusión se evidenció una alta tendencia a la aceptación y a la manifestación de una actitud positiva, aunque ambivalente frente a la MCA, además de un desconocimiento por la diferenciación conceptual entre este tipo de Medicina y la Medicina Popular. La cultura y las creencias sociales predominan en las representaciones sociales que tienen los estudiantes de la MCA para el cáncer, pese a su formación académica.

Spatial variability of flow statistics within regular building arrays

Turbulence statistics obtained by direct numerical simulations are analysed to investigate spatial heterogeneity within regular arrays of building-like cubical obstacles. Two different array layouts are studied, staggered and square, both at a packing density of λp=0.25 . The flow statistics analysed are mean streamwise velocity ( u− ), shear stress ( u′w′−−−− ), turbulent kinetic energy (k) and dispersive stress fraction ( u˜w˜ ). The spatial flow patterns and spatial distribution of these statistics in the two arrays are found to be very different. Local regions of high spatial variability are identified. The overall spatial variances of the statistics are shown to be generally very significant in comparison with their spatial averages within the arrays. Above the arrays the spatial variances as well as dispersive stresses decay rapidly to zero. The heterogeneity is explored further by separately considering six different flow regimes identified within the arrays, described here as: channelling region, constricted region, intersection region, building wake region, canyon region and front-recirculation region. It is found that the flow in the first three regions is relatively homogeneous, but that spatial variances in the latter three regions are large, especially in the building wake and canyon regions. The implication is that, in general, the flow immediately behind (and, to a lesser extent, in front of) a building is much more heterogeneous than elsewhere, even in the relatively dense arrays considered here. Most of the dispersive stress is concentrated in these regions. Considering the experimental difficulties of obtaining enough point measurements to form a representative spatial average, the error incurred by degrading the sampling resolution is investigated. It is found that a good estimate for both area and line averages can be obtained using a relatively small number of strategically located sampling points.

How many facets are needed to represent the surface energy balance of an urban area?

We investigate the question of how many facets are needed to represent the energy balance of an urban area by developing simplified 3-, 2- and 1-facet versions of a 4-facet energy balance model of two-dimensional streets and buildings. The 3-facet model simplifies the 4-facet model by averaging over the canyon orientation, which results in similar net shortwave and longwave balances for both wall facets, but maintains the asymmetry in the heat fluxes within the street canyon. For the 2-facet model, on the assumption that the wall and road temperatures are equal, the road and wall facets can be combined mathematically into a single street-canyon facet with effective values of the heat transfer coefficient, albedo, emissivity and thermodynamic properties, without further approximation. The 1-facet model requires the additional assumption that the roof temperature is also equal to the road and wall temperatures. Idealised simulations show that the geometry and material properties of the walls and road lead to a large heat capacity of the combined street canyon, whereas the roof behaves like a flat surface with low heat capacity. This means that the magnitude of the diurnal temperature variation of the street-canyon facets are broadly similar and much smaller than the diurnal temperature variation of the roof facets. Consequently, the approximation that the street-canyon facets have similar temperatures is sound, and the road and walls can be combined into a single facet. The roof behaves very differently and a separate roof facet is required. Consequently, the 2-facet model performs similarly to the 4-facet model, while the 1-facet model does not. The models are compared with previously published observations collected in Mexico City. Although the 3- and 2-facet models perform better than the 1-facet model, the present models are unable to represent the phase of the sensible heat flux. This result is consistent with previous model comparisons, and we argue that this feature of the data cannot be produced by a single column model. We conclude that a 2-facet model is necessary, and for numerical weather prediction sufficient, to model an urban surface, and that this conclusion is robust and therefore applicable to more general geometries.

Referencing of street-level flows measured during the DAPPLE 2004 campaign

Street-level mean flow and turbulence govern the dispersion of gases away from their sources in urban areas. A suitable reference measurement in the driving flow above the urban canopy is needed to both understand and model complex street-level flow for pollutant dispersion or emergency response purposes. In vegetation canopies, a reference at mean canopy height is often used, but it is unclear whether this is suitable for urban canopies. This paper presents an evaluation of the quality of reference measurements at both roof-top (height = H) and at height z = 9H = 190 m, and their ability to explain mean and turbulent variations of street-level flow. Fast response wind data were measured at street canyon and reference sites during the six-week long DAPPLE project field campaign in spring 2004, in central London, UK, and an averaging time of 10 min was used to distinguish recirculation-type mean flow patterns from turbulence. Flow distortion at each reference site was assessed by considering turbulence intensity and streamline deflection. Then each reference was used as the dependent variable in the model of Dobre et al. (2005) which decomposes street-level flow into channelling and recirculating components. The high reference explained more of the variability of the mean flow. Coupling of turbulent kinetic energy was also stronger between street-level and the high reference flow rather than the roof-top. This coupling was weaker when overnight flow was stratified, and turbulence was suppressed at the high reference site. However, such events were rare (<1% of data) over the six-week long period. The potential usefulness of a centralised, high reference site in London was thus demonstrated with application to emergency response and air quality modelling.

A field study of factors influencing the concentrations of a traffic-related pollutant in the vicinity of a complex urban junction

The paper describes a field study focused on the dispersion of a traffic-related pollutant within an area close to a busy intersection between two street canyons in Central London. Simultaneous measurements of airflow, traffic flow and carbon monoxide concentrations ([CO]) are used to explore the causes of spatial variability in [CO] over a full range of background wind directions. Depending on the roof-top wind direction, evidence of both flow channelling and recirculation regimes were identified from data collected within the main canyon and the intersection. However, at the intersection, the merging of channelled flows from the canyons increased the flow complexity and turbulence intensity. These features, coupled with the close proximity of nearby queuing traffic in several directions, led to the highest overall time-average measured [CO] occurring at the intersection. Within the main street canyon, the data supported the presence of a helical flow regime for oblique roof-top flows, leading to increased [CO] on the canyon leeward side. Predominant wind directions led to some locations having significantly higher diurnal average [CO] due to being mostly on the canyon leeward side during the study period. For all locations, small changes in the background wind direction could cause large changes in the in-street mean wind angle and local turbulence intensity, implying that dispersion mechanisms would be highly sensitive to small changes in above roof flows. During peak traffic flow periods, concentrations within parallel side streets were approximately four times lower than within the main canyon and intersection which has implications for controlling personal exposure. Overall, the results illustrate that pollutant concentrations can be highly spatially variable over even short distances within complex urban geometries, and that synoptic wind patterns, traffic queue location and building topologies all play a role in determining where pollutant hot spots occur.

An eclectic morphostratigraphic model for the sedimentary response to Holocene sea-level rise in northwest Europe

The improved empirical understanding of silt facies in Holocene coastal sequences provided by such as diatom, foraminifera, ostracode and testate amoebae analysis, combined with insights from quantitative stratigraphic and hydraulic simulations, has led to an inclusive, integrated model for the palaeogeomorphology, stratigraphy, lithofacies and biofacies of northwest European Holocene coastal lowlands in relation to sea-level behaviour. The model covers two general circumstances and is empirically supported by a range of field studies in the Holocene deposits of a number of British estuaries, particularly, the Severn. Where deposition was continuous over periods of centuries to millennia, and sea level fluctuated about a rising trend, the succession consists of repeated cycles of silt and peat lithofacies and biofacies in which series of transgressive overlaps (submergence sequences) alternate with series of regressive overlaps (emergence sequences) in association with the waxing and waning of tidal creek networks. Environmental and sea-level change are closely coupled, and equilibrium and secular pattern is of the kind represented ideally by a closed limit cycle. In the second circumstance, characteristic of unstable wetland shores and generally affecting smaller areas, coastal erosion ensures that episodes of deposition in the high intertidal zone last no more than a few centuries. The typical response is a series of regressive overlaps (emergence sequence) in erosively based high mudflat and salt-marsh silts that record, commonly as annual banding, exceptionally high deposition rates and a state of strong disequilibrium. Environmental change, including creek development, and sea-level movement are uncoupled. Only if deposition proceeds for a sufficiently long period, so that marshes mature, are equilibrium and close coupling regained. (C) 2002 Elsevier Science B.V. All rights reserved.

In-street wind direction variability in the vicinity of a busy intersection in central London

We present results from fast-response wind measurements within and above a busy intersection between two street canyons (Marylebone Road and Gloucester Place) in Westminster, London taken as part of the DAPPLE (Dispersion of Air Pollution and Penetration into the Local Environment; www.dapple.org.uk) 2007 field campaign. The data reported here were collected using ultrasonic anemometers on the roof-top of a building adjacent to the intersection and at two heights on a pair of lamp-posts on opposite sides of the intersection. Site characteristics, data analysis and the variation of intersection flow with the above-roof wind direction (θref) are discussed. Evidence of both flow channelling and recirculation was identified within the canyon, only a few metres from the intersection for along-street and across-street roof-top winds respectively. Results also indicate that for oblique rooftop flows, the intersection flow is a complex combination of bifurcated channelled flows, recirculation and corner vortices. Asymmetries in local building geometry around the intersection and small changes in the background wind direction (changes in 15-min mean θref of 5–10 degrees) were also observed to have profound influences on the behaviour of intersection flow patterns. Consequently, short time-scale variability in the background flow direction can lead to highly scattered in-street mean flow angles masking the true multi-modal features of the flow and thus further complicating modelling challenges.