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See detailVoltaire as a playwright, an off-centered strategy?
Daubercies, Laurence ULg

Conference (2015, March 21)

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See detailRelations internationales et diplomatie à l’époque confessionnelle (1517-1648)
Regibeau, Julien ULg

Conference given outside the academic context (2015)

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See detailLes plus anciens livres latins de poésie: étude codicologiue, paléographique et contextuelle des manuscrits datés du Ier siècle avant notre ère au VIe siècle.
Macedo, Gabriel ULg

Doctoral thesis (2015)

Codicological, paleographic and contextual study of the 34 oldest manuscripts and fragments containing latin poetry.

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See detailBioassessment of trace element contamination of Mediterranean coastal waters using the seagrass Posidonia oceanica
Richir, Jonathan ULg; Salivas-Decaux, Maÿlis; Lafabrie, Céline et al

in Journal of Environmental Management (2015), 150

A large scale survey of the trace element (TE) contamination of Mediterranean coastal waters was performed from the analysis of Ag, As, Cd, Cu, Hg, Ni and Pb in the bioindicator Posidonia oceanica ... [more ▼]

A large scale survey of the trace element (TE) contamination of Mediterranean coastal waters was performed from the analysis of Ag, As, Cd, Cu, Hg, Ni and Pb in the bioindicator Posidonia oceanica, sampled at 110 sites differing by their levels of exposure to contaminants. The holistic approach developed in this study, based on the combined utilization of several complementary monitoring tools, i.e. water quality scale, pollution index and spatial analysis, accurately assessed the TE contamination rate of Mediterranean coastal waters. In particular, the mapping of the TE contamination according to a new proposed 5-level water quality scale precisely outlined the contamination severity along Mediterranean coasts and facilitated interregional comparisons. Finally, the reliability of the use of P. oceanica as bioindicator species was again demonstrated through several global, regional and local detailed case studies. NB: The designations employed and the presentation of the information in thisdocument do not imply the expression of any opinion whatsoever on the part of the authors concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries. [less ▲]

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See detailDouble thermo-responsive hydrogels from poly(vinylcaprolactam) containing diblock and triblock copolymers
Thomassin, Jean-Michel ULg; Mathieu, Kevin ULg; Kermagoret, Anthony ULg et al

in Polymer Chemistry (2015), 6(10), 1856-1864

The thermally-induced gelation and gel properties of concentrated aqueous solutions of double thermoresponsive poly(N-vinylamide)-based di- and triblock copolymers are studied by rheology. The copolymers ... [more ▼]

The thermally-induced gelation and gel properties of concentrated aqueous solutions of double thermoresponsive poly(N-vinylamide)-based di- and triblock copolymers are studied by rheology. The copolymers under investigation, prepared by cobalt-mediated radical polymerization and coupling reactions, are composed of poly(vinylcaprolactam) (PNVCL) blocks and of a statistical poly(vinylcaprolactam-stat-vinylpyrrolidone) segment with a cloud point temperature (TCP) higher than that of PNVCL. Heating the di- and triblock solutions beyond the first phase transition temperature favors gel formation while heating above the second TCP leads to opaque gels without macroscopic demixing. Moduli of the triblock hydrogels are systematically higher than those of the corresponding diblocks, even above the second transition. Rheological data suggest distinct micellar structures for each copolymer architecture: densely packed micelles of diblocks and 3-D networks of bridged micelles for triblocks. Strain sweep experiments also emphasize the positive effect of the micelle bridging on the elasticity and stability of the hydrogels. The formation and properties of the obtained gels are also shown to depend on the copolymer concentration, block length, and composition. Addition of salt also allows us to tune the phase transition temperatures of these double thermoresponsive hydrogels. [less ▲]

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See detailDu travestissement à la traversée. À propos d’un bas-relief romain
Veymiers, Richard ULg

Conference (2015, March 13)

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See detailFrom photons to biomass in green microalgae: fluorimetric and oxymetric studies on the regulation of photosynthetic electron transport
de Marchin, Thomas ULg

Doctoral thesis (2015)

Analyzing the photosynthetic performances of microalgae has become an important topic in view of the ecological importance of these microorganisms and of the growing field of their biotechnological ... [more ▼]

Analyzing the photosynthetic performances of microalgae has become an important topic in view of the ecological importance of these microorganisms and of the growing field of their biotechnological applications. In this thesis, we developed methods which allow effective use of fluorescence and oxygen experimental signals for a more complete analysis of the functioning of the photosynthetic apparatus of green microalgae under different conditions. We applied these methods to analyze the adaptations of the photosynthetic apparatus under selected conditions, especially regarding CO2 supply. In the first part of this work, we applied a fluorescence-based method for determining the PSII antenna size based on the kinetics of the fast chlorophyll a fluorescence transient in presence of DCMU (or DCMU Fluorescence Rise). We then performed a detailed analysis of the different phases of this transient which are associated with different types of PSII formerly described as PSIIalpha and PSIIbeta (PSII heterogeneity). Our results on PSII heterogeneity during a transition from state 2 to state 1 in Chlamydomonas reinhardtii showed for the first time in vivo that this transition correlates with a conversion of PSIIbeta to PSIIalpha. We also discuss the possible relationships between PSIIalpha and PSIIbeta and the PSII mega-, super- and core- complexes described by biochemical studies. In photoautotophic atmospheric conditions, microalgae often have to deal with limited CO2 availability. The unicellular green algae Chlamydomonas reinhardtii can adapt to low CO2 concentration with the inorganic carbon concentration mechanism (CCM). This has been extensively studied in the past. However, other functional adaptations of the photosynthetic apparatus to CO2 limitation have been much less studied. In the second part of this work, we used combined fluorescence-based electron transport and oxygen measurements to evaluate the responses to low and high CO2 in Chlamydomonas reinhardtii grown in photobioreactors at different light intensities. We developed a method to rationalize the relationship between the apparent quantum yields of oxygen evolution and of electron transport at PSII while taking into account the variations in the proportion of energy absorbed by PSII. We used this relationship as a tool to evidence a significant O2-dependent alternative electron transport in low CO2 acclimated cells. We showed that this alternative electron transport can represent up to 60% of the total electron transport in low CO2 cells even upon removal of the CO2 limitation by bicarbonate addition. In contrast, no significant alternative electron transport was detected in high CO2 cells. We suggest that the alternative electron transport to O2 observed in low CO2 cells represents an adaptation that could help to meet the higher ATP demand for the concentration of CO2 by the CCM. In contrast, in high CO2 conditions, the absence of the CCM would reduce the need for ATP and thus the need for electron transport to O2. Using mutants and inhibitors, we studied the involvement of known O2-dependent electron sinks such as the mitochondrial cytochrome and alternative oxidase pathways and also of chlororespiration in this light-dependent O2 uptake and we found no evidence for the involvement of any of these processes. The alternative electron transport was even higher in a mitochondrial mutant devoid of complexes I and III and we suggest that this alternative electron transport could compensate for the absence of mitochondrial ATP synthesis in this mutant. By elimination, our results suggest that the alternative electron transport to O2 evidenced here could be driven by a Mehler-type reaction although we did not find direct evidences for increased Mehler-type activity in low CO2 cells. Additionally from fluorescence measurements performed directly in the cultures, we concluded that low CO2 cells had a lowest PSII photosynthetic efficiency and developed strong qE NPQ. Our results indicate that Chlamydomonas reinhardtii is capable to induce an ample thermal dissipation of excitation energy and the extent of this process is influenced essentially by the CO2 availability. In contrast with results obtained in previous studies, low temperature fluorescence spectra showed that in high light, high CO2 cells were characterised by a higher proportion of light energy absorbed by PSI compared to low CO2 cells. This was accompanied by a decrease of PSII antenna size as shown by DCMU-FR measurements. These findings are discussed in relation with the conflicting theories concerning the role of state transitions in the regulation of the cyclic electron transport around PSI. Our results support the idea that CEF is regulated by the redox state of the chloroplast rather than by state transitions. Over the last decades, microalgae have been increasingly studied because of their potential applications in industry. Despite a growing interest in microalgae mass cultures, the majority of studies on microalgae have been carried out at a laboratory scale and only few studies have addressed the question of photosynthetic adaptations in mass cultures. It is well known that CO2 addition increases the growth rate of microalgae and for this reason, some mass microalgae cultures are CO2 supplemented. Among the studies on microalgae mass culture, as far as we know, none directly compared high CO2 (CO2 supplemented air) and low CO2 (air) conditions. In the last part of our work, two outdoor open thin-layer cascade systems operated as batch cultures with the alga Scenedesmus obliquus were used to compare the productivity and photosynthetic adaptations in control and CO2 supplemented cultures in relation with the outdoor light irradiance. We found that the culture productivity was limited by CO2 availability beyond a threshold of daily irradiance. In the CO2 supplemented culture, we obtained a productivity of up to 25 g dw.m-2.day-1 and found a photosynthetic efficiency of 2.6%. Fluorescence and oxygen evolution measurements showed that ETR and oxygen evolution light saturation curves, as well as alternative electron transport were similar in algal samples from both cultures when the CO2 limitation was removed. In contrast, we found that CO2 limitation conducted to a decreased PSII photochemical efficiency and an increased light-induced heat-dissipation in the control culture compared to the CO2 supplemented culture. These features may contribute to the lower productivity observed in absence of CO2 supplementation in outdoor mass cultures of Scenedesmus obliquus. [less ▲]

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See detailSe "faire manger" par l'Autre. Stratégies féminines de définition de soi en contexte public.
Mescoli, Elsa ULg

Conference (2015, March 12)

Cette communication vise à étudier la participation des femmes migrantes marocaines à la vie sociale du « pays d’accueil » ; participation qui se réalise grâce aux activités de la vie quotidienne. En ... [more ▼]

Cette communication vise à étudier la participation des femmes migrantes marocaines à la vie sociale du « pays d’accueil » ; participation qui se réalise grâce aux activités de la vie quotidienne. En particulier, la performance publique des pratiques culinaires, observée dans une ville de la province de Milan, permet aux femmes considérées d’exercer une agency à l’intérieur des espaces institutionnellement concédés à l’expression des migrants. D’un côté, la consommation des « recettes de l’Autre » de la part de la population majoritaire détermine une incorporation de la diversité afin de la contrôler. De l’autre côté, la préparation de ces recettes consent aux migrantes d’exprimer leur subjectivité (individuelle et collective) de façon active et en présentant des aspects qui vont au-delà de la culture alimentaire. Une participation sociale fondée sur le partage de nourriture donne la possibilité aux femmes d’assumer un rôle actif dans la communauté locale, tout en affirmant ses propres spécificités. Des sujets tels que la liberté religieuse sont abordés, et certains droits peuvent être réclamés par des individus qui ont ainsi acquis une position politiquement importante au sein de la société locale. [less ▲]

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See detailFamilles de tâches en langues modernes : pistes de réflexion et propositions d'outils
Simons, Germain ULg; Pagnoul, Pierre ULg

Conference (2015, March 10)

Cette communication se focalise sur l'analyse du document "Familles de tâches en langues modernes", document "officiel" de la Communauté française de Belgique qui a introduit, entre autres, la notion de ... [more ▼]

Cette communication se focalise sur l'analyse du document "Familles de tâches en langues modernes", document "officiel" de la Communauté française de Belgique qui a introduit, entre autres, la notion de "types de productions langagières" et a influencé les outils d'évaluation proposés "à titre indicatif" aux enseignants pour les aider dans la conception de leurs épreuves certificatives. Dans cette communication, nous montrons aussi un exemple de tâche complexe ciblant le débat de société régulé et fournissons quelques outils d'observation et d'évaluation de cette tâche finale de communication. [less ▲]

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See detailHighly Luminescent Aqueous Ag2S Quantum Dots as New Generation Quantum Dots
Yağcı Acar, Havva Funda; Hocaoğlu, I.; Demir, F. et al

in Proceediing of the meeting (2015, March 09)

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See detailSubjectivations politiques et épreuve de soi. Le cas Sartre/Fanon
Cormann, Grégory ULg

Scientific conference (2015, March 05)

Detailed reference viewed: 9 (1 ULg)