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See detailFactors controlling spatial patterns and time trends of multiple pesticides in groundwater (Hesbaye chalk aquifer, Belgium)
Hakoun, Vivien ULg; Orban, Philippe ULg; Dassargues, Alain ULg et al

Conference (2016, July 25)

Groundwater contamination by pesticides compounds (parent and degradation by-products) is a well identified environmental issue, however factors influencing their spatial patterns and time trends remain ... [more ▼]

Groundwater contamination by pesticides compounds (parent and degradation by-products) is a well identified environmental issue, however factors influencing their spatial patterns and time trends remain unclear. In this context, 18 years long time series (1996-2013) of 3 banned (atrazine, diuron, simazine), 2 metabolites (deethyaltrazine –DEA, and 2,6-dichlorobenzamide –BAM) and one regulated (bentazone) pesticides compounds are explored, taking into account concentrations below detection limits. Using a bivariate and multivariate (PCA and hierarchical clustering) statistical framework, these time series are related to nitrate (NO3-) and the fraction of young water recharged since 50 years, land use, to aquifer settings (i.e. confining conditions, thickness of the unsaturated zone) and to groundwater table fluctuations. Results show that pesticides compounds are always below detection limits in the confined area where old groundwater lies. However these compounds are detected every year in the unconfined zone with maximal concentrations exceeding the current European water drinking standard of 100 ng.L-1 every year since 2007 for atrazine. We find the greatest significant (p-value < 0.05) positive correlations between the trio atrazine-DEA (tau=0.62), atrazine-NO3- (tau=0.48) and DEA-NO3- (tau=0.49). We identify positive correlations between most compounds, atrazine (tau=0.44), bentazone (tau=0.36), simazine (tau=0.71); DEA (tau=0.58) and BAM (tau=0.44), and water table fluctuations with periods spanning several years. We determine two groups (6 and 9 sites each) of site which relate to the discharge and recharge areas. Sites from the recharge area where higher diuron, simazine and BAM concentrations occurs correlate with a dense localized urban area. Atrazine and bentazone relates to sites with thin unsaturated zones and high mixing in the wells. Our analysis reveals critical factors affecting 7 pesticides compounds. It improves our understanding of the interplay between land use, aquifer settings and transient processes (water fluctuations) on controlling pesticides concentrations in groundwater. [less ▲]

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See detailImpacts of entomopathogenic fungi on biology and behaviour of the invasive Brown Marmorated Stink Bug (Hemiptera, Pentatomidae)
Fingu Mabola, Junior Corneille ULg; Serteyn, Laurent ULg; Bawin, Thomas ULg et al

Poster (2016, July 25)

Halyomorpha halys St˚al (Hemiptera, Pentatomidae) is an invasive stink bug coming from Eastern Asia. Besides causing important yields losses in orchards, crop and vegetable fields, it overwinters inside ... [more ▼]

Halyomorpha halys St˚al (Hemiptera, Pentatomidae) is an invasive stink bug coming from Eastern Asia. Besides causing important yields losses in orchards, crop and vegetable fields, it overwinters inside houses as agglomerates of dozens. In Europe, this Brown Marmorated Stink Bug (BMSB) was accidentally introduced in Switzerland in 2007 and has been later observed in surrounding countries (France, Italy, Germany). Based on the current US situation, we can reasonably fear that BMSB will have colonized most of Europe countries in less than a decade. If we already discern a few fungus strains that are efficient against BMSB, very little is known about their actual impact on the insect itself. So we investigated the in- fluence of a fungal infection on insect development parameters and behaviour. Olfactometry was settled to investigate the dispersion and aggregation trends, while electropenetography was used to assess the feeding behaviour. Our results will be discussed to present changes according to healthy/fungus-infected status, in relation to potential biological control for that pest. [less ▲]

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See detailHydrogeochemical mechanisms driving the occurrence of elevated fluoride contents in crystalline aquifers in Benin, Western Africa
Tossou, Yao ULg; Orban, Philippe ULg; Gesels, Julie ULg et al

Conference (2016, July 24)

Elevated concentrations of fluoride in drinking water is the source of severe healthy problems such as dental or skeletal fluorosis. High concentrations of fluoride are often observed in fractured and ... [more ▼]

Elevated concentrations of fluoride in drinking water is the source of severe healthy problems such as dental or skeletal fluorosis. High concentrations of fluoride are often observed in fractured and altered crystalline aquifers around the world. However, the hydrogeochemical mechanisms leading to such elevated fluoride concentrations are usually not fully understood. In particular, it is important to make the link between these elevated concentrations and the geological context in order to make efficient recommendations on appropriate locations of further groundwater abstraction wells. This is the case in Benin, Western Africa, where groundwater from crystalline bed-rock aquifers is the main source for drinking-water supply. In this context, this research aims to identify the hydrogeochemical processes governing groundwater mineralization and the origin of the high fluoride concentrations. The investigations are based on groundwater samples collected in the central part of the country (Department of Collines), characterized by hard Precambrian aquifers. The hydrogeological system consists of a thin altered bedrock layer (shallow aquifer) and a deeper fractured crystalline bedrock (deep aquifer). The most significant groundwater quality problems in the area relate to the high fluoride (more than 7 mg / l) and nitrate (over 400 mg / l) concentrations in groundwater. The collected hydrogeochemical dataset was explored using geochemical approaches and multivariate statistics. The results reveal that the water mineralization derives from hydrolysis of silicate minerals, but it is also influenced by anthropogenic effects, particularly in the shallow reservoir. However, fluoride has a natural origin, essentially related to weathering of silicate minerals, mainly from biotite. Ion exchanges between groundwater and the rock matrix also contributes to increase fluoride concentrations in groundwater. Earlier saturation of water with calcite and the precipitation of this mineral due to bicarbonate excess reduce calcium activity are favorable of the release of fluoride by rocks. Further investigations are going on to make the link between crystalline rock types, associated primary minerals and fluoride concentrations in order to identify the geological contexts which are more prone to such problems. [less ▲]

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See detailSelf-inhibition of synthesis reduces antigen presentation of the alcelaphine herpesvirus 1-encoded latency-associated protein, aLANA
Sorel, Océane; Myster, Françoise; Vanderplasschen, Alain et al

Conference (2016, July 23)

Alcelalphine herpesvirus 1 (AlHV-1) persistently infects its natural host, the wildebeest, without inducing any clinical signs. However, cross-transmission to other ruminant species leads to the ... [more ▼]

Alcelalphine herpesvirus 1 (AlHV-1) persistently infects its natural host, the wildebeest, without inducing any clinical signs. However, cross-transmission to other ruminant species leads to the development of a deadly lymphoproliferative disease named malignant catarrhal fever (MCF). AlHV-1 ORF73 encodes the latency-associated nuclear antigen (LANA)-homolog protein termed aLANA. Similarly to other viral genome maintenance proteins encoded by gammaherpesviruses, aLANA has recently been shown to be essential for viral persistence and induction of MCF. Here we have investigated the self-inhibition of antigen presentation by aLANA and the potential role of such mechanism during the development of MCF. We showed that the GE-rich repeat domain of aLANA was sufficient to inhibit the presentation of an epitope linked to it. Though antigen presentation in absence of GE was dependent upon proteasomal degradation of aLANA, a lack of GE did not affect protein turnover. We further found that similarly to EBNA-1 GAr, aLANA GE downregulated protein self-synthesis. Likewise, such mechanism could be associated with reduced antigen presentation in vitro. In addition, in-frame insertion of GE repeat domain in a heterologous eGFP protein significantly down-regulated protein steady-state levels and self-antigen presentation. Next, we modified the AlHV-1 ORF73 gene sequence to reduce the purine bias in GE, without affecting the peptidic sequence. Such codon-modified aLANA GEm construct displayed increased antigen presentation. Finally, we generated an AlHV-1 recombinant strain expressing a GE-deficient aLANA protein and observed that viral growth was not affected in vitro by the absence of aLANA GE domain and MCF could be induced in rabbits irrespective of the expression of full-length aLANA or GE-deficient aLANA protein. [less ▲]

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See detailLa succession du prince-évêque de Liège dans les biens des ecclésiastiques
Lagasse, Benoît ULg

Conference (2016, July 23)

Explication du régime spécifique au diocèse de Liège de la succession du prince-évêque dans les biens des ecclésiastiques (distinction meubles/immeubles versus distinction biens propres/biens de l'Eglise ... [more ▼]

Explication du régime spécifique au diocèse de Liège de la succession du prince-évêque dans les biens des ecclésiastiques (distinction meubles/immeubles versus distinction biens propres/biens de l'Eglise en droit canonique général). [less ▲]

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See detailLe surréalisme curacien : une construction néerlandaise ?
Andringa, Kim ULg

Conference (2016, July 22)

Depuis les années 1930, une riche littérature « locale » s’est développée sur l’île de Curaçao, qui fait alors partie des Antilles néerlandaises. Presque d’emblée, plusieurs de ses auteurs, poètes comme ... [more ▼]

Depuis les années 1930, une riche littérature « locale » s’est développée sur l’île de Curaçao, qui fait alors partie des Antilles néerlandaises. Presque d’emblée, plusieurs de ses auteurs, poètes comme romanciers, se voient attribuer l’étiquette « surréaliste » par la critique littéraire néerlandaise, et ce malgré l’absence de liens ou de contacts avec des groupes surréalistes d’autres pays. Encore en 2012, quatre poètes caribéens, dont trois curaciens, figurent dans la Nieuwe anthologie van de Nederlandse surrealistische poëzie. Nous tâcherons d’analyser les motifs et les critères sous-jacents à cette catégorisation, depuis quelque temps souvent récusée, afin d’établir s’il y a une réelle sensibilité surréaliste dans cette littérature antillaise néerlandophone, ou s’il s’agit d’une tentative d’apprivoisement de la métropole face à l’émergence de cette nouvelle littérature néerlandaise transatlantique, issue d’une culture différente et qui contribue à une décolonisation des esprits. [less ▲]

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See detailThe verbal overshadowing effect in children and adults is unrelated to the specific content of descriptions
Vanootighem, Valentine ULg; Brédart, Serge ULg; Dehon, Hedwige ULg

Poster (2016, July 21)

Verbal descriptions of unfamiliar faces have been found to impair later identification of these faces in children and adults, a phenomenon known as the “verbal overshadowing effect” (VOE, Schooler and ... [more ▼]

Verbal descriptions of unfamiliar faces have been found to impair later identification of these faces in children and adults, a phenomenon known as the “verbal overshadowing effect” (VOE, Schooler and Engstler-Schooler, 1990). The present study thoroughly examined the person descriptive abilities of 7–8, 10–11, and 13–14-year-old children and adults and their influence on later identification performance. Our aim was to specifically assess the prediction of the “content” account suggesting that a verbal overshadowing arises because participants generate an inadequate verbal description and later rely upon it during retrieval. Results showed a verbal overshadowing effect in all age groups but neither accuracy, length nor content of descriptions were found to be associated with identification accuracy. [less ▲]

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See detailThe influence of COMT on the neural substrates of short-term memory in normal aging
Collette, Fabienne ULg; Manard, Marine ULg; Salmon, Eric ULg

Conference (2016, July 21)

Working memory dopaminergic modulation is generally expressed in healthy aging by an advantage for carriers of the Met allele at behavioral and brain activity levels. However, most tasks used did not ... [more ▼]

Working memory dopaminergic modulation is generally expressed in healthy aging by an advantage for carriers of the Met allele at behavioral and brain activity levels. However, most tasks used did not allow to easily disentangle the contribution of maintenance and manipulation processes. We explored the effect of COMT genotype on the maintenance process using a Sternberg memory task varying the amount of information presented, in young and older homozygous carriers for the Val and Met alleles of the COMT gene. Although no clear behavioral difference was observed between groups, patterns of cerebral activity indicate difficulties for Met older individuals to maintain stable representations. These results will be discussed in terms of dopaminergic contribution to stability/flexibility of cognitive processes during aging. [less ▲]

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See detailBridging familiarity and novelty detection: a matter of timing?
Delhaye, Emma ULg; Barbeau, Emmanuel; Moulin, Christopher et al

Conference (2016, July 21)

Detailed reference viewed: 5 (2 ULg)
See detailSelf-assembly of capillary multipoles
Poty, Martin ULg; Lagubeau, Guillaume; Lumay, Geoffroy ULg et al

Conference (2016, July 21)

Self-assembly of floating particles driven by capillary forces at some liquid-air interface leads to the formation of two-dimensionnal structures. Using a 3d printer, millimeter scale objets are produced ... [more ▼]

Self-assembly of floating particles driven by capillary forces at some liquid-air interface leads to the formation of two-dimensionnal structures. Using a 3d printer, millimeter scale objets are produced. Their 3d shape is chosen in order to create capillary multipoles. The capillary interactions between these components can be either attractive or repulsive depending on the interface local deformations along the liquid-air interface. In order to understand how the shape of an object deforms the interface, we developed an original profilometry method. The measurements show that specific structures can be programmed by selecting the 3d branched shapes. [less ▲]

Detailed reference viewed: 16 (2 ULg)
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See detailSoil fiction: the experience of a neglected urban thing
Meulemans, Germain ULg

Conference (2016, July 21)

This paper starts with the story of the Soil Fiction project – a residence in which artists, anthropologists and a soil-scientist worked together on developing an exhibition on urban soils – in order to ... [more ▼]

This paper starts with the story of the Soil Fiction project – a residence in which artists, anthropologists and a soil-scientist worked together on developing an exhibition on urban soils – in order to address what speculative realism might bring to anthropological modes of inquiry. For more than 150 years, urban soils were left unnoticed by modern science because of their messiness and boundedness with human activities. Yet, they are a prevalent aspect of urban conditions of life. Through six months of collective work, Soil Fiction explored some of the neglected paths that attach us to urban soils. Departing from attempts to adapt modern-day science to urban soils, it imagined the practices of a minor science developed through a journey along them. These practices were given consistence through the creation of installations and films. Drawing on Stengers’s approach to speculative thinking, I discuss the importance of inventing propositions that work as ‘lures for feelings’. In this, rather than being a figment of the imagination, the craft of speculative imagining can attract experience. Fiction and exhibition making become ways to inquire into the world, to intensify hypothesis, and to forge other relationships with the world. I conclude that imaginative experiments such as Soil Fiction are not only knowledge practices in themselves, but also add more reality to the world. Responding to Ingold’s call for an anthropology that re-unites imagination and reality together, they conjure up research modes that do not discriminate between soils and our knowledge of them. [less ▲]

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See detailIntegrating biological indicators in a monitoring network to improve soil quality diagnosis – a case study in Southern Belgium
Krüger, Inken ULg; Chartin, Caroline; van Wesemael, Bas et al

Conference (2016, July 21)

Detailed reference viewed: 30 (4 ULg)
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See detailenseigner massivement la littérature jeunesse : la Formation en Ligne Ouverte à tous de l'Université de Liège
Centi, Valérie; D'Anna, Vincianne; Delbrassine, Daniel ULg et al

Conference (2016, July 20)

Detailed reference viewed: 31 (1 ULg)
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See detailLa logique de l'espace dans les stemmas de Lucien Tesnière
Mazziotta, Nicolas ULg

Conference (2016, July 19)

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See detailLes représentations du français dans le sous-système éducatif anglophone du Cameroun: le regard des élèves de la filière Arts
Mouto Betoko, Christiane ULg

Conference (2016, July 19)

Avec l’entrée du Cameroun au Commonwealth of Nations d’une part, et, le rayonnement de la langue anglaise d’autre part, les Francophones, majoritaires au Cameroun, se ruent à l’apprentissage de l’anglais ... [more ▼]

Avec l’entrée du Cameroun au Commonwealth of Nations d’une part, et, le rayonnement de la langue anglaise d’autre part, les Francophones, majoritaires au Cameroun, se ruent à l’apprentissage de l’anglais. Cependant, le mouvement inverse n’est pas visible dans la communauté anglophone minoritaire. Toutefois, un nombre non négligeable d’élèves anglophones s’engagent à poursuivre l’apprentissage du français jusqu’à la fin de leur cursus secondaire. Pour comprendre les raisons de cet engagement, nous allons répondre aux questions telles que : quelle est l’image que ces élèves se font de la langue française ? À quels projets l’associent-ils? Quel est impact des médias dans leur rapport avec le français ? Quelle est la perception de la plus-value de l’apprentissage de cette langue ? Quel est l’intérêt de la prise en compte des représentations de ces élèves dans l’enseignement du French au Cameroun ? [less ▲]

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See detailNeural correlates of memory for internal thoughts versus external stimuli experienced in natural settings
Stawarczyk, David ULg; Jeunehomme, Olivier ULg; D'Argembeau, Arnaud ULg

Poster (2016, July 19)

To investigate the brain regions supporting the remembrance of internal thoughts versus external events, we asked participants to perform a short walk while wearing a lifelogging device that continuously ... [more ▼]

To investigate the brain regions supporting the remembrance of internal thoughts versus external events, we asked participants to perform a short walk while wearing a lifelogging device that continuously and automatically took pictures. In a subsequent fMRI session, they were shown brief sequences of pictures from their walk and were asked to remember either external events or internal thoughts that they experienced while walking. Results showed that remembering internal thoughts activated the medial prefrontal cortex and temporal poles to a greater extent than remembering external events, whereas remembering external events was associated with higher activation in lateral frontoparietal regions. These findings suggest that memory for internal thoughts involves the reactivation of brain regions supporting the initial formation of these thoughts. [less ▲]

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See detailAlumina and zircon refractory ceramic molds fabrication by additive methods for metal alloys casting
Bister, Geoffroy; Hautcoeur, Dominique; Deschuyteneer, Dorian et al

Conference (2016, July 19)

Traditional processes for the foundry molds fabrication need numerous and rather time consuming steps. These processes are not really adapted to small series or prototypes. The research project exposed in ... [more ▼]

Traditional processes for the foundry molds fabrication need numerous and rather time consuming steps. These processes are not really adapted to small series or prototypes. The research project exposed in this contribution proposes an alternative method combining the advantages of molding (free formulation of metal alloys, economy on material and on time of machining) with those of the additive processes (short steps between 3D-model and final product, very complex geometries available). For short series the selective laser melting process (SLM) allows the building of molds in a very short time compared to the traditional investment casting method. This technique also permits the unique advantage to control the design of the shell thickness and structure in order to have a better control of the thermal fluxes during metal cooling. This would potentially ensure a better control of the casting defaults. In this presentation, molds built with alumina and zircon as raw materials will be presented. Two metallic alloys have been tested in order to validate alumina and zircon as mold materials; the first, AlCu4MgSi chosen as low melting point alloy reference and the second, stainless steel 316L, as high melting point alloy reference [less ▲]

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See detailVariations lexicales dans la mise en prose de Barlaam et Josaphat
Lambert, Adélaïde ULg

Conference (2016, July 19)

La confrontation de la version anonyme en vers de Barlaam et Josaphat avec sa mise en prose, produite au XIIIe siècle, offre un point de vue privilégié sur la langue littéraire en prose, à l’aube de son ... [more ▼]

La confrontation de la version anonyme en vers de Barlaam et Josaphat avec sa mise en prose, produite au XIIIe siècle, offre un point de vue privilégié sur la langue littéraire en prose, à l’aube de son épanouissement. Parallèlement au retranchement d’épisodes entiers, le remanieur s’applique à conserver une étroite proximité avec la lettre de son modèle francien, et semble tendre vers un compromis entre fidélité au texte-source et intelligibilité du texte-cible. Ainsi, à côté de l’importation massive du matériau lexical et des structures syntaxiques du texte versifié, toutes ses interventions sont observables. Notre communication s’est focalisée sur un échantillon de neuf substitutions lexicales dont nous avons mesuré la fréquence et dont il s’agissait d’identifier les implications. En tant que témoins de l’actualisation linguistique du texte-source, ces variations (diachroniques et/ou diaphasiques) permettent d’améliorer la connaissance du vocabulaire de la mise en prose de Barlaam et Josaphat et de cerner avec plus de précision la sensibilité du remanieur à l’égard du lexique de sa source. [less ▲]

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See detailStudy of Sn and Fe based electrode materials for Alkali-ion batteries by in situ Mössbauer spectroscopy
Mahmoud, Abdelfattah ULg; Sougrati, Moulay Tahar; Hermann, Raphaël ULg et al

Conference (2016, July 19)

Li-ion batteries are widely used for electrochemical energy storage, because of their high energy density and efficiency. The most significant challenges in the development of advanced Li-ion batteries ... [more ▼]

Li-ion batteries are widely used for electrochemical energy storage, because of their high energy density and efficiency. The most significant challenges in the development of advanced Li-ion batteries concern the electrode materials. Indeed, the electrodes properties critically determine the capacity, performance, and durability of alkali-ion batteries. In the past five decades, Mössbauer spectroscopy has been an important analytical technique for investigating the structural, magnetic and electronic properties of energy materials. Mössbauer spectroscopy allows simultaneous investigation of bulk and surface characteristics. It is a non-destructive technique that can follow the behavior of electrode materials during the reaction process in situ and operando [1]. Its high resolution enables the observation of all Mössbauer active phases and the measure of their relative quantities . Iron and tin containing materials are of considerable interest as electrode material for Li-ion batteries [2, 3]. In this presentation, we report in situ and operando measurements of new electrode materials based on Fe and Sn during electrochemical cycling by combining Mössbauer spectroscopy with complementary techniques (X-ray diffraction, magnetic measurements, impedance spectroscopy, etc.) to study and investigate the electrochemical behavior of the electrode materials. [less ▲]

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See detailMetagenetics and predictive microbiology: a new tool to understand the kinetics of microbial subpopulation in minced pork meat
Cauchie, Emilie ULg; Delhalle, Laurent; Taminiau, Bernard et al

Poster (2016, July 18)

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See detailMetagenetics and predictive microbiology: a new tool to understand the kinetics of microbial subpopulations in Belgian white pudding
Cauchie, Emilie ULg; Gand, Mathieu; Kergourlay, Gilles et al

Poster (2016, July 18)

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See detailRecollection versus familiarity in normal aging and in mild cognitive impairment: Impact of test format.
Simon, Jessica ULg; Gilsoul, Jessica ULg; SALMON, Eric ULg et al

Poster (2016, July 18)

The aim of this study was to investigate the impact of test format on recollection and familiarity in normal aging and in MCI. Seventy young participants, 65 younger-old, 53 older-old, and 13 MCIs were ... [more ▼]

The aim of this study was to investigate the impact of test format on recollection and familiarity in normal aging and in MCI. Seventy young participants, 65 younger-old, 53 older-old, and 13 MCIs were presented with forced-choice and yes/no visual recognition memory tasks with the Remember/Know/Guess paradigm. The young people had better recognition performance than younger-old, who performed better than older-old and MCIs. Recollection and familiarity declined progressively in healthy aging. In MCI, recollection was more affected than familiarity, but patients demonstrated a more liberal use of familiarity. Finally, test format did not influence strongly the results. Young people used recollection more often in the forced-choice task compared to the yes/no task. [less ▲]

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See detailStatistical physics of memory driven systems
Hubert, Maxime ULg

Poster (2016, July 18)

For classical systems, statistical description is usually required when the dimension of the system phase space is important. This description is used when considering many body problems such as the ... [more ▼]

For classical systems, statistical description is usually required when the dimension of the system phase space is important. This description is used when considering many body problems such as the thermodynamical description of fluids, granular media or the diffusion of Brownian particles in the presence of a thermal reservoir. Can this limit be reached at the single particle level? We address this question by considering a single particle coupled to its own past, via a wave-mediated size-controllable memory, which stores the past trajectory of the particle. Such an object has been turn into reality by Couder et al [1,2] by using liquid bouncing droplets that interact with the waves they generate by impacting a liquid surface. In those experiments, the memory is made by stationary waves with a tunable damping time. The wave memory triggers various regime from individual self-propelled particle motion to structured chaos [3] or self-organization processes between a particle and its waves [4]. In the limit of a large amount of “souvenirs” stored in the wave field, we will show that the dynamics can be well described by the tools of non-equilibrium statistical mechanics. Both the dynamics of the particle and the wave-mediated memory are investigated. We show that, from the particle-point of view, the memory acts as a random force. The particle dynamics is adequately described by a Langevin equation for self-propelled systems. The corresponding Fokker-Planck equation shows that the memory can be seen as a thermal reservoir whose temperature is tuned via the amount of “souvenirs” in the dynamics. The features of this unusual wave-like thermal reservoir are investigated from an energetic and entropic perspective. We show that the global wave field is on average weaker that one would expect from superposition of random wave fields. This depletion originates from destructive interferences that the particle generates along its trajectory, corresponding to a kind-of minimization principle. [1] Y. Couder, S. Protière, E. Fort & A. Boudaoud, “Walking and orbiting droplets”, Nature, 437, 208 (2005). [2] A. Eddi, E. Sultan, J. Moukhtar, E. Fort, M. Rossi & Y. Couder, “Information stored in Faraday waves: the origin of a path memory”, J. Fluid Mech., 674, 433- 463 (2011). [3] S. Perrard, M. Labousse, E. Fort & Y. Couder, “Chaos driven by interfering memory”, Phys. Rev. Lett, 113, 104101 (2014). [4] S. Perrard, M. Labousse, M. Miskin, E. Fort & Y. Couder, “Self-organization into quantized eigenstates of a classical wave-driven particle”, Nat. Comm., 5, 3219 (2014). [less ▲]

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See detailOn the organization of episodic future thoughts in event clusters
D'Argembeau, Arnaud ULg

Conference (2016, July 18)

Memory can be flexibly used to image events that might happen in one’s personal future, a capacity that has been referred to as episodic future thinking. In this talk, I will present data showing that ... [more ▼]

Memory can be flexibly used to image events that might happen in one’s personal future, a capacity that has been referred to as episodic future thinking. In this talk, I will present data showing that many episodic future thoughts are not represented in isolation, but instead are part of higher-order event clusters that organize imagined events in coherent themes and causal sequences. Personal goals seem to play an important role in this organization and neuroimaging evidence shows that event clusters recruit brain regions supporting conceptual and integrative processing. These findings suggest that episodic future thinking involves the integration of specific event representations with autobiographical knowledge, which contextualizes imagined events with respect to personal goals and general expectations about one’s life. [less ▲]

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See detailProbing single molecules with the AFM: Force, motion, dynamics, and function
Duwez, Anne-Sophie ULg

Conference (2016, July 18)

Detailed reference viewed: 8 (2 ULg)
See detailUltrafast Spin Dynamics in FeRh
Ostler, Thomas ULg

Conference (2016, July 16)

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See detailLe français pour l’unité et l’intégration nationales au cameroun
Mouto Betoko, Christiane ULg

Conference (2016, July 16)

La politique du bilinguisme officiel s’est imposée au Cameroun pour des raisons d’unité nationale suite à une double colonisation franco-britannique. En milieu scolaire, le bilinguisme renvoie ... [more ▼]

La politique du bilinguisme officiel s’est imposée au Cameroun pour des raisons d’unité nationale suite à une double colonisation franco-britannique. En milieu scolaire, le bilinguisme renvoie généralement à l’enseignement du français en tant que deuxième langue officielle aux Anglophones et, à l’enseignement de l’anglais en tant que deuxième langue officielle aux Francophones. Néanmoins, les élèves anglophones éprouvent d’énormes difficultés d’intégration à la fin des études secondaires. Quels sont donc les objectifs de l’enseignement du français aux élèves anglophones ? Quelle est l’approche méthodologique mise en œuvre pour atteindre ces objectifs ? Et enfin, comment allier objectifs scolaires du bilinguisme et méthodologie du FLE pour préparer les élèves anglophones à la vie après le secondaire ? [less ▲]

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See detailExamine the effects of two adjustments to the lz statistic
Riley, Barth; Magis, David ULg

Conference (2016, July 14)

Conformity to a known distribution and sensitivity to response aberrance are desirable properties of person-fit statistics. This simulation study examined the joint and independent effects of two ... [more ▼]

Conformity to a known distribution and sensitivity to response aberrance are desirable properties of person-fit statistics. This simulation study examined the joint and independent effects of two adjustments to the standardized log-likelihood statistic (lz): (1) correction of the negatively skewed distribution of lz (Snijders, 2001), and (2) improving the sensitivity of the statistic by employing more accurate estimates of item response probability using symmetric functions (Dimitrov and Smith, 2006). Data were simulated using three test lengths (10, 20, 30 items). Data containing misfitting response patterns were simulated using three aberrant response patterns (cheating, guessing, and inattentiveness), and three levels of aberrance (i.e., proportion of item responses affected by misfit; 10%, 30% and 50%). Data containing no simulated misfitting response patterns were also generated for each test length. Non-misfitting responses were generated using the dichotomous Rasch measurement model. For each combination of independent variables, a dataset was generated consisting of 5,000 simulees. Four fit statistics were compared: lz, lz* (Snijders adjustment), lzSYM (Dimitrov and Smith adjustment), and lzSYM* (both adjustments). Mean Type I error rates were ≤ 0.1 across all conditions. The lz* statistic produced the best control of Type I error, which was often below the nominal Type I error rate, whereas the empirical Type I error rate for the unadjusted lz statistic most closely approximated the nominal rate. In contrast, lzSYM and lzSYM* yielded empirical Type I error rates larger than the nominal rate, with the discrepancy being particularly pronounced as the length of the test decreased. As might be expected, power to detect misfitting response patterns increased with test length and with the percentage of misfitting response patterns in the sample. Both lzSYM and lzSYM* evidenced improved power in detecting misfitting response patterns compared to lz and lz*, particularly for guessing response patterns and/or on shorter (i.e., 10 item) tests. [less ▲]

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See detailRoland Barthes et les écritures de la chronique
Stienon, Valérie ULg

Conference (2016, July 14)

La plupart des textes de Roland Barthes sont le produit d’une commande – qu’elle soit amicale, événementielle, éditoriale. L’inscription dans un genre ou l’investissement d’un mode d’écriture s’appuie ... [more ▼]

La plupart des textes de Roland Barthes sont le produit d’une commande – qu’elle soit amicale, événementielle, éditoriale. L’inscription dans un genre ou l’investissement d’un mode d’écriture s’appuie donc sur une situation de communication dont les paramètres sont souvent bien déterminés et qui est elle-même guidée par une demande préalable, de sorte que dispositif générique et horizon d’attente s’entre-déterminent de manière cruciale. Plus encore, les commandes passées à Barthes, avant d’être des livres, prennent généralement la forme d’articles dans des périodiques. Il y a de la sorte une dimension intrinsèquement circonstancielle à l’écriture barthésienne, dimension propice à la relation d’actualité. Dès lors, dans quelle mesure la chronique peut-elle offrir une clé de lecture du cheminement d’écriture de Barthes et du parcours de sa pensée ? [less ▲]

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See detailCharacterization of FRD3, a zinc and iron homeostasis actor in Arabidopsis relatives
Scheepers, Maxime ULg; Charlier, Jean Benoit; Spielmann, Julien ULg et al

Conference (2016, July 14)

Zinc and iron are two essential micronutrients for plants. The homeostasis networks of the two metals are intertwined. Arabidopsis halleri is a zinc- and cadmium-tolerant and zinc-hyperaccumulating ... [more ▼]

Zinc and iron are two essential micronutrients for plants. The homeostasis networks of the two metals are intertwined. Arabidopsis halleri is a zinc- and cadmium-tolerant and zinc-hyperaccumulating species, which also present adaptation of its iron homeostasis(1,4). Transcriptomic studies identified genes which are constitu-tively over-expressed in Arabidopsis halleri compared to Arabidopsis thaliana and which may have a role in metal tolerance or accumulation(2-4). Among them, a candidate gene encodes the FRD3 (FERRIC REDUCTASE DEFECTIVE 3) protein, a member of the MATE family of membrane transporters. FRD3 is a citrate transporter involved in iron homeostasis(5-7) and plays a role in zinc tolerance in A. thaliana(8). The FRD3 gene displays a complex regulation. In A. thaliana, alternative transcript initiation for FRD3 determines two transcripts, which dif-fer in their 5'UTRs and have differential translation efficiency. The two transcripts are selectively regulated under stress conditions: iron and zinc depletion, zinc excess or cadmium presence(9). In A. halleri, a single highly ex-pressed FRD3 transcript with high translation efficiency is present(9). We are further examining the FRD3 function in zinc and iron homeostasis in A. thaliana and A. halleri. We will present data (i) on the high expression of FRD3 in A. halleri, (ii) on the functional characterization of the two alternative FRD3 transcripts and their role in metal homeostasis in A. thaliana in comparison with the A. halleri FRD3 transcript and (iii) on the zinc phenotypes of the frd3 A. thaliana mutant. [less ▲]

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See detailOpen source programming: a new hope for psychometric research
Magis, David ULg

Conference (2016, July 14)

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

Current psychometric research is most often supported by computer software. New research perspectives often imply intensive simulation studies to validate the tested theories or hypotheses, and therefore require accurate, fast and stable implementation. To this regards, open source programming (such as in the R language) is a promising approach allowing for flexible implementation, data generation, replication of studies, and worldwide dissemination. The purpose of this talk is to illustrate how psychometrics and open source programming (with special emphasis on the R language) can interact and contribute to each other, by means of some selected examples. Several topics will be illustrated, among others: why open source programming is (to my opinion) as important as psychometric research; why we need for stable and complete implementation of psychometric and statistical routines for research purposes (for e.g., CAT); how accurate implementation of IRT routines can lead to unexpected theoretical results; why (and how) open source software can be valued as research output. Most examples will arise from the CAT framework and the R package catR for simulating CAT patterns. [less ▲]

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See detailOn the use of ROC curves in DIF simulation studies
Magis, David ULg; Tuerlinckx, Francis

Conference (2016, July 14)

Simulation studies are often used to compare methods to detect differential item functioning (DIF). However, comparing the performance of such methods can become complicated when the identification of DIF ... [more ▼]

Simulation studies are often used to compare methods to detect differential item functioning (DIF). However, comparing the performance of such methods can become complicated when the identification of DIF items relies on statistics based on pre-defined significance level or on pre-established cutoff values. DIF methods based on conceptually different approaches may therefore become incomparable in terms of summary DIF statistics such as false alarm rate or hit rate. The purpose of this talk is to overcome this analytic issue by introducing receiver operating characteristic (ROC) curves in this context. ROC curves allow for global comparison of methods’ performances by computing pairs of (false alarm, hit) rates and representing them on a common scatter plot. Several summary ROC statistics can be considered for further analysis. The application of the ROC curve methodology, together with its limitation and possible extensions, is illustrated by a simple simulation study that compares three score-based DIF methods (Mantel-Haenszel, standardization and Delta plot). [less ▲]

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See detailOperational costs and externalities in optimal intermodal network design
Mostert, Martine ULg; Limbourg, Sabine ULg; Caris, An

Conference (2016, July 13)

Transportation of goods is essential for the economy but also leads to harmful impacts related to human health aspects. Intermodal transport is promoted by Europe to reduce these negative externalities ... [more ▼]

Transportation of goods is essential for the economy but also leads to harmful impacts related to human health aspects. Intermodal transport is promoted by Europe to reduce these negative externalities. The objective of this paper is to analyze at the strategic level how the flow repartition varies between three modes (road, intermodal rail and intermodal inland waterway) according to different implemented policies. A mathematical allocation model is developed and tested on the Belgian case study, in order to determine the observed changes between the single minimization of (operational or health-related external) costs and the introduction of additional road taxes. [less ▲]

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See detailSanté et sécurité au travail: un modèle intégratif pour prédire les comportements de sécurité.
Laurent, Julie ULg; Chmiel, Nik; Hansez, Isabelle ULg

Conference (2016, July 13)

INTRODUCTION. La santé et la sécurité sont deux thématiques qui ont souvent été traitées séparément dans la littérature scientifique. Hansez et Chmiel (2010) ont démontré la pertinence d’utiliser le ... [more ▼]

INTRODUCTION. La santé et la sécurité sont deux thématiques qui ont souvent été traitées séparément dans la littérature scientifique. Hansez et Chmiel (2010) ont démontré la pertinence d’utiliser le modèle ‘demandes-ressources’ (Bakker et Demerouti, 2007) afin d’expliquer les comportements de sécurité au travail. La présente étude propose d’étendre ce modèle en y incluant un processus d’échange social, spécifiquement lié à la sécurité, en plus des processus motivationnel, cognitif-énergétique et instrumental. METHODES. Notre échantillon est composé de 1922 travailleurs d’une entreprise métallurgique belge. Notre modèle théorique a été testé à l’aide de la modélisation par équations structurales, avec le logiciel MPlus. RESULTATS. Le modèle final présente des indices d’adéquation acceptables (²=3346.63, dl=678, RMSEA=.04, CFI=.92, NNFI=.91). Les résultats montrent que les quatre processus psychologiques sont impliqués. Les violations « situationnelles » (i.e. le fait de commettre des infractions qui sont dues à des lacunes de l’organisation et sans lesquelles le travail ne pourrait pas être réalisé) sont expliquées par (1) un processus motivationnel, puisque les ressources encouragent les travailleurs à être stimulés par leur travail, et ainsi à moins commettre ce type d’infractions (2) un processus instrumental, puisque percevoir l’implication de son management dans la sécurité est associé directement à moins de violations situationnelles, et par (3) un processus social, puisque les ressources de travail permettent aux employés de percevoir l’implication de leur management dans la sécurité, et de répondre à cet intérêt en considérant la sécurité comme faisant partie de leur rôle, ce qui les encourage ensuite à participer à des activités volontaires liées à la sécurité. D’autre part, les violations de « routine » (i.e. le fait de « prendre des raccourcis » et de ce fait ne pas respecter les procédures de sécurité) sont expliquées par les mêmes processus d’échange social et motivationnel, mais aussi par un processus cognitif-énergétique, puisque des conditions de travail contraignantes peuvent mener à plus de stress, associé à son tour à plus de violations de routine. DISCUSSION. La principale limitation de cette étude est la nature auto-rapportée des données, pouvant mener à différents biais. Néanmoins, différentes implications pratiques peuvent être mises en évidence. Les entreprises désireuses de réduire les violations des règles de sécurité devraient considérer à la fois les processus spécifiquement liés à la sécurité et des processus psychologiques plus larges. Par exemple, outre l’importance d’améliorer les conditions de travail considérées comme des ressources, il est important de garder à l’esprit que ces ressources déterminent des processus complexes d’échanges sociaux spécifiquement liés à la sécurité, à travers l’influence primordiale du management. [less ▲]

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See detailShaping (im)mobility in border camps: a case study of the transformation of Calais camps and its actors
Da Silva, Amanda Carolina ULg

Conference (2016, July 13)

This paper explores the transition of informal temporary camps on the French border to a sustainable state, and discusses how local policy decisions and non-state actors worked together for the ... [more ▼]

This paper explores the transition of informal temporary camps on the French border to a sustainable state, and discusses how local policy decisions and non-state actors worked together for the implementation of a semi-permanent exclusion system based on the refugee crisis. I observe this issue as a result of a securitization process. The securitization apparatus (speech acts and policies), produced the immobility of a group. In the other hand actors will emerge to produce mobility. When a situation is defined as a crisis, atypical actions can be employed to protect the «political community». I started from the assumption that dialectic relation between securitization and camps actors had a high impact on the projects of refugees, and so long in their mobility. This is a question of integration policies at the local level. I aim to highlight the local level relevance, where the integration is primarily implemented, and therefore local and regional context should matter as much as the national model for integration (Martiniello, 2013). In Calais, due to the lack of immigrants policies, civilians associations started to react and build informal camps, but due to recent "crisis" the Stat concentrated all refugees in a single camp, 6 kilometers from the city center, called bidonville. [less ▲]

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See detailA Crypt of Swipes. Charles Burns Haunted by Tintin
Crucifix, Benoît ULg

Conference (2016, July 13)

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See detailGamma-Ray Spectrometry: Experimental Measurement and Monte Carlo Simulation using GEANT4 toolkit
Guembou Shouop, Cébastien Joel ULg; Ndontchueng Moyo, Maurice; Chene, Grégoire ULg et al

Poster (2016, July 13)

Nowadays the precision in the measurement has become a challenge for physicists. That is why in recent decades, the interest is very granted to simulation. Since 1940, the method Monte Carlo is more ... [more ▼]

Nowadays the precision in the measurement has become a challenge for physicists. That is why in recent decades, the interest is very granted to simulation. Since 1940, the method Monte Carlo is more useful for validation and even for prediction of the results of the experiment. The aim of this study is to validate experimental models. Our laboratories are equipped with HPGe gamma spectrometers for measuring the natural radioactivity, it becomes interesting to compare and even to improve the performance of our system. Geant4 is used for the construction of the geometry of detection, the physics processes and the primary particles. First and prliminary result was prsented in this paper. [less ▲]

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See detailThe Methods of Managgement: An Answer to the crisis
Robert, Jocelyne ULg

Conference (2016, July 12)

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See detailFailure multiscale simulations of composite laminates based on a non-local mean-field damage-enhanced homogenization
Wu, Ling ULg; Adam, Laurent; Doghri, Issam et al

Conference (2016, July 12)

A multiscale method is developed to study the failure of carbon fiber reinforced composites. In order to capture the intra-laminar failure, a non-local mean-field homogenization (MFH) method accounting ... [more ▼]

A multiscale method is developed to study the failure of carbon fiber reinforced composites. In order to capture the intra-laminar failure, a non-local mean-field homogenization (MFH) method accounting for the damage evolution of the matrix phase of the composite material [1] is considered. In that formulation, an incremental-secant MFH approach is used to account for the elastic unloading of the fibers during the strain softening of the matrix. In order to avoid the strain/damage localization caused by the matrix material softening, an implicit non-local method [2] was reformulated to account for the composite material anisotropy. As a result, accurate predictions of the composite softening behavior and of the different phases response is possible, even for volume ratios of inclusions around 60%. In particular it is shown that the damage propagation direction in each ply follows the fiber orientation in agreement with experimental data. The delamination process is modeled by recourse to a hybrid discontinuous Galerkin (DG)/ extrinsic cohesive law approach. As for the extrinsic cohesive law (ECL), which represents the fracturing response only, and for which cohesive elements are inserted at failure onset, the method does not suffer from a mesh-dependent effect. However, because of the underlying discontinuous Galerkin method, interface elements are present since the very beginning of the simulation avoiding the need to propagate topological changes in the mesh with the propagation of the delamination. Moreover, the pre-failure response is accurately captured by the material law though the DG implementation, by contrast to usual intrinsic cohesive laws. As a demonstration of the efficiency and accuracy of the method, a composite laminate with a quasi-isotropic sequence ([90/45/-45/90/0]S) and an open-hole geometry is studied using the multiscale method [3] and the results are compared to experimental data. The numerical model is found to predict the damage bands along the fiber directions as observed in the experimental samples inspected by X-ray computed tomography (XCT). Moreover, the predicted delamination pattern is found to match the experimental observations. REFERENCES [1] L. Wu, L. Noels, L. Adam, I. Doghri, An implicit-gradient-enhanced incremental-secant mean- field homogenization scheme for elasto-plastic composites with damage, International Journal of Solids and Structures, 50, 3843-3860, 2013. [2] R. Peerlings, R. de Borst, W. Brekelmans, S. Ayyapureddi, Gradient-enhanced damage for quasi-brittle materials. International Journal for Numerical Methods in Engineering, 39, 3391-3403, 1996. [3] L. Wu, F. Sket, J.M. Molina-Aldareguia, A. Makradi, L. Adam, I. Doghri, L. Noels, A study of composite laminates failure using an anisotropic gradient-enhanced damage mean-field homogenization model, Composite Structures, 126, 246–264, 2015. [less ▲]

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See detailMean-Field-Homogenization-based stochastic multiscale methods for composite materials
Wu, Ling ULg; Lucas, Vincent ULg; Adam, Laurent et al

Conference (2016, July 12)

When considering a homogenization-based multiscale approach, at each integration-point of the macro-structure, the material properties are obtained from the resolution of a micro-scale boundary value ... [more ▼]

When considering a homogenization-based multiscale approach, at each integration-point of the macro-structure, the material properties are obtained from the resolution of a micro-scale boundary value problem. At the micro-level, the macro-point is viewed as the center of a Representative Volume Element (RVE). However, to be representative, the micro-volume-element should have a size much bigger than the micro-structure size. For composite materials which suffer from a large property and geometrical dispersion, either this requires RVE of sizes which cannot usually be obtained numerically, or simply the structural properties exhibit a scatter at the macro-scale. In both cases, the representativity of the micro-scale volume element is lost and Statistical Volume Elements (SVE) [1] should be considered in order to account for the micro-structural uncertainties, which should in turn be propagated to the macro-scale in order to predict the structural properties in a probabilistic way. In this work we propose a non-deterministic multi-scale approach for composite materials following the methodology set in [2]. Uncertainties on the meso-scale properties and their (spatial) correlations are first evaluated through the homogenization of SVEs. This homogenization combines both mean-field method in order to gain efficiency and computational homogenization to evaluate the spatial correlation. A generator of the meso-scale material tensor is then implemented using the spectral method [3]. As a result, a meso-scale random field can be generated, paving the way to the use of stochastic finite elements to study the probabilistic behavior of macro-scale structures. [1] M. Ostoja-Starzewski, X.Wang, Stochastic finite elements as a bridge between random material microstructure and global response, Computer Methods in Applied Mechanics and Engineering, 168, 35–49, 1999. [2] V. Lucas, J.-C. Golinval, S. Paquay, V.-D. Nguyen, L. Noels, L. Wu, A stochastic computational multiscale approach; Application to MEMS resonators. Computer Methods in Applied Mechanics and Engineering, 294, 141–167, 2015. [3] Shinozuka, M., Deodatis, G. Simulation of stochastic processes by spectral representation. Appl. Mech. Rev., 1991: 44(4): 191-204, 1991. [less ▲]

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See detailArchitectural and Environmental Housing Typology Analysis in Huamachuco, Peru
Meliani, Houmam ULg; Teller, Jacques ULg; Attia, Shady ULg

in La Roche, Pablo; Schiler, Marc (Eds.) Passive and Low Energy Architecture Conference (2016, July 12)

This work focuses on the city of Huamachuco, a town 3200 meters above sea level in Northern Peru. The main aim of this study is to share and disseminate technological knowledge on architecture, building ... [more ▼]

This work focuses on the city of Huamachuco, a town 3200 meters above sea level in Northern Peru. The main aim of this study is to share and disseminate technological knowledge on architecture, building technology and lifestyle of Huamachuco inhabitants. The paper objective is to (1) highlight the concept of architectural quality in Huamachuco, (2) compare the living environment of existing traditional dwellings in comparison with newly constructed concrete dwellings, and to (3) identify the reasons for neglecting ecological construction technologies and materials in the new built environment. The research methodology went through different phases that range from qualitative data collection and quantitative measuring, to data analysis and findings reporting. Firstly, a typological study was conducted visiting 110 houses. The typological study enabled us to describe and understand the housing typologies and classify those under four major typologies according to their construction techniques: 1) adobe, 2) rammed earth, 3) concrete and 4) mixed technique. Secondly, detailed field studies were conducted for representative houses representing the four categories. Finally, 10 houses have been thoroughly audited for using measuring equipment to collect data related to temperature, relative humidity, carbon dioxide concentration, lighting intensity, and envelope thermography. [less ▲]

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See detailGestion des flux patients et surpopulation des urgences : Heurs et malheurs de la fonction de « Bed Manager ».
GILLET, Aline ULg; Minder, Anaïs ULg; Nyssen, Anne-Sophie ULg et al

Conference (2016, July 11)

For many years, emergency departments (ED) overcrowding has become a major issue in Public Health. Many studies have demonstrated the efficiency of flow management coordination on this recurrent problem ... [more ▼]

For many years, emergency departments (ED) overcrowding has become a major issue in Public Health. Many studies have demonstrated the efficiency of flow management coordination on this recurrent problem, by offering an interface between the ED, the hospital and out-of-hospital structures and by coordinating patients’ movements towards hospital care units. This was the basis for the implementation of "bed management" coordination program in the ED of the University Hospital of Liège in January 2014. The present study evaluates the adequacy of the Bed Manager (BM) activity with actual ED and hospital workload. Our results describe the rate of intra-hospital patients’ transfers according to the adequacy of the destination unit and time delays for these transfers. Head nurses from specific care units were interrogated about their perceptions of BM activity. We are now convinced by the importance of a participative approach in the development of ED bed management and working procedures, as well as the usefulness of further studies to explore this complex activity. [less ▲]

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See detailComputerized adaptive testing and multistage testing with R
Magis, David ULg; Yan, Duanli; von Davier, Alina

Conference (2016, July 11)

The goal of this workshop is to provide a practical (and brief) overview of the theory on computerized adaptive testing (CAT) and multistage testing (MST), and illustrate the methodologies and ... [more ▼]

The goal of this workshop is to provide a practical (and brief) overview of the theory on computerized adaptive testing (CAT) and multistage testing (MST), and illustrate the methodologies and applications using R open source language and several data examples. The implementations rely on the R packages catR and mstR that have been already or are being developed and include some of the newest research algorithms developed by the authors. This workshop will cover several topics: the basics of R, theoretical overview of CAT and MST, CAT and MST designs, assembly methodologies, catR and mstR packages, simulations and applications. The intended audience for the workshop is undergraduate/graduate students, faculty, researchers, practitioners at testing institutions, and anyone in psychometrics, measurement, education, psychology and other fields who is interested in computerized adaptive and multistage testing, especially in practical implementations of simulation using R. [less ▲]

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See detailAccounting conservatism, analysts’ performance and stock market liquidity
Boussaid, Nabila ULg; Hamza, Taher; Sougné, Danielle ULg

Conference (2016, July 11)

This paper investigates whether conditional accounting conservatism has informational benefits to financial market participants. Using a large sample of French firms over the period 2001-2014, we report ... [more ▼]

This paper investigates whether conditional accounting conservatism has informational benefits to financial market participants. Using a large sample of French firms over the period 2001-2014, we report that accounting conservatism improves the firm information environment by providing verifiable information. We specifically document that increases in accounting conservatism are associated with more accurate analyst earnings forecasts, less dispersed forecasts and less volatility in forecast revisions. We also provide evidence that increases in firm accounting conservatism lead to subsequent increases in stock market liquidity, tested on the price impact dimension. Overall, our findings are in line with conservatism being useful to financial markets participants such as financial analysts and investors. [less ▲]

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See detailMore than just friends? The role of voluntary kin relationships on ageing migrant domestic workers' access to social protection
Vivas Romero, Maria ULg

Conference (2016, July 11)

The feminization of migration led to an academic interest on female migrant domestic worker’s transnational obligations as mothers and family members. Less emphasis has been placed on their own needs in ... [more ▼]

The feminization of migration led to an academic interest on female migrant domestic worker’s transnational obligations as mothers and family members. Less emphasis has been placed on their own needs in terms of care and social protection, particularly in their ageing life period. This contribution makes a case for assessing the role of transnational voluntary kin relationships on ageing-migrant-domestic-worker access to social protection. Transnational voluntary kin relationships are defined as family-type relationships, based not on blood or law association but rather on voluntary agreements. It’s argued that migrants access to transnational voluntary kin relationships depends on their intersectional positioning and replace, overlap or complement traditional family support. These relationships are a social capital that facilitates access to social protection in the areas of labor, social security entitlement, housing and informal practical-symbolic care. Through the analysis emphasis is first placed on how migrants intersectional gender, class, ethnic, generational positioning within the welfare, gender, care, and migration-labor regimes of sending and receiving societies, determines their needs and access to such relationships. Subsequently, the role of two instrumental voluntary kin relationships in migrants access to social protection are explored, meaning: 1- Substitute Voluntary Kin that intervenes when blood or law type family members are dead, underperformed their roles or there are ongoing conflicts, 2- Supplemental Voluntary Kin that intervene when traditional family members that reside in physical or non-physical proximity are unable to perform their roles. Data draws from the life-stories of 8 Peruvian-Colombian ageing migrant domestic workers residing in Brussels and 45 semi-structured interviews with their voluntary and traditional transnational kin residing in various geographical locations. This contribution aims to improve the knowledge on emerging nontraditional family support systems that help to alleviate the reproductive and productive needs of transnational ageing individuals in modern societies. [less ▲]

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See detailA Novel Methodology for Hybrid Fire Testing
Sauca, Ana ULg; Gernay, Thomas ULg; Robert, Fabienne et al

in Proceedings of the 6th European Conference on Structural Control (2016, July 11)

This paper describes a novel methodology for conducting stable hybrid fire testing (HTF). During hybrid fire testing, only a part of the structure is tested in a furnace while the reminded structure is ... [more ▼]

This paper describes a novel methodology for conducting stable hybrid fire testing (HTF). During hybrid fire testing, only a part of the structure is tested in a furnace while the reminded structure is calculated separately, here by means of a predetermined matrix. Equilibrium and compatibility at the interface between the tested “physical substructure” and the “numerical substructure” is maintained throughout the test using a dedicated algorithm. The procedures developed so far are sensitive to the stiffness ratio between the physical and the numerical substructure and therefore they can be applied only in some cases. In fire field, the stiffness of the heated physical substructure may change dramatically and the resulting change in stiffness ratio can lead to instability during the test. To overcome this drawback, a methodology independent of the stiffness ratio has been developed, inspired from the Finite Element Tearing and Interconnecting (FETI) method, which has been originally developed for substructuring in numerical analyses. The novel methodology has been successfully applied to a hybrid fire test in a purely numerical environment, i.e. the physical substructure was also modelled numerically. It is shown that stability does not depend on the stiffness ratio and that equilibrium and compatibility can be consistently maintained at the interface during the fire. Finally, the ongoing experimental program aimed at employing and experimentally validating this methodology is described. [less ▲]

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See detailOptimal returnable transport items management
Limbourg, Sabine ULg; Martin, Adeline; Paquay, Célia ULg

Conference (2016, July 11)

Reducing environmental impact, related regulations and potential for operational benefits are the main reasons why companies share their returnable transport items (RTIs) among the different partners of a ... [more ▼]

Reducing environmental impact, related regulations and potential for operational benefits are the main reasons why companies share their returnable transport items (RTIs) among the different partners of a closed-loop supply chain. Face-to-face interviews with senior executives from seven companies involved in RTIs were conducted to gain a thorough understanding of how they manage the flow of RTIs as well as how they determine the number of RTIs needed in a fleet. Results indicate that RTIs managements are quite diverse, that some common beliefs about RTIs do not apply to all RTI types, and that research efforts are needed in the areas of RTI acquisition; warehouse layout, inventory routing problem; production planning and control; tracking and scheduling. [less ▲]

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See detailHieroglyphic encoding: The Thot Sign-List (TSL) data model and the hieroglyphic signs in Unicode
Polis, Stéphane ULg; Rosmorduc, Serge

Conference (2016, July 11)

In this paper, we review issues related to the existing hieroglyphic sign-lists, focusing especially on the problematic aspects of the 'Manuel de Codage' (1988) and of the so-called 'Hieroglyphica' (2000 ... [more ▼]

In this paper, we review issues related to the existing hieroglyphic sign-lists, focusing especially on the problematic aspects of the 'Manuel de Codage' (1988) and of the so-called 'Hieroglyphica' (2000) for font-designers and users alike. We propose and discuss a data model for the Thot Sign-List (TSL, in prep.). This data model shall lead to the implementation of a structured and systematically referenced hieroglyphic repertoire, which should ultimately allow a sound extension of the Egyptian Hieroglyphs in Unicode. [less ▲]

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See detailCounting time measurement and statistics in gamma spectrometry: the balance
Guembou Shouop, Cébastien Joel ULg; Ndontchueng Moyo, Maurice; Chene, Grégoire ULg et al

Poster (2016, July 11)

Nuclear counting statistics at high count rate are assessed on a γ-ray spectrometer set-up. Our typical gamma spectrometry system consists of a High Purity Germanium (HPGe) detector, liquid nitrogen ... [more ▼]

Nuclear counting statistics at high count rate are assessed on a γ-ray spectrometer set-up. Our typical gamma spectrometry system consists of a High Purity Germanium (HPGe) detector, liquid nitrogen cooling system, preamplifier, detector bias supply, linear amplifier, analog-to-digital converter (ADC), multichannel storage of the spectrum, and data readout devices. Although the system is powerful enough for background measurements, it is important, nowadays, to have a great statistical in short time measurement: which is a challenge for scientists. The purpose of this study was to determine the average time for gamma spectrometry measurement. To detect Uranium, Thorium and their respective daughters and Potassium series with a relative related error less than 1%, it was found that it is necessary to count during a minimum of 24 Hours (86,400 s). This result is in accordance to the literature with planar geometry detector. These results conduct us to make the following three guidelines for selecting the detector best suited for an application: 1. The more detector material available (germanium semi-conductor), the higher the full-energy peak efficiency. 2. The smaller the distance between the detector and the source material, the higher the full- energy peak efficiency. 3. While better resolution gives a better MDA, the resolution contributes only as the square root to the MDA value, whereas the MDA is proportional to the full-energy peak efficiency. This idea came to us by comparing the spectra of measuring radioactivity lasts for 12 hours in the day that does not fully covered the night spectra for the same sample. The conclusion after several investigations became clearer: to remove all effects of radiation from outside (earth, sun and universe) our system, it is necessary to measure the background for 24, 48 or 72 hours. In the same way, the samples have to be measures for 24, 48 or 72 hours to be safe to be purified the measurement (equality of day and night measurement). It is also possible to not use the background of the winter in summer. Depend to the energy of radionuclide we seek, it is clear that the most important steps of a gamma spectrometry measurement are the preparation of the sample and the calibration of the detector. [less ▲]

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See detailReproducibility of a tennis serve protocol
Tubez, François ULg; FORTHOMME, Bénédicte ULg; Croisier, Jean-Louis ULg et al

Conference (2016, July 08)

INTRODUCTION Serve in modern tennis game is a real offensive weapon for players. In kinematic analysis, it is the most studied stroke of this game because it is the only stroke played in a closed skill ... [more ▼]

INTRODUCTION Serve in modern tennis game is a real offensive weapon for players. In kinematic analysis, it is the most studied stroke of this game because it is the only stroke played in a closed skill. Players have a maximum of control on this stroke. It is unclear whether 3D kinematic tests are reproducible for the same player under identical conditions and if a familiarization session is necessary. In practice, with professional players, who have little time available to perform tests, familiarization sessions are difficult. The aim of our study is to measure the reproducibility of a 3D serve protocol test. METHODS Nine tennis players (righties, regional level, 20 ± 2 years) were asked to hit first flat serves in a 1 m² area placed on the "T" zone of deuce diagonal of the tennis court. Two identical tests are performed one week apart. For each test, we selected the three best serves of the 25 trials (with the highest speed and the highest accuracy). Kinetics measurements were performed using a 3D analysis system (Codamotion), a force platform (Kistler) and a radar gun. 28 markers were placed on the players’ bodies to measure kinematics of the movements: ankles, knees, hips, trunk, shoulder, elbow and wrist dominant side. We measured ball speed, leg drive, linear velocity of the racket and joints, joints range of motion and maximum angular velocities at different positions (armed, maximum external rotation and impact) (1). RESULTS All analyzed parameters (linear speeds of racket and joints, leg drive force, joint angles and angular velocities) are reproducible with exception of a small part of them. Our study shows that 5,7% (7 of 122 measurements) joint position parameters and 8,3% (4 of 48 measures) angular velocity parameters are not reproducible from a session to another. DISCUSSION Various errors sources encountered in 3D analysis can justify the presence of non-reproducible parameters (2-3). However, after this work, we can state that the established protocol provides reproducible results when analyzing the tennis serve. [less ▲]

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See detailMultiscale study of the Carolingian mosaic of Germigny-des-Prés (Loiret, Fr
Van Wersch, Line ULg; Kronz, L.; Simon, K. et al

Conference (2016, July 08)

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See detailValorization of CO2 for the preparation of advanced materials
Gennen, Sandro ULg; Grignard, Bruno ULg; Thomassin, Jean-Michel ULg et al

Conference (2016, July 07)

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See detailAu-delà des success stories, quel processus de libération ? Étude de cas au sein du secteur public belge
Fox, Fanny ULg; Pichault, François ULg

Conference (2016, July 07)

Si l’on peut s’attendre à ce qu’un processus de libération s’inscrive logiquement dans une perspective polyphonique (Pichault, 2013) – marquée par l’importance de la communication et de la mobilisation ... [more ▼]

Si l’on peut s’attendre à ce qu’un processus de libération s’inscrive logiquement dans une perspective polyphonique (Pichault, 2013) – marquée par l’importance de la communication et de la mobilisation des acteurs, mais aussi par les affrontements entre voix opposées (Sullivan & McCarthy, 2008), il peut tout aussi bien être sous-tendu par un volonté de contrôle et de disciplinarisation du corps social relevant davantage du panoptisme. À travers une recherche qualitative, nous explorons la mise en œuvre du processus de libération : ses étapes, les obstacles rencontrés et la façon dont ils ont été – ou non – surmontés, l’implication des différentes parties prenantes et les négociations y afférentes, les résistances et les tensions suscitées, etc. Cet article, de nature empirique, repose sur une étude de cas originale réalisée dans le secteur public belge, marquée par une forte présence syndicale. Il ambitionne d’éclairer certaines contradictions de l’entreprise libérée envisagée sous l’angle de la gestion du changement. [less ▲]

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See detailRestricted interests in autism with versus without speech onset delay : the importance of perceptually versus thematically organized interests
Chiodo, Liliane ULg; Majerus, Steve ULg; Eusèbe, Sandrine et al

Poster (2016, July 07)

Objectives : To explore whether autistic adults with vs without speech delay also differ in the perceptual vs thematic nature of their restricted interests.

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See detailNonlinear analysis of compliant mechanisms: application to tape springs
Dewalque, Florence ULg; Bruls, Olivier ULg

Poster (2016, July 07)

Brief summary of the mechanical behaviour of tape springs. Main results obtained by the means of finite element models. Description of the experimental set-up and results. See the extended abstract for ... [more ▼]

Brief summary of the mechanical behaviour of tape springs. Main results obtained by the means of finite element models. Description of the experimental set-up and results. See the extended abstract for more details. [less ▲]

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See detailL’argumentation de l’image scientifique : une affaire de méréologie
Dondero, Maria Giulia ULg

in Pollet, Marie-Christine; Glorieux, Carole (Eds.) Argumenter dans les écrits scientifiques (2016, July 07)

Ce texte vise à étudier, dans une perspective sémiotique, le discours scientifique de recherche et celui de la vulgarisation et notamment les images présentes dans ces deux genres de discours. Nous ... [more ▼]

Ce texte vise à étudier, dans une perspective sémiotique, le discours scientifique de recherche et celui de la vulgarisation et notamment les images présentes dans ces deux genres de discours. Nous examinons des travaux relevant de l’astrophysique et notamment la manière dont les images argumentent. Le corpus sera abordé à partir de la notion de rhétorique entendue comme un ensemble d’opérations méréologiques. Nous reprendrons à ce propos la théorie de l’iconicité de Jean-François Bordron, illustrée par ses deux derniers livres, L’iconicité et ses images (2011) ainsi qu’Image et vérité. Essais sur la dimension iconique de la connaissance (2013). [less ▲]

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See detailNovel butanol pretreatment significantly improves delignification and saccharification of different lignocellulosic biomasses
Schmetz, Quentin ULg; Teramura, Hiroshi; Jacquet, Nicolas ULg et al

Poster (2016, July 07)

Organosolv pretreatment using diluted acid and butanol allows the separation of cellulose, hemicelluloses and lignin into three distinct phases. The butanol process has been investigated on six different ... [more ▼]

Organosolv pretreatment using diluted acid and butanol allows the separation of cellulose, hemicelluloses and lignin into three distinct phases. The butanol process has been investigated on six different biomasses: tall fescue, sugarbeet pulp, sugarcane bagasse, beech wood, eucalyptus and Japanese cedar. Dilute acid pretreatment has been performed under similar conditions for comparison. [less ▲]

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See detailDiversity and evolution of transposable elements in the Arabidopsis lyrata and A. halleri genomes
Caron, Thibault; Legrand, Sylvain; Schvartzman Echenique, Maria Sol ULg et al

Conference (2016, July 07)

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See detailIntegrated microfluidic device for in line SERS detection for glyphosate and related metabolites
Emonds-Alt, Gauthier ULg; Malherbe, Cédric ULg; Monbaliu, Jean-Christophe ULg et al

Poster (2016, July 07)

The goal of this work is to develop a quantitative analytical method for the glyphosate and its major metabolite the aminomethylphosphonic acid (AMPA) by coupling microfluidics with surface enhanced Raman ... [more ▼]

The goal of this work is to develop a quantitative analytical method for the glyphosate and its major metabolite the aminomethylphosphonic acid (AMPA) by coupling microfluidics with surface enhanced Raman spectroscopy (SERS). This work is divided into 4 axes : (a) bimetallic nanoparticles synthesis in a microreactor, (b) nanoparticles functionnalisation, (c) SERS quantification of glyphosate/AMPA and (d) miniature prototype development composed of axes a to c. The first section aims at the synthesis of bimetallic nanoparticles (Au-Ag, Au-Cu and Ag-Cu) in a microfluidic device. This microfluidic device integrates a first section for the synthesis of monometallic nanoparticles (core) and a second section for the reductive deposition of a second metal (shell). The second axe of this work deals with the functionnalisation of nanoparticles to improve the selectivity of this method for the selected analytes. Two types of functionnalisation are studied : PEGylation (a) with multi-arm PEG ending with -SH and/or (b) with linear heterobifunctionnal PEG. The third axe consists in measuring quantitatively glyphosate and AMPA in different matrices, such as water, urine and fruit juice. Finally, the forth axe deals with the development of a portable detection system to perform on-site analysis. This prototype integrates the microfluidic device for nanoparticles synthesis, their functionnalisation, an injection port followed by a mixing section for the sample and an integrated Raman spectrometer for in-line analysis. [less ▲]

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See detailDevelopment and optimization of a TD-GC/MS methodology for detection and quantifi cation of furan released in air using of an experimental design.
Alsafra, Zouheir ULg; Scholl, Georges ULg; Romain et al

Poster (2016, July 07)

In the aim of understanding the way in which human is exposed to furan present in the air of an occupational area, an analytical method of Thermal desorption-gas chromatography/Mass spectrometry (TD-GC/MS ... [more ▼]

In the aim of understanding the way in which human is exposed to furan present in the air of an occupational area, an analytical method of Thermal desorption-gas chromatography/Mass spectrometry (TD-GC/MS) has been developed and optimized using a Plackett–Burman experimental design. This method was then used to study the phenomena of diffusion of furan released in air from a contamination source. This source of furan is simply a coffee machine located in a closed controlled room. Results show that furan concentration increases quickly over time after turning on the coffee machine until reaching a maxima. Then it starts to decrease slowly. On the other hand, concentration of furan seems to be identical everywhere in the conditioned room in each moment. [less ▲]

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See detailSingle Molecule force spectroscopy on helical foldamers
Devaux, Floriane ULg; Li, Xuesong; Huc, Ivan et al

Conference (2016, July 07)

Detailed reference viewed: 5 (4 ULg)
See detailNeighborhood search approaches for multi-trip vehicle routing problems
François, Véronique ULg; Arda, Yasemin ULg; Crama, Yves ULg

Conference (2016, July 06)

We introduce two large neighborhood search approaches for solving the multi-trip vehicle routing problem (MTVRP), where each vehicle can perform several routes to serve a set of customers. The problem ... [more ▼]

We introduce two large neighborhood search approaches for solving the multi-trip vehicle routing problem (MTVRP), where each vehicle can perform several routes to serve a set of customers. The problem specifically arises when travel times between customers are short and/or when demands are large. It has been commonly solved in the literature by mixing vehicle routing heuristics and bin packing techniques aimed at assigning routes to vehicles. As an alternative, we propose specific operators that tackle the routing and the assignment aspects of the problem simultaneously. The introduced methods are compared both for the MTVRP and the version with time windows, in which the assignment part of the problem becomes more challenging. In the latter, besides considering a time window at the depot, the working time of each vehicle may not exceed a maximum duration, while its start time is a decision variable. Beyond providing several best known solutions for benchmark instances of the MTVRP, we focus on understanding the behavior of the algorithms. An automatic configuration tool is used, not only to improve the quality of the results, but also as a mean to gain knowledge about algorithm design options and their interactions. We question the impact of several heuristic components and in particular those of the roulette wheel mechanism and of the adaptive memory of routes. [less ▲]

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See detailLe stéthoscope au bout du clavier : la médecine générale belge à l'ère de l'e-Santé
Slomian, Cynthia ULg

Conference (2016, July 06)

Cette communication se propose d’explorer l’informatisation de la médecine générale en Belgique. Nous parcourrons la sociologie de la santé dans la littérature, en revenant sur les approches s’intéressant ... [more ▼]

Cette communication se propose d’explorer l’informatisation de la médecine générale en Belgique. Nous parcourrons la sociologie de la santé dans la littérature, en revenant sur les approches s’intéressant aux rôles respectifs du médecin et du malade (Parsons, 1951), à la division du travail médical (Freidson, 1984) et également à la segmentation de la profession médicale (Bucher et Strauss, 1961). Nous intégrerons ensuite un nouvel élément au raisonnement sociologique afin de compléter et dépasser les approches traditionnelles : la digitalisation de la pratique médicale. En effet, il paraît indispensable de comprendre les implications, d’une part, de l’utilisation de plus en plus fréquente des TIC par les médecins et, d’autre part, du partage de données de santé, qui est au cœur de nombre de politiques publiques en Europe et ailleurs à l’heure actuelle. Plus précisément, nous reviendrons sur les changements récents dans le paysage belge des soins de santé, qui intègre l’e-Santé au cœur des politiques publiques depuis 2013. L’étude de documents ainsi que du discours des acteurs institutionnels constituera les fondements de l’analyse exploratoire proposée. Nous espérons ainsi montrer pourquoi la sociologie de la médecine doit intégrer le numérique comme élément essentiel de compréhension pour étudier les relations entre professionnels de la santé, mais également pour considérer le colloque singulier médecin-patient sous un jour nouveau. [less ▲]

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See detailCity dwellers without a background
Meulemans, Germain ULg

Conference (2016, July 06)

One implication of the notion of taskscape is to make an argument against the idea of the landscape being a 'background for life'. It entails that in a truly ecological view of the world, there cannot be ... [more ▼]

One implication of the notion of taskscape is to make an argument against the idea of the landscape being a 'background for life'. It entails that in a truly ecological view of the world, there cannot be such a thing as a 'background'. This paper examines how these entailments may concern present discussions about 'nature in town' - a notion that has gained importance in different fields since the 1990s. From offshoots in population ecology or ethology to the development of state led initiatives aiming at managing species and ecosystems in towns, it has added city areas to the list of biodiversity hot spots. Anthropologists are not left out of the subject, and have generally invested the notion as a 'hybrid' in which common categories of nature and culture are blurred and re-defined. The paper argues that in these approaches cities are often taken as a background to life, in terms similar to those Ingold aimed at overpassing in his writings on landscape. Building on the case of the study of city soils, I suggest that an approach in which soils are a multispecies compound taken in pedogenesis may provide a way around the 'nature in town' approach. Prolonging the recent soil science assumption that soil organisms 'altogether are the soil', I argue that humans too join them in pedogenesis. In this, the city stops being a background for lives, and becomes a processual entity in which humans, species and materials in fluxes shape one another. [less ▲]

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See detailEtude de la composition chimique de Pseudotsuga menziesii (Mirb.) Franco et évaluation de l’impact de divers prétraitements lignocellulosiques sur l’extraction de la lignine
Berchem, Thomas ULg; Schmetz, Quentin ULg; Jacquet, Nicolas ULg et al

Poster (2016, July 06)

La raréfaction des ressources fossiles est une certitude à l’heure actuelle. Il est donc primordial de trouver des voies de production plus durables pour des produits de consommation courante. Le ... [more ▼]

La raréfaction des ressources fossiles est une certitude à l’heure actuelle. Il est donc primordial de trouver des voies de production plus durables pour des produits de consommation courante. Le bioraffinage fait partie des solutions envisagées pour substituer les matériaux originaires de la filière pétrochimique. Dans cette optique, ce travail se focalise sur l’extraction et la caractérisation de la lignine à partir d’une biomasse présente en abondance en région Wallonne, Pseudotsuga menziesii (Mirb.) Franco (Douglas). Ce travail vise à montrer l’impact de divers prétraitements lignocellulosiques, tant en terme de rendements et de pureté d’extraction qu’au niveau de la modification de la structure et des propriétés des lignines. Ces différents paramètres sont évalués par des techniques gravimétriques (Klason), chromatographiques (chromatographie d’exclusion stérique) et spectroscopiques (RMN 2D HSQC). Pseudotsuga menziesii (Mirb.) Franco a été préalablement caractérisé par son taux de matière lignocellulosique (cellulose, hémicelluloses, lignine), ainsi que sa teneurs en cendres, en protéines et en extractibles (à l’eau et à l’éthanol). Les lignines natives ont été caractérisées par RMN 2D HSQC. [less ▲]

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See detailGamifier un quiz – Effet graduel sur la performance, l’immersion et la perception de compétence
le Maire, Nathalie ULg; Fauconnier, Marie-Laure ULg; Colaux, Catherine ULg et al

Conference (2016, July 06)

Dans un contexte marqué par l’arrivée d’une génération pour laquelle les technologies, les réseaux sociaux et les jeux en ligne relèvent de l’évidence (Stein, 2013; Weiler, 2004), le jeu a souvent été ... [more ▼]

Dans un contexte marqué par l’arrivée d’une génération pour laquelle les technologies, les réseaux sociaux et les jeux en ligne relèvent de l’évidence (Stein, 2013; Weiler, 2004), le jeu a souvent été qualifié de véhicule d’une pédagogie rendant l’étudiant acteur de son apprentissage, conférant une dimension de défi aux activités éducatives et générant une motivation intrinsèque (Foster, 2008; Kang & Tan, 2008; McFarlane et al., 2002; Mitchell & Savill-Smith, 2004; Papastergiou, 2009). Ce potentiel éducatif du jeu a cependant été souvent associé à des jeux immersifs (de Freitas, 2006) requérant la mise en œuvre d’une trame narrative et dont le développement peut s’avérer couteux. L’utilisation de mini-jeux est considérée comme une solution alternative à ces « serious games » complexes car ils permettent d’enseigner un grand nombre de concepts tout en générant de faibles coûts de développement (Illanas, Gallego, Satorre, & Llorens, 2008). Ceux-ci présentent des règles basiques, sont faciles à jouer et conçus comme objets d’apprentissage de sorte qu’il soit aisé pour l’étudiant de percevoir les informations essentielles et que leur pratique soit bénéfique pour l’apprentissage (Frazer, Argles, & Wills, 2007). La gamification, à savoir la transposition des principes issus de l’univers du jeu au domaine de l’éducation (Deterding, Dixon, Khaled, & Nacke, 2011), ne porte donc pas ici sur des jeux de simulation immersifs mais vise plus réalistement la transposition à des activités d’apprentissage d’un certain nombre de principes et de leviers à l’œuvre dans des mini-jeux populaires tel que Candy Crush. La question de recherche qui a guidé l’expérience décrite ci-après concerne l’évaluation du potentiel pédagogique de l’utilisation d’un mini-jeu de ce type dans un cours de chimie générale en complément des supports pédagogiques plus classiquement utilisés en première année d’université. Concrètement, ce mini-jeu appelé « Atomica » se présente comme un quiz d’entrainement portant sur un chapitre réputé difficile du cours, l’atomistique. Ce quiz a fait l’objet de quatre versions activant chacune un nombre croissant d’éléments de gamification (indiqués en gras) décrits par plusieurs auteurs comme étant les « ingrédients » ou « building blocks » d’un bon jeu (Bunchball Inc., 2010; Dignan, 2011; Reeves & Read, 2013) : - La version contrôle du QCM se présente comme similaire aux évaluations formatives couramment utilisées à l’université ; - La version 1 segmente le QCM en six niveaux de difficulté ; - La version 2 ajoute un feedback automatisé aux niveaux de difficulté ; - La version 3 présente une version maximaliste de la gamification puisque, aux éléments précédents, elle ajoute un compte à rebours, des indices dont l’appel engendre une perte de points, un classement des meilleurs joueurs et un indicateur social (possibilité de se situer par rapport à la communauté de joueurs). Ce choix d’un dispositif graduel se justifie notamment par l’intérêt pour la détection d’un seuil à partir duquel l’ajout d’éléments de gamification fait basculer la perception d’un quiz habituel vers un artefact relevant du mini-jeu et générant ainsi un état de flow chez le joueur. Chaque version a été soumise à un groupe d’une trentaine d’étudiants, selon une procédure expérimentale contrôlée, avec pour objectif la collecte de données (en cours) sur : - L’état de flow ou expérience optimale engendré par chacune des versions (orientation comparative) défini comme un état subjectif de bien-être (Csikszentmihalyi, 1990) engendrant une immersion totale dans l’activité. Afin de mesurer le flow, une échelle spécifique aux jeux éducatifs (EGameFlow) développée en 2009 (Fu, Su, & Yu, 2009) a été utilisée dans le cadre de cette étude. - Une des trois composantes du modèle de la dynamique motivationnelle de Viau, la perception du sentiment de compétence (Bandura, 1993; Pajares, 2014) considéré comme un moteur essentiel à l’apprentissage et un déterminant de l’intérêt pour une discipline scolaire. - La performance à un test de connaissance soumis aux étudiants avant et après l’expérience de jeu. Les motivations sous-tendant le processus d’exploration des mini-jeux sont à chercher du côté d’un certain discours pédagogique qui prône l’inscription d’une dimension ludique dans les apprentissages en enseignement supérieur. Nourrie par ses résultats expérimentaux, la communication proposera un retour réflexif plus général sur la valeur, les limitations et les conditions de réalisation de ce discours. [less ▲]

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See detailDe ferrovipathe à vaporiste. Ethnographie de la restauration de locomotives à vapeur
Lejeune, Christophe ULg

Conference (2016, July 06)

Voilà un demi-siècle, quand les sociétés nationales de chemin de fer ont délaissé les locomotives à vapeur, des amateurs ont décidé de sauvegarder ce patrimoine ferroviaire. Depuis, leurs associations ... [more ▼]

Voilà un demi-siècle, quand les sociétés nationales de chemin de fer ont délaissé les locomotives à vapeur, des amateurs ont décidé de sauvegarder ce patrimoine ferroviaire. Depuis, leurs associations recrutent chaque jour des volontaires, issus d'horizons variés. Le débutant commence par trier des boulons, poncer un châssis ou appliquer un enduit contre la corrosion. Un tuteur lui apprend ensuite comment allumer et alimenter un foyer à charbon. En dépit de ce compagnonnage, le quotidien des volontaires ne correspond pas totalement à celui des artisans (Sennett, 2010). S'ils s'identifient volontiers aux cheminots, ils critiquent les sociétés nationales qui délaissent leur patrimoine. Comme le métro (Thibault, 2013) ou les automobiles (Dant, 2010), les locomotives se restaurent en coulisse. Leurs réparateurs ne bénéficient donc pas de la reconnaissance du public. Ils n'entendent pas moins opérer avec «professionnalisme» : ils maintiennent en activité d'antiques machines tout en respectant les (exigeantes) règles de sécurité actuelles. Et ils y arrivent sans disposer de pièces de rechange. Ainsi, malgré son ressort nostalgique, la préservation ferroviaire préfigure les collectifs actuels de réparateurs («repair café»). Loisir, sacerdoce, travail-à-côté, artisanat, tremplin pour l'emploi ? La configuration protéiforme de la restauration de locomotives à vapeur interroge la pertinence des catégories sociologiques susceptibles d'en rendre compte. [less ▲]

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See detailOptimisation de la production d’acide furan-2,5-dicarboxylique à partir de déchets verts pour la conception de plastiques bio-basés
Istasse, Thibaut ULg; Jacquet, Nicolas ULg; Richel, Aurore ULg

Poster (2016, July 06)

Afin de trouver des alternatives renouvelables aux produits issus de l’industrie pétrochimique, de nombreuses voies de recherches ont été explorées. Une voie prometteuse est la technologie des dérivés ... [more ▼]

Afin de trouver des alternatives renouvelables aux produits issus de l’industrie pétrochimique, de nombreuses voies de recherches ont été explorées. Une voie prometteuse est la technologie des dérivés furaniques. Parmi ces composés, le 5-hydroxyméthylfurfural (5-HMF) fait partie des molécules plateformes les plus importantes1. Il s’agit d’un produit de dégradation obtenu par déshydratation des hexoses2,3. Le 5-HMF peut servir de base à la conception de nombreuses molécules valorisables comme l’acide furan-2,5-dicarboxylique dont la structure proche de l’acide téréphtalique permet des applications dans la conception de polymères bio-basés3. L’acide furan-2,5-dicarboxylique respecte la législation REACH selon l’European Chemicals Agency4. Un rapport de l’EFSA de 2014 a démontré que cette substance ne posait pas de problème de toxicité lors de son utilisation comme monomère de base dans les plastiques d’emballage pour aliments5. Selon la société Avantium, le FDCA peut être utilisé pour produire un plastique entièrement bio-basé, le polyéthylène furanoate (PEF), qui affiche des performances supérieures à celle du poléthylène téréphtalate (PET) en termes de stabilité thermique, de propriétés mécaniques et de perméabilité aux gaz6. Si le FDCA peut être convertit en de nombreux produits à haute valeur ajoutée, il existe toutefois un frein majeur à son exploitation industrielle : son précurseur, le 5-HMF, n’est pas encore produit en grande quantité1. Ce problème est dû principalement à la déshydratation non sélective des sucres de la biomasse qui aboutit à de nombreux autres produits que le 5-HMF. La première difficulté à surmonter est donc la mise au point d’un procédé permettant de déshydrater de manière efficace et sélective les sucres de la biomasse. Le 5-HMF est également peu stable en milieu acide où il se décompose en acide formique et en acide lévulinique2. L'enjeu du projet de recherche présenté est donc l’optimisation de la production de 5-HMF à partir d’un ou plusieurs types de biomasses dans un premier temps, puis l’optimisation de la conversion du 5-HMF produit en FDCA. Les paramètres à prendre en compte sont notamment les sources de biomasse, l’efficacité des prétraitements concernant l’extraction des sucres, la sélectivité et l’efficacité de la conversion de ces sucres en 5-HMF (système mono- ou biphasique), l’étude de divers catalyseurs, le coût des traitements, etc… [less ▲]

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See detailDébattre la mesure : l'imagination sociologique de Steve reich
Orianne, Jean-François ULg

Conference (2016, July 06)

Cette communication vise à identifier les apports de la musique de Steve Reich à la sociologie. Sa musique présente trois caractéristiques majeures : elle se compose à partir d’un matériau empirique ... [more ▼]

Cette communication vise à identifier les apports de la musique de Steve Reich à la sociologie. Sa musique présente trois caractéristiques majeures : elle se compose à partir d’un matériau empirique recueilli sur le terrain ; elle est un acte politique et culturel ; elle est une théorie des processus. La musique de Steve Reich affecte la sociologie sur ces trois points : elle interpelle le sociologue sur son métier et son engagement dans le monde social, l’interroge sur ses pratiques et ses méthodes, elle éclaire même ses propres concepts (en particulier celui de processus). L’auteur propose d’extraire du travail de composition de Steve Reich quelques éléments utiles pour le métier de sociologue : 1) une contribution à la théorie des processus sociaux ; 2) la question du rapport à l’empirie ; 3) le problème de l’engagement (politique, moral et culturel). [less ▲]

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See detailInsight on Van Dongen’s La Violoiste by hyperspectral imaging and MA-XRF
Herens, Elodie ULg; Strivay, David ULg; Walter, Philippe et al

Conference (2016, July 06)

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See detailLa production en masse de microalgues: limitations actuelles, perspectives d'amélioration et applications dans le domanaine des pigments valorisables
Franck, Fabrice ULg

Conference (2016, July 06)

Actuellement les productions industrielles de microalgues sont exploitées pour diverses applications commerciales. Les cultures sont le plus souvent réalisées sur le mode photoautotrophe, c’est-à-dire ... [more ▼]

Actuellement les productions industrielles de microalgues sont exploitées pour diverses applications commerciales. Les cultures sont le plus souvent réalisées sur le mode photoautotrophe, c’est-à-dire basées sur l’absorption de lumière pour l’incorporation du carbone du CO2 dans la biomasse. Bien que les productivités atteignent des valeurs respectables par rapport aux rendements agricoles, elles restent limitées par de faibles rendements de conversion de l’énergie solaire, en comparaison avec le rendement théorique maximum. Les raisons généralement évoquées pour expliquer cette limitation sont principalement l’atténuation de la lumière dans les cultures et la saturation de la photosynthèse en surface. Les pistes d’amélioration proposées concernent d’une part la géométrie des systèmes de culture et, d’autre part, l’amélioration génétique des souches de microalgues en vue d’une meilleure efficience énergétique. Des cultures hétérotrophes en fermenteur sont également en développement. Avec les limitations actuelles de productivité, les coûts de production restent élevés pour des applications à faible valeur ajoutée. Les pigments des microalgues, par leur variété et leurs multiples débouchés, représentent une catégorie en expansion de produits économiquement viables. Ils comprennent principalement les caroténoïdes de microalgues vertes et de diatomées, ainsi que les phycobilines des cyanobactéries. [less ▲]

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See detailDu tableau au plan. Remake et transmédialité dans "Shirley" (2013) de Gustav Deutsch
Belloi, Livio ULg

Conference (2016, July 06)

Cette communication prend pour objet "Shirley" (2013), le dernier en date des films de Gustav Deutsch. Dans ce film de fiction, l'artiste autrichien vise à recréer, à incarner et à animer treize tableaux ... [more ▼]

Cette communication prend pour objet "Shirley" (2013), le dernier en date des films de Gustav Deutsch. Dans ce film de fiction, l'artiste autrichien vise à recréer, à incarner et à animer treize tableaux du grand peintre américain Edward Hopper. Partant de ce constat, il s'agit d'étudier au plus près les enjeux théoriques et esthétiques dont ce remake transmédial est porteur. [less ▲]

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See detailQuelles conditions favorisent le changement de pratiques lors de la mise en oeuvre d'un dispositif didactique?
Dellisse; De Croix, Séverine ULg; Dumay, Xavier et al

Conference (2016, July 05)

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See detailMoresnet-Neutre face au processus de l'Etat-Nation La transformation d'un territoire contesté en pays
Robelin, Cyril ULg

Conference (2016, July 05)

In dieser Präsentation werden die verschiedenen Umwandlungen des besonderen Gebiets von Neutral-Moresnet untersucht. In der Nähe von Aachen war es zwischen dem Wiener Vertrag von 1815 und dem Versailler ... [more ▼]

In dieser Präsentation werden die verschiedenen Umwandlungen des besonderen Gebiets von Neutral-Moresnet untersucht. In der Nähe von Aachen war es zwischen dem Wiener Vertrag von 1815 und dem Versailler Vertrag von 1919 unter der gemeinsamen Federführung von den Niederländen (Belgien ab 1831-1839) und von Preußen (Deutschland ab 1870). Inwiefern hat der Prozess des Nationalstaates das damalig umstrittene Dorf Moresnet in einen angeblich unabhängigen Staat umgewandelt? Wichtig ist die Frage der Umstrukturierung von früheren politischen und geistigen Systemen in neue Organisationen. Am Ende des neunzehnten Jahrhunderts scheinen die Stöße des Nationalismus und des Nationalstaates dieses Paradigma in ganz Westeuropa durchzusetzen: ein Staat für eine Nation. Dieses interessante Paradigma gibt es auch in Moresnet, indem das Gebiet alle Insignien hat (Fahne, Währung, Briefmarken, Hymnen), wie bei ihren Nachbarstaaten. Von der Presse dieser Epoche wird das Dorf als der kleinste Staat der Welt bezeichnet. Dieser Nationalstaat wirft neue Fragen auf, wie zum Beispiel die Frage der Staatsangehörigkeit oder die des Rechtsvakuums. Dennoch erregen diese strukturellen Umwandlungen einige Widerstandsbewegungen gegen die Entwicklung des Nationalstaats, die dann Innovationen erfordern. Moresnet wird als "Anti-Nationalstaat" angesehen, mit dem Willen, diesen Prozess dank dem Esperanto-Utopie zu überwinden. Außenbeobachter bezeichnen es als imaginierter, sogar imaginärer Ort (mit Vampiren…). Diese Einflüsse tragen zu Innovationen bei, indem sie die bereits bestehenden Strukturen neu erfinden. Das Thema wird aus unveröffentlichten Archiven, aus Presseausschnitten und aus Schul- und Wissenschaftsbüchern behandelt. Umwandlungen und Umstrukturierungen der politischen und geistigen Systeme sind durch die Entwicklung des Nationalstaats und des Nationalismus in Westeuropa entstanden. Der Fall von Moresnet ist ein typisches Beispiel, das ermöglicht, diese Umwandlungen und diese Umstrukturierungen der politischen und geistigen Systeme besser zu verstehen. Tatsächlich erträgt, begleitet und belebt Moresnet diese gleiche Dynamik des Wandels durch seine Innovationen und seinen spezifischen diplomatischen Status. [less ▲]

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