References of "Scientific congresses and symposiums"
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See detailThe seamod.ro operational stochasting Black Sea forecasting system
Vandenbulcke, Luc ULg; Capet, Arthur; Grégoire, Marilaure ULg et al

Poster (2015, May 08)

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See detailLa médiation, un lien social à reconstruire.
Bachelet, Jean-François ULg

Conference (2015, May 08)

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See detailFast Userspace Packet Processing
Barbette, Tom ULg; Soldani, Cyril ULg; Mathy, Laurent ULg

in Proceedings of ANCS 2015 (2015, May 07)

In recent years, we have witnessed the emergence of high speed packet I/O frameworks, bringing unprecedented network performance to userspace. Using the Click modular router, we first review and ... [more ▼]

In recent years, we have witnessed the emergence of high speed packet I/O frameworks, bringing unprecedented network performance to userspace. Using the Click modular router, we first review and quantitatively compare several such packet I/O frameworks, showing their superiority to kernel-based forwarding. We then reconsider the issue of software packet processing, in the context of modern commodity hardware with hardware multi-queues, multi-core processors and non-uniform memory access. Through a combination of existing techniques and improvements of our own, we derive modern general principles for the design of software packet processors. Our implementation of a fast packet processor framework, integrating a faster Click with both Netmap and DPDK, exhibits up-to about 2.3x speed-up compared to other software implementations, when used as an IP router. [less ▲]

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See detailSelf-defining memories and self-concept clarity: A comparative study of depressed patients, bipolar patients and healthy subjects
Wagener, Aurélie ULg; Boulanger, Marie ULg; Blairy, Sylvie ULg

Poster (2015, May 06)

Depressed and bipolar patients suffer from autobiographical memory (AM) deficits. For instance, depressed patients present an overgeneralisation and a mood congruence biases. Indeed, these patients seem ... [more ▼]

Depressed and bipolar patients suffer from autobiographical memory (AM) deficits. For instance, depressed patients present an overgeneralisation and a mood congruence biases. Indeed, these patients seem to have difficulties to recall specific and positive memories. The present study focusses on a particular kind of memories: the self-defining memories (SDMs). SDMs are highly pertinent for self-building: they help to define in the most clearly way our perception of ourselves. Because SDMs have not been studied a lot since yet in these two disorders, our goal is to assess the impact of general AM biases on SDMs. Then, the present study pursues two main aims: 1) To assess SDM’s characteristics, 2) To assess the relationship between SDM and self-concept clarity. To reach our objective, depressed and bipolar patients are compared to healthy subjects. Participants are asked to complete SDMs exercises that are recalling six important events which happened in their life. These SDMs are assessed on four variables: specificity, impact, meaning making, contain. Self-concept clarity and mood are also assessed. Until now, 17 depressed patients, 16 bipolar patients and 18 healthy controls participate in this study. Preliminary results do not highlight difference between our groups on specificity. Marginal effects appear for meaning making with healthy subjects recalling more meaning making events. Results show that depressed patients present a mood congruence. The final results will be presented during the convention, as data-collection is on-going and will end in April. Experimental and clinical implications of our results will be discussed. [less ▲]

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See detailProteome variations in Macrobrachium rosenbergii exposed to chlordecone: a gel-free proteomic approach
Lafontaine, Anne ULg; De Pauw, Edwin ULg; Forget-Leray, Joelle et al

Poster (2015, May 06)

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See detailTowards an extension of the catalogue of particle-accelerating colliding-wind binaries
De Becker, Michaël ULg

Conference (2015, May 05)

Particle-accelerating colliding-wind binaries (PACWBs) constitute a class of massive stars known to be able to accelerate charged particles up to relativistic velocities. The latter property is identified ... [more ▼]

Particle-accelerating colliding-wind binaries (PACWBs) constitute a class of massive stars known to be able to accelerate charged particles up to relativistic velocities. The latter property is identified mainly through the detection of synchrotron radiation in the radio domain, and in a few cases thanks to the detection of non-thermal radiation in the high energy domain. The catalogue of PACWBs contains about 40 objects, covering a wide parameter space in terms of stellar wind and orbital parameters. So far, there is no evidence for a strict criterion to justify the occurrence of a particle acceleration process only in a small fraction of the colliding-wind binaries population, admitting the possibility that it might be a frequent property among massive stars. In this contribution, I address the issue of the frequency of particle accelerators among massive binaries, and I discuss observation strategies aiming at identifying new members of the catalogue. [less ▲]

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See detailLes tabous à l’école : quelle place pour le juge en classe ?
Grandjean, Geoffrey ULg

Conference (2015, May 05)

L’objectif de la conférence est de revenir sur le concept de tabou en le liant à différents cas concrets rencontrés en milieu scolaire. L’exposé montre la place croissante accordée aux juges face à des ... [more ▼]

L’objectif de la conférence est de revenir sur le concept de tabou en le liant à différents cas concrets rencontrés en milieu scolaire. L’exposé montre la place croissante accordée aux juges face à des tabous qui suscitent des conflits. Une réflexion politologique est proposée par rapport au phénomène de judiciarisation. [less ▲]

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See detailIconic turn et critique du paradigme langagier
Hagelstein, Maud ULg

Conference (2015, May 05)

Je voudrais envisager ici le problème de la légalité des significations dans le champ non-verbal du visuel, tel qu’il est envisagé par un théoricien de l’image allemand actuel (G. Boehm). On pourrait en ... [more ▼]

Je voudrais envisager ici le problème de la légalité des significations dans le champ non-verbal du visuel, tel qu’il est envisagé par un théoricien de l’image allemand actuel (G. Boehm). On pourrait en effet dégager – selon la proposition de Boehm – un principe formel (au moins) qui structure l’émergence de significations dans le domaine du visuel. Boehm ne parle de grammaire à proprement parler que pour s’en écarter (il rejette l’usage de la grammaire prédicative pour la compréhension des images). [less ▲]

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See detailPsychological processes leading to activation or avoidance: Protective and vulnerability factors to depression
Wagener, Aurélie ULg

Conference (2015, May 05)

Kinderman (2005, 2013) elaborated a psychological model of mental ill-health according to which biological, social and circumstantial factors lead to mental disorders through their conjoint effects on ... [more ▼]

Kinderman (2005, 2013) elaborated a psychological model of mental ill-health according to which biological, social and circumstantial factors lead to mental disorders through their conjoint effects on psychological processes (PP). Our research adopted the same framework. It focused on PP which characterize depression. More precisely, since inactivity (also conceptualized as behavioural avoidance) is one of the main feature of depression, the present research focused on PP which influence the behavioural avoidance (vulnerability factor to depression) and the behavioural activation (protective factor for depression). Three main aims were pursued: To investigate the influence of the biased PP on the behavioural avoidance. To find the PP which have a positive influence on the behavioural activation. To present an integration of our results with Kinderman’s model. Four hundred seventy-seven community adults (358 women, 119 men; x ̅ age = 34.25, SD = 11.85) completed an online survey assessing PP (negative repetitive thoughts, emotion regulation strategies, environmental rewards, self-image, inhibition/approach), avoidance, activation and depression. Since several questionnaires were used to assess each PP, factorial scores were computed for each one. Overall, confirmatory factor analyses highlighted that avoidance is positively linked to ruminations, negative emotion regulation strategies and poor environmental rewards and that activation is positively linked to positive self-image and high environmental satisfaction. Results will also be discussed according to the sex. According to their influence on both avoidance and activation, the environmental reward and the emotion regulation strategies appear to be important variables to work on during the treatment of depression. [less ▲]

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See detailUse of GEOS-Chem for the interpretation of long-term FTIR measurements at the Jungfraujoch and other NDACC sites
Mahieu, Emmanuel ULg; Bovy, Benoît ULg; Bader, Whitney ULg et al

Poster (2015, May 04)

We present recent and ongoing investigations using 3D CTM GEOS-Chem model simulations for the interpretation of long-term FTIR measurements performed at selected NDACC sites.

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See detailThe crucial role of soil when modelling the impact of climate change on crop production
Basso, Bruno; Dumont, Benjamin ULg; Shcherbak, Iurii et al

in Shirmohammadi, Adel; Bosch, David; Muñoz-Carpena, Rafa (Eds.) Proceedings of the 1st ASABE Climate Change Symposium - Adaptation and Mitigation (2015, May 03)

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See detailCarbon dioxide, a cheap bio-sourced building block for cyclic carbonates and non-isocyanate polyurethanes
Gennen, Sandro ULg; Alves, Margot ULg; Tassaing, Thierry et al

Poster (2015, May 03)

Due to concerns about global warming combined with the decrease of fossil resources, new carbon feedstocks that are abundant, renewable, non-toxic, inexpensive and environmentally friendly must be ... [more ▼]

Due to concerns about global warming combined with the decrease of fossil resources, new carbon feedstocks that are abundant, renewable, non-toxic, inexpensive and environmentally friendly must be explored to produce chemicals. Besides the valorization of bio-based raw materials, the chemical transformation of carbon dioxide into added-value products has gained interest in both academia and industry. To date, the chemical fixation of CO2 onto epoxides with the formation of cyclic carbonates is one of the most promising ways to valorize CO2 at an industrial scale. Indeed, cyclic carbonates find applications as electrolytes in lithium ion batteries, as aprotic polar solvents or as useful intermediates for polycarbonates. Cyclic carbonates also react with primary amines to produce 2-hydroxyethylurethane. This reaction can be extrapolated to the synthesis of non-isocyanate polyurethanes (NIPU) by polyaddition of bifunctional cyclic carbonates with diamines.5 This study aims (i) at developing a new highly efficient organocatalyst for the synthesis of cyclic carbonates under mild experimental conditions and (ii) their valorization as monomers to produce non-isocyanate polyurethanes. First, we have identified a bicomponent organocatalyst, composed of a judicious combination of an organocatalyst and an activator, for the very fast synthesis of cyclic carbonates from CO2 and epoxides under very mild reaction conditions. Kinetics of reactions were followed by online Raman spectroscopy measurements under pressure. NMR titrations were realized to evidence the mechanism of activation of this novel organocatalytic system that will be discussed in detail in this talk. The second objective relies on the development of new efficient organocatalysts for the synthesis of high molar masses NIPUs in short reaction times. Organic compounds interacting with the cyclic carbonate by hydrogen bonding were identified and their catalytic activity was demonstrated for model compounds. [less ▲]

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See detailBiscuits et thé à la menthe aux fêtes interculturelles. Entre essentialisation et participation des femmes marocaines en Italie.
Mescoli, Elsa ULg

Conference (2015, May)

Cette communication est issue d’une recherche ethnographique autour des pratiques culinaires d’un groupe de femmes marocaines résidentes dans une ville de la province de Milan, en Italie. Le matériel ... [more ▼]

Cette communication est issue d’une recherche ethnographique autour des pratiques culinaires d’un groupe de femmes marocaines résidentes dans une ville de la province de Milan, en Italie. Le matériel collecté au sein des entretiens et des observations a permis d’étudier d’un côté la définition des sujets au travers des pratiques alimentaires, d’un autre côté leur modalité de prendre part à la vie sociale locale. Grâce aux activités de la vie quotidienne, une appartenance culturelle et religieuse peut être affirmée, en permettant ainsi la revendication du « droit à la diversité ». La performance publique des pratiques culinaires permet aux femmes considérées d’exercer une agency à l’intérieur des espaces institutionnellement concédés à l’expression des migrants. Lors des fêtes interculturelles, les rituels d’une sorte de « cannibalisme exogène » se mettent en place : la population majoritaire, en goûtant les plats des Autres, incorpore la diversité afin de la contrôler. Néanmoins, les femmes migrantes en charge des préparations choisissent activement quels ingrédients (du soi et des plats) faire consommer, en présentant ainsi certains aspects qui vont au-delà de la culture alimentaire. Le partage de nourriture leur permet d’assumer un rôle actif dans la communauté locale, tout en affirmant leurs propres spécificités. Les femmes considérées acquièrent une position politiquement importante au sein de la société et sont ainsi légitimées à participer aux débats et décisions autour de certains questions clefs de la pratique de la diversité. [less ▲]

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See detailPatch types in Posidonia oceanica meadows around Corsica. How can we use them in seascape ecology?
Abadie, Arnaud ULg; Bonacorsi, Marina; Gobert, Sylvie ULg et al

Conference (2015, May)

The meadows formed by the Mediterranean seagrass Posidonia oceanica are subjected to various natural (e.g., water movement, light availability, sedimentation) and anthropogenic (e.g., anchoring, trawling ... [more ▼]

The meadows formed by the Mediterranean seagrass Posidonia oceanica are subjected to various natural (e.g., water movement, light availability, sedimentation) and anthropogenic (e.g., anchoring, trawling, fish farms, explosives) phenomena that erode them and create diverse types of patches. The assemblage of the P. oceanica matrix and these patches creates particular seascapes. On the basis of this assessment, we aimed to investigate the importance of the patch type in structuring P. oceanica seascapes and to offer new prospects in the large scale studies of seagrass meadows. Five sites encompassing large P. oceanica meadows ranging from 1.86 km² to 4.42 km² along the Corsican coast (France) were considered. Eleven patch types with different sizes, shapes and origins were identified using side scan sonar images (sonograms). Five were recognized as natural and five as anthropogenic. One can be of both origins. The resolution of the sonograms allowed to detect patches of various sizes ranging from 1 m² to 111 829 m². The relation between structural characteristics of patches and the whole seascape aspect was explored using seven landscape metrics relevant for the study of meadows patchiness (patch area, mean radius of gyration, area-weighted radius of gyration, coefficient of variation of the Euclidean nearest-neighbor distance, area-weighted perimeter-area ratio, landscape division index, number of patches). Only a small number of patch types appears to play the strongest role in the characterization of the P. oceanica seascapes. Furthermore, the use of seascape structures seems to be suitable for the development of new tools like indices for the assessment of human impacts on P. oceanica meadows. In this perspective we propose a new and simple index, the Patchiness Source Index (PaSI), to estimate the origin of the patchiness (natural or anthropogenic) for a given area. A landscape approach, as well as information on patch dynamic, should be integrated in the new indices that aim to assess the state of conservation of the whole P. oceanica ecosystem. [less ▲]

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See detailRocking behaviour of simple unreinforced load-bearing masonry walls including soundproofing rubber layers
Mordant, Christophe ULg; Denoël, Vincent ULg; Degée, Hervé

in Proceedings of 5th ECCOMAS Thematic Conference on Computational Methods in Structural Dynamics and Earthquake Engineering (2015, May)

This paper compares experimental measurements with predictions of different rocking models. These comparisons are carried out on the base of recent experimental results obtained by shake-table tests of ... [more ▼]

This paper compares experimental measurements with predictions of different rocking models. These comparisons are carried out on the base of recent experimental results obtained by shake-table tests of four simple unreinforced load-bearing clay masonry walls that have exhibited a significant rocking behaviour for the highest acceleration inputs. In a first stage, the simple model proposed by Housner is used after slight modifications needed to properly consider the actual mass distribution. Two parameters are identified as governing the model response, namely the criterion defining the initiation of motion and the restitution coefficient. Then, a two stacked blocks model is developed and solved by an event-driven strategy. This two-block model is intended to allow a better description of the behaviour of tested specimens through a more precise modelling of the additional mass. Finally, the pres-ence of rubber layers positioned at the top and bottom of two of the tested walls with the pur-pose of improving their acoustic behaviour required the development of an updated rocking model with viscous and flexible interfaces at the base of the wall and between the two stacked blocks. The properties of these interfaces are deduced from experimental data and their sig-nificant influence on the response is evidenced. [less ▲]

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See detailTrace element contamination severity of coastal waters: A first bioassessment at the scale of the whole Mediterranean Sea
Richir, Jonathan ULg; Salivas-Decaux, Maylis; Lafabrie, Céline et al

in PeerJ (2015, May)

Human activities generate large volumes of waste that supply marine coastal environments in pathogens, organic matter, nutrients and toxicants. Among the wide range of toxicants are trace elements. Since ... [more ▼]

Human activities generate large volumes of waste that supply marine coastal environments in pathogens, organic matter, nutrients and toxicants. Among the wide range of toxicants are trace elements. Since the latter are toxic for aquatic organisms from threshold levels and as they are therefore likely to cause multiple damage to the population, the community and the ecosystem levels, their environmental occurrence has to be accurately monitored in order to guarantee appropriate environmental management of coastal zones and to preserve marine coastal ecosystems and the goods and services they provide. In the framework of the STARECAPMED project, the present study aimed to monitor, for the first time, the coastal contamination of the entire Mediterranean by As, Ag, Cd, Cu, Hg, Ni and Pb, using Posidonia oceanica (L.) Delile as bioindicator species. But sustainable coastal management also requires the development of appropriate contamination classification systems intended, among other purposes, for environmental managers and policy makers. The combined utilization of several complementary monitoring tools, i.e. water quality scale, pollution index (TEPI and TESVI) and spatial analysis (PCA, CA, correlation analysis and GIS mapping) successfully led to the development of an operational classification system of this kind. In particular, the mapping of the trace element contamination according to a new proposed 5-level water quality scale using the quantile method precisely outlined the contamination severity along Mediterranean coasts and facilitated interregional comparisons. The reliability of the use of P. oceanica as bioindicator species was further again demonstrated through several global, regional and local detailed case studies. In conclusion, holistic approaches such as developed in the present study should be privileged to accurately monitor the contamination rate of coastal waters and to transfer relevant information on this composite problem to environmental managers and policy makers. [less ▲]

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See detailSeagrasses or caged mussels to bioassess the contamination rate of Mediterranean coastal waters? That is the question
Richir, Jonathan ULg; Galgani, François; Benedicto, José et al

in PeerJ (2015, May)

Biological indicators have the capacity to integrate the temporal changes of contaminants, concentrations or fluxes over various time-scales, and are thus considered as interesting tools for water quality ... [more ▼]

Biological indicators have the capacity to integrate the temporal changes of contaminants, concentrations or fluxes over various time-scales, and are thus considered as interesting tools for water quality biomonitoring. Since the mid-70ies, French programs have developed water monitoring approaches based on the use of bivalve molluscs; and recently the natural background and the extent of water contamination were bioassessed at the scale of the whole western Mediterranean. But even if bivalve molluscs are viewed as reliable bioindicators, their use is not always made easy as a result of their absence in numerous coastal regions that force their transplantation (cages) during several months before their sampling and analysis. This weakness led several scientists to evaluate the bioindicator abilities of other marine organisms. Seagrasses, whose ability to bioaccumulate contaminants proportionally to environmental contamination levels has been clearly demonstrated, have thus been proposed as an appropriate alternative tool for coastal water quality assessment. Very little studies have however so far considered the combined utilization of these two groups of bioindicator organisms, i.e. caged bivalve molluscs and seagrasses. In the framework of the STARECAPMED project, we therefore compared and discussed the bioaccumulation of trace elements in the Neptune grass Posidonia oceanica and in caged Mediterranean mussels Mytilus galloprovincialis. The sampling was performed at the scale of the western Mediterranean. The two species told two contamination stories which, although sometimes different, showed to be complementary. P. oceanica and M. galloprovincialis bioaccumulated dissolved trace elements from the water column and thus provided information regarding trace element contamination severity integrated over several days to a few months. Seagrasses, strongly rooted in the sediments, reflected the long-term exposure to trace elements since sediments offer a degree of time integration over several years to decades. Caged mussels, as filter feeder artificially maintained in the water column, bioaccumulated trace elements from their particulate phase, and therefore gave valuable information regarding continental-terrigenous inputs to coastal waters. In conclusion, seagrasses and mussels should neither supplant, nor substitute, but rather complement each other in order to provide the full time- and space-integrated coastal contamination story of the Mediterranean. [less ▲]

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See detailMapping Posidonia oceanica meadows through time A story of precision, evaluation and fragmentation
Abadie, Arnaud ULg; Jousseaume, Matthieu; Lejeune, Pierre et al

Poster (2015, May)

Over the last decades, the interest in mapping Posidonia oceanica beds has increased along with the improvement of the equipment’s precision of data acquisition. In Calvi Bay (Corsica, France) the meadows ... [more ▼]

Over the last decades, the interest in mapping Posidonia oceanica beds has increased along with the improvement of the equipment’s precision of data acquisition. In Calvi Bay (Corsica, France) the meadows cover an area of about 5 km² and are found at a depth ranging from 3 m to 37 m. The availability of three distinct datasets for 1997, 2002 and 2010 allowed to assess changes in the patchiness of the meadows in the bay and to investigate evolution of maps precision through a surface analysis via GIS software. Thus, three maps were elaborated combining aerial photographs and side scan sonar images. The meadows percentage of cover through time was assessed using four bathymetric sections: 0-10 m, 11-20 m, 21-30 m and 31-40 m. Differences in the patchiness of P. oceanica meadows between 1997 and 2010 appear to be moderate (less than 3 %) in the sections 0-10 m and 11-20 m and then greatly increase with depth: 24 % at 21-30 m and 39 % at 31-40 m. This amazing regression seems hardly natural and unlikely given the slight quantity of human activities that can cause damages on the P. oceanica meadows of the Calvi Bay. These results are likely to be mainly due to the improvement of precision and resolution of the aerial photographs (5 m in 1997, 0.8 m in 2002 and 0.5 m in 2010) and sonar images (5 m in 1997, 3 m in 2002 and 0.5 m in 2010). An issue of habitat determination (human vs instrumental) linked with the method adopted for mapping can also cause differences in the percentage of cover. Given the different accuracy among the three maps, the real regression and fragmentation of P. oceanica meadows could be hardly assessed. However, in several areas where the human activities are important, a clear regression or even a disappearance of the meadows has been observed. It is obvious that the last maps are more accurate than the previous ones and, thus, the former can be used for management purpose as well as for study on the patchiness; however, they still keep uncertainty no matter which method is used to create them. [less ▲]

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See detailSoft bottom macrofauna monitoring under anthropogenic influences in Calvi bay, Corsica: Methodological simplifications
Donnay, Annick ULg

Conference (2015, May)

This work is within the framework of STARE-CAPMED long-term research program of STARESO dedicated to STAtion of Reference and rEsearch on Change of local and global Anthropogenic Pressures on ... [more ▼]

This work is within the framework of STARE-CAPMED long-term research program of STARESO dedicated to STAtion of Reference and rEsearch on Change of local and global Anthropogenic Pressures on Mediterranean Ecosystem Drifts. For the soft-bottom macrofauna topic, fourteen stations are sampled one to two times per year, along gradients from anthropogenic sources of influence (river mouth, fish farm, anchoring areas and sewage) mere 2 stations out of influences. The sorting and analysis of soft-bottom macrofauna is time consuming and some methodological simplifications are looking for. Moreover, an adaptation of the M-AMBI for the weak human impacted geographic zone, the Corsica, is envisaged by a weighting with the Piélou index. As a first time, all is done at the species level. In a second time, the steps are done at genus and family levels. By comparison of results obtained between different identification levels, the taxonomic sufficiency (TS) for the Corsican coastal waters is determined. The adapted M-AMBI calculation and TS are applied on the macrofauna populations identified in Calvi bay. It could be interesting to test the analysis process applied around Corsica on other Mediterranean areas. [less ▲]

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See detailOne-year Prevalence of Migraine Using a Validated Extended French Version of the ID MigraineTM: a Belgian Population-Based Study
Schoenen, Jean ULg; Streel, Sylvie ULg; Donneau, Anne-Françoise ULg et al

in Cephalalgia : An International Journal of Headache (2015, May), 35(6), 155-156

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See detailContribution of diversified farming systems to the delivery of ecosystem services
Boeraeve, Fanny ULg; Dufrêne, Marc ULg; Dendoncker, Nicolas

Conference (2015, May)

The present contribution introduces an innovative research project analyzing farms which have encompassed a transition towards more sustainability. The project being at its premise, we shall focus the ... [more ▼]

The present contribution introduces an innovative research project analyzing farms which have encompassed a transition towards more sustainability. The project being at its premise, we shall focus the presentation on the innovative aspects of the methodology and expected outcomes with a first introduction on the context and the theoretical framework relied on. [less ▲]

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See detailAdapting Nitrogen management to the increasing climatic uncertainty
Dumont, Benjamin ULg; Basso, Bruno; Bodson, Bernard ULg et al

in Shirmohammadi, Adel; Bosch, David; Muñoz-Carpena, Rafa (Eds.) Proceedings of the 1st ASABE Climate Change Symposium - Adaptation and Mitigation (2015, May)

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See detailLarge-scale polarization alignments of quasars in the JVAS/CLASS 8.4-GHz surveys
Pelgrims, Vincent ULg; Hutsemekers, Damien ULg

Poster (2015, May)

We analyse the large sample of polarization measurements of the flat-spectrum radio sources of the JVAS/CLASS 8.4-GHz surveys compiled by Jackson et al. (2007). We tested the uniformity of the ... [more ▼]

We analyse the large sample of polarization measurements of the flat-spectrum radio sources of the JVAS/CLASS 8.4-GHz surveys compiled by Jackson et al. (2007). We tested the uniformity of the polarization position angles for a wide range of angular (2D) and comoving (3D) separations and studied the several subsamples, dividing the main sample of 4155 sources regarding their object type (QSO, galaxies, radio sources,...). We found regions of the sky of about 20 degree radius in which quasars (only) have correlated polarization position angles. Those regions coincide with the regions of alignment at optical wavelength pinpointed in 1998 by Hutsemékers. [less ▲]

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See detailTesting of a Spacecraft Structure with Non-Smooth Nonlinearities
Renson, Ludovic ULg; Noël, Jean-Philippe ULg; Kerschen, Gaëtan ULg

Conference (2015, May)

The dynamics of the SmallSat, a real-life spacecraft possessing a complex isolation device with multiple nonsmooth nonlinearities is investigated. Experiments show that nonlinearities induce modal ... [more ▼]

The dynamics of the SmallSat, a real-life spacecraft possessing a complex isolation device with multiple nonsmooth nonlinearities is investigated. Experiments show that nonlinearities induce modal interactions between modes with non-commensurate linear frequencies. A model of the structure with a simplified description of the nonlinear connections is first built using techniques available in industry. Numerical continuation is then exploited to compute nonlinear normal modes and uncover interaction phenomena that can jeopardize the structural integrity. [less ▲]

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See detailFractured bedrock investigation by using high-resolution borehole images and the Distributed Temperature Sensing technique
Radioti, Georgia ULg; Delvoie, Simon ULg; Radu, Jean-Pol ULg et al

in ISRM Congress 2015 Proceedings - Int’l Symposium on Rock Mechanics (2015, May)

In order to investigate the fracturing of the bedrock and its possible heterogeneous distribution in situ, four boreholes equipped with double-U geothermal pipes of 100 m long were installed on the campus ... [more ▼]

In order to investigate the fracturing of the bedrock and its possible heterogeneous distribution in situ, four boreholes equipped with double-U geothermal pipes of 100 m long were installed on the campus of the University of Liege (Liege, Belgium) over a surface area of 32 m². The bedrock, which starts at a depth approximately of 8 m, is quite fractured and consists mainly of siltstone and shale interbedded with sandstone. Different geophysical methods are applied at two different phases, after drilling the boreholes and after injecting the grouting material. The first approach consists in lowering an ultrasonic borehole imager (borehole televiewer; Zemanek, Glenn, Norton, & Caldwell, 1970), an instrument that acts as an ultrasonic transducer and receiver, into the boreholes to obtain high-resolution, continuous images with 360° coverage of the local geology and fracturing. Moreover gamma-ray logs of the four boreholes are obtained and inclinometry is conducted. After drilling the boreholes fiber optic cables are attached along the pipe loops and the double-U pipes are installed inside the boreholes. Then the grouting material is injected. The second approach consists in measuring the temperature along the fibers by applying the Distributed Temperature Sensing technique (Soto, Sahu, Faralli, Bolognini, Di Pasquale, Nebendahl, & Rueck, 2007). A laser pulse is injected into the optical fiber and the temperature along the fiber is determined by the intensity of Raman stokes and anti-stokes reemitted signals. Temperature evolution is measured during hardening of the grouting material. Local maxima of the temperature curve are probably due to a local lower thermal conductivity and/or a local larger quantity of grouting material due to gathering of fractures. A detailed fracture characterisation (position, opening, orientation, dip angle) is obtained based on the acoustic signal travel time and amplitude. The fractures are characterised by the same dipping and orientation but significantly vary in number and location in the four boreholes, despite the close distance between them. Gamma-ray data and observation of the cuttings during drilling result in rock identification through depth as well as in determination of the layer dipping. The inclination of the four boreholes tends to be perpendicular to the dipping. The combination of the two geophysical methods as presented provides information useful for the hydro-thermo-mechanical behaviour of the bedrock. The contribution of the thermal behaviour of borehole heat exchangers to bedrock investigation will be further studied by conducting Distributed Thermal Response tests (Fujii, Okubo, & Itoi, 2006). During the tests we will measure the temperature variation thanks to the installed fiber optics. These data will allow us to correlate any anisotropic thermal behaviour to the geological characteristics. The available information could be used for a detailed numerical model. [less ▲]

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See detailEpidemiological aspects and genotypic characterization of strains of Microsporum audouinii isolated in the context of a Belgian National survey on anthropophilic tinea
SACHELI, Rosalie ULg; Dekkers, Charlotte; DARFOUF, Rajae ULg et al

Poster (2015, May)

Objectives The last two years, clinical cases of tinea capitis caused by Microsporum audouinii (M. audouinii), have increased in Belgium. To better understand the emergence of this species in the ... [more ▼]

Objectives The last two years, clinical cases of tinea capitis caused by Microsporum audouinii (M. audouinii), have increased in Belgium. To better understand the emergence of this species in the population, the Belgian National Reference Center (NRC) for dermatophytes launched a national survey in 2013. Epidemiological aspects and genotypic characterization of the strains were included. Methods The study was conducted from March 2013 up to February 2014. All Belgian laboratories were asked to send M. audouinii strains isolated from hair to the NRC with a form to fill in including epidemiological informations. The fungal strains were identified by microscopy or ITS sequencing in case of doubt. The genotypic analysis was performed by the DiversiLab® system (bioMérieux) for DNA fingerprinting and analysis. Epidemiological informations were analyzed with the help of a biostatistician. Results Among the collected isolates, 117 strains have been currently confirmed as M. audouinii. Analysis of the epidemiological characteristics of the infected population shows that the main age category concerns 5-9 year-old children (64%, p< 0,0001) with a sex-ratio M/F of 1.97. Data concerning the geographic origin of the family have been obtained in only 33,6% of the cases. It reveals that strains have been mainly isolated from patients with a Belgian nationality (43,6%) suggesting bias in the data collection. The geographic origin of the remaining group includes several African countries such as Congo (20,61%), Guinea (12,8%) and Burundi (5,12%). The genotypic analysis led to the distinction of 6 genotypic variants of M. audouinii. One of these variants was exclusively recovered from South Belgium (11 strains). The major group was composed of 96 strains, well distributed in different Belgium locations. Two other groups of three strains each were close to the major group but the analysis of the spectral superposition showed some differences between these groups. The two last groups were clearly different from the major group but species identification was confirmed by ITS sequencing. Conclusion The results of the genomic analysis by Diversilab, show that several groups of M. audouinii isolates co-exist in Belgium providing evidence of genetic heterogeneity. However, no clear correlation could be established between the appartenance to a group and epidemiological factors, such as the age or ethnical origin. ________________________________________ [less ▲]

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See detailLes réseaux scientifiques du Roi en Belgique
Pirot, Pascal ULg

Conference (2015, April 30)

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See detailFunctions of binary variables
Crama, Yves ULg

Conference (2015, April 29)

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See detailEpidemiological aspects and genotypic characterization of strains of Microsporum audouinii isolated in the context of a Belgian National survey on anthropophilic tinea
SACHELI, Rosalie ULg; Géron, Bénédicte; Dekkers, Charlotte et al

Poster (2015, April 28)

Objectives The last two years, clinical cases of tinea capitis caused by Microsporum audouinii (M. audouinii), have increased in Belgium. To better understand the emergence of this species in the ... [more ▼]

Objectives The last two years, clinical cases of tinea capitis caused by Microsporum audouinii (M. audouinii), have increased in Belgium. To better understand the emergence of this species in the population, the Belgian National Reference Center (NRC) for dermatophytes launched a national survey in 2013. Epidemiological aspects and genotypic characterization of the strains were included. Methods The study was conducted from March 2013 up to February 2014. All Belgian laboratories were asked to send M. audouinii strains isolated from hair to the NRC with a form to fill in including epidemiological informations. The fungal strains were identified by microscopy or ITS sequencing in case of doubt. The genotypic analysis was performed by the DiversiLab® system (bioMérieux) for DNA fingerprinting and analysis. Epidemiological informations were analyzed with the help of a biostatistician. Results Among the collected isolates, 97 strains have been currently confirmed as M. audouinii. Preliminary analysis of the epidemiological characteristics of the infected population shows that the main age category concerns 5-9 year-old children (84%) with a sex-ratio M/F of 1.95. Data concerning the geographic origin of the family have been obtained in only 45.8% of the cases. It reveals that strains have been mainly isolated from patients with a Belgian nationality (77%) suggesting bias in the data collection. The geographic origin of the remaining group (23%) includes several African countries. The genotypic analysis led to the distinction of 3 genotypic variants of M. audouinii. One of these variants was exclusively recovered from South Belgium (11 strains). The major group was composed of 85 strains, well distributed in different Belgium locations. The last group contains only one strain but this strain was significantly different from the two other variants. Conclusion The automated typing DiversiLab® system proved to be an easy and efficient method to investigate the molecular epidemiology of dermatophytes infections. These preliminary results show that, through Belgium, several groups of isolates co-exist for M. audouinii providing evidence of genetic heterogeneity. At this time all epidemiological informations have not yet been assessed while 35 strains of M. audouinii remain to be analysed genotypically to give definitive conclusions. [less ▲]

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See detailWerner Herzog et Alexander Kluge. Regards croisés sur le Nouveau Cinéma Allemand.
Hamers, Jérémy ULg

Conference (2015, April 25)

Alexander Kluge et Werner Herzog sont assurément deux figures antipodiques dans l’histoire du cinéma allemand. L’engagement politique tout d’abord, indissociable de la création audiovisuelle pour le ... [more ▼]

Alexander Kluge et Werner Herzog sont assurément deux figures antipodiques dans l’histoire du cinéma allemand. L’engagement politique tout d’abord, indissociable de la création audiovisuelle pour le premier, objet de méfiance si pas de rejet pour le second, oppose manifestement ces deux figures de proue du Nouveau Cinéma Allemand, un courant dont l’acte de naissance, le manifeste d’Oberhausen de 1962, coïncide avec les débuts cinématographiques des deux auteurs. Leurs esthétiques respectives ensuite confirment le gouffre irréductible qui semble les séparer. Enfin, auteurs l’un et l’autre d’œuvres théoriques sur le cinéma, ils défendent deux approches réflexives de la création audiovisuelle qui apparaissent a priori comme inconciliables. En première lecture, Kluge et Herzog incarnent donc toute l’hétérogénéité bien connue du Nouveau Cinéma Allemand. À rebours de ce constat largement répandu dans les histoires de ce courant cinématographique, et sans pour autant réconcilier les deux auteurs à tout prix, un regard croisé sur quelques-uns de leurs films (e.a. Gelegenheitsarbeit einer Sklavin et Die Artisten in der Zirkuskuppel : ratlos pour Kluge ; Fata Morgana et Fitzcarraldo pour Herzog) et textes (e.a. les écrits d’Ulm de Kluge et la déclaration du Minnesota de Herzog) permet de dégager plusieurs points de rencontre entre les œuvres des deux cinéastes. Partant plus particulièrement de leurs conceptions de la rencontre entre documentaire et fiction, rencontre essentielle pour l’un comme pour l’autre, il s’agira d’en dégager les similitudes et résonances pour mieux comprendre, grâce à un éclairage réciproque, l’une et l’autre de ces œuvres essentielles du cinéma allemand des années soixante, septante et quatre-vingt. [less ▲]

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See detailAge at Retirement: New Proxy of Cognitive Reserve? Results from a French Population-Based Study
Grotz, Catherine ULg; Meillon, Céline; Amieva, Hélène et al

Conference (2015, April 25)

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See detailRetour au travail après un cancer du sein
Mairiaux, Philippe ULg; Schippers, Nathalie ULg; DESREUX, Joëlle ULg et al

Conference (2015, April 23)

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See detailStudy of a new splice variant of Neuropilin-1: antagonistic functions in the regulation of cancer progression?
Hendricks, Céline ULg; Janssen, Lauriane; Delcombel, Romain et al

Poster (2015, April 22)

Neuropilin-1 (NRP1) is a transmembrane glycoprotein and a co-receptor for several growth factors, for example some variants of the Vascular Endothelial Growth Factor A (VEGF-A). It largely contributes to ... [more ▼]

Neuropilin-1 (NRP1) is a transmembrane glycoprotein and a co-receptor for several growth factors, for example some variants of the Vascular Endothelial Growth Factor A (VEGF-A). It largely contributes to the regulation of angiogenesis but also to cancer formation. NRP1 can be considered as a proteoglycan as glycosaminoglycans side chains can be added on serine 612. Currently, six splice variants of NRP1 have been described. An additional form was recently identified in our laboratory. Depending upon the cell types, it represents 20-30% of the total amount of NRP1. As compared to the full size NRP1 (NRP1-FS), 7 amino acids are deleted. As the missing sequence is located 2 amino acids downstream of the Ser612 required for glycosaminoglycans addition, this process could be somehow affected and the function of the protein could be modified. The glycosylation of NRP1-FS and -Δ7 was analyzed in different cells overexpressing each isoform. Western blotting analyses suggested that NRP1-Δ7 was less glycosylated than NRP1-FS. Prostate cancer cells (PC3) were engineered to express NRP1-FS or –Δ7 only in the presence of doxycycline. The migration of these cells was analyzed by scratch assay, with or without doxycycline in the medium. As compared to controls and to NRP1-FS-expressing cells, production of NRP1-Δ7 was linked to a reduction of cell migration. A DNA dosage showed that NRP1-FS enhanced cell proliferation, while NRP1-Δ7 reduced it. Tumor growth was assessed in vitro by a culture in soft agar. As compared to control conditions, expression of NRP1-FS by doxycycline increased colonies formation. By contrast, NRP1-Δ7 inhibited colonies number, suggesting an inhibition of tumorigenesis by this variant. As PC3 cells express basal level of endogenous NRP1, this suggests some competitive inhibition of NRP1 functions by NRP1-Δ7. Finally, the function of each variant was investigated in vivo in a model of injection in the flanks of nude mice of PC3 cells conditionally expressing NRP1-FS or -Δ7. As compared to the control, NRP1-FS increased tumor size and weight. By sharp contrast, the expression of NRP1-Δ7 was associated with a reduction of tumorigenicity. Cells with forced expression of NRP1-Δ7 also developed fewer blood vessels as compared to the control. These results suggest that NRP1-Δ7 have an antagonistic action on cancer formation and angiogenesis. [less ▲]

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See detailDoctors, Nurses and Patients 2.0: Myth or Reality?
Slomian, Cynthia ULg

Conference (2015, April 21)

This communication aims at drawing the general context underlying the Belgian health care sector and to address the key issues of the computerization of the patient health records. Two case studies are ... [more ▼]

This communication aims at drawing the general context underlying the Belgian health care sector and to address the key issues of the computerization of the patient health records. Two case studies are presented: the introduction of a nursing health record within a hospital and the computerization of the general practitioner's record. Finally, the discussion focuses on the medical knowledge in general, using the embodied, inscribed, enacted phenomenology developed by Richard Freeman and Steven Sturdy. [less ▲]

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See detailThermodynamik und Reaktions-Technik am Beispiel PA12
Pfennig, Andreas ULg; Haas, Thomas

Conference (2015, April 18)

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See detailBrazil’s South South Cooperation with Africa : a win win Relationship ? The case of biofuel production in Mozambique
Cusson, Gabrielle ULg

Conference (2015, April 18)

Since Lula’s presidency, South-South development cooperation (SSDC) has been at the heart of Brazil foreign policy priorities. Brazil is now recognized as an emerging actor in international development ... [more ▼]

Since Lula’s presidency, South-South development cooperation (SSDC) has been at the heart of Brazil foreign policy priorities. Brazil is now recognized as an emerging actor in international development cooperation considering its financial investments and the deployment of its many technical cooperation projects. Despite its cooperation in its own region, Brazil mobilizes a considerable amount of resources towards SSDC in Africa, and especially in Portuguese speaking countries, where it develops a “solidarity diplomacy”. Among the many technical cooperation partnerships, two fields of SSDS are considered as priorities for Brazil in Africa; agriculture and biofuels production. Being one of the world most important agricultural producer and exporter and due to the fast growing of its agribusiness industry, Brazil possess a specific expertise he wishes to share with Africa to support its agricultural revolution and to insure its food and energy security. Therefore, Mozambique has been identified as a privileged partner to develop agricultural projects, including biofuels production. Among others, ProSAVANA, a trilateral cooperation project developed in collaboration with Japan, is a very important, but controversial project. Being an emerging country, Brazil has its own strategic, political and commercial interests. Therefore, it is relevant to ask ourselves if an emerging country can deploy a selfless SSDC policy and establish a win win relationship? Is Brazil’s SSDC policy motivated by principles of solidarity or is more of a tool to consolidate its status as a global power? This papers wishes to analyses the real motivations behind Brazil’s SSDC towards Africa. [less ▲]

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See detailLes documents administratifs du recto du P.Vat. Gr. 11
Ricciardetto, Antonio ULg

in Amato, Eugenio; Marganne, Marie-Hélène (Eds.) Le traité "Sur l'exil" de Favorinos d'Arles. Papyrologie, philologie et littérature (2015, April 17)

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See detailTSP model for electric vehicle deliveries, considering speed, loading and path slope.
Bay, Maud ULg; Limbourg, Sabine ULg

Conference (2015, April 17)

In the current Transport White Paper, the European Union presents a roadmap for a more competitive and sustainable European transport system. Concerning Urban Freight Transport, responsible for about a ... [more ▼]

In the current Transport White Paper, the European Union presents a roadmap for a more competitive and sustainable European transport system. Concerning Urban Freight Transport, responsible for about a quarter of CO2 emissions of the transport sector, one of the goals of the EU is to achieve essentially CO2-free city logistics in major urban centres by 2030 by developing and deploying new and sustainable fuels and propulsion systems. The gradual phasing out of ‘conventionally-fuelled’ vehicles from the urban environment contributes to reduce oil dependence, greenhouse gas emissions and local air and noise pollution. To meet European air quality standards, authorities of some major European cities have already introduced Low Emissions Zones where access to urban areas is limited to freight vehicles that meet certain emissions standards. Greater use of low-emission urban trucks based on electric, hydrogen and hybrid technologies would reduce air emissions, but also noise, letting to use road infrastructure more efficiently by making night deliveries and avoiding morning and afternoon peak periods. In addition to their role in the reduction of polluting emissions, the development of low-emission vehicles also allows to mitigate the dependence of the transportation sector to high fossil fuel prices. Electric vehicles have the potential to be powered by renewable energy sources such as wind and solar energy. However, weaknesses can be found in the limited capacity of the battery and the time needed to recharge, and consequently, the limited driving range of electric vehicle. The main sources for final energy consumption are the vehicle size and the engine characteristics, the load factor, the driving pattern, the gradient which represent the average topology of the country, the speed and the acceleration. To maximize the driving range, a routing model, which aims at minimizing the energy consumption, has to be developed. Our paper focus on the Electric Vehicle Traveling Salesman Problem (EV-TSP): given n cities, find the shortest tour, i.e., the shortest directed cycle containing all cities. The classical objective is to minimize the cost tour scheduling to fulfill delivery requests at each location. In this paper we consider the energy cost and we present an extension of the classical problem to minimize the remaining storage capacity of all electric vehicles at the destination node, knowing that there is no recharge operation on the tour. The objective function accounts not just for the travel distance but also on the load of the vehicle and on its speed while the energy consumption of the engine additionally depends on the path to travel, on the slope of the roads and on the vehicle specifications. Moreover, negative consumption that may happen due to regenerative breaking and kinetic energy capture on downhill paths is taken into consideration. Mathematical model is described and computational experiments are performed. [less ▲]

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See detailLire les textes informatifs au début du secondaire : d’un dispositif didactique à l’étude de l’activité des élèves et à l’accompagnement du travail d’appropriation/transformation des enseignants
De Croix, Séverine ULg; Wyns, Marielle

Conference (2015, April 17)

Notre intervention s’appuie sur les premières données issues d’une recherche de type quasi expérimental , subventionnée par la Fondation Louvain (UCL – Louvain-la-Neuve), qui porte sur l’enseignement ... [more ▼]

Notre intervention s’appuie sur les premières données issues d’une recherche de type quasi expérimental , subventionnée par la Fondation Louvain (UCL – Louvain-la-Neuve), qui porte sur l’enseignement, dans l’ordinaire de la classe, des pratiques de lecture et d’écriture des textes informatifs requises pour réussir à l’école (Bautier et Rayou, 2009 ; Crinon, 2011). « Lirécrire pour apprendre » a pour objectifs (1) d’expérimenter, durant deux années scolaires consécutives, un programme didactique conçu comme une réponse à la prise en charge de difficultés langagières que rencontrent de nombreux élèves face aux usages proprement scolaires des écrits documentaires ; (2) de tester la validité de cet outil auprès d’un échantillon constitué de 90 classes de français du premier degré ( Cèbe & Goigoux, 2007) et (3) d’évaluer les conditions d’implémentation et de mise en œuvre du programme (en termes de formation et d’accompagnement des enseignants) les plus à même de favoriser et de maintenir le changement pédagogique (Rowan & Miller, 2007 ; Dumay, 2009). Dans le cadre de cette communication, nous nous proposons de déplier succinctement les difficultés de lecture et d’écriture identifiées en amont de la conception des cinq modules du programme et de présenter les leviers d’action mobilisés au sein de ceux-ci. Le cœur de la contribution portera ensuite sur l’examen de verbalisations et de traces écrites de l’activité des élèves à l’occasion des deux premiers modules du programme mis en œuvre, intitulés « Se familiariser avec les usages des écrits à visée informative, explicative et justificative » et « Sélectionner des informations dans un ou plusieurs texte(s) et les lier entre elles ». Notre analyse des diverses verbalisations générées par ces modules vise la description qualitative de l’activité des élèves en réaction à l’outil pédagogique que nous introduisons et aux supports et documents qu’ils sont amenés à exploiter. Sera également abordée la question de l’appropriation de l’outil par les enseignants. L’examen des verbalisations produites par ces derniers au cours des séances d’accompagnement (dont bénéficient six équipes partenaires) permettra d’observer les écarts et les lieux de convergence entre, d’une part, les pratiques habituelles des enseignants et, d’autre part, les supports et activités proposés par le programme. Nous verrons dans quelle mesure l’implémentation de l’outil didactique dans les classes amène les enseignants à questionner leurs propres postures, à identifier et à mettre en œuvre des gestes professionnels susceptibles de développer chez l’élève des démarches adaptées à la lecture/écriture de textes informatifs. [less ▲]

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See detailLiposomes entrapping apigenin for the treatment of glioblastoma
Karim, Reatul ULg; Palazzo, Claudio ULg; Dubois, Nadège ULg et al

Poster (2015, April 17)

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See detailGlobal, diffuse and direct irradiances modelling over northwestern Europe using regional climate model MAR : validation and construction of a 30-year climatology
Beaumet, Julien ULg; Doutreloup, Sébastien ULg; Fettweis, Xavier ULg et al

Poster (2015, April 17)

Incoming solar global irradiances are modelled using MAR regional climate model forced by ERA-Interim reanalysis. Global irradiances are decomposed into direct and diffuse using sigmoid model from Ruiz ... [more ▼]

Incoming solar global irradiances are modelled using MAR regional climate model forced by ERA-Interim reanalysis. Global irradiances are decomposed into direct and diffuse using sigmoid model from Ruiz-Arias et al. (2010). Results are validated using data from the European Solar Radiation Atlas for Uccle and Braunschweig weather stations. A 30-year climatology has been built and trends and variability have been analyzed. [less ▲]

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See detailSnow cover evolution during the last fifty years in the Hautes Fagnes (Belgium) using the regional climate MAR model
Wyard, Coraline ULg; Fettweis, Xavier ULg; Erpicum, Michel ULg

Conference (2015, April 16)

The MAR model is a regional climate model originally developped for the polar regions to study the surface mass balance. In this study, the MAR model has been adapted to Belgium in order to study the snow ... [more ▼]

The MAR model is a regional climate model originally developped for the polar regions to study the surface mass balance. In this study, the MAR model has been adapted to Belgium in order to study the snow cover evolution of the Hautes Fagnes (south-east of Belgium), a region covered by snow one to two months per year. As validation, we have sucessfully compared MAR based daily snow heights with snowcam-based observations. Then, the model has been forced by ERA-Interim since 1958 to study the snow cover evolution during the last fifty years at the summit of Belgium. The results show non-significant trend. [less ▲]

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See detailGenetic correlations between methane production and milk fatty acid contents of Walloon Holstein cattle throughout the lactation
Vanrobays, Marie-Laure ULg; Vandenplas, Jérémie ULg; Bastin, Catherine ULg et al

Poster (2015, April 16)

Methane (CH4) from ruminal fermentation is the major greenhouse gas produced by dairy cattle which contributes largely to climate change. Production of CH4 also represents losses of gross energy intake ... [more ▼]

Methane (CH4) from ruminal fermentation is the major greenhouse gas produced by dairy cattle which contributes largely to climate change. Production of CH4 also represents losses of gross energy intake. Therefore, there is a growing interest in mitigating these emissions. Acetate and butyrate have common bio-chemical pathways with CH4. Because some milk fatty acids (FA) arise from acetate and butyrate, milk FA are often considered as potential predictors of CH4. However, relationships between these traits remain unclear. Moreover, the evolution of the phenotypic and genetic correlations of CH4 and milk FA across days in milk (DIM) has not been evaluated. The main goal of this study was to estimate genetic correlations between CH4 and milk FA contents throughout the lactation. Calibration equations predicting daily CH4 production (g/d) and milk FA contents (g/100 dL of milk) from milk mid-infrared (MIR) spectra were applied on MIR spectra related to Walloon milk recording. Data included 243,260 test-day records (between 5 and 365 DIM) from 33,850 first-parity Holstein cows collected in 630 herds. Pedigree included 109,975 animals. Bivariate (i.e., CH4 production and one of the FA traits) random regression test-day models were used to estimate genetic parameters of CH4 production and 7 groups of FA contents in milk. Saturated (SFA), short-chain (SCFA), and medium-chain FA (MCFA) showed positive averaged daily genetic correlations with CH4 production (from 0.25 to 0.29). Throughout the lactation, genetic correlations between SCFA and CH4 were low in the beginning of the lactation (0.11 at 5 DIM) and higher at the end of the lactation (0.54 at 365 DIM). Regarding SFA and MCFA, genetic correlations between these groups of FA and CH4 were more stable during the lactation with a slight increase (from 0.23 to 0.31 for SFA and from 0.23 to 0.29 for MCFA, at 5 and 365 DIM respectively). Furthermore, averaged daily genetic correlations between CH4 production and monounsaturated (MUFA), polyunsaturated (PUFA), unsaturated (UFA), and long-chain FA (LCFA) were low (from 0.00 to 0.15). However, these genetic correlations varied across DIM. Genetic correlations between CH4 and MUFA, PUFA, UFA, and LCFA were negative in early lactation (from -0.24 to -0.34 at 5 DIM) and increased afterward to become positive from 15 weeks till the end of the lactation (from 0.14 to 0.25 at 365 DIM). Finally, these results indicate that genetic and, therefore, phenotypic correlations between CH4 production and milk FA vary following lactation stage of the cow, a fact still often ignored when trying to predict CH4 production from FA composition. [less ▲]

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See detailEvaluation of soil structural changes through macroscopic and microscopic measurement
Parvin, Nargish ULg; Degré, Aurore ULg; Chelin, Marie ULg et al

Poster (2015, April 16)

The heterogeneity of soil structure and pore size distribution are highly influenced by external factors like tillage systems and other agricultural management practices. However, changes in soil ... [more ▼]

The heterogeneity of soil structure and pore size distribution are highly influenced by external factors like tillage systems and other agricultural management practices. However, changes in soil hydrodynamic behavior are not fully understood and are still under research. Also, researchers have explained the impact of tillage practices on soil hydraulic properties related to pore size distribution, connectivity and orientation are involved but the characterization of these modifications and consequences remains a challenge. Furthermore, the relation between macroscopic measurements and microscopic investigation of the soil structure remains scarce. Recently, X-ray tomography (X- μCT) has been used in order to characterize changes in soil pore size distribution in various contexts and the method is able to link microtomography information to hydrodynamic measurement. In our study, X-μCT has been used in order to characterize changes in soil pore system. Since, tomography does not count most of the micropores, Richards’ pressure plate and evaporation method was also combined to get complete range of pore size distribution. We found good match between evaporation data with X-μCT at the macropore scale and evaporation data with pressure plate method at micropore scale. X-μCT data refines retention and hydraulic curves near saturation where Richards’ data alone can lead to numerous sets of fitted parameters. On the otherhand, evaporation data (Hyprop apparatus ©) provide comparable datasets with X-μCT. Combining micro and macroscopic measurements allows us to validate X-μCT information, which is otherwise not so obvious. [less ▲]

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See detailRegularized focusing inversion of time-lapse electrical resistivity data: an approach to parametrize the minimum gradient support functional
Nguyen, Frédéric ULg; Hermans, Thomas ULg

Poster (2015, April 15)

Inversion of time-lapse resistivity data allows obtaining ‘snapshots’ of changes occurring in monitored systems for applications such as aquifer storage, geothermal heat exchange, site remediation or ... [more ▼]

Inversion of time-lapse resistivity data allows obtaining ‘snapshots’ of changes occurring in monitored systems for applications such as aquifer storage, geothermal heat exchange, site remediation or tracer tests. Based on these snapshots, one can infer qualitative information on the location and morphology of changes occurring in the subsurface but also quantitative estimates on the degree of changes in certain property such as temperature or total dissolved solid content. Analysis of these changes can provide direct insight into flow and transport and associated processes and controlling parameters. However, the reliability of the analysis is dependent on survey geometry, measurement schemes, data error, and regularization. Survey design parameters may be optimized prior to the monitoring survey. Regularization, on the other hand, may be chosen depending on available information collected during the monitoring. Common approaches consider smoothing model changes both in space and time but it is often needed to obtain a sharp temporal anomaly, for example in fractured aquifers. We here propose to use the alternative regularization approach based on minimum gradient support (MGS) (Zhdanov, 2002) for time-lapse surveys which will focus the changes in tomograms snapshots. MGS will limit the occurrences of changes in electrical resistivity but will also restrict the variations of these changes inside the different zones. A common difficulty encountered by practitioners in this type of regularization is the choice of an additional parameter, the so-called , required to define the MGS functional. To the best of our knowledge, there is no commonly accepted or standard methodology to optimize the MGS parameter . The inversion algorithm used in this study is CRTomo (Kemna 2000). It uses a Gauss-Newton scheme to iteratively minimize an objective function which consists of a data misfit functional and a model constraint functional. A univariate line search is performed at each Gauss-Newton iteration step to find the optimum value of the regularization parameter  which minimizes the data misfit as a function of  while the data misfit is above the desired value and yields the desired target misfit (root-mean square value of error-weighted data misfit equal to 1) at the last iteration for a maximum value of . We propose here to optimize the  of the MGS functional by considering a univariate line search at the first iteration to find the  that minimizes the data misfit. The parameter is then kept constant during the Gauss-Newton iterative scheme. In this contribution, we validate our approach on a numerical benchmark and apply it successfully on a case study in the context of salt tracers in fractured aquifers. Zhdanov M.S. 2002. Geophysical Inverse Theory and Regularization Problems. Elsevier, Amsterdam, 628 p. Kemna A. 2000. Tomographic Inversion of Complex Resistivity - Theory and Application. PhD Thesis, Ruhr University Bochum. [less ▲]

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See detailVariogram-based inversion of time-lapse electrical resistivity data: development and application to a thermal tracing experiment
Hermans, Thomas ULg; Nguyen, Frédéric ULg

Poster (2015, April 15)

Electrical resistivity tomography (ERT) has become a popular imaging methodology in a broad range of applications given its large sensitivity to subsurface parameters and its relative simplicity to ... [more ▼]

Electrical resistivity tomography (ERT) has become a popular imaging methodology in a broad range of applications given its large sensitivity to subsurface parameters and its relative simplicity to implement. More particularly, time-lapse ERT is now increasingly used for monitoring purposes in many contexts such as water content, permafrost, landslide, seawater intrusion, solute transport or heat transport experiments. Specific inversion schemes have been developed for time-lapse data sets. However, in contrast with static inversions for which many techniques including geostatistical, minimum support or structural inversion are commonly applied, most of the methodologies for time-lapse inversion still rely on non-physically based spatial and/or temporal smoothing of the parameters or parameter changes. In this work, we propose a time-lapse ERT inversion scheme based on the difference inversion scheme. We replace the standard smoothness-constraint regularization operator by the parameter change covariance matrix. This operator takes into account the correlation between changes in resistivity at different locations through a variogram computed using independent data (e.g., electromagnetic logs). It may vary for subsequent time-steps if the correlation length is time-dependent. The methodology is first validated and compared to the standard smoothness-constraint inversion using a synthetic benchmark simulating the injection of a conductive tracer into a homogeneous aquifer inducing changes in resistivity values of known correlation length. We analyze the influence of the assumed correlation length on inversion results. Globally, the method yields better results than the traditional smoothness constraint inversion. Even if a wrong correlation length is assumed, the method performs as well as the smoothness constraint since the regularization operator balances the weight given to the model constraint functional in the objective function. Then the methodology is successfully applied to a heat injection and pumping experiment in an alluvial aquifer. The comparison with direct measurements in boreholes (temperature loggers and distributed temperature sensing optic fibres) shows that ERT-derived temperatures and breakthrough curves image reliably the heat plume through time (increasing part of the curve, maximum and tail are correctly retrieved) and space (lateral variations of temperature are observed) with less spatial smoothing than standard methods. The development of new regularization operators for time-lapse inversion of ERT data is necessary given the broad range of applications where ERT monitoring is used. In many studies, independent data are available to derive geostatistical parameters that can be subsequently used to regularize geophysical inversions. In the future, the integration of spatio-temporal variograms into existing 4D inversion schemes should further improve ERT time-lapse imaging. [less ▲]

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See detailFirst evidence of Neandertal cannibalism in Northern Europe: the case of the “Troisieme Caverne” of Goyet (Belgium)
Rougier, H.; Crevecoeur, I.; Beauval, C. et al

Conference (2015, April 15)

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See detailUse of NIR Hyperspectral Imaging and dichotomist classification tree based on SVM in order to discriminate roots and crop residues of winter wheat
Eylenbosch, Damien ULg; Fernández Pierna, Juan Antonio; Baeten, Vincent et al

Poster (2015, April 14)

NIR Hyperspectral Imaging coupled with SVM chemometric tool is proposed as an alternative method to the tedious and time-consuming hand sorting step needed before root quantification using the soil coring ... [more ▼]

NIR Hyperspectral Imaging coupled with SVM chemometric tool is proposed as an alternative method to the tedious and time-consuming hand sorting step needed before root quantification using the soil coring method. This method was applied to quantify roots under a winter wheat crop. [less ▲]

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See detailLIPOSOME CONTAINING ESTETROL FOR THE TREATMENT OF ISCHEMIA DISEASES IN PREMATURE BABIES
Palazzo, Claudio ULg; Karim, Reatul ULg; Mawet, Mawet et al

Poster (2015, April 14)

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See detailUse of NIR-HIS and dichotomist classification tree based on SVMDA models in order to discriminate roots and crop residues of winter wheat
Eylenbosch, Damien ULg; Fernández Pierna, Juan Antonio; Baeten, Vincent et al

in EARSeL 2015: 9th EARSeL SIG Imaging Spectroscopy workshop, Luxembourg 14-16 April 2015 (2015, April 14)

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See detailFuture projections of the Greenland ice sheet mass balance using the regional climate MAR model coupled with the GRISLI ice sheet model
Wyard, Coraline ULg; Fettweis, Xavier ULg; Ritz, Catherine

Poster (2015, April 14)

During the two last decades, the Greenland ice sheet (GrIS) contribution to the global mean sea level rise has significantly increased. But, difficulties remain to assess GrIS future contribution because ... [more ▼]

During the two last decades, the Greenland ice sheet (GrIS) contribution to the global mean sea level rise has significantly increased. But, difficulties remain to assess GrIS future contribution because of large uncertainties linked to the feedback between the surface mass balance (SMB) and GrIS topography changes. The regional climate MAR model has been coupled with the GRISLI ice sheet model, in order to account of this feedback in the future projections. The aim of this study is to assess the pertinence of the MAR-GRISLI coupling which requires long computation time. In order to identify GRISLI sensitivity to MAR forcing, GRISLI has been forced with various non-coupled (i.e. using a fixed topography), coupled and modified non-coupled MAR outputs. To adapt the non-coupled MAR outputs to the GRISLI topography changes, we use an interpolation technique based on SMB vs elevation vertical gradient. These experiences evaluate the performances/limits of this interpolation technique used to avoid a RCM-ice sheet model coupling. [less ▲]

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See detailEGU2015 - ENSO forecast using a wavelet-based mode decomposition
Deliège, Adrien ULg; Nicolay, Samuel ULg; Fettweis, Xavier ULg

Conference (2015, April 13)

The aim of this work is to introduce a new method for forecasting major El Niño/ La Niña events with the use of a wavelet-based mode decomposition. These major events are related to sea surface ... [more ▼]

The aim of this work is to introduce a new method for forecasting major El Niño/ La Niña events with the use of a wavelet-based mode decomposition. These major events are related to sea surface temperature anomalies in the tropical Pacific Ocean: anomalous warmings are known as El Niño events, while excessive coolings are referred as La Niña episodes. These climatological phenomena are of primary importance since they are involved in many teleconnections ; predicting them long before they occur is therefore a crucial concern. First, we perform a wavelet transform (WT) of the monthly sampled El Niño Southern Oscillation 3.4 index (from 1950 to present) and compute the associated scale spectrum, which can be seen as the energy carried in the WT as a function of the scale. It can be observed that the spectrum reaches five peaks, corresponding to time scales of about 7, 20, 31, 43 and 61 months respectively. Therefore, the Niño 3.4 signal can be decomposed into five dominant oscillating components with time-varying amplitudes, these latter being given by the modulus of the WT at the associated pseudo-periods. The reconstruction of the index based on these five components is accurate since more than 93% of the El Niño/ La Niña events of the last 60 years are recovered and no major event is erroneously predicted. Then, the components are smoothly extrapolated using polynomials and added together, giving so several years forecasts of the Niño 3.4 index. In order to increase the reliability of the forecasts, we perform several months hindcasts (i.e. retroactive probing forecasts) which can be validated with the existing data. It turns out that most of the major events can be accurately predicted up to three years in advance, which makes our methodology competitive for such forecasts. Finally, we discuss the El Niño conditions currently undergone and give indications about the next La Niña event. [less ▲]

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See detailRecent increase of ethane detected in the remote atmosphere of the Northern Hemisphere
Franco, Bruno ULg; Bader, Whitney ULg; Bovy, Benoît ULg et al

Conference (2015, April 13)

Ethane (C2H6) has a large impact on tropospheric composition and air quality because of its involvement in the global VOC (volatile organic compound) – HOx – NOx chemistry responsible for generating and ... [more ▼]

Ethane (C2H6) has a large impact on tropospheric composition and air quality because of its involvement in the global VOC (volatile organic compound) – HOx – NOx chemistry responsible for generating and destroying tropospheric ozone. By acting as a major sink for tropospheric OH radicals, the abundance of C2H6 influences the atmospheric content of carbon monoxide and impacts the lifetime of methane. Moreover, it is an important source of PAN, a thermally unstable reservoir for NOx radicals. On a global scale, the main sources of C2H6 are leakage from the production, transport of natural gas loss, biofuel consumption and biomass burning, mainly located in the Northern Hemisphere. Due to its relatively long lifetime of approximately two months, C2H6 is a sensitive indicator of tropospheric pollution and transport. Using an optimized retrieval strategy (see Franco et al., 2014), we present here a 20-year long-term time series of C2H6 column abundance retrieved from ground-based Fourier Transform InfraRed (FTIR) solar spectra recorded from 1994 onwards at the high-altitude station of Jungfraujoch (Swiss Alps, 46.5° N, 3580 m a.s.l.), part of the Network for the Detection of Atmospheric Composition Change (NDACC, see http://www.ndacc.org). After a regular 1994 – 2008 decrease of the C2H6 amounts, which is very consistent with prior major studies (e.g., Aydin et al., 2011; Simpson et al., 2012) and our understanding of global C2H6 emissions, trend analysis using a bootstrap resampling tool reveals a C2H6 upturn and a statistically-significant sharp burden increase from 2009 onwards (Franco et al., 2014). We hypothesize that this observed recent increase in C2H6 could affect the whole Northern Hemisphere and may be related to the recent massive growth in the exploitation of shale gas and tight oil reservoirs. This hypothesis is supported by measurements derived from solar occultation observations performed since 2004 by the Atmospheric Chemistry Experiment – Fourier Transform Spectrometer (ACE-FTS) instrument and at other NDACC sites, namely Toronto (44° N) and Thule (77° N). Indeed, the recent rates of changes characterizing these data sets are consistent in magnitude and sign with the one derived from the FTIR measurements at Jungfraujoch. In contrast, the ethane time series form Lauder (45° S) shows a monotonic decrease over the last two decades. Investigating both the cause and impact on air quality of the C2H6 upturn should be a high priority for the atmospheric chemistry community. [less ▲]

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See detailPreliminary results for a hydrogen maser cavity in the TE111 mode
Van Der Beken, Emeline ULg; Léonard, Daniel; Counet, Arnaud et al

Poster (2015, April 13)

An analysis of a hydrogen maser working with an unusual TE111 mode is presented. Different simulations have been carried out and are compared with preliminary results obtained for such a maser. In ... [more ▼]

An analysis of a hydrogen maser working with an unusual TE111 mode is presented. Different simulations have been carried out and are compared with preliminary results obtained for such a maser. In contrast to standard hydrogen maser that exploits the TE011 mode, the TE111 mode allows one to design hydrogen masers with significant reduced dimensions which represents a huge benefit for space applications and in particular for the global positioning system. [less ▲]

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See detailSoil porosity in agricultural context: A review of measurement techniques at various scales
Garré, Sarah ULg; Chelin, Marie ULg; Luong, Jeanne ULg et al

Poster (2015, April 13)

Soil compaction was identified by European Commission as one of the eight main threats for agricultural soils. In order to address this issue, measurements of soil porosity are critical. However, there ... [more ▼]

Soil compaction was identified by European Commission as one of the eight main threats for agricultural soils. In order to address this issue, measurements of soil porosity are critical. However, there are as many techniques to measure as there are definitions of porosity. A single method is not sufficient to obtain a complete image of the soil porosity at various scales and encompassing different levels of complexity. Each existing method is characterized by a unique combination of a specific level of complexity, resolution and scale of measurement. In this review, we started by defining the basic terms linked to soil porosity in an agricultural context. Then we give an overview of relevant measurement techniques, from classical methods to recent advances. We present their advantages and disadvantages, the scales of measurement, the resolution, the expected accuracy and the susceptibility to errors. This work aims at guiding the choice for the best (combination of) technique(s) to answer questions related to agricultural soil porosity, categorizing techniques according to the parameters they focus on: from total porosity over pore size distribution, structure and connectivity up to the quantification of spatio-temporal dynamics. [less ▲]

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See detailRetrieval of ammonia from ground-based FTIR measurements and its use for validation of satellite observations by IASI
Dammers, E; Palm, M; Warneke, T et al

in Geophysical Research Abstracts (2015, April 13), 17

Atmospheric Ammonia (NH3) has a major impact on human health and ecosystem services and plays a major role in the formation of aerosols [Erisman et al.,2013; Paulot and Jacob 2014]. NH3 concentrations are ... [more ▼]

Atmospheric Ammonia (NH3) has a major impact on human health and ecosystem services and plays a major role in the formation of aerosols [Erisman et al.,2013; Paulot and Jacob 2014]. NH3 concentrations are highly variable in space and time with overall short lifetime due to deposition and aerosol formation. The global atmospheric budget of nitrogen and in turn NH3 is still uncertain which asks for more ground-based and satellite observations around the world. Recent papers have described the possibility to measure NH3 with satellite infrared sounders which open up the way for calculations of global and regional nitrogen budgets [Clarisse et al 2009,Van Damme et al 2014a]. Validation of the satellite observations is essential to determine the uncertainty in the signal and its potential use. So far available surface layer observations of atmospheric NH3 concentrations have been used for comparisons with total columns retrieved from satellite observations [Van Damme 2014b]. We developed a retrieval for NH3 column density concentrations (molecules NH3/cm2) by fitting a set of spectral windows to ground-based solar absorption Fourier transform infrared (FTIR) measurements with the spectral fitting program SFIT4 [Hase et al., 2004]. The retrieval is then applied to FTIR measurements from a set of spectrometer sites from the Network for detection of Atmospheric Composition Change (NDACC) to retrieve NH3 columns for the sites located in Bremen, Germany; Lauder, New Zealand; Jungfraujoch, Switzerland; and the island of Reunion, France. Using eight years (2005-2013) of retrieved NH3 columns clear seasonal cycles are observed for each of the stations. Maximum concentrations can be related to NH3 emission sources, specific for the regions. A comparison between the retrieved NH3 columns and observations from the recent IASI- NH3 product [Van Damme et al, 2014a] using strict spatial and temporal criteria for the selection of observations showed a good correlation (R=0.82; slope=0.63). The IASI- NH3 columns for the Bremen and Lauder area show similar temporal cycles when compared to the FTIR observations. [less ▲]

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See detailHalogenated source gases measured by FTIR at the Jungfraujoch station: updated trends and new target species
Mahieu, Emmanuel ULg; Bader, Whitney ULg; Bovy, Benoît ULg et al

in Geophysical Research Abstracts (2015, April 13), 17

In this contribution, we present decadal time series of halogenated source gases monitored at the high altitude station of the Jungfraujoch (46.5°N, 8°E, 3580 m asl) with Fourier Transform Infared (FTIR ... [more ▼]

In this contribution, we present decadal time series of halogenated source gases monitored at the high altitude station of the Jungfraujoch (46.5°N, 8°E, 3580 m asl) with Fourier Transform Infared (FTIR) spectrometers, within the framework of the Network for the Detection of Atmospheric Composition Change. Total column trends presented in previous studies for CFC-11, -12 and HCFC-22, CCl4, HCFC-142b, CF4 and SF6 will be updated using the latest available Jungfraujoch solar observations. Investigations dealing with the definition of approaches to retrieve additional halogenated source gases from FTIR spectra will also be evoked. Our trend results will be critically discussed and compared with measurements performed in the northern hemisphere by the in situ networks. [less ▲]

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See detailA short dive into the complexity of Jupiter’s aurorae - invited
Bonfond, Bertrand ULg

Conference (2015, April 13)

Aurorae are the atmospheric signatures of energetic processes taking place far in the magnetosphere. One of the most important results brought by high resolution imaging of the UV aurorae at Jupiter is ... [more ▼]

Aurorae are the atmospheric signatures of energetic processes taking place far in the magnetosphere. One of the most important results brought by high resolution imaging of the UV aurorae at Jupiter is the realization that there isn’t such a thing as «the aurora» at Jupiter; as these light emissions appear to arise from a variety of processes. Some are related to the interaction of the magnetospheric plasma with the moons (the satellite footprints). Others are linked with the radial motion of flux tubes through centrifugal instabilities (the injection auroral signatures). Some diffuse emissions are connected with wave-particle interaction (the equatorward diffuse emissions). Another feature is associated with the magnetosphere-ionosphere coupling (the main emission/oval). Some auroral spots are related to internally driven reconnection (the polar dawn spots). Finally, the polar-most emissions remain to be understood and this list is still incomplete. In order to illustrate the discrepancies between these various features, I will show a set of recent results derived from the analysis of Hubble Space Telescope observations. For example, I will compare the vertical profile of satellite footprints and the main emissions, and show that the energy population of the precipitating particles varies from feature to feature. Moreover, even within a single feature, spatial variations do exist. As an example, I will characterize the dawn-dusk brightness discrepancy of the main emissions and discuss its implication regarding the magnetospheric currents. And finally, the dynamics of the features also helps differentiating one type of aurora from another. This will be shown through the description of the morphological evolution of the transient flares in the polar region. [less ▲]

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See detailWhat is the professional profile of patients in phoniatrics?
Remacle, Angélique ULg; Petitfils, Cloé; LEJEUNE, LIONEL ULg et al

Conference (2015, April 10)

Objective. Research has paid increased attention to occupational voice disorders. This study describes the occupational status of patients examined in the Department of Otorhinolaryngology at Liège ... [more ▼]

Objective. Research has paid increased attention to occupational voice disorders. This study describes the occupational status of patients examined in the Department of Otorhinolaryngology at Liège University Hospital (Belgium) from 2009 to 2013. Study design. Retrospective study. Methods. The sex, age, diagnosis and occupational status were identified for 1,079 patients who were examined for a voice problem (754 women and 325 men; ages 4 to 93). The diagnosis was established using videolaryngostroboscopy. For patients who were employed, we identified (1) the numerically most frequent professionals, and (2) the professionals most at risk of consulting for their voice, based on the distribution of these professions among all workers living in French-speaking Belgium. Results. 11% of patients were unemployed, 15% were students, 20% were retired, and 54% were workers. In decreasing order of frequency, the most commonly seen professionals were teachers, office workers, artists (singers, actors, and musicians), storekeepers and marketing representatives, managers, domestic workers, and laborers. Regarding their distribution in the working population, the workers at greatest risk of consulting were artists, music teachers, counselors, sports coaches, psychologists, switchboard operators, journalists, and teachers. Nodules are the most common pathologies, encountered in 16.8% of the workers and 42.8% of the students who consulted the Department of Otorhinolaryngology for dysphonia. Conclusion. Prevention is needed both for the professions that seek medical help in the largest numbers (teachers) and for those that are at highest risk of consulting (artistic professions). In addition, teachers must be informed of the need to seek help as soon as voice problems appear. Level of evidence: 2b [less ▲]

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See detailEstimated Subglottic Pressure Evaluation, Evolution in 152 Dysphonic Patients
Morsomme, Dominique ULg; Finck, Camille ULg; Larrouy, Pauline ULg

Conference (2015, April 08)

Background: Estimated subglottic pressure (ESGP) is part of the aerodynamic measurements included in the vocal profile. It is an indication of vocal effort. Speyer reports an improvement of the ESGP score ... [more ▼]

Background: Estimated subglottic pressure (ESGP) is part of the aerodynamic measurements included in the vocal profile. It is an indication of vocal effort. Speyer reports an improvement of the ESGP score after voice treatment. Nevertheless, few studies used ESGP to evaluate voice efficiency treatment. Objectives: The purpose is to examine the ESGP twice, at the first (T1) and the last consultation (T2) . We observe the ESGP values according to voice pathology. We also examine the relationships between ESGP, SPL(Sound pressure level) and DSI (Discorder severity index) . Method: The study includes 130 patients (M:31/W:99), which suffer from 4 different pathologies as immobility (N: 54), oedema (N:23), nodules (N:24) and polyp (N:29). Each patient’s file consists of VLS, acoustic, aerodynamic and perceptual measures. The ESGP was collected through the Phonatory Aerodynamic System Model 6600 (KayPentax). Patients produced 3 sequences of / ipipi / at low (IL), conversational (IC) and high (IH) intensity. Patients were grouped according to the ENT’s diagnosis. We compare our values to those of Zraick et al (2012) which studied ESGP on a healthy group. Results: At T2, for the all patients, at minimum and conversational intensity the ESGP scores decrease singificantly, even if those scores were higher than for the healthy group. We observe a negative correlation between ESGP and SPL at low and conversational intensity. At T1, the higher is the ESGP score, the lower is the SPL score. At T2, the higher is the ESGP score, the higher is the SPL score. At T1, a negative correlation is observed between ESGP and DSI for 2 groups of patients (immobility and polyp) only at minimum intensity. The higher is the ESGP, the lower is SPL. At T2, only for the group immobility, the negative correlation persists. Conclusion: This study highlights the importance of considering the ESGP as a parameter of efficiency. High ESGP is mainly connected with patients who suffer from pathology. The patient who suffer from immobility seems to present a specific profile which could help the clinician to better understand their vocal behavior. Recommendation: This study highlights the pertinence of considering the ESGP as a parameter of vocal treatment efficiency. [less ▲]

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See detailState of the art on drivers of deforestation in the Congo basin tropical forest
Gillet, Pauline ULg; Vermeulen, Cédric ULg; Dessard, Hélène et al

Conference (2015, April 07)

The Congo basin forest experiment a low pressure on biodiversity in comparison to other rainforests around the world. But according to the predictions, climate change and direct human drivers could have ... [more ▼]

The Congo basin forest experiment a low pressure on biodiversity in comparison to other rainforests around the world. But according to the predictions, climate change and direct human drivers could have an important effect on the deforestation rate. In that context, CoForTips project want to foster a better management of the Congo Basin forests through a better understanding of the dynamics, regime shifts and tipping points of biodiversity and a better definition of the conditions of resilience of social and ecological systems. In order to assess the current knowledge about drivers of deforestation in the world tropical forests, we analyzed the existent literature to list the direct and indirect drivers of deforestation in the forested tropical zones and to focus on deforestation in the Congo Basin forest and specifically in Cameroon and Gabon. We listed direct drivers of deforestation like expansion of agriculture which can be either family farming or agribusiness; timber extraction for softwood industry and fuel wood; development of infrastructure leading to the opening up of forested land and populations, and mining industries. The underlying causes found in the literature concern economic factors like gross domestic product, national income based on environmental resources exploitation and consumer demand expressing on local and global markets. Technological factors that allow much larger removal. Cultural issues like representation of the forest in the collective imagination as an important source of economic income. Institutional factors like policy measures advocating pro-deforestation measures and demographic causes taking into account for local population rise due to a high fertility rate and linked to population migration. Those direct and underlying causes of deforestation where then detailed for Cameroon and Gabon. [less ▲]

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See detailLire le futur du passé: villes et paysages de Meuse en projet
Occhiuto, Rita ULg

Conference (2015, April 03)

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See detailTree models with Scikit-Learn: Great models with little assumptions
Louppe, Gilles ULg

Conference (2015, April 03)

This talk gives an introduction to tree-based methods, both from a theoretical and practical point of view. It covers decision trees, random forests and boosting estimators, along with concrete examples ... [more ▼]

This talk gives an introduction to tree-based methods, both from a theoretical and practical point of view. It covers decision trees, random forests and boosting estimators, along with concrete examples based on Scikit-Learn about how they work, when they work and why they work. [less ▲]

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See detailApplication of stable isotopes in trophic ecology: importance of TEF and seasonal baseline for robust interpretations.
Remy, François ULg; Darchambeau, François ULg; Dauby, Patrick ULg et al

Conference (2015, April 02)

Nitrogen, carbon and sulfur stable isotopes are very powerful tools for trophic ecologists to delineate food webs of various ecosystems. More recently… the use of mixing models has exponentially increased ... [more ▼]

Nitrogen, carbon and sulfur stable isotopes are very powerful tools for trophic ecologists to delineate food webs of various ecosystems. More recently… the use of mixing models has exponentially increased to give a more specific vision of organism’s diets and trophic relationships. Two case studies will be presented to give a summary of what’s been done in Liège Oceanology Lab to improve our interpretation of stable isotopes results. First is an experimental calculation of the Trophic Enrichment Factors (TEFs) for one dominant detritivorous species of Mediterranean amphipod inhabiting seagrass detritus: Gammarus aequicauda (Martynov, 1931). This experimental study was planned after a strange result of the SAIR mixing model, giving results opposed to all observations and knowledge we had about this species. Thus, the impact of 3 very different food sources (amphipod powder, algae power, seagrass powder) on the turnover rate of C and N isotopic compositions was tested, and afterwards TEFs for C and N for each source were calculated. Animal food source showed to be the most effectively assimilated with a fast turnover rate while seagrass and algae showed very slow assimilation. TEFs calculations showed to be interesting because TEFs seem not to depend on the natural feeding type of the invertebrate but more on the type of food source. Animal source showed carnivorous TEFs values while seagrass and algae source showed typical detritivorous values. SIAR results with these new custom values gave more coherent values highlighting the major importance of TEFs values for mixing models data interpretation. Second is a simple question: are the seasonal isotopic composition variations observed for many seagrass detritus macrofauna species due to actual diet changes, or only to isotopic baseline shift of the food sources? Macrofauna and all potential food sources were sampled near STARESO Oceanographic Station (Corsica, 8°45’E; 42°35’N) in 2011-2012 at each season at two different sites. SIBER software runs with C and N isotopic data showed spatio-temporal isotopic variations at community, interspecific and intraspecific level. SIBER did not gave us information about the origin of these changes, but coupled with SIAR and our custom TEFs, species actually showing drastic changes of diet were identified, while others seem to reflect more a source baseline isotopic composition shift. Working at specific level is compulsory for fine conclusions. These two case studies highlight the importance of mixing model use and of accurate TEF values to run these models properly to draw robust and reliable conclusions using stable isotopic data. [less ▲]

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See detailDoes high school program choice affect academic performance? Evidence for Economics
Lefevre, Mélanie ULg

Conference (2015, April 02)

This study evaluates the impact of the choice of the Economics elective course in secondary school on the performance in Economics at the University level. While several studies look at the impact on ... [more ▼]

This study evaluates the impact of the choice of the Economics elective course in secondary school on the performance in Economics at the University level. While several studies look at the impact on performance of the number of hours of mathematics in secondary school, less has been made regarding the impact of the secondary school Economics program. We match survey data from 360 students enrolled in the first year of the bachelors program in HEC-Management School of University of Liège, with administrative data and exam results. The methodological challenge is that students who choose Economics elective course in secondary school are likely to be different, in terms of motivation, from other students. To get rid of this potential bias, we approximate motivation using self-reported reasons for the choice of the elective courses, but also participation to non-mandatory tests and preparations before the exam. We also control for several individual characteristics (socio-economic background, age, gender, secondary school fixed effect, etc.) in order to compare students with similar abilities. Preliminary analysis shows that students who have chosen Economics elective course in the last year of secondary school do not perform better, or worse, at their University Economics exam, when controlling for the number of hours of mathematics they had in secondary school, as well as other individual characteristics. However, they are less likely to report their bachelor Economics course as being “difficult”. Overconfidence of students with higher previous economic knowledge may explain why they do not perform better than their peers. [less ▲]

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See detailMultitasking abilities in persons diagnosed with schizophrenia: a new tool and cognitive model.
Laloyaux, Julien ULg; Van der Linden, Martial ULg; Laroi, Frank ULg

Poster (2015, April 01)

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular during multitasking activities (Semkovska et al., 2010). Multitasking refers to ... [more ▼]

Difficulties in everyday life activities are core features of persons diagnosed with schizophrenia, and in particular during multitasking activities (Semkovska et al., 2010). Multitasking refers to activities (e.g. preparing a meal) where the person has to: (a) carry out and alternate between different tasks that vary in terms of priority, difficulty and duration; (b) define the tasks’ targets; (c) and where the person is faced with unexpected problems during the realization of these tasks (Burgess, 2000). However, the cognitive underpinnings of multitasking abilities have never been adequately explored in schizophrenia. Further, only two cognitive models exist in the literature, which are based on student (Logie et al., 2011) and neurological (Burgess et al., 2000) samples. Both of these models suggest three primary constructs: Memory, Planning and Intent. There are, however, several limitations related to the way multitasking abilities were evaluated in these studies. We thus developed a computerized real-life activity task - the Computerized Meeting Preparation Task (CPMT), which was specifically designed to take into account the multitasking nature of certain everyday life activities. Using this task, and based on previous studies (Burgess et al., 2000; Logie et al., 2011), the aim of the present study was to evaluate multitasking abilities in schizophrenia and to do so in a new cognitive model of multitasking that takes into account certain cognitive functions that are not integrated in existing models. Methods: Fifty-seven individuals with schizophrenia and 41 matched healthy controls completed the CMPT. Participants were also evaluated with a battery of cognitive tests. Results: The results suggest that the CMPT possesses good sensitivity and confirmed the three underlying constructs of multitasking (Memory, Planning and Intent), which were found to be underpinned by several cognitive functions and multitasking aspects. Conclusion: Taken together, this new cognitive model and the CMPT could be a good basis for cognitive interventions of multitasking abilities in schizophrenia. Burgess, P.W., 2000. Strategy application disorder: the role of the frontal lobes in human multitasking. Psychol Res 63, 279-288. Logie, R., et al., 2011. Multitasking: multiple, domain-specific cognitive functions in a virtual environment. Mem Cogn 39, 1561-1574. Semkovska, M. et al., 2004. Assessment of executive dysfunction during activities of daily living in schizophrenia. Schizophr Res 69, 289-300. [less ▲]

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See detailAssociation of classical microbiology and 16S rDNA metagenetic Aanalysis to evaluate the presence of Clostridium difficile ina a belgian nursing home
Rodriguez Diaz, Cristina ULg; Taminiau, Bernard ULg; Avesani, Véronique et al

Poster (2015, April 01)

Increasing age, several co-morbidities, environmental contamination, antibiotic exposure and other intestinal perturbations appear to be the greatest risk factors for C. difficile infection (CDI ... [more ▼]

Increasing age, several co-morbidities, environmental contamination, antibiotic exposure and other intestinal perturbations appear to be the greatest risk factors for C. difficile infection (CDI). Therefore, elderly care home residents are considered particularly vulnerable to CDI. The main objective of this study was to evaluate and follow the prevalence of C. difficile in a Belgian nursing home. During a 4-month period, stool samples from a group of 23 elderly care home residents were collected weekly. A C. difficile microbiological detection scheme was performed along with an overall microbial biodiversity study of the faeces content by Targeted Metagenomic analysis. Culture of samples was performed in a selective medium cycloserine cefoxitin fructose cholate. An identification of the isolated colonies was done by PCR detection of tpi, tcdA, tcdB and cdtA genes. Toxic activity was confirmed by a cytotoxic immunoassay. Further characterization was performed by PCR ribotyping. The Metagenomic analysis was targeted on the v1-v3 hyper-variable region of 16S rDNA. The taxonomical assignment of the populations was performed with MOTHUR and Blast algorithms. Seven out of 23 (30.4%) residents were (at least one week) positive for C. difficile. The most common PCR-ribotype identified was 027. Targeted Metagenomic analyses reveals that each resident has his own bacterial imprint, which is stable during the entire study. Residents’ positives for C. difficile by classical microbiology showed an important proportion of C. difficile sequences. However, Metagenomics analysis can’t substitute targeted protocols. It was not used as a diagnostic tool to detect C. difficile but rather to determine the identification and correlations of the major bacterial populations that are present in the gut microbiota. In conclusion, this unique association of classical microbiology protocol with pyrosequencing allowed to follow C. difficile in patients and to identify several other bacterial populations whose abundance is correlated with C. difficile. [less ▲]

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See detailLes voix du lecteur dans la presse française au XIXe siècle: introduction et conclusions
Stienon, Valérie ULg; Absalyamova, Elina

Conference (2015, April)

Le XIXe siècle est assurément l’âge de la lecture. Traversé par un double mouvement d’alphabétisation et de croissance démographique, il voit le lectorat s’étendre à de nouvelles catégories de personnes ... [more ▼]

Le XIXe siècle est assurément l’âge de la lecture. Traversé par un double mouvement d’alphabétisation et de croissance démographique, il voit le lectorat s’étendre à de nouvelles catégories de personnes : ouvriers, femmes, enfants. Dans les foyers, les cafés, les cercles et les cabinets de lecture, c’est l’imprimé à diffusion périodique qui attire à lui l’essentiel de ce nouveau public. Le journal offre une alternative majeure au livre, moins coûteuse et plus accessible. Plus immédiate, aussi, puisqu’il construit avec ses destinataires un système d’adresses et de réponses autour de l’actualité socioculturelle. Du courrier des lecteurs au droit de réponse, en passant par la causerie, le badinage, la note et la lettre ouverte, variés sont les moyens dont il dispose pour donner, réellement ou fictivement, la parole à ses lecteurs. Plus qu’une figure de récepteur à émouvoir, éduquer ou moraliser, le lecteur devient véritablement une « voix » qui investit les nouveaux espaces d’expression de la civilisation du journal alors en constitution en France. Commenter les faits divers, orienter l’intrigue duroman-feuilleton et réagir à la parution d’une oeuvre deviennent autant d’initiatives accessibles au plus grand nombre. En associant l’étude des imaginaires médiatiques à la poétique du support et à l’histoire culturelle, ces deux journées ont pour objectif d’éclairer les rôles et les statuts du lectorat tels qu’ils sont décelables dans la textualité du journal. Que nous apprend celle-ci sur laparticipation des lecteurs au dialogue créatif avec les producteurs, à la configuration des genres, à la promotion des oeuvres, aux définitions de l’écrivain en régime médiatique ? [less ▲]

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See detailFavorinos d'Arles et ses contemporains : bilinguisme et biculturalisme au IIe siècle apr. J.-C.
Rochette, Bruno ULg

in Marganne, Marie-Hélène; Amato, Eugenio (Eds.) Le traité sur l'exilde Favorinos d'Arles. Papyrologie, Philologie et littérature (2015, April)

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