La production de biodiesel à partir des microalgues ayant un métabolisme hétérotrophe

Le secteur des transports est fortement dépendant des sources d’énergie fossiles. Face à l’éventuel épuisement des ressources, à la fluctuation importante des prix ainsi qu’à la pollution engendrée par leur utilisation, plusieurs alternatives ont été identifiées. La production de biodiesel d’origine microalgale présente plusieurs avantages dont l’importante productivité en biomasse et en huile ainsi que la possibilité de les cultiver sur des terres non arables. Étant donné que la croissance des microalgues de métabolisme hétérotrophe est indépendante du rayonnement solaire, il s’agit d’une option intéressante pour le Québec. Cette production pourrait être réalisée, dans un premier temps, par l’utilisation de résidus agricoles. Toutefois, l’analyse des aspects technologiques, économiques et environnementaux permet de constater que plusieurs efforts de recherche et développement devront être fournis afin de permettre une production d’algocarburants à l’échelle

Les manifestations d’autodétermination par les élèves ayant participé à la TÉVA sur les plans scolaire, professionnel et personnel

Cet essai s’intéresse à l’autonomie des jeunes adultes ayant un handicap moteur, physique, sensoriel ou intellectuel et qui ont participé à la démarche de la transition de l’école à la vie active (TÉVA). L’objectif de l’essai est de répertorier les manifestations d’autodétermination dans leur vie professionnelle, scolaire et personnelle. Le contenu des 23 entrevues conduites auprès d’élèves ayant participé à la TÉVA ou de leurs proches dans le cadre d’une étude de Bourdon et Lessard (2015) portant sur la modélisation de la démarche TÉVA en Estrie a été analysé afin d’en extraire les manifestations d’autodétermination. L’analyse thématique des entrevues a permis d’identifier des manifestations d’autodétermination issues d’une régulation externe, d’une régulation introjectée et d’une régulation identifiée. Les résultats obtenus révèlent que les jeunes adultes ayant participé à la TÉVA semblent avoir une bonne connaissance d’eux-mêmes, de leurs intérêts scolaires et professionnels. En contrepartie, le sentiment de compétence, la fierté personnelle et la connaissance des actions à poser pour atteindre leurs objectifs semblent se présenter moins fréquemment en termes de manifestation d’autodétermination chez les jeunes adultes de l’échantillon. Dans peu de cas, les élèves ont rapporté avoir entamé de leur propre chef des démarches pour obtenir un milieu de stage pour lequel ils entretenaient de l’intérêt. L'analyse des entrevues a également révélé que la conseillère ou le conseiller d'orientation ne semble pas être une professionnelle ou un professionnel particulièrement sollicité pour soutenir les élèves en difficulté dans l'élaboration d'un projet professionnel. Bien que l’implication de la famille et du milieu scolaire des jeunes à propos de la transition à la vie adulte et de l’élaboration de projets soit sans aucun doute essentielle, les compétences du conseiller d’orientation en matière d’accompagnement des élèves dans l’élaboration et la mise en œuvre d’un projet scolaire ou professionnel pourraient être également mises à profit pour mieux préparer et accompagner les jeunes adultes dans leur transition. Ainsi, les données analysées dans le cadre de cet essai indiquent qu’il y a une place à prendre pour les conseillers d’orientation dans le soutien des élèves vivant avec un handicap

Conception de médication à libération contrôlée par impression tridimensionnelle

Ce mémoire présente les travaux portant sur le développement d’un modèle de fabrication de dispositifs pharmaceutiques constitués de matrices de polymères thermoplastiques pouvant relarguer des composés selon différentes cinétiques. La méthode de fabrication repose sur la technologie d’impression tridimensionnelle (3D), conjointement à l’extrusion de fondus. Avec cette dernière, un filament pharmaceutique imprimable en 3D – dans lequel un composé modèle est incorporé – est conçu. Afin d’évaluer la modulabilité du relargage du dispositif imprimé en fonction de son contenu, les filaments sont faits à partir de mélanges contenant différents excipients pharmaceutiques. Ceux-ci sont connus pour leur plus ou moins grande capacité de retarder le relargage ou de le cibler selon un endroit précis au sein du système gastro-intestinal – en fonction du pH. Le composé modèle utilisé dans cette étude est la caféine et les excipients choisis sont des polymères de poly(vinylpyrrolidone), un mélange de poly(vinylpyrrolidone) et de poly(acétate de vinyle) (20 :80) et le poly(acide méthacrylique-co- méthacrylate de méthyle) de ratios (1 :1) et (1 :2). L’extrudeuse utilisée est le modèle HAAKE MiniLab CTW Rheomex 5 de Thermo Scientific et l’imprimante 3D est System 30M de Hyrel 3D. Les fichiers de stéréo lithographie (.stl) utilisés par le logiciel d’impression sont produits à l’aide de FreeCAD, logiciel de dessin assisté par ordinateur. Des tests de dissolutions sont effectués afin d'évaluer le relargage à partir des dispositifs imprimés

Social contagion and high school dropout : the role of friends, romantic partners, and siblings

Social contagion theories suggest that adolescents in relationships with same-age high school dropouts should be at a greater risk of dropping out themselves. Yet, few studies have examined this premise, and none have considered all potentially influential same-age intimates, focusing instead on only either friends or siblings. Moreover, a key influence in adolescents’ social worlds, romantic partners, has been ignored. The goal of this study was to provide a comprehensive view of dropout contagion by considering occurrences of dropout among friends, siblings, and romantic partners. Data came from a sample of Canadian adolescents (N = 545) comprising one third of high school dropouts; a second third of carefully matched at-risk but persevering schoolmates; and a last third of average, not-at-risk students. As predicted, adolescents were at greater risk of dropping out when a member of their network had recently left school (i.e., in the past year, OR = 3.11; 95% CI [1.78, 6.27]), with independent associations of nontrivial sizes for occurrences of dropout among friends, romantic partners, and siblings (ORs between 1.97 [95% CI 1.25, 3.41] and 3.12 [95% CI 1.23, 11.0]). Moreover, adolescents seemed particularly at risk of quitting school (OR = 4.88; 95% CI [2.54, 12.5]) when their networks included more than one type of same-age intimate (e.g., a friend and a sibling) who had recently dropped out. Findings suggest that social contagion of dropout is a pervasive phenomenon in low-income schools and that prevention programs should target adolescents with same-age intimates who have recently left school

La nouvelle Commission québécoise des relations du travail (1988)

Après avoir résumé les motifs allégués par le ministre du Travail du Québec au soutien du projet de loi 30 et des objectifs qu'il y visait, les auteurs analysent les changements institutionnels apportes par cette loi, précisent le rôle et le mandat de la Commission et étudient en détail son fonctionnement et ses pouvoirs.In this article the authors first summarize the reasons put forward by the Quebec Minister of Labour to justify Bill 30 and what the amendments to the Labour Code are intended to accomplish. They then analyse the changes brought about by the new law in the decision-making bodies: they discuss those bodies which will be abolished and the transfer of jurisdiction to other tribunals including the new Labour Relations Board which will be created. The authors next evaluate the role and mandate of the new Board and they draw a distinction between those areas where the Board alone will have jurisdiction and those where its role will be concurrent with another body. There is particular emphasis on unfair labour practice complaints since the Board will have exclusive jurisdiction over a whole new range of such complaints. The major part of the article consists of a detailed study of the functions and powers of the new Board. Here the authors begin by reviewing how the Board becomes seized of a matter: who has standing to file applications and be heard, what are the time limits and what procedural requirements must be met. Once seized of the matter but prior to the hearing, the Board is called upon to perform two distinct functions: investigation and mediation. In this context, the authors attempt to answer these questions: Who will act on the Board's behalf to investigate the facts and what are the precise powers of the investigator and who will act on the Board's behalf to mediate between the parties and at what point is such mediation likely to occur?The hearing itself is then considered as well as the particular problem of who can act as a decision maker. Also discussed is the legality of the provision of the new law whereby a hearing does not have to be held and can be dispensed with by the expedient of allowing each party the opportunity to make representations without the possibility of cross-examining the opposite party. The new law allows the Board to examine matters «according to the mode of proof it deems appropriate» and the precise meaning of this phrase is discussed. The Board's remedial powers come under close scrutiny in the article, especially the power to order injunctive-type relief in the form of cease and desist orders. It is pointed out that the Board may refuse to intervene in certain cases and that it may take cognizance of an undertaking to conform to the Code instead of rendering a decision. Since the Board must give written reasons for any decision which terminates a matter, consideration is given to how the expressions «reasons» and «terminates a matter» are likely to be interpreted. The Board has the power to revoke and review its own decision and the circumstances giving rise to such a procedure are examined. Finally, the authors look at the manner in which the Board's decisions become enforceable. By way of conclusion, the authors list the additional areas in which the Board will have the power to intervene and consider the consequence of such increased intervention by the Board. They also indicate how they believe employers and unions will have to adjust and change some long-standing practices. The article ends with a warning of the problems that could arise if Bill 30 is not implemented and applied with good judgment and insight

The Prostanoid 15-Deoxy-D 12,14 -Prostaglangin-J 2 Reduces Lung Inflammation and Protects Mice Against Lethal Influenza Infection

Background. Growing evidence indicates that influenza pathogenicity relates to altered immune responses and hypercytokinemia. Therefore, dampening the excessive inflammatory response induced after infection might reduce influenza morbidity and mortality. Methods. Considering this, we investigated the effect of the anti-inflammatory molecule 15-deoxy-D 12,14 -prostaglandin J 2 (15d-PGJ 2 ) in a mouse model of lethal influenza infection. Results. Administration of 15d-PGJ 2 on day 1 after infection, but not on day 0, protected 79% of mice against lethal influenza infection. In addition, this treatment considerably reduced the morbidity associated with severe influenza infection. Our results also showed that treatment with 15d-PGJ 2 decreased influenza-induced lung inflammation, as shown by the diminished gene expression of several proinflammatory cytokines and chemokines. Unexpectedly, 15d-PGJ 2 also markedly reduced the viral load in the lungs of infected mice. This could be attributed to maintained type I interferon gene expression levels after treatment. Interestingly, pretreatment of mice with a peroxisome proliferator-activated receptor gamma (PPARc) antagonist before 15d-PGJ 2 administration completely abrogated its protective effect against influenza infection. Conclusions. Our results demonstrate for the first time that treatment of mice with 15d-PGJ 2 reduces influenza morbidity and mortality through activation of the PPARc pathway. PPARc agonists could thus represent a potential therapeutic avenue for influenza infections

Effets du nettoyage et du conditionnement sur la dégradation des PVC plastifiés

Le polychlorure de vinyle plastifié est un polymère synthétique, largement utilisé depuis le milieu du xxe siècle et jusqu’à nos jours, pour la production d’œuvres d’art et d’objets. Son état de conservation est souvent médiocre en raison de la migration des plastifiants. L’étude de l’impact du nettoyage et du mode de conditionnement de PVC vieillis naturellement en environnement muséal sur leur évolution permet d’envisager des conditions de conservation préventives et curatives optimales afin d’en limiter les dégradations.Plasticized polyvinyl chloride is a synthetic polymer, widely used from the mid-20th century until today in the production of artworks and artefacts. Its condition is often mediocre owing to the migration of plasticizers. The study of the impact of cleaning and conditioning on the evolution of naturally ageing PVCs in a museum environment has enabled us to envisage optimum conditions for preventive conservation so as to mitigate the degradation process

SARS-CoV-2 spike antigen-specific B cell and antibody responses in pre-vaccination period COVID-19 convalescent males and females with or without post-covid condition

BackgroundFollowing SARS-CoV-2 infection a significant proportion of convalescent individuals develop the post-COVID condition (PCC) that is characterized by wide spectrum of symptoms encompassing various organs. Even though the underlying pathophysiology of PCC is not known, detection of viral transcripts and antigens in tissues other than lungs raise the possibility that PCC may be a consequence of aberrant immune response to the viral antigens. To test this hypothesis, we evaluated B cell and antibody responses to the SARS-CoV-2 antigens in PCC patients who experienced mild COVID-19 disease during the pre-vaccination period of COVID-19 pandemic.MethodsThe study subjects included unvaccinated male and female subjects who developed PCC or not (No-PCC) after clearing RT-PCR confirmed mild COVID-19 infection. SARS-CoV-2 D614G and omicron RBD specific B cell subsets in peripheral circulation were assessed by flow cytometry. IgG, IgG3 and IgA antibody titers toward RBD, spike and nucleocapsid antigens in the plasma were evaluated by ELISA.ResultsThe frequency of the B cells specific to D614G-RBD were comparable in convalescent groups with and without PCC in both males and females. Notably, in females with PCC, the anti-D614G RBD specific double negative (IgD-CD27-) B cells showed significant correlation with the number of symptoms at acute of infection. Anti-spike antibody responses were also higher at 3 months post-infection in females who developed PCC, but not in the male PCC group. On the other hand, the male PCC group also showed consistently high anti-RBD IgG responses compared to all other groups.ConclusionsThe antibody responses to the spike protein, but not the anti-RBD B cell responses diverge between convalescent males and females who develop PCC. Our findings also suggest that sex-related factors may also be involved in the development of PCC via modulating antibody responses to the SARS-CoV-2 antigens

SARS-CoV-2 spike antigen-specific B cell and antibody responses in pre-vaccination period COVID-19 convalescent males and females with or without post-covid condition

Background Following SARS-CoV-2 infection a significant proportion of convalescent individuals develop the post-COVID condition (PCC) that is characterized by wide spectrum of symptoms encompassing various organs. Even though the underlying pathophysiology of PCC is not known, detection of viral transcripts and antigens in tissues other than lungs raise the possibility that PCC may be a consequence of aberrant immune response to the viral antigens. To test this hypothesis, we evaluated B cell and antibody responses to the SARS-CoV-2 antigens in PCC patients who experienced mild COVID-19 disease during the pre-vaccination period of COVID-19 pandemic. Methods The study subjects included unvaccinated male and female subjects who developed PCC or not (No-PCC) after clearing RT-PCR confirmed mild COVID-19 infection. SARS-CoV-2 D614G and omicron RBD specific B cell subsets in peripheral circulation were assessed by flow cytometry. IgG, IgG3 and IgA antibody titers toward RBD, spike and nucleocapsid antigens in the plasma were evaluated by ELISA. Results The frequency of the B cells specific to D614G-RBD were comparable in convalescent groups with and without PCC in both males and females. Notably, in females with PCC, the anti-D614G RBD specific double negative (IgD-CD27-) B cells showed significant correlation with the number of symptoms at acute of infection. Anti-spike antibody responses were also higher at 3 months post-infection in females who developed PCC, but not in the male PCC group. On the other hand, the male PCC group also showed consistently high anti-RBD IgG responses compared to all other groups. Conclusions The antibody responses to the spike protein, but not the anti-RBD B cell responses diverge between convalescent males and females who develop PCC. Our findings also suggest that sex-related factors may also be involved in the development of PCC via modulating antibody responses to the SARS-CoV-2 antigens