232 research outputs found
« Changer la vie » ou « changer le monde » ?
Rédigés pendant une période où les femmes du Québec venaient de gagner le droit de vote et où les rôles féminins subissaient des changements majeurs grâce aux besoins de l'industrie de guerre, Le Survenant et Bonheur d'occasion représentent un moment dramatique dans « l'émergence du féminin» dans la tradition du roman québécois. Sans vouloir contredire la nouveauté radicale de cet apport analysé dans son ouvrage antérieur {Écrire dans la maison du père, 1988), l'auteure se penche davantage sur l'aspect de transition des deux romans, sur les empêchements du féminin qu'on y décèle, tant au niveau de la forme que du contenu, notamment la centralité dans chacun des deux d'un personnage masculin (le Survenant, Emmanuel Létourneau) qui fonctionne comme porte-parole des idées de la romancière et représente le « rédempteur » de ce monde où les anciennes valeurs sont en déroute et où, malgré la persistance de certains rituels rassurants, les personnages sont en proie à une angoisse spirituelle et sociale. Par l'utilisation de ces personnages plus ou moins « androgynes », les deux romancières confèrent une autorité masculine aux valeurs féminines qu'elles cherchent à transmettre
Derrière la femme‑objet : la représentation de Muriel Guilbault dans Beauté baroque
Le roman Beauté baroque de Claude Gauvreau est un « récit de vie » biographique et autobiographique où l'auteur raconte l'histoire de la vie de Muriel Guilbault telle que la lui a confiée la jeune comédienne avant sa mort en 1952. En même temps, Gauvreau fait du personnage de 1'« actrice » dans son récit une incarnation de l'idéal surréaliste de la « femme-enfant », force de la nature et voie d'accès à un domaine transcendant et surrationnel. La présente étude est une tentative pour extraire de cette image idéalisée et quelque peu misogyne du personnage un portrait de la « vraie » Muriel Guilbault et de sa relation avec Claude Gauvreau.Claude Gauvreaus novel Beauté baroque is an example of "life writing", both biographical and autobiographical, in which the author recounts the story of the life of the young actress Muriel Guilbault as she confided it to him in the period preceding her 1952 suicide. But the female protagonist is also modelled on the Surrealist ideal of the "woman-child" who represents a force of nature and a mediation with the realm of the surrational and the transcendant. This study is an attempt to extricate a portrait of the real Muriel Guilbault and her relationship with Claude Gauvreaufrom the idealized and somewhat misogynist image projected onto her in the novel
Structural and dynamic properties of alpha, omega-dibromoalkanes and other guest molecules in their urea inclusion compounds
The work described in this thesis focuses on the urea inclusion compounds of α, ω-dibromo-n-alkanes: Br(CH₂)[sub]nBr/urea, where n=7-10. The structural and dynamic properties of the host and guest have been studied using complementary techniques. Photographic single crystal x-ray diffraction shows that, in the regions of three- dimensional guest molecular ordering, there is a well-defined offset, Δg, along the channel axis, c, between guest molecules in adjacent channels. Δg is exactly one-third of the periodic repeat distance along c of the basic guest structure: this represents a new mode of interchannel guest ordering in urea inclusion compounds. Raman spectroscopy shows that the 'bulk' conformation of the guest molecules is the linear, trans, extended form, but that there is a small, but measurable, proportion of Br end-groups in the gauche conformation. Incoherent quasielastic neutron scattering indicates that the guest molecules undergo two motions on the picosecond time-scale, at sufficiently high temperature: translations along the channel axis and reorientations about the channel axis. These motions are successfully modelled as, respectively, continuous linear diffusion between two impermeable boundaries and uniaxial rotational diffusion in a one-fold cosine potential. Deuterium nuclear magnetic resonance spectra are shown, via simulations, to be consistent with a 180° flipping motion of the urea molecules about their C=O axes, occurring on the microsecond time-scale at room temperature. This technique also provides confirmation of guest molecular motion. The structure of 1,6-dibromohexane/urea is found to differ from that of the other a,w-dibromoalkane/urea inclusion compounds studied: crystal structure determination shows that it is monoclinic, and that the host and guest structures are commensurate with one another. Raman spectroscopy confirms that the Br end-groups are exclusively in the gauche conformation. The urea inclusion compounds of various other guest molecules have also been investigated briefly. The complementary nature of the techniques used is crucial in establishing a complete picture of the structure and dynamics of all these compounds
Linking Phenology and Biomass Productivity in South Dakota Mixed-Grass Prairie
Assessing the health of rangeland ecosystems based solely on annual biomass production does not fully describe the condition of the plant community; the phenology of production can provide inferences about species composition, successional stage, and grazing impacts. We evaluated the productivity and phenology of western South Dakota mixed-grass prairie in the period from 2000 to 2008 using the normalized difference vegetation index (NDVI). The NDVI is based on 250-m spatial resolution Moderate Resolution Imaging Spectroradiometer (MODIS) satellite imagery. Growing-season NDVI images were integrated weekly to produce time-integrated NDVI (TIN), a proxy of total annual biomass production, and integrated seasonally to represent annual production by cool- and warm-season species (C3 and C4, respectively). Additionally, a variety of phenological indicators including cool-season percentage of TIN were derived from the seasonal profiles of NDVI. Cool-season percentage and TIN were combined to generate vegetation classes, which served as proxies of the conditions of plant communities. TIN decreased with precipitation from east to west across the study area. However, the cool-season percentage increased from east to west, following patterns related to the reliability (interannual coefficient of variation [CV]) and quantity of midsummer precipitation. Cool-season TIN averaged 76.8% of the total TIN. Seasonal accumulation of TIN corresponded closely (R2 . 0.90) to that of gross photosynthesis data from a carbon flux tower. Field-collected biomass and community composition data were strongly related to TIN and cool-season percentage. The patterns of vegetation classes were responsive to topographic, edaphic, and land management influences on plant communities. Accurate maps of biomass production, cool- and warm-season composition, and vegetation classes can improve the efficiency of land management by facilitating the adjustment of stocking rates and season of use to maximize rangeland productivity and achieve conservation objectives. Further, our results clarify the spatial and temporal dynamics of phenology and TIN in mixed-grass prairie
Effects of Prairie Dogs and Cattle on Vegetation Disappearance on Prairie Dog Towns in Mixed-Grass Prairie
Quantitative data is lacking on competition between prairie dogs and cattle for forage on mixed-grass prairie pastures. The objective of this study was to determine the disappearance of vegetation attributable to cattle and prairie dogs on pastures with prairie dog towns. During the summers of 2002 and 2003, biomass estimates were made periodically on three mixed-grass prairie pastures in south central South Dakota that had varying degrees of prairie dog town coverage (percent of pasture area). Two types of grazing exclosures were established. Cattle exclosures allowed grazing by prairie dogs only. Cattle/prairie dog exclosures excluded both herbivores. Permanent plots outside cages were established that allowed grazing by both species. Biomass estimates on individual vegetation species were obtained both inside the exclosures and on permanent plots outside the exclosures two times in 2002 and 2003. Forage removed was estimated and compared for cattle alone, prairie dogs alone, and cattle and prairie dogs together in each year. Forage removed by prairie dogs on the on-town sites was nearly three times as great as forage removed by cattle on the on-town sites for the June and July sampling periods. Cattle removed two times more forage on off-town sites than on on-town sites. Total forage removed on on-town sites (cattle + prairie dogs) was almost two times greater than on off-town sites. Livestock forage was significantly reduced on prairie dog towns compared to unoccupied sites. Classic carrying capacity calculations overestimate forage availability when prairie dog towns are present. Stocking rates on pastures with prairie dog towns should be adjusted to account for forage disappearance due to prairie dogs
Forecasting Forage Yield on Clayey Ecological Sites in Western South Dakota using Weather Data
The ability to forecast annual forage yield from weather data would be useful for making appropriate adjustments to stocking rates in order to achieve or maintain desired plant communities. Our objective was to determine the relationship between weather variables and annual forage yield from three distinct plant communities on clayey ecological sites in western South Dakota. Forage yield and weather data were collected from 1945 through 1960 at the Cottonwood Range and Livestock Research Station, in western South Dakota. Pastures stocked at 0.25, 0.40, and 0.60 AUM/acre from 1942 to 1960 developed into western wheatgrass-dominated, western wheatgrass-shortgrass co-dominated, and shortgrass dominated plant communities, respectively. Forage data were compiled from previously reported data and raw data. Spring (April-June) precipitation, the last calendar day that the minimum temperature was 30oF or below, and previous year’s spring precipitation were best predictors (R2 = 0.81) of forage yield in western wheatgrass dominated plant communities. Spring precipitation and the last calendar day that the minimum temperature was 30oF or below were best predictors (R2 = 0.69) of forage yield in western wheatgrass-shortgrass co-dominated plant communities. Spring precipitation was the best predictor (R2 = 0.52) of forage yield in shortgrass dominated plant communities. In western South Dakota, managers of these plant communities can make reliable estimates of annual forage yield by the end of June using precipitation and temperature measurements
The histone deacetylase inhibitor, romidepsin, as a potential treatment for pulmonary fibrosis
Idiopathic pulmonary fibrosis (IPF) is a progressive disease that usually affects elderly people. It has a poor prognosis and there are limited therapies. Since epigenetic alterations are associated with IPF, histone deacetylase (HDAC) inhibitors offer a novel therapeutic strategy to address the unmet medical need. This study investigated the potential of romidepsin, an FDA-approved HDAC inhibitor, as an anti-fibrotic treatment and evaluated biomarkers of target engagement that may have utility in future clinical trials. The anti-fibrotic effects of romidepsin were evaluated both in vitro and in vivo together with any harmful effect on alveolar type II cells (ATII). Bronchoalveolar lavage fluid (BALF) from IPF or control donors was analyzed for the presence of lysyl oxidase (LOX). In parallel with an increase in histone acetylation, romidepsin potently inhibited fibroblast proliferation, myofibroblast differentiation and LOX expression. ATII cell numbers and their lamellar bodies were unaffected. In vivo, romidepsin inhibited bleomycin-induced pulmonary fibrosis in association with suppression of LOX expression. LOX was significantly elevated in BALF of IPF patients compared to controls. These data show the anti-fibrotic effects of romidepsin, supporting its potential use as novel treatment for IPF with LOX as a companion biomarker for evaluation of early on-target effects
HER3 and downstream pathways are involved in colonization of brain metastases from breast cancer
Introduction: Metastases to the brain from breast cancer have a high mortality, and basal-like breast cancers have a propensity for brain metastases. However, the mechanisms that allow cells to colonize the brain are unclear.Methods: We used morphology, immunohistochemistry, gene expression and somatic mutation profiling to analyze 39 matched pairs of primary breast cancers and brain metastases, 22 unmatched brain metastases of breast cancer, 11 non-breast brain metastases and 6 autopsy cases of patients with breast cancer metastases to multiple sites, including the brain.Results: Most brain metastases were triple negative and basal-like. the brain metastases over-expressed one or more members of the HER family and in particular HER3 was significantly over-expressed relative to matched primary tumors. Brain metastases from breast and other primary sites, and metastases to multiple organs in the autopsied cases, also contained somatic mutations in EGFR, HRAS, KRAS, NRAS or PIK3CA. This paralleled the frequent activation of AKT and MAPK pathways. in particular, activation of the MAPK pathway was increased in the brain metastases compared to the primary tumors.Conclusions: Deregulated HER family receptors, particularly HER3, and their downstream pathways are implicated in colonization of brain metastasis. the need for HER family receptors to dimerize for activation suggests that tumors may be susceptible to combinations of anti-HER family inhibitors, and may even be effective in the absence of HER2 amplification (that is, in triple negative/basal cancers). However, the presence of activating mutations in PIK3CA, HRAS, KRAS and NRAS suggests the necessity for also specifically targeting downstream molecules.Ludwig Institute of Cancer ResearchNational Breast Cancer FoundationUniv Queensland, Clin Res Ctr, Brisbane, Qld 4029, AustraliaQueensland Inst Med Res, Brisbane, Qld 4006, AustraliaUniversidade Federal de SĂŁo Paulo, EPM, Dept Anat Patol, BR-04024000 SĂŁo Paulo, BrazilGriffith Univ, Brisbane, Qld 4011, AustraliaUniv Queensland, Ctr Magnet Resonance, Brisbane, Qld 4072, AustraliaEijkman Inst, Jakarta 10430, IndonesiaInst Nacl Canc, Dept Patol, BR-20230130 Rio de Janeiro, BrazilLab Salomao & Zoppi, Dept Patol, BR-04104000 SĂŁo Paulo, BrazilCharles Univ Prague, Fac Med, Dept Pathol, Plzen 30605, Czech RepublicUniv Sydney, Inst Clin Pathol & Med Res, Sydney W Area Hlth Serv, Sydney, NSW 2145, AustraliaUniv Sydney, Westmead Millennium Inst, Sydney W Area Hlth Serv, Sydney, NSW 2145, AustraliaPeter MacCallum Canc Ctr, Dept Pathol, Melbourne, Vic 3002, AustraliaUniv Queensland, Queensland Brain Inst, Brisbane, Qld 4072, AustraliaRoyal Brisbane & Womens Hosp, Brisbane, Qld 4029, AustraliaUniversidade Federal de SĂŁo Paulo, EPM, Dept Anat Patol, BR-04024000 SĂŁo Paulo, BrazilWeb of Scienc
- …