References of "Scientific congresses and symposiums"
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See detailThat’s embarrassing! Effects of Brand Anthropomorphism on Intimate Disclosure
Gretry, Anaïs ULg; Horváth, Csilla; Belei, Nina

Conference (2016, May)

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See detailThe Dark Side of Customer Participation: The Antecedents of Customer Participation Stress
Treger, Stephanie; Büttgen, Marion; Schumann, Jan Hendrik et al

Conference (2016, May)

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See detailBinary Phase Behavior of tripalmitoylglycerol and 1,3-dipalmitoyl-2-stearoyl-sn-glycerol
Bhaggan, K.; Smith, K. W.; Blecker, Christophe ULg et al

Poster (2016, May)

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See detailEn quoi l'ajout d'un élément de gamification (badges) impacte la réalisation des tests d'entraînement ?
Marique, Pierre-Xavier ULg; Van de Poël, Jean-François ULg; Hoebeke, Maryse ULg

Conference (2016, May)

Le département de physique de l’Université de Liège a développé un outil de soutien à l’apprentissage pour le cours de physique à destination des étudiants inscrits en première année de médecine. Le choix ... [more ▼]

Le département de physique de l’Université de Liège a développé un outil de soutien à l’apprentissage pour le cours de physique à destination des étudiants inscrits en première année de médecine. Le choix s’est porté sur une plateforme en ligne afin qu’elle soit accessible à chaque instant et de n’importe quel endroit, moyennant une connexion internet. L’étudiant, interrogé sous forme de questions à choix multiples, peut notamment utiliser un simulateur d’examens. Il peut à tout moment générer un test selon trois paramètres : la ou les matières qu’il souhaite travailler, le temps qu’il désire y consacrer et le niveau de maitrise qu’il souhaite atteindre. Dès lors, un test d’entrainement est généré automatiquement selon les critères choisis. L’étudiant peut visualiser son état d’avancement dans la matière grâce à une série de badges qu’il est invité à collecter. Une fois certains badges acquis, l’apprenant a la possibilité de télécharger un « pass » personnel lui donnant accès à une séance de simulation d’examen organisée en amphithéâtre. Cette étude présentera les premiers résultats de cette expérimentation. La corrélation avec les notes obtenues à l’examen ainsi que l’impact de la mise en place des badges dans le dispositif d’un point de vue motivationnel seront étudiés. [less ▲]

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See detailL’accompagnement des demandeurs d’emploi par les intermédiaires du marché du travail : une triple opération de sélection
Gérard, Julie ULg; Beuker, Laura ULg

Conference (2016, May)

En 1997, la Convention 181 de l’Organisation internationale du travail sonne le glas du monopole public en matière de placement. Elle invite les services publics de l’emploi et les opérateurs privés à ... [more ▼]

En 1997, la Convention 181 de l’Organisation internationale du travail sonne le glas du monopole public en matière de placement. Elle invite les services publics de l’emploi et les opérateurs privés à collaborer pour fournir un accompagnement plus efficace aux demandeurs d’emploi. Cette collaboration s’inscrit dans le cadre d’une entente contractuelle où les services de l’emploi confient l’exploitation et la gestion de certaines de leurs activités à des prestataires privés au sein de partenariats publicsprivés. Qu’il s’agisse des services publics de l’emploi ou des prestataires privés, tous deux ont pour mission d’assurer l’insertion socioprofessionnelle des demandeurs d’emploi en tant que généralistes, ou spécialistes de l’employabilité. Elle s’inscrit dans la stratégie d’EU2020 et contribue à l’atteinte d’un taux d’emploi de 73,2% pour 2020. À l’aide de trois études de cas réalisées auprès du service public wallon et de deux prestataires privés exerçant en Région wallonne, nous démontrerons que cette mission d’accompagnement s’exerce au prix d’une triple sélection : une première réalisée par le politique, via la définition de publics cibles prioritaires ; une seconde opérée par les agents du service public dans leurs pratiques professionnelles d’accompagnement ; une troisième effectuée par les prestataires privés en fonction de critères objectifs et/ou subjectifs. Pour étudier la mise en oeuvre et l’effet de ces opérations de tri, nous nous inscrirons dans une approche pragmatique. Appuyé sur une étude empirique constituée d’entretiens semi-directifs (N = 45), d’observations d’interactions (N = 149) et de discussions informelles, nous montrerons les conséquences globales de ces tris pour les demandeurs d’emploi. En ne sélectionnant que les plus employables des inemployables, l’opération d’accompagnement ne serait-elle finalement qu’une agitation, et non pas une véritable mise à l’emploi ? [less ▲]

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See detailInteraction entre la zone endommagée autour d’un tunnel et son soutènement – Simulation numérique
Charlier, Robert ULg; Sillen, Xavier; Li, Xiangling et al

Conference (2016, May)

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See detailFrom Metabolomics Study of Age-Related Macular Degeneration (AMD) to the Development of New Pyruvate Dehydrogenase Kinase Inhibitors (PDK)
Arslan, Deniz ULg; Schoumacher, Matthieu ULg; Pirotte, Bernard ULg et al

Poster (2016, May)

Age-related macular degeneration (AMD) is a leading cause of blindness in the elderly population of industrialized countries. This blindness results from the deterioration of the macula, a small part of ... [more ▼]

Age-related macular degeneration (AMD) is a leading cause of blindness in the elderly population of industrialized countries. This blindness results from the deterioration of the macula, a small part of the retina specialized for the high-acuity vision. Exudative AMD, called “wet”, is characterized by the formation of new blood vessels growing under the retina according to a process named choroidal neovascularization (CNV). Currently, the aetiology and pathogenesis of AMD remain unclear. Nevertheless, a recent metabolomics study performed on the serum of “wet” AMD patients and on a CNV murine model, that mimics the effect of “wet” AMD, have demonstrated that lactate level is clearly involved in the severity of the pathology as well as the relationship between lactate, CNV and AMD. According to this result, we suggest a new therapeutic approach of AMD based on the normalization of blood lactate level. The modulation of the lactate plasma concentration by treatment of the animals with synthetic compounds and more specifically Pyruvate Dehydrogenase Kinase (PDK) inhibitors significantly decrease the CNV. PDK and its four isoforms (PDK1-4) regulate the activity of the pyruvate dehydrogenase complex (PDH), a mitochondrial enzyme that plays a major role in the metabolic pathway of glucose, by reversible phosphorylation. Starting from these results, development of new PDK inhibitors could open the way to innovative treatment opportunities in AMD disease. Different analogues of (R)-3,3,3-trifluoro-2-hydroxy-2-methylpropanamide (fig.1) have been already synthetized and pharmacological evaluation is currently in progress. According to the results obtained, various pharmacomodulations will be investigated [less ▲]

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See detailJeunes fugueurs en Belgique : Indicateurs de risque et de protection dans les signalements
Courtain, Audrey ULg; Glowacz, Fabienne ULg

Conference (2016, May)

Chaque année, 1% des foyers européens vit la fugue d’un de ses membres de moins de 18 ans. Au 2 janvier 2014, plus de onze mille jeunes français étaient recherchés comme fugueurs ; avec près de 50.000 ... [more ▼]

Chaque année, 1% des foyers européens vit la fugue d’un de ses membres de moins de 18 ans. Au 2 janvier 2014, plus de onze mille jeunes français étaient recherchés comme fugueurs ; avec près de 50.000 fugues de mineurs français par an. En Belgique, sur les années 2013-2014, l’organisme Child Focus s’est vu confier près de 1700 dossiers de fugues de mineurs. Child Focus - Fondation pour Enfants Disparus et Sexuellement Exploités – a été créée à la suite de l’affaire Dutroux, et traite des dossiers de disparitions de mineurs (enlèvements par un tiers, enlèvements parentaux, fugues) et d’exploitation sexuelle de mineurs. Généralement contacté par la famille du jeune ou par la police, Child Focus ne peut ouvrir un dossier de fugue qu’à la suite d’un procès-verbal. Les dossiers de fugues de mineurs ouverts auprès de Child Focus constitueraient un cinquième des fugues enregistrées par la police belge. Ces dossiers, de par leur contenu, permettent d’envisager trois axes de recherche. Le premier axe porte sur le profil des jeunes signalés en fugue (âge, sexe, contexte familial, scolarité,…). Le second axe porte sur le profil du signalant (père, mère, famille élargie, police,…). Le troisième axe porte sur les indicateurs de risque et de protection que les signalants expriment auprès de Child Focus lorsqu’ils évoquent le jeune en fugue (consommation de drogue, délinquance, santé mentale,…). Ces trois axes sont étudiés à partir de deux recherches empiriques, la première portant sur les 1700 dossiers des années 2013-2014, et la seconde portant sur 200 de ces dossiers, dont nous donnerons les résultats préliminaires. Enfin, par ces recherches, nous proposons d’évaluer la portée des filtres et de la black box permettant de comprendre comment et pourquoi certains cas de fugue sont davantage susceptibles d’être confiés à Child Focus que d’autres. [less ▲]

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See detailChitosan-based nanofibers mats for tissue engineering
Aqil, Abdelhafid ULg; Croisier, Florence ULg; Colige, Alain ULg et al

Conference (2016, May)

Polymer hydrogels resemble the natural living tissue due to their high water content and soft consistency. They find many applications in the design and production of contact and intraocular lenses ... [more ▼]

Polymer hydrogels resemble the natural living tissue due to their high water content and soft consistency. They find many applications in the design and production of contact and intraocular lenses, biosensors membranes, matrices for repairing and regenerating a wide diversity of tissues and organs. Polysaccharides such as chitosan and hyaluronic acid based hydrogels have shown a great potential for biomedical and pharmaceutical applications, on account of their remarkable compatibility with physiological medium. Besides, it is degraded in a physiological environment into non-toxic products, which make them outstanding candidates for short- to medium-term applications, especially for tissue engineering. In this respect, the preparation of nanometric fibers mats based on this polysaccharide are highly interesting as such structure mimics the one of skin extracellular matrix. Such nanofibrous materials can be prepared by electrospinning (Figure 1). This technique uses a high voltage to create an electrically charged jet of polymer solution to obtain polymer fibers ranging from nanometers to a few microns in diameter. We thus have investigated strategies allowing to generate chitosan based nanofiber mats exhibiting a mechanical resistance strong enough to be easily handled while keeping the peculiar features of chitosan hydrogels favoring the interaction with cells and soft tissues to provide efficient tissue reconstruction. In a first strategy, polysaccharide-based nanofibers with a multilayered structure were prepared by combining electrospinning (ESP) and layer-by-layer (LBL) deposition techniques. Elastic nanofibers bearing charges at their surface were firstly prepared by electrospinning poly(ε-caprolactone) (PCL) with a polyelectrolyte precursor. After activation by adjusting the pH, the layer-by-layer deposition of chitosan and hyaluronic acid, can be used to coat the electrospun fibers. A multilayered structure is then achieved by alternating the deposition of the positively charged chitosan with the deposition of a negatively charged polyelectrolyte. These novel polysaccharide-coated PCL fiber mats remarkably combine the mechanical resistance typical of the core material (PCL) – particularly in the hydrated state –, with the surface properties of chitosan. Besides, crosslinked nanofibrous mats of chitosan and polyethylene oxide blends, were successfully prepared via electrospinning technique followed by heat mediated chemical crosslinking. This chemical cross-linking allows adjusting the mechanical resistance of the mats while preserving their biocompatibility. In both cases, the control of the nanofiber structure offered by the electrospinning technology, makes the developed processes very promising to precisely design biomaterials for tissue engineering. Preliminary cell culture tests corroborate the potential use of such systems in wound healing applications. [less ▲]

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See detailDétection de la mémoire ischémique myocardique par le 99mTc-fucoïdane : validation pré-clinique.
Mikail, N; Louedec, L; Aid, R et al

Conference (2016, May)

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See detailDélinquance et désistance : quelle méthodologie de recherche ?
Puglia, Rosa ULg; Glowacz, Fabienne ULg

Conference (2016, May)

Dans la littérature concernant la délinquance, les auteurs se sont, au départ, principalement intéressés aux raisons qui poussent les individus à commettre des délits mais peu ont tenté de comprendre ... [more ▼]

Dans la littérature concernant la délinquance, les auteurs se sont, au départ, principalement intéressés aux raisons qui poussent les individus à commettre des délits mais peu ont tenté de comprendre pourquoi et comment certains individus, qui ont commis des actes délictueux, sortent de la délinquance. En effet, la désistance, c’est-à-dire le processus de sortie de la délinquance, a longtemps été négligée par les chercheurs. À partir des années '50, un intérêt croissant pour ce domaine de recherche apparaît. La désistance devient alors un sujet d’étude indépendant et non plus un appendice de la recherche sur les carrières délinquantes (Mohammed, 2012). Malgré l’intérêt croissant pour ce champ de recherche, de nombreuses zones d’ombre persistent. Sur base d’une recherche longitudinale réalisée sur une population d’adultes en émergence délinquants (17-25ans), nous tentons d’avoir une approche holistique de la désistance. Celle-ci est définie ici comme un processus impliquant des changements individuels et sociaux, qui s’inscrit dans le temps et qui peut être marqué par des réitérations d’actes délinquants. Dans notre étude, la désistance sera étudiée à travers une approche mixte combinant un récit de vie et des questionnaires. L’approche narrative est essentielle dans notre recherche, elle permettra d’appréhender les transformations identitaires, les schémas de changement et de stabilité dans le parcours de vie et dans la trajectoire délinquante. Elle permettra également de mettre en avant les facteurs internes et externes identifiés comme des facteurs de désistance. Par ailleurs, comme Maruna (2001), nous posons l’hypothèse que les persistants et les désistants sont des individus similaires qui se trouvent à des stades différents du processus de changement. C’est pourquoi, en toile de fond, la désistance sera envisagée à travers le modèle transthéorique de Proshaska et DiClemente (1982) où différentes étapes se succèdent avant l’arrêt du comportement problématique. [less ▲]

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See detailHow Service Managers Can Shape Frontline Employees' Organizational Values to Reduce Person-Role Conflicts
Selzer, Veronika Luisa; Schumann, Jan Hendrik; Büttgen, Marion et al

Conference (2016, May)

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See detailQuand les cultures alimentaires se rencontrent. (Re)définition et transmission des pratiques dans un atelier de cuisine arabe en Italie.
Mescoli, Elsa ULg

Conference (2016, May)

Le déplacement des individus est toujours accompagné par le mouvement de choses et pratiques qui voyagent avec eux. Ce fait permet d’étudier la culture matérielle engagée par la mobilité des personnes ... [more ▼]

Le déplacement des individus est toujours accompagné par le mouvement de choses et pratiques qui voyagent avec eux. Ce fait permet d’étudier la culture matérielle engagée par la mobilité des personnes. Cette culture inclut les habitudes alimentaires, qui font l’objet de plusieurs recherches portées sur les changements culinaires (ou les résistances) déterminés par la migration. Loin d’être le seul enjeu constaté lorsque l'on étudie les pratiques alimentaires des migrants – qui par ailleurs sont souvent considérées comme statiques avant la migration –, cette question amène souvent à négliger d'autres dynamiques importantes qui sont également à l’œuvre. Telles que celles qui se produisent lorsque des cultures alimentaires qui se prétendent différentes se rencontrent, ce qui conduit à la mobilisation d’appartenances par les membres de différents groupes culturels qui veulent prendre une position spécifique chacun par rapport à l'autre. Mon exposé vise à analyser cette rencontre. L'hypothèse est qu’elle façonne un espace qui correspond à un tertium quid, une dimension où les frontières des cultures alimentaires peuvent également s’atténuer en raison notamment de la (re)définition et de la transmission des pratiques. Afin de décrire ces dynamiques, je présenterai les données ethnographiques collectées durant un terrain ethnographique porté sur les pratiques culinaires d'un groupe de femmes migrantes marocaines vivant dans la périphérie de Milan, en Italie. Je vais également appuyer ma présentation sur des matériaux visuels recueillis lors des observations et des entretiens dans les maisons ainsi que dans des événements publics tel qu’un cours de cuisine arabe. [less ▲]

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See detailPRODUCTION OF BIOFUELS AND BIOBASED COMPOUNDS IN URBAN BIOREFINERIES: A STRATEGY TO MANAGE WASTE IN WALLONIA?
Richel, Aurore ULg; Haubruge, Eric ULg; Jacquet, Nicolas ULg

Conference (2016, May)

“Urban biorefining” is an original concept aiming at using urban wastes (household wastes, municipal wastes, industrial liquid and/or solid residues and side-products, etc.), mainly of vegetal origin, for ... [more ▼]

“Urban biorefining” is an original concept aiming at using urban wastes (household wastes, municipal wastes, industrial liquid and/or solid residues and side-products, etc.), mainly of vegetal origin, for the production of an array of biofuels and bioproducts. This “urban biorefining” concept fits particularly with the economic, geographic and politic contexts and constraints of the Walloon Region (south part of Belgium). Indeed, Walloon Region is a very small territory (area of about 6,504 sq mi) with a temperate climate. Supply feedstock, mainly arising form forestry and agriculture, are thus rather restricted, submitted to importation, and subjected to non-standardized quality. Several examples of our regional strategy, still available on an industrial scale, are herein proposed and detailed. [less ▲]

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See detailTowards an Novel Stiff String Model for the Torque and Drag Problem
Huynen, Alexandre ULg

Conference (2016, May)

The petroleum industry relies on several kilometer long drillstrings to transmit the axial force and torque necessary to drill the rock formations and reach deep hydrocarbon reservoirs. The assessment of ... [more ▼]

The petroleum industry relies on several kilometer long drillstrings to transmit the axial force and torque necessary to drill the rock formations and reach deep hydrocarbon reservoirs. The assessment of the energy loss along the drillstring, known as the torque and drag problem, plays an essential role in well planning and drilling as the friction appearing at the contacts between the drillstring and the borehole may dramatically increase the costs or, even, be a limiting factor in some configurations. The identification of the number of contacts as well as their positions and extents constitutes the central concern of this question. The nonlinearities associated with the large deflection of the drillstring and the non-penetration condition as well as the a priori unknown number of contacts, however, make the use of conventional numerical tools rather inefficient. To circumvent these difficulties, a simplified stiff string model is derived. Partitioning the global problem in segments of drillstring either in continuous contact with the borehole or free of contact between their extremities, the originality of the proposed formulation lies in the descripion of the drillstring deflection as perturbation of the well-path. [less ▲]

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See detailElectromagnetic Investigation of the Pb-Zn deposit of Lontzen, Belgium
Evrard, Maxime ULg; Pirard, Eric ULg; Nguyen, Frédéric ULg

in First International Conference: MINING IN EUROPE, ABTSRACT volume (2016, May)

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See detailInflammation et alimentation: des pistes intéressantes
Knapp, Emilie ULg; Guyot, Hugues ULg

in SNGTV (Ed.) Journées Nationales des GTV: Nutrition et pratique vétérinaire, du b.a.-ba à l'innonvation (2016, May)

Les processus inflammatoires sont déclenchés lors d'une agression et font partie intégrante du système immunitaire. La problématique réside lorsque ces processus inflammatoires ne sont plus contrôlés et ... [more ▼]

Les processus inflammatoires sont déclenchés lors d'une agression et font partie intégrante du système immunitaire. La problématique réside lorsque ces processus inflammatoires ne sont plus contrôlés et provoquent plus de lésions que l'agression elle-même. Cette inadéquation des réactions inflammatoires aggravent souvent des pathologies comme les mammites, les métrites ou les pathologies métaboliques. La quantité et la qualité de l'alimentation, ainsi que le statut métabolique sont des points majeurs de régulation du système inflammatoire. En effet, de nombreuses molécules intervenant dans l'inflammation sont des protéines synthétisées par le foie ou sont dérivés des acides gras alimentaires. En début de lactation, la mobilisation graisseuse et les corps cétoniques ont une action directe sur l'activité inflammatoire ce qui expliquent l'état de stress oxydatif, la chute d'immunité ainsi que l'état pro-inflammatoire des vaches en post-partum. La digestion ruminale et intestinale des hydrates de carbone et des protéines peuvent également provoquer et réguler l'état inflammatoire systémique du ruminant. L'acidose chronique en est un exemple, cependant, l'alcalose et la mal-digestion des fibres peuvent également provoquer de l'inflammation. En pratique, il existe des paramètres qui permettent d'évaluer l'inflammation d'un animal et d'un troupeau. A l'aide d'une prise de sang et de dosage des protéines totales plasmatiques et sériques on pourra facilement et à des coûts limités, mesurer la présence d'inflammation aiguë ou chronique. La présence d'inflammation chronique est un facteur de risque sous-jacent important dans nos troupeaux de vaches laitières puisqu'il concerne environ 25% des troupeaux qui ont présenté des problèmes de défaut d’efficience alimentaire. Dans les troupeaux avec des signes cliniques de type amaigrissement, sous-production, mal-digestion des fibres et inflammation chronique, l'acidose chronique n'a été diagnostiquée que sur 5% des vaches alors que l'inactivité ruminale a été montrée sur 40% des animaux. Cette inactivité est souvent liée à un déficit en matière organique fermentescible couplée avec un excès de protéines fermentescible ce qui entraine des pH élevés et diminue la multiplication de la flore du rumen. L'analyse du jus de rumen, couplée avec celle des protéines totales permet dans la plupart des cas de poser un diagnostic et de discriminer les cas de SARA des cas de maldigestion et adapter correctement la ration. [less ▲]

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See detailElucidating diversity of thin filamentous mat-forming Antarctic cyanobacteria
Lara, Yannick ULg; Durieu, Benoit ULg; Deblander, Victor ULg et al

Poster (2016, April 29)

Freshwater ecosystems range from glacial cryoecosystems, ice shelf meltwater ponds to perennially ice-covered lakes where conspicuous benthic microbial mat communities constitute most of the biomass. In ... [more ▼]

Freshwater ecosystems range from glacial cryoecosystems, ice shelf meltwater ponds to perennially ice-covered lakes where conspicuous benthic microbial mat communities constitute most of the biomass. In these mats, cyanobacteria form matrices that shelter other organisms, and carry out the primary production. Narrow filamentous cyanobacteria belonging to the genera Leptolyngbya and Phormidium are especially abundant in Antarctic microbial mats and are essential for the formation of matrix. However, the lack of morphological criteria and the small cell size of cyanobacteria belonging to these two genera make their identification problematic. Indeed, they are known as polyphyletic taxa according to botanical and bacteriological criteria. The characterization of strains is the first step for an assessment of the real diversity and for understanding their role in the environment. We designed a polyphasic approach that combines molecular analyses, environmental physiology experiments and microscopic observations. Briefly, we amplified and sequenced three loci (16S rRNA, ITS, and rpoC1) for 31 strains of Leptolyngbya and Phormidium. We performed whole genome sequencing for five strains. Cultures at different stage were observed by light and epifluorescence microscopy. Finally, selected strains were grown in nitrogen-limited. The Leptolyngbya and Phormidium strains were distributed into four lineages. Phylogenetic trees supported the distribution of P. priestleyi strains into at least two potentially new lineages, and L. antarctica strains were separated into one endemic and one cosmopolitan lineage. This was supported by the microscopic observations of 1-year old cultures. Genome analyses revealed the presence of sequences related to the production of secondary metabolites in strains from two of the studied lineages. Secondary metabolites are often known for their antimicrobial activities. Such properties would partly explain how cyanobacterial mats survive to predation and degradation by other bacteria. This work provides the first building block to the understanding of survival strategies developed by mat-forming cyanobacteria and how they succeeded as the most abundant phototrophs on the Antarctic continent. This work was realized in the frame of the BelSPo project CCAMBIO. [less ▲]

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See detailThe CCAMBIO project to characterize the biodiversity and distribution of microorganisms in microbial mats of Antarctic lakes
Durieu, Benoit ULg; Lara, Yannick ULg; Obbels, Dagmar et al

Poster (2016, April 29)

The BelSPO project CCAMBIO aims to study the biogeographical distribution of microorganisms in lacustrine microbial mats using a combination of techniques including microscopical observations (light and ... [more ▼]

The BelSPO project CCAMBIO aims to study the biogeographical distribution of microorganisms in lacustrine microbial mats using a combination of techniques including microscopical observations (light and electronic microscopy), strain isolation, and molecular diversity assessment using Next Generation Sequencing. The samples were collected in different Antarctic and sub-Antarctic biogeographical regions. A detailed microscopic study of the Antarctic diatom diversity allowed to revise a number of taxa and discover new ones. A multivariate analysis of diatoms showed that these regions hosted different diatom flora. Endemic diatom taxa were also observed, and a multigene molecular phylogeny of Pinnularia borealis showed a high genetic diversity. Pilot studies were conducted for the microeukaryotes and cyanobacteria to select NGS protocols and bioinformatic pipelines. Preliminary multivariate analysis of over 100 samples revealed that distinct biogeographic zones could be recognized in both the prokaryote and eukaryote data, which is in agreement with the classical subdivision of the Antarctic Realm into Maritime Antarctica, Continental Antarctica and the Sub-Antarctic Islands generally observed in plants and animals. Moreover, Sub-Antarctic assemblages harboured more complex foodwebs, with quite diverse metazoan groups. Lakes on the continent, however, were characterised by fewer metazoan groups and a greater importance of microbial herbivores and secondary consumers, including a relative high diversity of ciliates and tardigrades. Variation partitioning analysis revealed that spatial variables that approximated large-scale regional contrasts in historical (e.g. deglaciation history, geological origin) and climatic factors (e.g. mean annual air temperature) significantly explained the largest portion of the observed variation in community structure for eukaryotes, while in the prokaryote data environmental gradients related to conductivity were more important. In a first analysis of microbial mats from five Antarctic lakes and an aquatic biofilm from the Sub-Antarctic, the majority of the cyanobacterial OTUs retrieved were related to filamentous taxa such as Leptolyngbya and Phormidium, which are common genera in Antarctic lacustrine microbial mats. However, other phylotypes related to different taxa such as Geitlerinema, Pseudanabaena, Synechococcus, Chamaesiphon, Calothrix and Coleodesmium were also found. Results revealed a higher diversity than what had been reported using traditional methods based on microscopic observations and cultivation and also highlighted remarkable differences between the cyanobacterial communities of the studied lakes. In the next months, the molecular diversity data will be deposited into the “Microbial Antarctic Resource System (MARS)” presently developed into the webportal ‘biodiversity.aq’. The better knowledge of the diversity and distribution of microorganisms will contribute to a better assessment of their resilience and local/regional responses to global change. [less ▲]

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See detailLe droit du travail (re)visité par la Cour constitutionnelle
Kéfer, Fabienne ULg

in Boufflette, Sophie (Ed.) La cour constitutionnelle. De l'art de modeler de droit pour préserver l'égalité (2016, April 29)

L'étude porte sur le rôle de la Cour constitutionnelle dans l’édification du droit du travail. Arrêt après arrêt, elle consolide la norme attaquée ou au contraire redessine – ou presse le législateur de ... [more ▼]

L'étude porte sur le rôle de la Cour constitutionnelle dans l’édification du droit du travail. Arrêt après arrêt, elle consolide la norme attaquée ou au contraire redessine – ou presse le législateur de redessiner – les contours de cette branche du droit fortement marquée par son histoire. Elle se penche sur un peu plus de trente arrêts prononcés par la Cour constitutionnelle, principalement depuis 2008, dans les domaines suivants : le travail à temps partiel (chapitre 1), le droit de la non-discrimination (chapitre 2), certaines questions intéressant le licenciement, à savoir la durée du préavis, les mesures destinées à stimuler l’employabilité, la motivation, la notion de rémunération en cours en cas de réduction temporaire des prestations de travail, et l’indemnité d’éviction du représentant de commerce (chapitres 3 à 7), les distinctions entre employés et ouvriers autres que les conditions de licenciement (chapitre 8), la procédure de réorganisation judiciaire (chapitre 9) et la prescription (chapitre 10). [less ▲]

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See detailLa critique génétique dans la collection "Poétique"
Lorent, Fanny ULg

Conference (2016, April 29)

La critique génétique est, comme le dit bien Jean-Louis Jeannelle, une « théorie en quête d’elle-même » , tiraillée entre la tradition philologique et les avancées structuralistes. Elle doit sans cesse, à ... [more ▼]

La critique génétique est, comme le dit bien Jean-Louis Jeannelle, une « théorie en quête d’elle-même » , tiraillée entre la tradition philologique et les avancées structuralistes. Elle doit sans cesse, à la fois, se défaire des suspicions positivistes qui pèsent sur elle et justifier son appartenance possible à la (une ?) poétique . Nous voudrions étudier, dans cette communication, les mécanismes de légitimation de cette discipline aux contours épistémologiques complexes au sein même de la collection « Poétique », qui accueillit, en 1998, Les brouillons de soi de Philippe Lejeune et, en 2011, Logiques du brouillon de Daniel Ferrer. Comment les auteurs vont-ils, dans leur ouvrage, justifier leur parution au sein d’une collection dont les présupposés théoriques semblent, a priori, contraires à ceux présidant à leur travail ? Quelles en sont alors les implications méthodologiques, pour chacune des deux disciplines ? [less ▲]

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See detailPhysical activity: an unknown concept
Cloes, Marc ULg

Conference (2016, April 29)

Physical educators do not have necesseraly good representations about physical activity and sedentariness. During the presentation, participants will be involved in an interactive process aiming to ... [more ▼]

Physical educators do not have necesseraly good representations about physical activity and sedentariness. During the presentation, participants will be involved in an interactive process aiming to underline the main concepts that they should use in order to become effective agents of physical activity promotion. [less ▲]

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See detailUse of stable isotope ratios to delineate coastal benthic food web structure in Adélie Land (East Antarctica)
Michel, Loïc ULg; Dubois, Philippe; Eleaume, Marc et al

Poster (2016, April 29)

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, in some parts of East Antarctica sea ice cover 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, N and S, we examined importance of several organic matter sources (benthic macroalgae, benthic biofilm, sympagic algae, suspended particulate organic matter and penguin guano) for nutrition of over 20 taxa of benthic invertebrates (sponges, sea anemones, nemerteans, sessile and mobile polychaetes, gastropods, bivalves, sipunculids, pycnogonids, amphipods, sea stars, sea urchins and sea cucumbers) spanning most present functional guilds. 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 changes in environmental conditions and trophic resource availability. [less ▲]

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See detailPercevoir et reconnaître des symboles. La théorie de la représentation iconique de Dominic Lopes.
Hagelstein, Maud ULg

Conference (2016, April 28)

Perceiving and recognizing symbols. Dominic Lopes’ theory of iconic representation. In his works on the epistemological value of images (Understanding Pictures - 1996), Dominic Lopes (Department of ... [more ▼]

Perceiving and recognizing symbols. Dominic Lopes’ theory of iconic representation. In his works on the epistemological value of images (Understanding Pictures - 1996), Dominic Lopes (Department of Philosophy - University of British Columbia) develops an analytical aesthetics primarily concerned with iconic representation. His analysis distinguishes two models of iconic representation comprehension. In the first model, inspired by perceptual approaches like that of Richard Wollheim, the process of image recognition is rooted in perception (to sum it up: perceptualism embraces the idea of « likeness » between the image and what it represents). One of this model’s shortcomings, however, is that it too readily assumes that perception can be a natural, straightforward process. Indeed, iconic representation can not be understood through perception alone, as vision is of course influenced by cultural and, most of all, cognitive processes. A representative model thus needs to account for the ways in which iconic recognition differs from ordinary visual recognition. In the second model, which build off of symbolic approaches like that of Nelson Goodman, iconic representation works the same way as other types of symbols, particularly linguistic ones. Thus, this approach considers the similarities between images and language (representations which are both affected by processes of denotation and predication). However, we all know how strongly image theoreticians have been resisting the linguistic paradigm (iconic turn topic): some worry about overlooking the image’s semantic density in favor of its « simple » descriptive quality. Lopes finds a path between these two models by developing a « theory of aspect recognition », which incorporates perceptive elements into a symbolic structure. According to Lopes, if we agree that images belong to symbolic systems of denotation, then « they might be symbols for which the reference is dependent on the carrying out of perceptive aptitudes », a claim which my talk will explore. I will also discuss how Lopes’ theory accounts for skills acquisition (the capacity to recognize) through images, and shows how images help these skills progressively develop. [less ▲]

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See detailModelling of long-term deep renovation strategies for the Belgian building stock
Ruellan, Guirec ULg

Poster (2016, April 28)

To achieve the EU energy targets for 2050, the construction sector has to perform major transformations. In Belgium, the majority of building stock is particularly old and energy inefficient. The high ... [more ▼]

To achieve the EU energy targets for 2050, the construction sector has to perform major transformations. In Belgium, the majority of building stock is particularly old and energy inefficient. The high performance of new constructions represented in the nearly zero energy buildings target is not sufficient to ensure the efficiency of the overall building sector. Therefore, it is crucial to put in place a progressive renovation policy. Despite the different renovation strategies and projects that took place in the recent year in Belgium, the overall renovation rate remains almost stable for the last ten years. This study focuses on the renovation market in Belgium and analyzes the factors that influence the evolution of the renovation rate. The objective is the identification and development of effective strategies bypass that leads to increased renovation rates in Belgium. The research methodology is based on an iterative process, based on a systematic literature review of Flemish and Walloon projects, publications and policy. These first work package will allow to identify factors influencing the renovation rate and in other hand to build a model of the existing building stock. Impacts of the influencing factors on the building stock are simulated in the fourth work package in order to propose an action plan in the last part. Three mains outcomes are expected: A model of the existing building stock in Belgium and its retrofit potential, a simulation of the effects of different strategies used to increase the renovation rate in Belgium and a theoretical action plan on strategies to increase the rate of renovation in Belgium. These results are necessary to inform and support the decision making of policy makers, municipalities and operational planning authorities across Belgium. [less ▲]

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See detailLa ligne et la boucle. Michel Strogoff ou l'involution
Durand, Pascal ULg

Conference (2016, April 28)

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See detailPrêt "coup de pouce": un nouvel incitant fiscal wallon pour le financement des entreprises débutantes
Bourgeois, Marc ULg; Pace, Xavier ULg

in Bourgeois, Marc (Ed.) Les incitants fiscaux pour les PME - actualités et aspects comptables (2016, April 28)

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See detailAdministration of Third-Party Mesenchymal Stromal Cells at the Time of Kidney Transplantation: Interim Safety Analysis at One-Year Follow-Up
Erpicum, Pauline ULg; WEEKERS, Laurent ULg; DETRY, Olivier ULg et al

Conference (2016, April 28)

Objective. Mesenchymal stromal cells (MSC) therapy has been suggested in kidney transplantation (KTx). We report on the 1-year follow-up of an open-label phase I trial using MSC at the time of KTx ... [more ▼]

Objective. Mesenchymal stromal cells (MSC) therapy has been suggested in kidney transplantation (KTx). We report on the 1-year follow-up of an open-label phase I trial using MSC at the time of KTx. Methods. On postoperative day 3 (D3), third-party MSC (~2.0x106/kg) were administered to 7 non-immunized first-transplant recipients from deceased donors, under standard immunosuppression (Basiliximab, Tacrolimus, MMF and steroids). No HLA matching was required for MSC donors. In parallel, 7 comparable KTx recipients were included as controls. Written informed consent was obtained from all participants. Results. No hemodynamic or immune-allergic side-effect was noted at the time of MSC injection. Still, 1 patient with a history of ischemic heart disease had a NSTEMI ~3h after MSC infusion. Four MSC patients presented with CMV reactivation within 165 ± 96 days post KTx, whereas 3 controls had positive polyoma-BK viremia within 92 ± 4d post KTx. Three MSC patients were affected by pneumonia within 269 ± 98d post KTx, whereas 3 controls had urinary infection within 48 ± 43d post KTx. No MSC engraftment syndrome was observed. At D14, eGFR in MSC and control groups was 47.1 ± 6.8 and 39.7 ± 5.9 ml/min, respectively (p, 0.05). At 1 year, eGFR in MSC and control groups was 43.1 ± 17.8 and 53.9 ± 13.4 ml/min, respectively (p, 0.25). At 3-month protocol biopsy, no rejection was evidenced in MSC or control patients. Later on, 1 acute rejection was diagnosed at D330 in 1 MSC patient. No biopsy-proven AR was noted in controls. Three patients developed anti-HLA antibodies against MSC (n=1) or shared kidney/MSC (n=2) mismatches. Conclusions. MSC infusion was safe in all patients except one. Incidence of opportunist and non-opportunist infections was similar in both MSC and control groups. No MSC engraftment syndrome was documented. No difference in eGFR was found at 1 year post KTx. Putative immunization against MSC was observed in 3 patients. [less ▲]

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See detailDiscontinuity lines in superconducting films with predefined edge defects
Brisbois, Jérémy ULg

Conference (2016, April 27)

We present a thorough investigation by magneto-optical imaging of the magnetic flux penetration in Nb thin films with lithographically defined border indentations. We demonstrate that discontinuity lines ... [more ▼]

We present a thorough investigation by magneto-optical imaging of the magnetic flux penetration in Nb thin films with lithographically defined border indentations. We demonstrate that discontinuity lines (d-lines), caused by the abrupt bending of current streamlines around the indentations, depart from the expected parabolic trend close to the defect and depend on the shape and size of the indentation as well as on the temperature. These findings are backed up and compared with theoretical results obtained by numerical simulations and analytical calculations highlighting the key role played by demagnetization effects and the creep exponent n. In addition, we show that the presence of nearby indentations and submicrometer random roughness of the sample border can severely modify the flux front topology and dynamics. Strikingly, in contrast to what has been repeatedly predicted in the literature, we do not observe that indentations act as nucleation spots for flux avalanches, but they instead help to release the flux pressure and avoid thermomagnetic instabilities. [less ▲]

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See detailLe diabète et la sélection médicale
PAQUOT, Nicolas ULg

Conference (2016, April 27)

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See detailOikoi and State. A new light on Upper Mesopotamian economic system
Mas, Juliette ULg

Conference (2016, April 27)

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See detailIsolation and characterization of mutants deficient in four steps of the phylloquinone biosynthesis pathway in Chlamydomonas reinhardtii.
Emonds-Alt, Barbara ULg; Remacle, Claire ULg; Cardol, Pierre ULg

Poster (2016, April 26)

In photosystem I (PSI), phylloquinone participates to electron transfer as secondary electron acceptor (A1). The phylloquinone biosynthesis pathway, previously characterized by reverse genetic in ... [more ▼]

In photosystem I (PSI), phylloquinone participates to electron transfer as secondary electron acceptor (A1). The phylloquinone biosynthesis pathway, previously characterized by reverse genetic in Synechocystis sp. PCC 6803, involves 8 enzymatic steps from chorismate [1]. In the green alga Chlamydomonas reinhardtii, characterization of phylloquinone biosynthesis was still partial and only one mutant deficient for MEND was characterized [2]. In the present work, we found MENA-H homologs in C. reinhardtii genomic database. In particular, MENF, MEND, MENC, and MENH catalytic domains are present in a single ORF (named PHYLLO by similarity to gene organisation in Arabidopsis). We then took advantage of the fact that a double reduction of plastoquinone (PQ) in PQH2 occurs in anoxia into the A1 site in the mend mutant, interrupting photosynthetic electron transfer [3], to isolate new phylloquinone-deficient strains. UPLC-MS analysis confirmed the absence of phylloquinone in four news mutants impaired in MENA, MENB, MENC (PHYLLO) and MENE. Despite this loss, men mutants are still able to grow in low light but are high light-sensitive. In low light, the level of active PSII in men mutants is identical to that of the wild-type, but the level of active PSI is reduced by 30-40% as assayed by spectroscopic measurements. This decrease is more pronounced when cells are exposed to high light intensities during 4 hours. The level of active PSI is ~ 10% of wild-type cells and the electron photosynthetic transfer is reduced accordingly. Reorganization of the photosynthetic apparatus following lack of phylloquinone in men mutants is discussed. [less ▲]

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See detailJupiter’s magnetopause: A search for reconnection and wave signatures
Bonfond, Bertrand ULg; Kivelson, Margaret; Khurana, Krishan et al

Conference (2016, April 26)

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See detailIsolation and characterization of mutants deficient in four steps of the phylloquinone biosynthesis pathway in Chlamydomonas reinhardtii.
Emonds-Alt, Barbara ULg; Remacle, Claire ULg; Cardol, Pierre ULg

Poster (2016, April 26)

In photosystem I (PSI), phylloquinone participates to electron transfer as secondary electron acceptor (A1). The phylloquinone biosynthesis pathway, previously characterized by reverse genetic in ... [more ▼]

In photosystem I (PSI), phylloquinone participates to electron transfer as secondary electron acceptor (A1). The phylloquinone biosynthesis pathway, previously characterized by reverse genetic in Synechocystis sp. PCC 6803, involves 8 enzymatic steps from chorismate [1]. In the green alga Chlamydomonas reinhardtii, characterization of phylloquinone biosynthesis was still partial and only one mutant deficient for MEND was characterized [2]. In the present work, we found MENA-H homologs in C. reinhardtii genomic database. In particular, MENF, MEND, MENC, and MENH catalytic domains are present in a single ORF (named PHYLLO by similarity to gene organisation in Arabidopsis). We then took advantage of the fact that a double reduction of plastoquinone (PQ) in PQH2 occurs in anoxia into the A1 site in the mend mutant, interrupting photosynthetic electron transfer [3], to isolate new phylloquinone-deficient strains. UPLC-MS analysis confirmed the absence of phylloquinone in four news mutants impaired in MENA, MENB, MENC (PHYLLO) and MENE. Despite this loss, men mutants are still able to grow in low light but are high light-sensitive. In low light, the level of active PSII in men mutants is identical to that of the wild-type, but the level of active PSI is reduced by 30-40% as assayed by spectroscopic measurements. This decrease is more pronounced when cells are exposed to high light intensities during 4 hours. The level of active PSI is ~ 10% of wild-type cells and the electron photosynthetic transfer is reduced accordingly. Reorganization of the photosynthetic apparatus following lack of phylloquinone in men mutants is discussed. [less ▲]

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See detailThe many aurorae of Jupiter: proxis of the magentospheric dynamics
Bonfond, Bertrand ULg

Conference (2016, April 25)

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See detailValidity of algometry and video assessment to diagnose pain in sheep with knee synovitis
Niessen, J; Nisolle, JF; Hontoir, F et al

Poster (2016, April 23)

Reasons to perform study. To assess lameness in animals, semi-objective scales are used. Video is sometimes used to enable blinding of the clinician. In addition, the assessment of pain is particularly ... [more ▼]

Reasons to perform study. To assess lameness in animals, semi-objective scales are used. Video is sometimes used to enable blinding of the clinician. In addition, the assessment of pain is particularly difficult in animals since they cannot report their feelings. The interpretation of the reactions of the animals can be different between observers. A method to quantify pain is the measure of mechanical nociceptive thresholds (MNT), a method called algometry. Since synovitis is often linked to swelling of periarticular tissues and to synovial fluid effusion, palpation of the joint is also a useful test. The objectives of the current study were to assess in sheep whether (1) video assessment of lameness is in agreement with real observation; (2) algometry of the knee is correlated with lameness evaluation; (3) algometry is correlated with identification of swelling by palpation. Material and methods. The population of sheep enrolled in a controlled trial at the Ovine Research Center of UNamur was used for the current study. Results. There was a moderate inter-rater agreement (value of kappa was 0,41) between the experimenter who evaluated the ewes on site and the one who watched the videos. No significant correlation was identified between lameness scores and algometry. A negative correlation (algometry reactive threshold is lower when palpation score is higher) was identified between palpation scores and MNT (P<0.05). Discussion. Video assessment can be used in research to assess lameness. The experience of the observer must be taken into account. Algometry is not entirely valid since an adaptation or learning process seems to develop in sheep. [less ▲]

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See detailUsing a dynamic vegetation model for future projections of crop yields : application to Belgium in the framework of the VOTES and MASC projects
Jacquemin, Ingrid ULg; Henrot, Alexandra-Jane ULg; Fontaine, Corentin M. et al

Poster (2016, April 22)

Dynamic vegetation models (DVM) were initially designed to describe the dynamics of natural ecosystems as a function of climate and soil, to study the role of the vegetation in the carbon cycle. These ... [more ▼]

Dynamic vegetation models (DVM) were initially designed to describe the dynamics of natural ecosystems as a function of climate and soil, to study the role of the vegetation in the carbon cycle. These models are now directly coupled with climate models in order to evaluate feedbacks between vegetation and climate. But DVM characteristics allow numerous other applications, leading to amelioration of some of their modules (e.g., evaluating sensitivity of the hydrological module to land surface changes) and developments (e.g., coupling with other models like agent-based models), to be used in ecosystem management and land use planning studies. It is in this dynamic context about DVMs that we have adapted the CARAIB (CARbon Assimilation In the Biosphere) model. One of the main improvements is the implementation of a crop module, allowing the assessment of climate change impacts on crop yields. We try to validate this module at different scales: - from the plot level, with the use of eddy-covariance data from agricultural sites in the FLUXNET network, such as Lonzée (Belgium) or other Western European sites (Grignon, Dijkgraaf,. . . ), - to the country level, for which we compare the crop yield calculated by CARAIB to the crop yield statistics for Belgium and for different agricultural regions of the country. Another challenge for the CARAIB DVM was to deal with the landscape dynamics, which is not directly possible due to the lack of consideration of anthropogenic factors in the system. In the framework of the VOTES and the MASC projects, CARAIB is coupled with an agent-based model (ABM), representing the societal component of the system. This coupled module allows the use of climate and socio-economic scenarios, particularly interesting for studies which aim at ensuring a sustainable approach. This module has particularly been exploited in the VOTES project, where the objective was to provide a social, biophysical and economic assessment of the ecosystem services in four municipalities under urban pressure in the center of Belgium. The biophysical valuation was carried out with the coupled module, allowing a quantitative evaluation of key ecosystem services as a function of three climatic and socio-economic scenarios. [less ▲]

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See detailEffect of Ribes nigrum leaf extracts on endothelium-dependent vasorelaxation
Tabart, Jessica; Shini-Kerth, Valérie; PINCEMAIL, Joël ULg et al

Poster (2016, April 22)

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See detailHigh anthocyanins content of commercial blackcurrant juices induced endothelium-dependent relaxation in isolated porcine coronary arteries
Kevers, Claire ULg; Shini-Kerth, Valérie; Tabart, Jessica et al

Poster (2016, April 22)

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See detailGuerrier de Dieu ou mercenaire dangereux et inutile ? Usages de la relation de guerre par l’internonce Bichi comme stratégie de déstabilisation du duc Charles IV de Lorraine (1645-1646).
Regibeau, Julien ULg

Conference (2016, April 22)

Le 22 décembre 1645, l’internonce en poste à Bruxelles, Antonio Bichi, donne l’absolution à Charles IV de Lorraine. La sentence prononcée par l’envoyé pontifical doit mettre fin à plus de trois années de ... [more ▼]

Le 22 décembre 1645, l’internonce en poste à Bruxelles, Antonio Bichi, donne l’absolution à Charles IV de Lorraine. La sentence prononcée par l’envoyé pontifical doit mettre fin à plus de trois années de tensions qui font suite à la bulle d’excommunication fulminée par le pape Urbain VIII à l’encontre du duc. Pour le Saint-Siège l’enjeu diplomatique de ce geste est grand. Charles IV, duc de Lorraine et de Bar, est en effet un membre important du parti des dévots, hostile à Richelieu et à sa politique d’abaissement de la maison d’Autriche. Réfugié aux Pays-Bas espagnols depuis l’occupation de ses États par le cardinal, en 1634, il prend part aux dernières phases de la guerre de Trente Ans en mettant ses troupes au service des Habsbourg, aussi bien en France que dans l’Empire. Or, l’excommunication du duc a peu à peu créé des dissensions au sein du clergé et du gouvernement des Pays-Bas. L’irritation qui règne menacerait même la bonne conduite de la guerre menée contre la France et ses alliés protestants. Si, à première vue, la papauté ne prend pas une part active dans ce conflit, elle veille, à travers ses nonces, aux intérêts catholiques qui sont en jeu. À l’occasion de ma communication, je souhaiterais étudier en détails la politique de l’internonce Bichi durant les mois qui précèdent et qui suivent l’absolution de Charles IV. Je désire, pour ce faire, m’arrêter sur l’une des stratégies que le prélat met en place pour mener le duc à se conformer aux instances du Saint-Siège ; à savoir jeter le discrédit sur l’action militaire de celui-ci. La déconstruction systématique de l’image militaire du duc par l’internonce puise ses arguments dans une rhétorique humaniste, largement diffusée par Machiavel et Guichardin, pour bâtir l’image, à la fois archétypale et ancrée dans le présent de la guerre de Trente Ans, d’un condottiere dangereux et inutile, dont les Habsbourg devraient se prémunir. Prenant place au sein d’un arsenal de ressources variées (maîtrise de l’information, entreprise de désinformation, emploi de différents registres de discours, entretien de réseaux d’intérêts,…), cette stratégie dévoile son efficacité à partir du moment où elle est intériorisée par la Curie romaine et fournit un argument supplémentaire à cette dernière pour faire pression sur le gouverneur-général des Pays-Bas, le marquis de Castel Rodrigo. La représentation propagée par l’internonce peine cependant à masquer l’image, toute aussi efficace, de guerrier de Dieu que Charles IV, héritier des Guises et de l’idéologie de la croisade, convoque et entretient. Il ressort donc de la correspondance de l’internonce une représentation plurielle et ambivalente du duc-soldat ; paradoxe apparent qui reflète bien l’état de tension qui règne alors au sein de la cour de Bruxelles autour de Charles IV et de son excommunication. [less ▲]

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See detailKeratinocyte RabGEF1 maintains skin homeostasis in vivo.
Marichal, Thomas ULg

Conference (2016, April 22)

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See detailSupporting integrated and systemic management of windthrow crises by public decision-makers
Riguelle, Simon ULg; Hebert, Jacques ULg; Lejeune, Philippe ULg et al

Poster (2016, April 21)

This poster presents the development of an integrated framework for systemic management of storm damage risk in Wallonia (Belgium) and how it can be implemented throughout the risk management cycle with ... [more ▼]

This poster presents the development of an integrated framework for systemic management of storm damage risk in Wallonia (Belgium) and how it can be implemented throughout the risk management cycle with user-friendly tools and suitable methodologies. [less ▲]

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See detailAssessing heat tracing experiment data sets for direct forecast of temperature evolution in subsurface models: an example of well and geophysical monitoring data
Hermans, Thomas ULg; Klepikova, Maria; Caers, Jef

Conference (2016, April 21)

Hydrogeological inverse modeling is used for integrating data and calibrating subsurface model parameters. On one hand, deterministic approaches are relatively fast but fail to catch the uncertainty ... [more ▼]

Hydrogeological inverse modeling is used for integrating data and calibrating subsurface model parameters. On one hand, deterministic approaches are relatively fast but fail to catch the uncertainty related to the spatial distribution of model parameters. On the other hand, stochastic inverse modeling is time-consuming and sampling the full high-dimensional parameter space is generally impossible. Even then, the end result is not the inverted model itself, but the forecast built from such models. In this study, we investigate a prediction-focused approach (PFA) in order to derive a direct statistical relationship between data and forecast without explicitly calibrating any models to the data. To derive this relationship, we first sample a limited number of models from the prior distribution using geostatistical methods. For each model, we then apply two forward simulations: the first corresponds to the forward model of the data (past), the second corresponds to the forward model of the forecast (future). The relationship between observed data and forecast is generally highly non-linear, depending on the complexity of the prior distribution and the differences in the two forward operators. In order to derive a useful relationship, we first reduce the dimension of the data and the forecast through principal component analysis (PCA) related techniques in order to keep the most informative part of both sets. Then, we apply canonical correlation analysis (CCA) to establish a linear relationship between data and forecast in the reduced space components. If such a relationship exists, it is possible to directly sample the posterior distribution of the forecast with a multi-Gaussian framework. In this study, we apply this methodology to forecast the evolution with time of the distribution of temperature in a control panel in an alluvial aquifer. We simulate a heat tracing experiment monitored with both well logging probes and electrical resistivity tomography. We show (1) that the proposed method can be used to quantify the uncertainty on the forecast both spatially and temporally and (2) that spatially-distributed data acquired through geophysical methods help to significantly reduce the uncertainty of the posterior. [less ▲]

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See detailAssessment of a design to monitor the influence of crop residue management on the dynamics of soil water content with ERT
Chelin, Marie ULg; Hiel, Marie-Pierre ULg; Hermans, Thomas ULg et al

Poster (2016, April 21)

Choices related to crop residue management affect the soil structure. As a consequence, they may determinethe spatio-temporal dynamics of water content and eventually the crop yields. In order to better ... [more ▼]

Choices related to crop residue management affect the soil structure. As a consequence, they may determinethe spatio-temporal dynamics of water content and eventually the crop yields. In order to better understand the influence of these strategies on hydraulic processes occurring at the plot scale, we opted for the use electrical resistivity tomography (ERT). This approach presents the advantage to limit soil disturbance but is still faced to important challenges when applied in an agricultural field context. Especially changing soil-electrode contact has to be considered, as it can lead to bad quality data, especially for setups with small electrodes and small inter-electrode distance. The objective of this study was to test the efficiency of a high-resolution 3-D field measurement design to properly assess the dynamics of soil water content. ERT measurements were conducted in a Cutanic Siltic Luvisol in Gembloux, Belgium, on two plots of 2m^2 ploughed in Oct 2014 at a depth of 25 cm and sown with maize in April 2015. The plants were removed on one of the plots in order to obtain a bare soil reference. A grid of 98 surface stainless steel electrodes was layed-out on each plot and four sticks supporting each eight stainless steel electrodes were vertically inserted into the soil up to 1.20 m to get more detailed information in depth. The experiments were performed between Jul and Oct 2015, in order to get measurements both in dry and wet periods. For surface and borehole monitoring, a dipole-dipole array configuration including in-line and cross-line measurements was adopted. Normal and reciprocal measurements were performed systematically to assess the data quality: only the datasets with a mean reciprocal error lower than 3% were considered for the data inversion. This contribution will show the first inverted results showing the complexity of experimental design and data analysis for high-resolution, timelapse ERT in field conditions. Based on these results, we will draw conclusions about a minimal data set to be obtained in our upcoming field experiments. [less ▲]

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See detailHigh-resolution climate and land surface interactions modeling over Belgium: current state and decennial scale projections
Jacquemin, Ingrid ULg; Henrot, Alexandra-Jane ULg; Beckers, Veronique et al

Poster (2016, April 21)

The interactions between land surface and climate are complex. Climate changes can affect ecosystem structure and functions, by altering photosynthesis and productivity or inducing thermal and hydric ... [more ▼]

The interactions between land surface and climate are complex. Climate changes can affect ecosystem structure and functions, by altering photosynthesis and productivity or inducing thermal and hydric stresses on plant species. These changes then impact socio-economic systems, through e.g., lower farming or forestry incomes. Ultimately, it can lead to permanent changes in land use structure, especially when associated with other non-climatic factors, such as urbanization pressure. These interactions and changes have feedbacks on the climate systems, in terms of changing: (1) surface properties (albedo, roughness, evapotranspiration, etc.) and (2) greenhouse gas emissions (mainly CO2, CH4, N2O). In the framework of the MASC project (« Modelling and Assessing Surface Change impacts on Belgian and Western European climate »), we aim at improving regional climate model projections at the decennial scale over Belgium and Western Europe by combining high-resolution models of climate, land surface dynamics and socio-economic processes. The land surface dynamics (LSD) module is composed of a dynamic vegetation model (CARAIB) calculating the productivity and growth of natural and managed vegetation, and an agent-based model (CRAFTY), determining the shifts in land use and land cover. This up-scaled LSD module is made consistent with the surface scheme of the regional climate model (RCM: ALARO) to allow simulations of the RCM with a fully dynamic land surface for the recent past and the period 2000-2030. In this contribution, we analyze the results of the first simulations performed with the CARAIB dynamic vegetation model over Belgium at a resolution of 1km. This analysis is performed at the species level, using a set of 17 species for natural vegetation (trees and grasses) and 10 crops, especially designed to represent the Belgian vegetation. The CARAIB model is forced with surface atmospheric variables derived from the monthly global CRU climatology or ALARO outputs (from a 4 km resolution simulation) for the recent past and the decennial projections. Evidently, these simulations lead to a first analysis of the impact of climate change on carbon stocks (e.g., biomass, soil carbon) and fluxes (e.g., gross and net primary productivities (GPP and NPP) and net ecosystem production (NEP)). The surface scheme is based on two land use/land cover databases, ECOPLAN for the Flemish region and, for the Walloon region, the COS-Wallonia database and the Belgian agricultural statistics for agricultural land. Land use and land cover are fixed through time (reference year: 2007) in these simulations, but a first attempt of coupling between CARAIB and CRAFTY will be made to establish dynamic land use change scenarios for the next decades. A simulation with variable land use would allow an analysis of land use change impacts not only on crop yields and the land carbon budget, but also on climate relevant parameters, such as surface albedo, roughness length and evapotranspiration towards a coupling with the RCM. [less ▲]

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See detailOccurrence, fate and risk assessment of personal care products in river-groundwater interface
Jurado Elices, Anna ULg; Serra-Roig, M. Pau; Diaz-Cruz, M. Silvia et al

Conference (2016, April 21)

This work presents the occurrence and fate of selected personal care products (PCPs) in the urban river-groundwater interface. To this end, urban groundwater and river samples were collected in Sant Adrià ... [more ▼]

This work presents the occurrence and fate of selected personal care products (PCPs) in the urban river-groundwater interface. To this end, urban groundwater and river samples were collected in Sant Adrià del Besòs (NE of Spain) and a total of 16 PCPs were analyzed including benzophenone derivatives, camphor derivatives, p-aminobenzoic acid derivatives, triazoles and parabens in three different campaigns (from May 2010 to July 2014). These compounds reach the aquifer through the recharge of River Besòs that receives large amounts of effluents from waste water treatment plants. Results shown that most of compounds were not or barely detected (maximum concentrations around 30 ng/L) in groundwater samples during the different sampling campaigns. Only two triazoles, named as benzotriazole (BZT) and methyl benzotriazol (MeBZT) were found at high concentrations in groundwater samples (maximum concentration around 2000 ng/L). The fate of PCPs in the aquifer was assessed using mixing analysis considering the temporal variability of the River Besòs. Overall, measured groundwater concentrations were significantly much lower than those estimated by the mixing of the river water. This observation suggested that most of the PCPs are naturally removed when river water infiltrates the aquifer. However, some compounds were more persistent in the aquifer. These compounds were in descending order: the triazoles MeBZT and BZT followed by the camphor derivative 4MBC. The measured concentrations allowed us to assess the environmental risk posed by the selected UV-Fs (e.g. benzophenone derivatives) in the river-groundwater samples. Hazard Quotients (HQs) for diferent aquatic species were calculated in order to characterise the ecotoxicity potential of the studied compounds in the river-groundwater interface. HQ values will be presented and discussed in the presentation. [less ▲]

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Peer Reviewed
See detailHeart failure assessment with a multiscale model
Negroni, Jorge; Cabrera-Fischer, Edmundo; Kosta, Sarah ULg et al

Poster (2016, April 21)

Many cardiac diseases lead to heart failure (HF) causing increasing morbidity and mortality worldwide. Several alterations at the myocyte level have been identified, but their specific influence on ... [more ▼]

Many cardiac diseases lead to heart failure (HF) causing increasing morbidity and mortality worldwide. Several alterations at the myocyte level have been identified, but their specific influence on contractile and hemodynamic impairment is not yet clear. Mathematical modeling is a tool to address this issue enabling the analysis of individual myocyte changes on the overall circulatory response. Some myocyte models have been able to reproduce the impact of HF on experimentally detected myocyte components (1), but their integration into a ventricular model forming part of a multiscale circulatory approach has not been fully undertaken. Thus, the aim of this study is to compare the experimental hemodynamic and regional contractile response to acute HF versus a multiscale model based on a human myocyte representation. The experimentally-validated multiscale model shows adequate coupling between myocyte-derived left ventricular chamber and circulatory properties , and would be useful to predict the contractile and hemodynamic response to HF changes in myocyte variables. [less ▲]

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See detailTime lapse imaging of water content with geoelectrical methods: on the interest of working with absolute water content data
Dumont, Gaël ULg; Pilawski, Tamara ULg; Robert, Tanguy et al

Poster (2016, April 21)

The electrical resistivity tomography is a suitable method to estimate the water content of a waste material and detect changes in water content. Various ERT profiles, both static data and time-lapse ... [more ▼]

The electrical resistivity tomography is a suitable method to estimate the water content of a waste material and detect changes in water content. Various ERT profiles, both static data and time-lapse, where acquired on a landfill during the Minerve project. In the literature, the relative change of resistivity ( Delta rho/rho ) is generally computed. For saline or heat tracer tests in the saturated zone, the Delta rho/rho can be easily translated into pore water conductivity or underground temperature changes (provided that the initial salinity or temperature condition is homogeneous over the ERT panel extension). For water content changes in the vadose zone resulting of an infiltration event or injection experiment, many authors also work with the Delta rho/rho or relative changes of water content Delta theta /theta (linked to the change of resistivity through one single parameter: the Archie’s law exponent “m”). This parameter is not influenced by the underground temperature and pore fluid conductivity ( rho_w) condition but is influenced by the initial water content distribution. Therefore, you never know if the loss of / signal is representative of the limit of the infiltration front or more humid initial condition. Another approach for the understanding of the infiltration process is the assessment of the absolute change of water content ( Delta theta ). This requires the direct computation of the water content of the waste from the resistivity data. For that purpose, we used petrophysical laws calibrated with laboratory experiments and our knowledge of the in situ temperature and pore fluid conductivity parameters. Then, we investigated water content changes in the waste material after a rainfall event ( Delta theta = Delta theta /theta * theta ). This new observation is really representatives of the quantity of water infiltrated in the waste material. However, the uncertainty in the pore fluid conductivity value may influence the computed water changes ( Delta theta =k*m*(rho_w)^1/2 ; where “m” is the Archie’s law exponent). Using these two complementary approaches, we analyzed the effect a major rainfall (20-30 mm in 2 hours) that occurred on the test site, characterized by a vegetalized and relatively dry zone and a devegatelized and humid zone. We intended to prove that most of the information contained in the Delta theta /theta distribution is the initial water content distribution in the ground.Water addition in dry zones resulting in large relative changes. The computation of the Delta theta is necessary to demonstrate preferential infiltration through the capping in a restricted zone of the vegetalized area. [less ▲]

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See detailSources pour l’étude des transferts de cultes en Grèce antique
Palamidis, Alaya ULg

Conference (2016, April 20)

A couple of Greek inscriptions show that it was possible to transfer a cult, that is to no longer honour a deity in their original sanctuary, but in a new one founded on this occasion at a different ... [more ▼]

A couple of Greek inscriptions show that it was possible to transfer a cult, that is to no longer honour a deity in their original sanctuary, but in a new one founded on this occasion at a different location. However, they provide few elements to study this phenomenon. The contribution of literary sources is also very limited. Thus, the 1st century A.D. author Strabo mentions four cases of cult transfers, which, however, prove not to correspond to historical events. We should therefore turn to archaeological sources, and especially to the negative evidence: the absence of archaeological material testifying to the frequentation of a sanctuary while the cult of the deity is still attested by other sources provides the best clue to such transfers. On the contrary, there is positive evidence for the relocation of temples, which were entirely taken down and reconstructed elsewhere — the so-called «Wandering temples» — but the reuse of building materials does not imply the transfer of the cult. Further indications that a cult was transferred include coins or even the orientation of temples. [less ▲]

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See detailVers des systèmes d’information archéologique : maquette virtuelle et nuages de points intelligents
Billen, Roland ULg; Van Ruymbeke, Muriel ULg; Pfeiffer, Michelle et al

Conference (2016, April 20)

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See detailThe last millenia sedimentary record of Lago Esponja from Northern Chilean Patagonia
Fagel, Nathalie ULg; Alvarez, Denisse; Araneda, Alberto et al

Poster (2016, April 20)

We evaluate the climate and environmental variability of Northern Chilean Patagonia during the Last Millennia, using a multi-proxy analysis of a sediment core from Lago Esponja (45°09’S, 72°08’W). The ... [more ▼]

We evaluate the climate and environmental variability of Northern Chilean Patagonia during the Last Millennia, using a multi-proxy analysis of a sediment core from Lago Esponja (45°09’S, 72°08’W). The lake is located in the region of Aysen del General Carlos Ibanez del Campo, in NW Patagonia. The study focuses on a multiproxy analysis of sedimentary records. The longest core (150 cm long) was collected in 2014 at 40 m depth. The sediment, which is composed of light brown organic-rich clayey silt, was analyzed for sedimentology (grain size, magnetic susceptibility organic matter and biogenic silica content), mineralogy (X-ray diffraction) and geochemistry (elemental and isotopic analyses of C and N, XRF core-scaner at 1 mm resolution). The radiocarbon ages, measured on 3 macro-remains, demonstrate that the core covers the last 6.700 years. The sedimentation rate ranges between 0.1 mm/yr in the lower section (100-150 cm) and 0.4 mm/yr in the upper meter. Visual descriptions and Scopix radiographies show that the sediment record is finely laminated except a massive decimetric coarser and darker layer corresponding to a tephra (estimated age 700AD±50). Magnetic susceptibility (confirmed by scopix radiographies) highlights the presence of 8 additional millimetric tephra layers. The biogenic silica content of the sediment is low (mean 5%). Diatom assemblage is dominated by benthic and acidophilous species, with high saprobic values. None marked changes were observed regarding the dynamic of the lake. The high organic matter content (mean 15%) and its high C/N ratio (12.7) throughout the core indicate inputs of allochtonous and terrestrial organic matter. Such parameters present high sediment variability also marked by changes in the chemical composition. The laminations reflect changes in the allochtonous sedimentary inputs, with high terrestrial inputs during wetter conditions in relation with the Westerlies. The sedimentary records of Lago Esponja will be compared with Eastern lacustrine record from the same latitude in order to confirm the climate-driven record. [less ▲]

Detailed reference viewed: 18 (5 ULg)
See detailCyclic and oligo-carbonates by organocatalytic coupling of CO2 with epoxides or oxetanes
Alves, Margot ULg; Grignard, Bruno ULg; Boyaval, Amélie ULg et al

Conference (2016, April 20)

Valorising CO2 as a renewable C1 feedstock for producing added value building blocks is the scope of many academic and industrial researches. Carbon dioxide is a thermodynamically and kinetically stable ... [more ▼]

Valorising CO2 as a renewable C1 feedstock for producing added value building blocks is the scope of many academic and industrial researches. Carbon dioxide is a thermodynamically and kinetically stable molecule that can be converted into five and six membered cyclic carbonates by coupling with epoxides or oxetanes, respectively, using appropriate catalysts. Although transition metal catalysts are efficient under atmospheric pressure and ambient temperature, most of them are poorly selective, sensitive to hydrolysis and/or oxidation and/or toxic whereas less/non-toxic and eco-friendly organocatalysts such as ionic liquids and halide salts are generally only efficient at very high temperature and pressure favouring their thermal degradation. To overcome these limitations, we developed a new highly efficient bicomponent homogeneous organocatalyst composed of an ammonium salt as the catalyst and fluorinated single or double hydrogen bond donor activators. Through online FTIR kinetic studies, we demonstrated that this new organocatalyst showed unexpected catalytic activity for the fast and selective addition of CO2 onto epoxides under solvent-free and mild experimental conditions. The use of this dual catalyst was then extended to the coupling of CO2 with less reactive oxetanes to produce hydroxyl telechelic oligocarbonates. In the first part of this talk, based on kinetics of reactions followed by online FTIR under pressure, we will describe the reaction conditions required for the organocatalytic coupling of CO2 with epoxides and oxetanes. In the second part, the mechanism of the reaction will be approached and discussed based on DFT calculations. Finally, we will compare and discuss the efficiency of various organocatalytic systems for this type of reaction. [less ▲]

Detailed reference viewed: 29 (3 ULg)
See detailVolunteering Citizens in Nuclear Risk Governance: Citizen Science after Fukushima
Van Oudheusden, Michiel ULg; Turcanu, Catrinel; Yoshizawa, Go et al

Conference (2016, April 20)

Citizen science (CS) is a form of science developed and enacted by citizens, typically with citizen volunteers collecting and/or analyzing various kinds of data. Whereas common forms of CS like bird ... [more ▼]

Citizen science (CS) is a form of science developed and enacted by citizens, typically with citizen volunteers collecting and/or analyzing various kinds of data. Whereas common forms of CS like bird counting and amateur astronomy generally elicit interest and approval on behalf of scientists, decision makers, and publics at large, CS in the nuclear field is far more contentious. This is due to the controversial nature of nuclear science and technology, as evidenced by public disputes about nuclear energy, nuclear waste management, and nuclear accidents, among others. Starting from these observations, this paper probes the risky, disputed character of CS in nuclear emergency and post-accident situations. It specifically looks at CS in Japan after the 2011 Fukushima Daiichi nuclear disaster, where citizens in affected areas monitor radioactivity in the environment and communicate about health and environmental risks with one another (e.g. Citizens’ Radioactivity Monitoring Project). In these processes, citizen scientists voice ardent criticism of government, industry, and academia, as these institutes are seen to deliberately spread biased information to sustain an illusion of control (http://blog.safecast.org). By taking science and technology into their own hands, they challenge conventional notions of citizen engagement, science, and avocation/volunteerism. The paper draws on the notions of contentious politics and issue politics (e.g. Marres 2005) to highlight the issue-driven, adversarial and untamed character of post-Fukushima CS in the nuclear field. It is argued that these notions better capture what CS after Fukushima amounts to, as conventional representations (e.g. volunteer sensing, “citizens as sensors,” public participation in scientific research) downplay scientific uncertainties and power asymmetries between citizens and authorities, and do not account for how “Fukushima” is reconfiguring scientific citizenship in novel ways. [less ▲]

Detailed reference viewed: 37 (3 ULg)
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See detailImpact of tillage on CO2 and N2O efflux in an agricultural crop
Lognoul, Margaux ULg; Theodorakopoulos, Nicolas ULg; Hiel, Marie-Pierre ULg et al

Poster (2016, April 20)

CO2 and N2O fluxes exchanged by a maize crop were measured from June to Octboer 2015 using a homemade automated system of dynamic closed chambers. We studied the impact of tillage (reduced and ... [more ▼]

CO2 and N2O fluxes exchanged by a maize crop were measured from June to Octboer 2015 using a homemade automated system of dynamic closed chambers. We studied the impact of tillage (reduced and conventional) on greenhouse gas emissions and nitrous oxide flux dynamics. [less ▲]

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See detailHeat tracer test in an alluvial aquifer: field experiment and inverse modelling
Klepikova, Maria; Wildemeersch, Samuel; Jamin, Pierre ULg et al

Poster (2016, April 20)

Using heat as an active tracer for aquifer characterization is a topic of increasing interest. In this study, we investigate the potential of using heat tracer tests for characterization of a shallow ... [more ▼]

Using heat as an active tracer for aquifer characterization is a topic of increasing interest. In this study, we investigate the potential of using heat tracer tests for characterization of a shallow alluvial aquifer. A thermal tracer test was conducted in the alluvial aquifer of the Meuse River, Belgium. The tracing experiment consisted in simultaneously injecting heated water and a dye tracer in a piezometer and monitoring the evolution of groundwater temperature and tracer concentration in the recovery well and in monitoring wells. To get insights in the 3D characteristics of the heat transport mechanisms, temperature data from a large number of observation wells distributed throughout the field site (space-filling arrangement) were used. Temperature breakthrough curves in observation wells are contrasted with what would be expected in an ideal layered aquifer. They reveal strongly unequal lateral and vertical components of the transport mechanisms. The observed complex behavior of the heat plume was explained by the groundwater flow gradient on the site and heterogeneity of hydraulic conductivity field. Moreover, due to high injection temperatures during the field experiment a temperature-induced fluid density effect on heat transport occurred. By using a flow and heat transport numerical model with variable density coupled with the pilot point inverse approach, main preferential flow paths were delineated. [less ▲]

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See detailData-Interpolating Variational Analysis (DIVA) software: recent development and application
Watelet, Sylvain ULg; Back, Örjan; Barth, Alexander ULg et al

Poster (2016, April 20)

Detailed reference viewed: 15 (2 ULg)
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See detailMines as lower reservoir of an UPSH (Underground Pumped Storage Hydroelectricity): groundwater impacts and feasibility
Bodeux, Sarah ULg; Pujades, Estanislao ULg; Orban, Philippe ULg et al

Poster (2016, April 20)

The energy framework is currently characterized by an expanding use of renewable sources. However, their inter- mittence could not afford a stable production according to the energy demand. Pumped Storage ... [more ▼]

The energy framework is currently characterized by an expanding use of renewable sources. However, their inter- mittence could not afford a stable production according to the energy demand. Pumped Storage Hydroelectricity (PSH) is an efficient possibility to store and release electricity according to the demand needs. Because of the topographic and environmental constraints of classical PSH, new potential suitable sites are rare in countries whose topography is weak or with a high population density. Nevertheless, an innovative alternative is to construct Underground Pumped Storage Hydroelectricity (UPSH) plants by using old underground mine works as lower reservoir. In that configuration, large amount of pumped or injected water in the underground cavities would impact the groundwater system. A representative UPSH facility is used to numerically determine the interactions with surrounding aquifers Different scenarios with varying parameters (hydrogeological and lower reservoir char- acteristics, boundaries conditions and pumping/injection time-sequence) are computed. Analysis of the computed piezometric heads around the reservoir allows assessing the magnitude of aquifer response and the required time to achieve a mean pseudo-steady state under cyclic solicitations. The efficiency of the plant is also evaluated taking the leakage into the cavity into account. Combining these two outcomes, some criterions are identified to assess the feasibility of this type of projects within potential old mine sites from a hydrogeological point of view. [less ▲]

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See detailUsing NDACC column measurements of carbonyl sulfide to estimate its sources and sinks
Wang; Marshall, J; Palm, M et al

in Geophysical Research Abstracts (2016, April 19), 18

Detailed reference viewed: 16 (3 ULg)
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See detailA Study Of Dry Stiction Phenomenon In MEMS Using A Computational Stochastic Multi-scale Methodology
Hoang Truong, Vinh ULg; Wu, Ling ULg; Paquay, Stéphane et al

in EuroSimE 2016 in Montpellier (2016, April 19)

This work studies the uncertainties of the adhesive contact problems for reduced size structures, e.g. the stiction failure of microelectromechanical systems (MEMS). In MEMS, because of the large surface ... [more ▼]

This work studies the uncertainties of the adhesive contact problems for reduced size structures, e.g. the stiction failure of microelectromechanical systems (MEMS). In MEMS, because of the large surface to volume ratio, the surfaces forces, such as van der Waals forces and capillary forces, are dominant in comparison with the body forces. As these force magnitudes strongly depend on the contact distance, when the two contacting surfaces are rough, the contact distances vary, and the physical contact areas are limited at the highest asperities of the contacting surfaces. Therefore, the adhesive contact forces between two rough surfaces can suffer from a scatter, and the involved structural behaviors can be indeterministic. To numerically predict the probability behaviors of structures involving adhesion in dry environments, in this paper, a computational stochastic model-based multi-scale method developed by the authors is applied. The effects of van der Waals is studied and compared with experimental data as well as with the effects of capillary forces. [less ▲]

Detailed reference viewed: 44 (22 ULg)
See detailDrought-related vulnerability and risk assessment of groundwater in Belgium: estimation of the groundwater recharge and crop yield vulnerability with the B-CGMS
Jacquemin, Ingrid ULg; Verbeiren, Boud; Vanderhaegen, Sven et al

Poster (2016, April 19)

Due to common belief that regions under temperate climate are not affected by (meteorological and groundwater) drought, these events and their impacts remain poorly studied: in the GroWaDRISK, we propose ... [more ▼]

Due to common belief that regions under temperate climate are not affected by (meteorological and groundwater) drought, these events and their impacts remain poorly studied: in the GroWaDRISK, we propose to take stock of this question. We aim at providing a better understanding of the influencing factors (land use and land cover changes, water demand and climate) and the drought-related impacts on the environment, water supply and agriculture. The study area is located in the North-East of Belgium, corresponding approximatively to the Dijle and Demer catchments. To establish an overview of the groundwater situation, we assess the system input: the recharge. To achieve this goal, two models, B-CGMS and WetSpass are used to evaluate the recharge, respectively, over agricultural land and over the remaining areas, as a function of climate and for various land uses and land covers. B-CGMS, which is an adapted version for Belgium of the European Crop Growth Monitoring System, is used for assessing water recharge at a daily timestep and under different agricultural lands: arable land (winter wheat, maize...), orchards, horticulture and floriculture and for grassland. B-CGMS is designed to foresee crop yield and obviously it studies the impact of drought on crop yield and raises issues for the potential need of irrigation. For both yields and water requirements, the model proposes a potential mode, driven by temperature and solar radiation, and a water-limited mode for which water availability can limit crop growth. By this way, we can identify where and when water consumption and yield are not optimal, in addition to the Crop Water Stress Index. This index is calculated for a given crop, as the number of days affected by water stress during the growth sensitive period. Both recharge and crop yield are assessed for the current situation (1980 – 2012), taking into account the changing land use/land cover, in terms of areas and localization of the agricultural land and where the proportion of the different crops had considerably evolved through time (e.g., increase of grain maize and potatoes while winter cereals decrease). The preliminary results of the recharge lead to an average value in the area showing a significant negative trend, in both simulations with fixed (base = 1980) and changing land cover. In the same time, we could observe an increasing number of water stress periods, especially for maize, one of the main crops in the area. Finally, a preliminary test will be presented for the horizon 2040, for which we use meteorological time series (for high and low hydrologic impacts) given by the CCI-HYDR Perturbation Tool (Ntegeka V. and Willems P., 2009). This preliminary test aims to (1) evaluate the amplitude of the potential recharge deficit and, (2) especially, to define vulnerability zones, affected by frequent water stress, in connection with irrigation needs which could possibly increase the groundwater extraction. [less ▲]

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See detailDecrease in hydroclimatic conditions generating floods in the southeast of Belgium over the last 50 years
Wyard, Coraline ULg; Fettweis, Xavier ULg

Conference (2016, April 19)

As a consequence of climate change, several studies concluded that winter flood occurrence could increase in the future in many rivers of northern and western Europe in response to an increase in extreme ... [more ▼]

As a consequence of climate change, several studies concluded that winter flood occurrence could increase in the future in many rivers of northern and western Europe in response to an increase in extreme precipitation events. This study aims to determine if trends in extreme hydroclimatic events generating floods can already be detected over the last century. In particular, we focus on the Ourthe River (southeast of Belgium) which is one of the main tributaries of the Meuse River with a catchment area of 3500 km² . In this river, most of the floods occur during winter and about 50% of them are due to rainfall events associated with the melting of the snow which covers the Ardennes during winter. In this study, hydroclimatic conditions favourable to floods were reconstructed over the period 1959-2010 using the regional climate model MAR (“Modèle Atmosphérique Régional”) forced by the following reanalyses: the ERA-20C, the ERA-Interim and the NCEP/NCAR-v1. The use of the MAR model allows to compute precipitation, snow depth and run-off resulting from precipitation events and snow melting in any part of the Ourthe river catchment area. Therefore, extreme hydroclimatic events, namely extreme run-off events, which could potentially generate floods, can be reconstructed using the MAR model. As validation, the MAR results were compared to weather station-based data. A trend analysis was then performed in order to study the evolution of conditions favourable to flooding in the Ourthe River catchment. The results show that the MAR model allows the detection of about 90% of the hydroclimatic conditions which effectively generated observed floods in the Ourthe River over the period 1974-2010. Whatever the reanalysis used to force the MAR model, the conditions favourable to floods due to snowpack melting combined with rainfall events present a significant negative trend over the last 50 years as a result of a decrease in snow accumulation. However, regarding the conditions favourable to floods due to rainfall events alone, the signal of the trend depends on the reanalysis used to force the model. [less ▲]

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See detailA Raster SOLAP for the Visualization of Crime Data Fields
Kasprzyk, Jean-Paul ULg; Donnay, Jean-Paul ULg

in Rückemann, Claus-Peter (Ed.) GEOProcessing 2016 (2016, April 19)

In order to effectively extract synthetic information from large spatial data sets, Spatial OnLine Analytical Processing (SOLAP) combines Geographic Information Systems (GIS) with Business Intelligence ... [more ▼]

In order to effectively extract synthetic information from large spatial data sets, Spatial OnLine Analytical Processing (SOLAP) combines Geographic Information Systems (GIS) with Business Intelligence (BI) to query data warehouses through interactive vector maps. On the other hand, crime strategical analysis is usually based on raster maps computed by Kernel Density Estimation (KDE), then independent of any artificial boundary. This paper introduces an alternative vision of SOLAP which uses the raster model (instead of the vector one) in order to integrate crime data fields computed by KDE. It allows a continuous visualization of spatial data which, until now, has not been compatible with other SOLAP tools. The original geo-model is validated by a prototype adapted to the police needs. [less ▲]

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See detailIs Ambrosia artemisiifolia L. able to expand its invaded range northward in Western Europe?
Ortmans, William ULg; Mahy, Grégory ULg; Monty, Arnaud ULg

Poster (2016, April 19)

Ambrosia artemisiifolia L. (common ragweed, Asteraceae) is an invasive weed causing a health crisis in Europe, due to its highly allergenic pollen. In Western Europe the invaded range covers most of ... [more ▼]

Ambrosia artemisiifolia L. (common ragweed, Asteraceae) is an invasive weed causing a health crisis in Europe, due to its highly allergenic pollen. In Western Europe the invaded range covers most of central and southern France, and northern Italy. Northwards beyond the edge of this range, occurrence of casual population have been described for years, but these populations do not appear to become invasive, and the species does not seem to spread. This situation raises the following question: Has the invaded range reached a limit or will the species continue its invasion northwards? To answer this question, we followed two complementary approaches. First we set up an experimental garden in Belgium, 250 km north to the current invaded range, to see if the local climate allows the completion of the species reproduction cycle. Second, we performed an in situ measurement campaign in 12 population located beyond the edge, within the range but near the margin, and in the center of the invaded range. The aim of this campaign was to test whether the species had reduced plant performance towards range margins. The results showed that the species is able to establish populations with high growth rates in Belgium. Furthermore, the species expressed similar performance across the considered areas, even beyond the current invasion front. No evidence of processes constraining the invasion was found, which suggests a great potential for invasion north to the current invaded range. In this uncertain situation, awareness actions should be considered in the northern countries. [less ▲]

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See detailReactive gases in the chemistry climate model ECHAM6-HAMMOZ
Schultz, Martin; Franco, Bruno ULg; Kaffashzadeh, Najmeh et al

Poster (2016, April 18)

The recently developed global chemistry climate model ECHAM6-HAMMOZ contains comprehensive and detailed schemes for tropospheric aerosol (HAM) and reactive gases chemistry (MOZ). The Jülich Atmospheric ... [more ▼]

The recently developed global chemistry climate model ECHAM6-HAMMOZ contains comprehensive and detailed schemes for tropospheric aerosol (HAM) and reactive gases chemistry (MOZ). The Jülich Atmospheric (chemical) Mechanism (JAM002) consists of more than 300 species and 650 reactions, including relatively detailed degradation pathways for various volatile organic compounds in the troposphere and stratosphere. State-of-the-art parameterisations for chemical and physical processes are included. Here we present evaluation results from a multi-year simulation of the present-day atmospheric composition. [less ▲]

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See detailAre BVOC exchanges in agricultural ecosystems overestimated? Insights from fluxes measured in a maize field over a whole growing season
Bachy, Aurélie ULg; Aubinet, Marc ULg; Schoon, Niels et al

Conference (2016, April 18)

This oral communication aims to present the main outputs of the BVOC (Biogenic Volatile Organic Compounds) flux measurement campaign performed on a maize field in Belgium. It begins by highligthing the ... [more ▼]

This oral communication aims to present the main outputs of the BVOC (Biogenic Volatile Organic Compounds) flux measurement campaign performed on a maize field in Belgium. It begins by highligthing the interest of investigating BVOC exchanges on maize; then measurement techniques are briefly presented. The second half of the communication aims to present and discuss the main outputs of this measurement campaign (similar BVOC composition, lower exchange rate than other maize and cropland/grassland studies, significant importance of soil in ecosystem exchanges, strong differences between exchanges rates observed in this study and those used by up-scaling models). [less ▲]

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See detailInter-system biases estimation in multi-GNSS relative positioning with GPS and Galileo
Deprez, Cécile ULg; Warnant, René ULg

Conference (2016, April 18)

The recent increase in the number of Global Navigation Satellite Systems (GNSS) opens new perspectives in the field of high precision positioning. Particularly, the European Galileo program has ... [more ▼]

The recent increase in the number of Global Navigation Satellite Systems (GNSS) opens new perspectives in the field of high precision positioning. Particularly, the European Galileo program has experienced major progress in 2015 with the launch of 6 satellites belonging to the new Full Operational Capability (FOC) generation. Associated with the ongoing GPS modernization, many more frequencies and satellites are now available. Therefore, multi-GNSS relative positioning based on GPS and Galileo overlapping frequencies should entail better accuracy and reliability in position estimations. However, the differences between satellite systems induce inter-system biases (ISBs) inside the multi-GNSS equations of observation. Once these biases estimated and removed from the model, a solution involving a unique pivot satellite for the two considered constellations can be obtained. Such an approach implies that the addition of even one single Galileo satellite to the GPS-only model will strengthen it. The combined use of L1 and L5 from GPS with E1 and E5a from Galileo in zero baseline double differences (ZB DD) based on a unique pivot satellite is employed to resolve ISBs. This model removes all the satelliteand receiver-dependant error sources by differentiating and the zero baseline configuration allows atmospheric and multipath effects elimination. An analysis of the long-term stability of ISBs is conducted on various pairs of receivers over large time spans. The possible influence of temperature variations inside the receivers over ISB values is also investigated. Our study is based on the 5 multi-GNSS receivers (2 Septentrio PolaRx4, 1 Septentrio PolaRxS and 2 Trimble NetR9) installed on the roof of our building in Liege. The estimated ISBs are then used as corrections in the multi-GNSS observation model and the resulting accuracy of multi-GNSS positioning is compared to GPS and Galileo standalone solutions. [less ▲]

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See detailCanopy proximity estimation and impact on long term turbulent fluxes above a heterogeneous forest
Hurdebise, Quentin ULg; Vincke, Caroline; De Ligne, Anne ULg et al

Poster (2016, April 18)

With the development of eddy covariance networks like Fluxnet, ICOS or NEON, long-term data series of carbon dioxide, water vapor and other gas exchanges between terrestrial ecosystems and atmosphere will ... [more ▼]

With the development of eddy covariance networks like Fluxnet, ICOS or NEON, long-term data series of carbon dioxide, water vapor and other gas exchanges between terrestrial ecosystems and atmosphere will become more and more numerous. However, long-term analyses of such exchanges require a good understanding of measurement conditions during the investigated period. Independently of climate drivers, measurements may indeed be influenced by measurement conditions themselves subjected to long-term variability due to vegetation growth or set-up changes. The present research refers to the Vielsalm Terrestrial Observatory (VTO) where fluxes of momentum, carbon dioxide, latent and sensible heat have been continuously measured by eddy covariance during twenty years. VTO is an ICOS site installed in a mixed forest (beech, silver fir, Douglas fir, Norway spruce) in the Belgian Ardennes. A multidisciplinary approach was developed in order to investigate the spatial and temporal evolution of several site characteristics: - displacement height (d) and relative measurement height (z-d) were determined using a spectral approach that compared observed and theoretical cospectra; - turbulence statistics were analyzed in the context of Monin-Obukhov similarity theory; - tree height during the measurement period was obtained by combining tree height inventories, a LIDAR survey and tree growth models; - measurement footprint was determined by using a footprint model. A good agreement was found between the three first approaches. Results show notably that z-d was subjected to both temporal and spatial evolution. Temporal evolution resulted from continuous tree growth as well as from a tower raise, achieved in 2009. Spatial evolution, due to canopy heterogeneity, was also observed. The impacts of these changes on measurements are investigated. In particular, it was shown that they affect measurement footprint, flux spectral corrections and flux quality. All these effects must be taken into consideration in order to disentangle long-term flux evolutions due to climate or phenology from changes resulting from measurement set-up changes. [less ▲]

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See detailSelection of wavelengths for the quantification of nitrogen concentration in winter wheat by multispectral vision
Marlier, Guillaume ULg; Leemans, Vincent ULg; Destain, Marie-France ULg et al

Poster (2016, April 18)

Hand-held sensors (SPAD meter, N-Tester, …) are used for detecting the leaves nitrogen concentration (Nc) on basis of an optical detection of the chlorophyll concentration. These devices are active ... [more ▼]

Hand-held sensors (SPAD meter, N-Tester, …) are used for detecting the leaves nitrogen concentration (Nc) on basis of an optical detection of the chlorophyll concentration. These devices are active sensors: an internal radiation source emits light and transmission through a leaf is measured in the red (650 nm) and in the near-infrared (920 nm) spectral regions. These devices present several drawbacks. The nitrogen concentration is gained by an indirect way through the chlorophyll concentration and the leaves have to be fixed in a defined position for the measurements. These drawbacks could be overcome by an imaging device that measures the canopy reflectance. Hence, the objective of the paper is to analyse the potential of multispectral imaging for detecting nitrogen concentration. The tests were carried out on parcels submitted to nitrogen inputs varying from 0 to 180 kg N.ha-1. Reference Nc measurements were obtained by the Kjeldahl method and a Hydro N-Tester (Yara). The developed imaging system comprised a CMos camera and a set of 22 interference filters ranging from 450 to 950 nm mounted on a wheel steered by a stepper motor. The image acquisition and the motor rotation were controlled by a program written in C++. The crop was imaged vertically at one meter height. The raw images presented 1280*1024 pixels covering an area approximately 0.5*0.4 m and were recorded with a 12 bits luminance resolution. To deal with the natural irradiance variability of the scene, a white reference was used and the integration time was automatically adjusted for each image. The image treatment included the segmentation of Photosynthetically Active Leaves (PAL) by using Bayes theorem and the computation of the mean PAL reflectance after correction of background and illumination fluctuations. Nc was estimated on basis of the 22 filters by Partial Least Square (PLS) method and by four filters selected by Best Subset Selection (BSS). In comparison with the Kjeldahl method, the estimation of Nc by the Hydro N-Tester, the PLS and the BSS (filters 600-80, 950-100, 650-40 and 450-80 nm) gave determination coefficient and standard error respectively equal to of 0.53, 0.29 %; 0.67, 0.21%; 0.56 and 0.25%. This indicated that the full multi-spectral approach gave significantly better Nc estimation than a portable device and suggested that a camera equipped with four filters would give similar results. [less ▲]

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See detailContrasted terrace systems of the lower Moulouya valley as indicator of crustal deformation in NE Morocco
Rhixon, Gilles; Bartz, Melanie; El Ouahabi, Meriam ULg et al

Conference (2016, April 17)

The Moulouya has the largest catchment in Morocco and drains an area which is characterized by active crustal deformation during the Late Cenozoic due to the convergence between the African and Eurasian ... [more ▼]

The Moulouya has the largest catchment in Morocco and drains an area which is characterized by active crustal deformation during the Late Cenozoic due to the convergence between the African and Eurasian plates. As yet, its Pleistocene terrace sequence remains poorly documented. Our study focuses on the lowermost reach of the river in NE Morocco, which drains the Triffa sedimentary basin directly upstream of the estuary. New field observations, measurements and sedimentological data reveal contrasted fluvial environments on either side of a newly identified thrust zone, which disrupts the whole sedimentary basin and is associated with N–S compressive shortening in this region. Long-lasting fluvial aggradation, materialized by ≥37 m-thick stacked fill terraces, and the development of a well-preserved terrace staircase, with (at least) three Pleistocene terrace levels, occur in the footwall and the hanging wall of the thrust, respectively. Same as for the Pleistocene terrace sediments of the middle Moulouya, a recurrent sedimentary pattern, characterized by fining-upward sequences was observed in the studied terrace profiles. Assessing the rates of crustal deformation along this main thrust zone requires age estimations for these Pleistocene terrace deposits of the lower Moulouya on each side of the thrust. Samples for luminescence (OSL/IRSL), electron spin resonance (ESR) and cosmogenic nuclide dating (26Al/10Be, burial dating) were collected in terrace deposits located both in the foot- and hanging walls. Sample preparation and analysis as well as age determination are in progress. The preliminary data mentioned above, soon to be completed by chronological data, agree well with morphometric indicators stating that the whole Moulouya catchment is at disequilibrium state (Barcos et al., 2014). This is confirmed by several knickpoints in its longitudinal profile. Late Cenozoic uplift associated with crustal shortening, which occurred in the lowermost reach of the river, may have both hindered profile rectification of the Moulouya and, at the same time, buffered the effects of long-term base-level changes due to eustatic sea-level variations. [less ▲]

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See detailTowards a better understanding of ephemeral stream morphodynamics during the last 100 ka in the vicinity of the prehistoric site of Ifri n’Ammar (Morocco)
Bartz, Melanie; Rhixon; Khel, Martin et al

Conference (2016, April 17)

Our study focusses on the ephemeral stream deposits of Wadi Selloum to reconstruct the palaeoenvironmental evolution in direct vicinity of the rock shelter Ifri n’Ammar. As one of the oldest settlement ... [more ▼]

Our study focusses on the ephemeral stream deposits of Wadi Selloum to reconstruct the palaeoenvironmental evolution in direct vicinity of the rock shelter Ifri n’Ammar. As one of the oldest settlement sites of anatomically modern humans (AMH) in North Africa, Ifri n’Ammar documents periodical occupations since ~170 ka. Since these discontinuous settlement dynamics may be related to or influenced by landscape changes and climate forcing, our study aims (i) to identify phases of morphodynamic activity and stability in the deposits of Wadi Selloum by using micromorphological (sixteen thin sections), sedimentological (laser diffractometry, loss on ignition, magnetic susceptibility), geochemical ( XRF and Scheibler method) and mineralogical (X-ray diffractometry) proxies. Furthermore, (ii) a robust chronology for the ephemeral stream deposits is established by applying a combination of optically stimulated luminescence (OSL) and post infrared stimulated luminescence (pIRIR290) dating. Additionally, one collected pottery shard was dated by thermoluminescence (TL) dating for an inter method comparison. The application of luminescence dating techniques to Wadi Selloum deposits yielded burial ages between 1.3 ± 0.2 ka and 102 ± 8 ka covering different phases of morphodynamically stable and active phases. Enhanced aggradation is evident between ~100 and 60 ka, ~21 and 14 ka and during the Holocene. Overbank fines are distinguished by high amounts of allochthonous minerals such as quartz, muscovite, K-feldspar and plagioclase which give rise to higher eolian activity. This leads to the suggestion that morphodynamical activity was dominant during more arid phases. Landscape stability was observed in form of one palaeosol (2B-2C-sequence; OIS 3) and a recent soil (Ap/Ah-Bw-Bk-BC-C-sequence; after LGM), both attributed to the Calcisol group. Pedogenenesis is evident in thin sections by well-developed subangular blocky peds. The main soil forming process is secondary carbonate precipitation in subsoil horizons, supported by pedofeatures such as calcite infillings and hypocoatings. Holocene deposits (6.4 ± 4 to 1.3 ± 0.2 ka) seem to be affected by short-termed changes between landscape stability and hydromorphic activity due to strong variations in its mineralogical and geochemical characteristics. This is supported by a homogeneous and sterile stratigraphy, as well as an insignificant differentiation in soil horizons with only weakly developed pedofeatures. The sediment characteristics present a weak Ap-C-sequence of a calcaric Fluvisol. After ~1.3 ± 0.2 ka fluvial discharge was reduced and incision took place in the Wadi Selloum. Our study provides first insights in the palaeoenvironment around Ifri n’Ammar during the last glacial interglacial cycle and gives first suggestions about climatic conditions during the time of human occupation in Ifri n’Ammar. [less ▲]

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See detailChemical and mineralogical proxies of erosion episodes in the dried lake sediments (Amik Lake, Southern Turkey): paleoenvironmental implications
El Ouahabi, Meriam ULg; Hubert, Aurelia ULg; Lebeau, Héléne et al

Poster (2016, April 17)

The Amik Basin in the Eastern Mediterranean region has been continuously occupied since 6000-7000 BC. The landscape has sustained with highly variable anthropic pressure culminating during the Late Roman ... [more ▼]

The Amik Basin in the Eastern Mediterranean region has been continuously occupied since 6000-7000 BC. The landscape has sustained with highly variable anthropic pressure culminating during the Late Roman Period when the Antioch city reached its golden age. The basin also sustained a high seismic activity (M≥7) as it is a releasing step-over along the Dead Sea Fault. The study focuses on the sedimentary record of the Amik Lake occupying the central part of the Basin. Our objective is to constrain major paleo-environmental changes in the area over the last 4000 years and to unravel possible human impacts on the sedimentation. A diverse array of complementary methods was applied on the 6 m long record. High resolution of mineralogical (XRD) and geochemical (XRF) analyses were performed. Quantitative mineralogical phases of sediments by the Rietveld method were computed using Topaz software. The age of the record is constrained combining radionuclide and radiocarbon dating, and checked using the correlation between the earthquake history and rapidly deposited layer identified. A high sedimentation rate of 0.12 cm/yr was inferred at the coring site. The 4000 years old record shows that significant fluctuations of the lake level and the riverine system inflow into the Amik Lake occurred. The Late Bronze lowstand leaded to punctual dryings of the lake at the end of the Bronze/Iron transition marked by the collapse of the Hittite Empire and during the Dark ages. At that time, the riverine was carrying a large terrigenous input linked to strong soil erosion related to deforestation, exploitation of mineral resources and the beginning of upland cultivation. During the Roman Period and in the later periods, upland soils were partly depleted and the riverine system completely transformed by channelization that leaded to a mashification of the Amik Basin. Chemical and mineralogical composition of sediments is quite diversified reflecting the significant geological variation of drainage basins. Abundant calcareous minerals, especially calcite, aragonite, dolomite and small amount of wollastonite characterize the different sedimentary levels recorded in the lake. Levels relatively rich in fluorite, richerite, enstatite, and wollastonite are a result of the erosion of the ophiolitic rocks from the surrounding Amanos Mountains. These levels are interpreted as corresponding to relatively high erosive periods, while more humid periods lead to more intensive weathering and consequently to the dominance of kaolinite, muscovite/illite and talc more advanced in the relative stability scale, indicating a climate with contrasting seasons. During the most recent Period a marked increase in terrigeneous minerals associated with a rise in dolomite indicates ungoing erosion as well as the drying-out of the lake. [less ▲]

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See detailHypnose: on it’s very existence
VANHAUDENHUYSE, Audrey ULg

Conference (2016, April 16)

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See detailActualités dans la prise en charge des tendinopathies
Kaux, Jean-François ULg

Conference (2016, April 16)

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See detailDrug-induced thyroid dysfunction
Geenen, Vincent ULg

Conference (2016, April 16)

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See detailSwiping or Quoting? Charles Burns’s Cut-Ups of “Old” Comics
Crucifix, Benoît ULg

Conference (2016, April 15)

In Todd Hignite's In the Studio, Charles Burns characterizes a scrapbook put together by his father as one of his “most prized possessions.” The scrapbook contains a collection of various comic strips ... [more ▼]

In Todd Hignite's In the Studio, Charles Burns characterizes a scrapbook put together by his father as one of his “most prized possessions.” The scrapbook contains a collection of various comic strips which his father used for reference when dabbling in cartooning. This scrapbook is a symbol of the close bond between reading, collecting and drawing while underlining the importance of imitation and ‘swiping’ in the production and reception of comics. Burns, whose Tumblr “Johnny 23” could be seen as a digital equivalent to his father's scrapbook, is himself profoundly engaged in ‘swiping’ panels from ‘old’ comics, from American horror and romance comic books to Hergé's Tintin albums. This paper will explore the stakes of ‘swiping’ and quotation in the author's recent production. I will not only focus on his borrowings from Tintin and romance comics for his X'ed Out trilogy, but also on related projects with small-press publishers like Le Dernier Cri, B.ü.l.b. Comix, Cornélius. The way Burns turns to the archive of comics and redeploys it follows the random logic of Burroughs's cut-up technique, which not only recalls the cut-and-paste aesthetics of the scrapbook but is also echoed in the fragmented materiality of the project. However, Burns's cut-ups are not literally ‘cut up’ as much as they are drawn. Elaborating on Philippe Marion's influential concept of “graphiation,” this paper will analyze the citational practice of Charles Burns in medium-specific and historical terms, examining what it means to redraw the past of comics into the contemporary graphic novel. Indeed, how does his work walk the line between ‘individual’ and ‘collective’ graphic styles? How does it play with various conceptions of authorship and how does it negotiate the affects bound up with the appropriated works? [less ▲]

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See detailImpact of wheat bran supplementation to sows on their milk quality, their performances and their progeny’s
Leblois, Julie ULg; Bindelle, Jérôme ULg; Dehareng, Frédéric et al

Conference (2016, April 15)

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See detailGondwanan Palaeozoic plant spores: A review
Steemans, Philippe ULg; Gerrienne, Philippe ULg

Conference (2016, April 15)

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See detailLe détournement de jeux vidéo : une analyse rhétorique et poétique
Barnabé, Fanny ULg

Conference (2016, April 15)

Le jeu vidéo, né au sein de la culture hacker, est historiquement lié à la pratique du détournement et de la réappropriation. Cette tendance première s’actualise aujourd’hui dans nombre de pratiques qui ... [more ▼]

Le jeu vidéo, né au sein de la culture hacker, est historiquement lié à la pratique du détournement et de la réappropriation. Cette tendance première s’actualise aujourd’hui dans nombre de pratiques qui prolongent le jeu hors de son espace premier et investissent d’autres supports : que l’on pense aux fanfictions, au modding, ou encore aux machinimas, le jeu vidéo est ponctuellement appréhendé par les joueurs non comme une œuvre fermée à consommer, mais comme un outil pour créer à partir de. La présente communication vise donc à étudier les détournements de jeux vidéo d’un point de vue formel, en mesurant et en caractérisant l’écart que ces œuvres « au second degré » construisent par rapport à une pratique consensuelle du jeu. Plus spécifiquement, nous tenterons ici de mettre au jour deux difficultés théoriques propres à l’étude du détournement de pratiques ludiques. [less ▲]

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See detailEffects of new potential prebiotics on Salmonella Thyphimurium in pigs
Tran, Thi Hanh Tham; Everaert, Nadia ULg; Boudry, Christelle et al

Conference (2016, April 15)

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See detailLe romancier d'aventures se présente. Entre hors-genre et dette générique, note sur un paradoxe de l'éthique paralittéraire
Di Gregorio, Luca ULg

Conference (2016, April 15)

On voudrait ici interroger un trait curieux de l’histoire des catégories populaires du romanesque frappant par son (apparence de ?) paradoxe, et sur lequel il y aurait lieu, semble-t-il, de formuler ... [more ▼]

On voudrait ici interroger un trait curieux de l’histoire des catégories populaires du romanesque frappant par son (apparence de ?) paradoxe, et sur lequel il y aurait lieu, semble-t-il, de formuler quelques remarques. Ce phénomène concerne un discours qu’a pu tenir, de façon récurrente, le roman d’aventures du XIXe siècle à propos de lui-même et de ses romanciers. En effet, ce secteur productif a ressenti très tôt le besoin, d’un côté, de « s’autoriser du voyage » en quelque sorte, en plaçant ses récits, qu’ils soient plus ou moins fantaisistes, sous le signe de l’aventure vécue, de la relation, ou même du travelogue revendiqué (le paratexte, à cet égard, est patent – on en donnera un digest représentatif) ; mais d’un autre côté, à mesure que s’étoffait cette même production, elle voyait s’élever de grands devanciers sous l’autorité desquels pouvaient désormais se positionner des héritiers et/ou épigones à la mémoire plus ou moins heureuse : ainsi, depuis le titre de « Walter Scott américain » décerné à Fenimore Cooper (sans doute le premier cas attesté de notre phénomène), tout le siècle grouillera d’étiquettes accréditantes du même genre, par lesquelles des générations renouvelées de romanciers d’aventures se proposeront au public. Dans le cas de cette quête d’auteurs-garanties, c’est évidemment l’illustration d’un lignage générique qui est poursuivie. Ainsi – sans exhaustivité – parlera-t-on, dans les journaux et les discours périphériques, d’Alexandre Dumas comme du « Walter Scott français », de Gabriel Ferry comme du « Cooper français », de Gustave Aimard, ou même d’Emmanuel Gonzalès (dans la Gazette bibliographique de 1881) selon les cas, comme d’un « Cooper français » ou d’un « Mayne-Reid français » ; de Karl May comme du « Cooper allemand », de Salgari comme du (seul) « Verne italien », et même de Louis Boussenard comme du « Verne beauceron » ( !) Il se tisse là un réseau proliférant de cooptation d’auteurs et d’essais d’affiliation hautement génériques, dont on peut déjà observer, à ces quelques exemples, que ce geste fraye et se reproduit dans toutes les industries paralittéraires d’Europe. Comment le romancier assume-il ce paradoxe ? L’assume-t-il seulement, ou se complaît-il plutôt à jouer sur l’un ou l’autre tableau ? Qui est le romancier d’aventures – ou, plutôt, que veut-il être ? Plus profondément encore : où cette oscillation définitoire – contradictoire – débouchera-t-elle à la fin du siècle, et quel « pêché définitoire originel » dénonce-t-elle aux racines mêmes du roman d’aventures ? Nos remarques procéderont par études de cas précises, en s’efforçant de faire dialoguer ces décorticages particuliers avec la réflexion théorique et les hypothèses de réponses que nous tenterons de formuler. Entre l’ethos du vadrouilleur se disant secondairement écrivain (ou écrivain par accident) et l’héritier générique cherchant son Médiateur à la matière et aux codes indépendants et bien établis, notre argument voudra explorer, en tout cas, un lieu d’intense dialectique dans les dynamiques d’accréditation du récit paralittéraire dixneuvièmiste. [less ▲]

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See detailFirst record of cryptospores in post-Hirnantian (latest Ordovician-early Silurian) sediments from Ethiopia
Brocke, R.; Bussert, R.; Lebenie, D. et al

Conference (2016, April 15)

Detailed reference viewed: 10 (3 ULg)