References of "Poster"
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See detailStreptomyces from Moonmilk, an Untapped Source of New Bioactive Compounds
Martinet, Loïc ULg; Maciejewska, Marta; Adam, Delphine ULg et al

Poster (2017, May 24)

Moonmilk speleothems of limestone caves host a rich microbiome, among which Actinobacteria represent one of the most abundant phyla. Ancient medical texts reported that moonmilk had therapeutical ... [more ▼]

Moonmilk speleothems of limestone caves host a rich microbiome, among which Actinobacteria represent one of the most abundant phyla. Ancient medical texts reported that moonmilk had therapeutical properties, thereby suggesting that its filamentous endemic actinobacterial population might be a source of natural products useful in human treatment. In this work, a screening approach was undertaken in order to isolate cultivable Actinobacteria from moonmilk of the Grotte des Collemboles in Belgium, to evaluate their taxonomic profile, and to assess their potential in biosynthesis of antimicrobials. Phylogenetic analysis revealed that all 78 isolates were exclusively affiliated to the genus Streptomyces and clustered into 31 distinct phylotypes displaying various pigmentation patterns and morphological features. Phylotype representatives were tested for antibacterial and antifungal activities and their genomes were mined for secondary metabolite biosynthetic genes coding for non-ribosomal peptide synthetases (NRPSs), and polyketide synthases (PKS). The moonmilk Streptomyces collection was found to display strong inhibitory activities against a wide range of reference organisms, as 94, 71, and 94% of the isolates inhibited or impaired the growth of Gram-positive, Gram-negative bacteria, and fungi, respectively. Interestingly, 90% of the cave strains induced strong growth suppression against the multi-drug resistant Rasamsonia argillacea, a causative agent of invasive mycosis in cystic fibrosis and chronic granulomatous diseases. We are currently identifying molecules responsible for the observed antimicrobial activities which, next to few known bioactive compounds, also reveals many active compounds with molecular masses that do not correspond to known antibiotic deposited in web biomolecules databases such as KNapSAcK, Pubchem, Chemspider. The challenge is to increase the production yields of these unknown compounds, and purify them to further characterize their structure by NMR. Overall, our work supports the common belief that moonmilk might effectively treat various infectious diseases thanks to the presence of a highly diverse population of prolific antimicrobial producing Streptomyces, and thus may indeed constitute a promising reservoir of potentially novel active natural compounds. [less ▲]

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See detailAn anticancer molecule stemming from a plant root produced in a bioreactor
Vassaux, Antoine; Tarayre, Cédric ULg; Delvigne, Frank ULg et al

Poster (2017, May 24)

Secondary metabolites produced by plants or their symbionts have already shown specific properties: anticancer, anti-inflammatory, antibacterial, antifungal effects, etc. Astin C is a non-ribosomal ... [more ▼]

Secondary metabolites produced by plants or their symbionts have already shown specific properties: anticancer, anti-inflammatory, antibacterial, antifungal effects, etc. Astin C is a non-ribosomal peptide (secondary metabolite) produced by the fungus Villosirosea asteris, endosymbiont of the medicinal plant Aster tataricus, which has shown an interesting anticancer activity. The current challenge is the production of the molecule on a large scale and in higher quantities, either from the original fungus through fermentation technologies, or by a heterologous yeast strain having integrated the genes involved in the astin C biosynthesis pathway. The purpose of this workshop is to highlight the implementation possibilities of a strain producing a metabolite of interest. [less ▲]

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See detailTh17 cells impact on xenogeneic graft-versus-host disease
Delens, Loïc ULg; SERVAIS, Sophie ULg; Ehx, Grégory ULg et al

Poster (2017, May 24)

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See detailPrecision synthesis and characterization of novel functional polymers
Scholten, Philip ULg; Debuigne, Antoine ULg; Demarteau, Jérémy ULg et al

Poster (2017, May 23)

Among controlled radical polymerisation techniques, cobalt-mediated radical polymerisation (CMRP) has proven to be a valuable alternative in polymerising unreactive and unconjugated monomers of many ... [more ▼]

Among controlled radical polymerisation techniques, cobalt-mediated radical polymerisation (CMRP) has proven to be a valuable alternative in polymerising unreactive and unconjugated monomers of many different monomer classes under mild conditions, including α-olefins. In a reversible deactivation mechanism, a cobalt complex reversibly traps the active growing chains and converts them into dormant species, avoiding side reactions and allowing for a controlled polymerisation. A fine control over the architecture is possible and allows to synthesise a large diversity of unprecedented block and alternating copolymers. Furthermore, functionalisation of the α- and ω-chain ends is now also possible. In this poster, the polymerization of different vinyl monomers using CMRP has been investigated to design highly functional materials under mild experimental conditions. The copolymerisation behaviour of these novel monomers was examined, and the structure and thermal properties of the new copolymers were investigated. [less ▲]

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See detailStudy of VOCs in the interaction between Banana and Foc TR4
Berhal, Chadi ULg; De Clerck, Caroline ULg; LEVICEK, Carolina et al

Poster (2017, May 23)

Banana fruit (Musa sp.) ranks fourth in term of worldwide production, and has economical and nutritional key values. The popular and most dominant variety of the dessert banana group is the Cavendish ... [more ▼]

Banana fruit (Musa sp.) ranks fourth in term of worldwide production, and has economical and nutritional key values. The popular and most dominant variety of the dessert banana group is the Cavendish variety. Nowadays, the Cavendish is endangered by the newly emergent race of the Panama disease, caused by the fungal pathogen Fusarium oxysporum f.sp. cubense TR4 (Foc TR4). Despite the importance of the Volatile Organic Compounds (VOCs), which are secondary metabolites with a high vapour pressure, in their utility in the plant protection processes, they were never documented as a way to manage this disease on Cavendish. Thus, the aim of this PhD thesis is to study the VOCs in the specific interaction Cavendish/Foc TR4, as a way to manage this threat. Based on the work previously done with other plants at Gembloux Agro-Bio Tech/University of Liège/Belgium, a protocol was optimized for the extraction of the banana plant’s VOCs. And in parallel, models of in-vitro and in-vivo inoculations are under development, in order to distinguish the root zone from the upper part of the plant in the study. The results of the first analysis showed that the majority of the Cavendish VOCs belongs to the terpenes group, as well as ketones and an organic ester. The identified key VOCs of the interaction will be subject to toxicity tests, in order to determine their effect on the development of the plant and the pathogen. The banana plant is a staple food for more than 400 Million people in the world, while this disease persists as a major threat for its production, and this original study could contribute to the fight against this threatening disease. [less ▲]

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See detailDesign of polyphosphoester-based drug delivery systems by efficient thiol-ene reaction
Riva, Raphaël ULg; Vanslambrouck, Stéphanie; Ergül, Zeynep ULg et al

Poster (2017, May 23)

Thanks to their biocompatibility, biodegradability and their structure similar to natural biomacromolecules, polyphosphoesters (PPE) are appealing polymers for biomedical applications. In contrast to ... [more ▼]

Thanks to their biocompatibility, biodegradability and their structure similar to natural biomacromolecules, polyphosphoesters (PPE) are appealing polymers for biomedical applications. In contrast to polyesters, PPE properties and functionality are easily tuned via the chemical nature of the lateral chains. To enhance the drug loading capacity of PPE-based micelles used as carriers for the delivery of poorly soluble drugs, an efficient strategy to increase the lipophilicity of the PPE block of polyethylene oxide (PEO)-b-PPE amphiphilic copolymers has been investigated. A PEO-b-PPE copolymer bearing pendant vinyl groups along the PPE block was synthesized and then modified by thiol-ene click reaction with thiols bearing either a long linear alkyl chain (dodecyl) or a tocopherol moiety. Ketoconazole was used as model for hydrophobic drugs. Comparison of the loading contents and release profiles with PEO-b-PPE bearing shorter pendant groups is presented evidencing the key role of the structure of the pendant group on the PPE backbone. Finally, the low cytotoxicity of these novel PEO-b-PPE copolymers was also demonstrated. The tocopherol derivative was evidenced as particularly promising for drug delivery systems. [less ▲]

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See detailUsing crop modelling to determine the meteorological conditions to be implemented in an Ecotron facility - Prerequisites to improve the experimental design?
Dumont, Benjamin ULg; Leemans, Vincent ULg; Garré, Sarah ULg et al

Poster (2017, May 23)

An Ecotron is a facility where ecosystems are confined in experimental chambers, allowing the simultaneous control of environmental conditions and the on-line monitoring of processes. Under the threats of ... [more ▼]

An Ecotron is a facility where ecosystems are confined in experimental chambers, allowing the simultaneous control of environmental conditions and the on-line monitoring of processes. Under the threats of climate change and the pressure of a world growing population, such facilities will be of major importance to study the relations between climate change and agro-ecosystems.As it can quickly become time- and money-consuming, conducting experiments in an Ecotron will force researchers to cautiously select the climate of interest to be generated. They will thus need reliable tools to help them support the decision making process.Here, we present an innovative methodology, supported by the use of crop model, to assist researchers in finding the climatic conditions under which crop services will be impacted.The meteorological datasets among which the choice can be done were generated by the ALARO-0 model (RMI, Belgium) for current and future climatic conditions. Runs were conducted for the historical period 1981-2010, and for two time frames - 2041-70 and 2071-2100 - under two emissions scenarios - RCP 4.5 and 8.5.A crop model (STICS, INRA, FR) was run over the entire database. Crop model outputs were synthesized for the main crop phenological phases, i.e. the juvenile, vegetative and reproductive phases. A particular emphasis was put on agronomical outputs (biomass and grain yield) and crop growth stresses (deficit and excess of water, thermal and nutrient stresses).Using these outputs as selection criteria, a novel multi-criteria approach was designed to retro-select the specific climatic conditions allowing to reach certain outcomes (e.g. yield target) while simultaneously exhibiting given thresholds of stresses for any considered crop stages. [less ▲]

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See detailA surprising and dramatic neuroendocrine-immune phenotype of mice deficient in Growth Hormone-Releasing Hormone (GHRH)
Farhat, Khalil; Bodart, Gwennaëlle ULg; RENARD, Jeanne de Chantal ULg et al

Poster (2017, May 23)

In the framework of close interactions between the immune and neuroendocrine systems, Growth Hormone (GH) has been proposed to exert significant effects on the immune system, but there is not yet a ... [more ▼]

In the framework of close interactions between the immune and neuroendocrine systems, Growth Hormone (GH) has been proposed to exert significant effects on the immune system, but there is not yet a consensus about GH immunomodulatory properties. These studies investigated the immune and anti-infectious response of dwarf Ghrh-/- mice presenting a severe deficiency of the GHRH/GH/IGF-1 axis. In basal conditions, thymic parameters and T-cell responses of Ghrh-/- mice were not severely affected but a constant B-cell lymphopaenia was observed. Thus, we investigated vaccine and anti-infectious responses of Ghrh-/- mice toward Streptococcus pneumonia, a B-dependent pathogen, Ghrh-/- mice were unable to trigger production of specific IgM and IgG against serotype 1 pneumococcal polysaccharide (PPS) after vaccination with either native PPS (Pnx23) or protein-PPS conjugate (Prev-13) vaccines. These vaccines both include the serotype 1 (our S.pneumoniae strain) and provide an effective protection in mice. A short GH supplementation to Ghrh-/- mice (1 daily injection of 1 mg/kg GH for 4 weeks) restored IgM and IgG response to Pnx23 vaccine but not to Prev-13. This suggests that GH could exert distinct impacts upon spenic areas. Furthermore, after intranasal instillation of a non-lethal dose (defined by the full clearance by WT C57BL/6 mice after 24h) of serotype 1 S.pneumoniae, Ghrh-/- mice exhibited a dramatic susceptibility. This was proved by a marked time-dependent increase in pulmonary bacterial, a septicemia already 24h after infection and a survival limit of 72h. We also observed a dramatic decrease in lung B- and T-cell populations and an increase in proportion of inflammatory macrophages. By contrast, wild-type and heterozygote mice completely cleared S.pneumoniae infection after 24h. In conclusion, our data show without ambiguity that the somatotrope GHRH/GH/IGF-1 axis plays an important and unsuspected role in defense against S.Pneumoniae. [less ▲]

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See detailÉdition et étude de Gerard du Frattre, compilation épique du XVIe siècle
Lambert, Adélaïde ULg

Poster (2017, May 23)

Présentation du projet de thèse de doctorat.

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See detailUnprecendeted fluoroalkene-based copolymers through cobalt-mediated radical polymerization
Demarteau, Jérémy ULg; Ameduri, Bruno; Ladmiral, Vincent et al

Poster (2017, May 22)

The precision design of fluorinated copolymers is challenging but also attractive for future developments in a wide range of applications involving fluoropolymers, such as advanced coatings or ... [more ▼]

The precision design of fluorinated copolymers is challenging but also attractive for future developments in a wide range of applications involving fluoropolymers, such as advanced coatings or purification membranes. In particular, controlling the radical polymerization of fluoroalkenes remains extremely difficult because of the high reactivity of these monomers due to the lack of resonance stabilizing group on their double bond. Herein, Cobalt-Mediated Radical Polymerization (CMRP) was used to efficiently control the bulk copolymerization of perfluorohexylethylene (PFHE) and vinyl acetate (VAc). Well-defined statistical poly(PFHE-stat-VAc) copolymers with different compositions (0 < FPFHE < 0.5) were obtained accordingly. In some cases, fluorinated monomer content as high as 80 % by weight were achieved. Reactivity ratios were determined (rVAc = 0.18 and rPFHE = 0) and emphasized a clear tendency for alternation. Single step approach and sequential polymerization were assessed for the synthesis of novel PFHE/VAc block copolymers. Finally, the acidic hydrolysis of the pendant ester groups of these block copolymers led to the formation of novel highly amphiphilic macromolecules bearing a PVOH hydrophilic segment and a hydrophobic PFHE-based block. [less ▲]

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See detailSynthesis of cross-linked P(HEMA) particles in supercritical carbon dioxide for protein delivery
Parilti, Rahmet ULg; Howdle, Steven M.; Jérôme, Christine ULg

Poster (2017, May 22)

This project aims to develop a novel one-pot strategy to obtain well-defined cross-linked particles able to carry peptides/proteins in their core, as along with targeting and/or imaging agents on their ... [more ▼]

This project aims to develop a novel one-pot strategy to obtain well-defined cross-linked particles able to carry peptides/proteins in their core, as along with targeting and/or imaging agents on their surface. In addition to this objective, polymerisations will be carried out in supercritical carbon dioxide (scCO2), which confers environmentally benign features to the process. Here, we investigate the feasibility of free radical dispersion polymerizations of 2-hydroxyethyl methacrylate (HEMA) in scCO2. In order to ensure the successful dispersion in scCO2 novel diblock CO2-philic surfactants are employed. These diblock surfactants are formed from two different segments, a CO2-phobic block which has an affinity to the growing particles and a second CO2-philic block that ensures surfactant solubility. [less ▲]

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See detailLaccase detoxification of lignocellulose hydrolysate
Cornet, Iris; Soti, Valentin; Richel, Aurore ULg et al

Poster (2017, May 22)

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See detailFunctional emulsion-templated porous polymers by macromolecular surfactant anchoring strategies
Mathieu, Kevin ULg; Jérôme, Christine ULg; Debuigne, Antoine ULg

Poster (2017, May 22)

Macroporous polymer monoliths with interconnected structures have attracted considerable interest in the fields of supported catalysis, chromatography, water purification, etc. A popular and ... [more ▼]

Macroporous polymer monoliths with interconnected structures have attracted considerable interest in the fields of supported catalysis, chromatography, water purification, etc. A popular and straightforward synthesis approach for such open-cell polymers is based on the polymerization of high internal phase emulsion (HIPE). Advanced functional polyHIPEs were also produced via different post-modification strategies but the latter often consists in tedious multi-step processes. This communication aims at reporting an efficient one-pot macromolecular surfactant-assisted method for the simultaneous synthesis and chemical functionalization of macroporous polyHIPEs. Briefly, amphiphilic block copolymers prepared by nitroxide-mediated radical polymerization (NMP) or reversible addition-fragmentation chain transfer (RAFT) were used as HIPE stabilizers and grafted at the surface of the walls of polyHIPE during the polymerization process. The impact of the controlled radical polymerization mechanism on the porous structure, openness and functionalization of the monoliths will be discussed. This strategy was also implemented with alkyne-terminated copolymers in order to decorate the surface of the polyHIPE’s cavities with “clickable” moieties which broadens the scope of functional macroporous polymers. [less ▲]

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See detailProtein encapsulation into nanostructured CaCO3 microparticles templated by PEO-b-polyphosphoester using a supercritical CO2 process
Ergül, Zeynep ULg; Debuigne, Antoine ULg; Calvignac, Brice et al

Poster (2017, May 22)

The use of calcium carbonate microparticles is becoming more and more attractive in biomedical applications as proteins carriers for their controlled delivery in the body. We investigate the protein ... [more ▼]

The use of calcium carbonate microparticles is becoming more and more attractive in biomedical applications as proteins carriers for their controlled delivery in the body. We investigate the protein encapsulation by in situ precipitation of CaCO3 particles prepared by a process based on supercritical CO2 and using a new type of degradable well-defined double hydrophilic block copolymer composed of poly(ethylene oxide) and polyphosphoester block with an affinity for calcium like poly(phosphotriester)s bearing pendent carboxylic acids on each repeating monomer unit which evidenced an efficient structure for templating the formation of CaCO3 leading to unprecedented small-sized particles. Lysozyme was chosen as a model for therapeutic protein for its availability and ease of detection. It was found that by this green process, loading into the CaCO3 microparticles with a diameter about 2 μm can be obtained as determined by scanning electron microscopy. A protein loading up to 6.5% active lysozyme was measured by a specific bioassay (Micrococcus lysodeikticus). By encapsulating fluorescent-labelled lysozyme (lysozyme-FITC), the confocal microscopy images confirmed its encapsulation and suggested a core–shell distribution of lysozyme into CaCO3. [less ▲]

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See detailPERFORMANCES D’UNE MINI POMPE À CHALEUR RÉVERSIBLE FONCTIONNANT SUR L’AIR EXTRAIT : ÉTUDE NUMERIQUE ET EXPERIMENTALE
Ransy, Frédéric ULg; Gendebien, Samuel ULg; Lemort, Vincent ULg

Poster (2017, May 22)

La majeure partie de la consommation d’énergie des immeubles à appartement dits « basse énergie » est liée à la production d’eau chaude sanitaire et aux pertes par ventilation. De plus, ces immeubles sont ... [more ▼]

La majeure partie de la consommation d’énergie des immeubles à appartement dits « basse énergie » est liée à la production d’eau chaude sanitaire et aux pertes par ventilation. De plus, ces immeubles sont soumis à un risque de surchauffe non négligeable en été. Afin de minimiser leur consommation d’énergie, les systèmes HVAC utilisés dans ces bâtiments se doivent d’être performants et multitâches. Dans cette optique, l’Université de Liège teste actuellement une mini-pompe à chaleur réversible sur air extrait. Cet article présente les résultats expérimentaux obtenus en laboratoire et démontre quelles sont les variables qui influencent les performances de cette machine. Un modèle polynomial est également proposé. [less ▲]

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See detailL’impact de la réserve cognitive sur le fonctionnement exécutif au cours du vieillissement normal
Lesoinne, Alexia ULg; Simon, Jessica ULg; Gilsoul, Jessica ULg et al

Poster (2017, May 20)

Il existe une forte variabilité interindividuelle quant aux effets du vieillissement sur la cognition. Selon Stern (2009), les individus qui ont développé un haut niveau de réserve cognitive résisteraient ... [more ▼]

Il existe une forte variabilité interindividuelle quant aux effets du vieillissement sur la cognition. Selon Stern (2009), les individus qui ont développé un haut niveau de réserve cognitive résisteraient mieux aux effets du vieillissement. Afin de déterminer les facteurs de réserve cognitive qui expliquent le déclin exécutif dans le vieillissement, nous avons recruté 165 participants âgés de 59 à 81 ans. Ils ont effectué sept tâches évaluant le fonctionnement exécutif : des épreuves d’inhibition (Stroop et Incompatibilité de la TAP), de flexibilité (Flexibilité de la TAP, épreuve d’alternance arithmétique « plus-moins ») et de mise à jour (subtest Lettre-Chiffre de la MEM III, mise à jour de consonnes et tâche de 2-back). De plus, les participants ont complété différents questionnaires évaluant quatre facteurs de réserve cognitive (niveau d’études, parcours professionnel, activité physique et activités de loisir). Nous avons réalisé des analyses de régression linaire hiérarchique. Après avoir contrôlé les facteurs démographiques, nous avons observé que la réalisation d’au moins une activité culturelle au cours de la vie impactait positivement les capacités d’inhibition, alors que la mise à jour était impactée négativement par un trop grand nombre de loisirs domestiques. Lorsqu’on considère les loisirs actuellement pratiqués, nous observons que la réalisation d’au moins un loisir social a un impact positif sur la flexibilité alors que deux activités à caractère social sont nécessaires pour avoir un impact positif sur la mise à jour. En conclusion, nous observons un effet mitigé et différencié de la réserve cognitive sur le déclin exécutif. [less ▲]

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See detailLa nature des intérêts spécifiques distingue les personnes avec et sans retard de langage.
Chiodo, Liliane ULg; Majerus, Steve ULg; Eusèbe, Sandrine et al

Poster (2017, May 20)

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See detailSchizophrénie et psychopathie : Analyse des difficultés d’objectivation diagnostique à partir de la PCL-R
Matteucci, Marie; Englebert, Jérôme ULg; De Page, Louis et al

Poster (2017, May 20)

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See detailLa modalité est importante quand on mène un jugement de reconnaissance basées sur la fluence, mais les patients atteints d’amnésie ne s’en soucient pas
Thonnard, Adeline; Geurten, Marie ULg; Willems, Sylvie ULg

Poster (2017, May 20)

La reconnaissance chez les patients amnésiques repose principalement sur le sentiment de familiarité. Plusieurs études indiquent que ce sentiment de familiarité pourrait reposer sur la facilité de ... [more ▼]

La reconnaissance chez les patients amnésiques repose principalement sur le sentiment de familiarité. Plusieurs études indiquent que ce sentiment de familiarité pourrait reposer sur la facilité de traitement. Cependant, si les patients amnésiques utilisent normalement cette heuristique métacognitive est une question qui n’a pas encore été explorée de manière approfondie. Dans la présente étude, nous avons utilisé le paradigme de l'illusion de Jacoby et Whitehouse (1989) avec 8 patients atteints de troubles graves de la mémoire et 16 participants sains et appariés. La facilité de traitement a été induite lors du test de reconnaissance en présentant brièvement une amorce qui correspondait au mot devant être évalué. Les résultats préliminaires de cette étude ont révélé que la facilité de traitement induite par l’amorce augmentait les réponses de reconnaissance lorsque la phase d'étude et la phase de test étaient dans la même modalité sensorielle, mais non lorsque l'étude et le test étaient dans des modalités différentes. Les sujets sont donc capables de moduler leur utilisation de la facilité de traitement en tant qu’indice de mémoire en fonction de la non-diagnosticité perçue de cet indice. Cependant, cet effet de modalité semble limité aux participants sains. Les patients amnésiques quant à eux ne semble pas moduler leur utilisation de l'heuristique de fluence. Dans l'ensemble, ces résultats suggèrent que la facilité de traitement peut être utilisée comme un indice pour la reconnaissance dans l'amnésie. Cependant, cette utilisation est sujette à des changements métacognitifs. [less ▲]

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See detailClinical pathway evaluation for left and sigmoid colectomy in abdominal surgery
Mattart, Laurine; Stevens, Marie; Magis, David ULg et al

Poster (2017, May 19)

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See detailExploration des processus de recollection et de familiarité chez des patients présentant une plainte mnésique : une étude longitudinale
Simon, Jessica ULg; Collette, Fabienne ULg; SALMON, Eric ULg et al

Poster (2017, May 19)

Recollection refers to recall of details about past events, and familiarity is a feeling of oldness. In this study, we tested how recollection and familiarity are affected in patients with memory ... [more ▼]

Recollection refers to recall of details about past events, and familiarity is a feeling of oldness. In this study, we tested how recollection and familiarity are affected in patients with memory complaints compared to normal aging. We recruited 23 healthy older participants, 9 patients with subjective memory impairment (SCI) and 23 patients with mild cognitive impairment (MCI). Participants performed one 2-alternative forced-choice and one Yes-No recognition memory task including pictures and words, followed by a short neuropsychological evaluation. Fifteen healthy participants and 23 patients (9 SCI and 14 MCI) took part in a neuropsychological follow-up after a mean delay of 21 months. At inclusion, MCI patients had poorer performance in recognition than the other groups, which did not differ. MCI patients had worse performance regarding familiarity and recollection indexes compared to healthy controls and SCI, who exhibit similar performance. There was no interaction between groups and format or material. During the follow-up evaluation, five MCI returned to a normal level of efficiency and were considered as SCI. Based on the French adaptation of the free and cued selective reminding test (RLRI-16), we calculated cognitive decline curves in our patients. We observed that recollection and familiarity indexes were explained by the decline curves calculated on the number of freely recalled items. So, recollection and familiarity were used less efficiently in MCI than SCI although both groups complained about their memory. [less ▲]

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See detailTraiter l’alexithymie en Hôpital de Jour Psychiatrique : Identification des modulateurs favorisant une meilleure prise en charge
Nasello, Julian ULg; Servais, Catherine; Close, Mireille et al

Poster (2017, May 19)

L’alexithymie (i.e., incapacité à exprimer ses émotions par des mots) serait-elle sensible aux traitements psychothérapeutiques dispensés en Hôpital de Jour (HPJ) ? Quelles en seraient les variables ... [more ▼]

L’alexithymie (i.e., incapacité à exprimer ses émotions par des mots) serait-elle sensible aux traitements psychothérapeutiques dispensés en Hôpital de Jour (HPJ) ? Quelles en seraient les variables prédictives ? Notre recherche a porté sur 73 participants sélectionnés en HPJ et présentant des troubles de l’humeur. En comparant les scores d’entrée et de sortie, des réductions significatives ont été observées sur tous les aspects d’alexithymie. De plus, certaines variables impactant significativement sur l’alexithymie ont été mises en avant : variables démographiques (i.e., genre ; âge ; durée de séjour) ; médication ; variables du MMPI-2 ; support social perçu (PSS). Il apparait que le PSS ainsi que cinq variables mesurées par le MMPI-2 (e.g., les pratiques antisociales ou les attitudes négatives face au traitement) tendaient à réduire ou augmenter les niveaux d’alexithymie. Dès lors, ces résultats tendent à favoriser une conception plus flexible des traits de personnalité, à mettre en évidence le rôle fondamental de la régulation exogène des émotions et à fournir aux thérapeutes les variables à prendre en considération pour optimiser la prise en charge de l’alexithymie. [less ▲]

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See detailAssociation entre régulation circadienne du cycle de veille-sommeil et performance de mémoire de travail chez les personnes âgées
Schmidt, Christina ULg; Reichert, Carolin Franziska; Maire, Micheline et al

Poster (2017, May 19)

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See detailVieillissement non pathologique des fonctions exécutives : influence du polymorphisme nucléotidique val108/158met du gène COMT
Gilsoul, Jessica ULg; Manard, Marine ULg; Collette, Fabienne ULg

Poster (2017, May 19)

Introduction. Selon la Théorie des États-Duaux, les homozygotes Val sur le gène COMT possèderaient de meilleures capacités de flexibilité tandis que les individus Met/Met favoriseraient les capacités de ... [more ▼]

Introduction. Selon la Théorie des États-Duaux, les homozygotes Val sur le gène COMT possèderaient de meilleures capacités de flexibilité tandis que les individus Met/Met favoriseraient les capacités de stabilité. Ces effets génotypiques seraient amplifiés dans le vieillissement car la diminution des ressources cérébrales augmente l’influence des différences génétiques sur la cognition. Notre but est d’investiguer l’influence du polymorphisme nucléotidique COMTVal108/158Met sur les fonctions exécutives dans le vieillissement normal. Méthode. Trois fonctions exécutives ont été évaluées grâce à différentes tâches chez des participants jeunes (N=55) et âgés (N=45) portant l’un des génotypes du gène COMT (Val/Val, Val/Met, et Met/Met). Nous avons réalisé des tests t entre les deux groupes ainsi qu’une ANOVA 6 (Groupe : Jeunes-Met/Met, Jeunes-Val/Met, Jeunes -Val/Val, Âgés-Met/Met, Âgés-Val/Met, et Âgés-Val/Val) X 3 (Fonctionnement exécutif : Inhibition, Flexibilité, et Mise à jour) à mesures répétées avec le Fonctionnement exécutif comme facteur intra-sujet (p < ,05). Résultats. Jeunes et âgés différaient significativement sur les trois fonctions exécutives. Au sein des groupes jeunes et âgés, aucune différence significative n’a pu être mise en évidence entre les groupes génotypiques. De façon intéressante, le groupe des Âgés-Val/Val avait de plus faibles performances que le groupe des Jeunes-Val/Val en inhibition. Discussion. Comme attendu, nous avons trouvé un effet de l’âge sur toutes les fonctions exécutives. La différence entre les Jeunes-Val/Val et les Âgés-Val/Val en inhibition soutient l’idée d’une diminution avec l’avancée en âge des performances lorsqu’une composante de stabilité est requise par la tâche chez des individus possédant un génotype moins favorable pour cette composante. [less ▲]

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See detailViolence psychologique dans les relations amoureuses – Quelle tolérance à la perpétration et à la victimisation ?
Courtain, Audrey ULg; Glowacz, Fabienne ULg

Poster (2017, May 19)

Les relations amoureuses des jeunes adultes peuvent être empreintes de diverses formes de violences (psychologique, physique ou sexuelle). La recherche considère généralement que la violence psychologique ... [more ▼]

Les relations amoureuses des jeunes adultes peuvent être empreintes de diverses formes de violences (psychologique, physique ou sexuelle). La recherche considère généralement que la violence psychologique est moins grave que les formes physique ou sexuelle. Or, elle ne peut pas être négligée. Notre objectif de faire un état des lieux des violences psychologiques que ces jeunes peuvent agir ou subir dans leurs relations amoureuses, et d’explorer dans quelle mesure ils ont des attitudes qui tolèrent (ou pas) ces violences. Méthodologie : Un questionnaire papier a été administré à un large échantillon composé d’étudiants (N>1000, 18-25 ans) en Belgique francophone. Ce questionnaire reprend deux outils : l’un traitant de la violence dans les relations amoureuses (« Conflict in Adolescent Dating Relationships Inventory », Wolfe et al., 2001) et l’autre traitant des attitudes relatives à ces violences («Attitudes Toward Dating Violence Scale », Price & Byers, 1999). Résultats : Après un descriptif des prévalences de violences psychologiques agies et subies, ainsi que des attitudes des participants, nous traiterons des liens entre les violences psychologiques et les attitudes afférentes, en termes de perpétration et de victimisation. Tout au long de nos analyses, les différences de genre seront considérées. Discussion : Ces résultats nous montrent comment les violences psychologiques et leurs attitudes afférentes sont liés, tant en termes de perpétration que de victimisation. S’inscrivant dans la continuité des recherches américaines, nos résultats encouragent l’élaboration de programmes de prévention et de sensibilisation auprès des jeunes adultes par un travail sur les attitudes. [less ▲]

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See detailRecognition memory is associated with hippocampal volume in aging population: new evidence from brain imaging study
Narbutas, Justinas ULg; Blanpain, Manon ULg; Van Egroo, Maxime ULg et al

Poster (2017, May 19)

Introduction. The hippocampus is crucial for episodic memory, especially for recollection and pattern separation (i.e., the ability to store similar episodes as distinct memory traces). Episodic memory ... [more ▼]

Introduction. The hippocampus is crucial for episodic memory, especially for recollection and pattern separation (i.e., the ability to store similar episodes as distinct memory traces). Episodic memory declines with aging and this has been associated with hippocampal dysfunction. The main objective of our study was to explore how performance on a recognition memory task designed to assess pattern separation is associated with hippocampal volume in aging population. Method. Fourteen healthy late middle-aged participants (52-69 years-old) were evaluated on a Mnemonic Similarity Task (MST). In this task, participants study pictures and then have to discriminate between targets, similar lures, and unrelated foil objects. Recognition memory (RM) is assessed as the difference between hits and false alarms to unrelated foils, while pattern separation Bias metric (BPS) is the difference between the rate of ‘‘Similar’’ responses given to the lure items minus ‘‘Similar’’ responses given to the foils. Hippocampal volume was calculated using ASHS software, which uses T1-weighted and T2-weighted MRI to obtain optimal segmentation of hippocampal subfields. Results. Correlation analysis of preliminary data revealed that RM was significantly positively associated with the volume of the left subiculum and left perirhinal area 35. BPS was positively correlated with the volume of right CA2 region, but negatively associated with the volume of right CA3 region. Discussion. In a late middle-aged population, better visual recognition memory is associated with larger volume of the left subiculum and perirhinal area 35, two regions supporting representation of objects. [less ▲]

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See detailRecollection versus familiarité dans le vieillissement normal et pathologique : Impact du format du test
Simon, Jessica ULg; Gilsoul, Jessica ULg; SALMON, Eric ULg et al

Poster (2017, May 19)

If familiarity is better preserved than recollection in aging and in the early stage of Alzheimer's disease (Koen & Yonelinas, 2014), the experimental conditions promoting its use should be beneficial to ... [more ▼]

If familiarity is better preserved than recollection in aging and in the early stage of Alzheimer's disease (Koen & Yonelinas, 2014), the experimental conditions promoting its use should be beneficial to these populations. One condition influencing the relative contribution of recollection and familiarity during recognition is the format of the test. The aim of this study was to investigate the impact of test format on recollection and familiarity in normal aging and in MCI in two tasks where the level of performance is equalized. Seventy young participants, 70 younger-old (55-69 years old), 69 older-old (70-85 years old), and 13 MCIs were presented with forced-choice and yes/no visual recognition memory tasks with the Remember/Know/ Guess paradigm. Young participants had better recognition memory performance than younger-old, who performed better than older-old and MCIs. Recollection and familiarity declined progressively in healthy aging. In MCI, recollection was more affected than familiarity, but patients demonstrated a more liberal use of familiarity. Finally, test format did not influence strongly the results. Young people used recollection more often in the forced-choice task compared to the yes/no task. [less ▲]

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See detailLe fonctionnement exécutif dans le vieillissement normal : l’effet médiateur de la vitesse de traitement et du système attentionnel
Gilsoul, Jessica ULg; Simon, Jessica ULg; Collette, Fabienne ULg

Poster (2017, May 19)

Introduction. Le vieillissement normal est associé à une diminution d’efficacité des fonctions exécutives. Cependant, la source de ces difficultés pourrait résider dans certains facteurs « non exécutifs » ... [more ▼]

Introduction. Le vieillissement normal est associé à une diminution d’efficacité des fonctions exécutives. Cependant, la source de ces difficultés pourrait résider dans certains facteurs « non exécutifs ». Dès lors, cette étude a pour but de déterminer si la vitesse de traitement et les variables attentionnelles pourraient médier l’effet de l’âge sur le fonctionnement exécutif. Méthode. Des participants jeunes (N = 104) et âgés (N = 63) ont réalisé une batterie de 21 tâches exécutives (inhibition, flexibilité, mise à jour, et coordination de double tâches), attentionnelles (alerte phasique, attention sélective, et attention soutenue), et de vitesse de traitement. Des modèles de médiation avec la vitesse de traitement et le fonctionnement attentionnel pris séparément comme médiateurs ont été réalisés. Résultats. L’attention sélective médie significativement l’effet de l’âge sur la mise à jour [ΔR2 = 7%, p < ,001]. De plus, la vitesse de traitement médie significativement l’effet de l’âge sur la flexibilité [ΔR2 = 7%, p < ,001], la mise à jour [ΔR2 = 5%, p < ,001], et la coordination de double tâches [ΔR2 = 14%, p < ,001].Discussion. La médiation de l’effet de l’âge sur la plupart des fonctions exécutives par les mesures de vitesse est en accord avec la littérature montrant une grande influence d’un ralentissement de la vitesse de traitement sur la cognition. L’effet de l’âge sur l’inhibition ne semble médié par aucune des variables attentionnelles et de vitesse, ce qui est en accord avec l’hypothèse selon laquelle l’inhibition serait la première fonction cognitive à décliner avec l’avancée en âge (Zacks & Hasher,1988). [less ▲]

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See detailDes jeux de doigts pour renforcer les précurseurs des apprentissages scolaire
Dauvister, Estelle; Vossius, Line ULg; Rousselle, Laurence ULg

Poster (2017, May 19)

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See detailStructural and Magnetic Properties of Nanosized strontium Hexaferrite Powders: Experimental and theoretical investigation
Abraime, Brahim; Ait Tamerd, Mohamed; Mahmoud, Abdelfattah ULg et al

Poster (2017, May 18)

Strontium M-type hexagonal ferrites were synthesized at different calcination temperatures (800 °C, 1000°C and 1100 °C) using sol-gel autocombustion method. Thermogravimetric analysis (TGA), X-ray ... [more ▼]

Strontium M-type hexagonal ferrites were synthesized at different calcination temperatures (800 °C, 1000°C and 1100 °C) using sol-gel autocombustion method. Thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM), Mössbauer spectroscopy (MS) and superconducting quantum interference device magnetometer (SQUID) techniques were used to characterize crystal structure, phase composition, morphology and magnetic properties. TGA gives T=800 °C as beginning of suitable calcination. Hexaferrite structure of single phase is obtained according to XRD results for all samples with crystallite size between 28 nm and 35 nm. SEM images show the growth of grain size with increasing of annealing temperature. (BH)max is calculated based on SQUID results and shows an enhancement between T=800°C and T= 1000°C of 25%. The magnetic properties observed at low temperature are explained and confirmed by ab-initio calculations. [less ▲]

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See detailMécanismes de vieillissement des anodes à base de FeSn2 pour batteries Li-ion
Chamas, Mohamad; Mahmoud, Abdelfattah ULg; Tang, junlei et al

Poster (2017, May 18)

Les intermétalliques d’étain ont été proposés comme matériaux d’anode pour batteries Li-ion à forte densité d’énergie car leur capacité spécifique est bien supérieure à celle des anodes commerciales à ... [more ▼]

Les intermétalliques d’étain ont été proposés comme matériaux d’anode pour batteries Li-ion à forte densité d’énergie car leur capacité spécifique est bien supérieure à celle des anodes commerciales à base de carbone. Le mécanisme électrochimique est basé sur la transformation irréversible de FeSn2 en un composite formé de nanoparticules de fer et de Li3.5Sn lors de la première lithiation, puis de réactions réversibles modifiant la composition de Li3.5Sn, les particules de fer assurant la dispersion de ces particules à base d’étain [1]. Cependant, nous avons observé que l’électrode lithiée était instable dans le temps conduisant à l’autodécharge progressive de la batterie [2]. Ce phénomène de vieillissement a été caractérisé par spectrométrie Mössbauer du 57Fe et de 119Sn, par spectroscopie d’impédance et par mesures magnétiques (Figure 1). On montre que le composite Fe/Li3.5Sn se délithie progressivement au cours du temps conduisant à un composite faiblement lithié Fe/LixSn avec x<1. Les nanoparticules de fer sont stables et ne réagissent pas avec LixSn. Les atomes de lithium libérés réagissent avec l’électrolyte et modifient la morphologie de la couche SEI (Surface Electrolyte Interphase) située à la surface des particules LixSn du composite.[1] M. Chamas, M. T. Sougrati, C. Reibel, P.E. Lippens, Chem. Mater. 25, 2410 (2015). [2] M. Chamas, A. Mahmoud, J. Tang, S. Panero, M. T. Sougrati, P. E. Lippens, J. Phys Chem. C 121, 217 (2017). [less ▲]

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See detailModulation of NMDA receptor mediated excitatory synaptic currents in dopamine neurons of the substantia nigra
Destreel, Geoffrey ULg; Seutin, Vincent ULg; Engel, Dominique ULg

Poster (2017, May 17)

Dopamine (DA) neurons of the substantia nigra pars compacta (SNc) exhibit two main firing modes, spontaneous single action potential (AP) firing and bursting. The amount of DA released by these neurons in ... [more ▼]

Dopamine (DA) neurons of the substantia nigra pars compacta (SNc) exhibit two main firing modes, spontaneous single action potential (AP) firing and bursting. The amount of DA released by these neurons in target areas depends on the presynaptic AP firing pattern and is essential to modulate several aspects of behavior such as the control of movement. Bursting activity is mediated by excitatory afferents and specifically by the activation of NMDA receptors (NMDARs). However, the level of activation of NMDARs at these synapses during spontaneous synaptic activity is unknown. We assessed the occupancy of the glycine binding sites of the NMDAR by testing the effects of coagonists and by blocking the uptake of glycine on spontaneous excitatory postsynaptic currents (sEPSCs) in DA neurons of the SNc. Parasagittal midbrain slices (300 – 350 µm thickness) were cut from the brains 16- to 26- days old Wistar rats using a vibratome. Whole-cell recordings were made using warm (~35C°) standard artificial cerebrospinal fluid. sEPSCs were pharmacologically isolated and recorded at +40 and -70 mV. A large NMDAR-sEPSC component was present at +40 mV as revealed by the application of 50 µM D-AP5 (n=8, P < 0.001). At -70 mV, D-AP5 had no effect on the EPSC, as expected (n=7, P = 0.52). The mean amplitude of the average NMDAR sEPSC measured at +40 mV increased significantly from 8.6 ± 0.8 pA in control conditions to 10.9 ± 1.0 pA during bath application of 300 μM glycine (n=10, P < 0.001). We also investigated the effect of D-serine, the other coagonist at the NMDAR glycine site. The mean NMDAR EPSC amplitude measured at +40 mV showed a tendency toward larger values, from 6.8 ± 0.8 pA in control conditions to 8.8 ± 1.1 pA in the presence of 100 µM D-serine (n=4). Blockade of the glycine transporter-1 (GlyT1) significantly increased the mean amplitude of NMDAR sEPSCs measured at +40 mV from 7.1 ± 0.5 pA in control conditions to 10.5 ± 0.8 pA in the presence of 5 μM NFPS (n=8, P < 0.001). At -70 mV, NFPS had no effect on the AMPAR-sEPSC component, as expected (n=8, P = 0.23). In conclusion, our results indicate that the NMDAR glycine sites are not saturated by glycine and D-serine during sEPSCs in control conditions. [less ▲]

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See detailAharonov-Bohm oscillations of bosonic matter-wave beams in the presence of disorder and interaction
Chrétien, Renaud ULg; Dujardin, Julien; Petitjean, Cyril ULg et al

Poster (2017, May 17)

We study the one-dimensional (1D) transport properties of an ultracold gas of Bose-Einstein condensed atoms through Aharonov-Bohm (AB) rings. Our system consists of a Bose-Einstein condensate (BEC) that ... [more ▼]

We study the one-dimensional (1D) transport properties of an ultracold gas of Bose-Einstein condensed atoms through Aharonov-Bohm (AB) rings. Our system consists of a Bose-Einstein condensate (BEC) that is outcoupled from a magnetic trap into a 1D waveguide which is made of two semi-infinite leads that join a ring geometry exposed to a synthetic magnetic flux φ. We specifically investigate the effects both of a disorder potential and of a small atom-atom contact interaction strength on the AB oscillations. The main numerical tools that we use for this purpose are a mean-field Gross-Pitaevskii (GP) description and the truncated Wigner (tW) method. We find that a correlated disorder suppress the AB oscillations leaving thereby place to weaker amplitude, half period oscillations on transmission, namely the Aronov-Al’tshuler-Spivak (AAS) oscillations. The competition between disorder and interaction leads to a flip of the transmission at the AB flux φ = π. This flip could be a possible preliminary signature of an inversion of the coherent backscattering (CBS) peak. Our study paves the way to an analytical description of the inversion of that peak. [less ▲]

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See detailUse of a bio-based binder in the building sector
Gerbinet, Saïcha ULg; Briard, Vincent; Pigeolet, Jean-Pierre et al

Poster (2017, May 15)

A binder is a material or a substance that holds materials together, like a glue. In the building sector, binders have several applications: they can be used in producing wood panels such as MDF to paste ... [more ▼]

A binder is a material or a substance that holds materials together, like a glue. In the building sector, binders have several applications: they can be used in producing wood panels such as MDF to paste together the wood particles and give the panels their stabil-ity. They are also used in insulation materials, such as glass wool or stone wool to bind the fibers together. Traditional binders are mostly fossil-based (phenol-formaldehyde, urea-formaldehyde, etc.), and previous Life Cycle Assessments (LCA) [1-3] show that these binders, even if they are a minor component on a mass basis, can have a major contribution to the environmental impact of the material, especially in wood panels. In addition, the use of these binders has raised some sanitary questions, especially con-cerning indoor air quality. Therefore alternative binders are being investigated, namely bio-based binders. In this presentation, we focus on the ECOSE binder, developed by Knauf Insulation, a global building insulation manufacturer. It has the particularity of being based on plant starch and it is currently used in glass wool products, while other applications are being developed. We underline that using biomass as raw materials instead of fossil-based ma-terials could have several benefits on the environment, especially fossil resources deple-tion and CO2 emissions, but that this is not necessarily the case for all environmental as-pects, for instance land use, even if only the direct land use is included in this study. The presentation will first underline the differences in term of environmental impact be-tween the traditional binder and ECOSE applied in glass mineral wool. Indeed, a compar-ison on a mass basis is not totally relevant: two binders can have different application conditions; therefore, we can only compare them at the application level. But the main focus of the presentation will be on the hypothesis made in the modeling of the biomass part and their influence on the results. For example, the influence of the use of bio-based raw materials instead of traditional ones will be studied, but also the influence of the dis-tance between farm and factory where the starch is produced. The use of local data will be compared with the use of databases. All these results will highlight the difficulties in studying bio-based products and to compare them with fossil-based ones. The use of LCA and a complete analysis of the results are essential to better understand the chal-lenges related to binder technology modification. ________________________________________ 1. Rivela, B., et al., Life cycle inventory of particleboard: A case study in the wood sector. International Journal of Life Cycle Assessment, 2006. 11(2): p. 106-113. 2. Wilson, J.B., Particleboard: A Life-Cycle Inventory of Manufacturing Panels from Resource through Product, in CORRIM: Phase II Final Report. 2008, Department of Wood Science and Engineering, Oregon State University. 3. Silva, D.A.L., et al., Environmental performance assessment of the melamine-urea-formaldehy (MUF) resin manufacture: a case study in Brazil. Journal of Cleaner Production, 2015. 96. [less ▲]

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See detailBelgian speleothem records Holocene cold events?
Allan, Mohammed ULg; Deliège, Adrien ULg; Nicolay, Samuel ULg et al

Poster (2017, May 12)

Speleothem is now regarded as valuable archive of climatic conditions on the continents, offering a number of advantages relative to other continental climate proxy recorders such as lake sediments and ... [more ▼]

Speleothem is now regarded as valuable archive of climatic conditions on the continents, offering a number of advantages relative to other continental climate proxy recorders such as lake sediments and peat cores. High spatial resolution measurements of Mg, Al, Sr, Ba were realized by using laser-ablation inductively coupled plasma mass spectrometry in the Belgian Pere Noel cave. A stalagmite from the Pere Noel (PN) cave representing 12000 years dated by U/Th method. Trace element variations in speleothem are a reflection of hydrochemical conditions. These changes were interpreted as indications of changes in climate in the Han-sur-Lesse region. The similar patterns found in δ 18O, δ 13C and chemical composition along the Pere Noel stalagmite suggests that trace elements in speleothems have the potential to provide high resolution insights into palaeoclimatic variability during the Holocene. A deeper analysis reveals several periods of significant rapid climate change during the Holocene (at 10.7-9.2 ka, 8.2-7.9 ka, 7.2-6.2 ka, 4.8-4.5 ka, and 3-2.4 ka BP), which are similar to the cold events detected from different natural paleoclimate archivers. A comparison between the geochemical analysis of Père Noël speleothem and solar activity (sunspot number) reveals a significant correlation. Spectral analysis methods reveal common solar periodicities (Gleissberg cycle, de Vries cycle, unnamed 500 year, Eddy cycles, and Hallstatt cycle). The geochemical analyses have the potential to prove that PN speleothem is sensitive to changes in solar activity on centennial and millennial timescales during the Holocene. [less ▲]

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See detailToRQuEMaDA: Tool for retrieving queried eubacteria, metadata and dereplicating assemblie
Léonard, Raphaël ULg; Sirjacobs, Damien ULg; Sauvage, Eric ULg et al

Poster (2017, May 11)

The fast-growing number of available prokaryotic genomes, along with their uneven taxonomic distribution, is a problem when trying to assemble broadly sampled genome sets for phylogenomics and comparative ... [more ▼]

The fast-growing number of available prokaryotic genomes, along with their uneven taxonomic distribution, is a problem when trying to assemble broadly sampled genome sets for phylogenomics and comparative genomics. Indeed, most of the new genomes belong to the same subset of hyper-sampled phyla, such as Proteobacteria and Firmicutes, or even to single species, such as Escherichia coli (>3000 genomes as of March 2017), while the continuous flow of newly discovered phyla prompts for regular updates of in-house databases. This situation makes it difficult to maintain sets of representative genomes combining lesser known phyla, for which only few species are available, and sound subsets of highly abundant phyla. An automated method is required but none are publicly available. In this work, the kmer composition of DNA sequences, in conjunction with quality metrics for publicly available assemblies, was used to develop an automated approach for selecting a high-quality subset of representative genomes without redundancy by using our hybrid divide-and-conquer / greedy clustering method. [less ▲]

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See detailStudy of the regulation of the operon ftsW-psr-pbp5 in Enterococcus hirae
Raymackers, Alice ULg; Maréchal, Maxime; Verlaine, Olivier ULg et al

Poster (2017, May 11)

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See detailCrosstalk between VEGF and BMP9 pathway. Implications in HHT disease
Pollenus, Thomas ULg

Poster (2017, May 11)

Detailed reference viewed: 12 (2 ULg)
See detailMAGED2 function as cell cycle regulator after a genotoxic stress
Trussart, Charlotte ULg; Pirlot, Céline; Piette, Jacques ULg et al

Poster (2017, May 11)

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See detailInnovative silage additives to reduce proteolysis in the silo
Herremans, Sophie ULg; Decruyenaere, Virginie; Beckers, Yves ULg et al

Poster (2017, May 10)

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See detailSmart-shoes self-powered by walking
Colson, Gérald ULg; Laurent, Philippe ULg; Bellier, Pierre ULg et al

Poster (2017, May 10)

Nowadays, electronic devices are more and more compact and can be integrated in nearly every object. One of the remaining challenges is to provide smarter ways to power those electronic devices. Because ... [more ▼]

Nowadays, electronic devices are more and more compact and can be integrated in nearly every object. One of the remaining challenges is to provide smarter ways to power those electronic devices. Because of the small amount of energy needed by the latest ultra-low power systems, energy harvesting from the environment becomes a viable solution to power them. In this work, we present the integration of an electronic device and an electrodynamic energy harvester (EH) in a shoe. The electronic device measures the acceleration along one axis at a sampling rate of 30 Hz and sends the data every second using a wireless link. The data are then collected by a gateway and processed to count the number of steps, calculate the contact time and the flying time of the foot. To perform this function, the device requires an average power of 951 μW which is provided by the EH. [less ▲]

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See detailLacustrine clay mineral assemblages as a proxy for land-use and climate changes over the last 4 kyr: The Amik Lake
El Ouahabi, Meriam ULg; Hubert, Aurelia ULg; Allan, Mohammed ULg et al

Poster (2017, May 10)

Lake sediments are sensitive to landscape changes and most of these changes seem to be modulated by land-use (anthropogenic factors) coupled to palaeoenvironmental/palaeoclimatic changes. In its detrital ... [more ▼]

Lake sediments are sensitive to landscape changes and most of these changes seem to be modulated by land-use (anthropogenic factors) coupled to palaeoenvironmental/palaeoclimatic changes. In its detrital fraction, the lacustrine sediments record the history of soil erosion within its catchment via the inputs of clays and others detrital products. Within a Mediterranean context, the study investigates the upper sediments infilling the central part of the Amik basin in southern Turkey. This tectonic basin was occupied and exploited by modern human at least since 6000-7000 BC. We focus on the clay mineralogy (x-ray diffraction on oriented aggregates) and magnetic susceptibility measurements (Bartington) of the sedimentary record in the area over the last 4000 years, to assess environmental changes in relation with the different land uses and/or weathering during the successive Bronze, Iron, Roman, Islamic/Ottoman and Modern civilizations. The clay fraction of Amik Lake sediments comprises smectite, kaolinite, illite, chlorite and chlorite/smectite mixed layers that are the inherited clay phases. A relative change in abundance and crystallinity and chemistry of illite attests that environmental conditions evolved in the Amik Plain from the Bronze to Modern Age in relation with climates and/or land-use changes. The history of the Amik Lake reveals different soil erosion episode. The most intense erosion phase occurred during the Bronze/Iron Ages as indicated by the clay and magnetic susceptibility proxies. The Roman period was an exceptional period with soil erosion products arriving from the watershed, probably due the water channelization. A reduction of soil erosion occurred during the post Roman period until nowadays. Significant pedogenesis transformations are evidenced, especially during the Islamic/Ottoman periods suggesting intense chemical weathering conditions related to climate change. [less ▲]

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See detailGlucose production: influence of the datasets and of the long term emissions on LCA results
Gerbinet, Saïcha ULg; Belboom, Sandra ULg; Léonard, Angélique ULg

Poster (2017, May 08)

The aim of this study is to have a good understanding of the environmental impact of glucose production. Glucose is generally produced from corn or wheat. Since agricultural processes are known to be ... [more ▼]

The aim of this study is to have a good understanding of the environmental impact of glucose production. Glucose is generally produced from corn or wheat. Since agricultural processes are known to be difficult to evaluate by LCA, the results obtained with two different LCA databases, Gabi and EcoInvent, are compared in this work. The production of glucose from raw materials can be divided in two steps: the agricultural step allowing the cereal production, and the conversion step including the extraction of the starch from the plant and its hydrolysis into glucose. Preliminary results underline the high impact of the agricultural step, so a special attention has been paid to these data. Specific Belgian data collected by the Walloon Agricultural Research Centre (CRA-W) (2014) [1] have been used as primary data (yield, amount of fertilizers, etc.), either using EcoInvent or Gabi datasets background data to model fertilizers, diesel consumption, etc. A third model was built using only data available in Ecoinvent for corn and wheat cultures. For the conversion steps, literature data have been used along with some industrial data. Based on these multiple sources, it is possible to compare the LCA results for the production of 1 kg of glucose for three different cases. The results underlined that the differences between the two databases are smaller than the differences between specific data (Belgium data) or non-specific data (Ecoinvent) for the agricultural steps. Nevertheless, in some impact categories, the differences between the two databases remain high. The presentation will underline where these differences are coming from. This leads to also analyze the differences between background data such as energy generation or fertilizer production. Moreover, special attention has been put on the influence of long-term emissions, in the Ecoinvent database. As these emissions have a large influence in some impact categories, we have to clarify if we should include them or not in view of comparison with GaBi database. Moreover, the Ecoinvent model and the GaBi models have been realized in two different software (Simapro and GaBi, respectively), therefore, some checks have been performed to see if some differences can be induced by the software. In conclusion, this presentation will underline which is the sensibility of the results to parameters not controlled by the LCA practitioner, such as the datasets hypotheses, the software differences, etc. 1. Walloon Agricultural Research Centre (CRA-W), ALT4CER project. 2014. [less ▲]

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See detailMONitOring des flux de POLluants dans les Eaux Souterraines
Jamin, Pierre ULg; Dassargues, Alain ULg; Brouyère, Serge ULg

Poster (2017, May 05)

Contaminated aquifers management is currently based on the evaluation of pollutant concentration in the groundwater. This approach is necessary but totally insufficient to evaluate the risk posed by the ... [more ▼]

Contaminated aquifers management is currently based on the evaluation of pollutant concentration in the groundwater. This approach is necessary but totally insufficient to evaluate the risk posed by the contamination to potential receptors. Since the risk is due to the pollutant that are actually moving, and might reach a receptor, this concentration measurement should be combined to a measurement of the groundwater flow velocity (i.e. the driving force of contaminant migration in aquifers), to quantify the contaminant mass flux at which the receptor is exposed. We propose a new point dilution technique able to measure accurately the groundwater flux and to monitor continuously its changes with time. [less ▲]

Detailed reference viewed: 32 (5 ULg)
See detailDesign of new reprocessable shape-memory materials
Defize, Thomas ULg; Riva, Raphaël ULg; Thomassin, Jean-Michel ULg et al

Poster (2017, May 04)

Detailed reference viewed: 9 (2 ULg)
See detailHow to exploit bio- and CO2-based isocyanates-free polyurethanes for environmental and biomedical applications?
Gennen, Sandro ULg; Grignard, Bruno ULg; Alves, Margot et al

Poster (2017, May 04)

Polyurethane (PU) is one of the most important family of polymers that is largely used in coatings, foams, elastomers, sealants/adhesives in the building, automotive, household and biomedical sectors ... [more ▼]

Polyurethane (PU) is one of the most important family of polymers that is largely used in coatings, foams, elastomers, sealants/adhesives in the building, automotive, household and biomedical sectors. Classically, PU is produced by a step-growth polymerization between di- or polyols and di- or polyisocyanates. However, isocyanates are toxic and produced from even more toxic phosgene. To avoid the use of isocyanates, different synthetic alternatives for PUs have been developed. One of the most studied approaches relies on the step-growth polymerization between di- or polyamines and CO2-sourced di- or polycyclic carbonates, affording poly(β-hydroxyurethane)s (PHUs) that showed improved thermal, chemical and mechanical properties compared to conventional PUs. In this study, we would like to show how PHUs can be exploited to design (bio- and) CO2-based foams for thermal insulation as well as novel reinforced hydrogels for potential biomedical applications. First, we developed a highly efficient binary organocatalyst for the fast and selective synthesis of cyclic carbonates under very mild conditions from CO2 and various epoxides, including bio-based ones. Secondly, these cyclic carbonates were valorised as monomers for the preparation of foams and hydrogels based on PHUs. In this poster, we will describe the preparation and characterization of these PHU foams and hydrogels, and highlight their huge potential as thermal insulating materials (PHU foams) or as biomaterials for shock absorption properties (PHU hydrogels). [less ▲]

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See detailThiol-ene reaction: an efficient tool to design polyphosphoester-based drug delivery systems
Riva, Raphaël ULg; Vanslambrouck, Stéphanie; Ergül, Zeynep ULg et al

Poster (2017, May 04)

Thanks to their biocompatibility, biodegradability and their structure similar to natural biomacromolecules, polyphosphoesters (PPE) are appealing polymers for biomedical applications. In contrast to ... [more ▼]

Thanks to their biocompatibility, biodegradability and their structure similar to natural biomacromolecules, polyphosphoesters (PPE) are appealing polymers for biomedical applications. In contrast to polyesters, PPE properties and functionality are easily tuned via the chemical nature of the lateral chains. To enhance the drug loading capacity of PPE-based micelles used as carriers for the delivery of poorly soluble drugs, an efficient strategy to increase the lipophilicity of the PPE block of polyethylene oxide (PEO)-b-PPE amphiphilic copolymers has been investigated. A PEO-b-PPE copolymer bearing pendant vinyl groups along the PPE block was synthesized and then modified by thiol-ene click reaction with thiols bearing either a long linear alkyl chain (dodecyl) or a tocopherol moiety. Ketoconazole was used as model for hydrophobic drugs. Comparison of the loading contents and release profiles with PEO-b-PPE bearing shorter pendant groups is presented evidencing the key role of the structure of the pendant group on the PPE backbone. Finally, the low cytotoxicity of these novel PEO-b-PPE copolymers was also demonstrated. The tocopherol derivative was evidenced as particularly promising for drug delivery systems. [less ▲]

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See detailSynthesis of cross-linked poly(HEMA) microparticles in supercritical carbon dioxide for sustained delivery
Caprasse, Jérémie ULg; Parilti, Rahmet ULg; Riva, Raphaël ULg et al

Poster (2017, May 04)

Microgels are micro-sized polymer networks able to swell or shrink depending on the environment. They find applications in many fields such as for environmental purpose or especially in the biomedical ... [more ▼]

Microgels are micro-sized polymer networks able to swell or shrink depending on the environment. They find applications in many fields such as for environmental purpose or especially in the biomedical field for tissue engineering or controlled drug-delivery applications. Indeed, the use of microgels allows a controlled and sustained release of an encapsulated active ingredient (AI), avoiding Burst release. This work aims at reporting on the solvent-free synthesis of well-defined hydrogel microparticles according to a free radical dispersion polymerization of hydroxyethyl methacrylate (HEMA) in supercritical carbon dioxide (scCO2) which confers environmentally benign features to the process2. For that purpose, a dedicated polymer surfactant has been designed by RAFT polymerization, i.e. poly(ethylene oxide-b-heptadecafluorodecyl acrylate) diblock copolymer with a photocleavable group at the junction of both blocks and used as stabilizer for the HEMA dispersion polymerization in scCO2. The synthesis conditions (stabilizer concentration, temperature and CO2 pressure,…) adapted for the in situ encapsulation of an active ingredient have been studied. Then, the photocleavage of the fluorinated block of the polymer stabilizer allows the further swelling of the polyHEMA particles in water and the sustained release of the encapsulated active ingredient through the microgels. This eco-friendly process allowing the formation of well-defined hydrogel particles, showing a sustain release of their content is quite promising for a high scale microparticles production. Microgels are micro-sized polymer networks able to swell or shrink depending on the environment. They find applications in many fields such as for environmental purpose or especially in the biomedical field for tissue engineering or controlled drug-delivery applications. Indeed, the use of microgels allows a controlled and sustained release of an encapsulated active ingredient (AI), avoiding Burst release. [less ▲]

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See detailDesign of polyphosphoester coplymers as scaffolds for tissue engineering applications
Shah, Urmil ULg; Ergül, Zeynep ULg; Jérôme, Christine ULg

Poster (2017, May 04)

Polymers with repeating phosphoester linkages in the backbone are biodegradable and emerged as a promising class of novel biomaterials. In contrast to polyesters, the pentavalency of the phosphorus atom ... [more ▼]

Polymers with repeating phosphoester linkages in the backbone are biodegradable and emerged as a promising class of novel biomaterials. In contrast to polyesters, the pentavalency of the phosphorus atom offers a large diversity of structures and as a consequence a wide range of properties for these materials. This study aims at taking profit of this easy functionalization to synthesize a series of degradable polymers of precisely tailored properties especially elasticity, hydrophilicity and functionality. We aim at developing a set of degradable materials in which only elasticity is varied keeping unchanged other parameters such as hydrophilicity, which remains quite a challenge. For that purpose, we have synthesized by organocatalyzed ring-opening polymerization,random di- and terpolymers between various cyclic phosphoesters bearing a short side-chain (hydrophilic), a longer side-chain (hydrophobic) and an unsaturated side-chain (butenyl)able to cross-link under UV irradiation. Playing on the composition of these copolymers, the cross-linking density and the hydrophilicity can be tuned quite independently. In the future, these materials will be used as model scaffolds to study the growth and differentiation of stem cells. [less ▲]

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See detailSynthesis of hierarchical N-doped porous carbon structure/nanospheres Fe2O3 composites and its application in lithium-ion battery as lithium-ion anodes
Alkarmo, Walid ULg; Ouhib, Farid ULg; Aqil, Abdelhafid ULg et al

Poster (2017, May 04)

Nitrogen-doped porous carbons are of special interest, because their unique physical properties such as high surface area, multidimensional electron transport pathways and good mechanical strength, and ... [more ▼]

Nitrogen-doped porous carbons are of special interest, because their unique physical properties such as high surface area, multidimensional electron transport pathways and good mechanical strength, and are thus very important for applications in the fields of catalysis, environment techniques and energy generation and storage. Moreover, nitrogen-doping can be further amplified in a porous structure that bears a high surface area to increases their materials performance in electrochemical devices, such as double layer capacitors and lithium-ion batteries. In addition, nitrogen-doping can enhance the lithium insertion, between the nitrogen-doped carbon material and lithium. And it can create a large number of defects in the porous configuration and offer more active sites for lithium insertion. Toward this goal, a hierarchically structured macro- and mesoporous N-doped carbon with dispersed Fe2O3 nanoparticles (NDC@Fe2O3) is prepared by thermal treatment of a novel composite composed by PMMA particles decorated by graphene oxide (GO), PPy and iron salts. The NDC@Fe2O3 composite exhibited high surface area with a hierarchical pores structure. Integrated as a lithium ion battery anode, NDC@Fe2O3 exhibited high reversible capacity of 930 mA h/g over 200 cycles. The combination of Fe2O3 nanoparticles with nitrogen-doped porous carbons to form hybrid anode has been an efficient way to maintain the electronic integrity of the whole electrode since the carbon acts as a buffer layer to accommodate the volume variation and to provide multidimensional electron transport pathways during the charge/discharge process. [less ▲]

Detailed reference viewed: 82 (9 ULg)
See detailPhoto-crosslinkable hydrogel for guided periodontal tissue regeneration
Chichiricco, Pauline Marie ULg; Riva, Raphaël ULg; Thomassin, Jean-Michel ULg et al

Poster (2017, May 04)

Periodontitis is an inflammatory disease resulting from the presence of oral bacteria biofilm in periodontal tissue, which destroys the tooth-supporting attachment apparatus. Untreated inflammation can ... [more ▼]

Periodontitis is an inflammatory disease resulting from the presence of oral bacteria biofilm in periodontal tissue, which destroys the tooth-supporting attachment apparatus. Untreated inflammation can spread to the gum tissue and lead, ultimately, to the loosening of the supporting tooth bone, with the risk that the tooth eventually falls. Guided Tissue Regeneration is a technique based on the application of a barrier membrane designed to prevent colonization of the wound space by epithelial cells from soft tissues. Indeed, these cells, characterized by a faster migration and proliferation rate compared to bone and periodontal ligament cells, could interfere with the regeneration process. In previously work Struillou et al. demonstrated the benefit effect of silated hydroxypropylmethylcellulose (Si HMPC)-based hydrogel can act as an efficient physical barrier in periodontal defect. Typically, this material is able to form a 3D network through the condensation of silanoate groups at physiological pH. However, a decrease of gelation time is necessary to assure the stability in peripheral part of the wound. In this project, we developed an injectable photo-crosslinkable membrane based on methacrylated carboxymethyl chitosan (CMCs) and Si HPMC that can be applied as a viscous solution and cured in situ in presence of a photoinitiator system made of riboflavin and triethanolamine. A visible light lamp (λ 420-480 nm), already used in dentistry, was preferred over a UV lamp. The addition of methacrylated polymer increase the stability of the material and increase the mass loss, in order to improve the bioresorption of the membrane. The chemical grafting of methacrylated carboxymethyl chitosan was characterized by 1H NMR and Infrared Spectroscopy. The gel point of the solution was determined by rheology and remained compatible with a clinical application. Moreover, the biocompatibility of this biomaterials was tested using murine cells using two assay: Neutral Red assay and MTT Cell Proliferation Assay. The in vitro tests validate the chemical synthesis in a biological point of view. The irradiation on cells and the direct contact with hydrogel doesn’t have an impact on cells viability. The capability of this material to act as a physical barrier was also evaluated using human gingival fibroblast. The cells were isolated from human gum explant before being put in contact with the hydrogel. After four days of contact no cells invasion was observed in the hydrogel using confocal microscopy. These preliminary results are quite promising for the development of novel injectable systems for Guided Periodontal Regeneration. In the future work, in vivo assays will be performed in Periodontal defect in a canine model. [less ▲]

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See detailQuantifying coral colony morphology to assess their roles in ecosystem processes
Chen, Qi; Yang, Emma; Sturaro, Nicolas ULg et al

Poster (2017, May 04)

Colony morphology is among the best predictors of the scleractinian coral’s function in the reef ecosystem. However, morphological traits are categorical and to convert this information into a ... [more ▼]

Colony morphology is among the best predictors of the scleractinian coral’s function in the reef ecosystem. However, morphological traits are categorical and to convert this information into a quantitative value remains a real challenge to quantify the influence of this parameter on ecosystem processes. Recently, the ratio between colony mass and surface area (CMA) has been proposed to represent a suitable proxy of species morphologies and their growth. Hypothetically, CMA could be used to assess a broad range of biological, ecological, and evolutionary processes in coral reef ecosystem. Here, we propose to test CMA as a predictor of coral morphology and focus on the intraspecific variation of this parameter. We used historical coral collection from the Museum of Zoology (National Taiwan University) and our own specimens collected from contrasting environments to establish a database of coral models using a high-resolution David 3D scanner. From these models, we extracted surface area and volume of the coral colonies. Colony mass was measured on a Mark S Bel balance. CMA was compared for its power in predicting species morphology with other traits such as skeleton density. Eventually, we tested the use of CMA at an intraspecific level to detect plasticity in growth rate. Our 3D models are available online (http://www.dipintothereef.com/corals.html) and constitute a valuable resource for estimating the roles of corals in the ecosystem. [less ▲]

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See detailReinforced poly(hydroxyurethane) coatings and high performance adhesive
Panchireddy, Satyannarayana ULg; Grignard, Bruno ULg; Thomassin, Jean-Michel ULg et al

Poster (2017, May 04)

Polyurethane (PU) is one of the most widely used polymeric materials and largely valorised in coating applications as paints or as adhesives. Because toxicity issues of isocyanates and changes in the ... [more ▼]

Polyurethane (PU) is one of the most widely used polymeric materials and largely valorised in coating applications as paints or as adhesives. Because toxicity issues of isocyanates and changes in the environmental and REACH regulations, there is a need today to develop new greener and safer alternatives to produce PU. One of the most promising way relies on the synthesis of polyurethane by a non-isocyanate route (NIPU) by copolymerization between a bicyclic carbonate monomers and a diamine. This study reports on the synthesis of new sustainable NIPU coatings for Al anti-corrosion protection and for metal adhesion. In a first step, (bio- and) CO2-sourced cyclic carbonates will be synthesized by coupling of multifunctional epoxides with CO2 using a new efficient bicomponent organocatalyst. In a second step, various cyclic carbonates/amines formulations were developed and cured in presence of fillers to produce reinforced NIPUs thermosets which anti-corrosion and adhesive properties are evaluated and benchmarked with existing formulations. Some formulations present outstanding adhesions to various substrates. [less ▲]

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See detailAll poly(ionic) liquid-based block copolymers incorporating fluorinated and triethyleneglycol units: direct synthesis in water and investigation as single-ion conductive solids
Ouhib, Farid ULg; Cordella, Daniela; Aqil, Abdelhafid ULg et al

Poster (2017, May 04)

Poly(ionic liquid)s (PILs) have attracted a considerable attention as innovative single-ion solid polyelectrolytes (SPEs) in substitution to the more conventional electrolytes for a variety of ... [more ▼]

Poly(ionic liquid)s (PILs) have attracted a considerable attention as innovative single-ion solid polyelectrolytes (SPEs) in substitution to the more conventional electrolytes for a variety of electrochemical devices. Imidazolium-based PILs are amongst the most investigated, because they are easy to synthesize and some of them have shown a good combination between high ionic conductivity, wide chemical and electrochemical stability, and good mechanical properties. Herein, we report the precise synthesis, characterization, and use as single-ion SPE of a novel double PIL-based amphiphilic diblock copolymer (BCP), i.e. where all monomer units are of N-vinyl-imidazolium-type, with triethylene glycol pendant groups in the first block, and a statistical distribution of N-vinyl-3-ethyl- and N-vinyl-3-perfluorooctyl-imidazolium bromides in the second block. BCP synthesis is achieved directly in water by a one-pot process, following the principle of the cobalt-mediated radical polymerization-induced self-assembly (CMR-PISA). A subsequent anion exchange reaction substituting bis(trifluoromethylsulfonyl)imide (Tf2N-) for bromide (Br-) counter-anions leads to the targeted PIL BCPs with two different lengths of the first block. They demonstrate ionic conductivity σDC = 1-3 10-7 S cm-1, as determined by broadband dielectric spectroscopy at 30 °C (under anhydrous conditions), and form free standing films with mechanical properties suited for SPE applications with Young’s modulus of 3.8 MPa and elongation at break of 250 % as determined by stress/strain experiments. [less ▲]

Detailed reference viewed: 54 (2 ULg)
See detailSynthesis of well-defined polyvinylamine-containing copolymers via organometallic-mediated radical polymerization
Stiernet, Pierre ULg; Demarteau, Jérémy ULg; Jérôme, Christine ULg et al

Poster (2017, May 04)

Polyvinylamine (PVAm) is a useful polymer involved in a large range of applications including paper coating, surface engineering, membrane separation, etc. It is commonly produced via free radical ... [more ▼]

Polyvinylamine (PVAm) is a useful polymer involved in a large range of applications including paper coating, surface engineering, membrane separation, etc. It is commonly produced via free radical polymerization of N-vinylformamide (NVF) or N-vinylacetamide (NVA) followed by hydrolysis of the pendent amides of the resulting polymers. Due to the lack of stabilizing group on the double bond of N-vinylamides, the controlled radical polymerization of these monomers remained a challenge for a long time, preventing the preparation of well-defined PVAms. Recently, our group reported the controlled polymerization of NVA via reversible deactivation of the growing radical chains with cobalt complexes. Moreover, the use of well-defined PVAms as efficient carriers for gene transfection was demonstrated. This communication aims at reporting the synthesis of novel well-defined polyvinylamine-based copolymers. First, we explored the organometallic-mediated radical copolymerization of NVA and vinyl acetate. The optimized polymerization conditions and the comonomer reactivity ratios will be presented. Further conversion of the pendent amides and esters moieties into amino and hydroxy groups, respectively, was also considered for the preparation of unprecedented hydrophilic polyvinylamine-based copolymers. [less ▲]

Detailed reference viewed: 23 (1 ULg)
See detailSimple, cheap but highly efficient organo catalysts for the fixation of CO2 on propargylic alcohols
Ngassam Tounzoua, Charlene Gabriela ULg; Gilbert, Bernard ULg; Detrembleur, Christophe ULg et al

Poster (2017, May 04)

In the last years, many efforts have been devoted to the valorisation of CO2 as an abundant and renewable C1 building block for cyclic carbonate synthesis. Many synthetic routes have been proposed to ... [more ▼]

In the last years, many efforts have been devoted to the valorisation of CO2 as an abundant and renewable C1 building block for cyclic carbonate synthesis. Many synthetic routes have been proposed to convert CO2 into five or six-membered cyclic carbonates finding applications as green solvent, electrolytes for Li-ion batteries, intermediates for organic synthesis, monomers for the production of polycarbonates or isocyanate-free synthesis of poly(hydroxyrethane)s, etc. Although the 100% atom economy synthesis of 5-membered cyclic carbonates from CO2 and epoxides/oxetanes has been widely reported in the literature, the carboxylative coupling of CO2 with alkynols remains unexplored. Transition metal-based complexes, organic bases (guanidine, amidine, phosphine), N-heterocyclic carbenes or olefins, and K2CO3 have been proposed as catalysts. However they generally present sufficient activity at high pressure and/or temperature or require a high catalyst loading. Additionally some of them are toxic and/or sensitive to hydrolysis or oxidation. In this work, we designed novel, cheap, easily customizable and highly efficient organocatalysts for the synthesis of cyclic α-methylene carbonates from CO2 and alkynols. Kinetics of the CO2/alkynol coupling reaction were followed by Raman spectroscopy with organocatalysts of different structures, and the best candidate was identified. The main parameters that influenced the system reactivity and selectivity have been identified and will be presented in this poster. [less ▲]

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Peer Reviewed
See detailTrace elements and organochlorines in sperm whales stranded on the coast of Schleswig Holstein in 2016
Pinzone, Marianna ULg; Schnitzler, Joseph ULg; Thomé, Jean-Pierre ULg et al

Poster (2017, May 02)

Several strandings of sperm whales occurred in the North Sea during January and February 2016. Twelve animals were necropsied and sampled after their discovery on German coasts of Schleswig Holstein ... [more ▼]

Several strandings of sperm whales occurred in the North Sea during January and February 2016. Twelve animals were necropsied and sampled after their discovery on German coasts of Schleswig Holstein. Muscle, liver, kidney and blubber samples were taken from all specimens for toxicological analyses. The concentrations of lipophilic organic pollutants such as polychlorinated biphenyl (PCB) and pesticides such as DDT were determined in adipose tissue. Metals and trace elements such as cadmium, selenium and mercury were measured in the liver, kidney and muscle. Polychlorinated biphenyls (PCBs) and pesticides such as DDTs were determined in adipose tissue at levels of 0.9 and 1.3 mg.kg-1 lipid weight respectively. Cadmium, selenium and mercury were measured in the liver at respective concentrations of 57, 52 and 81 mg.kg-1 dry weight. The investigated 12 sperm whales stranded on the coasts of Schleswig Holstein in spring 2016 showed a lower contamination of organic pollutants than the 7 sperm whales stranded along the Belgian and Dutch coast in the winter of 1994/95. These animals were clearly larger and older than the ones that stranded in Schleswig-Holstein. So, lower contaminant burden may be due to shorter life span. It seems unlikely that contamination is the direct cause of the death of sperm whales. However, debilitating role of pollutants cannot be excluded, as strandings are often a multi factorial event. Further investigations on the contaminant patterns among the 30 sperm whales at different stranding sites may also give indications on the feeding strategy and linkage among the individuals. [less ▲]

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See detailWal-e-Cities
Schelings, Clémentine ULg; Reiter, Sigrid ULg; Teller, Jacques ULg et al

Poster (2017, May 02)

L’objectif du portefeuille FEDER Wal-e-Cities est le développement de villes intelligentes («Smart Cities») au sein d’un territoire wallon interconnecté. La technologie, vue ici comme un outil au service ... [more ▼]

L’objectif du portefeuille FEDER Wal-e-Cities est le développement de villes intelligentes («Smart Cities») au sein d’un territoire wallon interconnecté. La technologie, vue ici comme un outil au service de la Smart Région Wallonne et de ses citoyens, permettra de répondre à cinq défis principaux identifiés: connectivité, mobilité, énergie et environnement, gouvernance et enfin bien-être en environnement urbain. Les partenaires de ce portefeuille (Universités et Centres de Recherche), et parmi eux l’UR Urban & Environmental Engineering de l'Ulg, oeuvreront au déploiement de solutions dédiées en regard des besoins spécifiques (géographiques, démographiques, socio-économiques et culturels) de chaque ville pilote partenaire. [less ▲]

Detailed reference viewed: 46 (7 ULg)
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See detailSAFIR: a software for modeling structures in fire
Franssen, Jean-Marc ULg; Gernay, Thomas ULg

Poster (2017, May 02)

SAFIR is a computer program developed at University of Liege to model the behavior of building structures subjected to fire.

Detailed reference viewed: 35 (2 ULg)
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See detailHybrid Fire Testing: A new approach for fire labs
Sauca, Ana ULg; Gernay, Thomas ULg; Mergny, Elke ULg et al

Poster (2017, May 02)

Detailed reference viewed: 22 (4 ULg)
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See detailEcomorphology of the axial skeleton in Odontocetes and Mysticetes
Gillet, Amandine ULg; Parmentier, Eric ULg

Poster (2017, May)

Ecomorphology concerns the study of the relationships between functional design and the environmental constraints acting on organisms. It aims to understand how the morphological variations among species ... [more ▼]

Ecomorphology concerns the study of the relationships between functional design and the environmental constraints acting on organisms. It aims to understand how the morphological variations among species can be related to environmental factors and impact fitness. Having a large diversity both in their morphology and ecology, the cetacean taxa appears to be the ideal taxa to tackle the relationships between the locomotor system and way of life. Different studies have already showed that the number and shape of vertebrae in different cetaceans can reflect the stiffness of the body and consequently can impact their swimming mode. The aim of this study is to establish relationships between characteristics of the vertebral column of different cetaceans and their ecology. Meristic and morphometric data were collected on the vertebrae (centrum lengths, heights and widths, neural spine heights and transverse processes lengths) of species of odontocetes housed in different Natural History Museums in the world (AM-ULg, RBINS, MNHN, SMNS, NRM, Queensland, PEM, Iziko). Preliminary results show clear morphological variations between species at the level of the number and sizes of vertebrae. There is a clear relationship between body size and number of vertebrae except in Delphinidae. This family has an important higher vertebral count. These differences should be related to different swimming modes and reflect the different ecological behaviours of the studied cetaceans. [less ▲]

Detailed reference viewed: 35 (7 ULg)
Peer Reviewed
See detailInvestigation of the glycolytic switch induced by saturated fatty acid in human macrophages
Colonval, Megan ULg; Fettweis, Grégory; L'homme, Laurent et al

Poster (2017, May)

Detailed reference viewed: 15 (2 ULg)
Peer Reviewed
See detailL’hospitalisation sous contrainte : Urgences psychiatriques et mises en observation.
Schmits, Emilie ULg; Evrard, Maude; Valassopoulou, Eftychia et al

Poster (2017, May)

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See detailSniffing Out the Hypoxia Volatile Metabolic Signature of Aspergillus fumigatus
Stefanuto, Pierre-Hugues ULg; Rees, Christiaan A.; Beattie, Sarah R. et al

Poster (2017, May)

Background: Aspergillus fumigatus is responsible for the life-threatening infection invasive aspergillosis (IA) that is associated with high mortality in immunocompromised individuals. Current diagnostics ... [more ▼]

Background: Aspergillus fumigatus is responsible for the life-threatening infection invasive aspergillosis (IA) that is associated with high mortality in immunocompromised individuals. Current diagnostics for IA are either highly invasive or suffer from inadequate sensitivity and/or specificity. Improvement of IA diagnostic assays requires a better understanding of fungal metabolism inside the host. The infection microenvironment becomes progressively depleted of oxygen during IA. Thus, metabolites associated with hypoxia metabolism may yield to novel diagnostic biomarkers. Here, we report on the volatile metabolites emitted from A. fumigatus batch cultures under normoxia and hypoxia conditions. Methods: A. fumigatus strain CEA10 was incubated in glucose minimal medium at 37 °C under either normoxia (21% O2, 0.04% CO2) or hypoxia (0.2% O2, 5% CO2) growth conditions. Volatile molecules from the supernatants of early (1 h) and late (8 h) cultures were collected using headspace solid-phase microextraction (HS-SPME) and analyzed using two-dimensional gas chromatography-time-of-flight mass spectrometry (GCxGC-TOFMS). Results: We identified 10 volatile compounds that are significantly more abundant in late hypoxia cultures compared with all other experimental conditions. Among these compounds, we identified ethanol and acetaldehyde, which are known to result from hypoxia metabolism of glucose by A. fumigatus. In addition, we detected 2-propanol, which can be generated by the reduction of acetone via alcohol dehydrogenase, as well as 2,3-butanedione (diacetyl) and 3-hydroxy-2-butanone (acetoin), which results from the catabolism of acetolactate. Transcriptomic data collected from normoxia and hypoxia cultures validates our volatilomic findings through the identification of putative catabolic pathways that are upregulated during hypoxia growth. Diacetyl is known to be produced by bacteria as a pH-neutral fermentative byproduct to prevent lethal acidification, and we speculate that A. fumigatus may use the same pathway. Conclusion: The composition of A. fumigatus’ volatile metabolome changes according to the oxygen tension in the environment. We measured hypoxia-associated compounds, ethanol and acetaldehyde which have been previously identified as byproducts of hypoxia metabolism in this organism. 2-propanol, 2, 3-butanedione and 3-hydroxy-2-butanone represent novel metabolites that suggests the existence of other catabolic pathways activated in A. fumigatus under hypoxia growth conditions. [less ▲]

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See detailTranscriptome wide analysis of natural antisense transcripts shows potential role in breast cancer
Wenric, Stéphane ULg; El Guendi, Sonia; CABERG, Jean-Hubert ULg et al

Poster (2017, May)

Non-coding RNAs (ncRNA) represent at least 1/5 of the mammalian transcript amount, and about 90% of the genome length is actively transcribed. Many ncRNAs have been demonstrated to play a role in cancer ... [more ▼]

Non-coding RNAs (ncRNA) represent at least 1/5 of the mammalian transcript amount, and about 90% of the genome length is actively transcribed. Many ncRNAs have been demonstrated to play a role in cancer. Among them, natural antisense transcripts (NAT) are RNA sequences which are complementary and overlapping to those of protein-coding transcripts (PCT). NATs were punctually described as regulating gene expression, and are expected to act more frequently in cis than other ncRNAs that commonly function in trans. In this work, 22 breast cancers expressing estrogen receptors and their paired healthy tissues were analyzed by strand-specific RNA sequencing. To highlight the potential role of NATs in gene regulations occurring in breast cancer, three different gene extraction methods were used: differential expression analysis of NATs between tumor and healthy tissues, differential correlation analysis of paired NAT/PCT between tumor and healthy tissues, and NAT/PCT read count ratio variation between tumor and healthy tissues. Each of these methods yielded lists of NAT/PCT pairs that were demonstrated to be enriched in survival-associated genes on an independent cohort (TCGA). This work allows to highlight NAT lists that display a strong potential to affect the expression of genes involved in the breast cancer pathology. [less ▲]

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See detailPlasma effects on the atomic structure and X-ray lines of astrophysical interest in oxygen ions
Deprince, J.; Palmeri, P.; Quinet, Pascal ULg et al

Poster (2017, May)

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See detailIdentifying infectious agents from lung transplant patients using GC×GC-TOFMS
Stefanuto, Pierre-Hugues ULg; Rees, Christiaan A.; Romamno, Rosalba et al

Poster (2017, May)

During the first year post-surgery, bacterial and fungal infections are the main causes of death in lung transplant recipients. Contributing substantially to the high mortality rate (35%) is the lengthy ... [more ▼]

During the first year post-surgery, bacterial and fungal infections are the main causes of death in lung transplant recipients. Contributing substantially to the high mortality rate (35%) is the lengthy time-to-diagnosis, which includes both pathogen identification and antibiotic resistance profiling. A novel diagnostic strategy based on the detection of volatile compounds in breath seems a promising option to improve these patients’ outcomes. In order to demonstrate the feasibility of this approach, we characterized the volatile fraction of different clinical matrices (i.e., bronchoalveolar lavage (BAL) and blind bronchial aspirate (BBA)). Due to the complexity of the mixture and high dynamic range of the concentrations, we applied headspace solid phase microextraction (HS-SPME) combined with comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC×GC-TOFMS) to obtain a comprehensive overview of the sample headspace composition. Following the analytical step, we applied various univariate and multivariate statistical methods (e.g. random forest, principal component analysis, and hierarchical cluster analysis) in order to extract required information from the data. Based on the composition of the volatile fraction, we were able to differentiate between BAL and BBA with a classification accuracy of 88.4 %. Furthermore, we could correctly distinguish between individuals with active respiratory infections and those without infection with a 72.2 % classification accuracy. In some cases, it was also possible to differentiate between pathogens at the species level. These results are preliminary evidence to suggest the possibility of detecting infections in these patient without the use of time-consuming culture techniques. [less ▲]

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See detailNew identification of energy levels in the astatine atom, the rarest element on Earth
Quinet, Pascal ULg; Sicorello, G.

Poster (2017, May)

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See detailMCDHF calculations of isotope shifts in neutral antimony
Gamrath, S.; Palmeri, P.; Quinet, Pascal ULg et al

Poster (2017, May)

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See detailSalmonella thyphimirium early onset neonatal sepsis
Thirion, Sophie ULg; RIGO, Vincent ULg; Snyers, Diane ULg et al

Poster (2017, May)

Background: Early onset neonatal sepsis due to salmonella spp is rare in developed countries. Vertical and horizontal transmissions were described, including faecal contamination of the birth canal. After ... [more ▼]

Background: Early onset neonatal sepsis due to salmonella spp is rare in developed countries. Vertical and horizontal transmissions were described, including faecal contamination of the birth canal. After a short incubation period, newborns may remain asymptomatic or present with sepsis or meningitis. Mortality rate as high as 58% were reported. Case Presentation Summary: We report a case of transplacental Salmonella Typhimurium infection in a premature infant. A mother with a one day history of fever and diarrhoea spontaneously delivered a premature boy at 35 weeks of gestation. On day 3, the infant presented with symptoms suggesting necrotizing enterocolitis: apnea, respiratory distress, feeding intolerance, bloody diarrhea and fever. Feeding were suspended and intravenous antibiotic therapy (ampicillin, amikacine and metronidazole) initiated. Laboratory data showed an inflammatory syndrome with elevated C-reactive proteine (71 mg/l), leukocytopenia (7270/mm3) and severe lymphopenia (580/mm3). Enterocolitis stage 1 (Bell classification) was diagnosed based on clinical and radiological evaluation. Salmonella spp were grown from the baby’s blood and stools and from the mother’s stools; the National Reference Center identified a Salmonella Typhimurium. Cerebrospinal fluid culture remained sterile. Clinical and biological evolutions were rapidly favourable with 14-days of cefotaxim IV. Maternal history revealed consumption of raw meat 3 days before delivery.Learning Points/Discussion: Salmonella spp should be considered in the differential diagnosis of early onset sepsis, particularly when mother presents gastrointestinal symptoms. Food safety education is crucial. The consumption of raw or uncooked meat during pregnancy should be avoided regardless toxoplasmosis immunization status. To avoid outbreaks in the neonatal ward (as reported in the literature), rapid detection and prompt institution of isolation and clustering measures are important. [less ▲]

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See detailInfluence qualitative et quantitative du mode de séchage sur l'huile essentielle de Thymus fontanesii de l'Algérie
Sidali, Lamia; Brada, Moussa; Fauconnier, Marie-Laure ULg et al

Poster (2017, May)

Cette étude a pour but d`étudier l`influence du mode de séchage (à l’ombre et au soleil) sur le rendement et la composition chimique de l`huile essentielle de Thymus fontanesii de l`Algérie obtenue par ... [more ▼]

Cette étude a pour but d`étudier l`influence du mode de séchage (à l’ombre et au soleil) sur le rendement et la composition chimique de l`huile essentielle de Thymus fontanesii de l`Algérie obtenue par extraction assistée par induction électromagnétique. Les résultats ont montré que le séchage à l`ombre a donné un meilleur rendement de (1.12%) après une période de séchage de 10 jours jusqu`à la stabilisation de teneur en eau, alors que le séchage au soleil pendant 8 jours donne un rendement de (0.89%). La composition chimique de l`huile essentielle de Thymus fontanesii (TF) a été analysé par la chromatographie en phase gazeuse couplée à la spectrométrie de masse (GC/MS) et la chromatographie en phase gazeuse a ionisation de flamme (GC/FID). [less ▲]

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See detailA surprising and dramatic neuroendocrine-immune phenotype of mice deficient in Growth Hormone-Releasing Hormone (GHRH)
Farhat, Khalil ULg; Bodart, Gwennaëlle ULg; Renard, chantal et al

Poster (2017, May)

In the framework of close interactions between the immune and neuroendocrine systems, Growth Hormone (GH) has been proposed to exert significant effects on the immune system, but there is not yet a ... [more ▼]

In the framework of close interactions between the immune and neuroendocrine systems, Growth Hormone (GH) has been proposed to exert significant effects on the immune system, but there is not yet a consensus about GH immunomodulatory properties. These studies investigated the immune and anti-infectious response of dwarf Ghrh-/- mice presenting a severe deficiency of the GHRH/GH/IGF-1 axis. In basal conditions, thymic parameters and T-cell responses of Ghrh-/- mice were not severely affected but a constant B-cell lymphopaenia was observed. Thus, we investigated vaccine and anti-infectious responses of Ghrh-/- mice toward Streptococcus pneumonia, a B-dependent pathogen, Ghrh-/- mice were unable to trigger production of specific IgM and IgG against serotype 1 pneumococcal polysaccharide (PPS) after vaccination with either native PPS (Pnx23) or protein-PPS conjugate (Prev-13) vaccines. These vaccines both include the serotype 1 (our S.pneumoniae strain) and provide an effective protection in mice. A short GH supplementation to Ghrh-/- mice (1 daily injection of 1 mg/kg GH for 4 weeks) restored IgM and IgG response to Pnx23 vaccine but not to Prev-13. This suggests that GH could exert distinct impacts upon spenic areas. Furthermore, after intranasal instillation of a non-lethal dose (defined by the full clearance by WT C57BL/6 mice after 24h) of serotype 1 S.pneumoniae, Ghrh-/- mice exhibited a dramatic susceptibility. This was proved by a marked time-dependent increase in pulmonary bacterial, a septicemia already 24h after infection and a survival limit of 72h. We also observed a dramatic decrease in lung B- and T-cell populations and an increase in proportion of inflammatory macrophages. By contrast, wild-type and heterozygote mice completely cleared S.pneumoniae infection after 24h. In conclusion, our data show without ambiguity that the somatotrope GHRH/GH/IGF-1 axis plays an important and unsuspected role in defense against S.Pneumoniae. [less ▲]

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See detailDeciphering the role of dendritic sodium channels on action potential dynamics in substantia nigra dopaminergic neurons
Moubarak, Estelle; Engel, Dominique ULg; Dufour, Martial et al

Poster (2017, May)

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See detailIs Young Adolescents’ Self-Esteem Predicted by Peer Acceptance? A Gender Perspective
Gaudet, Olivier; Vollet, Justin; Véronneau, Marie-Hélène et al

Poster (2017, May)

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See detailBasic Helix loop Helix transcription factor twist1a and twist1b and their involvement in the skeletal development of zebrafish.
Zappia, Jérémie ULg; Windhausen, Thomas ULg; Renn, Jörg ULg et al

Poster (2017, May)

1. Objective The twist1a and twist1b genes code for transcription factors involved during embryogenesis in the craniofacial development. The human ortholog of twist1a and twist1b, TWIST1 has been shown to ... [more ▼]

1. Objective The twist1a and twist1b genes code for transcription factors involved during embryogenesis in the craniofacial development. The human ortholog of twist1a and twist1b, TWIST1 has been shown to be mutated in cases of the Saethre–Chotzen syndrome (SCS). However, the roles of these genes in skeletal development in zebrafish remain to be clarified. The aim of our research is to characterize the effects of the knock-down of twist1a and twist1b in the zebrafish. 2. Methods Antisens morpholino are used for the knock-down of twist1a and twist1b (respectively MoTwist1a and MoTwist1b). The sox9a expression is investigated using whole amount in situ hybridization. 3. Results We show the spatio-temporal expression pattern of twist1a and twist1b during the first 6 days of zebrafish development and present the effects observed on cartilage and bone formation upon knock-down of these genes in zebrafish larvae. The results reveal a decrease of the cranial cartilage and bone formation in both MoTwist1a and MoTwist1b. Interestingly, when MoTwist1a and MoTwist1b are co-injected, the cranial cartilage formation is strongly reduced, while ectopic cartilage formation appeared in the front of the head. We also show an increase in expression of sox9a, a master regulator of chondrogenesis, in morphants. 4. Summary and Conclusions Even though it was shown that twist1a and twist1b maintain a pool of osteoprogenitor-like cells, we show that a knock-down of these genes induces a decrease of skeletal formation. Our hypothesis is that the morphants run out of progenitor cells to assure correct bone and cartilage formation. In the future, we plan to generate twist1a mutants in order to further characterize the effect of this mutation. The twist1a mutant will eventually serve for a rescue study using human TWIST1 mRNA, wild-type or mutant in order to have a better understanding of the human disorder SCS. [less ▲]

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See detailL'enseignement-apprentissage du français dans le qualifiant : regards croisés
Scheepers, Caroline ULg; Outers, Pierre ULg; Werner, Anne-Catherine ULg

Poster (2017, April 29)

La présentation donne à voir les résultats partiels d'une recherche exploratoire qui a consisté à questionner les élèves et les professeurs de l'enseignement secondaire de transition et du qualifiant à ... [more ▼]

La présentation donne à voir les résultats partiels d'une recherche exploratoire qui a consisté à questionner les élèves et les professeurs de l'enseignement secondaire de transition et du qualifiant à propos de leurs représentations relatives à l'enseignement-apprentissage du français dans le qualifiant. Pour l'heure, nous disposons des réponses apportées par 30 enseignants et par 450 élèves. A terme, cinquante enseignants et 1000 élèves sont concernés. [less ▲]

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See detailN2O eddy covariance fluxes : from field measurements to flux analysis
Lognoul, Margaux ULg; Debacq, Alain ULg; Heinesch, Bernard ULg et al

Poster (2017, April 28)

N2O eddy covariance data were collected for a complete season of sugar beet crop (from first fertilization to harvest). Data treatment and preliminary results are presented.

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See detailThree-dimensional modelling of the hydrodynamics of the Southern Bight of the North Sea: first results
Ivanov, Evgeny ULg; Capet, Arthur ULg; Barth, Alexander ULg et al

Poster (2017, April 28)

In the frame of the Belgian research project FaCE-It (Functional biodiversity in a Changing sedimentary Environment: Implications for biogeochemistry and food webs in a managerial setting), the impact of ... [more ▼]

In the frame of the Belgian research project FaCE-It (Functional biodiversity in a Changing sedimentary Environment: Implications for biogeochemistry and food webs in a managerial setting), the impact of dredging activities andoffshorewindfarminstallationonthespatialdistributionofsedimentgrainsize,biodiversityandbiogeochemistry will be estimated in the Southern Bight of the North Sea (SBNS) with a focus on the Belgian Coastal Zone (BCZ). To reach this goal, the three-dimensional hydrodynamical model ROMS-COAWST is implemented in the SBNS in order to simulate the complex hydrodynamics and sediment transport. Two levels of nesting are used to reach a resolutionof250mintheBCZ.Themodelisforcedattheair-seainterfacebythe6-hourlyECMWFERA-interim atmospheric dataset and at the open boundaries by the coarse resolution model results available from CMEMS (Copernicus Marine Environment Monitoring Service), and also considers tides and 4 main rivers (Scheldt, Rhine with Maas, Thames and Seine). Two types of simulations have been performed: a 10-years climatological simulation and a simulation over 20032013toinvestigatetheinterannualdynamics.Themodelskillsareevaluatedbycomparingitsoutputstohistorical data (e.g. salinity, temperature and currents) from remote sensing and in-situ. The sediment transport module will then be implemented and its outputs compared to historical and newly collected (in the frame of FaCE-iT) observations on grain size distribution as well as with satellite Suspended Particulate Matter (SPM) images. This will allow assessing the impact of substrate modification due to offshore human activities at local and regional scales. [less ▲]

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See detailGrazing-induced BVOC fluxes from a managed grassland
Mozaffar, Ahsan ULg; Schoon, N.; Bachy, Aurélie ULg et al

Poster (2017, April 28)

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