References of "Scientific congresses and symposiums"
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See detailmaking the most of the LBTI nulling interferometry observations using a statistical data reduction method
Marion, Lindsay ULg; Mennesson, Bertrand; Defrère, Denis et al

Poster (2014, March 20)

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See detailLe vécu de l'ICSI du côté de l'homme
Barbillon, Adrien ULg; Naziri, Despina ULg

Conference (2014, March 20)

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See detailLe suivi des enfants nés prématurés ou avec un très petit poids de naissance : le projet CAP48
Mostaert, Anne; Nassogne, Marie-Cécile; Vermeylen, Danièle et al

Poster (2014, March 20)

This poster describes the cohort of very preterm and very low birth weight newborns recruted in the "CAP48" project and anaylses the main reasons for cessation of follow-up.

Detailed reference viewed: 36 (3 ULg)
See detailLes enseignants à l'image. Représentations iconographiques et audiovisuelles du mouvement enseignant (1995-1996)
Lanneau, Catherine ULg

Conference (2014, March 20)

Les réformes institutionnelles de 1988-1989 ont transféré aux Communautés les compétences en matière d’enseignement. Pour la Communauté française, cette responsabilisation a très vite rimé avec la ... [more ▼]

Les réformes institutionnelles de 1988-1989 ont transféré aux Communautés les compétences en matière d’enseignement. Pour la Communauté française, cette responsabilisation a très vite rimé avec la nécessité de réaliser d’importantes économies et donc d’importantes réformes structurelles. Une première vague de protestation secoue Bruxelles et la Wallonie en 1990 mais, cinq ans plus tard, un nouveau plan d’économies préparé par la socialiste Laurette Onkelinx, Ministre-Présidente de la Communauté française, en charge notamment de l’Education, donne naissance à un long et douloureux mouvement de protestation. Celui-ci semble matérialiser la rupture entre une base enseignante proche, selon les réseaux, du PS ou du PSC, et un Exécutif au sein duquel ces deux partis fonctionnent en coalition. Réduction des dépenses, suppression de trois mille postes, fusions d’écoles, tous les ingrédients sont réunis pour que la situation soit explosive. Elle va l’être d’autant plus – et cela marquera d’ailleurs durablement les esprits – que certaines manifestations de mécontentement vont s’exprimer avec violence, s’attaquer à des symboliques fortes (la Fête de la Communauté française en septembre 1995, le 1er mai 1996) et perturber la vie privée de la Ministre et de son entourage. Notre contribution s’inscrit dans le volet « images produites ». Elle s’interrogera sur le rôle des images dans la représentation que la presse écrite généraliste a donnée du mouvement enseignant et des enseignants eux-mêmes durant ce conflit. Grâce à certaines archives numérisées, le traitement du mouvement par l’audiovisuel public pourra, lui aussi, être abordé. La photographie de presse, la caricature et le reportage ont-ils contribué à présenter le mouvement enseignant de manière objective et dépassionnée ? Ont-ils au contraire – et jusqu’à quel point ? - intégré les clichés traditionnels véhiculés sur cette catégorie socio-professionnelle (conservatisme, attachement à de supposés « privilèges »…). Quelle image est renvoyée du syndicalisme enseignant ? Comment est mise en scène la relation triangulaire entre grévistes, ministre et public de l’école (parents et élèves) ? Quels sont le poids et le rôle dévolus à chacun ? Quelle est, spécifiquement, le traitement réservé au mouvement par un journal comme La Wallonie ? Comment a-t-il accompagné en images la rupture entre le monde enseignant, la CGSP et le parti socialiste, culminant le 1er mai 1996 ? [less ▲]

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See detailContribution à l'amélioration de l'accès à une eau potable de qualité pour les populations de la région nord du Burkina Faso
Some, Issam; Guel, Boubié; Hantson, Anne-Lise et al

Poster (2014, March 19)

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See detailImpact des matériaux biosourcés sur le climat intérieur : Un outil de calcul flexible à l'échelle de la pièce
Dubois, Samuel ULg; Lebeau, Frédéric ULg

Conference (2014, March 19)

L'impact de l'utilisation de matériaux d'origine végétale sur le climat intérieur, et donc sur le confort des occupants ainsi que la performance énergétique du bâtiment, n'est établi que partiellement ... [more ▼]

L'impact de l'utilisation de matériaux d'origine végétale sur le climat intérieur, et donc sur le confort des occupants ainsi que la performance énergétique du bâtiment, n'est établi que partiellement. Ces produits présentent des propriétés hygroscopiques et capillaires causant des phénomènes spécifiques liés aux changements de phase dynamiques au sein de la matrice poreuse. Les modèles mathématiques utilisés pour étudier leur comportement hygrothermique de manière détaillée sont souvent des modèles de paroi (dits modèles HAM - Heat Air Moisture). Cela sous-tend qu'ils nécessitent d'imposer des conditions aux limites à toutes les frontières de l'élément étudié, et ne permettent donc pas de connaître les flux de chaleur et de masse réels qu'offrent l'assemblage de matériaux vers le volume d'air intérieur. Pour y accéder, il convient d'intégrer ces modèles à la description de bilans thermique et hydrique de zones. Dans cette communication, nous présentons un modèle hygrothermique capable de simuler l'évolution temporelle du climat intérieur d'une ou de plusieurs pièces ("zones thermiques"). Il est composé d'un module HAM basé sur des équations aux dérivées partielles et caractérisant les transferts dans les matériaux de construction et développé au sein de l'environnement numérique COMSOL Multiphysics. Les équations qui le composent sont flexibles et facilement adaptables au cas expérimental modélisé ainsi qu'aux propriétés des matériaux composant les parois. En outre, on y trouve un traitement complet des phénomènes de changement de phase qui prend en compte l'impact de la température sur la capacité de stockage d'humidité du matériau. Ce premier module, est couplé à un outil caractérisant les bilans chaleur/masse au niveau de la zone à l'aide d'équations aux dérivées ordinaires. Le couplage des modèles est effectué au sein de SIMULINK, un outil de MATLAB destiné à l'étude des systèmes dynamiques. Nous appliquons ensuite ce modèle à l'étude d'un mur en ballots de paille séparant une enceinte climatique de grande taille en deux volumes d'air. Les données d'une expérience simple, un choc thermique imposé à un des volumes d'air, sont comparées aux sorties du modèle numérique. [less ▲]

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See detailGoro Gheri, un secrétaire au service de l'art
Miesse, Hélène ULg

Poster (2014, March 19)

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See detailArtificial Abelian gauge potentials induced by dipole-dipole interactions between Rydberg atoms
Cesa, Alexandre ULg; Martin, John ULg

Poster (2014, March 19)

We analyze the influence of dipole-dipole interactions between Rydberg atoms on the generation of Abelian artificial gauge potentials and fields. When two Rydberg atoms are driven by a uniform laser field ... [more ▼]

We analyze the influence of dipole-dipole interactions between Rydberg atoms on the generation of Abelian artificial gauge potentials and fields. When two Rydberg atoms are driven by a uniform laser field, we show that the combined atom-atom and atom-field interactions give rise to nonuniform, artificial gauge potentials. We identify the mechanism responsible for the emergence of these gauge potentials. Analytical expressions for the latter indicate that the strongest artificial magnetic fields are reached in the regime intermediate between the dipole blockade regime and the regime in which the atoms are sufficiently far apart such that atom-light interaction dominates over atom-atom interactions. We discuss the differences and similarities of artificial gauge fields originating from resonant dipole-dipole and van der Waals interactions. We also give an estimation of experimentally attainable artificial magnetic fields resulting from this mechanism and we discuss their detection through the deflection of the atomic motion. [less ▲]

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See detailPrésentation de l'Action de Recherches Concertée EpistolART
Delfosse, Annick ULg; Allart, Dominique ULg; Moreno, Paola ULg et al

Conference (2014, March 19)

Detailed reference viewed: 27 (7 ULg)
See detailInfluence of dipole-dipole interactions decoherence-free states
Damanet, François ULg; Martin, John ULg

Poster (2014, March 18)

Decoherence, known as the consequence of the coupling of any quan- tum system to its environment, causes information loss in the system and represents a major problem in the physical realization of quan ... [more ▼]

Decoherence, known as the consequence of the coupling of any quan- tum system to its environment, causes information loss in the system and represents a major problem in the physical realization of quan- tum computers [1]. Decoherence-Free States (DFS) are considered as a possible solution to this problem. A set of trapped cold atoms placed in a DFS state will be immune against decoherence due to sponta- neous emission. However, because of dipole-dipole interactions between atoms, induced dephasing effects are likely to destroy the coherence and drive the system out of its DFS [1-2]. In this work, we study nu- merically the dynamics of a set of two-level atoms initially in a DFS with respect to dissipative processes by solving the master equation in- cluding both dissipative dynamics and dipole dipole interactions. We focus our attention on the influence of dipolar coupling on the radiated energy rate and coherence of the system as in [3]. In particular, by av- eraging over many realizations of close randomly distributed atomic positions, we show the formation of a superradiant-like pulse and we study its properties as a function of the dipolar coupling strength. [1] D. A. Lidar & K. B. Whaley, Lectures Notes in Phys., Vol. 622, p83-120, Springer (2003). [2] M. Gross & S. Haroche, Physics reports 93, 301-396 (1982). [3] W. Feng, Y. Li & S. -Y. Zhu, arXiv :1302.0957. (2013). [less ▲]

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See detailEstimation de la sédimentation des retenues hydro -agricoles de Kierma et de Wedbila : Méthodologie et résultats obtenus.
Guyon, Francis; Hallot, Eric ULg; Kima, Etienne et al

Conference (2014, March 17)

Detailed reference viewed: 9 (1 ULg)
See detailEvaluation et planification des ressources en eau des petites retenues hydro -agricoles : Application du modèle WEAP aux retenues de Kierma et de Wedbila (Burkina Faso).
Razanamahandry Lovasoa, Christine; Hallot, Eric ULg; Guyon, Francis et al

Conference (2014, March 17)

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See detailEnrichir le lait de vache en équol par la consommation de fourrages prairiaux spécifiques
Franckson, Delphine; Daems, Frédéric ULg; Decruyenaere, Virginie et al

Poster (2014, March 16)

Detailed reference viewed: 6 (1 ULg)
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See detailPRP and tendinopathy, from in vitro to clinical trials
Kaux, Jean-François ULg

Conference (2014, March 15)

Detailed reference viewed: 19 (2 ULg)
See detailRetour au travail après une absence de longue durée
Mairiaux, Philippe ULg

Conference (2014, March 14)

Detailed reference viewed: 13 (0 ULg)
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See detailParallel Computing and Localization Techniques for Faster Power System Dynamic Simulations
Aristidou, Petros ULg; Van Cutsem, Thierry ULg

in Proceedings of Cigre 2014 Belgium Conference (2014, March 13)

Dynamic simulation studies are used to analyze the behavior of power systems after a disturbance has occurred. This type of simulation is essential when the system is operating close to its stability ... [more ▼]

Dynamic simulation studies are used to analyze the behavior of power systems after a disturbance has occurred. This type of simulation is essential when the system is operating close to its stability limits or its behavior is dictated by complex control and protection schemes modifying its trajectory. These simulations can be computationally very demanding, especially if performed over a time interval of several minutes. In this paper, new shared- memory parallel computing techniques to increase the performance of large-scale power system dynamic simulations are described. The algorithms presented achieve this by utilizing the parallel processing resources available in modern, inexpensive, multi-core machines. In addition, the localized response of power systems after a disturbance is exploited to further accelerate simulations without decreasing accuracy. The medium-scale model of a real power system and a realistic large-scale test system have been used for the performance evaluation of the proposed methods. [less ▲]

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See detailUne brochure, trois langues, trois cultures ?
Letawe, Céline ULg; Rasier, Laurent ULg

Conference (2014, March 13)

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See detailWearable respiratory belt for human breathing control
Stoukatch, Serguei ULg; Léonard, Jean; Bellier, Pierre ULg et al

in Conf. Proc. Smart Systems Integration Conf. (SSI2014) (2014, March 12)

We designed and manufactured a working prototype of a wearable respiratory belt. The belt can work as a stand along system or can be embedded into clothes. The system is intended for remote health ... [more ▼]

We designed and manufactured a working prototype of a wearable respiratory belt. The belt can work as a stand along system or can be embedded into clothes. The system is intended for remote health monitoring (particularly to monitor human respiration) such as home healthcare, remote medicine and remote socio-medical assistance as well as to monitor patients. The fully functional prototype proofs the concept that the elongation in the respiratory belt causes by human respiration is accurate enough to measure and to monitor human respiration. [less ▲]

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See detailOpen-source CAT software: R packages and Concerto
Magis, David ULg

Conference (2014, March 12)

Together with the investigation of new or updated CAT procedures, it is of primary importance to ensure development of appropriate, flexible and useful CAT software. Open-source CAT algorithms have been ... [more ▼]

Together with the investigation of new or updated CAT procedures, it is of primary importance to ensure development of appropriate, flexible and useful CAT software. Open-source CAT algorithms have been recently proposed and are offering very promising tools for future practical CAT implementations, though yet under development. After a brief overview of available (commercial) software, I will present and compare the characteristics of some open-source R packages as CAT solutions: catR (Magis, & Raîche, 2012), catIrt (Nydick, 2013) and MAT (Choi, 2011), as well as the R-based software Firestar (Choi, 2009). A more complete description of catR will be given and (depending on time and computer constraints) a short illustrative session will be proposed. Finally, the web platform Concerto (Kosinski & Rust, 2011) will be shortly introduced. References: Choi, S. W. (2009). Firestar: Computerized adaptive testing simulation program for polytomous item response theory models. Applied Psychological Measurement, 33, 644-645. Choi, S. W. (2011). MAT: Multidimensional Adaptive Testing (MAT). R package version 0.1-3. Kosinski, M., & Rust, J. (2011). The development of Concerto: An open source online adaptive testing platform. Paper presented at the International Association for Computerized Adaptive Testing, Pacific Grove, CA. Magis, D., & Raîche, G. (2012). Random generation of response patterns under computerized adaptive testing with the R package catR. Journal of Statistical Software, 48 (8), 1-31. Nydick, S. W. (2013). catIrt: An R package for simulating IRT-based computerized adaptive tests. R package version 0.4-1. [less ▲]

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See detailWhat is the role of the VLTI in the study of particle acceleration in massive binaries?
De Becker, Michaël ULg

Conference (2014, March 12)

Among massive binaries, a fraction is known to accelerate particles up to relativistic energies. The acceleration process is believed to take place in the wind-wind interaction region, and most of these ... [more ▼]

Among massive binaries, a fraction is known to accelerate particles up to relativistic energies. The acceleration process is believed to take place in the wind-wind interaction region, and most of these systems are identified through the production of synchrotron radiation in the radio domain. Considering the crucial role played by binarity in the physics of particle acceleration, tools such as the VLTI appear to be highly relevant to explore the basic properties of this population of objects. A few recent results and prospects for future studies will be briefly presented. [less ▲]

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See detailOn the Identication of Symmetric N-qubit Maximally Entangled States
Baguette, Dorian ULg; Bastin, Thierry ULg; Martin, John ULg

Poster (2014, March 11)

Maximally entangled states can serve as a useful resource in many different contexts. It is therefore important to identify those states. Here we are interested in the identification of maximally ... [more ▼]

Maximally entangled states can serve as a useful resource in many different contexts. It is therefore important to identify those states. Here we are interested in the identification of maximally entangled states in the symmetric subspace of an N-qubit system. By maximally entangled states, we refer to symmetric states characterized by a one qubit reduced density matrix proportional to the identity. These states maximise various entanglement measures [1] such as von Neumann and Meyer-Wallach entropy and are unique up to LU in their SLOCC class [2]. We identify and characterize all maximally entangled symmetric states up to 4 qubits. We provide general conditions for a symmetric state with an arbitrary number of qubits to be maximally entangled and identify families of SLOCC classes which do not contain any maximally entangled states. [1] F. Verstraete, J. Dehaene, B. De Moor, Phys. Rev. A 68, 012103 (2003). [2] G. Gour, N. Wallach, N. J. Phys. 13, 073013 (2011) [less ▲]

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See detailOndes de choc et tendinopathies : expérience clinique du CHU de Liège
Kaux, Jean-François ULg

Conference (2014, March 11)

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Peer Reviewed
See detailBringing regenerating tissues to life: the importance of angiogenesis in tissue engineering
Carlier, Aurélie ULg; Van Gastel, Nick; Geris, Liesbet ULg et al

Poster (2014, March 11)

Detailed reference viewed: 27 (4 ULg)
See detailPerforming Emotions at the Canonization of St. Ignatius and St. Xavier
Delfosse, Annick ULg; Vermeir, Koen; Delbeke, Maarten et al

Conference (2014, March 08)

This paper will approach the celebrations of the canonization of St. Ignatius and St. Xavier in different localities of the Southern Netherlands over the course of 1622 as performances of emotion. We will ... [more ▼]

This paper will approach the celebrations of the canonization of St. Ignatius and St. Xavier in different localities of the Southern Netherlands over the course of 1622 as performances of emotion. We will analyze little known visual and textual testimonials of festivals and theatrical representations in Antwerp, Douai, Brussels, Dunkerque and Leuven to examine which means were used to represent, convey and enhance emotions, which actors were involved, how emotions were meant to address and affect the audience, and to what end emotions were activated. The double canonization of 1622 consecrated the Jesuits as stalwarts of the Roman papacy. In the Southern Netherlands, the celebrations of 1622 were a key moment in confirming the legitimacy of the order by displaying both how it was embedded in the local political and religious arena, and how it mastered the most advanced artistic means to support its mission. After a sketch of the celebrations and their political and religious context, we will analyze how and why emotion was performed in three steps. The sources attach enormous attention to the material, architectural and urban setting of the celebrations, by emphasizing the splendor and artistic sophistication of the events, and by pointing out the prestigious patronage that had accrued around them. We will examine whether and how the sources charged the material context of the celebration with emotion. What was the intended effect of this context on the audience? How did this context enable the performance of emotion in different forms of public display (pageantry, performances, …)? In order to answer this last question, in a second step we will have a closer look at the Triumphus dedicated to St Ignatius and St. Xavier performed in Brussels. We will examine how, in this ensemble, the material context is activated by the movement of the viewer. The description of the Triumphus singles out moments of transition as instances of heightened emotivity, suggesting that emotions are not mobilized by singular details but by overall views that impress themselves when the beholder crosses a treshold. In a third step we will describe the intended effect of the performance of emotions as a sacer horror, the bodily manifestation of religious awe, the organic sensation of respect mixed with fear and wonder felt in the presence of gods or cosmic forces. The performance of emotions, engendered by multiple layers of transformation (of the material context by means of ephemeral architecture, of the views and the experiences of the viewer, and ultimately, of their affective state) was directed at effectuating a lasting change of heart. [less ▲]

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See detailCorsican seagrass detritus: An opportune shelter or a copepod Eldorado?
Mascart, Thibaud ULg; Lepoint, Gilles ULg; Remy, François ULg et al

Poster (2014, March 07)

Seagrass ecosystems are extensive beds of marine flowering plants bordering tropical and temperate coastal regions. They play an important role in maintaining biological productivity and bio-geochemical ... [more ▼]

Seagrass ecosystems are extensive beds of marine flowering plants bordering tropical and temperate coastal regions. They play an important role in maintaining biological productivity and bio-geochemical cycles in the sea and support higher diversity and abundance of fauna in comparison to adjacent non-vegetated areas. The seagrass meadow primary production can be directly consumed through herbivory but the majority of the plant material falls on the sea floor during the autumnal leaf senescence. The leaf litter then degrades within the meadow or accumulates with other micro- and macrophytodetritus to form detritus accumulations on the adjacent non-vegetated sand patches. These exported accumulations are quite dynamic in relation to seafloor geomorphology and local hydrodynamics. Thus, the detritus accumulations are an easily disturbed ephemeral environment with one large influx a year. Consequently the physico-chemical characteristics can change very fast and impact the sheltering capacity and food supply present. Nonetheless, fishes, macrofauna and meiofauna are omnipresent throughout the year. In our study site along the shore of N-W Corsica, Posidonia oceanica seagrass meadows are characterised by substantial detritus accumulations. The present study aimed to analyse the biodiversity of the copepod species communities (Crustacea, Copepoda) in those detritus accumulations. The results showed that the copepod detritus community consisted of a mixture of species that are also found in adjacent habitats (seagrass meadow, sediment, epilithic habitats, water column). Each adjacent habitat is characterised by organisms that are morphologically adapted to the specific features of that habitat. The majority of copepods are epiphytic (order Harpacticoida), that occur typically on seagrass leaves and macroalgae. Other species are planktonic (orders Cyclopoida and Calanoida) and some were benthic (order Harpacticoida), known from the nearby sediment. A minority of the copepod community were parasitic on fish or invertebrate (order Siphonostomatoida). In order to clarify their origin, we assume that passive transport by currents plays a significant role next to the active migration from the anoxic sediments under the detritus. For sure they also reproduce within the detritus packages as we found many nauplii, copepodites and gravid females. The above mentioned suggestions cannot explain such high density of copepods by themselves. Other attraction mechanisms are needed to explain the important amount of planktonic and epiphytic species with good swimming ability, such as higher food accessibility. In the detritus no plant-defence mechanisms are present anymore and a lot of micro-organisms and thus potential food sources are present. Furthermore, the dense detritus package provides shelter and protection from potential predators. Subsequently we may consider the detritus accumulations as a copepod species-specific opportune Eldorado for sheltering, nursing and feeding. [less ▲]

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See detailUsing features of mercury and methylmercury to discriminate contamination profiles between sea bass, Dicentrarchus labrax, populations
Cransveld, Alice ULg; Amouroux, David; Koutrakis, Emmanuil et al

Poster (2014, March 07)

Despite many efforts consented in the last decades, Mercury (Hg) emissions have kept rising worldwide. Currently, anthropogenic inputs dominate Hg emissions to the atmosphere by far, natural releases ... [more ▼]

Despite many efforts consented in the last decades, Mercury (Hg) emissions have kept rising worldwide. Currently, anthropogenic inputs dominate Hg emissions to the atmosphere by far, natural releases accounting only for a 4th of the total. Because Hg has a stable gaseous form (Hg0) with a long residence time in the atmosphere (~1year), both natural and industrially produced Hg can be transported far from point sources. Therefore, many uncertainties remain in our knowledge about Hg biogeochemistry. Our study aims at identifying the different Hg forms found in marine predators in order to discriminate different polluted areas and potential pollution sources. More specifically, we seek to discriminate contaminations of local origins versus contamination of global origins. To achieve this, we are currently studying different sea bass, Dicentrarchus labrax, populations from the Atlantic Ocean and Mediterranean. In muscle, liver, kidney and brain tissues, we analyze total Mercury (THg) and methylmercury (MeHg). We are also testing the discrimination power of Hg's stable isotopes (199Hg, 201Hg and 202Hg). Indeed, recent findings show that Hg isotopes can exhibit both mass-dependent (MDF) and mass-independent fractionation (MIF). This means that Hg isotopes provide two different types of information at once, both on biological cycling of Hg, including bioaccumulation (MDF), and on chemical pathways such as photochemical transformations (MIF). Eventually, we are planning to extend our results with compound specific isotope analysis (CSIA) on the carbon of methylmercury. Preliminary analysis performed on 14 juvenile specimens from the North Sea and the Aegean Sea indicate that THg concentrations are higher in individuals from the North Sea than from Greece. The lack of correlation with size and weight indicate that it is likely linked to a difference in contamination levels between the two areas. MeHg is the predominant form of Hg in muscle, while the same cannot be asserted for liver. Mass dependent isotopic values (δ202Hg), were always higher in muscle than in liver and, for each tissue, values were similar between the two areas. This is probably related to the species distribution and to some internal Hg metabolism. For mass independent isotopic signature (MIF), sea bass from the Aegean Sea had a systematically higher Δ201Hg value than individuals from the North Sea. Thus, mass independent values seem definitely site dependent and might be in agreement with differences in both mercury sources and cycling in the North and Aegean Seas. These preliminary results consequently indicate that Hg isotopes may help to discriminate fish from different areas. This promising outcome must be further confirmed by extending our sampling and will be coupled to other results obtained through CSIA. [less ▲]

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See detailModes intentionnels
Dewalque, Arnaud ULg

Conference (2014, March 07)

Je dresse le bilan de la situation des recherches actuelles en théorie de la perception (entre représentationalisme et relationalisme), et je suggère que la voie d'investigations la plus prometteuse est l ... [more ▼]

Je dresse le bilan de la situation des recherches actuelles en théorie de la perception (entre représentationalisme et relationalisme), et je suggère que la voie d'investigations la plus prometteuse est l'intentionalisme modal. D'après l'intentionalisme modal, un état mental est individualisé par son contenu intentionnel et par son mode intentionnel. En m'appuyant sur la méthode descriptive de Franz Brentano, je propose alors un argument en faveur de cette conception: l'argument de la complétude. [less ▲]

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See detailMicroplastics caught in herring gill rakers: illustration by scanning electron microscopy
Collard, France ULg; Das, Krishna ULg; Parmentier, Eric ULg

Conference (2014, March 07)

Plastics are produced in huge quantity (280 million of tons in 2012) and more than 10% end up in the oceans. It is estimated that between 60 and 80% of all marine debris are plastics. Plastics are ... [more ▼]

Plastics are produced in huge quantity (280 million of tons in 2012) and more than 10% end up in the oceans. It is estimated that between 60 and 80% of all marine debris are plastics. Plastics are persistent and have accumulated in the oceans for several decades. Plastics may adverse wildlife in many ways: they can be ingested by marine vertebrates and cause internal wounds in the digestive tract. Plastics are also vectors of organic pollutants including. Once ingested, plastics may release these pollutants in the organism. Plastics present in the marine environment fragment in small pieces by mechanical stress and UV radiation leading to the so-called microplastics smaller than 5 mm. Little is known about microplastics ingestion and toxicity in planktivorous fish such as the herring, Clupea harengus. Planktivorous fish have gill rakers, which may function as a trap for microplastics. This study aims to describe and characterise microplastics present on gill rakers of the herring, Clupea harengus. Ten gill cavities were sampled in January 2013 in the Channel and the North Sea during a fishery campaign organized by the IFREMER. Gills cavities were placed in a fixating solution until preparation for scanning electron microscopy (SEM). SEM was used in order to detect microplastics which are too small to be observed by a dissection microscope, to compare them with the distance between gill rakers and to characterise the surface and the shape of microplastics. Scanning electron microscopy revealed large variety of microplastics, which lengths ranged from 0.05 to 5mm. Relationship between microplastics length and distance between gill rakers was analysed on the same branchial arch. The present study revealed the presence of microplastics in an edible species of high economic value and raise question about potential impact on the herring and its consumers, including human beings. [less ▲]

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See detailEarly neuropsychological detection of Alzheimer's disease
Bastin, Christine ULg

Conference (2014, March 06)

Considering that brain pathology due to Alzheimer’s disease starts many years before the clinical symptoms become evident, subtle cognitive changes may exist already in the predementia phase. Different ... [more ▼]

Considering that brain pathology due to Alzheimer’s disease starts many years before the clinical symptoms become evident, subtle cognitive changes may exist already in the predementia phase. Different approaches have been used to detect initial cognitive impairments indicative of Alzheimer’s disease. One approach is the assessment of the predictive power of neuropsychological tools in characterizing patients with stable mild cognitive impairment (MCI) versus MCI patients who subsequently develop Alzheimer’s disease. Another approach is the longitudinal evaluation of large cohorts of older adults in population-based studies. Findings from several studies suggest that a memory test that ensures deep encoding of information and assesses retrieval with free as well as cued recall is a useful tool to distinguish patients at an early stage of Alzheimer disease from MCI non-converters. Impaired semantic memory has also been proposed as a neuropsychological marker of predementia Alzheimer’s disease. Beyond the memory domain, category verbal fluency has been shown to predict progression to Alzheimer’s disease. Moreover, combining neuropsychological scores of memory and executive functions and neuroimaging data allows a better discrimination between stable MCI and converters than neuroimaging data alone. Altogether, it is possible to detect cognitive changes that are predictive of the typical form of probable Alzheimer’s disease already in the predementia stage. Such at risk people are thought to be the best target for therapeutic interventions. [less ▲]

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See detailEquations fantaisistes : l'argent comme ressort burlesque dans l'œuvre de Pierre La Police
Belloi, Livio ULg

Conference (2014, March 06)

Conçue comme une vaste parodie du discours médiatique en général et de la presse quotidienne en particulier, la série "Véridique !" (Cornélius, 1999-2002) du dessinateur français Pierre La Police met ... [more ▼]

Conçue comme une vaste parodie du discours médiatique en général et de la presse quotidienne en particulier, la série "Véridique !" (Cornélius, 1999-2002) du dessinateur français Pierre La Police met volontiers en scène des questions ou des rapports d’argent. Le plus souvent lié à la sphère politique, le thème de l’argent autorise l’auteur à jeter un regard narquois et particulièrement acéré sur des événements qui firent grand bruit dans la France des années 1990 (l’affaire Roland Dumas, le scandale de l’ARC, l’affaire des emplois fictifs à la ville de Paris, etc.). Ma communication étudie au plus près les mises en scène de l’argent dans l’œuvre de Pierre La Police et s'efforce de porter au jour les véritables équations mises au point à cet égard par l’auteur. Toutes à leur manière, ces équations concourent à faire du thème de l’argent un ressort burlesque à part entière ; elles participent également d’une esthétique générale de la distorsion et de l’approximation, qui est comme la marque de fabrique de Pierre La Police. [less ▲]

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See detailIntentionalisme et représentationalisme de Brentano à Crane
Boccaccini, Federico ULg

Conference (2014, March 06)

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See detailChemical Hydrolysis of Fagus sylvatica Wood: Dilute Acid vs. Alkaline Treatment
Miazek, Krystian ULg; Goffin, Dorothée ULg; Richel, Aurore ULg

Poster (2014, March 05)

Lignocellulosic biomass, found in a large variety of plants such as coniferous trees (Softwood), broad leaved trees (Hardwood), grasses and agricultural or food residues, is the most abundant source of ... [more ▼]

Lignocellulosic biomass, found in a large variety of plants such as coniferous trees (Softwood), broad leaved trees (Hardwood), grasses and agricultural or food residues, is the most abundant source of molecules required for production of biofuels and high value - added products. Lignocellulose is composed of three polymers: cellulose, hemicellulose and lignin. Cellulose is a non-branched polymer consisting of glucoses (hexoses). Hemicellulose is a complex carbohydrate containing pentoses (mainly xyloses in the case of Hardwood, grasses and agricultural wastes) or hexoses (usually mannoses in the case of Softwood) as the main sugars. Lignin is a biopolymer with aromatic alcohols as basic monomeric units. Cellulose chains are arranged in bundles and interlinked with hemicellulose. Lignin is cross-linked with hemicellulose and occupies space between cellulose bundles. Due to complex polymeric structure, lignocellulosic materials are resistant to hydrolysis. A number of treatment methods (mechanical, chemical, biochemical) is implemented to successfully hydrolyse lignocellulose. Amongst chemical methods harnessed to break lignocellulose structure, dilute acid and alkaline treatments are commonly mentioned, as the most efficient ones. The objective of this study was to evaluate the effect of dilute acid and alkaline treatment on hydrolysis rate of polymeric components in Fagus sylvatica wood. Fagus sylvatica also known as common beech is a broad leaved, deciduous tree that belongs to the family of Fagaceae, widely spread in Europe. Beech wood was determined to contain 48 % glucose, 18 % xylose and 20 % Klason lignin in its dry material. Results of this study showed that 1 h hydrolysis at 100 °C with the use of 3 % H2SO4 resulted in 71 % removal of xylose and 4 % removal of glucose with Klason lignin remained intact. Additionally, the presence of sugar degradation products: 2 - furfural and hydroxymethylfurfural was detected in dilute acid hydrolysate. Release of 2 - furfural and hydroxymethylfurfural from beech wood was determined as 0.03 % and 0.1 %, respectively. On the other hand, 1 h hydrolysis at 100 °C with the use of 7 % NaOH caused 59 % xylose removal and 11 % removal of Klason lignin with no effect on glucose. Dilute acid hydrolysis proved to be more efficient in removing xylose, but alkaline hydrolysis additionally showed to remove Klason lignin. [less ▲]

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See detailSome Interesting Sources of Plant Seed Oil
Paul, Aman ULg; Danthine, Sabine ULg; Blecker, Christophe ULg et al

Poster (2014, March 05)

There is a growing realization worldwide that biodiversity is fundamental to agricultural production and food security, as well as a valuable ingredient of environmental conservation. Flowering strips ... [more ▼]

There is a growing realization worldwide that biodiversity is fundamental to agricultural production and food security, as well as a valuable ingredient of environmental conservation. Flowering strips around the border of the crops serves as an important function to improve the biodiversity, besides this they play a major role in the ruminant nutrition and serve as a source of numerous beneficial compounds. It is well known that seeds store their food reserves for next generation mainly in the form of lipids; some of the seeds from these flowering strips could be an interesting source of lipids. These seed oils could play important role in food, pharmaceutical, cosmetics and other industries. The extraction of seed oil from four such plant species in Belgium namely Oregano (Origanum vulgare), Yellow Bedstraw (Galium verum), Common Self-heal (Prunella vulgaris) & Purple loosestrife (Lythrum salicaria) was carried out. Extraction was done by a cold extraction technique using chloroform/methanol in 2:1 ratio as solvent. Amount of oil extracted from Oregano, Yellow Bedstraw, Common Self-heal and Purple loosestrife was 22.58±0.03 %, 3.28±0.01 %, 14.84±0.12 % & 20.32±0.15 %. The fatty acid profiles of these four species were determined by gas chromatography (using methyl esters of their fatty acids); Oleic acid and Linoleic acid were found in all the four species, Gamma-linolenic acid was found in Purple loosestrife & Alpha-linolenic acid was found in Oregano and Common Self-heal plant species. Thermal behaviour of these four plant seed oils were analyzed using Differential Scanning Calorimetry (DSC), while some other physicochemical properties of the seed oils were also analyzed. These plant seed oils can be of great commercial importance. [less ▲]

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See detailA vision-based autonomous inter-row weeder
Krishna Moorthy Parvathi, Sruthi Moorthy ULg; Detry, Renaud ULg; Boigelot, Bernard ULg et al

Conference (2014, March 05)

Autonomous robotic weed destruction plays a significant role in crop production as it automates one of the few unmechanized and drudging tasks of agriculture i.e. manual weed destruction. Robotic ... [more ▼]

Autonomous robotic weed destruction plays a significant role in crop production as it automates one of the few unmechanized and drudging tasks of agriculture i.e. manual weed destruction. Robotic technology also contributes to long-term sustainability with both economic and environmental benefits, by minimising the current dependency on chemicals. The aim of this study is to design a small low-cost versatile robot allowing the destruction of weeds that lie between the crop rows by navigating in the field autonomously and using a minimum of a priori information of the field. For the robot to navigate autonomously, necessary and sufficient information can be supplied by a machine vision system. One important issue with the application of machine vision is to develop a system that recognises the crop rows accurately and robustly which is tolerant to problems such as crops at varying growth stages, poor illumination conditions, missing crops, high weed pressure, etc. Aiming at accurate and robust real-time guidance of autonomous robot through the field, the plethora of image processing algorithms like Ostu’s threshold method and hough transform will be explored for two main processes namely the image segmentation and crop row detection respectively. In order to overcome the issue of large variabilities encountered in agriculture such as varying weather conditions, intelligent stochastic data fusion and machine learning algorithms will be used to combine data from heterogeneous sensors. Besides crop row detection, other major challenges foreseen are: mapping the unknown geometry of the field, high-level planning of efficient and complete coverage of the field, controlling the low-level op- erations of the robot, and ensuring security. Specialised sensors such as GPS will be considered to generate the map of the field enabling Simultaneous Localisation And Mapping (SLAM) in real time on a mobile platform. The generated map will be exploited along with the sensorial in- formation from crop row detection to efficiently plan and execute the guidance of the robot au- tonomously in the field, thereby enabling weed elimination. [less ▲]

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See detailWildflower strips: a help for crop protection ?
Hatt, Séverin ULg; Uyttenbroeck, Roel ULg; Bodson, Bernard ULg et al

Conference (2014, March 05)

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See detailWildflower strips: a help for crop protection ?
Hatt, Séverin ULg; Uyttenbroeck, Roel ULg; Bodson, Bernard ULg et al

Poster (2014, March 05)

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See detailUsing active and passive acoustics to assess O2 production of a Posidonia oceanica meadow
Felisberto, P; Zabel, F; Rodriguez, O et al

Poster (2014, March 04)

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See detailHow do we perceive vocal pitch accuracy during singing?
Larrouy, Pauline ULg; Pfordresher, Peter Q

Conference (2014, March 03)

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See detailLand-fast sea ice of McMurdo Sound as a source of bio-essential trace metals for primary productivity in the Ross Sea, Antarctica
Schoemann, V.; de Jong, J.T.M.; Tison, J.L. et al

Conference (2014, March)

Iron (Fe) is an essential micronutrient. Its low abundance limits primary productivity in more than 30% of the oceans, including the Southern Ocean, and has a crucial impact on the biogeochemical cycles ... [more ▼]

Iron (Fe) is an essential micronutrient. Its low abundance limits primary productivity in more than 30% of the oceans, including the Southern Ocean, and has a crucial impact on the biogeochemical cycles of carbon and other elements with ultimate influence on the Earth climate system. Other trace metals, like Mn, Zn, Co and Cu are also required for microorganisms cell metabolism and may be (co-) limiting. Previous data on dissolved and particulate Fe concentration data showed that Fe is 10-100 times more concentrated in the sea ice than in underlying seawater and that sea ice melt can deliver up to 70% of the daily Fe supply to the surface waters. According to budget estimates in East Antarctica and in the Weddell Sea, accumulated Fe would largely derive from the underlying seawater rather than from atmospheric inputs. Most of the available data of trace metals in the sea ice concern pack ice and Fe. Only very scarce data exist on land-fast ice and on other trace metal concentrations. In this presentation, the general objective is to assess the role of land-fast ice as a source of Fe and other bio-essential trace metals (e.g. Mn, Zn, Cu, Mo, Cd), its impact on primary productivity and on the biological pump. Samples of sea ice, brines and seawater as well as dusts samples have been collected during the land-based sampling program YROSIAE at Cape Evans (Scott Base, McMurdo Sound, Ross Sea, Antarctica) from Nov 2011 to Dec 2011 and from Aug 2012 to Dec 2012. Dissolved and particulate trace metals concentrations have been measured by a recently developed method, which combines multiple element isotope dilution with preconcentration using the Nobias Chelate PA1 resin and ICP-MS analysis. Concentrations of trace metals in snow collected during the present study are one to up to five orders of magnitude higher than the concentrations previously observed in snow from East Antarctica, showing a much stronger dust input of these metals in McMurdo Sound. When comparing the concentrations obtained in the under-ice seawater with those obtained in the snow at McMurdo Sound, concentrations of Fe, Al, Mn, Co are much lower, whereas concentrations of Cu, Zn and Pb are similar and the concentrations of Ni, Mo and Cd are higher. Inventories of these trace metals in the land-fast sea ice give insights on its role as a source of bio-essential trace metal for the fuelling of the seasonal Ross Sea bloom. Other sources of these trace metals will be addressed and compared. [less ▲]

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See detailRupture et repli sur soi. À propos de quelques traits posturaux de Rousseau dans sa correspondance entre 1762 et 1765
Biquet, Stéphanie ULg

in Francalanza, Eric (Ed.) Actes du colloque international "Rousseau en toutes lettres", Brest 22-24 mars 2012 (2014, March)

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See detailLearning to Learn: Assessment of Metacognitive competencies
Frenkel, Stéphanie ULg; Nobile, Debora ULg

in IATED (Ed.) INTED2014 Proceedings (2014, March)

Numerous students are having school difficulties linked to the way they learn. Some authors speak of a “metacognitive deficit”. We refer to a “sleeping potential” instead (Frenkel, 2013, in press; Frenkel ... [more ▼]

Numerous students are having school difficulties linked to the way they learn. Some authors speak of a “metacognitive deficit”. We refer to a “sleeping potential” instead (Frenkel, 2013, in press; Frenkel & Deforge, in press; Frenkel & Nobile, 2013). Be it psychologists, teachers or parents, all wish to develop their skills in order to help these students. This is the case in primary and secondary school. Metacognitive abilities play a central role in learning (e.g., Frenkel & Deforge, in press; Giasson, 2001; Grangeat, 1997; Hessels & Hessels-Schlatter, 2010b; Lumbelli, 2003; Poissant, Poëllhuber & Falardeau, 1994; Rozencwajg, 2003; Veenman, Kok & Blöte, 2005) and thus in successful school learning (Büchel, 2013a, 2013b; Van der Stel & Veenman, 2010; Wang, Haertel & Walberg, 1994). However, studying them requires that we clarify what is meant by “metacognition” and “metacognitive abilities”. In this framework, we developed the EDUCA + project which is intended to provide possible solutions. EDUCA + is based on wide field experience. Its theoretical background is based on a substantial review of the literature. Its objective is to increase the expertise of “front line” field workers by developing specific products such as tools, training courses, services, and a website (Frenkel, in press). This will notably enable them to develop their expertise, detect « sleeping » potential, diagnose, give advice when necessary, intervene (prevention and remediation) and use the tools efficiently. Two types of tools are being designed. On the one hand, assessment tools (tests allowing to put forward the learner’s strengths and weaknesses as well as the scope of his/her “sleeping potential”). On the other hand, intervention tools (short prevention vs. remediation programs). This also includes training courses and services. The creation of a website also aims to reinforce the actions of EDUCA + (personalized access depending on the internaut’s profile: students, parents, professionals). The aim of this paper is to present this research project and its main theoretical background. [less ▲]

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See detailModeling reaction-limited Ostwald ripening of supported Ni catalysts in presence of CO: the role of particle size distribution
Gommes, Cédric ULg; Munnik, Peter; de Jongh, Petra et al

Poster (2014, March)

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See detailDissection artérielle cérébrale chez l'enfant
BARREA, Christophe ULg; RAMAEKERS, Vincent ULg; OTTO, Bernard ULg et al

Conference (2014, March)

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See detailSubspace and maximum likelihood identification of nonlinear mechanical systems
Noël, Jean-Philippe ULg; Schoukens, Johan; Kerschen, Gaëtan ULg

Conference (2014, March)

The present work focuses on a recent nonlinear generalisation of the existing (linear) frequency-domain, discrete-time subspace methods applicable to mechanical systems. The proposed estimator, termed ... [more ▼]

The present work focuses on a recent nonlinear generalisation of the existing (linear) frequency-domain, discrete-time subspace methods applicable to mechanical systems. The proposed estimator, termed FNSI method, is interesting because it benefits from the numerical robustness and efficacy of subspace algorithms, while maintaining an acceptable computational burden. However, it derives estimates of the model parameters, namely the modal properties of the underlying linear system and the coefficients of the nonlinearities, based on deterministic arguments and one has thus no guarantee that the estimates still behave well in the presence of disturbing noise. A possible alternative is to embed the identification problem in a stochastic framework through the minimisation of a well-chosen cost function incorporating noise information. In particular, the maximum likelihood cost function is attractive because it yields estimates of the model parameters with optimal stochastic properties, and simplifies to a weighted least-squares expression in the frequency domain. However, the maximum likelihood suffers from issues typically encountered in optimisation problems, especially related to initialisation. The contribution of this work lies in the utilisation of the model parameter estimates provided by the FNSI method to serve as starting values for the minimisation of the maximum likelihood cost function. This initialisation strategy possesses the important advantage that the FNSI method generates a fully nonlinear model of the system under test, while classical approaches commonly use a linear model of the nonlinear system as starting point. This ensures that the resulting maximum likelihood model performs at least as good as the nonlinear subspace model. The complete methodology is demonstrated using experimental data measured on the Silverbox benchmark, an electronic circuit emulating the behaviour of a mechanical system with cubic nonlinearity. [less ▲]

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See detailAlkaline Primary Melts from the Primitive Mantle of Mars
Collinet, Max ULg; Médard, Etienne; Vander Auwera, Jacqueline ULg et al

Poster (2014, March)

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See detailReliability and validity of the Quality of Life Systemic Inventory for Children (QLSI-C): Preliminary result of a modular assessment tool of quality of life using e-Health technologies
Toucheque, Malorie ULg; Etienne, Anne-Marie ULg

Poster (2014, March)

Objective: Use of generic versus specific tools in psychological assessment is a controversial issue. Generic instruments can be used to measure QOL for numerous chronic illnesses; however, they may not ... [more ▼]

Objective: Use of generic versus specific tools in psychological assessment is a controversial issue. Generic instruments can be used to measure QOL for numerous chronic illnesses; however, they may not be sensitive to particular aspects of the disease. Unfortunately, disease-specific measures cannot be used to compare results across diseases or conditions. The QLSI-C is an assessment tool that uses a modular approach developed to overcome these shortcomings. QLSI-C was devised as a generic scale to be integrated with disease specific modules. The purpose of this study is to report on reliability and validity of the QLSI-C generic scale and the cystic fibrosis (CF)-specific module. Methods: QLSI-C was administered to 20 children with CF and 20 healthy children (ages 8-12 years) in Belgium. Internal consistency was assessed using Cronbach’s coefficient. Validity of the QLSI-C was measured using the known-groups method, i.e., analysis of variance (ANOVA) to distinguish between healthy children and children with CF. To examine the validity of the QLSI-C, correlations were calculated between the generic scale and CF-specific module. Results: Internal consistency for the QLSI-C generic scale with the CF-specific module was good ( =.82). ANOVA results revealed a significant difference between CF and healthy children for the QOL score (p=.005), with higher average scores (i.e., lower QoL) for CF children (M=4.35) than healthy children (M=1.25). Correlations between QoL scores on the generic scale and CF-specific module demonstrated medium effect size (r=0.47; p=.04). Conclusions: To date, three specific modules are available for the QLSI-C: (1) cancer; (2) asthma; (3) cystic fibrosis. Originality of this tool is strengthened by use of e-Health technologies (i.e., iPad app for administering the QLSI-C). Satisfactory psychometric properties and state-of-the-art use of technology suggests that the QLSI-C has potential utility for use in clinical trials, research, and clinical practice. [less ▲]

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See detailDimethyl sulfide and dimethylsulfoniopropionate profiles in sea ice during winter in the Weddell Sea
Uhlig, C.; Tison, J.-L.; Rintala, J. et al

Conference (2014, March)

This study presents profiles of the organic sulphur components dimethylsulfide (DMS) and dimethylsulfoniopropionate (DMSP) in sea ice cores collected during the AWECS (Antarctic Winter Ecosytem Climate ... [more ▼]

This study presents profiles of the organic sulphur components dimethylsulfide (DMS) and dimethylsulfoniopropionate (DMSP) in sea ice cores collected during the AWECS (Antarctic Winter Ecosytem Climate Study) cruise on RV Polarstern (ANT29-6) in the Weddell Sea. DMS is a semi-volatile sulfur component and under discussion to be climate active, as its oxidation products might act as cloud condensation nuclei - thus cooling the atmosphere. It is produced by enzymatic cleavage of the precursor DMSP, which is synthesized by various types of phytoplankton and serves for example as compatible solute and cryoprotectant. Due to the physico-chemical conditions given, i.e. the high salinity and the icy matrix, sea ice as habitat favors production of high levels of DMSP by the inhabiting microalgae. DMSP and DMS are frequently found in high concentrations in sea ice during spring and summer. The aim of this study was to investigate DMS(P) levels in winter sea ice as data for the winter season is yet scarce, but is of importance for global budgeting. Preliminary results of our study show that DMS(P) production in sea ice in the Weddell Sea is also significant during winter. This stands in contrast to previous measurements in Arctic winter sea ice (CFL-IPY cruise in the Circumpolar Flaw Lead Polynya), where DMS(P) concentrations were very low. Possible explanations for the differences between DMS(P) levels in the Arctic and Antarctic might be the different snow cover and thus insulation, light regimes and also microbial community structure within the ice. DMS(P) levels were generally correlated with chlorophyll a concentrations, although the details are complex and seem to be influenced by species composition and species specific DMSP/Chla ratios. The DMS profiles mirrored the permeability of the sea ice following DMSP in the impermeable areas while showing losses to the ice surface and ice-water interface in the more permeable regions. Winter DMS(P) profiles are furthermore compared to data collected during the following spring cruise of RV Polarstern (ANT29-7) in the Weddell Sea. [less ▲]

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See detailEmbodying the divine: herms in Greek vase-painting
Collard, Hélène ULg

Conference (2014, March)

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See detailSea ice CO2 flux in the Southern Ocean during mid-winter and early spring
Nomura, D.; Delille, Bruno ULg; Dieckmann, G.S. et al

Conference (2014, March)

There seems little doubt that sea ice is permeable to CO2 and other gases although air–sea ice gas flux is more or less inhibited at a brine volume fraction of less than 5% representing the threshold for ... [more ▼]

There seems little doubt that sea ice is permeable to CO2 and other gases although air–sea ice gas flux is more or less inhibited at a brine volume fraction of less than 5% representing the threshold for fluid permeability of sea ice. Generally, air–sea ice CO2 flux is at its minimum in winter due to low sea ice temperatures and consequently reduced permeability despite the fact the partial pressure of CO2 in sea ice is usually high at that time and sea ice has therefore the potential to release CO2 to the atmosphere. Here, we present first evidence that snow laden Antarctic sea ice can act as source for atmospheric CO2 even during mid-winter and early spring. During a mid-winter cruise to the Weddell Sea (AWECS, 2013) and an early spring cruise off east Antarctica (SIPEX-2, 2012), due to thick insulating snow covers, the bottom of the snow and the surface of the sea ice were relatively warm (>–10°C) even though air temperature was sometimes below –30°C. In addition, in both areas, sea ice was characterized by high bulk-salinities, resulting in brine volume fractions that are generally higher than 5%. Automatic “open-closed” chamber measurements indicated positive CO2 fluxes of up to +2.5 mmol C m–2 day–1, illustrating that sea ice acted as a source of atmospheric CO2. Higher fluxes were measured at bare ice surfaces after removing the snow. However, generally low snow densities (mean: 339 kg m–3), indicating a permeable snow cover, facilitated degassing of CO2 at the snow-air interface. Our results therefore suggest that even in the winter and early spring, Antarctic sea ice can act as CO2 source for the atmosphere, particularly in areas with a thick insulating snow cover. [less ▲]

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See detailShergottites: Partial Melts of a Depleted Martian Mantle
Médard, Etienne; Collinet, Max ULg

Poster (2014, March)

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See detailYear Round survey of Ocean-Sea Ice-Air Exchanges – the YROSIAE survey
Delille, Bruno ULg; Haskell, T.; Champenois, Willy ULg et al

Conference (2014, March)

YROSIAE survey aimed to carry out a year-round survey of land-fast sea ice focusing on the study of sea ice physics and biogeochemistry in order to a) better understand and budget exchanges of energy and ... [more ▼]

YROSIAE survey aimed to carry out a year-round survey of land-fast sea ice focusing on the study of sea ice physics and biogeochemistry in order to a) better understand and budget exchanges of energy and matter across the ocean-sea ice-atmosphere interfaces during sea ice growth and decay and b) quantify their potential impact on fluxes of climate gases (CO2, DMS, CH4, N2O) to the atmosphere and on carbon and macro- nutrients and micro-nutrients export to the ocean. Ice cores, sea water, brines and exported material were collected at regular intervals about 1 km off cape Evans from November 2011 to December 2011 and from September 2012 to December 2012 in trace-metal clean conditions. Samples are processed to characterize both the vertical distribution and temporal changes of climate gases (CO2, DMS, CH4, N2O), CO2-related parameters (dissolved inorganic carbon, total alkalinity and CaCO3 amount), physical parameters (salinity, temperature, texture, 18O), biogeochemical parameters (macro-nutrients, particulate and dissolved organic carbon, δ13C, δ30Si and δ15N, micro-nutrients - including iron) and biological parameters ( chlorophyll a, primary production within sea ice derived from O2:Ar and O2:N ratios, autotrophic species determination, bacterial cell counts a.s.o.). In addition, we deployed a micro-meterological tower and automatic chambers to measure air-ice CO2 fluxes. Continuous measurements of ice temperature and ice accretion or melting, both at the ice-ocean and the ice-atmosphere interfaces were provided by an “Ice-T” ice mass balance buoy. Sediment traps collected particles below the ice between 10 and 70 m, while dust collectors provided a record of a full suite of trace metal and dust at different levels above the ground. We will present the aims, overall approach and sampling strategy of the YROSIAE survey. In addition we will also discuss CO2 dynamics within the ice and present temporal air-ice CO2 fluxes over the year. We will provide a first budget of air-ice CO2 fluxes during ice growth for Antarctica sea ice and discuss the impact of the snow cover on air-ice CO2 fluxes. [less ▲]

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See detailPrognostic value of FDG PET/CT in liver transplantation for hepatocarcinoma
DETRY, Olivier ULg; Govaerts, L; BLETARD, Noëlla ULg et al

in Acta Gastro-Enterologica Belgica (2014, March), 77(1), 08

AIM : FDG uptake has been shown to predict the outcome in large series of patients with hepatocarcinoma (HCC) in Asia, but few data are available regarding European populations. Our aim was to evaluate ... [more ▼]

AIM : FDG uptake has been shown to predict the outcome in large series of patients with hepatocarcinoma (HCC) in Asia, but few data are available regarding European populations. Our aim was to evaluate the prognostic value of pretreatment FDG PET-CT in patients treated by liver transplantation. Methods: We retrospectively analyzed the data of 27 patients (24 M and 3 W, mean age 58 ± 9 years). The mean follow-up was 26 ± 18 months (min 1 month, max 66 months). All patients had an FDG PET-CT before the transplantation. The FDG PET/CT was performed according to a standard clinical protocol: 4 MBqFDG/kg body weight, uptake 60 min., low-dose non-enhanced CT. We measured the SUVmax and SUVmean of the tumor and the normal liver. The tumor/liver activity ratios (RSUVmax and RSUVmean) were tested as prognostic factors and compared to the following conventional prognostic factors: MILAN, CLIP, OKUDA, TNM stage, alphafoetoprotein level, portal thrombosis, size of the largest nodule, tumor differentiation, microvascular invasion, underlying cirrhosis and liver function. Results : The DFS was 87.2% at 1y and 72.1% at 3y. The OS was 85.2% at 1y and 80.7% at 3y. According to an univariate Cox model, RSUVmax, RSUVmean and healthy liver were predictors of DFS and RSUVmax, RSUVmean, size of the largest nodule, CLIP, liver involvement>50%, and healthy liver predicted the OS. According to a multivariate Cox model, only RSUVmax predicted DFS and RSUVmax and liver involvement>50% predicted OS. An ROC analysis of the ratios showed that the 1.15 cut-off for RSUVmax was best for predicting both the DFS (Cox regression:HR 14.4, p=0.02) and OS (HR 5.6, p=0.049). The Kaplan-Meier curves and Logrank tests confirmed those results. Even though the MILAN criteria alone were not predictive, it is worth noting that none of the patients outside the MILAN criteria and with RSUVmax<1.15 relapsed. Conclusions: The RSUVmax is a strong prognostic factor for recurrence and death in patients with HCC treated by liver transplantation with a cut-off value of 1,15. further prospective studies should test whether the metabolic index should be systematically included in the preoperative assessment. [less ▲]

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See detailFactors driving pCO2 dynamics in sea ice during a large-scale ice tank experiment
Zhou, Jiayun ULg; Delille, Bruno ULg; Tison, J.-L. et al

Conference (2014, March)

According to previous studies, pCO2 fluxes measured over Arctic sea ice are higher than those measured over Antarctic sea ice. We hypothesized that this was due to enhanced respiration in Arctic sea ice ... [more ▼]

According to previous studies, pCO2 fluxes measured over Arctic sea ice are higher than those measured over Antarctic sea ice. We hypothesized that this was due to enhanced respiration in Arctic sea ice, as a consequence of higher riverine inputs of dissolved organic carbon (DOC) into Arctic seawater. We tested this hypothesis during the Interice V experiment at the HSVA (Hamburg) environmental test basin facility. We reproduced the growth and decay cycle of sea ice in replicate mesocosms (1 m3) filled with North Sea water (NSW series), and compared these with another series of mesocosms to which humic-rich river water had been added (10%) to increase the DOC concentration (R series). Primary producers were excluded from the experiment. The evolution of the temperature, salinity, DOC, pCO2 and bacterial biomass and production were measured in ice sampled at regular intervals throughout the experiment, as well as in the under-ice water. In addition, ice-air pCO2 fluxes were continuously monitored over both NSW and R mesocosms. pCO2 values in ice were higher in the R ice than in the NSW ice. This is attributed to the DOC content and bacterial respiration, rather than to the ice physical properties (i.e., ice permeability constrained by the ice temperature and salinity). Indeed, R ice had higher DOC content and bacterial production than the NSW ice while both showed similar physical properties. The evolution of the ice-air pCO2 fluxes was consistent with the evolution of pCO2 in ice. The fluxes were, as expected, positive (from sea ice to the atmosphere) during ice growth and negative (from the atmosphere to the ice) during ice melt. [less ▲]

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See detailRèglement Successions (650/2012) - aperçu général pour la planification successorale
Wautelet, Patrick ULg

Conference (2014, March)

Cette présentation donne un aperçu général des principes sur lesquel le Règlement 650/2012 est fondé, avec une attention particulière consacrée à l'impact du Règlement sur la pratique de la planification ... [more ▼]

Cette présentation donne un aperçu général des principes sur lesquel le Règlement 650/2012 est fondé, avec une attention particulière consacrée à l'impact du Règlement sur la pratique de la planification successorale [less ▲]

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See detailOrganized proteomic heterogeneity in colorectal liver metastases and implications for therapies
Turtoi, Andrei ULg; Blomme, A; Debois, Delphine ULg et al

in Acta Gastro-Enterologica Belgica (2014, March), 77(1), 07

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See detailLearning to learn: Assessment of metacognitive competencies
Frenkel, Stéphanie ULg; Nobile, Debora ULg

Poster (2014, March)

Numerous students are having school difficulties linked to the way they learn. Some authors speak of a “metacognitive deficit”. We refer to a “sleeping potential” instead (Frenkel, 2013, in press; Frenkel ... [more ▼]

Numerous students are having school difficulties linked to the way they learn. Some authors speak of a “metacognitive deficit”. We refer to a “sleeping potential” instead (Frenkel, 2013, in press; Frenkel & Deforge, in press; Frenkel & Nobile, 2013). Be it psychologists, teachers or parents, all wish to develop their skills in order to help these students. This is the case in primary and secondary school. Metacognitive abilities play a central role in learning (e.g., Frenkel & Deforge, in press; Giasson, 2001; Grangeat, 1997; Hessels & Hessels-Schlatter, 2010b; Lumbelli, 2003; Poissant, Poëllhuber & Falardeau, 1994; Rozencwajg, 2003; Veenman, Kok & Blöte, 2005) and thus in successful school learning (Büchel, 2013a, 2013b; Van der Stel & Veenman, 2010; Wang, Haertel & Walberg, 1994). However, studying them requires that we clarify what is meant by “metacognition” and “metacognitive abilities”. In this framework, we developed the EDUCA + project which is intended to provide possible solutions. EDUCA + is based on wide field experience. Its theoretical background is based on a substantial review of the literature. Its objective is to increase the expertise of “front line” field workers by developing specific products such as tools, training courses, services, and a website (Frenkel, in press). This will notably enable them to develop their expertise, detect « sleeping » potential, diagnose, give advice when necessary, intervene (prevention and remediation) and use the tools efficiently. Two types of tools are being designed. On the one hand, assessment tools (tests allowing to put forward the learner’s strengths and weaknesses as well as the scope of his/her “sleeping potential”). On the other hand, intervention tools (short prevention vs. remediation programs). This also includes training courses and services. The creation of a website also aims to reinforce the actions of EDUCA + (personalized access depending on the internaut’s profile: students, parents, professionals). The aim of this paper is to present this research project and its main theoretical background. Keywords: Metacognition, School, Student, Potential, Dynamic Assessment. [less ▲]

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See detailNew insights for an old topic: seagrasses as bioindicators of coastal trace element pollution
Richir, Jonathan ULg; Lejeune, Pierre; Gobert, Sylvie ULg

in ARGYRO ZENETOS, ZENETOS (Ed.) Mediterranean Marine Science (2014, March)

The marine magnoliophyte Posidonia oceanica (L.) Delile has been widely used since the mid-70th to biomonitor the coastal pollution of the Mediterranean in Cr, Ni, Cu, Zn, Cd, Pb and/or Fe. In contrast ... [more ▼]

The marine magnoliophyte Posidonia oceanica (L.) Delile has been widely used since the mid-70th to biomonitor the coastal pollution of the Mediterranean in Cr, Ni, Cu, Zn, Cd, Pb and/or Fe. In contrast, other trace elements (TEs) like As, V, Ag, Be, Al, Mn, Co, Se, Mo, Sn, Sb and Bi, many of them categorized as TEs of environmental emerging concern, have been subject to nearly no ecotoxicological survey with that species. It has been shown that the French Mediterranean littoral was submitted to local, diffuse and/or chronic contaminations both by TEs broadly or little biomonitored with P. oceanica; high TE levels could further be linked to specific anthropic activities such as agriculture (Mo), mining (Cr, Sb, Zn), industries (As), storage and refinement of oil products (V, Pb) or presence of major ports and urban centres (Sn, Bi, Ag). It seems therefore necessary to expand the short list of the seven metals commonly monitored to other TEs, what is today easily achievable as current analytical methods allow the simultaneous determination of all a series of TEs within the same sample. Furthermore, only a multielement analysis in appropriate bioindicator species allow to correctly intercompare the pollution status of numerous sampling sites. To do this, we have calculated proper environmental indices, the trace element pollution index TEPI and the trace element spatial variation index TESVI. The TEPI is an index of the global contamination of a site, giving the same weight to each TE after mean normalization of their environmental concentrations. The TESVI estimates the global spatial variability of environmental concentrations of each TE levels, taking into account both punctual contaminations in impacted sites and the overall coastal spatial heterogeneity between all monitored sites.These two indices were successfully applied both at large (French Mediterranean littoral) and small (a Bay) spatial scales. Furthermore, they can be used in the framework of an intercomparative study compiling data from any previous monitoring surveys. We also highlighted that the ecophysiology and surrounding levels of TEs influenced in an equivalent manner the bioaccumulation process of TEs in P. oceanica. Consequently, this natural cyclic evolution of TE concentrations should be systematically quantified in regional reference sites. Finally, the rapid and proportionnal accumulation of TEs in P. oceanica traps huge amounts of contaminants and can stock them for longer periods of time in their bellow grounds tissues. P. oceanica meadows therefore play an efficient role of natural filter of TE coastal pollutions. [less ▲]

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See detailA propos du retard de croissance intra-utérin
Saliba, Mariane ULg; Bourcy, Emilie ULg; Lapotre, Thibaut ULg et al

Poster (2014, March)

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See detailOn the use of O2/Ar and O2/N2 to estimate the biological carbon uptake in landfast sea ice
Zhou, Jiayun ULg; Delille, Bruno ULg; Brabant, F. et al

Poster (2014, March)

Sea ice is one of the largest biomes on Earth. The net community production (NCP) of the microorganisms living in sea ice impacts the dynamics of pCO2 in sea ice, and therefore the CO2 exchanges at the ... [more ▼]

Sea ice is one of the largest biomes on Earth. The net community production (NCP) of the microorganisms living in sea ice impacts the dynamics of pCO2 in sea ice, and therefore the CO2 exchanges at the air-ice-sea interfaces. As oxygen O2 and carbon C are both involved in the photosynthetic and respiration processes, one can theoretically assess NCP (in terms of C uptake) from O2 measurements. However, the concentration of O2 in sea ice depends not only on biological processes (i.e., NCP) but also on physical processes. We present a technique for assessing NCP in sea ice, based on the use of the O2/Ar ratio, which should correct for the physical contribution in O2 variations. We also compare the use of O2/Ar and O2/N2 for deriving NCP, and demonstrate that O2/Ar is more suitable, as it is more sensitive and less affected by gas diffusion and gas bubble formation during sea ice growth and decay than O2/N2. Using O2/Ar, we then provide conservative estimates of NCP in landfast sea ice, from ice cores collected in Barrow, from January through June 2009. The minimum estimate of the NCP in the whole ice cover reached 229 mg C.m-².d-1 in late spring. This is about 20 times higher than the atmospheric C uptake at that time identified from CO2 fluxes measurements at the ice-air interface, and therefore indicates that the main source of C used in the NCP was from the under-ice water. [less ▲]

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See detailControlled DCD donation is part of the solution to liver graft shortage, regardless of donor age
DETRY, Olivier ULg; MEURISSE, Nicolas ULg; DELWAIDE, Jean ULg et al

in Acta Gastro-Enterologica Belgica (2014, March), 77(1), 16

Aim: Results of donation after circulatory death (DCD) liver transplantation (LT) are impaired by ischemic bile duct lesions caused by procurement warm ischemia. Donor age is a risk factor in deceased ... [more ▼]

Aim: Results of donation after circulatory death (DCD) liver transplantation (LT) are impaired by ischemic bile duct lesions caused by procurement warm ischemia. Donor age is a risk factor in deceased donor LT, and particularly in DCD-LT. At the authors institute, age is not an absolute exclusion criterion to discard DCD liver grafts, controlled DCD donors receive comfort therapy before withdrawal, and cold ischemia is minimized. The aim of the present study was to report on the results of the first 10 years of this experience, and particularly on graft survival and the rate of post-transplant biliary complications, according to DCD donor age. 
 Methods: The authors retrospectively studied a consecutive series of 70 DCD-LT performed from 2003 to 2012, with at least one year of follow-up. This series was divided according to donor’s age, including 32 liver grafts from donors <55years, 20 between 56 and 69 years, and 18 from older donors >69 years. The three groups were compared in terms of donor and recipient demographics, procurement and transplantation conditions, peak laboratory values during the first post-transplant 72 hours, and results at one and four years. Median follow-up was 43 months. 
 Results: Overall graft survival was 98.5%, 91.4% and 69.5% at 1 month, 1 year and 4 years, respectively, without graft loss secondary to ischemic bile duct lesions. Cancer was the primary cause of graft loss and patient death. No difference other than age was noted between the three groups in donor and recipient characteristics, and in procurement conditions. There was no primary non-function but one patient needed re-transplantation for artery thrombosis. Biliary complications occurred similarly in the three groups. Graft and patient survival rates were not different at one and four years between the three groups. During the study period, there was an increasing liver procurement and transplantation activity, and in 2012, 30% of performed LT were DCD-LT, allowing a mean LT waiting time of 66 days. 
 Conclusions: This study shows comparable results between controlled DCD-LT from younger and older donors. Donor age >50 years should not be a contraindication to DCD-LT if other donor risk factors (such as warm and cold ischemia time) are minimized. DCD-LT with short cold ischemia may provide a significant source of liver grafts, decreasing waiting time. [less ▲]

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See detailSnow cover and short-term synoptic events drive biogeochemical dynamics in winter Weddell Sea pack ice (AWECS cruise - June to August 2013)
Tison, J.-L.; Delille, Bruno ULg; Dieckmann, G. et al

Conference (2014, March)

This paper presents the preliminary results of an integrated multidisciplinary study of pack ice biogeochemistry in the Weddell Sea during the winter 2013 (June-August). The sea ice biogeochemistry group ... [more ▼]

This paper presents the preliminary results of an integrated multidisciplinary study of pack ice biogeochemistry in the Weddell Sea during the winter 2013 (June-August). The sea ice biogeochemistry group was one of the components of the AWECS (Antarctic Winter Ecosystem and Climate Study) cruise (Polarstern ANTXXIX-6). A total of 12 stations were carried out by the sea ice biogeochemistry group, which collected a suite of variables in the fields of physics, inorganic chemistry, gas content and composition, microbiology, biogeochemistry, trace metals and the carbonate system in order to give the best possible description of the sea ice cover and its interactions at interfaces. Samples were collected in the atmosphere above (gas fluxes), in the snow cover, in the bulk ice (ice cores), in the brines (sackholes) and in the sea water below (0m, 1m, 30 m). Here we present the results of basic physico-chemical (T°, bulk ice salinity, brine volumes, brine salinity, Rayleigh numbers) and biological (Chla) measurements in order to give an overview of the general status of the Weddell Sea winter pack ice encountered, and discuss how it controls climate relevant biogeochemical processes. Our results from the first set of 9 stations, mainly sampled along the Greenwich meridian and the easternmost part of the Weddell Sea definitively refute the view of a biogeochemically “frozen” sea ice during the Winter. This has already been demonstrated for the Spring and Summer, but we now see that sea ice sustains considerable biological stocks and activities throughout the Winter, despite the reduced amount of available PAR radiation. Accretion of the snow cover appears to play an essential role in driving biogeochemical activity, through warming from insulation, thus favouring brine transport, be it through potential convection, surface brine migration (brine tubes) or flooding. This results in a “widening” of the internal autumn layer (quite frequent in this rafting-dominated sea ice cover) and increase of the chla burden with age. Results from the second set of 3 stations in the western branch of the Weddell Sea gyre confirm that it comprises a mixture of older fast/second year ice floes with younger first-year ice floes. The older ice had the highest Chla concentrations of the entire cruise (>200 mgl-1), in an internal community enclosed within desalinized impermeable upper and lower layers. The first-year ice differs from that in the eastern Weddell Sea as it is dominated by columnar ice and (weak) algal communities are only found on the bottom or near the surface (no internal maximum). [less ▲]

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See detailDe rol van de bibliotheek in tijden van information overload
Decoster, Sara ULg

in Cahiers de la Documentation = Bladen voor Documentatie (2014, March), 68(1),

Cet article étudie le rôle que peut jouer la bibliothèque en temps d’information overload et part des deux composantes de base du phénomène de l’infobésité : en premier lieu, un flot de données ... [more ▼]

Cet article étudie le rôle que peut jouer la bibliothèque en temps d’information overload et part des deux composantes de base du phénomène de l’infobésité : en premier lieu, un flot de données objectivement important, et, en second lieu, la manière dont ces données sont traitées par le sujet humain, l’usager. Pour gérer l’afflux de données constant, la bibliothèque offre d’abord un outillage technique. Le développement récent des outils « discovery » peut être resitué dans cette veine. Deuxièmement, c’est en investissant dans les compétences informationnelles des utilisateurs que la bibliothèque peut lutter contre le versant subjectif de l’infobésité. Dans ce processus, la communication joue un rôle primordial. [less ▲]

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See detailUsing stable isotopes to unravel the role of sea-ice in the methane cycle
Sapart, C.J.; Zhou, Jiayun ULg; Niemann, T et al

Poster (2014, March)

Methane (CH4) plays an important role in the Earth’s climate system. The atmospheric CH4 concentration has increased in concert with the industrialization, but since the mid 80’s the CH4 growth rate ... [more ▼]

Methane (CH4) plays an important role in the Earth’s climate system. The atmospheric CH4 concentration has increased in concert with the industrialization, but since the mid 80’s the CH4 growth rate decreased to reach a near-zero level in 2000 and started to increase again from 2007 on. However, the underlying variations in sources and/or sinks that cause these variations are to date not well understood. To predict future climate, it is essential to unravel the processes controlling the CH4 cycle, especially in the Arctic regions, which are highly vulnerable to climate change and contain large CH4 reservoirs. Recently, an unexpected CH4 excess has been reported above Arctic sea-ice showing that sea-ice might play a significant role in the CH4 cycle. Nonetheless, the nature of the process leading to CH4 production in or nearby sea-ice has not yet been identified. We applied a new multi-proxy approach merging atmospheric chemistry, glaciology and biogeochemistry to understand and quantify the processes responsible for the CH4 excess above sea-ice. We performed CH4 isotope (13C and D) analyses on sea-ice samples, as well as microbial (lipid biomarkers) and geochemical measurements, to determine the possible pathways involved in CH4 production and removal in or nearby sea-ice. We will present results from sea-ice samples drilled above the shallow-shelf in Barrow (Alaska) from January to June 2009 as well as above deep Southern Ocean locations in 2013. Those results allow investigating the seasonality and spatial variability in methane formation and removal pathways associated to the methane enclosed in sea-ice. [less ▲]

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See detailCertificat d’université en tutorat à distance : une approche de formation isomorphique pour acquérir des compétences de e-tuteur
Denis, Brigitte ULg

in Tutorales (2014, March), 12

Depuis plus d'une dizaine d'années, de nombreux auteurs ont décrit les rôles des tuteurs dans les dispositifs de formation en ligne (Depover et al, 2011 ; Salmon, 2000). La "présence" et les interventions ... [more ▼]

Depuis plus d'une dizaine d'années, de nombreux auteurs ont décrit les rôles des tuteurs dans les dispositifs de formation en ligne (Depover et al, 2011 ; Salmon, 2000). La "présence" et les interventions de ces derniers s'avèrent un facteur important dans l'efficacité de tels dispositifs, qu'il s'agisse de maintien de la motivation des apprenants ou du processus d'apprentissage. La variété des méthodologies mises en œuvre dans les scénarios de formation (apprentissage collaboratif, coopératif, individuel...) entraînent des modalités d'interaction différentes entre e-tuteur et apprenants. Se basant sur les étapes de formation au e-tutorat décrites par Denis (2003), un processus original de formation de e-tuteurs est proposé afin de rencontrer la diversité et l'adéquation des profils à adopter selon le contexte considéré. Le scénario de formation au e-tutorat recourt au principe d'isomorphisme en pédagogie (Leclercq, 1998). Outre des apports théoriques relatifs à la problématique traitée et une approche réflexive sur cette dernière, les formés sont amenés à vivre différentes situations d'animation qui pourront (ou non) les inspirer dans leurs futures pratiques de tutorat à distance. Par ailleurs, la formation met l'accent sur le respect d'une triple concordance entre les compétences visées, les activités mises en place et les modalités d'évaluation. [less ▲]

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See detailInvestigating iron and organic matter incorporation in growing sea ice
Janssens, J.; Delille, Bruno ULg; de Jong et al

Conference (2014, March)

High concentration of exopolysacharides (EPS) and iron have been found in sea ice surrounding the Antarctic continent. However, the mechanisms leading to that enrichment remain unclear. Scavenging of iron ... [more ▼]

High concentration of exopolysacharides (EPS) and iron have been found in sea ice surrounding the Antarctic continent. However, the mechanisms leading to that enrichment remain unclear. Scavenging of iron by organic matter in seawater and entrainment during sea ice formation are thought to be responsible for the accumulation of iron in sea ice. EPS could also play a role in the iron passive chelative scavenging process in sea ice and in the increase of iron bioavailability. Our study investigates the processes responsible for the accumulation of iron (dissolved, particulate and total dissolvable iron), EPS, dissolved and particulate organic matter, macro-nutrients (silicic acid, nitrate and nitrite, phosphoric acid and ammonium), chlorophyll a and sea ice algae in young sea ice during an Australian-lead spring voyage off East Antarctica (SIPEX II September – November 2012) and a German-lead winter voyage to the Weddell Sea (AWECS June – August 2013). We used a combination of field- (“in situ”) and laboratory- based sea ice growth time-series experiments. In addition different types of newly formed sea ice as pancake ice, grey ice, frost flowers and slush were collected during both voyages as a means to compare and validate the experimental data. To our knowledge, this is the first report on the biogeochemical properties of newly formed Antarctic pack ice samples in the winter. Ice temperature, salinity and textures are also presented to support the biogeochemical observations at the onset of sea ice formation. [less ▲]

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See detailAssessment using e-Health technologies in pediatric psychology: Developing an App on iPad for the Quality of Life Systemic Inventory for Children (QLSI-C)
Toucheque, Malorie ULg; Tilkin, Caroline; Dupuis, Gilles et al

Poster (2014, March)

Objective:Integration of e-Health technologies for purposes of both assessment and intervention has recently become an interest area in pediatric psychology. The purpose of this study is to present ... [more ▼]

Objective:Integration of e-Health technologies for purposes of both assessment and intervention has recently become an interest area in pediatric psychology. The purpose of this study is to present psychometric characteristics of a technology-based (i.e., iPad administration) approach for measuring quality of life (QoL) in children. Methods: Sample consisted of 80 children (8-12 years) recruited from elementary schools in Belgium. They completed the Quality of Life Systemic Inventory for Children (QLSI-C) twice over a two-week delay, in a crossover design that used paper and iPad-based modes of administration. QLSI-C takes a unique approach to assessing QoL relative to existing measures. Specifically, it considers QoL to be the difference (gap score) between the present situation (state score) and the child’s expectations (goal), weighted by the importance (rank) assigned for each life domain. Cronbach’s coefficient was computed to assess internal consistency for each of the four global scores (State, Goal, Gap, Rank). ANOVA was used to assess the equivalence of the new iPad and paper formats. Test-retest reliability was assessed using correlational analysis. Results: Alpha coefficients for the global scores were as follows: State (.87), Goal (.94), Gap (.72), and Rank (.79). ANOVA results indicate that main effects for group (p = 0.75) and time (p= 0.31) were not statistically significant, nor was the interaction effect (p = 0.86) for the QoL score (Gap). Correlations for the test-retest reliability of the 4 global scores ranged from .66 to .90. Conclusions: The iPad format of QLSI-C appears valid in comparison to the original paper format and test-retest stability for the iPad format is good. This technology approach to assessment is more attractive for children, decreases time for administration, and enhances the ease of scoring. Thus, these advantages might encourage both clinicians and researchers to consider using e-Health developments in assessment in pediatric psychology. [less ▲]

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See detailTGF-B induced protein IG-H3 is essential for the growth of human liver metastases
Castronovo, Vincenzo ULg; Blomme, Arnaud; Delvenne, Philippe ULg et al

in Acta Gastro-Enterologica Belgica (2014, March), 77(1), 05

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See detailAdherence to Continuous Positive Airway Pressure (CPAP) Therapy
Deflandre, Eric; Degey, Stéphanie; BONHOMME, Vincent ULg et al

in CHEST Journal (2014, March), 145

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See detailContributions to transnational flood risk management in the Meuse basin
Dewals, Benjamin ULg; Erpicum, Sébastien ULg; Archambeau, Pierre ULg et al

in European Symposium on Flood Frequency Estimation and Implications for Risk Management (2014, March)

Experience in transboundary river basins emphasizes the need for more cooperative transnational water management. In this respect, the Interreg IVB project AMICE aims at developing a shared adaptation ... [more ▼]

Experience in transboundary river basins emphasizes the need for more cooperative transnational water management. In this respect, the Interreg IVB project AMICE aims at developing a shared adaptation strategy of the basin of the river Meuse to the hydrological impacts of climate change. The basin covers parts of France, Belgium, Germany and the Netherlands. The project combines scientific research with innovative natural and structural water retention measures, as well as enhanced transnational crisis management. In this framework, common climate and hydrological scenarios were derived for the time horizons 2021-2050 and 2071-2100. A “coordinated” procedure was set up to conduct the first hydraulic modelling of the entire river Meuse, from its spring to its mouth. For the considered climate scenarios, the increases in future flood levels were found about twice higher in the central part of the Meuse basin compared to the upper and lower parts. This distinctive spatial pattern results from the morphology of the valley. The characteristics of the hydraulic models used for this “coordinated” analysis differed significantly from one region to the other (e.g., 1D vs. 2D, steady vs. unsteady). Therefore, a more refined analysis was undertaken on a 100 km long stretch of the Meuse, crossing the border between Belgium and the Netherlands, using very similar (“harmonized”) models for the whole computation (2D unsteady models). As a result, the influence of using different interconnected models could be appreciated. The results of hydraulic modelling were used to conduct damage assessment based on a common methodology throughout the Meuse basin and combined with landuse change scenarios in the floodplains (change in vulnerability of the floodplains). In turn, several adaptation measures were tested, including upstream water retention, dredging as well as upgrade of flood defences and mobile weirs. Hydrological and hydraulic modelling was also performed for a sub-basin of the river Meuse, partly controlled by two large reservoirs. A detailed model of the operation rules of these reservoirs was implemented. This enabled to investigate the impact of the considered climate change scenarios on the performance of these multi-purpose reservoirs as well as to investigate possible enhancements in the operation rules, which may serve as adaptation measures to compensate for the detrimental effects of climate change. [less ▲]

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See detailBiological and physical controls on DMS,P dynamics in ice-shelf-influenced fast ice
Carnat, G.; Zhou, Jiayun ULg; Papakyriakou, T. et al

Conference (2014, March)

Dimethylsulfide (DMS) is a volatile sulphur compound produced by the degradation of dimethylsulphoniopropionate (DMSP), a metabolite synthesized by microalgae as i.a. cryoprotectant and osmoregulator. It ... [more ▼]

Dimethylsulfide (DMS) is a volatile sulphur compound produced by the degradation of dimethylsulphoniopropionate (DMSP), a metabolite synthesized by microalgae as i.a. cryoprotectant and osmoregulator. It is also an important climate-active gas, being the primary source of marine-derived sulphate aerosols which play an important role in the earth-atmosphere radiation balance. In the last two decades, there has been an increasing interest in the role of the marine cryosphere in the DMS,P cycle, motivated by repeated observations of very high DMS,P concentrations in sea ice. However, our understanding of the factors driving the spatiotemporal variations of these high concentrations, and hence the fate of the sea ice DMS pool, remains limited. To date, studies have essentially focused on biotic factors, attributing the high DMS,P concentrations to the high biomass of the sympagic communities, and to their strong physiological response to the low temperature and high salinity stresses of the brine habitat. We present here an approach integrating both biotic and abiotic factors, as we investigate the influence of sea ice growth processes and brine dynamics on the DMS,P cycle. We focus on a fast ice site (Cape Evans, McMurdo Sound, Antarctica) under the influence of ice-shelf waters, and provide measurements covering a full cycle of ice growth. We show a good correspondence between isolated maxima of DMS,P in interior ice and the occurrence of platelet crystals in the ice texture. We develop the idea that platelet ice formation in May strongly modifies the production of DMS,P by (1) favoring the incorporation of strong DMSP producers and by (2) exposing these producers to stronger environmental stresses. We then show the influence of the development and decline of a strong diatom bloom from October to November on bottom ice DMS,P concentrations. Finally, we show that the increase in brine volume fraction (permeability) on warming in early December triggers (1) an important release of DMS to the ocean through brine convection, and (2) a vertical redistribution of DMSP across the ice. [less ▲]

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See detailDo large companies ignore formal sustainability management controls? An exploration amongst corporate practices
Crutzen, Nathalie ULg; Schaltegger, Stefan

in EMAN (Ed.) Proceedings of the 2014 EMAN conference (2014, March)

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See detailMatrimonial property and Succession under EU Private International Law : a Happy Marriage?
Wautelet, Patrick ULg

Conference (2014, March)

In this presentation, I attempt to examine the relationship between the Succession Regulation (650/2012) and matrimonial property. I do so by looking at the difficulties which could arise both from a ... [more ▼]

In this presentation, I attempt to examine the relationship between the Succession Regulation (650/2012) and matrimonial property. I do so by looking at the difficulties which could arise both from a practical perspective as well as from a more fundamental angle. Attention is given to the future Matrimonial Property Regulation and the need to coordinate it with the Succession Regulation. [less ▲]

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See detailLe schizophrène : du paradoxe évolutionniste à la psychopathologie éthologique
Englebert, Jérôme ULg

Conference (2014, February 28)

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See detailSCC-Optimiser la pertinence du parcours patient
WANG, François-Charles ULg

Conference (2014, February 28)

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See detailLa Vierge protectrice des villes
Delfosse, Annick ULg

Conference (2014, February 28)

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See detailRevisiting Snu spaces with wavelet leaders to detect non concave and non increasing spectra
Esser, Céline ULg

Poster (2014, February 27)

A multifractal formalism is a formula which is expected to yield the spectrum of singularities of a function from quantities which are numerically computable. The most widespread of these formulas is the ... [more ▼]

A multifractal formalism is a formula which is expected to yield the spectrum of singularities of a function from quantities which are numerically computable. The most widespread of these formulas is the so-called thermodynamic mul- tifractal formalism, based on the Frish-Parisi conjecture. It presents two drawbacks: it can hold only for spectra which are concave and it can only yield the increasing part of the spectrum. This first problem can be avoided using Sν spaces. The second one can be taken care using the wavelet leaders method. In this poster, we present a new multifractal formalism based on a generaliza- tion of the Sν spaces using wavelet leaders. It allows to detect non concave and non increasing spectra. We compare this formalism with the Sν method and the wavelet leaders method. It is based on joint works with F. Bastin, S. Jaffard, T. Kleyntssens and S. Nicolay. [less ▲]

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See detailLa jurisprudence européenne de 2013 en matière de fiscalité directe et ses conséquences en Belgique. Morceaux choisix
Richelle, Isabelle ULg; Traversa, Edoardo

Conference (2014, February 27)

Actualité relative aux conventions préventives de la double imposition et à la jurisprudence de la Cour de justice; le point sur les récentes initiatives de l’OCDE et de la Commission européenne en ... [more ▼]

Actualité relative aux conventions préventives de la double imposition et à la jurisprudence de la Cour de justice; le point sur les récentes initiatives de l’OCDE et de la Commission européenne en matière de lutte contre la planification fiscale agressive et contre l’érosion de l’assiette fiscale. [less ▲]

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See detailThe end of roaming in the forest causes a loss of timber resources: the paradox of slash-and-burn agriculture
Morin-Rivat, Julie ULg; Fayolle, Adeline ULg; Favier, Charly et al

Conference (2014, February 27)

Tropical forests are not believed as pristine anymore. Their structure and specific composition are induced by past climatic and human disturbances over years. In the African moist forests, the emergent ... [more ▼]

Tropical forests are not believed as pristine anymore. Their structure and specific composition are induced by past climatic and human disturbances over years. In the African moist forests, the emergent trees are mainly light-demanding. These trees are considered to derive from the recent disturbances of the last centuries. Most of them are exploited for their timber. However, several of these tree species are currently suffering from a lack of regeneration that threatens the specific diversity of the forests and the sustainability of timber exploitation. Through dendrometric and radiocarbon analyses we found that the majority of the trees of the Congo Basin are not older than 160 years. This corresponds to about the year 1850 when the Europeans colonized the inner regions of Central Africa. By reassembling people along the road axes, the colonial administration reduced the forest roaming. Former activities such as slash and burn agriculture created large openings in the canopy that allowed light-demanding tree species to establish. Currently we observed that timber logging does not provide openings large enough for the recruitment of these species. We thus anticipate that adjustments in forest management strategies shall be made to preserve the forest resources, for instance by recreating the conditions of slash and burn agriculture. [less ▲]

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See detailPlants & metals in soil : the concept of phytoremediation
Evlard, Aricia ULg; Colinet, Gilles ULg; Druart, Philippe

Conference (2014, February 26)

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See detail6. Lutte intégrée contre les maladies
Duvivier, Maxime; Bataille, Charlotte; Mahieu, Olivier et al

in Bodson, Bernard; Destain, Jean-Pierre (Eds.) Livre blanc céréales (2014, February 26)

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See detailOn the use of Belgian Soil Map to predict risk of nitrate and pesticide lixiviation
Bah, Boubacar Billo ULg; Vandenberghe, Christophe ULg; Deneufbourg, Mathieu ULg et al

Poster (2014, February 26)

Pollution by nitrate and pesticides has impacts on drinking water reserves and aquatic systems. Nowadays, this problem is the key point of the European Policy with the implementation of the Water ... [more ▼]

Pollution by nitrate and pesticides has impacts on drinking water reserves and aquatic systems. Nowadays, this problem is the key point of the European Policy with the implementation of the Water Framework Directive (Directive 2000/60/EC). According to these legislations, Member States are supposed to take measures to limit environmental and toxicological effects caused by nitrate and pesticides use. This paper presents three different approaches allowing assessment of diffuse (non-point sources) pollution risks of water resources by nitrate and pesticides. The first approach consists on the interpretation of the geomorphopedological information (geologic substratum type, presence of karst phenomena, soil texture, natural drainage, profile development, type and percent of stoniness, soil thickness, …) provided by the Digital Soil Map of Wallonia. Soil physical characteristics are assessed in terms of soil water percolation/infiltration, runoff, pollutants retention, mineralization, and erosion. Second approach consists on the use of spatially distributed mechanistic models. Nitrate lixiviation from agricultural land to groundwater has been simulated from the SWAT model. Pesticide lixiviation from soil to groundwater has been predicted from the one-dimensional, dynamic, multi-layered model named PEARL (Pesticide Emission Assessment at Regional and Local scales). Model input parameters are mainly extracted from the existing soil physical and physico-chemical, crop and pesticides properties databases. Relevant soil parameters not directly available in existing databases, such as bulk density, hydraulic conductivity, potential evapotranspiration… have been derived from pedotransfers functions. Third approach consists on in situ lixiviation studies by the way of lysimeters. Concentrations measured at the bottom (2 m deep) of lysimeters represent a straight “index of risk” for groundwater and, on the other hand, allow the validation of simulation models used to predict nitrate and pesticides lixiviation risk under different scenarios. The Digital Soil Map of Wallonia, one of the core data source, allows the spatialisation of the predicted lixiviation risk at regional level, providing to the local authorities and the decision makers a tool for the identification of the areas at risk of pollution, where specific monitoring actions and prevention measures for the protection of waters can be implemented. [less ▲]

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