Modélisation dynamo des cycles d’activité stellaire

Des décennies d’observation ont permis d’obtenir différentes relations liées à l’activité stellaire. Cependant, il est difficile de reproduire numériquement celles-ci à partir de modèles dynamo, puisqu’il n’y a pas de consensus sur le processus réellement présent dans les étoiles. Nous tentons de reproduire certaines de ces relations avec un modèle global 3D hydrodynamique qui nous fournit le profil de rotation différentielle et le tenseur-α utilisés en entrée dans un modèle de dynamo αΩ. Nous reproduisons ainsi efficacement la corrélation positive entre le rapport P_cyc⁄P_rot et P_rot^(-1). Par contre, nous échouons à reproduire les relations liant ω_cyc⁄Ω et l’énergie magnétique au nombre de Rossby. Cela laisse croire que la variation de P_cyc⁄P_rot avec la période de rotation est une caractéristique robuste du modèle αΩ, mais que l’effet-α ne serait pas le processus principal limitant l’amplitude du cycle. Cette saturation découlerait plutôt de la réaction magnétique sur l’écoulement à grande échelle.Decades of stellar observations established various relationships related to stellar activity cycles. However, these are difficult to numerically reproduce using dynamo models, since flows important for dynamo action cannot be measured in stars other than the Sun. We model these relationships by extracting the differential rotation profile and the α-tensor from a global 3D hydrodynamical simulation and use them as an input into a αΩ dynamo model. We succeed in reproducing the observed positive correlation between the ratio P_cyc⁄P_rot and P_rot^(-1). On the other hand, we fail to do so for the relationship linking ω_cyc⁄Ω and the magnetic energy to the Rossby number. This indicates that the variation of P_cyc⁄P_rot with the rotation period is a robust feature of the αΩ model, but that the α-effect is probably not the main process limiting cycle amplitude. This saturation is most likely related to the magnetic backreaction on large-scale flows

De l'évolution du motif de discrimination illicite "handicap" compris à l'article 10 de la Charte québécoise aux différentes tendances et perspectives de la conception dualiste de cette expression

Résumé: En 1978, le législateur québécois introduisit dans l'article 10 de la Charte québécoise un nouveau motif de discrimination, celui de "personne handicapée". Le fait d'être une personne handicapée allait enfin permettre à ceux qui répondaient aux critères de l'article lg) de la Loi assurant l'exercice des droits des personnes handicapées d'être protégés contre ce type de discrimination. En 1983, le législateur amenda la Charte québécoise pour substituer la notion de "handicap" à celle de "personne handicapée". Toutefois, il ne précisa pas ce qu'il entendait par cette expression. Comment peut-on définir le "handicap"? Ce travail répond à cette question et à d'autres qui concernent cette terminologie et son évolution. L'auteure analyse d'abord les prémices des expressions "personne handicapée" et "handicap". Elle aborde ensuite une décision de la Cour supérieure afin d'exposer et de critiquer les différentes positions qui s'affrontent présentement au Tribunal des droits de la personne concernant l'expression "handicap". Elle propose, pour terminer, une définition de cette notion en démontrant que le concept de handicap repose essentiellement sur un traitement social des caractéristiques individuelles.||Abstract: ln 1978, the Quebec legislator introduced a new concept within article 10 of Quebec Charter: "handicapped person". The fact that you were a handicapped person would finally allow those meeting the criterias listed in article 1g) of the legislation guaranteeing rights to handicapped person, to be protected againts any types of discrimination. In 1983, the legislator amended the Quebec Charter to substitute the notion of "handicap" to "handicappped person". However, this expression was not defined. How can one define "handicap"? Who'can profit from the protection of this notion? This thesis answers these questions and others concerning this terminology and its evolution. The autor first analyses premisses related to the expressions "handicapped persons" and "handicap". Then she tackles a Superior court affair in order to expose and criticize different positions presently dealt with at the Persons Rights Tribunal and its also related to the expression "handicap". At the end, she proposes a definition of this notion in demonstrating that the concept of handicap is based essentially on the social perception of individual characteristics

Impacts des emprises de lignes électriques sur la végétation des tourbières

Les infrastructures linéaires sont reconnues pour faciliter la dispersion de plantes indésirables dans leur emprise et les habitats adjacents. Toutefois, les impacts des emprises de lignes électriques ont été peu étudiés, particulièrement en milieux humides. Cette étude a examiné la végétation des emprises de lignes électriques et de leurs habitats adjacents dans 23 tourbières ombrotrophes (bogs) et 11 minérotrophes (fens). Dans les fens, la dispersion des espèces indésirables est facilitée le long des emprises et certaines espèces peuvent se propager à plus de 43 m dans les habitats adjacents. Au contraire, ces infrastructures ne semblent pas favoriser la dispersion des espèces indésirables dans les bogs puisque leur présence était limitée à la marge des sites et était négligeable dans les habitats tourbeux adjacents. Finalement, les caractéristiques intrinsèques des tourbières, telles leur degré de minérotrophie (bog ou fen) et leur structure végétale (tourbière ouverte, semi-forestière ou forestière) semblent grandement influencer l’envahissement.Linear infrastructures are known to facilitate the spread of undesirable plants within their right-of-way (ROW) as well as in adjacent habitats. However, the impacts of power-lines ROWs have been weakly studied, particularly in wetlands. This study examined the vegetation of 23 ombrotrophic (bogs) and 11 minerotrophic (fens) peatlands intersected by a power-line ROW. The results showed that the spread of undesirable species along the feature is possible in fens and that some of those species could disperse into the adjacent habitat to more than 43 m from the ROW. Inversely, those features seemed to be inefficient dispersal vectors in bogs, because undesirable species were restricted to the bog margin in the ROW, and almost none dispersed in the adjacent habitats. Finally, intrinsic characteristics of peatlands, such as their degree of minerotrophy (bog or fen) and their vegetation type (open, semiforested or wooded peatland) seem to be important factors influencing invasion

Unusual duplication of the insulin-like receptor in the crustacean Daphnia pulex

Background: The insulin signaling pathway (ISP) has a key role in major physiological events like carbohydrate metabolism and growth regulation. The ISP has been well described in vertebrates and in a few invertebrate model organisms but remains largely unexplored in non-model invertebrates. This study is the first detailed genomic study of this pathway in a crustacean species, Daphnia pulex. Results: The Daphnia pulex draft genome sequence assembly was scanned for major components of the ISP with a special attention to the insulin-like receptor. Twenty three putative genes are reported. The pathway appears to be generally well conserved as genes found in other invertebrates are present. Major findings include a lower number of insulin-like peptides in Daphnia as compared to other invertebrates and the presence of multiple insulin-like receptors (InR), with four genes as opposed to a single one in other invertebrates. Genes encoding for the Dappu_InR are likely the result of three duplication events and bear some unusual features. Dappu_InR-4 has undergone extensive evolutionary divergence and lacks the conserved site of the catalytic domain of the receptor tyrosine kinase. Dappu_InR-1 has a large insert and lacks the transmembranal domain in the b-subunit. This domain is also absent in Dappu_InR-3. Dappu_InR-2 is characterized by the absence of the cystein-rich region. Real-time q-PCR confirmed the expression of all four receptors. EST analyses of cDNA libraries revealed that the four receptors were differently expressed under various conditions. Conclusions: Duplications of the insulin receptor genes might represent an important evolutionary innovation in Daphnia as they are known to exhibit extensive phenotypic plasticity in body size and in the size of defensive structures in response to predation

Epidemiological and evolutionary inference of the transmission network of the 2014 highly pathogenic Avian Influenza H5N2 outbreak in British Columbia, Canada

The first North American outbreak of highly pathogenic avian influenza (HPAI) involving a virus of Eurasian A/goose/Guangdong/1/1996 (H5N1) lineage began in the Fraser Valley of British Columbia, Canada in late November 2014. A total of 11 commercial and 1 non-commercial (backyard) operations were infected before the outbreak was terminated. Control measures included movement restrictions that were placed on a total of 404 individual premises, 150 of which were located within a 3 km radius of an infected premise(s) (IP). A complete epidemiological investigation revealed that the source of this HPAI H5N2 virus for 4 of the commercial IPs and the single non-commercial IP likely involved indirect contact with wild birds. Three IPs were associated with the movement of birds or service providers and localized/environmental spread was suspected as the source of infection for the remaining 4 IPs. Viral phylogenies, as determined by Bayesian Inference and Maximum Likelihood methods, were used to validate the epidemiologically inferred transmission network. The phylogenetic clustering of concatenated viral genomes and the median-joining phylogenetic network of the viruses supported, for the most part, the transmission network that was inferred by the epidemiologic analysis

Ecology, Biology and Genetics of <em>Millepora</em> Hydrocorals on Coral Reefs

Coral reefs are one of the most productive and diverse ecosystems on Earth. However, climate warming is occurring at an unprecedented rate and has negatively affected coral reefs worldwide. Evaluating the life history of reef-building species carries important implications for coral reef conservation. This chapter examines the taxonomy, biogeography, ecology, symbiosis, morphology and reproductive biology of Millepora hydrocorals, an important but relatively unstudied component of coral reefs. An emphasis is also placed on the influence of variable reef environments on Millepora life history traits, providing a fascinating opportunity to study the interplay between ecology and evolution. Special attention is given to ecological and evolutionary benefits of asexual versus sexual reproduction in the maintenance of genetic and phenotypic diversity. Lastly, this chapter discusses whether life-history strategies of Millepora hydrocorals and tolerance to different stressors can influence their ability to adapt and survive to future climate change, and other natural and anthropogenic disturbances

Eliciting Awe in the Spectator: The Case of a Dhrupad-Based Dance Performance

This paper describes “Kalos, eîdos, skopeîn,” an immersive Dhrupad-based dance installation designed to elicit feelings of awe in the spectators, in a real-life artistic context. This study used a mixed-methods approach in order to explore spectators’ awe experience (N=45), using specific scales and interpretative phenomenological analysis. Results suggested that “Kalos, eîdos, skopeîn,” with its combination of nature motifs and the slow dance-walk associated with the Dhrupad music in the choreography, was able to produce awe-related moments in some spectators and inspire a degree of positive emotions. Our qualitative results viewed awe explicitly as a positive emotion and showed that generally the spectator narratives, involving the whole performance, were based on modified states of consciousness. Three themes emerged: the main theme is “A rich experience of modified states of consciousness” involving the whole performance, and two interconnected sub-themes “Captivated by the slowness of the dancers” associated with the slow movement and “I can still hear the mantra in my head” in rapport with Dhrupad music. This study was carried out as part of the Canadian FRQSC/FCI Project (2019-RC2-260306)

Eliciting Awe in the Spectator: The Case of a Dhrupad-Based Dance Performance

This paper describes “Kalos, eîdos, skopeîn,” an immersive Dhrupad-based dance installation designed to elicit feelings of awe in the spectators, in a real-life artistic context. This study used a mixed-methods approach in order to explore spectators’ awe experience (N=45), using specific scales and interpretative phenomenological analysis. Results suggested that “Kalos, eîdos, skopeîn,” with its combination of nature motifs and the slow dance-walk associated with the Dhrupad music in the choreography, was able to produce awe-related moments in some spectators and inspire a degree of positive emotions. Our qualitative results viewed awe explicitly as a positive emotion and showed that generally the spectator narratives, involving the whole performance, were based on modified states of consciousness. Three themes emerged: the main theme is “A rich experience of modified states of consciousness” involving the whole performance, and two interconnected sub-themes “Captivated by the slowness of the dancers” associated with the slow movement and “I can still hear the mantra in my head” in rapport with Dhrupad music. This study was carried out as part of the Canadian FRQSC/FCI Project (2019-RC2-260306)

Protein-coding variants implicate novel genes related to lipid homeostasis contributing to body-fat distribution.

Body-fat distribution is a risk factor for adverse cardiovascular health consequences. We analyzed the association of body-fat distribution, assessed by waist-to-hip ratio adjusted for body mass index, with 228,985 predicted coding and splice site variants available on exome arrays in up to 344,369 individuals from five major ancestries (discovery) and 132,177 European-ancestry individuals (validation). We identified 15 common (minor allele frequency, MAF ≥5%) and nine low-frequency or rare (MAF &lt;5%) coding novel variants. Pathway/gene set enrichment analyses identified lipid particle, adiponectin, abnormal white adipose tissue physiology and bone development and morphology as important contributors to fat distribution, while cross-trait associations highlight cardiometabolic traits. In functional follow-up analyses, specifically in Drosophila RNAi-knockdowns, we observed a significant increase in the total body triglyceride levels for two genes (DNAH10 and PLXND1). We implicate novel genes in fat distribution, stressing the importance of interrogating low-frequency and protein-coding variants