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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 detailMéthodologies créatives de la recherche en sciences du jeu : le cas de Super Mario Maker
Delbouille, Julie ULg; Hurel, Pierre-Yves ULg

Conference (2017, May 19)

Cette communication revient sur les premiers résultats de démarches méthodologiques créatives mises en place au sein du Liège Game Lab. Tentant de faire la synthèse entre l'ancrage principalement ... [more ▼]

Cette communication revient sur les premiers résultats de démarches méthodologiques créatives mises en place au sein du Liège Game Lab. Tentant de faire la synthèse entre l'ancrage principalement théorique des recherches francophones en sciences du jeu et l'orientation pratique des sciences informatiques des game labs anglophones, cette méthodologie s’inspire également des expérimentations d’autres centres de recherches tels que l’Utrecht Game Lab. L’expérience créative qui sera l’objet de cette communication s’appuie sur le dispositif Super Mario Maker. Au cours d'ateliers d’analyse et de création exploitant ce jeu, nous avons formulé cette question de recherche : « Est-il possible d'envisager l'univers fictionnel de la franchise comme un langage ? Et si oui, quelles en sont les modalités ? ». Au-delà de la confrontation de cette problématique à un outil de création vidéoludique (et les résultats qui en ont découlé), cette expérience nous a également permis de démystifier notre objet d’étude, et d’engager une dynamique de recherche collective. [less ▲]

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See detailAller au spectacle
Brahy, Rachel ULg

Conference (2017, May 18)

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See detailRadiohead and Prog Rock
Delville, Michel ULg

Conference (2017, May 18)

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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 detailAn exceptional Proterozoic assemblage of organic-walled microfossils and its implications for the early evolution of Eukaryotes
Loron, Corentin ULg; Rainbird, Rob; Greenman, Wilder et al

Conference (2017, May 18)

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See detailL’influence normative de la Chine en Amérique centrale: quels enjeux stratégiques ?
Wintgens, Sophie ULg

Conference (2017, May 18)

La République populaire de Chine (Chine) est aujourd’hui devenue un partenaire commercial incontournable, un important pourvoyeur d’investissements directs étrangers et un grand fournisseur de prêts ... [more ▼]

La République populaire de Chine (Chine) est aujourd’hui devenue un partenaire commercial incontournable, un important pourvoyeur d’investissements directs étrangers et un grand fournisseur de prêts financiers pour un nombre croissant de pays d’Amérique du Sud. Cette tendance s’observe également de plus en plus en Amérique centrale. L’accroissement de ses échanges économiques et commerciaux avec le Costa Rica, membre du Système d’intégration centraméricain (SICA) et premier pays centraméricain à avoir signé un accord de libre-échange avec Pékin, va de pair avec l’imposition des normes économiques et politiques dont sa politique commerciale internationale est porteuse. Ce constat pose dès lors la question du défi stratégique que représente cette influence normative chinoise pour les normes exportées par l’UE en Amérique centrale. Afin de répondre à cette question, cette communication se propose d’analyser la portée normative de la politique commerciale de la Chine envers l’Amérique centrale, afin de voir si elle est porteuse d’un projet politico-économique régional comparable au modèle d’intégration et de gouvernance régionale déployé par l’Europe communautaire dans le sous-continent. [less ▲]

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See detailThe epistemic politics of TA institutionalization and international TA collaboration – a cosmopolitan perspective
Rosskamp, Benedikt ULg

Conference (2017, May 18)

When addressing the issue of further institutionalization of TA, two assumptions need to be empirically confronted and conceptually revisited. A first one considers the evolution of TA as a linear ... [more ▼]

When addressing the issue of further institutionalization of TA, two assumptions need to be empirically confronted and conceptually revisited. A first one considers the evolution of TA as a linear progression leading to new institutional creations in an increasing number of countries. Despite a series of calls for distributed, networked, multi-level and multi-actor TA capacities, the idea of creating more single, national, specialized and dedicated TA organizations remains dominant in TA discourse. A second assumption concerns the rationale of Technology Assessment and its performance in terms of “opening up” and “broadening out” (Ely et al. 2014) or “the reflexivity pathway” (Delvenne 2011), notably by resorting to participatory Technology Assessment. Results from case studies in Wallonia, Portugal and the Czech Republic require reconsidering the above-mentioned evolutionary assumptions for a more complex and paradoxical understanding of the future of TA. While the TA achievements in each case study are still uncertain to a high degree, we can sum up these respective TA developments under the banner of “evidence-based governance”. This particular understanding of knowledge and decision-making is coherent with a simultaneous observed shift away from the institutional deficit of TA (creating new institutions in newcomer countries) to a renewed strategy of resorbing a knowledge deficit (making TA knowledge available to a wider number of countries). This renewed approach to TA collaboration and capacity building increasingly gains traction both from a bottom-up perspective where actors try to organize themselves into a critical mass and in a top-down perspective of neoliberal and austerity policies. In such a constellation, positivistic science provides an evidence-base, which supposedly supports multi-level, multi-actor governance as it allows knowledge produced in one place to travel and serve a wide spectrum of actors and decision-making arenas. The consequences of this shift are crucially important to explore the re-makings and futures of Technology Assessment, as they put to the fore the issue of subsidiarity of both the production and the use of TA knowledge. Finally, we identify a shift from coexistence to a cosmopolitan mode of epistemic subsidiarity (Jasanoff 2013, 2014). The latter raises a series of new theoretical, practical and normative questions for the TA community. [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 detailThe earliest eukaryotes
Javaux, Emmanuelle ULg

Conference (2017, May 18)

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See detailDu définitif sur du provisoire...
Englebert, Jérôme ULg; Follet, Valérie

Conference (2017, May 18)

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See detailL'interpellation stigmatisante comme élément de construction identitaire: le cas "Django Unchained"
Wintgens, Caroline ULg

Conference (2017, May 17)

La polémique apparue autour du film Django Unchained de Quentin Tarantino (2012) permet d’approcher la question de la représentation du stigmate. Mon étude portant sur cette polémique et sur les arguments ... [more ▼]

La polémique apparue autour du film Django Unchained de Quentin Tarantino (2012) permet d’approcher la question de la représentation du stigmate. Mon étude portant sur cette polémique et sur les arguments y étant mobilisés a montré que c’est la représentation d’éléments issus de la culture afro-américaine, ayant participé à la construction d’une identité pour les individus porteurs d’un stigmate ethnique, qui est particulièrement mise en cause. La polémique devient dès lors le lieu d’une resignification des attributs liés au stigmate et d’une réaffirmation de la culture de résistance élaborée autour de celui-ci par ceux qui en sont porteurs. Le terme Nigger et sa présence excessive dans le film ont notamment été relevés par de nombreux internautes. C’est dans ce cadre que nous approcherons la question toujours centrale de l’interpellation stigmatisante, en tant qu’elle semble à la fois devenir le lieu d’une réaffirmation identitaire et permettre l’émergence d’une « réponse habilitante » (Butler, 2008). [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 detailNON-INVASIVE ANALYSIS OF POTENTIALLY DYSREGULATED MIRNAS IN ENDOMETRIOSIS
Munaut, Carine ULg; Emonard, Violaine; TIMMERMANS, Marie ULg et al

Conference (2017, May 17)

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See detailImplementation of SFC for the quality control of pharmaceuticals
Dispas, Amandine ULg; Andri, Bertyl ULg; Lebrun, Pierre ULg et al

Conference (2017, May 17)

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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 detailLe manuel de grammaire latine de Dosithée : quelle méthode d'apprentissge ?
Rochette, Bruno ULg

Conference (2017, May 15)

Contrairement aux autres manuels de grammaire latine destinés aux hellénophones, comme ceux de Charisius, Diomède et Priscien qui travaillent dans la pars Orientis pour des hellénophones, l’Ars grammatica ... [more ▼]

Contrairement aux autres manuels de grammaire latine destinés aux hellénophones, comme ceux de Charisius, Diomède et Priscien qui travaillent dans la pars Orientis pour des hellénophones, l’Ars grammatica de Dosithée est accompagnée d’une traduction grecque. La présence de cette traduction, qui ne concerne toutefois pas toute la grammaire, mais seulement environ la moitié du texte, singularise ce manuel dans la tradition des artes, même si nous ne pouvons exclure que d’autres traités grammaticaux du même type n’aient pas été accompagnés d’une traduction grecque que nous n’aurions pas conservée. Quoi qu’il en soit, le statut de cette traduction est assez difficile à établir. Essentiellement deux questions se posent à son sujet : quel est son auteur, est-ce Dosithée lui-même ou un utilisateur plus tardif (éventuellement dans le monde occidental), et à quoi sert-elle ? Il apparaît clairement que le grec doit aider à la compréhension du latin, non le remplacer. La traduction grecque n’a donc pas une vocation à l’autonomie. Elle n’a de sens qu’en relation avec le latin. La traduction semble se réduire au fur et à mesure que l’on avance dans la grammaire. Il semble que Dosithée attende de l’utilisateur de la grammaire qu’il ait de moins en moins besoin d’aide à mesure qu’il progresse dans l’apprentissage. J’analyse la nature du grec de Dosithée en vue de mieux comprendre la méthode d’apprentissage mise en œuvre dans ce manuel. Bibliographie Bonnet G., Dosithée. Grammaire latine, Paris, CUF, 2005. --, La version grecque de l’Ars de Dosithée, dans L. Basset-Fr. Biville-B. Colombat-P. Swiggers-A. Wouters (éds), Bilinguisme et terminologie grammaticale gréco-latine, Leuven-Paris-Dudley, 2007, p. 191-199. Dickey E., The Authorship of the Greek Version of Dositheus’ Grammar and What it Tells Us about the Grammar’s Original Use, dans R. Ferri-A. Zago (eds), The Latin of the Grammarians. Reflections about Language in the Roman World, Turnhout, 2016, p. 205-235. --, Learning Latin. The Ancient Way. Latin Textbooks from the Ancient World, Cambridge, 2016. Lenoble M. – Swiggers P. – Wouters P., L’enseignement grammatical entre grec et latin : le manuel de Dosithée, P. Desmet-L. Jooken-P. Schmitter-P. Swiggers (eds), The History of Linguistic and Grammatical Praxis. Proceedings of the XIth International Colloquium of the Studienkreis « Geschichte der Sprachwissenschaft » (Leuven, 2nd – 4th July, 1998), Leuven-Paris-Sterling, 2000, p. 3-22. Reichamnn V., Römische Literatur in griechischer Übersetzung, Leipzig, 1943. J. Tolkiehn J., Dosithei Ars Grammatica, Leipzig, 1913. [less ▲]

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See detailLa maladie du Renard Wallon!
DETRY, Olivier ULg

Conference (2017, May 13)

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See detailA New Perspective on Mary of Hungary’s Labours of Hercules Tapestries (Patrimonio Nacional, series 23)
Laruelle, Anne-Sophie ULg

Conference (2017, May 13)

This lecture aims to shed new light on the twelve-piece set purchased in 1535 by the governess of the Netherlands, Mary of Hungary, from the Dermoyen workshop in Brussels. It focuses on four main themes ... [more ▼]

This lecture aims to shed new light on the twelve-piece set purchased in 1535 by the governess of the Netherlands, Mary of Hungary, from the Dermoyen workshop in Brussels. It focuses on four main themes: the existing pieces and their iconography, the manufacture that woven them, the artists who provided the models to the weavers and finally the patron who chose the subject and gave these tapestries a precise function in her interior. [less ▲]

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See detailHow to count leaves in the trees from Tetris?
Vandomme, Elise ULg

Conference (2017, May 13)

In the world derived from the game Tetris, what is a tree? How many leaves can such a tree can have? What happens if instead, we consider the world derived from the game Minecraft? Can we generalise this ... [more ▼]

In the world derived from the game Tetris, what is a tree? How many leaves can such a tree can have? What happens if instead, we consider the world derived from the game Minecraft? Can we generalise this problem in other worlds? Does there exist an efficient algorithm to determine the maximal number of leaves a tree can have? These are the questions we will answer in this talk, using the point of view of graph theory. To determine the complexity of the problem, we will use some dynamical programming. [less ▲]

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See detailAux frontières du réel : de l’immersion aux formes de jeu « secondaire »
Delbouille, Julie ULg; Hurel, Pierre-Yves ULg; Barnabé, Fanny ULg et al

Conference (2017, May 12)

Dans les sciences du jeu, la problématique du franchissement de la frontière qui nous sépare des mondes virtuels se cristallise particulièrement à travers le concept d’immersion. S’il est constamment ... [more ▼]

Dans les sciences du jeu, la problématique du franchissement de la frontière qui nous sépare des mondes virtuels se cristallise particulièrement à travers le concept d’immersion. S’il est constamment employé pour étudier le rapport que le joueur entretient avec le jeu, il reste cependant peu problématisé ; plus encore, son omniprésence et l’hétérogénéité (parfois contradictoire) de ses définitions empêche de penser l’acte de joueur en dehors du prisme de ce paradigme. Cette communication vise, d’une part, à souligner les limites et les écueils de l’emploi de ce concept au sein des game studies et, d’autre part, à mettre en lumière des pratiques que l’immersion a, jusqu’à présent, contribué à reléguer au second plan de la recherche. [less ▲]

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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

Conference (2017, May 12)

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 detailTime perspective and emotional future-oriented thoughts
Barsics, Catherine ULg

Conference (2017, May 12)

Time perspective —the tendency to focus on the past, present, and/or future— has a pervasive influence on many aspects of human cognition and behaviour, such as decision making, planning, motivation, self ... [more ▼]

Time perspective —the tendency to focus on the past, present, and/or future— has a pervasive influence on many aspects of human cognition and behaviour, such as decision making, planning, motivation, self-regulation, and sense of identity. Over the last decade, important progress has been made in understanding the representations and processes that support our ability to mentally explore possible futures. More particularly, many thoughts and mental images that people form about their personal future refer to emotionally significant events. Such emotional future-oriented thoughts (EmoFTs) were studied in natural settings and under laboratory conditions. The results showed that EmoFTs are frequent, occur in various contexts, and are perceived to fulfill important functions, mostly related to goal pursuit and emotion regulation. The phenomenological characteristics of EmoFTs (e.g., representational format) vary according to valence. When distinguishing between anticipatory and anticipated emotions (i.e., emotions experienced in the present versus emotions expected to occur in the future), a positivity bias in the frequency of EmoFTs is found to be restricted to anticipated emotions. These findings shed further light on the properties of future oriented-thoughts, and emphasize the importance of their affective components. [less ▲]

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See detailNGS for NBS : Are we ready for « Next Generation » Newborn Screening ?
BOEMER, François ULg

Conference (2017, May 12)

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See detailÀ la recherche d"une réalité "vraie" : entre peur métaphysique et angoisse dans l'autofiction (néo)fantastique hispano-américaine
Licata, Nicolas ULg

Conference (2017, May 12)

Après avoir déterminé les limites que lui concèdent des disciplines comme l’histoire des émotions, la psychanalyse et la philosophie, cette communication se centre sur la peur comme effet de la ... [more ▼]

Après avoir déterminé les limites que lui concèdent des disciplines comme l’histoire des émotions, la psychanalyse et la philosophie, cette communication se centre sur la peur comme effet de la littérature fantastique, et plus concrètement dans le cadre de cette catégorie spécifique de romans que Vincent Colonna a baptisé « autofiction fantastique ». À la lumière de trois de ces fictions fantastiques modernes articulées autour de leurs propres auteurs, nous expliquerons pourquoi, à notre avis, l’effet qu’elles produisent chez le lecteur diffère de la peur. Il ne s’agit pas d’un effet inférieur ni supérieur, mais simplement différent : l’angoisse. [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 detailCrosstalk between VEGF and BMP9 pathway. Implications in HHT disease
Pollenus, Thomas ULg

Poster (2017, May 11)

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See detailWelcome & Overview ChemEng Liège
Pfennig, Andreas ULg

Conference (2017, May 11)

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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 detailL'APL en région wallonne. Référence et contrôle : méthodologie et résultats
Vandenberghe, Christophe ULg

Conference (2017, May 11)

En région wallonne (Belgique), des contrôles sont chaque année organisés en vue de mesurer l'azote nitrique présent dans les parcelles d'agriculteurs situés en zone vulnérable. Les résultats de ces ... [more ▼]

En région wallonne (Belgique), des contrôles sont chaque année organisés en vue de mesurer l'azote nitrique présent dans les parcelles d'agriculteurs situés en zone vulnérable. Les résultats de ces mesures sont comparés à des références annuelles établies pour huit classes d'occupation de sol.En 2016, les références établies par Gembloux Agro-Bio Tech (ULiège) et l'UCL se sont appuyées sur des observations réalisées dans plus de 250 parcelles distribuées dans 41 exploitations agricoles encadrées en matière de gestion de l'azote. Le Service Public de Wallonie a fait contrôler environ 2000 parcelles par des laboratoires agréés. De l'ordre de 80% des exploitations contrôlées ont présenté des résultats conformes. [less ▲]

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See detailDownstream Design for Biobased Processes
Pfennig, Andreas ULg

Conference (2017, May 11)

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See detailAtelier ENMG
WANG, François-Charles ULg

Conference (2017, May 11)

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See detailAn easy route to synthesis black phosphorus at low pressure and soft conditions
Tiouitchi, Ghassane; Hamedoun, Mohammed; El Kenz, Abdallah et al

Conference (2017, May 11)

Black phosphorus a promising candidate for large application, due to his variety of structural and physical properties, can be prepared by a very low-coast reaction route with high purity and ... [more ▼]

Black phosphorus a promising candidate for large application, due to his variety of structural and physical properties, can be prepared by a very low-coast reaction route with high purity and crystallinity. Black phosphorus is prepared from red phosphorus at 873K under reduced pressure using a simple and low cost catalytic system. The quality of crystal with lattice parameters a=3.31Å, b=10.48Å, c=4.37Å can be approved by a series of characterizations like scanning microscopy electron (SEM), energy dispersive spectrometry (EDX), Raman spectroscopy and powder X-rays. The new preparation method of black phosphorus represents an easy, effective and low cost approach to avoid complicated preparative setups, toxic catalysts, or “dirty” flux methods and is of general interest in elemental chemistry. [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)

Detailed reference viewed: 14 (3 ULg)
See detailL'évaluation des acquis de formation
Poumay, Marianne ULg

Conference (2017, May 11)

Cette conférence pose comme complémentaires l'évaluation d'une part des "ressources" (savoirs, savoir-faire et attitudes), d'autre part des compétences (mobilisation et combinaison de ces ressources dans ... [more ▼]

Cette conférence pose comme complémentaires l'évaluation d'une part des "ressources" (savoirs, savoir-faire et attitudes), d'autre part des compétences (mobilisation et combinaison de ces ressources dans des savoir-agir en contexte authentique). Elle présente des modèles et illustrations qui permettent de maximiser l'impact de l'évaluation sur le développement de l'étudiant, en plaçant un accent tout particulier sur la qualité du feedback et les formes de questionnement. [less ▲]

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See detailLes lieux hybrides dans la ville : essai de cartographie
Uyttebrouck, Constance ULg

Conference (2017, May 11)

Les « lieux hybrides », associant activités résidentielles et professionnelles dans un même espace, et dont le développement s’inscrit dans l’évolution de l’habitat et du monde du travail, nécessitent la ... [more ▼]

Les « lieux hybrides », associant activités résidentielles et professionnelles dans un même espace, et dont le développement s’inscrit dans l’évolution de l’habitat et du monde du travail, nécessitent la mise en place de dispositifs régulateurs, au regard des dynamiques de cohésion sociale et de développement urbain. Une production non régulée de tels lieux comporte des incertitudes liées à la mobilité, qui pourraient entraîner un nouveau mouvement d’urbanisation vers la périphérie. La mixité de fonctions qui les caractérise pourrait en outre fragiliser l’accès au logement dans des quartiers soumis à une forte pression immobilière. L’article met en évidence la possibilité de cartographier le parc actuel de lieux hybrides à l’échelle de la région bruxelloise, voire de la métropole, pour visualiser les dynamiques spatiales en jeux. L’objectif est ensuite de mener une étude comparative avec Amsterdam et Stockholm, afin de dégager les facteurs de convergence et de divergence liés à des dynamiques urbaines propres ou à des instruments de régulation spécifiques. Le caractère innovant, et parfois informel, du phénomène complexifie également l’établissement de la cartographie. [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 detailPasser à un SGB pour susciter l'appétit de changement et lutter contre l'inertie ?
Renaville, François ULg

Conference (2017, May 10)

En février 2015, les Bibliothèques de l'Université de Liège sont passées au système de gestion de bibliothèque Alma, moins de 10 ans après une migration vers Aleph et 2 ans après le lancement de la ... [more ▼]

En février 2015, les Bibliothèques de l'Université de Liège sont passées au système de gestion de bibliothèque Alma, moins de 10 ans après une migration vers Aleph et 2 ans après le lancement de la solution discovery Primo. Cette présentation balaye les moments clés du projet Alma, en mettant l'accent sur la composante organisationnelle, la gestion du changement, les attentes et espoirs suscités. [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 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 detailEnergy product and magnetic properties of strontium hexagonal ferrite: experimental and theoretical investigation
Abraime, Brahim; Ait Tamerd, Mohamed; Mahmoud, Abdelfattah ULg et al

Conference (2017, May 10)

The interest toward hard magnetic materials increases in the last years. In order to have the best magnetic properties of these materials, researchers count on the efficiency of different synthesis ... [more ▼]

The interest toward hard magnetic materials increases in the last years. In order to have the best magnetic properties of these materials, researchers count on the efficiency of different synthesis methods. In permanent magnets application, ferrite materials possess a good place among the other magnet families. In permanent magnets field, the more important parameter that describes the magnetic strength of a magnet is the maximum energy product (BH)max. A strong permanent magnet has an important value of (BH)max. In this work, we will study the effect of annealing temperature on maximum energy product and other magnetic properties of Strontium hexaferrite SrFe12O19 synthesized using sol-gel autocombustion method, with different annealing temperatures, characterized using Thermogravimetric analysis (TGA), X-ray diffraction (XRD), scanning electron microscopy (SEM), Mössbauer spectroscopy (MS) and superconducting quantum interference device magnetometer (SQUID). Ab initio calculation for magnetic properties is also performed in order to compare it with low temperature experimental results. [less ▲]

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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 detailLivre de raison, livre de famille. Réflexions méthodologiques sur la diffusion extralittéraire de Gerard du Frattre
Lambert, Adélaïde ULg

Conference (2017, May 10)

Cette communication consistera à présenter le codex Paris, BnF, fr. 12791, un manuscrit personnel entièrement copié par Jacques Le Gros, un marchand de soie parisien, mort en 1551. Outre le récit épique ... [more ▼]

Cette communication consistera à présenter le codex Paris, BnF, fr. 12791, un manuscrit personnel entièrement copié par Jacques Le Gros, un marchand de soie parisien, mort en 1551. Outre le récit épique Gerard du Frattre, le codex contient des pièces portant sur l’actualité sociale et politique du 2e quart du XVIe siècle. À l’aide des travaux portant sur les livres de raison français et sur les livres de famille italiens, il s’agira d’interroger la manière dont ce recueil organique peut être appréhendé et, plus largement, de proposer quelques perspectives de recherche sur la réception des œuvres littéraires françaises dans la sphère de la bourgeoisie marchande. [less ▲]

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See detailHunger Art and the Sensorium
Delville, Michel ULg

Conference (2017, May 10)

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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 detailSpray Drying-­Assisted Synthesis of Na2FePO4F/CB and Na2FePO4F/CNT Composite Cathodes for Lithium Ion Battery
Mahmoud, Abdelfattah ULg; Brisbois; Caes, sebastien et al

Conference (2017, May 08)

Fluorophosphates are considered among the most interesting series of cathode materials for Li/Na-ion batteries. Na2FePO4F, with layered structure and two-dimensional pathways for facile Na+/Li+ transport ... [more ▼]

Fluorophosphates are considered among the most interesting series of cathode materials for Li/Na-ion batteries. Na2FePO4F, with layered structure and two-dimensional pathways for facile Na+/Li+ transport [1], exhibits minimal structural changes (3.7%) upon reduction/oxidation. The average working voltage is 3.3 V versus Li+/Li. However, one of the key drawbacks of Na2FePO4F electrodes is their low intrinsic electronic conductivity. In this work, we report on the synthesis of Na2FePO4F by spray-drying, a technique which is easily scaled-up from the lab- to the industrial-scale and ensures a good homogeneity of all precursors. We are investigating the replacement of the grinding step by the addition of conductive carbon (carbon black and carbon nanotubes) to the solution containing the inorganic precursors of the Na2FePO4F phase in order to prepare Na2FePO4F/CB and Na2FePO4F/CNT with different ratios of CB and CNT (10 and 20%) and enhanced conductivity. The electrochemical performance shows that the addition of CNT improves remarkably the capacity of the NFPF electrode material thanks to better CNT dispersion inside and at the surface of the NFPF particles which enhances the electronic conductivity. Acknowledgements: The authors thank the Walloon Region for support under the “PE Plan Marshall 2.vert” program (BATWAL -1318146). A. Mahmoud is grateful to the Walloon region for a Beware Fellowship Academia 2015-1, RESIBAT n° 1510399. References [1] M. Brisbois, S. Caes, M-T. Sougrati, B. Vertruyen, A. Schrijnemakers, R. Cloots, N. Eshraghi, R-P. Hermann, A. Mahmoud, F. Boschini, Solar Energy Materials & Solar Cells 148 (2015) 11-19. [less ▲]

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See detailValidation of a simplfied method for the crashworthiness of offshore wind turbine jackets using finite elements simulations
Pire, Timothée ULg; Echeverry Jaramillo, Sara ULg; Rigo, Philippe ULg et al

in Guedes Soares, Carlos; Garbatov, Yordan (Eds.) Progress in the Analysis and Design of Marine Structures (2017, May 08)

The work presented in this paper focuses on crashworthiness of jacket foundations used to support offshore wind turbines in moderately deep waters. In a previous research work, the authors have developed ... [more ▼]

The work presented in this paper focuses on crashworthiness of jacket foundations used to support offshore wind turbines in moderately deep waters. In a previous research work, the authors have developed a solver based on analytical formulations, derived from limit plastic analysis, to assess the damage of such foundations when impacted by a ship. The present paper describes the methodology followed to perform numerical validations of the theoretical developments, including a description of the finite element models, the computation hypotheses and the simulations performed using LS-DYNA code. Many parameters describing the collision scenario are investigated, namely the type, the mass, the initial velocity and the trajectory of the striking ship. Some comparisons between analytical and numerical results are finally shown. [less ▲]

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See detailStaaten mit ausgeprägter Regionalautonomie - Fallstudie : Belgien
Behrendt, Christian ULg

Conference (2017, May 05)

Exposé donné à l'invitation du Congrès des pouvoirs locaux et régionaux du Conseil de l'Europe, dans le cadre de la conférence "Pour une réforme territoriale réussie : Causes et méthodes de réformes infra ... [more ▼]

Exposé donné à l'invitation du Congrès des pouvoirs locaux et régionaux du Conseil de l'Europe, dans le cadre de la conférence "Pour une réforme territoriale réussie : Causes et méthodes de réformes infra-nationales dans les pays membres du Conseil de l'Europe", Eupen, Belgique, 5 mai 2017. [less ▲]

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See detailHow microbes network (and are networked) in geological disposal research: a sociological perspective
Van Oudheusden, Michiel ULg; Schröder, Jantine; Turcanu, Catrinel

Conference (2017, May 05)

In MIND subtask 3.2, we ascertain whether and how microbes, microbiologists, and microbiology are enrolled into research on the geological disposal of radioactive waste. We adopt a social studies of ... [more ▼]

In MIND subtask 3.2, we ascertain whether and how microbes, microbiologists, and microbiology are enrolled into research on the geological disposal of radioactive waste. We adopt a social studies of science (actor-network theory) perspective that observes how actors within MIND (e.g. MIND researchers, members of the MIND Implementer Review Board) and outside the project (e.g. geologists, waste management regulators, policy makers) process data and generate insights on the role of microbes in waste disposal, and how these processes elicit challenges and opportunities for enrolment. Examples of the latter include mixed appreciations of the impact of microbial activity on artificial barriers (e.g. negligible vs. substantial), the scope for, and appeal of, institutional uptake of microbiology research (e.g. through the coupling of microbiology research to “the safety case”), and the (re)drawing of disciplinary boundaries (e.g. between microbiology and geology). Drawing on these and related examples, we explore how through projects like MIND, microbes network, and are networked, differently for the joint purpose of radioactive waste disposal. [less ▲]

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See detailObjets directs en kirundi
Tuyubahe, Pascal ULg

Conference (2017, May 05)

Detailed reference viewed: 13 (3 ULg)
See detailTo be plastic is fantastic: delineate coral species niches for assessing their tolerance to changes
Denis, Vianney; Sturaro, Nicolas ULg; Yang, Shan-Hua et al

Conference (2017, May 05)

Climatic and anthropogenic disturbances alter coral reefs by reconfiguring existing coral assemblages. Surviving species are selected by the new environment based on particular traits that they may ... [more ▼]

Climatic and anthropogenic disturbances alter coral reefs by reconfiguring existing coral assemblages. Surviving species are selected by the new environment based on particular traits that they may exhibit, with the plasticity in traits defining ecological strategies associated with contrasting degrees of tolerance to changes. In this process, specialists are expected to tolerate few changes to the environmental conditions and are restricted to specific habitat, while generalists can cope with a wider range of environmental conditions by readjusting traits according to the habitat’s features. Ecological strategies in corals have been exclusively defined according to species’ trait averages, irrespective of individual variations. Challenges representing the acquisition and use of energy have also tended to be oversimplified, specifically by the choice of easy traits in the absence of strong scientific evidence. In this study, we propose a re-examination of strategies in scleractinian corals by focusing on the intraspecific variation of traits. We will investigate how the characteristics of a given species niche can help coral species to tolerate changes. Our multidisciplinary approach will focus on three major characteristics of the coral holobiont (its physiology, trophic ecology, and associated microbiome) which together can define the ecological plasticity of species. This work is of tremendous importance for enhancing the understanding of coral response to environmental changes and for ensuring functions as well as the services of this ecosystem to future generations. [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 ▲]

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See detailFunctional emulsion-templated macroporous polymers via controlled radical polymerization
Mathieu, Kevin ULg; Jérôme, Christine ULg; Debuigne, Antoine ULg

Conference (2017, May 05)

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 emulsion-templated polymerization. In this strategy, a major phase is dispersed in a minor continuous phase containing monomers, cross-linker, initiator and surfactant. The curing of the continuous phase followed by the removal of the dispersed phase leads to a monolith with voids interconnected by pores. Size and number of the latters are influenced by several parameters and especially by the nature of the surfactant. Consequently, we prepared by controlled radical polymerization a series of well-defined amphiphilic copolymers having different hydrophilic-lipophilic balance (HLB) and chain-ends, used it as stabilizers for the emulsion-templated polymerizations and demonstrated the crucial effect of the macromolecular features as well as the concentration on the foam morphology. Secondly, the physical and the chemical anchoring of the macromolecular surfactants at the surface of the pores were also considered for tuning the surface properties of the porous monoliths in one step. This strategy was also implemented with alkyne-terminated copolymers in order to decorate the surface of the cavities with “clickable” moieties which broadens the scope of functional macroporous polymers. [less ▲]

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See detailActivational and organizational disruption of folliculogenesis and estrous cycle caused by exposure to Bisphenol A (BPA) during early postnatal or adult life
Lopez Rodriguez, David ULg; Franssen, Delphine ULg; GERARD, Arlette ULg et al

Conference (2017, May 05)

Our previous studies have shown that an early postnatal exposure to a very low dose of bisphenol A (BPA) disrupts sexual maturation and pubertal timing. However, the long-term effects of such low dose ... [more ▼]

Our previous studies have shown that an early postnatal exposure to a very low dose of bisphenol A (BPA) disrupts sexual maturation and pubertal timing. However, the long-term effects of such low dose exposure as well as the effects of adult exposure have not been studied. One day-old and 90 day-old female rats received daily subcutaneous injections of corn oil (vehicle) or BPA (25ng/kg/d or 5mg/kg/d) for 15 days. The early postnatal exposure to both BPA doses significantly decreased the percentage of females with a regular cycle (BPA-25ng: 51±15%; BPA-5mg: 7±7%; OIL: 86±2%). The estrus cycle alterations were characterized by a decrease in time spent in proestrus (BPA-25ng: 13±3%; BPA-5mg: 12±3%; OIL: 18±3%). During adult exposure, both doses caused a disruption of the estrous cycle characterized by a significant decrease in the average time spent in proestrus (BPA-25ng: 19±2%; BPA-5mg: 17±1%; OIL: 23±1%). This effect was transient as the exposed females showed a regular cycle one month after the last dose of BPA. After adult exposure, we also observed a disruption of folliculogenesis characterized by a significant decrease of antral follicles (BPA-25ng: 21±2%; BPA-5mg: 21±2%; OIL: 36±2%) and increase of atretic follicles (BPA-25ng: 24±4%; BPA-5mg: 26±6%; OIL: 15±1%). GnRH secretion measured ex vivo 24h after adult exposure was moderately affected by BPA. Indeed, GnRH interpulse interval was significantly different when comparing animals exposed to the high or low dose of BPA but not when comparingexposed animals to the control group (BPA-25ng: 42.6±0.5; BPA-5mg: 40.2±0.6%; OIL: 41.1±0,2minutes±SEM). In conclusion, while exposure to BPA produces persistent alterations of the estrous cycle after early postnatal exposure, exposure during adulthood appears to cause activational non-persistent alternations of both the estrous cycle and folliculogenesis. [less ▲]

Detailed reference viewed: 45 (3 ULg)
See detailThe use of stable isotopes in marine animal trophic ecology
Sturaro, Nicolas ULg; Lepoint, Gilles ULg; Frederich, Bruno ULg et al

Conference (2017, May 05)

Stable isotope analysis has been recognised as a useful tool for studying animal diet, identifying trophic relationships, and delineating food web structures as well as their alteration by human ... [more ▼]

Stable isotope analysis has been recognised as a useful tool for studying animal diet, identifying trophic relationships, and delineating food web structures as well as their alteration by human activities. Over the past decade, the number of studies using stable isotopes of carbon and nitrogen in marine trophic ecology has increased rapidly as technological advancements greatly facilitate their use. This tool is now among the most popular in ecology and several fields of investigations have developed, including the extension of analyses to more ‘difficult’ stable isotope ratio measurements such as sulfur, the use of isotope mixing models, and the creation of compound-specific stable isotope analysis. Here, we present three case studies taken from our own investigations and previously published literature. The first investigates seagrass detritus ecosystem in which the coexistence of a rich number of species of crustacean raises the question of whether trophic diversity exist among these species. The second examines the feeding habits of coral reef fish and explores whether habitat choice on the reef and their behaviour emerges as good predictors of diet. The third presents the potential use of stable isotope analysis in studying the nutrition of scleractinian corals, which are complex symbiotic organisms that usually present both autotrophic and heterotrophic pathways. This tool has enhanced our understanding of coral species biology, yet it remains underused. Overall, we aim to provide initial insights into stable isotope analysis for illustrating their utility and potential applications to better understand food web structures and species diet in the waters around Taiwan. [less ▲]

Detailed reference viewed: 173 (2 ULg)
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 ▲]

Detailed reference viewed: 28 (4 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 detailEnsuring consistency of tools dedicated to biodiversity and ecosystem services : case studies
Pécheur, Emilie ULg; Maebe, Laura ULg; Piqueray, Julien

Conference (2017, May 04)

Public awareness regarding key issues of biodiversity and ecosystem services gave rise to several policies aiming at their consideration in human activities. These policies led to a bunch of legal ... [more ▼]

Public awareness regarding key issues of biodiversity and ecosystem services gave rise to several policies aiming at their consideration in human activities. These policies led to a bunch of legal constraints and incentives that are as many tools to preserve and restore both biodiversity and ecosystem services. However, these tools are often activated in a punctual way, following private initiatives or opportunities and without much reflection about the stakes beyond the actors’ own interests. This results in scattered actions, a lack of cohesion in land planning and sometimes conflicts between stakeholders. Yet biodiversity and ecosystem services need a collaborative management, beyond the individualist approach, to ensure the success and continuity of launched projects. Two case studies illustrate the collaborative and structured application of diverse tools by and for a variety of stakeholders willing to respond to specific needs. The first case is biodiversity-oriented, as it concerns the conservation of Bromus grossus, a plant species listed in Annex II of the Natura 2000 “Habitat” directive, which only grows in agroecosystems. The second case study worked on land multi-functionality in three Walloon municipalities, using ecosystem services as a tool for a land consolidation plan. These two examples highlight: 1° the key actors for the launching and cohesion of the projects, 2° the strengthening steps for short and mid-term success and 3° some conflicting elements interfering with coherent development plans. [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 ▲]

Detailed reference viewed: 26 (2 ULg)
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 detailVrai, faux, non-fictif : l’essai comme saisie des mondes contemporains
Claisse, Frédéric ULg

Conference (2017, May 04)

Detailed reference viewed: 18 (0 ULg)
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: 40 (2 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 ▲]

Detailed reference viewed: 18 (1 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: 11 (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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See detailUnusually high sea ice cover influences resource use by benthic invertebrates in coastal Antarctica
Michel, Loïc ULg; Dubois, Philippe; Eleaume, Marc et al

Conference (2017, May 04)

Antarctica currently undergoes strong and contrasted impacts linked with climate change. While the West Antarctic Peninsula is one of the most rapidly warming regions in the world, resulting in sea ice ... [more ▼]

Antarctica currently undergoes strong and contrasted impacts linked with climate change. While the West Antarctic Peninsula is one of the most rapidly warming regions in the world, resulting in sea ice cover decrease, the sea ice cover of East Antarctica unexpectedly tends to increase, possibly in relation with changes in atmospheric circulation. Changes in sea ice cover are likely to influence benthic food web structure through modifications of benthic-pelagic coupling, disruption of benthic production and/or modifications of benthic community structure (i.e. resource availability for benthic consumers). Here, we studied shallow (0-20 m) benthic food web structure on the coasts of Petrels Island (Adélie Land, East Antarctica) during an event of unusually high spatial and temporal (two successive austral summers without seasonal break-up) sea ice cover. Using stable isotope ratios of C and N and the SIAR mixing model, we examined importance of 4 organic matter sources (benthic macroalgae, benthic biofilm, sympagic algae, suspended particulate organic matter) for nutrition of dominant primary consumers and omnivores. 14 invertebrate taxa including sessile and mobile polychaetes, gastropods, bivalves, sea stars, sea urchins and sea cucumbers were studied. Our results indicate that most benthic invertebrates predominantly relied on sympagic algae. Despite its very high abundance, trophic role of benthic biofilm seemed limited. However, interpretation of data was complicated by the peculiar ecophysiological features of Antarctic invertebrates, whose very low metabolic rates could be associated to low isotopic turnover and long time to reach isotopic equilibrium with their food items. Resource use by consumers from Adélie Land markedly differed from literature data about invertebrate diet in coastal Antarctica, suggesting 1) important influence of increased sea ice cover on benthic food web structure and 2) high spatial and/or temporal variation in the feeding habits of studied organisms, likely linked with a high degree of trophic plasticity. Our results provide insights about how Antarctic benthic consumers, which have evolved in an extremely stable environment, might adapt their feeding habits in response to sudden man-driven changes in environmental conditions and trophic resource availability. [less ▲]

Detailed reference viewed: 84 (11 ULg)
See detailControlled synthesis of α-olefins-based copolymers by organocobalt(III) complexes
Demarteau, Jérémy ULg; Debuigne, Antoine ULg; Detrembleur, Christophe ULg

Conference (2017, May 04)

Polyolefins, and ethylene-vinyl acetate (EVA) copolymers in particular, are highly attractive materials that are industrially synthesized by a free radical process for large range of applications from ... [more ▼]

Polyolefins, and ethylene-vinyl acetate (EVA) copolymers in particular, are highly attractive materials that are industrially synthesized by a free radical process for large range of applications from food packaging to coatings. Their production requires drastic synthesis conditions (high pressure and high temperature) and the resulting polymers are generally ill-defined. Controlling the polymerization of these unconjugated monomers remains however extremely difficult because of the lack of stabilizing group on their double bond. Moreover, the preparation of chain-end functionalized polyolefins is actually impossible under these conditions. This communication aims at reporting an efficient platform for the precision design of alpha-olefin-based copolymers through a controlled radical polymerization technique called Cobalt-Mediated Radical Polymerization (CMRP). The latter is based on the reversible deactivation of the radical chains by a cobalt complex bearing acetylacetonate (acac) ligands, which is very efficient under mild experimental conditions. The presentation will focus on three main axes: (i) the synthesis of a novel organocobalt(III) complex useful for the functionalization of the polymer chains, (ii) the preparation of various EVA architectures, (iii) the controlled copolymerization of vinyl acetate with a perfluorinated alkene, i.e. perfluorohexylethylene. The hydrolysis of the pendent esters moieties of these fluorinated copolymers paved the way to their polyvinylalcohol counterparts with a marked amphiphilicity. [less ▲]

Detailed reference viewed: 27 (6 ULg)
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: 61 (3 ULg)
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 ▲]

Detailed reference viewed: 32 (1 ULg)
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 ▲]

Detailed reference viewed: 19 (2 ULg)
Peer Reviewed
See detailPenser l’anticipation par le discours social. Variations sur le radium
Stienon, Valérie ULg

Conference (2017, May 03)

Une véritable fureur du radium s’empare du premier tiers du XXe siècle, sur une période allant de la découverte des rayons X par Röntgen en 1895, de la radioactivité par Becquerel en 1896 puis du radium ... [more ▼]

Une véritable fureur du radium s’empare du premier tiers du XXe siècle, sur une période allant de la découverte des rayons X par Röntgen en 1895, de la radioactivité par Becquerel en 1896 puis du radium par le couple Curie en 1898, jusqu’à la mort de Marie Curie en 1934. Le radium constitue un cas intéressant pour interroger les possibles de la science, l’extension de l’imaginaire social par ses applications au quotidien et ses modalités de mise en récit entre réalité, croyance et fiction. À travers un large corpus d'articles de presse (articles scientifiques, romans-feuilletons, publicités, petites annonces, blagues illustrées) et de romans (aventure, fantastique, espionnage), la communication propose une approche contextuelle et médiatique du récit d'anticipation. La réflexion doit permettre de réévaluer des cadres de réception de l'anticipation souvent limités à l’alternative entre prophétisme du texte supposé visionnaire et obsolescence de la thématique non advenue ou passée de mode. [less ▲]

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See detailMontenegrin ponds and lakes under threat: multiple stressors caused large-scale amphibian decline
Denoël, Mathieu ULg; Kalezić, Miloš; Džukić, Georg et al

Conference (2017, May 03)

Detailed reference viewed: 13 (1 ULg)
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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 detailHybrid Fire Testing: A new approach for fire labs
Sauca, Ana ULg; Gernay, Thomas ULg; Mergny, Elke ULg et al

Poster (2017, May 02)

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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 ▲]

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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.

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See detailMODELISATION D’UN ECHANGEUR A THERMOSIPHONS POUR LA RECUPERATION DE CHALEUR
Le, Van Long ULg; Dumas, Xavier; Ferrand, Ludovic et al

in XIIIème Colloque Interuniversitaire Franco-Québécois sur la Thermique des Systèmes (2017, May)

Le présent travail a pour objectif de modéliser un échangeur à thermosiphons diphasiques pour transporter la chaleur d’un effluent gazeux (c.à.d. gaz de combustion) à haute température (720°C) au système ... [more ▼]

Le présent travail a pour objectif de modéliser un échangeur à thermosiphons diphasiques pour transporter la chaleur d’un effluent gazeux (c.à.d. gaz de combustion) à haute température (720°C) au système ORC (cycle organique de Rankine). Les thermosiphons sont placés dans les gaz de combustion et refroidis par le fluide de travail du système ORC (le Cyclopentane pour le cas actuel). Le débit massique des fumées et la puissance thermique de l’échangeur sont respectivement imposés de 21 kg/s et de 4.022 MWth. Le fluide organique s’évapore à une température de 200°C et quitte l’évaporateur sans surchauffe (vapeur saturée). Le modèle de simulation développé dans le logiciel EES (Engineering Equation Solver) est capable de déterminer le nombre nécessaiare de thermosiphons. L’influence des pas transversaux et longitudinaux de l’échangeur sur le nombre de thermosiphons et la perte de charge des fumées est également examinée pour les dispositions quinconces et alignées des tubes de thermosiphons. [less ▲]

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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 ▲]

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