15 research outputs found
Social cognition evaluation in interaction situation in traumatic brain injury
La cognition sociale, i.e. notre capacitĂ© Ă attribuer des Ă©tats mentaux Ă autrui et Ă identifier ses Ă©motions, est souvent perturbĂ©e dans certaines pathologies telles que le traumatisme crĂąnien (TC). Cette capacitĂ© est traditionnellement Ă©valuĂ©e Ă lâaide de tĂąches sous format « papier-crayon » nâimpliquant pas le participant dans une situation dâinteraction sociale. Pourtant, la cognition sociale est fondamentale dans nos interactions sociales car elle nous permet de comprendre le discours et le comportement dâautrui. Ainsi, dans ce travail de thĂšse, nous avons Ă©valuĂ© les capacitĂ©s dâattribution dâĂ©tats mentaux et de reconnaissance Ă©motionnelle de personnes ayant subi un TC Ă lâaide de tĂąches les impliquant activement dans une situation de communication (tĂąche de communication rĂ©fĂ©rentielle et tĂąche EViCog), ce qui nâa jamais Ă©tĂ© fait dans cette pathologie. La tĂąche EViCog (Evaluation de la cognition sociale en interaction virtuelle), crĂ©Ă©e pour cette Ă©tude, permet dâavoir des conversations audio-visuelles avec des humains virtuels, qui expriment des Ă©motions et produisent du discours nĂ©cessitant dâinfĂ©rer leurs Ă©tats mentaux. Les rĂ©sultats ont montrĂ© que les difficultĂ©s des personnes TC Ă©taient encore plus importantes pour la tĂąche en situation dâinteraction (tĂąche EViCog) par rapport Ă des tĂąches traditionnelles au format « papier-crayon ». Par ailleurs, en situation dâinteraction, les performances de cognition sociale semblent dĂ©pendre en partie des capacitĂ©s mnĂ©siques (mĂ©moire autobiographique et du contexte), ainsi que des fonctions exĂ©cutives, alors que pour les tĂąches traditionnelles, les performances ne seraient expliquĂ©es que par certaines capacitĂ©s exĂ©cutives.Social cognition, i.e. the ability to attribute mental states to others and to identify emotions, is often impaired in various pathologies, such as traumatic brain injury (TBI). This ability is traditionally assessed with âpaper-and-pencilâ tasks that do not involve the participant in a social interaction situation. However, social cognition is central in our daily social interactions, as it helps us understand othersâ speech and behavior. Thus, in this study, we assessed mental state attribution and emotion recognition abilities of TBI participants, using tasks that involve the participant in a communication situation (referential communication task and EViCog task). The EViCog task (social cognition evaluation in virtual interaction), designed for this research, provides audio-visual conversations with virtual humans, which express emotions and produce speech requiring mental state inference. The results showed that the difficulties of the TBI participants were even more important for the task in interaction situation (EViCog task) compared to traditional tasks in paper-and-pencil format. Moreover, in interaction situation, social cognition performance seemed to rely on mnemonic abilities (autobiographical memory and context memory), and on executive functions, while for traditional tasks, performances were only explained by some executive abilities
Les asiles d'aliénés de la province de Québec et leurs détracteurs
Comprend du texte en anglais.Collection Chagno
La mouche ou la chrysomĂšle des patates (chrysomela decemlineata) et le moyen d'en combattre les ravages
Collection Chagno
Feedback Regulation of Thyrotropin-Releasing Hormone Gene Expression by Thyroid Hormone in the Caudal Raphe Nuclei in Rats**This work was supported by NIH Grants DK-50255 (H.Y.), DK-30110 (Y.T.), and DK-41301, Pilot and Feasibility Award (to H.Y.).
The RAPID Method for Blood Processing Yields New Insight in Plasma Concentrations and Molecular Forms of Circulating Gut Peptides
The RAPID Method for Blood Processing Yields New Insight in Plasma Concentrations and Molecular Forms of Circulating Gut Peptides
Corticotropin-Releasing Factor-Overexpressing Mice Exhibit Reduced Neuronal Activation in the Arcuate Nucleus and Food Intake in Response to Fasting
Corticotropin-releasing factor (CRF) overexpressing (OE) mice are a genetic model that exhibits features of chronic stress. We investigated whether the adaptive feeding response to a hypocaloric challenge induced by food deprivation is impaired under conditions of chronic CRF overproduction. Food intake response to a 16-h overnight fast and ip injection of gut hormones regulating food intake were compared in CRF-OE and wild type (WT) littermate mice along with brain Fos expression, circulating ghrelin levels, and gastric emptying of a nonnutrient meal. CRF-OE mice injected ip with saline showed a 47 and 44% reduction of 30-min and 4-h cumulative food intake response to an overnight fast, respectively, compared with WT. However, the 30-min food intake decrease induced by ip cholecystokinin (3 ÎŒg/kg) and increase by ghrelin (300 ÎŒg/kg) were similar in CRF-OE and WT mice. Overnight fasting increased the plasma total ghrelin to similar levels in CRF-OE and WT mice, although CRF-OE mice had a 2-fold reduction of nonfasting ghrelin levels. The number of Fos-immunoreactive cells induced by fasting in the arcuate nucleus was reduced by 5.9-fold in CRF-OE compared with WT mice whereas no significant changes were observed in other hypothalamic nuclei. In contrast, fasted CRF-OE mice displayed a 5.6-fold increase in Fos-immunoreactive cell number in the dorsal motor nucleus of the vagus nerve and a 34% increase in 20-min gastric emptying. These findings indicate that sustained overproduction of hypothalamic CRF in mice interferes with fasting-induced activation of arcuate nucleus neurons and the related hyperphagic response
Gold Nanoparticle Internal Structure and Symmetry Probed by Unified Small-Angle Xâray Scattering and Xâray Diffraction Coupled with Molecular Dynamics Analysis
Shape and size are known to determine
a nanoparticleâs properties. Hardly ever studied in synthesis,
the internal crystal structure (i.e., particle defects, crystallinity,
and symmetry) is just as critical as shape and size since it directly
impacts catalytic efficiency, plasmon resonance, and orients anisotropic
growth of metallic nanoparticles. Hence, its control cannot be ignored
any longer in todayâs research and applications in nanotechnology.
This study implemented an unprecedented reliable measurement combining
these three structural aspects. The unified small-angle X-ray scattering
and diffraction measurement (SAXS/XRD) was coupled with molecular
dynamics to allow simultaneous determination of nanoparticlesâ
shape, size, and crystallinity at the atomic scale. Symmetry distribution
(icosahedraîžIh, decahedraîžDh, and truncated octahedraîžTOh)
of 2â6 nm colloidal gold nanoparticles synthesized in organic
solvents was quantified. Nanoparticle number density showed the predominance
of Ih, followed by Dh, and little, if any, TOh. This result contradicts
some theoretical predictions and highlights the strong effect of the
synthesis environment on structure stability. We foresee that this
unified SAXS/XRD analysis, yielding both statistical and quantitative
counts of nanoparticlesâ symmetry distribution, will provide
new insights into nanoparticle formation, growth, and assembly
A Comprehensive Study of the Mechanism of Formation of Polyol-Made Hausmannite Nanoparticles: From Molecular Species to Solid Precipitation
This study aims at achieving a better understanding of
the mechanisms
of formation of Mn<sub>3</sub>O<sub>4</sub> nanoparticles prepared
by the polyol process. The role of each reactant is studied, and a
possible scheme of reaction is proposed, involving the activation
of dioxygen by MnÂ(II) species. The growth of the particles (evolution
of the size and concentration of particles) has been followed in solution
by SAXS, and the results have been compared to those obtained by other
techniques on dried powders. The results indicate a decrease of the
number of particles in solution with time together with their enlargement.
A stabilization of the size and number of particles is reached after
a few hours. The shape of the particles then evolves into a truncated
ditetragonal-dipyramidal polyhedron