References of "Scientific congresses and symposiums"
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See detailThe Fish Migrate and so Must We': the Relationship between International and Internal Environmental Mobility in a Senegalese Fishing Community
Zickgraf, Caroline ULg

Conference (2015, April)

In 2008, the UN designated Saint-Louis “the city most threatened by rising sea levels in the whole of Africa”. The people of Guet Ndar, a densely populated fishing quarter, are coping with environmental ... [more ▼]

In 2008, the UN designated Saint-Louis “the city most threatened by rising sea levels in the whole of Africa”. The people of Guet Ndar, a densely populated fishing quarter, are coping with environmental challenges on two fronts: 1) coastal erosion and intensifying storms have destroyed sea-front homes, and, 2) overfishing and climate change’s maritime impacts are making local fishing less feasible as a livelihood strategy. Based on a local case study, this paper examines Guet Ndarian migration as an adaptive response to environmental risks and more specifically climate change: 1) through the intensification of fishing migration to Mauritania, and 2) through home construction on the mainland away from the encroaching sea. Although these population movements respond to different environmental challenges, this paper identifies their enmeshment as the former facilitates the latter. Furthermore, it embeds these migratory dynamics in their socio-economic context and applies mobility and transnational paradigms to environmentally vulnerable areas. [less ▲]

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See detailDoes the soil’s effective hydraulic conductivity adapt in order to obey the Maximum Entropy Production principle? A lab experiment
Westhoff, Martijn ULg; Zehe, Erwin; Erpicum, Sébastien ULg et al

Conference (2015, April)

The Maximum Entropy Production (MEP) principle is a conjecture assuming that a medium is organized in such a way that maximum power is subtracted from a gradient driving a flux (with power being a flux ... [more ▼]

The Maximum Entropy Production (MEP) principle is a conjecture assuming that a medium is organized in such a way that maximum power is subtracted from a gradient driving a flux (with power being a flux times its driving gradient). This maximum power is also known as the Carnot limit. It has already been shown that the atmosphere operates close to this Carnot limit when it comes to heat transport from the Equator to the poles, or vertically, from the surface to the atmospheric boundary layer. To reach this state close to the Carnot limit, the effective thermal conductivity of the atmosphere is adapted by the creation of convection cells (e.g. wind). The aim of this study is to test if the soil’s effective hydraulic conductivity also adapts itself in such a way that it operates close to the Carnot limit. The big difference between atmosphere and soil is the way of adaptation of its resistance. The soil’s hydraulic conductivity is either changed by weathering processes, which is a very slow process, or by creation of preferential flow paths. In this study the latter process is simulated in a lab experiment, where we focus on the preferential flow paths created by piping. Piping is the process of backwards erosion of sand particles subject to a large pressure gradient. Since this is a relatively fast process, it is suitable for being tested in the lab. In the lab setup a horizontal sand bed connects two reservoirs that both drain freely at a level high enough to keep the sand bed always saturated. By adding water to only one reservoir, a horizontal pressure gradient is maintained. If the flow resistance is small, a large gradient develops, leading to the effect of piping. When pipes are being formed, the effective flow resistance decreases; the flow through the sand bed increases and the pressure gradient decreases. At a certain point, the flow velocity is small enough to stop the pipes from growing any further. In this steady state, the effective flow resistance of the sand bed will be compared with the theoretical optimal flow resistance obtained with the MEP principle. For this study, different magnitudes of the forcing will be tested, while also the effect of dry spells will be explored. [less ▲]

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See detailBiogenic Volatile Organic Compound (BVOC) emissions from agricultural crop species: is guttation a possible source for methanol emissions following light/dark transition?
Mozaffar, Ahsan ULg; Amelynck, Crist; Bachy, Aurélie ULg et al

in Geophysical Research Abstracts (2015, April), 17(EGU2015-2110-1),

In the framework of the CROSTVOC (CROp STress VOC) project, the exchange of biogenic volatile organic compounds (BVOCs) between two important agricultural crop species, maize and winter wheat, and the ... [more ▼]

In the framework of the CROSTVOC (CROp STress VOC) project, the exchange of biogenic volatile organic compounds (BVOCs) between two important agricultural crop species, maize and winter wheat, and the atmosphere has recently been measured during an entire growing season by using the eddy covariance technique. Because of the co-variation of BVOC emission drivers in field conditions, laboratory studies were initiated in an environmental chamber in order to disentangle the responses of the emissions to variations of the individual environmental parameters (such as PPFD and temperature) and to diverse abiotic stress factors. Young plants were enclosed in transparent all-Teflon dynamic enclosures (cuvettes) through which BVOC-free and RH-controlled air was sent. BVOC enriched air was subsequently sampled from the plant cuvettes and an empty cuvette (background) and analyzed for BVOCs in a high sensitivity Proton-Transfer Reaction Mass Spectrometer (hs-PTR-MS) and for CO2 in a LI-7000 non-dispersive IR gas analyzer. Emissions were monitored at constant temperature (25 °C) and at a stepwise varying PPFD pattern (0-650 µmol m-2 s-1). For maize plants, sudden light/dark transitions at the end of the photoperiod were accompanied by prompt and considerable increases in methanol (m/z 33) and water vapor (m/z 39) emissions. Moreover, guttation droplets appeared on the sides and the tips of the leaves within a few minutes after light/dark transition. Therefore the assumption has been raised that methanol is also coming out with guttation fluid from the leaves. Consequently, guttation fluid was collected from young maize and wheat plants, injected in an empty enclosure and sampled by PTR-MS. Methanol and a large number of other compounds were observed from guttation fluid. Recent studies have shown that guttation from agricultural crops frequently occurs in field conditions. Further research is required to find out the source strength of methanol emissions by this guttation phenomenon in real environmental conditions. [less ▲]

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See detailGAIMS: a tool specifically developed for the clinical gait analysis of patients with multiple sclerosis
Pierard, Sébastien ULg; Phan-Ba, Rémy; Giet, Amaury et al

Poster (2015, April)

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See detailTracking Middleboxes in the Mobile World with TraceboxAndroid
Thirion, Valentin; Edeline, Korian ULg; Donnet, Benoît ULg

in 7th International Workshop on Traffic Monitoring and Analysis (TMA) (2015, April)

Middleboxes are largely deployed over cellular networks. It is known that they might disrupt network performance, expose users to security issues, and harm protocols deployability. Further, hardly any ... [more ▼]

Middleboxes are largely deployed over cellular networks. It is known that they might disrupt network performance, expose users to security issues, and harm protocols deployability. Further, hardly any network measurements tools for smartphones are able to infer middlebox behaviors, specially if one cannot control both ends of a path. In this paper, we present TraceboxAndroid a proof-of-concept measurement application for Android mobile devices implementing the tracebox algorithm. It aims at diagnosing middlebox-impaired paths by detecting and locating rewriting middleboxes. We analyze a dataset sample to highlight the range of opportunities offered by TraceboxAndroid. We show that TraceboxAndroid can be useful for mobile users as well as for the research community. [less ▲]

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See detailLa collaboration entre différentes disciplines médicales : ou est le problème ? Etude Partnership in Medicine
Vanmeerbeek, Marc ULg; Govers, Patrick ULg; Schippers, Nathalie ULg et al

Conference (2015, March 27)

Objectifs Les maladies ou problèmes médicaux d’origine professionnelle, ou en lien avec le travail, impliquent à des degrés divers les médecins généralistes (MG), les médecins du travail (MT) et les ... [more ▼]

Objectifs Les maladies ou problèmes médicaux d’origine professionnelle, ou en lien avec le travail, impliquent à des degrés divers les médecins généralistes (MG), les médecins du travail (MT) et les médecins-conseils des mutuelles (MC). Le manque de relation fonctionnelle entre eux peut compliquer ou retarder le retour au travail du patient. L’étude cherchait des pistes d’amélioration de la collaboration. Méthode Deux méthodes de consensus ont été successivement utilisées parmi les trois professions : huit groupes nominaux (GN) ont réunis 74 médecins de terrain; deux rondes Delphi ont concerné 28 décideurs. Résultats Un seul médecin a été perdu de vue entre les 2 tours du Delphi. Les propositions issues des GN concernaient le transfert d’informations (surtout les MT et les MC), la collaboration (surtout les MG et les MT), les connaissances, et le cadre légal et réglementaire (surtout les MC). Cinq questions sur 14 n’ont pas fait consensus (≥75%) au 1er tour du Delphi, et 10 propositions sur 13 ont été rejetées au 2e tour. Les désaccords portaient sur la nature des données à transférer, les modalités de transfert d’information, la disponibilité des données de contact des médecins. Un processus d’évitement spécifique a été mis en évidence. Certains commentaires montraient un déni de la capacité des autres à comprendre son champ professionnel, et une difficulté à considérer leur spécificité propre. Conclusions L’étude montre que le patient n’est pas un objet partagé de la relation. Le modèle Resource Dependence Institutional Cooperation (De Rijk) permet de distinguer les entraves à la volonté de coopérer (dépendance perçue) des limitations dans la capacité à le faire (manque de ressources). Le modèle quadridimensionnel de la collaboration (D’Amour) identifie un déficit d’internalisation du côté relationnel (reconnaissance des autres), et un déficit de gouvernance et de formalisation du côté organisationnel, où des initiatives volontaristes des autorités seraient bienvenues. [less ▲]

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See detailUse of C, N and S stable isotope ratios to highlight resource segregation among hermit crabs from tropical seagrass meadows
Michel, Loïc ULg; Frederich, Bruno ULg; Lavitra, Thierry et al

Poster (2015, March 26)

Polyspecific seagrass meadows are ubiquitous features of tropical coastal zones. These ecosystems are of critical ecological importance, and provide a wide range of socio-economical services to local ... [more ▼]

Polyspecific seagrass meadows are ubiquitous features of tropical coastal zones. These ecosystems are of critical ecological importance, and provide a wide range of socio-economical services to local populations. Meadows however undergo multiple threats linked to human activities (increased nutrient input, overfishing, invertebrate overharvesting, etc.). It is currently hard to assess how seagrass meadows could respond to anthropogenic impacts due to poor knowledge of their functional ecology. In an effort to unravel trophic interactions ruling the food webs associated to seagrass beds of the Toliara Great Reef (SW Madagascar), we studied resource segregation between two common Diogenidae hermit crabs (Dardanus scutellatus and Ciliopagurus tricolor) using stable isotope ratios. C, N and S stable isotope ratios of bulk muscle tissue were measured via CF-EA-IRMS (Elementar Vario MicroCube EA coupled to an Isoprime 100 MS). Interspecific differences were noted in isotopic composition of carbon (δ13C = -12.22 ± 1.73 ‰ for D. scutellatus, δ13C = -14.55 ± 0.73 ‰ for C. tricolor), nitrogen (δ15N = 4.73 ± 0.53 ‰ for D. scutellatus, δ15N = 5.20 ± 0.61 ‰ for C. tricolor) and sulfur (δ34S = 14.08 ± 2.32 ‰ for D. scutellatus, δ34S = 16.73 ± 1.49 ‰ for C. tricolor), suggesting that the two species do not feed on the same items. In addition, SIBER (Stable Isotope Bayesian Ellipses in R) modeling based on C and N data clearly showed that no overlap was present in the core isotopic niches of the two species. It also indicated that the isotopic niche of D. scutellatus was greater than the one of C. tricolor, implying that the former feeds on a greater number of items than the latter. While hermit crabs are generally considered as omnivorous species, this study highlighted differences in the foraging ecology of D. scutellatus and C. tricolor. These differences could help to limit competition for food between these two species, and facilitate their coexistence in Malagasy seagrass beds. [less ▲]

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See detailEditing a Multilingual Corpus of Letters. A Methodological Approach
Valenti, Gianluca ULg

Conference (2015, March 26)

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See detailFormulations of the bed slope term in the shallow water equations: implication for energy balance
Bruwier, Martin ULg; Archambeau, Pierre ULg; Erpicum, Sébastien ULg et al

in Workshop on Advances in Numerical Modelling of Hydrodynamics (2015, March 24)

For an incompressible, isothermal, continuous and frictionless flow, the exact resolution of the equation of conservation of mechanical energy is equivalent to the exact resolution of the equation of ... [more ▼]

For an incompressible, isothermal, continuous and frictionless flow, the exact resolution of the equation of conservation of mechanical energy is equivalent to the exact resolution of the equation of momentum conservation. However, the discrete solution of the equation of momentum conservation does not verify the equation of energy conservation. This is particularly the case as a result of the presence of a non-conservative bed slope term in the equation of momentum conservation. In this research, the influence of (i) the formulation and (ii) the discretization scheme of the non-conservative bed slope term on the energy conservation is analysed in the case of a 1D horizontal and frictionless channel with a topographic step. The results for two different formulations of the bed slope term are firstly compared: the standard formulation of the bed slope source term and a divergence formulation of the bed slope term. Then, different discretization schemes of the divergence formulation of the bed slope term are analyzed to determine the one minimizing the numerical variation of energy. [less ▲]

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

Conference (2015, March 21)

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

Conference (2015, March 13)

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

Conference (2015, March 12)

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

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

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

Conference (2015, March 10)

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

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

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

in Proceediing of the meeting (2015, March 09)

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See detailWheat yield sensitivity to climate change across a European transect for a large ensemble of crop models
Pirttioja, Nina; Carter, Timothy; Fronzek, Stefan et al

in Soussana, Jean-Francois (Ed.) Proceedings of the Climate Smart Agriculture 2015 conference (2015, March)

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See detailMAVEN IUVS observations of the aftermath of Comet Siding Spring's meteor shower
Stewart; Schneider; Plane et al

Conference (2015, March)

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See detailFirst results from MAVEN's Imaging UV spectrograph
Schneider; McClintock; Stewart et al

Conference (2015, March)

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See detailIUVS dayglow analysis
Jain; Evans; Stevens et al

Conference (2015, March)

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See detailAnalysis of Martian nightglow and aurora
Stiepen, Arnaud ULg

Conference (2015, March)

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See detailMetabolomic, proteomic and preclinical imaging of patient-derived tumor xenografts for improving treatment of liver metastases patients
Perez Palacios, A; Blomme, A; Boutry, S et al

in Acta Gastro-Enterologica Belgica (2015, March), 78(1), 134

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See detailAzione, testualizzazione, notazione
Dondero, Maria Giulia ULg

in Espressione e contenuto. Rivista on-line dell'AISS Associazione Italiana di Studi Semiotici (2015, March)

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See detailCan the exploration of left space be induced implicitly in unilateral neglect?
Wansard, Murielle ULg; Bartolomeo, Paolo; Vanderaspoilden, Valérie et al

Poster (2015, March)

The purpose of the present study was to explore the ability of neglect patients to detect and exploit the predictive value of a cue to respond more quickly and accurately to targets on their ... [more ▼]

The purpose of the present study was to explore the ability of neglect patients to detect and exploit the predictive value of a cue to respond more quickly and accurately to targets on their contralesional side in a Posner spatial cueing task. The majority of the cues (i.e. 80%) were invalid, indicating that the target would appear on the opposite side, although patients were not informed of this bias. Our results demonstrate that some neglect patients were able to extract the cue’s predictability and use it to orient faster toward the left. This cueing effect was present even in patients who were subsequently unable to describe the predictive character of the cues, and thus was not modulated by reportable awareness of the cue-target relation. [less ▲]

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See detailEffects of transcranial magnetic stimulation coil orientation and pulse width on short-latency afferent inhibition
Hannah, Ricci; D'Ostilio, Kevin ULg; Goetz, Stefan et al

Poster (2015, March)

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See detailPreliminary analysis of Martian dayglow observed by the Imaging Ultraviolet Spectrograph onboard MAVEN
Jain, Sonal; Stewart, Ian; Schneider, Nick et al

Conference (2015, March)

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See detailPreliminary analysis of Martian nightglow and aurora observed by MAVEN's Imaging UltraViolet Spectrograph
Stiepen, Arnaud ULg; Stewart; Jain et al

Conference (2015, March)

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See detailOptimisation of the Nitrogen fertilisation in the context of climate change
Dumont, Benjamin ULg; Basso, Bruno; Bodson, Bernard ULg et al

in Soussana, Jean-Francois (Ed.) Proceedings of the Climate Smart Agriculture 2015 conference (2015, March)

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See detailGian Matteo Giberti et les lettres à travers la correspondance de jeunesse
Valenti, Gianluca ULg

Conference (2015, February 27)

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See detailLes peptides natriurétiques: le point de vue du biologiste
LE GOFF, Caroline ULg

Conference (2015, February 26)

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See detailLes peptides natriurétiques: le point de vue du biologiste
LE GOFF, Caroline ULg

Conference (2015, February 26)

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See detailTechnology Assessment in East Asia: Experiences and New Approaches
Moniz, Antonio; Yoshizawa, Go; Van Oudheusden, Michiel ULg

Conference (2015, February 25)

Integrating social and ethical concerns in innovation practice is a well-documented and debated issue in the United States and in Europe (namely through the EU-wide PACITA project). Related developments ... [more ▼]

Integrating social and ethical concerns in innovation practice is a well-documented and debated issue in the United States and in Europe (namely through the EU-wide PACITA project). Related developments in other parts of the world are less discernible – at least to Westerns. Yet, as witnessed by the emergence of technology assessment (TA) in countries like Japan, TA and TA-like activities have a unique and long history and continue to play a role in contemporary STI processes (e.g. in the area of citizen engagement with nanotechnologies, or energy policy). Taking these observations as its entry point, this panel asks how STI governance is locally enacted in Asian knowledge-driven economies. Like their Western counterparts, nations like China, Indonesia, Japan, the Republic of Korea, Singapore, Taiwan, etc., have undergone, and continue to undergo, rapid science- and technology-driven industrialization. In these processes, TA and TA-like activities develop with STI policies and programs and typically do so in nation- and region-specific ways. To render these processes, policies, and programs visible, and understand their implications for STI governance, this panel will discuss contributions that: • Describe and conceptualize how TA and TA-like activities have emerged in Asian KBEs, and in what particular forms (e.g. academic and parliamentary TA programs, linked to certain technologies and/or actors, which methods are used and why, etc.). • Reflect how these activities has evolved with, sustained, and/or countered, STI policies on the regional, national, and international level. • Compare and contrast how TA is, or is not, institutionalized in Asian countries and regions, e.g. through initiatives to initiate or abolish various TA forms, such as health TA, early-warning TA, and parliamentary TA; and/or point to prospects for TA capacity building. • Situate the above processes within a broader theory of, and movement towards, new STI governance frameworks, such as anticipatory governance, responsible innovation, public engagement, and/or others. By placing the development in historical, sociological, and comparative perspective, the panel seeks to open a space for critical reflection on the potential, problems, and limitations of initiating TA in Asia and draw connections to STI governance processes in other KBEs across the globe. [less ▲]

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See detail5. Régulateurs de croissance
Henriet, François; Monfort, Bruno; Meza Morales, Walter ULg

in Watillon, Bernard; Bodson, Bernard (Eds.) Livre Blanc Céréales (2015, February 25)

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See detail7. Lutte intégrée contre les ravageurs - 2.1 Suivi des populations de cécidomyie équestre, Haplodiplosis marginata, grâce au développement d'un piège à phéromone
Censier, Florence ULg; Fischer, Christophe ULg; Chavalle, Sandrine et al

in Watillon, Bernard; Bodson, Bernard (Eds.) Livre Blanc Céréales (2015, February 25)

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See detailCover Songs Retrieval and Identification
Osmalsky, Julien ULg

Conference (2015, February 24)

Cover songs retrieval is a MIR task that has been widely studied in the recent years. The task, in its general sense, consists in retrieving covers for a given audio query. In this PhD, we focus on the ... [more ▼]

Cover songs retrieval is a MIR task that has been widely studied in the recent years. The task, in its general sense, consists in retrieving covers for a given audio query. In this PhD, we focus on the more specific task of cover songs *identification*. Given an unknown cover song query, we want to find relevant information about the original song, such as the title, the artist etc. Applications are live music recognition, plagiarism detections, query by examples, etc. Our approach is based on a pruning algorithm, whose role is to discard as quickly as possible as many tracks as possible from a search database in order to keep a smaller subset that should contain the tracks relevant to the query. We introduce the concept of *rejectors* for the pruning algorithm, which are single or combined classifier using multiple audio features for selecting relevant tracks. [less ▲]

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See detailRegional organizations, international norms and global governance of culture: The EU foreign policy and the diversity of cultural expressions
Vlassis, Antonios ULg

Conference (2015, February 19)

Abstract: The aim of this paper is to explore empirically and qualitatively the links between regional organizations and international norms, by using an institutionalism centered on the actors. It seeks ... [more ▼]

Abstract: The aim of this paper is to explore empirically and qualitatively the links between regional organizations and international norms, by using an institutionalism centered on the actors. It seeks thus to analyze the European Union (EU)’s capacity to act within the global governance of culture, and in particular its ability to promote the Convention on diversity of cultural expressions (CDCE) beyond the EU. What is at issue is of why and how the EU foreign cultural policy (EUFCP) uses the CDCE and its normative framework, of what purposes as well as of how the CDCE influences the EUFCP and its objectives. I argue that the CDCE offers an opportunity for the European Commission to establish itself as a foreign policy actor in cultural affairs. Nevertheless, I point out that the disconnect between the Commission and the EU culture organizations is a serious constraint for the effectiveness of the EUFCP, highlighting that the promotion of the CDCE has been especially instrumental in consolidating the Commission’s actorness in external cultural affairs. And finally, I conclude that not only the Commission’s practices largely rely on the willingness of some member states with strong interests in the cultural area, but also the EU’s interpretations on the scope and the goals of the CDCE are far from convergent. Consequently, the Commission’s ability to be a EUFCP’s agent clearly depends on the sensitiveness of the issue and the EU’s actorness is strongly linked to the context in which the EUFCP is made. [less ▲]

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See detailFrom psychometric research to implementation and back: selected examples
Magis, David ULg

Conference (2015, February 13)

Current psychometric research is most often supported by computer software. New research perspectives often imply intensive simulation studies to validate the tested theories or hypotheses, and therefore ... [more ▼]

Current psychometric research is most often supported by computer software. New research perspectives often imply intensive simulation studies to validate the tested theories or hypotheses, and therefore require accurate implementation as e.g., R packages. However, it may happen that unexpected psychometric phenomena are detected almost accidentally, through such implementations with basically totally different purposes. This talk will illustrate this phenomenon by means of two recent examples from item response theory (IRT) with polytomous models: (a) the equivalence between the weighted likelihood estimator (WLE) and the Bayes modal estimator with Jeffreys prior, and (b) the relationships between observed and expected information functions. Rather than focusing on the technical details, the purpose of this talk is to highlight how the results were identified first through R implementation, then confirmed by theoretical derivations. The talk concludes by advocating for flexible and stable open-source implementations (such as R packages) to support current and ongoing psychometric research. [less ▲]

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See detailAn Alternative to Semantics?
Gauvry, Charlotte ULg

Conference (2015, February 12)

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See detailEncourager un vieillissement cognitif sain par un travail adapté (work shop)
Grotz, Catherine ULg; Adam, Stéphane ULg

Conference (2015, February 12)

L'objectif du workshop est d'apporter des éléments pratiques/cliniques en faveur d'un vieillissement cognitif de qualité, y compris une discussion des mesures à mettre en place en ce qui concerne l ... [more ▼]

L'objectif du workshop est d'apporter des éléments pratiques/cliniques en faveur d'un vieillissement cognitif de qualité, y compris une discussion des mesures à mettre en place en ce qui concerne l'employabilité de la population active plus âgée. [less ▲]

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See detailRisk of emergence of a hyperpathogenic bovine leukemia virus by mutation of a single envelope N-linked glycosylation site
De Brogniez, Alix ULg; Bouzar, Amel-Baya; Jacques, Jean-Rock ULg et al

Poster (2015, February 11)

- Introduction : Pathogens have co-evolved with their host to ensure efficient replication and transmission without inducing excessive pathogenicity that would indirectly impair their persistence. This is ... [more ▼]

- Introduction : Pathogens have co-evolved with their host to ensure efficient replication and transmission without inducing excessive pathogenicity that would indirectly impair their persistence. This is exemplified by the bovine leukemia virus (BLV) system in which lymphoproliferative disorders develop in ruminants after latency periods of several years. Infection of sheep and cattle with BLV is a model system for the related human T-lymphotropic virus type 1 (HTLV-1) responsible for Adult T-cell Leukemia (ATL). - Aims : The goal of this work is to investigate the role of N-glycans of the viral envelope protein during viral replication and pathogenesis. - Methods and results : Using glycosylation inhibitors and lectins, we showed that N-glycosylation is involved in viral infection (i.e. cell-to-cell fusion). Using reverse genetics of an infectious molecular provirus, we next demonstrated that a particular N-linked envelope glycosylation site (N230) limits viral replication and pathogenicity in vitro and in vivo. We have thus generated a viral mutant that is more pathogenic than the wild type strain. - Conclusions : To our knowledge, this is the first time that a hyperpathogenic BLV has been identified. This unexpected observation has important consequences in terms of disease control and managing. Indeed, during evolution, pathogens and their hosts should achieve an equilibrium allowing the coexistence of the two species. Occurrence of this particular mutation may thus represent a potential threat associated with emergence of hyperpathogenic BLV strains and possibly of new variants of the related HTLV-1. [less ▲]

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See detailZones humides : entre modifications environnementales et actions humaines
Ozer, Pierre ULg

Conference (2015, February 08)

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See detailQuand science politique et droit dialoguent : quelle typologie des instruments mémoriels en fonction du degré de contrainte ?
Grandjean, Geoffrey ULg

Conference (2015, February 07)

Envisager les études sur la mémoire comme sous-champ de la science politique francophone ouvre des pistes enrichissantes pour les politologues, notamment lorsqu’ils sont amenés à analyser les instruments ... [more ▼]

Envisager les études sur la mémoire comme sous-champ de la science politique francophone ouvre des pistes enrichissantes pour les politologues, notamment lorsqu’ils sont amenés à analyser les instruments mémoriels régissant un ou plusieurs système(s) politique(s). Dans cette perspective, la communication vise à présenter, d’un point de vue épistémologique, les apports découlant de l’interaction entre les sciences politique et juridique dans le processus de consolidation des études sur la mémoire comme sous-champ disciplinaire de la science politique. Plus précisément, la communication vise à offrir une typologie des instruments mémoriels en fonction du degré de contrainte et d’imposition d’une mémoire officielle. Par exemple, une résolution adoptée par une assemblée législative est faiblement contraignante alors qu’une loi réprimant le négationnisme impose à la fois une mémoire officielle tout en sanctionnant pénalement les citoyens qui ne la respectent pas. La typologie passe en revue les multiples instruments mémoriels pouvant être adoptés par les autorités publiques : résolution, loi déclarative, loi pénale, plan de commémorations ou encore mise en valeur d’un lieu de mémoire. L’accent est mis sur les instruments mémoriels de deux pays francophones : la Belgique et la France. Au final, cette communication permet d’insister sur l’apport de la science politique en analysant l’exercice de prérogatives de puissance publique et sur l’apport de la science juridique en classifiant les types d’instruments mémoriels en fonction du degré de contrainte ; tout en faisant dialoguer des cas d’étude différents. [less ▲]

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See detailIntérêt du signal T2 des adénomes hypophysaires à GH traités par analogues de la somatostatine - premiers résultats de l'étude IRMA#2
Potorac, Iulia ULg; PETROSSIANS, Patrick ULg; Daly, Adrian ULg et al

in Symposium "Perspectives in Endocrinology" - 5ème édition (2015, February 07)

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See detailLa pérennisation des partenariats publics-privés dans le champ de l’emploi : entre application, interprétation et ajustement du cadre réglementaire
Remy, Céline ULg; Gérard, Julie ULg; Beuker, Laura ULg

Conference (2015, February 07)

Dans une perspective de gestion mixte du marché du travail, les services publics de l’emploi sont invités, par la Convention 181 de l’OIT de 1997, à déléguer et à confier l’exploitation et la gestion de ... [more ▼]

Dans une perspective de gestion mixte du marché du travail, les services publics de l’emploi sont invités, par la Convention 181 de l’OIT de 1997, à déléguer et à confier l’exploitation et la gestion de leurs activités à des opérateurs privés de service, dans le cadre d’une entente contractuelle. Alors que les modalités de la collaboration (telles que le public-cible, le type et le nombre d’accompagnements dispensés, les résultats à atteindre, etc.) sont fixées, initialement, par les services publics de l’emploi, elles sont ensuite mises en pratique par les diverses parties-prenantes du partenariat. Les acteurs publics et privés exploitent la part de latitude inhérente à leur fonction pour interpréter et ajuster les termes du contrat ou pour pouvoir réaliser leur mission d’accompagnement des demandeurs d’emploi. Partant du postulat que la règle est incomplète, notre objectif est d’analyser la mise en œuvre du partenariat en saisissant les arguments avancés par les acteurs pour justifier et légitimer leurs actions. À partir de cette analyse, nous montrerons que les acteurs du partenariat doivent interpréter les règles – écart entre le travail prescrit et le travail effectivement presté – dans leurs pratiques quotidiennes. Agissant comme des « pseudo » street-level bureaucrats, ces derniers usent de leur pouvoir pour ajuster les règles. En outre, il semblerait que ces pratiques d'indiscipline permettent, en réalité, de maintenir les relations partenariales entre services publics de l’emploi et opérateurs privés, et d’œuvrer, in fine, à la pérennisation de celles-ci dans le champ de l’emploi. Nous appuierons notre analyse sur un matériau empirique composé d’observations participantes et d’entretiens semi-directifs réalisés auprès des parties-prenantes des PPP, situés en Belgique francophone. [less ▲]

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See detailThe return of Turkey to the Western Balkans: a challenge or an opportunity for the European Union ?
Lika, Liridon ULg

Conference (2015, February 07)

In the new Turkish doctrine, besides the great interests in Central Asia, Middle East, Africa and the Caucasus, the Balkans are also important. Turkey is making great efforts to play a greater role on the ... [more ▼]

In the new Turkish doctrine, besides the great interests in Central Asia, Middle East, Africa and the Caucasus, the Balkans are also important. Turkey is making great efforts to play a greater role on the international scene and creates its area of interest, especially where the links of Ottoman legacy can help. Although it is defined as a peaceful power in the region, some describe it as neo-ottoman, a term rejected by the Turkish authorities because of its possible imperialist connotation. This paper aims precisely to study the return of Turkey to the Balkans. Our central question is: what is the purpose of the Turkish foreign policy in the Western Balkans? Related issues will be addressed such as: is there a competition between Turkey and the European Union in this area? What are the specifics of Turkish foreign policy? In order to explore these research questions, this study focuses on the concept of soft power through which Turkey extends its power. Indeed, the Turkish government imposes itself on the Balkans not by force but with the help of economics, diplomacy, trade, culture and religion. Following the crisis in the EU, causing the collapse of Western investment and a relative decrease of attraction for the Balkans, Turkey has taken advantage of the situation in order to increase its influence in all areas. This contribution will proceed in three stages. Firstly, we will make an analysis of the authors of soft power to think about the character of the new Turkish geopolitical doctrine. Secondly, we are going to apply this theoretical framework to the case study identified, namely the influence of Turkey in the Western Balkan countries. Finally, we will show if exists a competition or a cooperation between Turkey and European Union in the Western Balkans. [less ▲]

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See detailNouvelle classification des acro-gigantismes
Rostomyan, Liliya ULg; Beckers, Albert ULg

in Symposium "Perspectives in Endocrinology" - 5ème édition (2015, February 07)

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See detailA novel mutation of the luteinizing hormone/choionic gonadotrophin receptor gene leading to Leydig cell hypoplasia type I
Potorac, Iulia ULg; Rivero-Müller, A; Pintiaux, Axelle ULg et al

in Symposium "Perspectives in Endocrinology" - 5ème édition (2015, February 07)

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See detailComprendre les programmes électoraux : comparaison des méthodes d’encodage manuel et automatique
Piet, Grégory ULg; Dandoy, Régis; Joly, Jeroen

Conference (2015, February 06)

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See detailA mixed integer nonlinear programming bi-objective model for intermodal network design
Mostert, Martine ULg; Caris, An; Limbourg, Sabine ULg

Conference (2015, February 05)

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See detailSite-specific height-diameter allometry of Central African moist forests
Loubota Panzou, Grâce Jopaul ULg; Doucet, Jean-Louis ULg; Fayolle, Adeline ULg

Poster (2015, February 04)

In this study we aimed to identify the variation in height-diameter allometry between forest types and among species in Central African moist forests. We also examined the consequences on biomass ... [more ▼]

In this study we aimed to identify the variation in height-diameter allometry between forest types and among species in Central African moist forests. We also examined the consequences on biomass estimation. Two forest sites in southern Cameroon with contrasting levels of deciduousness. Height and diameter were measured for a total of 521 trees belonging to 12 timber species over a large range of diameter, 10-240 cm for the Ma’an site and 11-182 cm for the Mindourou site. Non-destructive height measurements were calibrated with destructive measurements for a total of 60 trees, 30 in each site. Commercial forest inventory data (n=7253 0.5ha plots) were gathered for the Ma’an (n=34 samples and 2101 plots) and Mindourou (n=117 samples and 5152 plots) sites. A total of ten allometric models (including asymptotic and non-asymptotic models) were fitted to the height-diameter data at species (n=12) and site (n=2) level. Biomass estimates were computed based on forest inventory data and general allometric models using both site-specific and published height-diameter equations. Given the strong correlation between the non-destructive and destructive height measurements we had confidence in using the non-destructive height measurements to establish site- and species-specific height-diameter allometric equations. The height measurements performed over a wide range of diameters, 10-240 cm, tended to support an asymptotic shape (and most often the Michaelis Menten model) for the height-diameter allometry either at species and site level. We identified a significant difference in height-diameter allometry between the two study sites. For a given diameter, trees tended to be taller in the more semi-deciduous Mindourou site than in the more evergreen Ma’an site, with a maximum height of 39.5 and 46.5 m, respectively. The two sites significantly differed in stand structure and biomass. This difference is due to the variation in height-diameter allometry. Height-diameter allometry strongly varies between sites and site-specific height-diameter allometric equations should be developed to further improve the estimation of biomass and carbon stock contained in tropical forests. [less ▲]

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See detailSuppression of Limit Cycle Oscillations using the Nonlinear Tuned Vibration Absorber
Habib, Giuseppe ULg; Kerschen, Gaëtan ULg

in Proceeding IMAC XXXIII A Conference and Exposition on Structural Dynamics, Orlando 2-5 February 2015 (2015, February 03)

The objective of the present study is to mitigate, or even completely eliminate, the limit cycle oscillations in mechanical systems using a passive nonlinear absorber, termed the nonlinear tuned vibration ... [more ▼]

The objective of the present study is to mitigate, or even completely eliminate, the limit cycle oscillations in mechanical systems using a passive nonlinear absorber, termed the nonlinear tuned vibration absorber (NLTVA). An unconventional aspect of the NLTVA is that the mathematical form of its restoring force is not imposed a priori, as it is the case for most existing nonlinear absorbers. The NLTVA parameters are determined analytically using stability and bifurcation analyses, and the resulting design is validated numerically using the MATCONT software. The proposed developments are illustrated using a Van der Pol-Du ng primary system. [less ▲]

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See detailAntoine Galland et l'épigraphie
Famerie, Etienne ULg

in Bauden, Frédéric; Waller, Richard (Eds.) Colloque international A. Galland (2015, February)

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See detailSpatial distribution of income tax concessions for owner-occupied housing in Belgium: still an incentive for suburban development?
Xhignesse, Guillaume ULg

Conference (2015, February)

In Belgium, public authorities have considerably supported owner-occupied housing since the end of the nineteenth century, notably through tax concessions. The mechanism studied in this preliminary paper ... [more ▼]

In Belgium, public authorities have considerably supported owner-occupied housing since the end of the nineteenth century, notably through tax concessions. The mechanism studied in this preliminary paper (in force for mortgages taked out from 2005 to 2014) allows households to deduct at marginal taxation rate an annually-limited amount of mortgage repayments for their owner-occupied home, including interests and capital under an aggregated form. We emphasize the spatial distribution of this tax concession. To this aim, we use a sample of 34,132 geolocated tax returns (income 2010). Our results show that suburban areas benefit far more from this mechanism than urban areas, mainly because most of the beneficiaries live in these areas. In addition, we observe also that the benefits go for the most part to middle-to-high income families. We hypothesize that this tax relief acts as a catalyst in the spatial sorting of the population on the basis of socio-economic characteristics. [less ▲]

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See detailExperimental modal analysis of nonlinear structures using broadband data
Noël, Jean-Philippe ULg; Renson, Ludovic ULg; Grappasonni, Chiara ULg et al

in Proceedings of the International Modal Analysis Conference (IMAC) XXXIII (2015, February)

The objective of the present paper is to develop a rigorous identification methodology of nonlinear normal modes (NNMs) of engineering structures. This is achieved by processing experimental measurements ... [more ▼]

The objective of the present paper is to develop a rigorous identification methodology of nonlinear normal modes (NNMs) of engineering structures. This is achieved by processing experimental measurements collected under broadband forcing. The use of such a type of forcing signal allows to excite multiple NNMs simultaneously and, in turn, to save testing time. A two-step methodology integrating nonlinear system identification and numerical continuation of periodic solutions is proposed for the extraction of the individual NNMs from broadband input and output data. It is demonstrated using a numerical cantilever beam possessing a cubic nonlinearity at its free end. The proposed methodology can be viewed as a nonlinear generalization of the phase separation techniques routinely utilized for experimental modal analysis of linear structures. The paper ends with a comparison between this new nonlinear phase separation technique and a previously-developed nonlinear phase resonance method. [less ▲]

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See detailEarly detection of university students in potential difficulty
Hoffait, Anne-Sophie ULg; Schyns, Michael ULg

Conference (2015, February)

Rate of success in the first year at University in Belgium is very low regarding other foreign universities. The University of Liege, as other Universities, has already taken different initiatives. But by ... [more ▼]

Rate of success in the first year at University in Belgium is very low regarding other foreign universities. The University of Liege, as other Universities, has already taken different initiatives. But by early identifying students who have a high probability to face difficulties if nothing is done, the Universities might develop adapted methods to attack the problem with more emphasis where it is more needed and when it is still possible. Thus we want to develop a decision tool able to identify these students to help them. For that, we consider three standard datamining methods: logistic regression, artificial neural networks and decision trees and focus on early detection, i.e. before starting at the University. Then, we suggest to adapt these three methods as well as the classification framework in order to increase the probability of correct identification of the students. In our approach, we do not restrict the classification to two extreme classes, e.g. failure or success, but we create subcategories for different levels of confidence: high risk of failure, risk of failure, expected success or high probability of success. The algorithms are modified accordingly and to give more weight to the class that really matters. Note that this approach remains valid for any other classification problems for which the focus is on some extreme classes; e.g. fraud detection, credit default... Finally, simulations are conducted to measure the performances of the three methods, with and without the suggested adaptation. We check if the factors of success/failure we can identify are similar to those reported in the literature. We also make a ``what-if sensitivity analysis''. The goal is to measure in more depth the impact of some factors and the impact of some solutions, e.g., a complementary training or a reorientation. [less ▲]

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See detailRugose corals from the Carboniferous of the eastern Tafilalt (Morocco): a progress report
Aretz, Markus; Denayer, Julien ULg

Conference (2015, February)

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See detailAnalytical procedure to derive P-I diagram of a beam under explosion
Hamra, Lotfi ULg; Demonceau, Jean-François ULg; Denoël, Vincent ULg

in Proceeding of the IABSE Workshop - Safety, Robustness and Condition Assessments of Structures (2015, February)

The aim of this paper is to study a beam extracted from a frame and subjected to blast loading. The demand of ductility depends on six dimensionless parameters: two related to the blast loading, two ... [more ▼]

The aim of this paper is to study a beam extracted from a frame and subjected to blast loading. The demand of ductility depends on six dimensionless parameters: two related to the blast loading, two referring to the bending behaviour of the beam and two corresponding to the dynamic behaviour of the rest of the structure. We develop a full analytical procedure that provides the ductility demand as a function of these six dimensionless parameters. [less ▲]

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See detailCore-shell AgSiO2-Protoporphyrin IX nanoparticle: Effect of the Ag core on reactive oxygen species generation
Lismont, Marjorie ULg; Pàez Martinez, Carlos ULg; Dreesen, Laurent ULg

in SPIE proceeding - Colloidal Nanoparticles for Biomedical Applications X (2015, February)

Photodynamic therapy (PDT) for cancer is based on the use of a light sensitive molecule to produce, under specific irradiation, toxic reactive oxygen species (ROS). A way to improve the therapy efficiency ... [more ▼]

Photodynamic therapy (PDT) for cancer is based on the use of a light sensitive molecule to produce, under specific irradiation, toxic reactive oxygen species (ROS). A way to improve the therapy efficiency is to increase the amount of produced ROS near cancer cells. This aim can be achieved by using a metal enhanced process arising when an optically active molecule is located near a metallic nanoparticle (NP). Here, the coupling effect between silver (Ag) NPs and protoporphyrin IX (PpIX) molecules, a clinically approved photosensitizer, is studied compared first, to PpIX fluorescence yield and second, to ROS production efficiency. By applying a modified Stöber process, PpIX was encapsulated into a silica (SiO2) shell, surrounding a 60 nm sized Ag core. We showed that, compared to SiO2-PpIX NPs, Ag coated SiO2-PpIX NPs dramatically decreased PpIX fluorescence together with singlet oxygen production efficiency. However, after incubation time in the dark, the amount of superoxide anions generated by the Ag doped sample was higher than the control sample one. [less ▲]

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See detailRole of the progesterone receptor in the development of sexual behavior in female mice
Desroziers, Elodie ULg; Brock, Olivier; Baum, M.J. et al

Poster (2015, February)

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See detailRobust impact design of steel and composite building structures: the alternate load path approach
Hoffmann, Nadine; Kuhlmann, Ulrike; Demonceau, Jean-François ULg et al

in Proceeding of the IABSE Workshop - Safety, Robustness and Condition Assessments of Structures (2015, February)

Vulnerability of structures to progressive collapse and mitigation of the effects of local damages are topics widely discussed. The studies worldwide carried out allowed identifying different design ... [more ▼]

Vulnerability of structures to progressive collapse and mitigation of the effects of local damages are topics widely discussed. The studies worldwide carried out allowed identifying different design strategies. However, specific knowledge is still limited and this gap is apparent in codes of practice. A European project focusing on robustness of steel and steel and concrete composite structures regarding the effects of impact recently started combining the 2 methods of residual strength and alternate load path. In the framework of the project activities, the Authors aimed their studies on the redundancy of the structure through slab-beam-systems and ductile joint as well as on the local behaviour of the impacted members. For this analytical, numerical and experimental investigations have been planned and executed. The paper describes the experimental activities related to the investigations on the structural redundancy and presents the preliminary test outcomes. [less ▲]

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See detailExperimental demonstration of a 3D-printed nonlinear tuned vibration absorber
Grappasonni, Chiara ULg; Habib, Giuseppe ULg; Detroux, Thibaut ULg et al

in Proceedings of the International Modal Analysis Conference (IMAC) XXXIII (2015, February)

Engineering structures are designed to be lighter and more flexible, hence reducing the extent of application of linear dynamic models. Concurrently, vibration mitigation is required for enhancing the ... [more ▼]

Engineering structures are designed to be lighter and more flexible, hence reducing the extent of application of linear dynamic models. Concurrently, vibration mitigation is required for enhancing the performance, comfort or safety in real-life applications. Passive linear vibration absorbers are purpose-built, often designed using Den Hartog's equal-peak strategy. However, nonlinear systems are known to exhibit frequency-energy-dependent oscillations which linear absorbers cannot effectively damp out. In this context, the paper introduces a new nonlinear tuned vibration absorber (NLTVA) whose nonlinear functional form is tailored according to the frequency-energy dependence of the nonlinear primary structure. The NLTVA design aims at ensuring equal peaks in the nonlinear receptance function for an as large as possible range of forcing amplitudes, hence generalizing Den Hartog's method to nonlinear systems. Our focus in this study is on experimental demonstration of the NLTVA performance using a primary structure consisting of a cantilever beam with a geometrically nonlinear component at its free end. The absorber is implemented using a doubly-clamped beam fabricated thanks to 3D printing. The NLTVA performance is also compared with that of the classical linear tuned vibration absorber. [less ▲]

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See detailLes PPP comme nouveau mode de régulation du marché de l'accompagnement des demandeurs d'emploi. A chaque modèle de partenariat son type de stratégie
Remy, Céline ULg

in Cahiers Loyola (2015, February), 1

Cette communication vise à montrer en quoi les partenariats publics-privés (PPP) constituent désormais un nouveau mode de régulation du marché de l’accompagnement des demandeurs d’emploi. Les services ... [more ▼]

Cette communication vise à montrer en quoi les partenariats publics-privés (PPP) constituent désormais un nouveau mode de régulation du marché de l’accompagnement des demandeurs d’emploi. Les services publics de l’emploi (SPE) doivent établir des PPP avec des prestataires de service pour la mise en place de formation à destination des demandeurs d’emploi. La réalisation de trois études de cas au sein des SPE, dont deux en Belgique et une en Suisse, nous permet de mettre en évidence une forte influence du modèle de gestion du PPP sur la collaboration entre les parties-prenantes mais aussi sur les stratégies développées par les prestataires pour surmonter les problèmes liés à la collaboration avec l’Office de l’Emploi et à la mise en place de la prestation de service. [less ▲]

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See detailExperimental nonlinear identification of an aircraft with bolted connections
De Filippis, Giovanni; Noël, Jean-Philippe ULg; Kerschen, Gaëtan ULg et al

in Proceedings of the International Modal Analysis Conference (IMAC) XXXIII (2015, February)

Aircraft structures are known to be prone to nonlinear phenomena, especially as they constantly become lighter and hence more flexible. One specific challenge that is regularly encountered is the modeling ... [more ▼]

Aircraft structures are known to be prone to nonlinear phenomena, especially as they constantly become lighter and hence more flexible. One specific challenge that is regularly encountered is the modeling of the mounting interfaces between aircraft subcomponents. Indeed, for large amplitudes of vibration, such interfaces may loosen and, in turn, trigger complex mechanisms such as friction and clearances. In this context, the present work intends to investigate the nonlinear dynamics of the Morane–Saulnier Paris aircraft, accessible at ONERA. This aircraft possesses multiple bolted connections between two external fuel tanks and wing tips. The objective of the paper is specifically to carry out an adequate identification of the numerous nonlinearities affecting the dynamics of this full-scale structure. Nonlinearity detection and the subsequent subspace-based parameter estimation have been performed on experimental data, collected during an on-ground test campaign. Nonlinearity detection is first achieved by the comparison of frequency response functions estimated at low excitation level, with those obtained at high amplitude level, yielding insight towards accurately characterizing the behavior of the bolted connections. Then, a nonlinear subspace identification method is applied to measured data to estimate the linear and nonlinear parameters of the structure and novel strategies and tools that overcome specific arisen problems are developed. [less ▲]

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See detailRobust impact design of steel and composite building structures
Hoffman, Nadine; Kuhlmann, Ulrike; Demonceau, Jean-François ULg et al

in Proceeding of the IABSE Workshop - Safety, Robustness and Condition Assessments of Structures (2015, February)

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See detailRobust impact design of steel and composite building structures: the alternate load path approach
Hoffmann, Nadine; Kuhlmann, Ulrike; Demonceau, Jean-François ULg et al

in Proceeding of the IABSE Workshop - Safety, Robustness and Condition Assessments of Structures (2015, February)

Vulnerability of structures to progressive collapse and mitigation of the effects of local damages are topics widely discussed. The studies worldwide carried out allowed identifying different design ... [more ▼]

Vulnerability of structures to progressive collapse and mitigation of the effects of local damages are topics widely discussed. The studies worldwide carried out allowed identifying different design strategies. However, specific knowledge is still limited and this gap is apparent in codes of practice. A European project focusing on robustness of steel and steel and concrete composite structures regarding the effects of impact recently started combining the 2 methods of residual strength and alternate load path. In the framework of the project activities, the Authors aimed their studies on the redundancy of the structure through slab-beam-systems and ductile joint as well as on the local behaviour of the impacted members. For this analytical, numerical and experimental investigations have been planned and executed. The paper describes the experimental activities related to the investigations on the structural redundancy and presents the preliminary test outcomes. [less ▲]

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See detailBridging the gap between Nonlinear Normal Modes and Modal Derivatives
Sombroek, Cees; Renson, Ludovic ULg; Tiso, Paolo et al

in Proceedings of the International Modal Analysis Conference (IMAC) XXXIII (2015, February)

Nonlinear Normal Modes (NNMs) have a clear conceptual relation to the classical linear normal modes (LNMs), yet they offer a solid theoretical framework for interpreting a wide class of non-linear ... [more ▼]

Nonlinear Normal Modes (NNMs) have a clear conceptual relation to the classical linear normal modes (LNMs), yet they offer a solid theoretical framework for interpreting a wide class of non-linear dynamical phenomena with no linear counterpart. The main difficulty associated with NNMs is that their calculation for large-scale models is expensive, particularly for distributed nonlinearities. Repeated direct time integrations need to be carried out together with extensive sensitivity analysis to reproduce the frequency-energy dependence of the modes of interest. In the present paper, NNMs are computed from a reduced model obtained using a quadratic transformation comprising LNMs and Modal Derivatives (MDs). Previous studies have shown that MDs can capture the essential dynamics of geometrically nonlinear structures and can greatly reduce the computational cost of time integration. A direct comparison with the NNMs computed from another standard reduction technique highlights the capability of the proposed reduction method to capture the essential nonlinear phenomena. The methodology is demonstrated using simple examples with 2 and 4 degrees of freedom. [less ▲]

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See detailThe Late Viséan Rugose coral association of NW Turkey
Denayer, Julien ULg

Conference (2015, February)

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See detailActivités physiques, représentations et femmes
Cloes, Marc ULg

Conference (2015, January 31)

Il est admis internationalement que les filles et les femmes représentent un public à risque en matière de sédentarité. Cette conférence interactive vise à répondre à trois questions: (1) L’activité ... [more ▼]

Il est admis internationalement que les filles et les femmes représentent un public à risque en matière de sédentarité. Cette conférence interactive vise à répondre à trois questions: (1) L’activité physique, qu’est-ce que c’est? (2) A quoi ça sert? (3) Qu’est-ce qu’il faut faire, finalement? Au-delà de la volonté de faire vivre aux participants une expérience originale, les objectifs finaux de l'intervention consistent à permettre une prise de conscience et à proposer des pistes d’action. [less ▲]

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See detailDépasser la situation : de la situation-limite à la personnalité borderline. Généalogie, critique et clinique d’un concept sartrien
Cormann, Grégory ULg; Englebert, Jérôme ULg

Conference (2015, January 31)

Nous souhaitons interroger ici le concept sartrien de situation à partir d’une double approche historique et psychopathologique qui semble en diagnostiquer la disparition tout aussi bien conceptuelle ... [more ▼]

Nous souhaitons interroger ici le concept sartrien de situation à partir d’une double approche historique et psychopathologique qui semble en diagnostiquer la disparition tout aussi bien conceptuelle qu’existentielle : la notion de situation, organisatrice de l’ontologie phénoménologique de Sartre et pivot de son engagement, semble s’être aujourd’hui désintégrée en tant que concept (voir ses usages pseudo-conceptuels dans les domaines de la pédagogie et du management), alors que ce qu’on appelle la « condition postmoderne », telle qu’elle s’exprime dans de nouvelles symptomatologies psychopathologiques, rend apparemment caduque, face à la fragmentation des repères de l’existence, l’exigence de penser en/la situation. Nous procèderons en trois temps. Nous ferons d’abord la généalogie du concept, dont l’application à la psyché humaine et à la représentation théâtrale de celle-ci remonte, selon Leo Spitzer, à la fin du 17ème siècle. Dans cette première section, nous insisterons en particulier sur le rapport que l’élaboration du concept de situation entretient, au début du 20ème siècle, avec l’émergence de la psychopathologie notamment chez Jaspers (« situation-limite ») et chez Minkowski (nous rappellerons à cet égard le rôle de Gabriel Marcel dans le champ philosophique français de l’entre-deux-guerres). Nous serons également attentifs à la critique méthodologique que le concept de situation permet d’adresser à la métapsychologie freudienne. Sur cette base, nous reprendrons ensuite les principales étapes chez Sartre de la prise en considération de l’homme en situation et des possibilités de dépassement de cette situation. Nous envisagerons successivement l’Esquisse d’une théorie des émotions, « Questions de méthode » et L’Idiot de la famille. Il conviendra certes de rappeler comment l’existentialisme, comme le situationnisme à sa façon, a cherché, dans le sillage du marxisme, à réaliser la philosophie et du coup à transformer le concept en vécu. Mais nous montrerons aussi, à rebours, comment l’œuvre sartrienne, confrontée aux exigences conjointes du marxisme et de la psychanalyse (cf. l’analyse des pressions familiales dans le Flaubert), a dû dépasser le cadre de la magie émotionnelle au sein duquel la notion de situation s’était d’abord élaborée. Au-delà de la « situation sartrienne » – et peut-être en la prolongeant –, la critique de Deleuze des dispositifs nous servira enfin, dans un troisième temps, de point de bascule vers la condition postmoderne et la fragmentation de la situation en tant que repère d’existence. Le sujet borderline – véritable éclat de la postmodernité – nous permettra ainsi de conclure en reprenant le propos psychopathologique maturé par l’évolution conceptuelle de la situation. Nous caractériserons l’existence borderline par une fragmentation du soi corrélée à une explosion, voire à un morcellement, des espaces de vie qui répondent à la nécessité ontologique d’une « ubiquité instantanée » dénuée de présence corporelle (comme le permettent les espaces virtuels « connectés »). [less ▲]

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See detailBiochemical methane potential of residues of three banana varieties from Cameroon : fresh and dry peduncles
Awedem wobiwo, Florent; Happi Emaga, Thomas; Fokou, Elie et al

Poster (2015, January 30)

In Cameroon , the ratio of energy cost to standard of living for both electric and fuel energy is higher than in USA and EU. The local energy needs could be met by valorizing local wastes in an ... [more ▼]

In Cameroon , the ratio of energy cost to standard of living for both electric and fuel energy is higher than in USA and EU. The local energy needs could be met by valorizing local wastes in an environmentally and economically sustainable way. Banana and plantain plants produce significant quantities of post-harvest biomass wastes such as bulbs, pseudo stems, leaf sheaths, petioles–midribs, leaf blades, peduncles, rachis and blossoms which can be converted to methane-rich biogas by anaerobic digestion (AD). AD is a natural process of degradation of organic materials. [less ▲]

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See detailEvaluation et gamification - Transformer un quiz de chimie en un mini-jeu
le Maire, Nathalie ULg; Fauconnier, Marie-Laure ULg; Colaux, Catherine ULg et al

Conference (2015, January 30)

Le recours à des questionnaires à choix multiples pour l’évaluation des étudiants est une pratique courante à l’université. Cette communication décrit et analyse une expérimentation contrôlée visant à ... [more ▼]

Le recours à des questionnaires à choix multiples pour l’évaluation des étudiants est une pratique courante à l’université. Cette communication décrit et analyse une expérimentation contrôlée visant à explorer les effets de la présentation d’un QCM formatif sous la forme d’un jeu. L’étude s’inscrit ainsi dans les recherches actuelles sur les avantages et les limites pédagogiques de la « gamification », à savoir la transposition des principes issus de l’univers du jeu au domaine de l’éducation (Johnson, Adams Becker, Estrada, & Freeman, 2014). La présente recherche est effectuée dans le cadre d’un doctorat dédié spécifiquement à la gamification d’évaluations formatives. L’étude repose sur la mise à disposition de plusieurs versions d’un quiz portant sur un chapitre d’un cours de chimie générale en première année d’université. Le dispositif expérimental prévoit un enrichissement graduel de la gamification selon quatre prototypes conçus après identification et extraction de schèmes visant à stimuler et maintenir la motivation et la performance dans des jeux actuels et populaires tels que Candy Crush, Angry Birds ou Hay Day. Située à l’entrée du doctorat, cette étude vise, outre la collecte de données quant à l’utilisabilité du mini-jeu proposé, à mettre en lumière ses effets sur l’état de flow dans le contexte des edugames et contribuera à la validation de la traduction française de l’échelle d’EGameFlow (Fu, Su, & Yu, 2009). [less ▲]

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See detailInfluence of cover crop management on sugar beet production
Hiel, Marie-Pierre ULg; Bodson, Bernard ULg

Poster (2015, January 30)

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See detailInvestigating the Effects of Plant Root Exudates on PAHs Bioavailability to Soil Microorganisms in Contaminated Brownfields : Research Methodology.
Davin, Marie ULg; Lognay, Georges ULg; Fauconnier, Marie-Laure ULg et al

Poster (2015, January 30)

As a result of heavy industrial past activities, an estimated 6,000 brownfields require remediation in Wallonia. This number rises to over 3.5 million in Europe. Polycyclic Aromatic Hydrocarbons (PAHs ... [more ▼]

As a result of heavy industrial past activities, an estimated 6,000 brownfields require remediation in Wallonia. This number rises to over 3.5 million in Europe. Polycyclic Aromatic Hydrocarbons (PAHs) represent 17% of treated pollutants in Wallonia (Aldric et al., 2011). Current remediation techniques are rather expensive and technically demanding (Megharaj et al., 2011). Based on the observation that PAHs soil content decreases in the presence of plants (Cheema et al., 2010), the PhD aims at developing alternative PAHs remediation techniques in brownfields. It is articulated around three research axes. The first axis focusses on plant exudates and how they may improve PAHs bioavailability to soil microorganisms and enhance their degradation. This will be investigated by (i) characterizing several contaminated soils (physico-chemical parameters) and PAH content and factors of bioavailability, (ii) selecting a plant model and collecting root exudates, and (iii) evaluating the effects of exudates on PAHs bioavailability. The objective of the second axis is to evaluate the effects of plant exudates on PAHs degrading microorganisms by (i) comparing PAHs biodegradation in the presence/absence of exudates and (ii) assessing the potential toxic effects of exudate compounds on the microbial communities. The aim of the third axis is to study plant-pollutants interactions by (i) establishing the plant tolerance to several contamination levels and (ii) following PAHs bioavailability when facing real exudation rates, on the field. [less ▲]

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See detailLinking bees and flowers: mutualistic interaction networks to study ecosystem functioning
Uyttenbroeck, Roel ULg; Monty, Arnaud ULg

Poster (2015, January 30)

In recent years, much attention is going to pollinators, as they are important for the increasing food production while being threatened by agricultural intensification and other environmental drivers ... [more ▼]

In recent years, much attention is going to pollinators, as they are important for the increasing food production while being threatened by agricultural intensification and other environmental drivers. While honeybees (Apis mellifera L.) are generalist according to their flower preferences, wild pollinators’ flower preferences can go from generalist to very specialist. The same goes for plant species, which can be generalist or specialist in the pollinator species they need to get pollinated. The combination of a set of generalist and specialist plant species with a pollinator community consisting of generalists and specialists in a certain habitat, results in an interaction network between pollinators and the visited plant flowers. Studying this mutualistic interaction network is a time-consuming method, but can provide valuable data to calculate indicators of ecosystem functioning. One of the important conclusions that came already out of studies applying this method is that pollination systems are often more generalized than thought based on pollination syndromes. This poster will explore the method of studying mutualistic interaction networks with a focus on the sampling protocol, the indicators that can be derived from the data and their meaning. [less ▲]

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See detailFéminiser la voix
Morsomme, Dominique ULg; Remacle, Angélique ULg

Conference (2015, January 29)

Parlée ou chantée, notre voix révèle qui nous sommes. Elle participe à notre identité et véhicule nos émotions (ref. Revis. J). Dans cet exposé, nous présenterons la voix du point de vue du genre. En ... [more ▼]

Parlée ou chantée, notre voix révèle qui nous sommes. Elle participe à notre identité et véhicule nos émotions (ref. Revis. J). Dans cet exposé, nous présenterons la voix du point de vue du genre. En effet, l’Unité Logopédie de la Voix (www.logopedie-voix.be) s’intéresse entre autres à la féminisation vocale chez les personnes transidentitaires, en processus de changement de genre. Ces personnes ne s’identifiant pas au sexe et au genre qui leur ont été attribués à la naissance, elles éprouvent un désir profond de vivre comme une personne du sexe opposé à leur sexe biologique. Lors du processus de transition où ont lieu les transformations nécessaires au changement de genre, la logopédie a pour but d’améliorer la cohérence entre l’apparence de la personne et sa voix. Ainsi, notre recherche se focalise sur ce qui distingue la voix féminine de la voix masculine. Nous visons à développer des stratégies de féminisation vocale, portant sur des paramètres tels que la fréquence fondamentale de la voix (grave ou aigüe), les contours intonatifs, le niveau d’amplitude de certains formants, le débit de parole, son rythme, ou encore le vocabulaire choisi. Féminiser une voix, c’est chercher à comprendre ce qui permet d’en identifier le genre, mais également participer à la construction de l’identité de la personne à part entière. [less ▲]

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See detailÉvaluations à large échelle : prendre la mesure des effets de contexte
Lafontaine, Dominique ULg

Conference (2015, January 28)

The communication (Keynote conference) give a comprehensive overview of how contexts have been taken into account in large-scale international assessments of achievement. The following topics are ... [more ▼]

The communication (Keynote conference) give a comprehensive overview of how contexts have been taken into account in large-scale international assessments of achievement. The following topics are investigated: 1) the growing importance of contextual questionnaires in PISA 2) the response-style biases and how they can jeopardize validity and comparability of measures (especially of self-reported non-cognitive outcomes measured by Likert scales) 3) the frame-of-reference (group) effects (BFLPE) and their differential impact depending on the structure of education systems. [less ▲]

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See detailL’évaluation entre pairs dans des travaux de groupes : Impacts sur la motivation et sur la perception des étudiants
Colaux, Catherine ULg

Conference (2015, January 28)

La faculté de Gembloux Agro Bio Tech qui forme principalement des bioingénieurs propose à ses étudiants de première année un nouveau cours intitulé « Question d’actualité en environnement ; projet ». Ce ... [more ▼]

La faculté de Gembloux Agro Bio Tech qui forme principalement des bioingénieurs propose à ses étudiants de première année un nouveau cours intitulé « Question d’actualité en environnement ; projet ». Ce cours qui se veut avant tout être un cours d’intéressement se construit autour du questionnement des étudiants sur une thématique fixée, par le prisme de leurs matières enseignées en première année. Habitués aux cours ex-cathedra organisés dans de grands amphithéâtres, les 300 étudiants de première année se retrouvent répartis en groupes de 6 étudiants et doivent réaliser les travaux associés à ce cours en utilisant deux outils de collaboration asynchrones à savoir Diigo et un wiki. La construction de ce cours leur laisse une grande liberté d’organisation. Seules 8h de présentiel sont placées à l’horaire. Les étudiants doivent donc s’organiser entre eux pour soumettre dans les délais imposés deux travaux qu’ils devront réaliser collaborativement et en ligne. L’évaluation de ce cours n’est pas associée à un examen traditionnel. La note finale est construite sur base des deux travaux rendus par les étudiants plus un travail individuel de réflexion sur l’expérience de travail de groupe. Pour chacun des travaux rendus, les étudiants bénéficient de la même note collective reflétant la qualité du travail soumis plus une note individuelle qui reflète quant à elle la participation de l’étudiant dans le travail de groupe. Si lors de la première année cette participation individuelle était sanctionnée par l’enseignant qui avait accompagné le groupe, nous avons cette année, donné la responsabilité à l’étudiant d’évaluer la participation de ses pairs. Cette communication analysera l’impact de ce style de notation sur la motivation et la perception du cours par les étudiants. [less ▲]

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See detailPistes de réflexion et propositions d'outils pour optimaliser l'évaluation des tâches complexes en langues modernes et tendre vers plus d'équité
Simons, Germain ULg; Pagnoul, Pierre ULg

Conference (2015, January 28)

Dans cette communication, nous présentons une analyse critique du document "Familles de tâches en langues modernes" de la FWB et ouvrons différentes pistes pour optimiser cet outil. Par ailleurs, nous ... [more ▼]

Dans cette communication, nous présentons une analyse critique du document "Familles de tâches en langues modernes" de la FWB et ouvrons différentes pistes pour optimiser cet outil. Par ailleurs, nous proposons un dispositif d'observation/évaluation dans lequel les élèves sont amenés à s'approprier les critères de qualité d'une tâche complexe en interaction orale. [less ▲]

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See detailUsing shear strain localisation to model the fracturing around gallery in unsaturated Callovo-Oxfordian claystone
Pardoen, Benoît ULg; Levasseur, Séverine ULg; Collin, Frédéric ULg

in Chau, Kam Tim; Zhao, Jidong (Eds.) Bifurcation and Degradation of Geomaterials in the New Millennium (2015, January 28)

Galleries drilling leads to damage propagation, fracturing and properties modifications in the surrounding medium. The prediction of the damaged zone behaviour is an important matter and needs to be ... [more ▼]

Galleries drilling leads to damage propagation, fracturing and properties modifications in the surrounding medium. The prediction of the damaged zone behaviour is an important matter and needs to be properly assessed. To do so the fractures can be modelled using shear strain localisation. The coupled local second gradient model is used under unsaturated conditions to correctly model the strain localisation behaviour. The permeability evolution and the rock desaturation due to air ventilation in galleries are considered. Finally, a hydro-mechanical modelling of a gallery excavation in Callovo-Oxfordian claystone is performed leading to a fairly good representation of the damaged zone. [less ▲]

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See detailAPPUI ANALYTIQUE A LA LUTTE CONTRE LES MEDICAMENTS DE QUALITE INFERIEURE
Mbinze Kindenge, Jérémie; Hubert, Philippe ULg; Marini Djang'Eing'A, Roland ULg

Conference (2015, January 27)

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See detail[18F]UCB-H as a new PET radiotracer for Synaptic vesicle protein 2A: A first clinical trial
Bahri, Mohamed Ali ULg; Stifkens, Mathieu; Bastin, Christine ULg et al

Poster (2015, January 27)

SV2A is widely distributed in the brain and has been demonstrated to be involved in vesicle trafficking. The critical role of SV2A in proper nervous system function is shown, e.g., by the fact that it is ... [more ▼]

SV2A is widely distributed in the brain and has been demonstrated to be involved in vesicle trafficking. The critical role of SV2A in proper nervous system function is shown, e.g., by the fact that it is a binding site and the primary mechanism of levetiracetam. Levetiracetam is an antiepileptic drug which has recently been suggested to reduce synaptic deficits in a mouse model for Alzheimer’s disease. We here aimed to investigate the cerebral distribution of [18F]UCB-H, which has a high affinity with the SV2A. Dynamic PET data of the head of 4 healthy volunteers were acquired over 100 minutes after injection of 170.4 ± 24.9 MBq of GMP produced [18F]UCB-H. The arterial input function (IF) was obtained by blood sampling. The IF was also derived from the dynamic data using the correlation coefficient method. Blood data revealed a consistent amount of [18F]UCB-H in whole blood and plasma indicating a very low degree of binding of the tracer to the red blood cells. The image-derived arterial IFs were showed to be very similar to the measured ones with a peak-ratio around 0.91 and an area-under-curve ratio about 0.98. The [18F]UCB-H PET data showed a high and rapid uptake in the grey matter structures, matching the known ubiquitous distribution of the SV2A in the brain. The kinetics of the tracer in the brain was characterized by an initial high uptake phase followed by rapid washout allowing the standard compartmental modeling (1-tissue, 2-tissue, and Logan Plot). The three models gave similar results with both the measured and image-derived IFs. The total distribution volume of the tracer in the brain was greater than 7 mL/cm3. Our results suggest that [18F]UCB-H is a good candidate as radiotracer for brain SV2A proteins and could be used for human studies. Image-derived IF showed to be useful for quantitative studies without the need to the arterial blood sampling. SV2A modifications may consequently be assessed in neurological pathologies such as Alzheimer’s disease. [less ▲]

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See detailEffects of α-synuclein levels on cerebral synaptic function: Validation of a novel PET radioligand for the early diagnosis of Parkinson’s disease
Tarragon Cros, Ernesto ULg; Ferrara, André ULg; Tirelli, Ezio ULg et al

Poster (2015, January 27)

Background In Parkinson’s disease, converging evidence supports a pathogenic role for excessive α–synuclein accumulation in synaptic terminals that may propagate back to the soma of vulnerable nerve cells ... [more ▼]

Background In Parkinson’s disease, converging evidence supports a pathogenic role for excessive α–synuclein accumulation in synaptic terminals that may propagate back to the soma of vulnerable nerve cells such as neurons in the substantia nigra pars compacta. The resulting loss of dopaminergic terminals in the striatum can be demonstrated in vivo using 18F-Dopa-PET (positron emission tomography). However, there’s currently no validated biomarker of the progressive synaptic dysfunction in other vulnerable areas such as the cerebral cortex. Goal In this longitudinal study, we will test the hypothesis that the loss of synaptic terminals in a mouse model of excessive α–synuclein accumulation can be demonstrated in vivo before the occurrence of behavioural disturbances using 18F-UCB-H, a new PET biomarker developed at CRC. We will also test if this new imaging modality is sensitive enough to study the effect of a disease modifying therapy such as chronic physical exercise. Methods We will use microPET for the in vivo quantification of 18F-UCB-H brain uptake in 16 wild type animals and 16 transgenic (Tg) mice overexpressing human α–syn under the mThy1 promotor every 2 months. Data will be validated against post-mortem analyses after the last PET study. Predictions We predict decreased tracer uptake over time in the basal ganglia and cerebral cortex in Tg mice as compared with WT animals. Also, we predict a relationship between 18F-UCB-H uptake levels in basal ganglia and cerebral cortex and progressive alterations in both motor and cognitive functions, respectively. Further, we also expect that chronic exercise will slow down both motor and cognitive disturbances, as well as the rate of 18F-UCB-H brain uptake decreases. Conclusion If 18F-UCB-H PET proves to be a valid biomarker for the early detection of α–synuclein accumulation in the pre-clinical model of PD, the methods will tested on human clinical populations. [less ▲]

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See detailDéveloppement de nouveaux marqueurs neuroradiologiques de la maladie de Parkinson par reconnaissance de motifs
Himri, Khadidja ULg; Depierreux, Frédérique ULg; GARRAUX, Gaëtan ULg

Poster (2015, January 27)

Background and objectives: Automatic classification of Parkinson’s disease (PD) versus healthy controls (HC) based on structural MRI has so far focused on unimodal approaches. However, this method is ... [more ▼]

Background and objectives: Automatic classification of Parkinson’s disease (PD) versus healthy controls (HC) based on structural MRI has so far focused on unimodal approaches. However, this method is subject to a poor temporal and spatial resolution leading to low classification accuracy. To overcome this limitation we propose to integrate different modalities by generating a single decision function based on a multi-kernel method, exploiting the complementary information it offers. We predict that the integration of multiple modalities produces greater classification enhancement. Materials and methods: 3Tesla MRI was acquired in 42 patients with PD and 42 age and gender matched healthy controls. We relied on Unified Parkinson’s Disease Rating Scale (UPDRS) for evaluating the clinical status. We used structural and quantitative maps of T1, T2*, proton density (PD), magnetization transfer (MT), Multi-parameter (MT magnetization transfer, proton density (A), Iron Deposit (R2 *), mixing water content, iron, and the fraction of macromolecules tissues (R1) at 1 × 1 × 1 mm3 resolution. We identified cortical and subcortical brain regions (cortex, putamen, globus pallidus, substantia nigra), and cortical grey matter. We applied existing classification algorithms in the field of neuroscience using a classification algorithm based on Support Vector Machines (SVMs) [1], executed using the Pattern Recognition for Neuroimaging Toolbox (PRoNTo) [2]. The processes of classification was the following, data were mean centered and leave one subject out cross-validation was performed, making the test set independent from the training set. Analyses were restricted to voxels where all subjects had non-zero values. Statistical significance of the classifications was tested using permutation testing (1000 permutations) with random assignment of group class to the input image. Subsequently, we combined different modalities (MT, A, R1, R2) and identified the combination giving the highest sensitivity and sensibility in PD classification. As classifier we used support vector machines that are inspired by statistical learning theory Vladimir Vapnik and Multiple Kernel Learning approach, introduced by Lanckriet [3],[4]. Our approach can be seen as an analogue of MKL with SVMs. Conclusion & Future work: Identification of brain areas with affected intensity in the Parkinson’s group compared to Healthy Controls in single modalities using pronto is helpful. However, the subsequent multi-kernel approach utilizes unimodal information in a combined fashion so that emergent information is obtained, transcending effectiveness unimodal approaches. In conclusion, our findings suggest that combining different imaging modalities and different regions of interest increase classification accuracy significantly. These results are promising for objective diagnosis in medical practice. [less ▲]

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See detailLe testing adaptatif informatisé : une brève introduction
Magis, David ULg

Conference (2015, January 27)

L’objet de cet exposé est de présenter les grands principes et concepts du testing adaptatif informatisé (TAI). Les éléments abordés sont : le TAI face au test fixe (papier-crayon), les principes généraux ... [more ▼]

L’objet de cet exposé est de présenter les grands principes et concepts du testing adaptatif informatisé (TAI). Les éléments abordés sont : le TAI face au test fixe (papier-crayon), les principes généraux du TAI (banque d’items, estimation provisoire et finale de la compétence, sélection des items à administrer, règles d’arrêt), les principes spécifiques au TAI (contrôle de l’exposition des items, équilibrage du contenu des tests). L’exposé se veut didactique et général afin de dessiner les contours du TAI. Il se termine par un état de l’art sur les recherches actuelles sur le TAI. [less ▲]

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See detailExploration of volumetric cerebral changes, with de micro-MRi, due to psychomotor exercise in mice
Moës, Florian ULg; Plenevaux, Alain ULg; Becker, Guillaume ULg et al

Poster (2015, January 27)

It's well know that exercise is good for health .In addition exercise has postive effects on cognition ,neurodegenerative disease and on mood. Some studies show that exercise has effect on brain so the ... [more ▼]

It's well know that exercise is good for health .In addition exercise has postive effects on cognition ,neurodegenerative disease and on mood. Some studies show that exercise has effect on brain so the aim of this study is to see if there are volumetric changes due to exercise or not. [less ▲]

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