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See detailDo aphids actively search for ant partners?
Fischer, Christophe ULg; Vanderplanck, Maryse; Lognay, Georges ULg et al

in Insect Science (in press)

The aphid–ant mutualistic relationships are not necessarily obligate for neither partners but evidence is that such interactions provide them strong advantages in terms of global fitness. While it is ... [more ▼]

The aphid–ant mutualistic relationships are not necessarily obligate for neither partners but evidence is that such interactions provide them strong advantages in terms of global fitness. While it is largely assumed that ants actively search for their mutualistic partners namely using volatile cues; whether winged aphids (i.e. aphids’ most mobile form) are able to select ant-frequented areas had not been investigated so far. Ant-frequented sites would indeed offer several advantages for these aphids including a lower predation pressure through ant presence and enhanced chances of establishing mutuaslistic interactions with neighbour ant colonies. In the field, aphid colonies are often observed in higher densities around ant nests, which is probably linked to a better survival ensured by ants’ services. Nevertheless, this could also result from a preferential establishment of winged aphids in ant-frequented areas. We tested this last hypothesis through different ethological assays and show that the facultative myrmecophilous black bean aphid, Aphis fabae L., does not orientate its search for a host plant preferentially towards ant-frequented plants. However our results suggest that ants reduce the number of winged aphids leaving the newly colonized plant. Thus, ants involved in facultative myrmecophilous interactions with aphids appear to contribute to structure aphid populations in the field by ensuring a better establishment and survival of newly established colonies rather than by inducing a deliberate plant selection by aphid partners based on the proximity of ant colonies. [less ▲]

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See detailChild labour, Agency and Family dynamics: The Case of Mining in Katanga (DRC)
Andre, Géraldine ULg; Godin, Marie

in Childhood (in press)

In the last three decades, the development of the artisanal and small-scale mining (ASM) sector has been increasing in the Democratic Republic of Congo (DRC), bringing more and more urban families into ... [more ▼]

In the last three decades, the development of the artisanal and small-scale mining (ASM) sector has been increasing in the Democratic Republic of Congo (DRC), bringing more and more urban families into this flourishing business sector, and among them, children. At first glance, one could see children in the mining sector mainly as victims entangled in the flows of raw materials of unbridled capitalism. But this paper aims to look at the often unconceivable, and as a result neglected, social agency of children even when they are involved in stigmatized and prohibited types of child labour. To do so, it relies on the results of a socio-anthropological collective research project on children’s mining activities which was carried out in a small locality called La Ruashi in the city of Lubumbashi (Province of Katanga). The article aims to provide a more comprehensive understanding of what is often normatively only labelled as ‘child labour’ by looking at different spheres of social relations within which children are embedded. Examining the set of social interactions that children have with their families, the broader community and their ‘peers’, several ‘family portraits’ are offered, highlighting a heterogeneity of social interpretations regarding this ‘new’ form of child work. It will be shown that for families from middle-class background, this kind of work is often socially disruptive, at the forefront of inter-generational conflict. As for families from lower classes, social changes induced by children’s mining activities are often better incorporated into the family habitus. Common social changes encountered in all families irrespective of class belonging will also be portrayed, showing the transversal societal impact these ‘new’ forms of child economic activities can provoke at a micro level. [less ▲]

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See detailCan the collapse of a fly ash heap develop into an air-fluidized flow? - Reanalysis of the Jupille accident (1961)
Stilmant, Frédéric ULg; Pirotton, Michel ULg; Archambeau, Pierre ULg et al

in Geomorphology (in press)

A fly ash heap collapse occurred in Jupille (Liege, Belgium) in 1961. The subsequent flow of fly ash reached a surprisingly long runout and had catastrophic consequences. Its unprecedented degree of ... [more ▼]

A fly ash heap collapse occurred in Jupille (Liege, Belgium) in 1961. The subsequent flow of fly ash reached a surprisingly long runout and had catastrophic consequences. Its unprecedented degree of fluidization attracted scientific attention. As drillings and direct observations revealed no water-saturated zone at the base of the deposits, scientists assumed an air-fluidization mechanism, which appeared consistent with the properties of the material. In this paper, the air-fluidization assumption is tested based on two-dimensional numerical simulations. The numerical model has been developed so as to focus on the most prominent processes governing the flow, with parameters constrained by their physical interpretation. Results are compared to accurate field observations and are presented for different stages in the model enhancement, so as to provide a base for a discussion of the relative influence of pore pressure dissipation and pore pressure generation. These results show that the apparently high diffusion coefficient that characterizes the dissipation of air pore pressures is in fact sufficiently low for an important degree of fluidization to be maintained during a flow of hundreds of meters. [less ▲]

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See detailObserver la médiation culturelle en psychiatrie : vers une cadre analyse des dispositifs
Vandeninden, Elise ULg

in Péquignot Bruno (dir.) (Ed.) Les mondes de la médiation culturelle (in press)

Fidèles aux objectifs de démocratisation de la culture, les actions de médiation culturelle se déplacent aussi en dehors des lieux cultivés pour atteindre des publics dits « empêchés », « éloignés » ... [more ▼]

Fidèles aux objectifs de démocratisation de la culture, les actions de médiation culturelle se déplacent aussi en dehors des lieux cultivés pour atteindre des publics dits « empêchés », « éloignés ». C’est le cas du dispositif auquel nous avons consacré notre thèse de doctorat : celui des ateliers de création artistique mis en place dans les hôpitaux psychiatriques, plus communément connus (mais aussi « disputés » ) sous l’appellation d’ « art-thérapie ». La particularité de ces dispositifs de médiation est double : d’une part, ils ne sont pas le fruit du travail d’une institution culturelle mais sont organisés à l’initiative du monde médical ; d’autre part la médiation culturelle a ici pour objectif l’initiation des patients à la création artistique (en vue d’une possible exposition des œuvres vers un public) plus que leur mise en contact, fondée sur la réception, avec une œuvre déjà existante. Par ces deux aspects, notre objet d’étude s’éloigne donc des conceptions traditionnelles de la médiation culturelle. Ce prisme n’en demeure pas moins pertinent dans la mesure où la notion de « médiation » sera ici mobilisée comme une « problématique » dont il s’agira de démontrer la richesse et la complexité. [less ▲]

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See detailJamaica Kincaid's A Small Place
Munos, Delphine ULg

in Helen Goethals (Ed.) A Companion to Commonwealth Studies: Cultural Relations since 1884 (in press)

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See detailEvaluation of [18F]UCB-H as a novel PET tracer for synaptic vesicle protein 2A in the brain.
Warnock, Geoffrey; Aerts, Joël ULg; Bahri, Mohamed Ali ULg et al

in Journal of Nuclear Medicine (The) (in press)

Synaptic vesicle 2 (SV2) proteins are critical to proper nervous system function and are involved in vesicle trafficking. The SV2A isoform has been identified as the binding site of the antiepileptic ... [more ▼]

Synaptic vesicle 2 (SV2) proteins are critical to proper nervous system function and are involved in vesicle trafficking. The SV2A isoform has been identified as the binding site of the antiepileptic levetiracetam (LEV), making it an interesting therapeutic target for epilepsy. [18F]UCB-H is a novel PET imaging agent with a nanomolar affinity for human SV2A. Methods: preclinical PET studies were carried out in isoflurane anesthetized rats. Arterial input function was measured using an arteriovenous shunt and beta microprobe system. [18F]UCB-H was injected IV (140 ± 20 MBq bolus). Results: brain uptake of [18F]UCB-H was high, matching the expected homogeneous distribution of SV2A. The distribution volume (Vt) for [18F]UCB-H was calculated using Logan’s graphical analysis and the effect of LEV pretreatment on Vt measured. In control animals the mean whole-brain Vt was 9.76 ± 0.52 ml/cm3 (mean ± SD, n=4, test-retest), and the mean reproducibility in test-retest studies was 10.4 ± 6.5 %. Uptake of [18F]UCB-H was dose-dependently blocked by pretreatment with LEV (0.1 - 100 mg/kg IV). Conclusion: our results indicate that [18F]UCB-H is a suitable radiotracer for the imaging of SV2A in vivo. This is the first PET tracer for in vivo quantification of SV2A. The necessary steps for implementation of [18F]UCB-H production under GMP conditions and first in human studies are planned. [less ▲]

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See detailA Geometrical Acoustics Approach Linking Surface Scattering and Reverberation in Room Acoustics
Embrechts, Jean-Jacques ULg

in Acta Acustica United with Acustica (in press)

A general model of the influence of surface scattering on the reverberation time would have several applications in room acoustics. Such a model is not yet available, and it is the purpose of this paper ... [more ▼]

A general model of the influence of surface scattering on the reverberation time would have several applications in room acoustics. Such a model is not yet available, and it is the purpose of this paper to investigate a geometrical acoustics approach. Starting from the radiative transfer equation, an exponential solution is first developed for the reverberation energy decay in rooms with diffusely reflecting boundaries. Differences with the diffuse sound field (Sabine) theory are highlighted, leading to a modified formula for the reverberation time which is shown to be more in accordance with ray tracing simulations. A general model is then proposed for rooms in which specular and diffuse reflections coexist. This general model is applied in rooms where the specular contribution can be assumed to be quasi-isotropic and uniform. Under this assumption, the reverberation decay is represented by the sum of two exponential functions, depending on the scattering coefficients. However, it is shown that the influence of surfaces’ scattering on reverberation is rather limited in this case. On the contrary, rooms with a pair of parallel surfaces are prone to create significant anisotropy in the cloud of image sources. An analytical formulation is proposed in this case for the specular and diffuse contributions, provided that some assumptions are again made on the specularly reflected sound field. The final expression is not really intuitive concerning the relation between scattering coefficients and reverberation, but it contains all the variables influencing this relation. This allows fast evaluations of the effect of surface scattering in particular situations. Finally, the application of this model to room acoustics computer simulations is illustrated by an example. [less ▲]

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See detailTrajectory-Based Supplementary Damping Control for Power System Electromechanical Oscillations
Wang, Da ULg; Glavic, Mevludin ULg; Wehenkel, Louis ULg

in IEEE Transactions on Power Systems (in press)

This paper considers a trajectory-based approach to determine control signals superimposed to those of existing controllers so as to enhance the damping of electromechanical oscillations. This approach is ... [more ▼]

This paper considers a trajectory-based approach to determine control signals superimposed to those of existing controllers so as to enhance the damping of electromechanical oscillations. This approach is framed as a discrete-time, multi-step optimization problem which can be solved by model-based and/or by learning-based methods. This paper proposes to apply a model-free tree-based batch mode Reinforcement Learning (RL) algorithm to perform such a supplementary damping control based only on information collected from observed trajectories of the power system. This RL-based supplementary damping control scheme is first implemented on a single generator and then several possibilities are investigated for extending it to multiple generators. Simulations are carried out on a 16-generators medium size power system model, where also possible benefits of combining this RL-based control with Model Predictive Control (MPC) are assessed. [less ▲]

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See detailMétacognition et réussite scolaire : Perspectives théoriques
Frenkel, Stéphanie ULg; Deforge, Hélène

in Gireaudeau, Caroline; Chasseigne, Gérard (Eds.) Psychologie, Education et Vie Scolaire (in press)

Après avoir introduit les facteurs qui jouent un rôle dans la réussite scolaire, ce chapitre porte essentiellement sur la définition des composantes métacognitives. Une revue de littérature récente et ... [more ▼]

Après avoir introduit les facteurs qui jouent un rôle dans la réussite scolaire, ce chapitre porte essentiellement sur la définition des composantes métacognitives. Une revue de littérature récente et détaillée permet de justifier nos choix théoriques en matière de connaissances métacognitives, de stratégies métacognitives, d'expériences métacognitives et d'interaction cognition-métacognition. [less ▲]

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See detailcompte rendu de : Eleanor DICKEY, The Colloquia of the Hermeneumata Pseudodositheana. Volume I. Colloquia Monacensia-Einsidlensia, Leidense-Stephani, and Stephani
Rochette, Bruno ULg

in Gnomon : Kritische Zeitschrift für die Gesamte Klassische Altertumswissenschaft (in press)

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See detailUna nazione ricostruita: musica e feste delle confraternite tedesche e fiamminghe a Roma
Corswarem, Emilie ULg

in Goulet, Anne-Madelaine; zur Nieden (Eds.) Europäische Musiker in Venedig, Rom, und Neapel. 1650-1750 (in press)

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See detailMétacognition et réussite scolaire : Applications
Frenkel, Stéphanie ULg

in Gireaudeau, Caroline; Chasseigne, Gérard (Eds.) Psychologie, Education et Vie Scolaire (in press)

Ce chapitre présente deux exemples d'application de l'approche métacognitive. D'une part en consultation clinique (Atelier d'Apprentissage, CPLU, ULg). D'autre part en projet de recherche action (EDUCA +).

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See detailClinical sentinel surveillance of equine West Nile fever, Spain
Saegerman, Claude ULg; Alba-Casals, A; Garcia-Bocanegra, I et al

in Transboundary and Emerging Diseases (in press)

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See detailLe contrat d'entreprise
Kohl, Benoît ULg

Book published by Bruylant (in press)

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See detailLeopold August Warnkönig, een voorganger van François Laurent in de universiteiten van Luik en Gent
Gerkens, Jean-François ULg

in Fundamina : A Journal of Legal History (in press), 20(1), 336-348

Warnkönig has been a very important professor during the first decades of university teaching in Belgium (1817-1837). He has taught in all three universities of Belgium and was a brilliant scholar.

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See detailInvestigating word recognition in intercomprehension: methods and findings
Möller, Robert ULg; Zeevaert, Ludger ULg

in Linguistics (in press), 53(2),

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See detailMental Powers in Early Modern Philosophy. British Journal for the History of Philosophy. Special Issue
Boccaccini, Federico ULg; Marmodoro, Anna

Book published by Routledge (in press)

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See detailBrentano and the Primacy of Mental Act
Boccaccini, Federico ULg

in Boccaccini, Federico; Antonelli, Mauro (Eds.) Franz Brentano vol. 2. Intentionality and Philosophy of Mind (in press)

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