Co-movements of international equity markets: a large-scale factor model approach

We analyze the comovements of a set of country-sector indexes from 45 different countries studying their factor decomposition based on a PCA analysis for a large cross section framework. We derive a measure to analyze the comovements over time based on the part of variance explained by the main extracted factors and we apply the method from Bai and Ng to study the relevant number of factors. We conduct rolling estimations for the period 1994-2006 focusing on the set of emerging markets. We show that both, emerging and developed equity markets experienced increasing comovements over the period of study, reflecting the integration of those markets. We have estimated that the main factor accounts for 30\% and 20\% of the whole variation of each data set. We use the comovements to gauge integration in two different ways, both indicating higher integration for developed markets. Finally, we relate the comovements to a measure of diversification and we conclude that it is only possible to reduce 85\% of the average risk of an equity index by diversification at the end of the period compared to 95\% at the beginning for the set of emerging markets.Market Integration, Equity markets, International portfolio diversification, Emerging Markets, Principal Components Analysis, Factor Analysis

The Relationship Between the Immigration Department and Community Organizations in the Integration of Immigrants in Quebec

This thesis is about the contemporary relationship between the Ministère de l’Immigration, de la Francisation et de l’Intégration (MIFI) and community organizations (COs) delivering immigrant integration services in Quebec. More precisely, it investigates the role of COs as central actors in the governance processes associated with immigrant integration policies in Quebec. The literature on the relationship between the Quebec government and COs points to the distinct recognition that autonomous community action (ACA) enjoys in the province. Although similar to other jurisdictions in its use of New Public Management (NPM) principles, the Quebec model is praised for the central role dedicated to civil society actors in governance processes. Based on a theoretical framework that synthesizes ACA and NPM as two opposing modes of action, this thesis presents an analysis of 10 semi-structured interviews with the leaders of COs active in this sector. First, the results of this research show that COs understand themselves as service providers in their relationship with the MIFI. This is present across the diverse COs analyzed, hinting at a powerful trend that may apply to the whole sector. Second, findings document that the COs interviewed experience difficulties in pursuing their social mission. The limited mission funding and the rare mechanisms COs have developed to foster citizen participation contribute to this situation. These results open the door to a broader reflection on the specificities of the Quebec model and on the changes in the value given to citizen participation in the development of public policies in the province

Interaction entre rugosités d'interfaces et ondes acoustiques guidées

L'étude porte sur la modélisation analytique des champs acoustiques en guides d'ondes fluides limités par des parois qui présentent des irrégularités de faibles dimensions en regard des dimensions transversales des guides et des longueurs d'ondes considérées. Les conditions aux frontières sont traduites par des conditions de Neumann sur le profil de rugosité, et la solution est recherchée par projection sur les modes propres d'un guide à géométrie compatible extérieur au guide réel, en faisant usage de la formulation intégrale avec une fonction de Green appropriée. La perturbation apportée par la rugosité est calculée par approximations successives, mettant en évidence deux mécanismes d'échanges d'énergie entre modes : l'un par couplage de volume et l'autre par couplage de surface, le premier dépendant de la profondeur de rugosité, et le deuxième dépendant de surcroît de la pente locale

Propagation guidée d'ondes de cisaillement horizontales dans des plaques solides rugueuses

La propagation des ondes de cisaillement à polarisation horizontale (ondes SH) dans des guides d'ondes isotropes à surfaces rugueuses fait apparaître des mécanismes de couplage de modes guidés. La modélisation de ces mécanismes est basée sur la formulation intégrale, et les solutions reposent sur des développements modaux en guide à géométrie compatible, extérieur au guide réel. Les résultats obtenus pour des rugosités périodiques sont en accord avec des résultats numériques de la littérature

Caractérisation statistique de la résistance en compression uniaxiale, de la résistance en tension et de l’indice de double poinçonnement du roc intact pour un projet minier

The design of excavation in underground mines relies on rock mass characterization. Intact rock properties are assessed according to the guidelines suggested by the International Society for Rock Mechanics. For laboratory testing, a minimum number of specimens must be analysed. This number is specific for a given test type. Nonetheless, rock variability, heterogeneity and anisotropy may suggest that a larger number of specimens could be necessary to fully assess rock mass properties. Furthermore, a characterization campaign must also respect certain practical and financial limitations. Using a case study from a Quebec mine site, this paper presents a methodology that allows directly linking the results of statistical analysis on campaign results to target levels of confidence for geotechnical data at all stages of a mining project

Mesoporous silica films with varying porous volume fraction: direct correlation between ortho-positronium annihilation decay and escape yield into vacuum

accepted for publication in Applied Physics LettersThe behavior of ortho-positronium (o-Ps) in mesoporous silica films implanted with low–energy positrons has been studied as a function of the film porous volume fraction. A lifetime spectrometer allowed determination of o-Ps annihilation decay both inside and outside of the film. A kinetic model is introduced that permits the determination of the yield and rate of escape of o-Ps into vacuum as well as the annihilation decay rate of the trapped o-Ps in the film. It is shown that these undergo a sudden change at a threshold porous volume fraction, above which the o-Ps escape rate to vacuum varies linearly with volume fraction

The origin of the legumes is a complex paleopolyploid phylogenomic tangle closely associated with the cretaceous-paleogene (K-Pg) mass extinction event

This is the final version. Available from Oxford University Press via the DOI in this record. The consequences of the Cretaceous-Paleogene (K-Pg) boundary (KPB) mass extinction for the evolution of plant diversity remain poorly understood, even though evolutionary turnover of plant lineages at the KPB is central to understanding assembly of the Cenozoic biota. The apparent concentration of whole genome duplication (WGD) events around the KPB may have played a role in survival and subsequent diversification of plant lineages. To gain new insights into the origins of Cenozoic biodiversity, we examine the origin and early evolution of the globally diverse legume family (Leguminosae or Fabaceae). Legumes are ecologically (co-)dominant across many vegetation types, and the fossil record suggests that they rose to such prominence after the KPB in parallel with several well-studied animal clades including Placentalia and Neoaves. Furthermore, multiple WGD events are hypothesized to have occurred early in legume evolution. Using a recently inferred phylogenomic framework, we investigate the placement of WGDs during early legume evolution using gene tree reconciliation methods, gene count data and phylogenetic supernetwork reconstruction. Using 20 fossil calibrations we estimate a revised timeline of legume evolution based on 36 nuclear genes selected as informative and evolving in an approximately clock-like fashion. To establish the timing of WGDs we also date duplication nodes in gene trees. Results suggest either a pan-legume WGD event on the stem lineage of the family, or an allopolyploid event involving (some of) the earliest lineages within the crown group, with additional nested WGDs subtending subfamilies Papilionoideae and Detarioideae. Gene tree reconciliation methods that do not account for allopolyploidy may be misleading in inferring an earlier WGD event at the time of divergence of the two parental lineages of the polyploid, suggesting that the allopolyploid scenario is more likely. We show that the crown age of the legumes dates to the Maastrichtian or early Paleocene and that, apart from the Detarioideae WGD, paleopolyploidy occurred close to the KPB. We conclude that the early evolution of the legumes followed a complex history, in which multiple auto- and/or allopolyploidy events coincided with rapid diversification and in association with the mass extinction event at the KPB, ultimately underpinning the evolutionary success of the Leguminosae in the Cenozoic.Swiss National Science FoundationUniversity of ZurichNatural Sciences and Engineering Research Council of CanadaNational Environment Research CouncilFonds de la Recherche Scientifique of Belgiu

Tissue-Specific Biomarker Responses in the Blue Mussel Mytilus spp. Exposed to a Mixture of Microplastics at Environmentally Relevant Concentrations

The impact of a microplastic (MP) mixture composed of polyethylene (PE) and polypropylene (PP) plastic particles, prepared from commercially available products, was evaluated in blue mussels Mytilus spp. exposed to three environmentally relevant concentrations: 0.008 μg L−1 (low), 10 μg L−1 (medium), and 100 μg L−1 (high). Organisms were exposed for 10 days followed by 10 days of depuration in clean seawater under controlled laboratory conditions. The evaluation of MP effects on mussel clearance rate, tissue structure, antioxidant defenses, immune and digestive parameters, and DNA integrity were investigated while the identification of plastic particles in mussel tissues (gills, digestive gland, and remaining tissues), and biodeposits (feces and pseudofaeces) was performed using infrared microscopy (μFT-IR). Results showed the presence of MPs only in the digestive gland of mussels exposed to the highest tested concentration of MPs with a mean of 0.75 particle/mussel (after the 10 days of exposure). In biodeposits, PE and PP particles were detected following exposure to all tested concentrations confirming the ingestion of MPs by the organisms. A differential response of antioxidant enzyme activities between digestive gland and gills was observed. Significant increases in superoxide dismutase (SOD) and catalase (CAT) activities were measured in the digestive gland of mussels exposed to the low (0.008 μg L−1) and medium (10 μg L−1) concentrations of MPs and in the gills from mussels exposed to the highest concentration (100 μg L−1) of MPs that could be indicative of a change in the redox balance. Moreover, an increase in acid phosphatase activity was measured in hemolymph of mussels exposed to 0.008 and 10 μg L−1 concentrations. No significant difference was observed in the clearance rate, and histopathological parameters between control and exposed mussels. This study brings new insights on the potential sublethal impacts of MPs at environmentally relevant concentrations in marine bivalves

Large-scale genomic sequence data resolve the deepest divergences in the legume phylogeny and support a near-simultaneous evolutionary origin of all six subfamilies

info:eu-repo/semantics/publishe